resultsets.java

Connection的代理类

package ConnectionDataBase;

import java.sql.ResultSet;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

/** 
 * 数据库结果集的代理类 
 * @author qibin
 */
public class ResultSets  implements InvocationHandler
{
	 private ResultSet rs = null;
	 private boolean decode = false;
	 
	 public ResultSets(ResultSet rs,boolean decode) 
	 {
		  this.rs = rs;
		  this.decode = decode;
	 }
	 
	 public ResultSet getResultSet()
	 { 
		  Class[] interfaces = rs.getClass().getInterfaces();
		  if(interfaces==null||interfaces.length==0)
		  {
			   interfaces = new Class[1];
			   interfaces[0] = ResultSet.class;  
		  }
	 
		  ResultSet rs2 = (ResultSet)Proxy.newProxyInstance(rs.getClass().getClassLoader(),interfaces,this);
		  return rs2;
	 }

	 /**  
	  * 结果getString方法  
	  */
	 public Object invoke(Object proxy, Method m, Object[] args) throws Throwable 
	 { 
		  String method = m.getName();
		  if(decode && GETSTRING.equals(method))
		  {
			  try
			   {
				    String result = (String)m.invoke(rs,args);
				    
				    if(result!=null)     
				    	return new String(result.getBytes("8859_1"));
				    
				    return null; 
			   }
			   catch(InvocationTargetException e)
			   {
				   throw e.getTargetException();
			   }
		  } 
		  
		 try
		 {
			  return m.invoke(rs, args);
		 }
		 catch(InvocationTargetException e)
		 {
			  throw e.getTargetException();
		 }
	 }
	 
	 private final static String GETSTRING = "getString";

}