HttpClient的使用模式：

1. 创建一个HttpClent

2.实例化新的HTTP方法，比如PostMethod 或 GetMethod

3.设置HTTP参数名称/值

4.使用HttpClent执行HTTP调用

5.处理Http响应

import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.StatusLine;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;

import com.itheima.httpclient.utils.Utils;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

	Handler handler = new Handler(){
		@Override
		public void handleMessage(android.os.Message msg) {
			Toast.makeText(MainActivity.this, (String)msg.obj, 0).show();
		}
	};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


    //get方法
    public void get(View v){
    	EditText et_name = (EditText) findViewById(R.id.et_name);
    	EditText et_pass = (EditText) findViewById(R.id.et_pass);
    	
    	final String name = et_name.getText().toString();
    	final String pass = et_pass.getText().toString();
    	
    	
    	Thread t = new Thread(){
    		@Override
    		public void run() {
    			String path = "http://192.168.13.13/Web/servlet/CheckLogin?name=" + URLEncoder.encode(name) + "&pass=" + pass;
    	    	//使用httpClient框架做get方式提交
    	    	//1.创建HttpClient对象
    	    	HttpClient hc = new DefaultHttpClient();
    	    	
    	    	//2.创建httpGet对象，构造方法的参数就是网址
    	    	HttpGet hg = new HttpGet(path);
    	    	
    	    	//3.使用客户端对象，把get请求对象发送出去
    	    	try {
    				HttpResponse hr = hc.execute(hg);
    				//拿到响应头中的状态行
    				StatusLine sl = hr.getStatusLine();
    				if(sl.getStatusCode() == 200){
    					//拿到响应头的实体
    					HttpEntity he = hr.getEntity();
    					//拿到实体中的内容，其实就是服务器返回的输入流
    					InputStream is = he.getContent();
    					String text = Utils.getTextFromStream(is);
    					
    					//发送消息，让主线程刷新ui显示text
    					Message msg = handler.obtainMessage();
    					msg.obj = text;
    					handler.sendMessage(msg);
    				}
    			} catch (Exception e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    	};
    	t.start();
    	
    }
    //post方法
    public void post(View v){
    	EditText et_name = (EditText) findViewById(R.id.et_name);
    	EditText et_pass = (EditText) findViewById(R.id.et_pass);
    	
    	final String name = et_name.getText().toString();
    	final String pass = et_pass.getText().toString();
    	
    	Thread t = new Thread(){
    		@Override
    		public void run() {
    			String path = "http://192.168.13.13/Web/servlet/CheckLogin";
    	    	//1.创建客户端对象
    	    	HttpClient hc = new DefaultHttpClient();
    	    	//2.创建post请求对象
    	    	HttpPost hp = new HttpPost(path);
    	    	
    	    	//封装form表单提交的数据
    	    	BasicNameValuePair bnvp = new BasicNameValuePair("name", name);
    	    	BasicNameValuePair bnvp2 = new BasicNameValuePair("pass", pass);
    	    	List<BasicNameValuePair> parameters = new ArrayList<BasicNameValuePair>();
    	    	//把BasicNameValuePair放入集合中
    	    	parameters.add(bnvp);
    	    	parameters.add(bnvp2);
    	    	
    	    	try {
    	    		//要提交的数据都已经在集合中了，把集合传给实体对象
    		    	UrlEncodedFormEntity entity = new UrlEncodedFormEntity(parameters, "utf-8");
    		    	//设置post请求对象的实体，其实就是把要提交的数据封装至post请求的输出流中
    		    	hp.setEntity(entity);
    		    	//3.使用客户端发送post请求
    				HttpResponse hr = hc.execute(hp);
    				if(hr.getStatusLine().getStatusCode() == 200){
    					InputStream is = hr.getEntity().getContent();
    					String text = Utils.getTextFromStream(is);
    					
    					//发送消息，让主线程刷新ui显示text
    					Message msg = handler.obtainMessage();
    					msg.obj = text;
    					handler.sendMessage(msg);
    				}
    			} catch (Exception e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    	};
    	t.start();
    	
    }
}

Utils方法：

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class Utils {

	public static String getTextFromStream(InputStream is){
		
		byte[] b = new byte[1024];
		int len = 0;
		ByteArrayOutputStream bos = new ByteArrayOutputStream();
		try {
			while((len = is.read(b)) != -1){
				bos.write(b, 0, len);
			}
			String text = new String(bos.toByteArray());
			bos.close();
			return text;
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
}