Android——Tomcat+MySQL+Servlet，实现将Client传到的数据写入MySQL_mysql

Android客户端将用户的注册信息上传到Tomcat Web服务器，Servlet将注册信息写入到MySQL中。

1,准备工作

(1)在MySQL中创建好要使用的数据库和数据表。

(2)设置好Tomcat的数据库连接池。

参见Tomcat数据库连接池配置

2，Android客户端Activity和Layout的设计

(1)一个简单的注册界面，sign_layout.xml

sign_layout.xml

<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:focusableInTouchMode="true" android:background="#ff6699cc"     android:orientation="vertical"     android:paddingBottom="@dimen/activity_vertical_margin"     android:paddingLeft="@dimen/activity_horizontal_margin"     android:paddingRight="@dimen/activity_horizontal_margin"     android:paddingTop="@dimen/activity_vertical_margin"     tools:context=".MainActivity" >          <RelativeLayout         android:layout_width="fill_parent"         android:layout_height="fill_parent"         android:background="#fffffffb"         android:orientation="horizontal"         android:padding="40dp" >          <EditText             android:id="@+id/etSgAccount"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:layout_marginTop="30dp"             android:layout_marginBottom="20dp"             android:hint="@string/Account"             android:inputType="textEmailAddress" />          <EditText             android:id="@+id/etSgPassword"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:layout_below="@+id/etSgAccount"             android:layout_marginBottom="20dp"             android:hint="@string/Password"             android:inputType="textPassword" />          <EditText             android:id="@+id/etSgRePassword"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:layout_below="@+id/etSgPassword"             android:layout_marginBottom="20dp"             android:hint="@string/repassword"             android:inputType="textPassword" />           <Button             android:id="@+id/btnSign"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:layout_below="@+id/etSgRePassword"             android:background="#ff6699cc"             android:onClick="onLogin"             android:text="@string/signup"             android:textColor="#ffffffff"             android:textSize="24sp" />     </RelativeLayout>  </LinearLayout>

(2)编写对应的Activity——SignActivity.java

package com.bnutalk.activitytest;  import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.EditText;  public class SignActivity extends Activity {     private EditText username;     private EditText password;     private Button signup;     @Override     protected void onCreate(Bundle savedInstanceState)     {         super.onCreate(savedInstanceState);         setContentView(R.layout.sign_layout);         username=(EditText) findViewById(R.id.etSgAccount);         password=(EditText) findViewById(R.id.etSgPassword);         signup=(Button) findViewById(R.id.btnSign);     }     /*发起HTTP请求*/     public void onLogin(View v)     {         String url="http://172.22.140.237:8080/web/MysServlet";         new HttpThread(url, username.getText().toString(), password.getText().toString()).start();     }  } 

其中的重要代码是函数onLogin,它表示当按下Signup按钮时，启动Http线程，向服务器发起Http请求。

/*发起HTTP请求*/     public void onLogin(View v)     {     /*url要访问的Tomcat的Servlet地址,将ip换成Tomacat所在主机的ip*/         String url="http://172.22.140.237:8080/web/MysServlet";      /*调用访问网络的HttpThread*/         new HttpThread(url, username.getText().toString(), password.getText().toString()).start();     } 

(3)新建一个Tread类——HttpTread

访问网络属于耗时操作，因此用一个单独的线程来实现。

package com.bnutalk.activitytest;  import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL;  import android.R.string;  public class HttpThread extends Thread {     String url;     String username;     String password;      public HttpThread(String url, String username, String password) {         // TODO Auto-generated constructor stub         this.url = url;         this.username = username;         this.password = password;     }      private void doGet() throws IOException {         /*将username和password传给Tomcat服务器*/         url=url+"?username="+username+"&password="+password;         try {             URL httpUrl = new URL(url);             /*获取网络连接*/             HttpURLConnection conn = (HttpURLConnection) httpUrl.openConnection();             /*设置请求方法为GET方法*/             conn.setRequestMethod("GET");             /*设置访问超时时间*/             conn.setReadTimeout(5000);             BufferedReader reader=new BufferedReader(new InputStreamReader(conn.getInputStream()));             String str;             StringBuffer sb=new StringBuffer();             //读取服务器返回的信息             while((str=reader.readLine())!=null)             {                 sb.append(str);             }             //把服务端返回的数据打印出来             System.out.println("result"+sb.toString());         } catch (MalformedURLException e) {             // TODO Auto-generated catch block             e.printStackTrace();         }      }      /*在run中调用doGet*/     @Override     public void run() {         try {             doGet();         } catch (IOException e) {             // TODO Auto-generated catch block             e.printStackTrace();         }     } } 

(4)在AndroidManifest.xml中添加网络访问权限

<uses-permission  android:name="android.permission.INTERNET"/>

如图：

3,Server和Servlet设置

(1)建立好一个server和一个web项目，在web下建立所需的Servlet

如图所示，注册用到的Servlet是MyServlet.java,请忽略LogServlet.java

(2)在web.xml中注册Servlet

<servlet>         <servlet-name>DataServiceServlet</servlet-name>         <servlet-class>com.imooc.servlet.MyServlet</servlet-class> </servlet>     <servlet-mapping>         <servlet-name>DataServiceServlet</servlet-name>         <url-pattern>/DataServiceServlet</url-pattern> </servlet-mapping>

如图所示：

(3)编写MyServlet.java

package com.imooc.servlet;  import java.io.IOException; import java.io.PrintWriter;  import java.sql.*;  import javax.naming.InitialContext; import javax.naming.NamingException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.sql.DataSource;  import org.apache.catalina.Context;  import com.mysql.jdbc.Connection; import com.mysql.jdbc.ResultSet; import com.mysql.jdbc.Statement;  /**  * Servlet implementation class MyServlet  */ @WebServlet("/MyServlet") public class MyServlet extends HttpServlet {     private static final long serialVersionUID = 1L;      /**      * @see HttpServlet#HttpServlet()      */     public MyServlet() {         super();         // TODO Auto-generated constructor stub     }      /**      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse      *      response)      */     protected void doGet(HttpServletRequest request, HttpServletResponse response)             throws ServletException, IOException {         this.doPost(request, response);     }      /**      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse      *      response)      */     protected void doPost(HttpServletRequest request, HttpServletResponse response)             throws ServletException, IOException {             /*获取请求的数据，并向控制台输出*/         String username = request.getParameter("username");         String password = request.getParameter("password");         PrintWriter out = response.getWriter();         System.out.println("username" + "," + username);         System.out.println("password" + "," + password);          int rs ;         String sql = "insert into bnutalk(id,username,psswd) values(3,?,?)";          /*实现向MySQL中插入username和password*/         try {             InitialContext ctx = new InitialContext();             DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/t1");             /*获得数据库的连接*/             java.sql.Connection conn =ds.getConnection();             conn = ds.getConnection();             /*执行sql*/             PreparedStatement ps = conn.prepareStatement(sql);             ps.setString(1, username);             ps.setString(2, password);             rs= ps.executeUpdate();         } catch (SQLException se) {             System.out.println("SQLException: " + se.getMessage());         } catch (NamingException ne) {             System.out.println("NamingException: " + ne.getMessage());         }     } } 

4，运行

(1)运行web项目，run on server

(2)运行Android客户端

如图：

先看看此时数据表中的内容：

(3)注册一个用户

用户名和密码都是csdn

控制台输出：

再次查看数据表：

如果有看不懂的，可以先去补一补Servlet,Tomcat数据库连接池，MySQL，Thread这些基础知识，有个大概印象，最起码能知道其中的逻辑，大体框架，实现机制。脑海中一个框架图，再来看代码就很简单了。