我是Java初学者,正在尝试使用IntelliJ运行我的代码,我刚刚将它安装为JDK 1.7的IDE。下面这段代码甚至不能编译,并不断给我错误:

Error: Could not find or load main class libTest

Code

import java.lang.Integer;
import java.lang.String;
import java.lang.System;
import java.util.*;

class book {

    private String name = "trial";
    private int bookCode=1;
    private int issued=0;

     public void Issue(){
         if(issued==0) {
             issued=1;
             System.out.println("You have succesfully issued the book");
         }
         else {
             System.out.println("The book is already issued. Please contact the librarian for further details");
         }
    }

    public int checkCode() {
        return bookCode;
    }

    String readName() {
        return name;
    }

    public void setName(String newName){
        name=newName;
    }

    public void setBookCode(int newCode){
        bookCode=newCode;
    }
}

class library {
    private ArrayList books=new ArrayList();

    public void getList(){
        for(int bk:books){
            String bName=books(bk).readName();
            System.out.println((bk+1)+")  "+bName);
        }
    }
}

public class libTest{
    public static void main(String[] args){
        library newLib= new library();
        System.out.println("code working");
   }
}

有任何改变,我必须在编译器设置??或者是代码。


当前回答

In my case the problem seemed to be related to upgrading IntelliJ. When I did this I overwrote the files from the old IntelliJ with the files from the new IntelliJ (2017 community to 2018 community). After that all of my projects were broken. I tried everything in this thread and none of them worked. I tried upgrading gradle to the latest version (4 to 4.8) and that didn't work. The only thing that worked for me was deleting the entire IntelliJ folder and reinstalling it. All of my projects worked after that.

其他回答

当类在默认文件夹中,即类没有声明包时,我就遇到过这样的问题。

所以我猜使用包语句(例如。将org.me.mypackage;)打包到类顶部应该可以修复它。

我从其他地方继承了一堆. java文件,不知道如何让它们在任何IDE中工作。最终,我不得不转到Main.JAVA文件所在的命令行,运行javac Main.JAVA。这创建了一堆. class文件。然后IDE就能够弄清楚要做什么。

对我来说,我尝试了上面的几个选项,没有工作。然后我只是重命名了我的Application类,这可能迫使intelliJ构建一个新的jar和错误消息开始改变。然后我重新命名它,它工作。

modules.xml有错误的内容,我不知道我的IDEA有什么问题。

当我的Java类在src/main/kotlin目录下时,我遇到了这个问题。当我把它移到src/main/java后,问题就不存在了。