java - "A JNI error has occurred, please check your installation and try again"运行java程序

Question

这个问题已经有答案了:

List of Java class file format major version numbers? (7 个回答)

已关闭 4 年前。

我正在学习 Java 并在 Thread 上尝试一些代码。我使用 Thread 类编写了一个程序，它编译得很好，但是当我运行该程序时，它给出了错误。完整的错误是:

Error: A JNI error has occurred, please check your installation and
try again

Exception in thread "main"
java.lang.UnsupportedClassVersionError: Main has been compiled by a
more recent version of the Java Runtime (class file version 53.0),
this version of the Java Runtime only recognizes class file versions
up to 52.0

        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$100(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

我的线程java文件是:

  import java.lang.Thread;

    class MyThread extends Thread
    {
        private String s;

        public MyThread(String s)
        {
            this.s = s;
        }

        public void run()
        {
            System.out.println(s);
        }
    }

我的java文件的主要功能是: 导入java.util.Scanner;

class Main
{
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String s1, s2;
        System.out.print("Enter string for first thread: ");
        s1 = scanner.nextLine();
        System.out.print("Enter string for second thread: ");
        s2 = scanner.nextLine();
        MyThread t1 = new MyThread(s1);
        MyThread t2 = new MyThread(s2);
        t1.start();
        t2.start();
        scanner.close();
    }
}

我的操作系统是 Windows 10 家庭版。我使用 javac Main.java 编译了该文件并尝试使用 java Main 运行已编译的 .class 文件。错误的原因是什么？我该如何预防？

Answer 1

java.lang.UnsupportedClassVersionError: Main has been compiled by a
more recent version of the Java Runtime (class file version 53.0),
this version of the Java Runtime only recognizes class file versions
up to 52.0"

您使用 Java 9 编译了代码，但尝试在 Java 8 JVM 上运行它。