Java JOptionPane.showMessageDialog无效的注释名
通过一些java初级课程,我们了解了这个问题:Java JOptionPane.showMessageDialog无效的注释名,java,Java,通过一些java初级课程,我们了解了这个问题: Multiple markers at this line - Syntax error on token "showMessageDialog", invalid AnnotationName - Syntax error on token "(", { expected after this token - Syntax error on tokens, ConstructorHeaderName expec
Multiple markers at this line
- Syntax error on token "showMessageDialog", invalid
AnnotationName
- Syntax error on token "(", { expected after this token
- Syntax error on tokens, ConstructorHeaderName expected instead
线路是:
JOptionPane.showMessageDialog(null, "The answer is " +sum, "The Title", JOptionPane.INFORMATION_MESSAGE);
Java文档说这个方法接受4个参数,所以我发送4个参数。我还导入了所需的库:
import javax.swing.JOptionPane;
JOptionPane.showInputDialog
工作正常,但不能JOptionPane.showMessageDialog
。我错过了什么?
多谢各位
完整代码
package java_practice;
import javax.swing.JOptionPane;
public class GraphicalUserInterface {
String first_number = JOptionPane.showInputDialog("Enter first number");
String second_number = JOptionPane.showInputDialog("Enter second number");
int num1 = Integer.parseInt(first_number);
int num2 = Integer.parseInt(second_number);
int sum = num1 + num2;
JOptionPane.showMessageDialog(null, "The answer is " +sum, "The Title", JOptionPane.INFORMATION_MESSAGE);
}
您错过了方法声明。您的代码位于类的主体内,这会使编译器/IDE感到困惑,例如关于无效注释的错误等 需要位于某种形式、块或静态块的方法内部
public class GraphicalUserInterface {
public static void main(String [] args) { // <=========
String first_number = JOptionPane.showInputDialog("Enter first number");
String second_number = JOptionPane.showInputDialog("Enter second number");
int num1 = Integer.parseInt(first_number);
int num2 = Integer.parseInt(second_number);
int sum = num1 + num2;
JOptionPane.showMessageDialog(null, "The answer is " +sum, "The Title", JOptionPane.INFORMATION_MESSAGE);
} // <=========
}
公共类GraphicalUserInterface{
公共静态void main(字符串[]args){//报告错误的那一行之前是哪一行…?@Adam我会把代码放进去..1分钟。那是你的代码吗。在method@FastSnail谢谢你…noob错误,下次要多加注意。错过了主块..天哪…noob..谢谢你+1,我会在5分钟内接受它。;)别担心,我们都去过:)