图片:
命令提示符显示版本
图片错误
import java.applet.Applet;
import java.awt.*;
public class Hello extends Applet {
// Java applet to draw "Hello World"
public void paint (Graphics page) {
page.drawString ("Hello World!", 50, 50);
}
}
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<HTML>
<HEAD>
<TITLE>HelloWorld Applet</TITLE>
</HEAD>
<BODY>
<APPLET CODE="Hello.class" WIDTH=300 HEIGHT=150>
</APPLET>
</BODY>
</HTML>
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Hello : Unsupported major.minor version 52.0
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问题可能是什么?
我在尝试编译Java程序时遇到错误.
我在Windows上(这是一个特定于Windows的问题),我安装了最新的JDK.
我尝试过涉及PATH变量的解决方案,但错误仍然存在.
控制台输出:
C:\>set path=C:Program Files (x86)\Java\jdk1.7.0\bin
C:\>javac Hello.java
'javac' is not recognized as an internal or external command,
operable program or batch file.
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不支持的主要.minor版本51.0
我正在尝试构建一个应用程序,但它给出了一些错误.我的JDK版本如下:
java version "1.6.0_30"
Java(TM) SE Runtime Environment (build 1.6.0_30-b12)
Java HotSpot(TM) Client VM (build 20.5-b03, mixed mode, sharing)
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这是我的错误日志:
Buildfile: build.xml
compile:
[echo] Compiling the service....
[echo] ...mkdir for classes first....
[echo] ...java classes next....
[echo] ...mkdir for generated code next....
[echo] ...generate stubs/skeletons next....
[wscompile] command line: wscompile -d /home/vivekray/program/MTrans/WEB-INF/classes -features:wsi,documentliteral -gen:server -keep -model /home/vivekray/program/MTrans/WEB-INF/model.gz -verbose -Xprintstacktrace /home/vivekray/program/MTrans/src/config.xml -classpath /home/vivekray/program/MTrans/WEB-INF:/home/vivekray/program/MTrans/WEB-INF/classes:/home/vivekray/program/MTrans/lib/log4j-1.2.16.jar:/home/vivekray/jwsdp-2.0/jwsdp-shared/lib/mail.jar:/home/vivekray/jwsdp-2.0/jwsdp-shared/lib/activation.jar:/home/vivekray/jwsdp-2.0/jaxp/lib/jaxp-api.jar:/home/vivekray/jwsdp-2.0/jaxp/lib/endorsed/dom.jar:/home/vivekray/jwsdp-2.0/jaxp/lib/endorsed/sax.jar:/home/vivekray/jwsdp-2.0/jaxp/lib/endorsed/xalan.jar:/home/vivekray/jwsdp-2.0/jaxp/lib/endorsed/xercesImpl.jar:/home/vivekray/jwsdp-2.0/jaxrpc/lib/jaxrpc-api.jar:/home/vivekray/jwsdp-2.0/jaxrpc/lib/jaxrpc-spi.jar:/home/vivekray/jwsdp-2.0/jaxrpc/lib/jaxrpc-impl.jar:/home/vivekray/jwsdp-2.0/saaj/lib/saaj-api.jar:/home/vivekray/jwsdp-2.0/saaj/lib/saaj-impl.jar:/home/vivekray/jwsdp-2.0/jwsdp-shared/lib/relaxngDatatype.jar:/home/vivekray/jwsdp-2.0/jwsdp-shared/lib/xsdlib.jar:/home/vivekray/jwsdp-2.0/jwsdp-shared/lib/jax-qname.jar:/home/vivekray/jwsdp-2.0/apache-ant/lib/ant.jar:/home/vivekray/jwsdp-2.0/fastinfoset/lib/FastInfoset.jar:/home/vivekray/Softwares/apache-tomcat-7.0.27/lib/servlet-api.jar
[wscompile] [creating model: mtransservice]
[wscompile] [creating service: Mtransservice]
BUILD FAILED
java.lang.UnsupportedClassVersionError: in/cdac/mobile/computing/mtrans/MtransService : Unsupported major.minor version …Run Code Online (Sandbox Code Playgroud) 可能重复:
不支持的主要.minor版本51.0
我安装了JDK7,一个简单的hello word程序得到编译,但是当我运行它时,我得到了以下异常.
Exception in thread "main" java.lang.UnsupportedClassVersionError: a (Unsupported major.minor version 51.0)
at java.lang.ClassLoader.defineClass0(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$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
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我检查java -version了命令提示符,它显示了Java版本1.4.2_03但是当我尝试从java.com安装新的java版本时它说我推荐了Java 7版本.
我无法在HTML中将我的Java应用程序作为Web applet启动(我使用的是HTML 4.01,我知道它在html5中不起作用).它返回的错误消息是:
java:不支持的major.minor版本52.0
我已经尝试降级我的Java JRE/JDK/SDK,但我仍然得到相同的错误消息.我现在使用的当前版本的java是1.8.0_05.
我在使用 IntelliJ 时遇到了这个问题。但是我的系统上新安装的所有东西都是最新版本。
...已由更新版本的 Java Runtime(类文件版本 57.0)编译,此版本的 Java Runtime 仅识别最高 52.0 的类文件版本
我已经设置:
PATH 为 C:\Program Files\Java\jdk-13 JAVA_HOME 为:C:\Program Files\Java\jdk-13 JRE_HOME 为:C:\Program Files\Java\jre1.8.0_221
我已经设置了路径,试图在项目结构中找到变化
完整的错误信息:
H:\087-JAVA\HelloWorld\src>java com.codewithmosh.Main
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.UnsupportedClassVersionError: com/codewithmosh/Main has been compiled by a more recent version of the Java Runtime (class file version 57.0), this version of the Java Runtime only recognizes class file versions up to 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at …Run Code Online (Sandbox Code Playgroud) 我的scala应用程序只能运行Java 7,因为它依赖于只出现在该版本的JDK中的库.
如何在sbt中强制执行该操作,以便在启动sbt运行/编译应用程序时使用错误版本的Java时,会立即向用户显示正确的错误消息?
注意:此处无编译Java™源代码.我只有 Scala源代码.Scala代码需要import java.nio.file.PathJava 7提供的代码.
当我运行java程序时收到此错误..你能否建议我们为什么会收到此错误:
Exception in thread "main" java.lang.UnsupportedClassVersionError:
GenerateInvoice (Unsupported major.minor version 49.0)
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:539)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:123)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:251)
at java.net.URLClassLoader.access$100(URLClassLoader.java:55)
at java.net.URLClassLoader$1.run(URLClassLoader.java:194)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:187)
at java.lang.ClassLoader.loadClass(ClassLoader.java:289)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:274)
at java.lang.ClassLoader.loadClass(ClassLoader.java:235)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:302)
Run Code Online (Sandbox Code Playgroud) 安装Android 5.0后,Eclipse中出现以下错误(SDK 21)
"为Android 5.0加载数据"遇到了问题.
解析android-21的数据失败了
不支持的major.minor版本51.0
我在Ant中运行这个目标.
<target name="compile" depends="init"
description="compile the source " >
<!-- Compile the java code from ${src} into ${build} -->
<javac srcdir="${src}" destdir="${build}"/>
</target>
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它给了我这个错误.
C:\Users\..\workspace\..\build.xml:21: java.lang.UnsupportedClassVersionError:
com/sun/tools/javac/Main : Unsupported major.minor version 51.0
以下是版本:
Apache Ant(TM) version 1.8.2
JDK version is JDK 1.7.0
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这是我在Eclipse中的编译器设置.

请帮我解决一下.