구차니의 잡동사니 모음

$ java --version

openjdk 11.0.1 2018-10-16

OpenJDK Runtime Environment 18.9 (build 11.0.1+13)

OpenJDK 64-Bit Server VM 18.9 (build 11.0.1+13, mixed mode) 

❯ java -version

java version "1.8.0_151"

Java(TM) SE Runtime Environment (build 1.8.0_151-b12)

Java HotSpot(TM) 64-Bit Server VM (build 25.151-b12, mixed mode) 

Note that version must be included in the -version output. Note that this is exactly the command that DefaultJvmVersionDetector parses the output of:

gradle/subprojects/jvm-services/src/main/java/org/gradle/internal/jvm/inspection/DefaultJvmVersionDetector.java

Line 53 in 8e399da

 builder.setCommandLine(javaCommand, "-version");  

    private JavaVersion parseJavaVersionCommandOutput(String javaExecutable, BufferedReader reader) {

        try {

            String versionStr = reader.readLine();

            while (versionStr != null) {

                Matcher matcher = Pattern.compile("(?:java|openjdk) version \"(.+?)\"( \\d{4}-\\d{2}-\\d{2}( LTS)?)?").matcher(versionStr);

                if (matcher.matches()) {

                    return JavaVersion.toVersion(matcher.group(1));

                }

                versionStr = reader.readLine();

            }

        } catch (IOException e) {

            throw new UncheckedIOException(e);

        }

        throw new GradleException(String.format("Could not determine Java version using executable %s.", javaExecutable));

    } 

$ sudo yum install java-11-openjdk.x86_64

$ java -version

openjdk version "11.0.1" 2018-10-16 LTS

OpenJDK Runtime Environment 18.9 (build 11.0.1+13-LTS)

OpenJDK Server VM 18.9 (build 11.0.1+13-LTS, mixed mode, sharing)

$ java --version

openjdk 11.0.1 2018-10-16 LTS

OpenJDK Runtime Environment 18.9 (build 11.0.1+13-LTS)

OpenJDK Server VM 18.9 (build 11.0.1+13-LTS, mixed mode, sharing)

$ sudo yum install java-1.8.0-openjdk.x86_64

$ java -version

openjdk version "1.8.0_191"

OpenJDK Runtime Environment (build 1.8.0_191-b12)

OpenJDK 64-Bit Server VM (build 25.191-b12, mixed mode)