package com.eatle.db;
import java.sql.*;
import java.util.*;
import java.lang.reflect.*;
import javax.sql.DataSource;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.eatle.exception.DBException;
/**
* 数据库管理
*
* @author xt
* @date 2010-2-2 下午10:18:50
*/
public class DBManager {
private final static Log log = LogFactory.getLog(DBManager.class);
private final static ThreadLocal<Connection> conns = new ThreadLocal<Connection>();
private static DataSource dataSource;
private static boolean show_sql = false;
static {
initDataSource(null);
}
/**
* 初始化连接池
*
* @param props
* @param show_sql
* @throws DBException
*/
private final static void initDataSource(Properties dbProperties) {
try {
if (dbProperties == null) {
dbProperties = new Properties();
dbProperties.load(DBManager.class.getResourceAsStream("/db.properties"));
}
Properties cp_props = new Properties();
for (Object key : dbProperties.keySet()) {
String skey = (String) key;
if (skey.startsWith("jdbc.")) {
String name = skey.substring(5);
cp_props.put(name, dbProperties.getProperty(skey));
if ("show_sql".equalsIgnoreCase(name)) {
show_sql = "true".equalsIgnoreCase(dbProperties.getProperty(skey));
}
}
}
dataSource = (DataSource) Class.forName(cp_props.getProperty("datasource")).newInstance();
if (dataSource.getClass().getName().indexOf("c3p0") > 0) {
// Disable JMX in C3P0
System.setProperty("com.mchange.v2.c3p0.management.ManagementCoordinator", "com.mchange.v2.c3p0.management.NullManagementCoordinator");
}
log.info("Using DataSource : " + dataSource.getClass().getName());
BeanUtils.populate(dataSource, cp_props);
Connection conn = getConnection();
DatabaseMetaData mdm = conn.getMetaData();
log.info("Connected to " + mdm.getDatabaseProductName() + " " + mdm.getDatabaseProductVersion());
closeConnection();
} catch (Exception e) {
throw new DBException(e);
}
}
/**
* 断开连接池
*/
public final static void closeDataSource() {
try {
dataSource.getClass().getMethod("close").invoke(dataSource);
} catch (NoSuchMethodException e) {
} catch (Exception e) {
log.error("Unabled to destroy DataSource!!! ", e);
}
}
public final static Connection getConnection() throws SQLException {
Connection conn = conns.get();
if (conn == null || conn.isClosed()) {
conn = dataSource.getConnection();
conns.set(conn);
}
return (show_sql && !Proxy.isProxyClass(conn.getClass())) ? new _DebugConnection(conn).getConnection() : conn;
}
/**
* 关闭连接
*/
public final static void closeConnection() {
Connection conn = conns.get();
try {
if (conn != null && !conn.isClosed()) {
conn.setAutoCommit(true);
conn.close();
}
} catch (SQLException e) {
log.error("Unabled to close connection!!! ", e);
}
conns.set(null);
}
/**
* 用于跟踪执行的SQL语句
*
* @author Winter Lau
*/
static class _DebugConnection implements InvocationHandler {
private final static Log log = LogFactory.getLog(_DebugConnection.class);
private Connection conn = null;
public _DebugConnection(Connection conn) {
this.conn = conn;
}
/**
* Returns the conn.
*
* @return Connection
*/
public Connection getConnection() {
return (Connection) Proxy.newProxyInstance(conn.getClass().getClassLoader(), conn.getClass().getInterfaces(), this);
}
public Object invoke(Object proxy, Method m, Object[] args) throws Throwable {
try {
String method = m.getName();
if ("prepareStatement".equals(method) || "createStatement".equals(method))
log.info("[SQL] >>> " + args[0]);
return m.invoke(conn, args);
} catch (InvocationTargetException e) {
throw e.getTargetException();
}
}
}
public static void main(String[] args) throws SQLException {
DBManager.getConnection();
}
}