org.apache.hadoop.chukwa.util.DatabaseWriter.java Source code

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Here is the source code for org.apache.hadoop.chukwa.util.DatabaseWriter.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

package org.apache.hadoop.chukwa.util;

import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.text.SimpleDateFormat;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.chukwa.inputtools.mdl.DataConfig;

public class DatabaseWriter {
    private static Log log = LogFactory.getLog(DatabaseWriter.class);
    private Connection conn = null;
    private Statement stmt = null;
    private ResultSet rs = null;

    public DatabaseWriter(String host, String user, String password) {
        DataConfig mdlConfig = new DataConfig();
        String jdbc_url = "jdbc:mysql://" + host + "/";
        if (user != null) {
            jdbc_url = jdbc_url + "?user=" + user;
            if (password != null) {
                jdbc_url = jdbc_url + "&password=" + password;
            }
        }
        try {
            // The newInstance() call is a work around for some
            // broken Java implementations
            Class.forName("com.mysql.jdbc.Driver").newInstance();
        } catch (Exception ex) {
            // handle the error
            log.error(ex, ex);
        }
        try {
            conn = DriverManager.getConnection(jdbc_url);
            log.info("Initialized JDBC URL: " + jdbc_url);
        } catch (SQLException ex) {
            log.error(ex, ex);
        }
    }

    public DatabaseWriter() {
        DataConfig mdlConfig = new DataConfig();
        String jdbc_url = "jdbc:mysql://" + mdlConfig.get("jdbc.host") + "/" + mdlConfig.get("jdbc.db");
        if (mdlConfig.get("jdbc.user") != null) {
            jdbc_url = jdbc_url + "?user=" + mdlConfig.get("jdbc.user");
            if (mdlConfig.get("jdbc.password") != null) {
                jdbc_url = jdbc_url + "&password=" + mdlConfig.get("jdbc.password");
            }
        }
        try {
            // The newInstance() call is a work around for some
            // broken Java implementations
            Class.forName("com.mysql.jdbc.Driver").newInstance();
        } catch (Exception ex) {
            // handle the error
            log.error(ex, ex);
        }
        try {
            conn = DriverManager.getConnection(jdbc_url);
            log.info("Initialized JDBC URL: " + jdbc_url);
        } catch (SQLException ex) {
            log.error(ex, ex);
        }
    }

    public void execute(String query) {
        try {
            stmt = conn.createStatement();
            stmt.execute(query);
        } catch (SQLException ex) {
            // handle any errors
            log.error(ex, ex);
            log.error("SQL Statement:" + query);
            log.error("SQLException: " + ex.getMessage());
            log.error("SQLState: " + ex.getSQLState());
            log.error("VendorError: " + ex.getErrorCode());
        } finally {
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException sqlEx) {
                    // ignore
                }
                stmt = null;
            }
        }
    }

    public ResultSet query(String query) {
        try {
            stmt = conn.createStatement();
            rs = stmt.executeQuery(query);
        } catch (SQLException ex) {
            // handle any errors
            log.error(ex, ex);
            log.error("SQL Statement:" + query);
            log.error("SQLException: " + ex.getMessage());
            log.error("SQLState: " + ex.getSQLState());
            log.error("VendorError: " + ex.getErrorCode());
        } finally {
        }
        return rs;
    }

    public void close() {
        // it is a good idea to release
        // resources in a finally{} block
        // in reverse-order of their creation
        // if they are no-longer needed
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException sqlEx) {
                // ignore
            }
            rs = null;
        }
        if (stmt != null) {
            try {
                stmt.close();
            } catch (SQLException sqlEx) {
                // ignore
            }
            stmt = null;
        }
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException sqlEx) {
                // ignore
            }
            conn = null;
        }
    }

    public String formatTimeStamp(long timestamp) {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String format = formatter.format(timestamp);

        return format;
    }
}