systemutils.java

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    /**
     * <p>The <code>java.vm.specification.vendor</code> System Property. Java Virtual
     * Machine specification vendor.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.2
     */
    public static final String JAVA_VM_SPECIFICATION_VENDOR = getSystemProperty("java.vm.specification.vendor");

    /**
     * <p>The <code>java.vm.specification.version</code> System Property. Java Virtual Machine
     * specification version.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.2
     */
    public static final String JAVA_VM_SPECIFICATION_VERSION = getSystemProperty("java.vm.specification.version");

    /**
     * <p>The <code>java.vm.vendor</code> System Property. Java Virtual Machine implementation
     * vendor.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.2
     */
    public static final String JAVA_VM_VENDOR = getSystemProperty("java.vm.vendor");

    /**
     * <p>The <code>java.vm.version</code> System Property. Java Virtual Machine
     * implementation version.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.2
     */
    public static final String JAVA_VM_VERSION = getSystemProperty("java.vm.version");

    /**
     * <p>The <code>line.separator</code> System Property. Line separator
     * (<code>&quot;\n<&quot;</code> on UNIX).</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String LINE_SEPARATOR = getSystemProperty("line.separator");

    /**
     * <p>The <code>os.arch</code> System Property. Operating system architecture.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String OS_ARCH = getSystemProperty("os.arch");

    /**
     * <p>The <code>os.name</code> System Property. Operating system name.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String OS_NAME = getSystemProperty("os.name");

    /**
     * <p>The <code>os.version</code> System Property. Operating system version.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String OS_VERSION = getSystemProperty("os.version");

    /**
     * <p>The <code>path.separator</code> System Property. Path separator
     * (<code>&quot;:&quot;</code> on UNIX).</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String PATH_SEPARATOR = getSystemProperty("path.separator");

    /**
     * <p>The <code>user.country</code> or <code>user.region</code> System Property.
     * User's country code, such as <code>GB</code>. First in JDK version 1.2 as
     * <code>user.region</code>. Renamed to <code>user.country</code> in 1.4</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since 2.0
     * @since Java 1.2
     */
    public static final String USER_COUNTRY = 
        (getSystemProperty("user.country") == null ?
            getSystemProperty("user.region") : getSystemProperty("user.country"));

    /**
     * <p>The <code>user.dir</code> System Property. User's current working
     * directory.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String USER_DIR = getSystemProperty("user.dir");

    /**
     * <p>The <code>user.home</code> System Property. User's home directory.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String USER_HOME = getSystemProperty("user.home");

    /**
     * <p>The <code>user.language</code> System Property. User's language code,
     * such as 'en'.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since 2.0
     * @since Java 1.2
     */
    public static final String USER_LANGUAGE = getSystemProperty("user.language");

    /**
     * <p>The <code>user.name</code> System Property. User's account name.</p>
     *
     * <p>Defaults to <code>null</code> if the runtime does not have
     * security access to read this property or the property does not exist.</p>
     * 
     * @since Java 1.1
     */
    public static final String USER_NAME = getSystemProperty("user.name");

    // Java version
    //-----------------------------------------------------------------------
    // These MUST be declared after those above as they depend on the
    // values being set up
    
    /**
     * <p>Gets the Java version as a <code>float</code>.</p>
     *
     * <p>Example return values:</p>
     * <ul>
     *  <li><code>1.2f</code> for JDK 1.2
     *  <li><code>1.31f</code> for JDK 1.3.1
     * </ul>
     *
     * <p>The field will return zero if {@link #JAVA_VERSION} is <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final float JAVA_VERSION_FLOAT = getJavaVersionAsFloat();

    /**
     * <p>Gets the Java version as an <code>int</code>.</p>
     *
     * <p>Example return values:</p>
     * <ul>
     *  <li><code>120</code> for JDK 1.2
     *  <li><code>131</code> for JDK 1.3.1
     * </ul>
     *
     * <p>The field will return zero if {@link #JAVA_VERSION} is <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final int JAVA_VERSION_INT = getJavaVersionAsInt();

    // Java version checks
    //-----------------------------------------------------------------------
    // These MUST be declared after those above as they depend on the
    // values being set up
    
    /**
     * <p>Is <code>true</code> if this is Java version 1.1 (also 1.1.x versions).</p>
     *
     * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
     * <code>null</code>.</p>
     */
    public static final boolean IS_JAVA_1_1 = getJavaVersionMatches("1.1");

    /**
     * <p>Is <code>true</code> if this is Java version 1.2 (also 1.2.x versions).</p>
     *
     * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
     * <code>null</code>.</p>
     */
    public static final boolean IS_JAVA_1_2 = getJavaVersionMatches("1.2");

    /**
     * <p>Is <code>true</code> if this is Java version 1.3 (also 1.3.x versions).</p>
     *
     * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
     * <code>null</code>.</p>
     */
    public static final boolean IS_JAVA_1_3 = getJavaVersionMatches("1.3");

    /**
     * <p>Is <code>true</code> if this is Java version 1.4 (also 1.4.x versions).</p>
     *
     * <p>The field will <code>false</code> false if {@link #JAVA_VERSION} is
     * <code>null</code>.</p>
     */
    public static final boolean IS_JAVA_1_4 = getJavaVersionMatches("1.4");

    /**
     * <p>Is <code>true</code> if this is Java version 1.5 (also 1.5.x versions).</p>
     *
     * <p>The field will return <code>false</code> if {@link #JAVA_VERSION} is
     * <code>null</code>.</p>
     */
    public static final boolean IS_JAVA_1_5 = getJavaVersionMatches("1.5");

    // Operating system checks
    //-----------------------------------------------------------------------
    // These MUST be declared after those above as they depend on the
    // values being set up
    // OS names from http://www.vamphq.com/os.html
    // Selected ones included - please advise [e-mail]
    // if you want another added or a mistake corrected

    /**
     * <p>Is <code>true</code> if this is AIX.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
     * <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final boolean IS_OS_AIX = getOSMatches("AIX");

    /**
     * <p>Is <code>true</code> if this is HP-UX.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
     * <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final boolean IS_OS_HP_UX = getOSMatches("HP-UX");

    /**
     * <p>Is <code>true</code> if this is Irix.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
     * <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final boolean IS_OS_IRIX = getOSMatches("Irix");

    /**
     * <p>Is <code>true</code> if this is Linux.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
     * <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final boolean IS_OS_LINUX = getOSMatches("Linux") || getOSMatches("LINUX");

    /**
     * <p>Is <code>true</code> if this is Mac.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is
     * <code>null</code>.</p>
     * 
     * @since 2.0
     */
    public static final boolean IS_OS_MAC = getOSMatches("Mac");

    /**
     * <p>Is <code>true</code> if this is Mac.</p>
     *
     * <p>The field will return <code>false</code> if <code>OS_NAME</code> is