package com.lwj.test.proxy; import java.lang.reflect.InvocationHandler; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Proxy; import java.sql.Connection; import java.sql.SQLException; public class DBManager {     private final static ThreadLocal<Connection> conns = new ThreadLocal<Connection>();     private static boolean show_sql = true;       public final static Connection getConnection() throws SQLException {           Connection conn = (Connection) conns.get();           if(conn ==null || conn.isClosed()){               // 这里使用我定义的一个简单的 ConnectionProvider 替代 dataSource 获取Connection               conn = ConnectionProvider.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 = (Connection) conns.get();           try {               if(conn != null && !conn.isClosed()){                   conn.setAutoCommit(true);                   conn.close();               }           } catch (SQLException e) {           }           conns.set(null);       }       /**       * 用于跟踪执行的SQL语句       */      static class _DebugConnection implements InvocationHandler {           private Connection conn = null;         public _DebugConnection(Connection conn) {               this.conn = conn;         }         public Connection getConnection() {               return (Connection) Proxy.newProxyInstance(conn.getClass().getClassLoader(),new Class[]{Connection.class}, this);         }         public Object invoke(Object proxy, Method m, Object[] args) throws Throwable            {               try                {                   String method = m.getName();                   if("prepareStatement".equals(method) || "createStatement".equals(method))                   {                     System.out.println(method);                     System.out.println(args[0]);                 }                   return m.invoke(conn, args);             } catch (InvocationTargetException e) {                   throw e.getTargetException();               }           }       } } package com.lwj.test.proxy; import java.sql.Connection; import java.sql.DriverManager; public class ConnectionProvider {  public static Connection getConnection()       {   Connection connection = null;        try{              Class.forName("oracle.jdbc.OracleDriver").newInstance();              connection = DriverManager.getConnection("jdbc:oracle:thin:@192.168.1.101:1521:orcl", "scott", "tiger");        }catch(Exception e){          }        return connection;     } } package com.lwj.test.proxy; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class TestMain {  public static void main( String[] args )       {               Connection conn = null;               Statement stmt = null;             PreparedStatement pstmt = null;             try              {                   conn = DBManager.getConnection();                 stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);                   stmt.executeUpdate( "insert into test1(id,name,card,age,address) values(9,'liuwj','1234567890988777',24,'hubeitianmen')" );                   /*pstmt = conn.prepareStatement( "insert into test1(id,name,card,age,address) values(?,?,?,?,?)");                 pstmt.setString(1, "10");                 pstmt.setString(2, "liuwj2");                 pstmt.setString(3, "1234567890988777");                 pstmt.setString(4, "22");                 pstmt.setString(5, "123456");                 pstmt.execute();*/             }catch(SQLException e){               }finally{                    try{                      if( pstmt != null ){                       pstmt.close();                       pstmt = null;                          }                    }catch(SQLException e){                    }                     DBManager.closeConnection();               }         } }

pstmt = conn.prepareStatement( "insert into test1(id,name,card,age,address) values(?,?,?,?,?)"); pstmt.setString(1, "10"); pstmt.setString(2, "liuwj2"); pstmt.setString(3, "1234567890988777"); pstmt.setString(4, "22"); pstmt.setString(5, "123456"); pstmt.execute();