java跟踪执行的sql语句示例分享

代码：

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();  
            }    
    }
}

论坛上看到用下列语句：

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();

才能打印出sql语句。