我想编写一个示例Java文件，在其中我想知道运行该类的JVM版本。有办法吗？
System.getProperty("java.version")返回你需要的东西。
如果需要，您还可以使用JMX：
ManagementFactory.getRuntimeMXBean().getVmVersion()
只需打电话，
System.out.println(System.getProperty("java.specification.version"));
System.out.println(System.getProperty("java.runtime.version"));
示例输出：
9
9+176
似乎java.specification.version是最好的工作。
例如。来自我之前的一个网站上的小程序：
java.specification.version 1.6
java.version 1.6.0_23
java.vm.version 19.0-b09
java.runtime.version unknown
unknown的java.runtime.version值仅表示applet不受信任。这是受信任的版本：
java.specification.version 1.6
java.version 1.6.0_23
java.vm.version 19.0-b09
java.runtime.version 1.6.0_23-b05
使用：
System.getProperty("java.version");
其中java.version可以替换为与当前Java版本相关的许多其他系统属性之一。这是一张表：
Property Value (OpenJDK 12) Value (Oracle JRE 8u201) Value (Sun JRE 5u22) Description
------------------------------- ----------------------------------------- --------------------------------------- ---------------------------------------------------- ---------------------------------------------------------------------------------------------------------------
java.version "12" "1.8.0_201" "1.5.0_22" Java Runtime Environment version, which may be interpreted as a Runtime.Version
java.version.date "2019-03-19" null null Java Runtime Environment version date, in ISO-8601 YYYY-MM-DD format, which may be interpreted as a LocalDate
java.vendor "Oracle Corporation" "Oracle Corporation" "Sun Microsystems Inc." Java Runtime Environment vendor
java.vendor.version null null null Java vendor version
java.vendor.url "https://java.oracle.com/" "http://java.oracle.com/" "http://java.sun.com/" Java vendor URL
java.vendor.url.bug "https://bugreport.java.com/bugreport/" "http://bugreport.sun.com/bugreport/" "http://java.sun.com/cgi-bin/bugreport.cgi" Undocumented
java.specification.name "Java Platform API Specification" "Java Platform API Specification" "Java Platform API Specification" Java Runtime Environment specification name
java.specification.vendor "Oracle Corporation" "Oracle Corporation" "Sun Microsystems Inc." Java Runtime Environment specification vendor
java.specification.version "12" "1.8" "1.5" Java Runtime Environment specification version, whose value is the feature element of the runtime version
java.vm.name "OpenJDK 64-Bit Server VM" "Java HotSpot(TM) 64-Bit Server VM" "Java HotSpot(TM) 64-Bit Server VM" Java Virtual Machine implementation name
java.vm.vendor "Oracle Corporation" "Oracle Corporation" "Sun Microsystems Inc." Java Virtual Machine implementation vendor
java.vm.version "12+33" "25.201-b09" "1.5.0_22-b03" Java Virtual Machine implementation version which may be interpreted as a Runtime.Version
java.vm.info "mixed mode, sharing" "mixed mode" "mixed mode" Undocumented
java.vm.specification.name "Java Virtual Machine Specification" "Java Virtual Machine Specification" "Java Virtual Machine Specification" Java Virtual Machine specification name
java.vm.specification.vendor "Oracle Corporation" "Oracle Corporation" "Sun Microsystems Inc." Java Virtual Machine specification vendor
java.vm.specification.version "12" "1.8" "1.0" Java Virtual Machine specification version, whose value is the feature element of the runtime version
java.runtime.name "OpenJDK Runtime Environment" "Java(TM) SE Runtime Environment" "Java(TM) 2 Runtime Environment, Standard Edition" Undocumented
java.runtime.version "12+33" "1.8.0_201-b09" "1.5.0_22-b03" Undocumented
java.class.version "56.0" "52.0" "49.0" Java class format version number
jdk.debug "release" null null Undocumented
sun.java.launcher "SUN_STANDARD" "SUN_STANDARD" "SUN_STANDARD" Undocumented
sun.management.compiler "HotSpot 64-Bit Tiered Compilers" "HotSpot 64-Bit Tiered Compilers" "HotSpot 64-Bit Server Compiler" Undocumented
资料来源：
java -XshowSettings:all -version。System.getProperties()的Java API参考文档只是一个调用System.getProperty("java.version")的情况。
使用java.version，java.specification.version和java.runtime.version的例子：Getting version of java in runtime。
下面的java代码返回当前IDE中可用的JVM版本
List<VirtualMachineDescriptor> descriptors = VirtualMachine.list();
for (VirtualMachineDescriptor descriptor : descriptors) {
System.out.println("Found JVM: " + descriptor.displayName());
try {
VirtualMachine vm = VirtualMachine.attach(descriptor);
String version = vm.getSystemProperties().getProperty("java.runtime.version");
System.out.println(" Runtime Version: " + version);
String connectorAddress = vm.getAgentProperties().getProperty("com.sun.management.jmxremote.localConnectorAddress");
if (connectorAddress == null) {
connectorAddress = vm.getAgentProperties().getProperty("com.sun.management.jmxremote.localConnectorAddress");
}
JMXServiceURL url = new JMXServiceURL(connectorAddress);
JMXConnector connector = JMXConnectorFactory.connect(url);
MBeanServerConnection mbs = connector.getMBeanServerConnection();
ObjectName threadName = new ObjectName(ManagementFactory.THREAD_MXBEAN_NAME);
Integer threadCount = (Integer)mbs.getAttribute(threadName, "ThreadCount");
System.out.println(" Thread count: " + threadCount);
}
catch (Exception e) {
// ...
}
输出：
Found JVM: /home/.../STS IDE/sts-bundle/sts-3.7.2.RELEASE//plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -os linux -ws gtk -arch x86_64 -showsplash -launcher /home/.../STS IDE/sts-bundle/sts-3.7.2.RELEASE/STS -name STS --launcher.library /home/.../STS IDE/sts-bundle/sts-3.7.2.RELEASE//plugins/org.eclipse.equinox.launcher.gtk.linux.x86_64_1.1.300.v20150602-1417/eclipse_1612.so -startup /home/.../STS IDE/sts-bundle/sts-3.7.2.RELEASE//plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar --launcher.overrideVmargs -exitdata 1ad000f -product org.springsource.sts.ide -vm /usr/bin/java -vmargs -Dosgi.requiredJavaVersion=1.7 -Xms40m -XX:MaxPermSize=256m -Xverify:none -Xmx1200m -jar /home/.../STS IDE/sts-bundle/sts-3.7.2.RELEASE//plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
Runtime Version: 1.8.0_91-b14
Found JVM: com.intellij.idea.Main
Runtime Version: 1.8.0_91-b14
Found JVM: Test
Runtime Version: 1.7.0_80-b15
根据需要，其他答案可以提供帮助。
就我而言，他们没有。我一直在寻找IBM JDK的“完全限定”版本信息。
因此，“真正的”答案可以是：只需转储所有系统属性，并检查是否有一个可以提供您正在寻找的内容。
就我而言;我发现IBM JDK知道了
属性：java.fullversion
JRE 1.8.0 IBM J9 2.8 Linux amd64-64压缩参考20161013_322271（已启用JIT，已启用AOT）
J9VM - R28_Java8_SR3_20161013_1635_B322271
Jit - Ta.R14.Java.Green_20161011_125790
GC - R28_Java8_SR3_20161013_1635_B322271_CMPRSS J9CL - 20161013_322271
有关版本的信息存储为System类的属性。
http://docs.oracle.com/javase/6/docs/api/java/lang/System.html#getProperties%28%29
System.getProperty（ “sun.arch.data.model”）;
Java 32位和64位控制
Integer vers = Integer.parseInt(System.getProperty("java.version").split("\\.")[1]);
String bitMode = System.getProperty("sun.arch.data.model").toString();
System.out.println(vers);
System.out.println(bitMode);
输出：
6
32