Question

我已经阅读了一些关于jdts.jar库的文章然后我想实现它到android app，已经做了一些编码，但我总是无法连接数据库sql server。我第一次尝试远程使用Navicat SQL浏览器，我可以连接它，但当我做android编码时，我无法连接它。已经检查了ip public，username，password和database name，它们与我的android编码相同。这是我的日志猫：

        07-20 16:32:49.270  31447-31447/? E/AndroidRuntime? FATAL EXCEPTION: main
        java.lang.RuntimeException: Unable to start activity ComponentInfo{com.avian.apps.avian/com.avian.apps.avian.LoginActivity}: android.os.NetworkOnMainThreadException
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2186)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2236)
        at android.app.ActivityThread.access$600(ActivityThread.java:145)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1238)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5099)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:803)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:570)
        at dalvik.system.NativeStart.main(Native Method)
        Caused by: android.os.NetworkOnMainThreadException
        at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1118)
        at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
        at libcore.io.IoBridge.connectErrno(IoBridge.java:131)
        at libcore.io.IoBridge.connect(IoBridge.java:116)
        at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
        at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
        at java.net.Socket.connect(Socket.java:847)
        at net.sourceforge.jtds.jdbc.SharedSocket.createSocketForJDBC3(SharedSocket.java:288)
        at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:251)
        at net.sourceforge.jtds.jdbc.JtdsConnection.<init>(JtdsConnection.java:331)
        at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184)
        at java.sql.DriverManager.getConnection(DriverManager.java:175)
        at java.sql.DriverManager.getConnection(DriverManager.java:209)
        at com.avian.apps.avian.ConnectionClass.getConnection(ConnectionClass.java:25)
        at com.avian.apps.avian.LoginActivity.onCreate(LoginActivity.java:36)
        at android.app.Activity.performCreate(Activity.java:5117)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1081)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2150)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2236)
        at android.app.ActivityThread.access$600(ActivityThread.java:145)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1238)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5099)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:803)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:570)
        at dalvik.system.NativeStart.main(Native Method)

和我的ConnectionClass：

        public class ConnectionClass {
        private Connection connect;
        private String driverName = "net.sourceforge.jtds.jdbc.Driver"; 
        private String jdbc = "jdbc:jtds:sqlserver://";
        private String host = "x.x.x.x:"; // x.x.x.x : server ip public
        private String port = "1433/"; // Port Default SQLServer
        private String database = "MOB_APPS"; 
        private String url = jdbc + host + port + database;
        private String username = "sa"; // username default SQLServer
        private String password = "admin.123";
        public Connection getConnection() throws SQLException {
        if (connect == null) {
            try {
            Class.forName(driverName);
            try {
                connect = DriverManager.getConnection(url, username, password);
                Log.d("Success","notifmessage");
            } catch (SQLException se) {
                Log.d("Failed", "notifmessage");
            }
            } catch (ClassNotFoundException cnfe) {
            Log.d("Class not found "+cnfe,"notifmessage");
            }
        }
        return connect;
        }
        }

谁能帮我解决这个问题呢？提前致谢

Answer 1

在建立连接之前调用此方法

        Log.i("Android", " MySQL Connect.");
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
                .permitAll().build();
        StrictMode.setThreadPolicy(policy);

请参阅更新的功能。

 public Connection getConnection() throws SQLException {
        Log.i("Android", " MySQL Connect.");
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
                .permitAll().build();
        StrictMode.setThreadPolicy(policy);
        if (connect == null) {
            try {
                Class.forName(driverName);
                try {
                    connect = DriverManager.getConnection(url, username, password);
                    Log.d("Success", "notifmessage");
                } catch (SQLException se) {
                    Log.d("Failed", "notifmessage");
                }
            } catch (ClassNotFoundException cnfe) {
                Log.d("Class not found " + cnfe, "notifmessage");
            }
        }
        return connect;
    }

<强>更新

我的工作代码注意我使用的旧版本的jar jtds 1.2.7文件存在最新版本的问题。

public class DBconnection {

    public static String User_name = "saxxxx";
    public static String User_pass = "xxxxxh";
    public static String Db_name = "xxxxx";
    static Context mcontext;
    public static Connection Conn = null;
    public static String Server_ip = "192.168.5.14:1433;";

    public static Connection Getconnection() {

        Log.i("Android", " MySQL Connect.");
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
                .permitAll().build();
        StrictMode.setThreadPolicy(policy);
        String connString = null;
        try {
            Log.i("SQL Looking", "Start Looking for server");
            String driver = "net.sourceforge.jtds.jdbc.Driver";
            Class.forName(driver).newInstance();
            connString = "jdbc:jtds:sqlserver://" + Server_ip
                    + ";databaseName=" + Db_name + ";user=" + User_name
                    + ";password=" + User_pass + ";";

            Conn = DriverManager.getConnection(connString);
            Log.i("Connection", "open DB Class");
        } catch (Exception e) {
            Toast.makeText(mcontext, e.toString() + "db", Toast.LENGTH_LONG)
                    .show();
            Log.w("Error connection", e.getMessage());

        }
        return Conn;
    }

    public static void close_DB() {

        try {
            Conn.close();
            Log.i("Connection", "Close DB Class");
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}

使用jdts

1 个答案: