Android 客户端访问服务器以及服务器开发

做Android有一段时间了，除了Android本身的一些组件以及API用的比较多外，开发接触比较多的就是网络这块了，而对于Android来说，我们只需要知道对应的接口就可以进行开发了，但是作为程序员，仅仅知道调用是不够的，所以这两天也对服务器进行简单的了解。

Android 客户端简单代码

别忘了添加网络权限

废话不多说，直接贴代码

xml:

<span style="font-size:14px;"><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="10dp" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"
        android:text="Tips:请一定要在输入框输入内容" />

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/tip"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="请在这里输入内容：" />

        <EditText
            android:id="@+id/input"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
    </LinearLayout>

    <Button
        android:id="@+id/submit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"
        android:text="点击提交" />

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="服务器返回的内容：" />

        <TextView
            android:id="@+id/show"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/hello_world" />
    </LinearLayout>

</LinearLayout></span>

Activity代码：

<span style="font-size:14px;">package com.example.servlet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity {
	// 输入的内容
	private EditText inpuText;
	// 显示servlet返回的内容,也就是你输入的内容
	private TextView showTextView;
	// 提交到服务器按钮
	private Button submitButton;
	// 提交到服务器的参数
	String username;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		inpuText = (EditText) findViewById(R.id.input);
		submitButton = (Button) findViewById(R.id.submit);
		showTextView = (TextView) findViewById(R.id.show);
		submitButton.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {

				// 在子线程进行网络访问操作
				new MyTask().execute();
			}
		});

	}

	class MyTask extends AsyncTask<Void, Void, String> {

		@Override
		protected String doInBackground(Void... params) {

			// 完整的url地址：
			// http://192.168.3.5:8080/HelloWorld/HelloWorld?username=xxxxx
			// 其中xxxxx为你输入的内容
			String urlString = "http://192.168.3.5:8080/HelloWorld/HelloWorld";// 192.168.3.5这个地址是你的电脑的IP地址
			username = inpuText.getText().toString();
			urlString = urlString + "?" + "username=" + username;

			String result = null;
			URL url = null;
			HttpURLConnection connection = null;
			InputStreamReader in = null;
			Log.e("TAG", "TAG1");
			try {
				url = new URL(urlString);
				Log.e("TAG", "TAG1");
				connection = (HttpURLConnection) url.openConnection();
				in = new InputStreamReader(connection.getInputStream());
				BufferedReader bufferedReader = new BufferedReader(in);
				StringBuffer strBuffer = new StringBuffer();
				String line = null;
				while ((line = bufferedReader.readLine()) != null) {
					strBuffer.append(line);
				}
				result = strBuffer.toString();
			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				if (connection != null) {
					connection.disconnect();
				}
				if (in != null) {
					try {
						in.close();
					} catch (IOException e) {
						e.printStackTrace();
					}
				}

			}
			return result;
		}

		@Override
		protected void onPostExecute(String result) {
			showTextView.setText(result);
		}

	}

}</span>

Servlet代码：

<span style="font-size:14px;">package com.hpg.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloWorld extends HttpServlet {

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {

		String usernameString = req.getParameter("username");
		resp.setContentType("text/html");

		PrintWriter out = resp.getWriter();
		// 可以在print中输入任何你想要输入的内容
		out.print("Success! Your username is " + usernameString);
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(req, resp);
	}

}</span>

效果图如下