cf 推送失败 java 版本不匹配

Question

我正在尝试将“spring-music”演示应用程序推送到我的本地开发云基金会，但出现以下错误。当我运行命令“cf log spring-music --recent”时，我得到以下输出。

2020-10-21T00:41:39.96+0300 [APP/PROC/WEB/0] OUT JVM Memory Configuration: -Xmx408076K -Xss1M -XX:ReservedCodeCacheSize=240M -XX:MaxDirectMemorySize=10M -XX:MaxMetaspaceSize=128499K
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR Exception in thread "main" java.lang.UnsupportedClassVersionError: org/cloudfoundry/samples/music/Application has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0                                                                                                                                                                                                                   
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.lang.ClassLoader.defineClass1(Native Method)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.lang.ClassLoader.defineClass(ClassLoader.java:756)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.security.AccessController.doPrivileged(Native Method)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:92)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:46)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at org.springframework.boot.loader.Launcher.launch(Launcher.java:51)
   2020-10-21T00:41:40.64+0300 [APP/PROC/WEB/0] ERR     at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:52)

Answer 1

而乔治的回答 is also correct, what you probably want to do is just use Java 11 to run your app.

您可以告诉 Java 构建包您希望安装 Java 11，而不是默认安装的（正如我撰写本文时），即 Java 8。

针对您的应用程序运行cf set-env <app-name> JBP_CONFIG_OPEN_JDK_JRE '{jre: { version: 11.+ }}'或将该环境变量添加到您的manifest.yml 中。然后是cf restage你的应用程序。Java buildpack 将看到它并自动为您安装 Java 11。