【发布时间】：2012-03-09 15:08:41
【问题描述】：
我通过java中的jdbc使用mysql连接成功完成了android中的登录表单......它在我的localhost中成功运行......但是开发站点它不起作用......显示以下错误。
java.sql.SQLException: Unable to connect to any hosts due to exception: java.net.SocketException: java.net.ConnectException: Connection timed out: connect
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: java.net.ConnectException: Connection timed out: connect
STACKTRACE:
java.net.SocketException: java.net.ConnectException: Connection timed out: connect
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:143)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:225)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:1805)
at com.mysql.jdbc.Connection.<init>(Connection.java:452)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.retrieve.retrieve.main(retrieve.java:15)
** END NESTED EXCEPTION **
at com.mysql.jdbc.Connection.createNewIO(Connection.java:1875)
at com.mysql.jdbc.Connection.<init>(Connection.java:452)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.retrieve.retrieve.main(retrieve.java:15)
为什么会出现dis错误。给我一些解决方案。 如果正在运行 localhost 意味着我的 sql 查询是
package com.example.login;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class LoginLayoutActivity extends Activity {
EditText username,password;
TextView error;
Button ok;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
username=(EditText)findViewById(R.id.et_un);
password=(EditText)findViewById(R.id.et_pw);
error=(TextView)findViewById(R.id.tv_error);
ok=(Button)findViewById(R.id.btn_login);
ok.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Editable user = username.getText();
Editable pass = password.getText();
try {
**Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/people", "root", "");
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT password FROM customers where login='"+user+"'");**
if(rs.next())
{
String dbpass = rs.getString(1);
if(dbpass.equals(pass)){
error.setText("Correct Username or Password");
}
else
{
error.setText("Sorry!! Incorrect Username or Password");
}
}
}
catch (SQLException e) {
username.setText(e.toString());
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
}
如果正在运行开发站点意味着我的查询是：
package com.example.login;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class LoginLayoutActivity extends Activity {
EditText username,password;
TextView error;
Button ok;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
username=(EditText)findViewById(R.id.et_un);
password=(EditText)findViewById(R.id.et_pw);
error=(TextView)findViewById(R.id.tv_error);
ok=(Button)findViewById(R.id.btn_login);
ok.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Editable user = username.getText();
Editable pass = password.getText();
try {
**Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://dev.xxxxx.com/xxx", "xxxx", "xxxx");
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT password FROM customers where login='"+user+"'");**
if(rs.next())
{
String dbpass = rs.getString(1);
if(dbpass.equals(pass)){
error.setText("Correct Username or Password");
}
else
{
error.setText("Sorry!! Incorrect Username or Password");
}
}
}
catch (SQLException e) {
username.setText(e.toString());
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
}
dis 开发站点的用户名、密码、数据库名称和 url 都正确而已...那么为什么会出现 dis 错误....给我解决方案...
【问题讨论】：
-
你能ping到那个主机吗？可以通过其他工具连接 MySQL 吗？
-
我 ping 主机...然后只放...没有..这里只使用 jdbc...
-
尝试使用其他工具连接，并尝试缩小问题搜索空间
-
我开发了android原生应用程序...这里只能通过jdbc连接mysql...所以只问...任何其他解决方案
标签： java jdbc exception-handling