public final class JavaEnvUtils
extends java.lang.Object
Starting with Java 10 we've stopped adding JAVA_
 and VERSION_ attributes for new major version numbers
 of the JVM.
| Modifier and Type | Field and Description | 
|---|---|
| static java.lang.String | JAVA_1_0Version constant for Java 1.0 | 
| static java.lang.String | JAVA_1_1Version constant for Java 1.1 | 
| static java.lang.String | JAVA_1_2Version constant for Java 1.2 | 
| static java.lang.String | JAVA_1_3Version constant for Java 1.3 | 
| static java.lang.String | JAVA_1_4Version constant for Java 1.4 | 
| static java.lang.String | JAVA_1_5Version constant for Java 1.5 | 
| static java.lang.String | JAVA_1_6Version constant for Java 1.6 | 
| static java.lang.String | JAVA_1_7Version constant for Java 1.7 | 
| static java.lang.String | JAVA_1_8Version constant for Java 1.8 | 
| static java.lang.String | JAVA_1_9Deprecated. 
 use #JAVA_9 instead | 
| static java.lang.String | JAVA_9Version constant for Java 9 | 
| static int | VERSION_1_0Number Version constant for Java 1.0 | 
| static int | VERSION_1_1Number Version constant for Java 1.1 | 
| static int | VERSION_1_2Number Version constant for Java 1.2 | 
| static int | VERSION_1_3Number Version constant for Java 1.3 | 
| static int | VERSION_1_4Number Version constant for Java 1.4 | 
| static int | VERSION_1_5Number Version constant for Java 1.5 | 
| static int | VERSION_1_6Number Version constant for Java 1.6 | 
| static int | VERSION_1_7Number Version constant for Java 1.7 | 
| static int | VERSION_1_8Number Version constant for Java 1.8 | 
| static int | VERSION_1_9Deprecated. 
 use #VERSION_9 instead | 
| static int | VERSION_9Number Version constant for Java 9 | 
| Modifier and Type | Method and Description | 
|---|---|
| static java.io.File | createVmsJavaOptionFile(java.lang.String[] cmds)Writes the command into a temporary DCL script and returns the
 corresponding File object. | 
| static java.lang.String | getJavaHome()Return the value of ${java.home} | 
| static java.lang.String | getJavaVersion()Returns the version of Java this class is running under. | 
| static int | getJavaVersionNumber()Deprecated. 
 use #getParsedJavaVersion instead | 
| static java.lang.String | getJdkExecutable(java.lang.String command)Finds an executable that is part of a JDK installation based on
 the java.home system property. | 
| static java.lang.String | getJreExecutable(java.lang.String command)Finds an executable that is part of a JRE installation based on
 the java.home system property. | 
| static java.util.Vector<java.lang.String> | getJrePackages()get a vector of strings of packages built into
 that platforms runtime jar(s) | 
| static java.util.Vector<java.lang.String> | getJrePackageTestCases()Testing helper method; kept here for unification of changes. | 
| static DeweyDecimal | getParsedJavaVersion()Returns the version of Java this class is running under. | 
| static boolean | isApacheHarmony()Checks whether the current VM is Apache Harmony. | 
| static boolean | isAtLeastJavaVersion(java.lang.String version)Compares the current Java version to the passed in String -
 assumes the argument is one of the constants defined in this
 class. | 
| static boolean | isClasspathBased()Checks whether the current Java VM is GNU Classpath | 
| static boolean | isGij()Checks whether the current Java VM is the GNU interpreter gij
 or we are running in a gcj precompiled binary. | 
| static boolean | isJavaVersion(java.lang.String version)Compares the current Java version to the passed in String -
 assumes the argument is one of the constants defined in this
 class. | 
| static boolean | isKaffe()Checks whether the current Java VM is Kaffe. | 
public static final java.lang.String JAVA_1_0
public static final int VERSION_1_0
public static final java.lang.String JAVA_1_1
public static final int VERSION_1_1
public static final java.lang.String JAVA_1_2
public static final int VERSION_1_2
public static final java.lang.String JAVA_1_3
public static final int VERSION_1_3
public static final java.lang.String JAVA_1_4
public static final int VERSION_1_4
public static final java.lang.String JAVA_1_5
public static final int VERSION_1_5
public static final java.lang.String JAVA_1_6
public static final int VERSION_1_6
public static final java.lang.String JAVA_1_7
public static final int VERSION_1_7
public static final java.lang.String JAVA_1_8
public static final int VERSION_1_8
@Deprecated public static final java.lang.String JAVA_1_9
@Deprecated public static final int VERSION_1_9
public static final java.lang.String JAVA_9
public static final int VERSION_9
public static java.lang.String getJavaVersion()
Up until Java 8 Java version numbers were 1.VERSION - e.g. 1.8.x for Java 8, starting with Java 9 it became 9.x.
@Deprecated public static int getJavaVersionNumber()
This number can be used for comparisons.
public static DeweyDecimal getParsedJavaVersion()
This number can be used for comparisons.
public static boolean isJavaVersion(java.lang.String version)
JAVA_1_0 through
 JAVA_1_4 need no longer be tested for.version - the version to check against the current version.public static boolean isAtLeastJavaVersion(java.lang.String version)
JAVA_1_0 through
 JAVA_1_4 need no longer be tested for.version - the version to check against the current version.public static boolean isKaffe()
public static boolean isClasspathBased()
public static boolean isGij()
public static boolean isApacheHarmony()
public static java.lang.String getJreExecutable(java.lang.String command)
java, keytool,
 policytool, orbd, rmid,
 rmiregistry, servertool and
 tnameserv are JRE executables on Sun based
 JRE's.
You typically find them in JAVA_HOME/jre/bin if
 JAVA_HOME points to your JDK installation.  JDK
 < 1.2 has them in the same directory as the JDK
 executables.
command - the java executable to find.public static java.lang.String getJdkExecutable(java.lang.String command)
You typically find them in JAVA_HOME/bin if
 JAVA_HOME points to your JDK installation.
command - the java executable to find.public static java.util.Vector<java.lang.String> getJrePackageTestCases()
public static java.util.Vector<java.lang.String> getJrePackages()
public static java.io.File createVmsJavaOptionFile(java.lang.String[] cmds)
                                            throws java.io.IOException
cmds - the command.java.io.IOException - if there is an error writing to the file.public static java.lang.String getJavaHome()