HttpClient 4.0

求助HttpClient 4.0
我之前用HttpClient 3.0写了个java程序，我想移植到Android上面去，不过Android的HttpClient是4.0的，于是我决定在java上用HttpClient 4.0重写，下面是我的代码：

public class MyHttpClient {
	public String number;
	public String code="";
	public StringBuffer contentBuffer = new StringBuffer();
	
	// 构造HttpClient的实例
	HttpClient httpClient=new DefaultHttpClient();
	
	HttpGet get;
	HttpPost post;
	
	public void getCode() throws ClientProtocolException, IOException{
		get = new HttpGet("http://10.1.74.16/checkcode.asp");
		//发送请求
		HttpResponse response = httpClient.execute(get);

		InputStream is = response.getEntity().getContent();
		BufferedReader br = new BufferedReader(new InputStreamReader(is));
		
		//保存验证码图片
		String filename="G:\\2.bmp";
		File storeFile = new File(filename);  
		FileOutputStream output=null;
		output = new FileOutputStream(storeFile);
		response.getEntity().writeTo(output);
		output.close();
	}
	
	public void login(String UserId,String PassWord,String CheckCode) throws ClientProtocolException, IOException{
		post=new HttpPost("http://10.1.74.16/login.asp");
		
		List <NameValuePair> nvps = new ArrayList <NameValuePair>();
		//提交两个参数及值
		nvps.add(new BasicNameValuePair("userId", UserId));
		nvps.add(new BasicNameValuePair("pwd", PassWord));
		nvps.add(new BasicNameValuePair("GetCode",CheckCode));
		nvps.add(new BasicNameValuePair("radioUserType","student"));
		
		//网页编码
		UrlEncodedFormEntity params = new UrlEncodedFormEntity(nvps);
		post.setEntity(params);
		
		HttpResponse response=httpClient.execute(post);
		post.abort();
		
		post=new HttpPost("http://10.1.74.16/studentWeb/studentMain.asp");
		response=httpClient.execute(post);
		post.abort();
		HttpEntity entity = response.getEntity(); 
		String body = EntityUtils.toString(entity , "GBK").trim();;  
        System.out.println(body); 	
	}
	
	public void getSource(String textYear) throws ClientProtocolException, IOException{
		post=new HttpPost("http://10.1.74.16/studentWeb/ViewScore/ViewTermScore.asp");
		List <NameValuePair> nvps = new ArrayList <NameValuePair>();
		//提交两个参数及值
		nvps.add(new BasicNameValuePair("textYear","2013"));
		nvps.add(new BasicNameValuePair("SelectTerm","1"));
		
		//网页编码
		UrlEncodedFormEntity params = new UrlEncodedFormEntity(nvps);
		post.setEntity(params);
				
		HttpResponse response=httpClient.execute(post);
		System.out.println(response.getStatusLine());
		post.abort();
		
		System.out.println(EntityUtils.toString(response.getEntity()));
		HttpEntity entity = response.getEntity(); 
		String body = EntityUtils.toString(entity , "GBK").trim();;  
        System.out.println(body); 
		
	}
}

前面的login方法是用来登录的，很顺利，可以返回登录之后的页面，当我执行后面的getScore方法的时候执行System.out.println(response.getStatusLine());这一句返回的是200,OK，是正常的，但是在执行System.out.println(body); 的时候就返回错误

java.net.SocketException: socket closed
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.read(Unknown Source)
	at java.net.SocketInputStream.read(Unknown Source)
	at org.apache.http.impl.io.AbstractSessionInputBuffer.read(AbstractSessionInputBuffer.java:187)
	at org.apache.http.impl.io.ContentLengthInputStream.read(ContentLengthInputStream.java:164)
	at org.apache.http.conn.EofSensorInputStream.read(EofSensorInputStream.java:138)
	at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
	at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
	at sun.nio.cs.StreamDecoder.read(Unknown Source)
	at java.io.InputStreamReader.read(Unknown Source)
	at java.io.Reader.read(Unknown Source)
	at org.apache.http.util.EntityUtils.toString(EntityUtils.java:199)
	at org.apache.http.util.EntityUtils.toString(EntityUtils.java:221)
	at MyHttpClient.getSource(MyHttpClient.java:96)
	at CheckCode$Listen.actionPerformed(CheckCode.java:121)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)