org.ralasafe.db.JavaBeanColumnAdapter.java Source code

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Here is the source code for org.ralasafe.db.JavaBeanColumnAdapter.java

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/**
 * Copyright (c) 2004-2011 Wang Jinbao(Julian Wong), http://www.ralasafe.com
 * Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
 */
package org.ralasafe.db;

import java.lang.reflect.Method;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.ralasafe.RalasafeException;

/**
 * Mapping a javabean to query result. This adapter adapters resultset to javabean.
 * A query may use where conditions, this adapter adapters javabean to preparedstatement.
 */
public class JavaBeanColumnAdapter implements ColumnAdapter {
    private static Log log = LogFactory.getLog(JavaBeanColumnAdapter.class);

    private String origField;
    private String field;
    private String getterStr;
    private String setterStr;
    private String className;

    private Method setter;
    private Method getter;

    private ResultSetReader rsReader;
    private PstmtSetter pstmtSetter;

    public JavaBeanColumnAdapter(String field, String className) {
        this.origField = field;
        this.field = field.substring(0, 1).toUpperCase() + field.substring(1);
        this.getterStr = "get" + this.field;
        this.setterStr = "set" + this.field;
        this.className = className;

        rsReader = ResultSetReaderUtil.getReader(className);
        pstmtSetter = PstmtSetterUtil.getSetter(className);
    }

    private void initSetterMethod(Object o) throws Exception {
        Class valueClass;
        Class clas = o.getClass();

        if (className.equals("int"))
            valueClass = Integer.TYPE;
        else if (className.equals("float"))
            valueClass = Float.TYPE;
        else if (className.equals("long"))
            valueClass = Long.TYPE;
        else if (className.equals("double"))
            valueClass = Double.TYPE;
        else if (className.equals("boolean"))
            valueClass = Boolean.TYPE;
        else
            valueClass = Class.forName(className);

        setter = clas.getMethod(setterStr, new Class[] { valueClass });
    }

    private void initGetterMethod(Object o) throws Exception {
        Class clas = o.getClass();

        // try getField method first
        try {
            getter = clas.getMethod(getterStr, new Class[] {});
        } catch (NoSuchMethodException e) {
            if ("boolean".equals(className) || "java.lang.Boolean".equals(className)) {
                // for boolean try, try isField method
                this.getterStr = "is" + this.field;
                getter = clas.getMethod(getterStr, new Class[] {});
            } else {
                throw e;
            }
        }
    }

    public void readResultSet(ResultSet rs, String columnName, Object o) throws SQLException {
        if (setter == null) {
            try {
                initSetterMethod(o);
            } catch (Exception e) {
                e.printStackTrace();
                throw new RalasafeException(e);
            }
        }

        try {
            Object readValue = rsReader.reader(rs, columnName);
            setter.invoke(o, new Object[] { readValue });
        } catch (Exception e) {
            e.printStackTrace();
            throw new RalasafeException(e);
        }
    }

    public void readResultSet(ResultSet rs, int columnIndex, Object o) throws SQLException {
        if (setter == null) {
            try {
                initSetterMethod(o);
            } catch (Exception e) {
                log.error("", e);
                throw new RalasafeException(e);
            }
        }

        try {
            Object readValue = rsReader.reader(rs, columnIndex);
            setter.invoke(o, new Object[] { readValue });
        } catch (Exception e) {
            log.error("", e);
            throw new RalasafeException(e);
        }
    }

    public void setPreparedStatement(PreparedStatement pstmt, int paramIndex, Object o) throws SQLException {
        try {
            Object setValue = null;
            if (o instanceof MapStorgeObject) {
                MapStorgeObject mso = (MapStorgeObject) o;
                setValue = mso.get(this.origField);
            } else {
                if (getter == null) {
                    initGetterMethod(o);
                }

                setValue = getter.invoke(o, new Object[] {});
            }

            pstmtSetter.set(pstmt, paramIndex, setValue);
        } catch (Exception e) {
            log.error("", e);
            throw new RalasafeException(e);
        }
    }

    public Object extractFieldValue(Object o) {
        try {
            if (getter == null) {
                initGetterMethod(o);
            }

            return getter.invoke(o, new Object[] {});
        } catch (Exception e) {
            log.error("", e);
            return null;
        }
    }
}