cc.tooyoung.common.db.JdbcTemplate.java Source code

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package cc.tooyoung.common.db;

/*
 * Copyright 2002-2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.ConcurrentHashMap;

import javax.sql.DataSource;

import org.springframework.core.CollectionFactory;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.InvalidDataAccessApiUsageException;
import org.springframework.dao.support.DataAccessUtils;
import org.springframework.jdbc.CannotGetJdbcConnectionException;
import org.springframework.jdbc.SQLWarningException;
import org.springframework.jdbc.core.BatchPreparedStatementSetter;
import org.springframework.jdbc.core.CallableStatementCallback;
import org.springframework.jdbc.core.CallableStatementCreator;
import org.springframework.jdbc.core.ColumnMapRowMapper;
import org.springframework.jdbc.core.ConnectionCallback;
import org.springframework.jdbc.core.InterruptibleBatchPreparedStatementSetter;
import org.springframework.jdbc.core.ParameterDisposer;
import org.springframework.jdbc.core.PreparedStatementCallback;
import org.springframework.jdbc.core.PreparedStatementCreator;
import org.springframework.jdbc.core.PreparedStatementSetter;
import org.springframework.jdbc.core.ResultSetExtractor;
import org.springframework.jdbc.core.ResultSetSupportingSqlParameter;
import org.springframework.jdbc.core.RowCallbackHandler;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.RowMapperResultSetExtractor;
import org.springframework.jdbc.core.SingleColumnRowMapper;
import org.springframework.jdbc.core.SqlOutParameter;
import org.springframework.jdbc.core.SqlParameter;
import org.springframework.jdbc.core.SqlProvider;
import org.springframework.jdbc.core.SqlReturnResultSet;
import org.springframework.jdbc.core.SqlRowSetResultSetExtractor;
import org.springframework.jdbc.core.StatementCallback;
import org.springframework.jdbc.datasource.ConnectionProxy;
import org.springframework.jdbc.datasource.DataSourceUtils;
import org.springframework.jdbc.support.JdbcUtils;
import org.springframework.jdbc.support.KeyHolder;
import org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator;
import org.springframework.jdbc.support.SQLExceptionTranslator;
import org.springframework.jdbc.support.SQLStateSQLExceptionTranslator;
import org.springframework.jdbc.support.nativejdbc.NativeJdbcExtractor;
import org.springframework.jdbc.support.rowset.SqlRowSet;
import org.springframework.util.Assert;

import cc.tooyoung.common.util.ApiLogger;
import cc.tooyoung.common.util.TimeStatUtil;

/**
 * <b> To get jdbcTemplate from m-s dbs </b>
 * 
 * <p>We can freely update the get strategy, for we can change read/write datasource if the datasource is crash or cannot connect,
 * we can retry get connection if some connection is stale
 * </p>
 * 
 * @author fishermen
 *
 */
public class JdbcTemplate extends JdbcAccessor {

    private DataSource dataSource;
    private List<DataSource> dataSourceSlaves = new ArrayList<DataSource>();
    private int readTryGetConCount = 10;
    private int writeTryGetConCount = 10;
    private int resource;

    private Map<DataSource, SQLExceptionTranslator> exceptionTranslators = new ConcurrentHashMap<DataSource, SQLExceptionTranslator>();

    private Random random = new Random();

    public DataSource getDataSource() {
        return dataSource;
    }

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;

        try {
            String port = ((com.mchange.v2.c3p0.ComboPooledDataSource) dataSource).getJdbcUrl().split(":")[3]
                    .split("/")[0];
            resource = TimeStatUtil.DB_TYPE + Integer.parseInt(port);
            TimeStatUtil.register(resource);
        } catch (Exception e) {
            //port null
        }
    }

    public void setDataSourceSlaves(List<DataSource> dataSourceSlaves) {
        this.dataSourceSlaves = dataSourceSlaves;

        try {
            String port = ((com.mchange.v2.c3p0.ComboPooledDataSource) dataSourceSlaves.get(0)).getJdbcUrl()
                    .split(":")[3].split("/")[0];
            resource = TimeStatUtil.DB_TYPE + Integer.parseInt(port);
            TimeStatUtil.register(resource);
        } catch (Exception e) {
            //port null
        }
    }

    public int getReadTryGetConCount() {
        return this.readTryGetConCount;
    }

    public void setReadTryGetConCount(int readTryGetConCount) {
        this.readTryGetConCount = readTryGetConCount;
    }

    public int getWriteTryGetConCount() {
        return this.readTryGetConCount;
    }

    public void setWriteTryGetConCount(int writeTryGetConCount) {
        this.writeTryGetConCount = writeTryGetConCount;
    }

    /**
     * model: master: write & read; slave: read
     * @param isWrite
     * @return
     */
    public DataSource getDataSource(boolean isWrite) {
        if (isWrite || dataSourceSlaves == null || dataSourceSlaves.size() == 0) {
            return dataSource;
        } else {
            if (dataSourceSlaves.size() == 1) {
                return dataSourceSlaves.get(0);
            } else {
                int rd = random.nextInt(dataSourceSlaves.size());
                return dataSourceSlaves.get(rd);
            }
        }
    }

    //private static final String RETURN_RESULT_SET_PREFIX = "#result-set-";

    //private static final String RETURN_UPDATE_COUNT_PREFIX = "#update-count-";

    /** Custom NativeJdbcExtractor */
    private NativeJdbcExtractor nativeJdbcExtractor;

    /** If this variable is false, we will throw exceptions on SQL warnings */
    private boolean ignoreWarnings = true;

    /**
     * If this variable is set to a non-zero value, it will be used for setting the
     * fetchSize property on statements used for query processing.
     */
    private int fetchSize = 0;

    /**
     * If this variable is set to a non-zero value, it will be used for setting the
     * maxRows property on statements used for query processing.
     */
    private int maxRows = 0;

    /**
     * If this variable is set to a non-zero value, it will be used for setting the
     * queryTimeout property on statements used for query processing.
     */
    private int queryTimeout = 0;

    /**
     * If this variable is set to true then all results checking will be bypassed for any
     * callable statement processing.  This can be used to avoid a bug in some older Oracle
     * JDBC drivers like 10.1.0.2.
     */
    private boolean skipResultsProcessing = false;

    /**
     * If this variable is set to true then all results from a stored procedure call
     * that don't have a corresponding SqlOutParameter declaration will be bypassed.
     * All other results processng will be take place unless the variable 
     * <code>skipResultsProcessing</code> is set to <code>true</code> 
     */
    private boolean skipUndeclaredResults = false;

    /**
     * If this variable is set to true then execution of a CallableStatement will return
     * the results in a Map that uses case insensitive names for the parameters if
     * Commons Collections is available on the classpath.
     */
    private boolean resultsMapCaseInsensitive = false;

    /**
     * Construct a new JdbcTemplate for bean usage.
     * <p>Note: The DataSource has to be set before using the instance.
     * @see #setDataSource
     */
    public JdbcTemplate() {
        //checkHealthy();
    }

    /**
     * Construct a new JdbcTemplate, given a DataSource to obtain connections from.
     * <p>Note: This will not trigger initialization of the exception translator.
     * @param dataSource the JDBC DataSource to obtain connections from
     */
    public JdbcTemplate(DataSource dataSource) {
        //setDataSource(dataSource);
        afterPropertiesSet(dataSource);
        //checkHealthy();
    }

    /**
     * Construct a new JdbcTemplate, given a DataSource to obtain connections from.
     * <p>Note: Depending on the "lazyInit" flag, initialization of the exception translator
     * will be triggered.
     * @param dataSource the JDBC DataSource to obtain connections from
     * @param lazyInit whether to lazily initialize the SQLExceptionTranslator
     */
    public JdbcTemplate(DataSource dataSource, boolean lazyInit) {
        //setDataSource(dataSource);
        setLazyInit(lazyInit);
        afterPropertiesSet(dataSource);
        //checkHealthy();
    }

    /**
     * Set a NativeJdbcExtractor to extract native JDBC objects from wrapped handles.
     * Useful if native Statement and/or ResultSet handles are expected for casting
     * to database-specific implementation classes, but a connection pool that wraps
     * JDBC objects is used (note: <i>any</i> pool will return wrapped Connections).
     */
    public void setNativeJdbcExtractor(NativeJdbcExtractor extractor) {
        this.nativeJdbcExtractor = extractor;
    }

    /**
     * Return the current NativeJdbcExtractor implementation.
     */
    public NativeJdbcExtractor getNativeJdbcExtractor() {
        return this.nativeJdbcExtractor;
    }

    /**
     * Set whether or not we want to ignore SQLWarnings.
     * <p>Default is "true", swallowing and logging all warnings. Switch this flag
     * to "false" to make the JdbcTemplate throw a SQLWarningException instead.
     * @see java.sql.SQLWarning
     * @see org.springframework.jdbc.SQLWarningException
     * @see #handleWarnings
     */
    public void setIgnoreWarnings(boolean ignoreWarnings) {
        this.ignoreWarnings = ignoreWarnings;
    }

    /**
     * Return whether or not we ignore SQLWarnings.
     */
    public boolean isIgnoreWarnings() {
        return this.ignoreWarnings;
    }

    /**
     * Set the fetch size for this JdbcTemplate. This is important for processing
     * large result sets: Setting this higher than the default value will increase
     * processing speed at the cost of memory consumption; setting this lower can
     * avoid transferring row data that will never be read by the application.
     * <p>Default is 0, indicating to use the JDBC driver's default.
     * @see java.sql.Statement#setFetchSize
     */
    public void setFetchSize(int fetchSize) {
        this.fetchSize = fetchSize;
    }

    /**
     * Return the fetch size specified for this JdbcTemplate.
     */
    public int getFetchSize() {
        return this.fetchSize;
    }

    /**
     * Set the maximum number of rows for this JdbcTemplate. This is important
     * for processing subsets of large result sets, avoiding to read and hold
     * the entire result set in the database or in the JDBC driver if we're
     * never interested in the entire result in the first place (for example,
     * when performing searches that might return a large number of matches).
     * <p>Default is 0, indicating to use the JDBC driver's default.
     * @see java.sql.Statement#setMaxRows
     */
    public void setMaxRows(int maxRows) {
        this.maxRows = maxRows;
    }

    /**
     * Return the maximum number of rows specified for this JdbcTemplate.
     */
    public int getMaxRows() {
        return this.maxRows;
    }

    /**
     * Set the query timeout for statements that this JdbcTemplate executes.
     * <p>Default is 0, indicating to use the JDBC driver's default.
     * <p>Note: Any timeout specified here will be overridden by the remaining
     * transaction timeout when executing within a transaction that has a
     * timeout specified at the transaction level.
     * @see java.sql.Statement#setQueryTimeout
     */
    public void setQueryTimeout(int queryTimeout) {
        this.queryTimeout = queryTimeout;
    }

    /**
     * Return the query timeout for statements that this JdbcTemplate executes.
     */
    public int getQueryTimeout() {
        return this.queryTimeout;
    }

    /**
     * Set whether results processing should be skipped.  Can be used to optimize callable
     * statement processing when we know that no results are being passed back - the processing
     * of out parameter will still take place.  This can be used to avoid a bug in some older
     * Oracle JDBC drivers like 10.1.0.2.
     */
    public void setSkipResultsProcessing(boolean skipResultsProcessing) {
        this.skipResultsProcessing = skipResultsProcessing;
    }

    /**
     * Return whether results processing should be skipped.
     */
    public boolean isSkipResultsProcessing() {
        return this.skipResultsProcessing;
    }

    /**
     * Set whether undelared results should be skipped.
     */
    public void setSkipUndeclaredResults(boolean skipUndeclaredResults) {
        this.skipUndeclaredResults = skipUndeclaredResults;
    }

    /**
     * Return whether undeclared results should be skipped.
     */
    public boolean isSkipUndeclaredResults() {
        return this.skipUndeclaredResults;
    }

    /**
     * Set whether execution of a CallableStatement will return the results in a Map
     * that uses case insensitive names for the parameters.
     */
    public void setResultsMapCaseInsensitive(boolean resultsMapCaseInsensitive) {
        this.resultsMapCaseInsensitive = resultsMapCaseInsensitive;
    }

    /**
     * Return whether execution of a CallableStatement will return the results in a Map
     * that uses case insensitive names for the parameters.
     */
    public boolean isResultsMapCaseInsensitive() {
        return this.resultsMapCaseInsensitive;
    }

    //-------------------------------------------------------------------------
    // Methods dealing with a plain java.sql.Connection
    //-------------------------------------------------------------------------

    /**
     * Return the exception translator for this instance.
     * <p>Creates a default {@link SQLErrorCodeSQLExceptionTranslator}
     * for the specified DataSource if none set, or a
     * {@link SQLStateSQLExceptionTranslator} in case of no DataSource.
     * @see #getDataSource()
     */
    public SQLExceptionTranslator getExceptionTranslator(DataSource dataSource) {
        SQLExceptionTranslator e = exceptionTranslators.get(dataSource);
        synchronized (exceptionTranslators) {
            if (e == null) {
                if (dataSource != null) {
                    e = new SQLErrorCodeSQLExceptionTranslator(dataSource);
                } else {
                    e = new SQLStateSQLExceptionTranslator();
                }
                exceptionTranslators.put(dataSource, e);
            }
        }

        return e;
    }

    /**
     * Create a close-suppressing proxy for the given JDBC Connection.
     * Called by the <code>execute</code> method.
     * <p>The proxy also prepares returned JDBC Statements, applying
     * statement settings such as fetch size, max rows, and query timeout.
     * @param con the JDBC Connection to create a proxy for
     * @return the Connection proxy
     * @see java.sql.Connection#close()
     * @see #execute(ConnectionCallback)
     * @see #applyStatementSettings
     */
    protected Connection createConnectionProxy(DataSource dataSource, Connection con) {
        return (Connection) Proxy.newProxyInstance(ConnectionProxy.class.getClassLoader(),
                new Class[] { ConnectionProxy.class }, new CloseSuppressingInvocationHandler(dataSource, con));
    }

    //-------------------------------------------------------------------------
    // Methods dealing with static SQL (java.sql.Statement)
    //-------------------------------------------------------------------------

    public Object execute(StatementCallback action, boolean isWrite) throws DataAccessException {
        Assert.notNull(action, "Callback object must not be null");

        long start = System.currentTimeMillis();

        DataSource ds = getDataSource(isWrite);
        Connection con = safeGetConnection(ds, isWrite);
        Statement stmt = null;
        try {
            Connection conToUse = con;
            if (this.nativeJdbcExtractor != null
                    && this.nativeJdbcExtractor.isNativeConnectionNecessaryForNativeStatements()) {
                conToUse = this.nativeJdbcExtractor.getNativeConnection(con);
            }
            stmt = conToUse.createStatement();
            applyStatementSettings(ds, stmt);
            Statement stmtToUse = stmt;
            if (this.nativeJdbcExtractor != null) {
                stmtToUse = this.nativeJdbcExtractor.getNativeStatement(stmt);
            }
            Object result = action.doInStatement(stmtToUse);
            handleWarnings(stmt);
            return result;
        } catch (Exception ex) {
            // Release Connection early, to avoid potential connection pool deadlock
            // in the case when the exception translator hasn't been initialized yet.
            JdbcUtils.closeStatement(stmt);
            stmt = null;
            DataSourceUtils.releaseConnection(con, ds);
            con = null;
            if (ex instanceof SQLException) {
                throw getExceptionTranslator(ds).translate("StatementCallback", getSql(action), (SQLException) ex);
            } else {
                throw new RuntimeException("StatementCallback " + getSql(action), ex);
            }
        } finally {
            JdbcUtils.closeStatement(stmt);
            DataSourceUtils.releaseConnection(con, ds);

            //add slow log
            long useTime = System.currentTimeMillis() - start;
            if (useTime > ApiLogger.DB_FIRE_TIME) {
                ApiLogger.fire(new StringBuffer().append("DB ")
                        .append(((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl()).append(" too slow :")
                        .append(useTime).append(" isWrite:").append(isWrite));
            }

            TimeStatUtil.addElapseTimeStat(resource, isWrite, start, useTime);
        }
    }

    /**
     * try 3 times to get connection
     * @param ds
     * @return
     * @throws CannotGetJdbcConnectionException
     */
    private Connection safeGetConnection(DataSource ds, boolean isWrite) throws CannotGetJdbcConnectionException {
        Connection con = null;
        int retryCount, count;
        retryCount = count = (isWrite ? writeTryGetConCount : readTryGetConCount);
        while (count-- > 0) {
            try {
                con = DataSourceUtils.getConnection(ds);
                return con;
            } catch (CannotGetJdbcConnectionException e) {
                ApiLogger.info(new StringBuilder(64).append("get connection try count:")
                        .append((retryCount - count)).append(", ds=")
                        .append(((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl()));
                DataSourceUtils.releaseConnection(con, ds);
            }
        }

        ApiLogger.fire(new StringBuffer().append("DB ")
                .append(((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl()).append(" Error:")
                .append("Could not get JDBC Connection: "));
        throw new CannotGetJdbcConnectionException("Could not get JDBC Connection: " + ", ds="
                + ((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl(), new SQLException());
    }

    public Object query(final String sql, final ResultSetExtractor rse) throws DataAccessException {
        Assert.notNull(sql, "SQL must not be null");
        Assert.notNull(rse, "ResultSetExtractor must not be null");
        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace(new StringBuilder(64).append("Executing SQL query [").append(sql).append("]"));
        }

        class QueryStatementCallback implements StatementCallback, SqlProvider {
            public Object doInStatement(Statement stmt) throws SQLException {
                ResultSet rs = null;
                try {
                    rs = stmt.executeQuery(sql);
                    ResultSet rsToUse = rs;
                    if (nativeJdbcExtractor != null) {
                        rsToUse = nativeJdbcExtractor.getNativeResultSet(rs);
                    }
                    return rse.extractData(rsToUse);
                } finally {
                    JdbcUtils.closeResultSet(rs);
                }
            }

            public String getSql() {
                return sql;
            }
        }
        return execute(new QueryStatementCallback(), false);
    }

    public void query(String sql, RowCallbackHandler rch) throws DataAccessException {
        query(sql, new RowCallbackHandlerResultSetExtractor(rch));
    }

    @SuppressWarnings("unchecked")
    public List query(String sql, RowMapper rowMapper) throws DataAccessException {
        return (List) query(sql, new RowMapperResultSetExtractor(rowMapper));
    }

    @SuppressWarnings("unchecked")
    public Map queryForMap(String sql) throws DataAccessException {
        return (Map) queryForObject(sql, getColumnMapRowMapper());
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, RowMapper rowMapper) throws DataAccessException {
        List results = query(sql, rowMapper);
        return DataAccessUtils.requiredSingleResult(results);
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, Class requiredType) throws DataAccessException {
        return queryForObject(sql, getSingleColumnRowMapper(requiredType));
    }

    public long queryForLong(String sql) throws DataAccessException {
        Number number = (Number) queryForObject(sql, Long.class);
        return (number != null ? number.longValue() : 0);
    }

    public int queryForInt(String sql) throws DataAccessException {
        Number number = (Number) queryForObject(sql, Integer.class);
        return (number != null ? number.intValue() : 0);
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql, Class elementType) throws DataAccessException {
        return query(sql, getSingleColumnRowMapper(elementType));
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql) throws DataAccessException {
        return query(sql, getColumnMapRowMapper());
    }

    public SqlRowSet queryForRowSet(String sql) throws DataAccessException {
        return (SqlRowSet) query(sql, new SqlRowSetResultSetExtractor());
    }

    public int update(final String sql) throws DataAccessException {
        Assert.notNull(sql, "SQL must not be null");
        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace(new StringBuilder(64).append("Executing SQL update [").append(sql).append("]"));
        }

        class UpdateStatementCallback implements StatementCallback, SqlProvider {
            public Object doInStatement(Statement stmt) throws SQLException {
                int rows = stmt.executeUpdate(sql);
                if (ApiLogger.isTraceEnabled()) {
                    ApiLogger.trace(
                            new StringBuilder(64).append("SQL update affected ").append(rows).append(" rows"));
                }
                return new Integer(rows);
            }

            public String getSql() {
                return sql;
            }
        }
        return ((Integer) execute(new UpdateStatementCallback(), true)).intValue();
    }

    public int[] batchUpdate(final String[] sql) throws DataAccessException {
        Assert.notEmpty(sql, "SQL array must not be empty");
        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace(new StringBuilder(128).append("Executing SQL batch update of ").append(sql.length)
                    .append(" statements"));
        }

        class BatchUpdateStatementCallback implements StatementCallback, SqlProvider {
            private String currSql;

            public Object doInStatement(Statement stmt) throws SQLException, DataAccessException {
                int[] rowsAffected = new int[sql.length];
                if (JdbcUtils.supportsBatchUpdates(stmt.getConnection())) {
                    for (int i = 0; i < sql.length; i++) {
                        this.currSql = sql[i];
                        stmt.addBatch(sql[i]);
                    }
                    rowsAffected = stmt.executeBatch();
                } else {
                    for (int i = 0; i < sql.length; i++) {
                        this.currSql = sql[i];
                        if (!stmt.execute(sql[i])) {
                            rowsAffected[i] = stmt.getUpdateCount();
                        } else {
                            throw new InvalidDataAccessApiUsageException("Invalid batch SQL statement: " + sql[i]);
                        }
                    }
                }
                return rowsAffected;
            }

            public String getSql() {
                return currSql;
            }
        }
        return (int[]) execute(new BatchUpdateStatementCallback(), true);
    }

    //-------------------------------------------------------------------------
    // Methods dealing with prepared statements
    //-------------------------------------------------------------------------

    public Object execute(PreparedStatementCreator psc, PreparedStatementCallback action, boolean isWrite)
            throws DataAccessException {

        Assert.notNull(psc, "PreparedStatementCreator must not be null");
        Assert.notNull(action, "Callback object must not be null");
        if (ApiLogger.isTraceEnabled()) {
            String sql = getSql(psc);
            ApiLogger.trace(new StringBuilder(128).append("Executing prepared SQL statement")
                    .append((sql != null ? " [" + sql + "]" : "")));
        }

        long start = System.currentTimeMillis();
        DataSource ds = getDataSource(isWrite);
        Connection con = safeGetConnection(ds, isWrite);
        PreparedStatement ps = null;
        try {
            Connection conToUse = con;
            if (this.nativeJdbcExtractor != null
                    && this.nativeJdbcExtractor.isNativeConnectionNecessaryForNativePreparedStatements()) {
                conToUse = this.nativeJdbcExtractor.getNativeConnection(con);
            }
            ps = psc.createPreparedStatement(conToUse);
            applyStatementSettings(ds, ps);
            PreparedStatement psToUse = ps;
            if (this.nativeJdbcExtractor != null) {
                psToUse = this.nativeJdbcExtractor.getNativePreparedStatement(ps);
            }
            Object result = action.doInPreparedStatement(psToUse);
            handleWarnings(ps);
            return result;
        } catch (Exception ex) {
            // Release Connection early, to avoid potential connection pool deadlock
            // in the case when the exception translator hasn't been initialized yet.
            if (psc instanceof ParameterDisposer) {
                ((ParameterDisposer) psc).cleanupParameters();
            }
            String sql = getSql(psc);
            psc = null;
            JdbcUtils.closeStatement(ps);
            ps = null;
            DataSourceUtils.releaseConnection(con, ds);
            con = null;
            if (ex instanceof SQLException) {
                throw getExceptionTranslator(ds).translate("PreparedStatementCallback", sql, (SQLException) ex);
            } else {
                throw new RuntimeException("PreparedStatementCallback " + getSql(psc), ex);
            }
        } finally {

            //add slow log
            long useTime = System.currentTimeMillis() - start;
            if (useTime > ApiLogger.DB_FIRE_TIME) {
                ApiLogger.fire(new StringBuffer().append("DB ")
                        .append(((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl()).append(" too slow :")
                        .append(useTime).append(" isWrite:").append(isWrite));
            }

            if (psc instanceof ParameterDisposer) {
                ((ParameterDisposer) psc).cleanupParameters();
            }
            JdbcUtils.closeStatement(ps);
            DataSourceUtils.releaseConnection(con, ds);

            TimeStatUtil.addElapseTimeStat(resource, isWrite, start, useTime);
        }
    }

    public Object execute(String sql, PreparedStatementCallback action, boolean isWrite)
            throws DataAccessException {
        return execute(new SimplePreparedStatementCreator(sql), action, isWrite);
    }

    /**
     * Query using a prepared statement, allowing for a PreparedStatementCreator
     * and a PreparedStatementSetter. Most other query methods use this method,
     * but application code will always work with either a creator or a setter.
     * @param psc Callback handler that can create a PreparedStatement given a
     * Connection
     * @param pss object that knows how to set values on the prepared statement.
     * If this is null, the SQL will be assumed to contain no bind parameters.
     * @param rse object that will extract results.
     * @return an arbitrary result object, as returned by the ResultSetExtractor
     * @throws DataAccessException if there is any problem
     */
    public Object query(PreparedStatementCreator psc, final PreparedStatementSetter pss,
            final ResultSetExtractor rse) throws DataAccessException {

        Assert.notNull(rse, "ResultSetExtractor must not be null");
        if (ApiLogger.isTraceEnabled())
            ApiLogger.trace("Executing prepared SQL query");

        return execute(psc, new PreparedStatementCallback() {
            public Object doInPreparedStatement(PreparedStatement ps) throws SQLException {
                ResultSet rs = null;
                try {
                    if (pss != null) {
                        pss.setValues(ps);
                    }
                    rs = ps.executeQuery();
                    ResultSet rsToUse = rs;
                    if (nativeJdbcExtractor != null) {
                        rsToUse = nativeJdbcExtractor.getNativeResultSet(rs);
                    }
                    return rse.extractData(rsToUse);
                } finally {
                    JdbcUtils.closeResultSet(rs);
                    if (pss instanceof ParameterDisposer) {
                        ((ParameterDisposer) pss).cleanupParameters();
                    }
                }
            }
        }, false);
    }

    public Object query(PreparedStatementCreator psc, ResultSetExtractor rse) throws DataAccessException {
        return query(psc, null, rse);
    }

    public Object query(String sql, PreparedStatementSetter pss, ResultSetExtractor rse)
            throws DataAccessException {
        return query(new SimplePreparedStatementCreator(sql), pss, rse);
    }

    public Object query(String sql, Object[] args, int[] argTypes, ResultSetExtractor rse)
            throws DataAccessException {
        return query(sql, new ArgTypePreparedStatementSetter(args, argTypes), rse);
    }

    public Object query(String sql, Object[] args, ResultSetExtractor rse) throws DataAccessException {
        return query(sql, new ArgPreparedStatementSetter(args), rse);
    }

    public void query(PreparedStatementCreator psc, RowCallbackHandler rch) throws DataAccessException {
        query(psc, new RowCallbackHandlerResultSetExtractor(rch));
    }

    public void query(String sql, PreparedStatementSetter pss, RowCallbackHandler rch) throws DataAccessException {
        query(sql, pss, new RowCallbackHandlerResultSetExtractor(rch));
    }

    public void query(String sql, Object[] args, int[] argTypes, RowCallbackHandler rch)
            throws DataAccessException {
        query(sql, new ArgTypePreparedStatementSetter(args, argTypes), rch);
    }

    public void query(String sql, Object[] args, RowCallbackHandler rch) throws DataAccessException {
        query(sql, new ArgPreparedStatementSetter(args), rch);
    }

    @SuppressWarnings("unchecked")
    public List query(PreparedStatementCreator psc, RowMapper rowMapper) throws DataAccessException {
        return (List) query(psc, new RowMapperResultSetExtractor(rowMapper));
    }

    @SuppressWarnings("unchecked")
    public List query(String sql, PreparedStatementSetter pss, RowMapper rowMapper) throws DataAccessException {
        return (List) query(sql, pss, new RowMapperResultSetExtractor(rowMapper));
    }

    @SuppressWarnings("unchecked")
    public List query(String sql, Object[] args, int[] argTypes, RowMapper rowMapper) throws DataAccessException {
        return (List) query(sql, args, argTypes, new RowMapperResultSetExtractor(rowMapper));
    }

    @SuppressWarnings("unchecked")
    public List query(String sql, Object[] args, RowMapper rowMapper) throws DataAccessException {
        return (List) query(sql, args, new RowMapperResultSetExtractor(rowMapper));
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, Object[] args, int[] argTypes, RowMapper rowMapper)
            throws DataAccessException {

        List results = (List) query(sql, args, argTypes, new RowMapperResultSetExtractor(rowMapper, 1));
        return DataAccessUtils.requiredSingleResult(results);
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, Object[] args, RowMapper rowMapper) throws DataAccessException {
        List results = (List) query(sql, args, new RowMapperResultSetExtractor(rowMapper, 1));
        return DataAccessUtils.requiredSingleResult(results);
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, Object[] args, int[] argTypes, Class requiredType)
            throws DataAccessException {

        return queryForObject(sql, args, argTypes, getSingleColumnRowMapper(requiredType));
    }

    @SuppressWarnings("unchecked")
    public Object queryForObject(String sql, Object[] args, Class requiredType) throws DataAccessException {
        return queryForObject(sql, args, getSingleColumnRowMapper(requiredType));
    }

    @SuppressWarnings("unchecked")
    public Map queryForMap(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        return (Map) queryForObject(sql, args, argTypes, getColumnMapRowMapper());
    }

    @SuppressWarnings("unchecked")
    public Map queryForMap(String sql, Object[] args) throws DataAccessException {
        return (Map) queryForObject(sql, args, getColumnMapRowMapper());
    }

    public long queryForLong(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        Number number = (Number) queryForObject(sql, args, argTypes, Long.class);
        return (number != null ? number.longValue() : 0);
    }

    public long queryForLong(String sql, Object[] args) throws DataAccessException {
        Number number = (Number) queryForObject(sql, args, Long.class);
        return (number != null ? number.longValue() : 0);
    }

    public int queryForInt(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        Number number = (Number) queryForObject(sql, args, argTypes, Integer.class);
        return (number != null ? number.intValue() : 0);
    }

    public int queryForInt(String sql, Object[] args) throws DataAccessException {
        Number number = (Number) queryForObject(sql, args, Integer.class);
        return (number != null ? number.intValue() : 0);
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql, Object[] args, int[] argTypes, Class elementType)
            throws DataAccessException {
        return query(sql, args, argTypes, getSingleColumnRowMapper(elementType));
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql, Object[] args, Class elementType) throws DataAccessException {
        return query(sql, args, getSingleColumnRowMapper(elementType));
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        return query(sql, args, argTypes, getColumnMapRowMapper());
    }

    @SuppressWarnings("unchecked")
    public List queryForList(String sql, Object[] args) throws DataAccessException {
        return query(sql, args, getColumnMapRowMapper());
    }

    public SqlRowSet queryForRowSet(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        return (SqlRowSet) query(sql, args, argTypes, new SqlRowSetResultSetExtractor());
    }

    public SqlRowSet queryForRowSet(String sql, Object[] args) throws DataAccessException {
        return (SqlRowSet) query(sql, args, new SqlRowSetResultSetExtractor());
    }

    protected int update(final PreparedStatementCreator psc, final PreparedStatementSetter pss)
            throws DataAccessException {

        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace("Executing prepared SQL update");
        }

        Integer result = (Integer) execute(psc, new PreparedStatementCallback() {
            public Object doInPreparedStatement(PreparedStatement ps) throws SQLException {
                try {
                    if (pss != null) {
                        pss.setValues(ps);
                    }
                    int rows = ps.executeUpdate();
                    if (ApiLogger.isTraceEnabled()) {
                        ApiLogger.trace("SQL update affected " + rows + " rows");
                    }
                    return new Integer(rows);
                } finally {
                    if (pss instanceof ParameterDisposer) {
                        ((ParameterDisposer) pss).cleanupParameters();
                    }
                }
            }
        }, true);
        return result.intValue();
    }

    public int update(PreparedStatementCreator psc) throws DataAccessException {
        return update(psc, (PreparedStatementSetter) null);
    }

    @SuppressWarnings("unchecked")
    public int update(final PreparedStatementCreator psc, final KeyHolder generatedKeyHolder)
            throws DataAccessException {

        Assert.notNull(generatedKeyHolder, "KeyHolder must not be null");
        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace("Executing SQL update and returning generated keys");
        }

        Integer result = (Integer) execute(psc, new PreparedStatementCallback() {
            public Object doInPreparedStatement(PreparedStatement ps) throws SQLException {
                int rows = ps.executeUpdate();
                List generatedKeys = generatedKeyHolder.getKeyList();
                generatedKeys.clear();
                ResultSet keys = ps.getGeneratedKeys();
                if (keys != null) {
                    try {
                        RowMapper rowMapper = getColumnMapRowMapper();
                        RowMapperResultSetExtractor rse = new RowMapperResultSetExtractor(rowMapper, 1);
                        generatedKeys.addAll((List) rse.extractData(keys));
                    } finally {
                        JdbcUtils.closeResultSet(keys);
                    }
                }
                if (ApiLogger.isTraceEnabled()) {
                    ApiLogger.trace(
                            "SQL update affected " + rows + " rows and returned " + generatedKeys.size() + " keys");
                }
                return new Integer(rows);
            }
        }, true);
        return result.intValue();
    }

    public int update(String sql, PreparedStatementSetter pss) throws DataAccessException {
        return update(new SimplePreparedStatementCreator(sql), pss);
    }

    public int update(String sql, Object[] args, int[] argTypes) throws DataAccessException {
        return update(sql, new ArgTypePreparedStatementSetter(args, argTypes));
    }

    public int update(String sql, Object[] args) throws DataAccessException {
        return update(sql, new ArgPreparedStatementSetter(args));
    }

    @SuppressWarnings("unchecked")
    public int[] batchUpdate(String sql, final BatchPreparedStatementSetter pss) throws DataAccessException {
        if (ApiLogger.isTraceEnabled()) {
            ApiLogger.trace("Executing SQL batch update [" + sql + "]");
        }

        return (int[]) execute(sql, new PreparedStatementCallback() {
            public Object doInPreparedStatement(PreparedStatement ps) throws SQLException {
                try {
                    int batchSize = pss.getBatchSize();
                    InterruptibleBatchPreparedStatementSetter ipss = (pss instanceof InterruptibleBatchPreparedStatementSetter
                            ? (InterruptibleBatchPreparedStatementSetter) pss
                            : null);
                    if (JdbcUtils.supportsBatchUpdates(ps.getConnection())) {
                        for (int i = 0; i < batchSize; i++) {
                            pss.setValues(ps, i);
                            if (ipss != null && ipss.isBatchExhausted(i)) {
                                break;
                            }
                            ps.addBatch();
                        }
                        return ps.executeBatch();
                    } else {
                        List rowsAffected = new ArrayList();
                        for (int i = 0; i < batchSize; i++) {
                            pss.setValues(ps, i);
                            if (ipss != null && ipss.isBatchExhausted(i)) {
                                break;
                            }
                            rowsAffected.add(new Integer(ps.executeUpdate()));
                        }
                        int[] rowsAffectedArray = new int[rowsAffected.size()];
                        for (int i = 0; i < rowsAffectedArray.length; i++) {
                            rowsAffectedArray[i] = ((Integer) rowsAffected.get(i)).intValue();
                        }
                        return rowsAffectedArray;
                    }
                } finally {
                    if (pss instanceof ParameterDisposer) {
                        ((ParameterDisposer) pss).cleanupParameters();
                    }
                }
            }
        }, true);
    }

    //-------------------------------------------------------------------------
    // Methods dealing with callable statements
    //-------------------------------------------------------------------------

    public Object execute(CallableStatementCreator csc, CallableStatementCallback action, boolean isWrite)
            throws DataAccessException {

        Assert.notNull(csc, "CallableStatementCreator must not be null");
        Assert.notNull(action, "Callback object must not be null");
        if (ApiLogger.isTraceEnabled()) {
            String sql = getSql(csc);
            ApiLogger.trace("Calling stored procedure" + (sql != null ? " [" + sql + "]" : ""));
        }

        long start = System.currentTimeMillis();
        DataSource ds = getDataSource(isWrite);
        Connection con = safeGetConnection(ds, isWrite);
        CallableStatement cs = null;
        try {
            Connection conToUse = con;
            if (this.nativeJdbcExtractor != null) {
                conToUse = this.nativeJdbcExtractor.getNativeConnection(con);
            }
            cs = csc.createCallableStatement(conToUse);
            applyStatementSettings(ds, cs);
            CallableStatement csToUse = cs;
            if (this.nativeJdbcExtractor != null) {
                csToUse = this.nativeJdbcExtractor.getNativeCallableStatement(cs);
            }
            Object result = action.doInCallableStatement(csToUse);
            handleWarnings(cs);
            return result;
        } catch (Exception ex) {
            // Release Connection early, to avoid potential connection pool deadlock
            // in the case when the exception translator hasn't been initialized yet.
            if (csc instanceof ParameterDisposer) {
                ((ParameterDisposer) csc).cleanupParameters();
            }
            String sql = getSql(csc);
            csc = null;
            JdbcUtils.closeStatement(cs);
            cs = null;
            DataSourceUtils.releaseConnection(con, ds);
            con = null;
            if (ex instanceof SQLException) {
                throw getExceptionTranslator(ds).translate("CallableStatementCallback", sql, (SQLException) ex);
            } else {
                throw new RuntimeException("CallableStatementCallback " + getSql(csc), ex);
            }
        } finally {
            //add slow log
            long useTime = System.currentTimeMillis() - start;
            if (useTime > ApiLogger.DB_FIRE_TIME) {
                ApiLogger.fire(new StringBuffer().append("DB ")
                        .append(((com.mchange.v2.c3p0.ComboPooledDataSource) ds).getJdbcUrl()).append(" too slow :")
                        .append(useTime).append(" isWrite:").append(isWrite));
            }

            if (csc instanceof ParameterDisposer) {
                ((ParameterDisposer) csc).cleanupParameters();
            }
            JdbcUtils.closeStatement(cs);
            DataSourceUtils.releaseConnection(con, ds);

            TimeStatUtil.addElapseTimeStat(resource, isWrite, start, useTime);
        }
    }

    /**
     * Extract output parameters from the completed stored procedure.
     * @param cs JDBC wrapper for the stored procedure
     * @param parameters parameter list for the stored procedure
     * @return Map that contains returned results
     */
    @SuppressWarnings("unchecked")
    protected Map extractOutputParameters(CallableStatement cs, List parameters) throws SQLException {
        Map returnedResults = new HashMap();
        int sqlColIndex = 1;
        for (int i = 0; i < parameters.size(); i++) {
            SqlParameter param = (SqlParameter) parameters.get(i);
            if (param instanceof SqlOutParameter) {
                SqlOutParameter outParam = (SqlOutParameter) param;
                if (outParam.isReturnTypeSupported()) {
                    Object out = outParam.getSqlReturnType().getTypeValue(cs, sqlColIndex, outParam.getSqlType(),
                            outParam.getTypeName());
                    returnedResults.put(outParam.getName(), out);
                } else {
                    Object out = cs.getObject(sqlColIndex);
                    if (out instanceof ResultSet) {
                        if (outParam.isResultSetSupported()) {
                            returnedResults.putAll(processResultSet((ResultSet) out, outParam));
                        } else {
                            String rsName = outParam.getName();
                            SqlReturnResultSet rsParam = new SqlReturnResultSet(rsName, new ColumnMapRowMapper());
                            returnedResults.putAll(processResultSet(cs.getResultSet(), rsParam));
                            ApiLogger.info("Added default SqlReturnResultSet parameter named " + rsName);
                        }
                    } else {
                        returnedResults.put(outParam.getName(), out);
                    }
                }
            }
            if (!(param.isResultsParameter())) {
                sqlColIndex++;
            }
        }
        return returnedResults;
    }

    /**
     * Process the given ResultSet from a stored procedure.
     * @param rs the ResultSet to process
     * @param param the corresponding stored procedure parameter
     * @return Map that contains returned results
     */
    @SuppressWarnings("unchecked")
    protected Map processResultSet(ResultSet rs, ResultSetSupportingSqlParameter param) throws SQLException {
        if (rs == null) {
            return Collections.EMPTY_MAP;
        }
        Map returnedResults = new HashMap();
        try {
            ResultSet rsToUse = rs;
            if (this.nativeJdbcExtractor != null) {
                rsToUse = this.nativeJdbcExtractor.getNativeResultSet(rs);
            }
            if (param.getRowMapper() != null) {
                RowMapper rowMapper = param.getRowMapper();
                Object result = (new RowMapperResultSetExtractor(rowMapper)).extractData(rsToUse);
                returnedResults.put(param.getName(), result);
            } else if (param.getRowCallbackHandler() != null) {
                RowCallbackHandler rch = param.getRowCallbackHandler();
                (new RowCallbackHandlerResultSetExtractor(rch)).extractData(rsToUse);
                returnedResults.put(param.getName(), "ResultSet returned from stored procedure was processed");
            } else if (param.getResultSetExtractor() != null) {
                Object result = param.getResultSetExtractor().extractData(rsToUse);
                returnedResults.put(param.getName(), result);
            }
        } finally {
            JdbcUtils.closeResultSet(rs);
        }
        return returnedResults;
    }

    //-------------------------------------------------------------------------
    // Implementation hooks and helper methods
    //-------------------------------------------------------------------------

    /**
     * Create a new RowMapper for reading columns as key-value pairs.
     * @return the RowMapper to use
     * @see ColumnMapRowMapper
     */
    protected RowMapper getColumnMapRowMapper() {
        return new ColumnMapRowMapper();
    }

    /**
     * Create a new RowMapper for reading result objects from a single column.
     * @param requiredType the type that each result object is expected to match
     * @return the RowMapper to use
     * @see SingleColumnRowMapper
     */
    @SuppressWarnings("unchecked")
    protected RowMapper getSingleColumnRowMapper(Class requiredType) {
        return new SingleColumnRowMapper(requiredType);
    }

    /**
     * Create a Map instance to be used as results map.
     * <p>If "isResultsMapCaseInsensitive" has been set to true, a linked case-insensitive Map
     * will be created if possible, else a plain HashMap (see Spring's CollectionFactory).
     * @return the results Map instance
     * @see #setResultsMapCaseInsensitive
     * @see org.springframework.core.CollectionFactory#createLinkedCaseInsensitiveMapIfPossible
     */
    @SuppressWarnings("unchecked")
    protected Map createResultsMap() {
        if (isResultsMapCaseInsensitive()) {
            return CollectionFactory.createLinkedCaseInsensitiveMapIfPossible(10);
        } else {
            return new LinkedHashMap();
        }
    }

    /**
     * Prepare the given JDBC Statement (or PreparedStatement or CallableStatement),
     * applying statement settings such as fetch size, max rows, and query timeout.
     * @param stmt the JDBC Statement to prepare
     * @throws SQLException if thrown by JDBC API
     * @see #setFetchSize
     * @see #setMaxRows
     * @see #setQueryTimeout
     * @see org.springframework.jdbc.datasource.DataSourceUtils#applyTransactionTimeout
     */
    protected void applyStatementSettings(DataSource dataSource, Statement stmt) throws SQLException {
        int fetchSize = getFetchSize();
        if (fetchSize > 0) {
            stmt.setFetchSize(fetchSize);
        }
        int maxRows = getMaxRows();
        if (maxRows > 0) {
            stmt.setMaxRows(maxRows);
        }
        DataSourceUtils.applyTimeout(stmt, dataSource, getQueryTimeout());
    }

    /**
     * Throw an SQLWarningException if we're not ignoring warnings,
     * else log the warnings (at debug level).
     * @param stmt the current JDBC statement
     * @throws SQLWarningException if not ignoring warnings
     * @see org.springframework.jdbc.SQLWarningException
     */
    protected void handleWarnings(Statement stmt) throws SQLException {
        if (isIgnoreWarnings()) {
            if (ApiLogger.isTraceEnabled()) {
                SQLWarning warningToLog = stmt.getWarnings();
                while (warningToLog != null) {
                    ApiLogger.trace("SQLWarning ignored: SQL state '" + warningToLog.getSQLState()
                            + "', error code '" + warningToLog.getErrorCode() + "', message ["
                            + warningToLog.getMessage() + "]");
                    warningToLog = warningToLog.getNextWarning();
                }
            }
        } else {
            handleWarnings(stmt.getWarnings());
        }
    }

    /**
     * Throw an SQLWarningException if encountering an actual warning.
     * @param warning the warnings object from the current statement.
     * May be <code>null</code>, in which case this method does nothing.
     * @throws SQLWarningException in case of an actual warning to be raised
     */
    protected void handleWarnings(SQLWarning warning) throws SQLWarningException {
        if (warning != null) {
            throw new SQLWarningException("Warning not ignored", warning);
        }
    }

    /**
     * Determine SQL from potential provider object.
     * @param sqlProvider object that's potentially a SqlProvider
     * @return the SQL string, or <code>null</code>
     * @see SqlProvider
     */
    private static String getSql(Object sqlProvider) {
        if (sqlProvider instanceof SqlProvider) {
            return ((SqlProvider) sqlProvider).getSql();
        } else {
            return null;
        }
    }

    /**
     * Invocation handler that suppresses close calls on JDBC COnnections.
     * Also prepares returned Statement (Prepared/CallbackStatement) objects.
     * @see java.sql.Connection#close()
     */
    private class CloseSuppressingInvocationHandler implements InvocationHandler {

        private final Connection target;
        private DataSource dataSource;

        public CloseSuppressingInvocationHandler(DataSource dataSource, Connection target) {
            this.target = target;
            this.dataSource = dataSource;
        }

        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            // Invocation on ConnectionProxy interface coming in...

            if (method.getName().equals("getTargetConnection")) {
                // Handle getTargetConnection method: return underlying Connection.
                return this.target;
            } else if (method.getName().equals("equals")) {
                // Only consider equal when proxies are identical.
                return (proxy == args[0] ? Boolean.TRUE : Boolean.FALSE);
            } else if (method.getName().equals("hashCode")) {
                // Use hashCode of PersistenceManager proxy.
                return new Integer(System.identityHashCode(proxy));
            } else if (method.getName().equals("close")) {
                // Handle close method: suppress, not valid.
                return null;
            }

            // Invoke method on target Connection.
            try {
                Object retVal = method.invoke(this.target, args);

                // If return value is a JDBC Statement, apply statement settings
                // (fetch size, max rows, transaction timeout).
                if (retVal instanceof Statement) {
                    applyStatementSettings(dataSource, ((Statement) retVal));
                }

                return retVal;
            } catch (InvocationTargetException ex) {
                throw ex.getTargetException();
            }
        }
    }

    /**
     * Simple adapter for PreparedStatementCreator, allowing to use a plain SQL statement.
     */
    private static class SimplePreparedStatementCreator implements PreparedStatementCreator, SqlProvider {

        private final String sql;

        public SimplePreparedStatementCreator(String sql) {
            Assert.notNull(sql, "SQL must not be null");
            this.sql = sql;
        }

        public PreparedStatement createPreparedStatement(Connection con) throws SQLException {
            return con.prepareStatement(this.sql);
        }

        public String getSql() {
            return this.sql;
        }
    }

    /**
     * Adapter to enable use of a RowCallbackHandler inside a ResultSetExtractor.
     * <p>Uses a regular ResultSet, so we have to be careful when using it:
     * We don't use it for navigating since this could lead to unpredictable consequences.
     */
    private static class RowCallbackHandlerResultSetExtractor implements ResultSetExtractor {

        private final RowCallbackHandler rch;

        public RowCallbackHandlerResultSetExtractor(RowCallbackHandler rch) {
            this.rch = rch;
        }

        public Object extractData(ResultSet rs) throws SQLException {
            while (rs.next()) {
                this.rch.processRow(rs);
            }
            return null;
        }
    }

}