Module org.apache.lucene.core
Package org.apache.lucene.util

Class Constants

java.lang.Object
org.apache.lucene.util.Constants
public final class Constants extends Object
Some useful constants.

  • Field Details

    • UNKNOWN

      private static final String UNKNOWN
      See Also:

    • JVM_VENDOR

      public static final String JVM_VENDOR
      JVM vendor info.

    • JVM_NAME

      public static final String JVM_NAME
      JVM vendor name.

    • JVM_VERSION

      @Deprecated public static final String JVM_VERSION
      Deprecated.
      To detect Java versions use Runtime.version()
      Get the full version string of the current runtime.

    • JVM_SPEC_VERSION

      @Deprecated public static final String JVM_SPEC_VERSION
      Deprecated.
      To detect Java versions use Runtime.version()
      Gets the specification version of the current runtime. This is the feature version converted to String.
      See Also:

    • JAVA_VERSION

      @Deprecated public static final String JAVA_VERSION
      Deprecated.
      To detect Java versions use Runtime.version()
      The value of System.getProperty("java.version").

    • OS_NAME

      public static final String OS_NAME
      The value of System.getProperty("os.name"). *

    • LINUX

      public static final boolean LINUX
      True iff running on Linux.

    • WINDOWS

      public static final boolean WINDOWS
      True iff running on Windows.

    • SUN_OS

      public static final boolean SUN_OS
      True iff running on SunOS.

    • MAC_OS_X

      public static final boolean MAC_OS_X
      True iff running on Mac OS X

    • FREE_BSD

      public static final boolean FREE_BSD
      True iff running on FreeBSD

    • OS_ARCH

      public static final String OS_ARCH
      The value of System.getProperty("os.arch").

    • OS_VERSION

      public static final String OS_VERSION
      The value of System.getProperty("os.version").

    • JAVA_VENDOR

      public static final String JAVA_VENDOR
      The value of System.getProperty("java.vendor").

    • IS_CLIENT_VM

      public static final boolean IS_CLIENT_VM
      True iff the Java runtime is a client runtime and C2 compiler is not enabled.

    • IS_HOTSPOT_VM

      public static final boolean IS_HOTSPOT_VM
      True iff the Java VM is based on Hotspot and has the Hotspot MX bean readable by Lucene.

    • IS_JVMCI_VM

      public static final boolean IS_JVMCI_VM
      True if jvmci is enabled (e.g. graalvm)

    • JRE_IS_64BIT

      public static final boolean JRE_IS_64BIT
      True iff running on a 64bit JVM

    • HAS_FMA

      private static final boolean HAS_FMA
      true if FMA likely means a cpu instruction and not BigDecimal logic.

    • MAX_VECTOR_SIZE

      private static final int MAX_VECTOR_SIZE
      maximum supported vectorsize.

    • HAS_SSE4A

      private static final boolean HAS_SSE4A
      true for an AMD cpu with SSE4a instructions.

    • HAS_FAST_VECTOR_FMA

      public static final boolean HAS_FAST_VECTOR_FMA
      true iff we know VFMA has faster throughput than separate vmul/vadd.

    • HAS_FAST_SCALAR_FMA

      public static final boolean HAS_FAST_SCALAR_FMA
      true iff we know FMA has faster throughput than separate mul/add.

    • JRE_IS_MINIMUM_JAVA8

      @Deprecated public static final boolean JRE_IS_MINIMUM_JAVA8
      Deprecated.
      This constant is useless and always true. To detect Java versions use Runtime.version()
      Always true.
      See Also:

    • JRE_IS_MINIMUM_JAVA9

      @Deprecated public static final boolean JRE_IS_MINIMUM_JAVA9
      Deprecated.
      This constant is useless and always true. To detect Java versions use Runtime.version()
      Always true.
      See Also:

    • JRE_IS_MINIMUM_JAVA11

      @Deprecated public static final boolean JRE_IS_MINIMUM_JAVA11
      Deprecated.
      This constant is useless and always true. To detect Java versions use Runtime.version()
      Always true.
      See Also:

  • Constructor Details

    • Constants

      private Constants()

  • Method Details

    • is64Bit

      private static boolean is64Bit()

    • hasFastVectorFMA

      private static boolean hasFastVectorFMA()

    • hasFastScalarFMA

      private static boolean hasFastScalarFMA()

    • getSysProp

      private static String getSysProp(String property)

    • getSysProp

      private static String getSysProp(String property, String def)

    • logSecurityWarning

      private static void logSecurityWarning(String property)

    • doPrivileged

      private static <T> T doPrivileged(PrivilegedAction<T> action)