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使用JButton通过JDBC执行SQL查询

[英]Using JButtons to execute SQL queries with JDBC

I'm writing a simple JAVA GUI to read an SQL query from a JTextFrame and execute it. 我正在编写一个简单的JAVA GUI,以从JTextFrame读取SQL查询并执行它。

The connect and execute buttons are both JButtons, but the compiler won't compile my code because I can't append a "throws SQLException" to actionPerformed in my Listener private classes. 连接和执行按钮都是JButton,但是编译器不会编译我的代码,因为我无法在“侦听器”私有类中的actionPerformed后面附加“ throws SQLException”。 I tried writing separate methods, but the same problem still persists. 我尝试编写单独的方法,但是相同的问题仍然存在。 Here's an example: 这是一个例子:

public void connect() throws SQLException {
    conxn = DriverManager.getConnection(URL, Username, Password);
}
private class SelectBut implements ActionListener {  
    public void actionPerformed(ActionEvent event){
        connect();
    }
}

The compiler just throws this back at me: 编译器只是把这个扔给我:

TextFrame.java:123: unreported exception java.sql.SQLException; must be caught or declared to be thrown  
public void actionPerformed(ActionEvent event){connect();}}

Any suggestions? 有什么建议么?

Since SQLException are checked exception , you must re-throw or catch it. 由于SQLException是检查异常,因此必须重新抛出或捕获它。

in your case your actionPerformed method can be something like that : 在您的情况下,您的actionPerformed方法可以是这样的:

public void actionPerformed(ActionEvent event){
    try{
         connect();
    }catch(SQLException e){
         e.printStackTrace();
     }
 }

Here a tutorial about Catching and Handling Exception 这里是有关捕获和处理异常的教程

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