| /* |
| * Copyright (c) 1994, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package java.lang; |
| |
| import java.io.*; |
| import java.util.Properties; |
| import java.util.PropertyPermission; |
| import java.util.StringTokenizer; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.security.AllPermission; |
| import java.nio.channels.Channel; |
| import java.nio.channels.spi.SelectorProvider; |
| import sun.nio.ch.Interruptible; |
| import sun.reflect.CallerSensitive; |
| import sun.reflect.Reflection; |
| import sun.security.util.SecurityConstants; |
| import sun.reflect.annotation.AnnotationType; |
| |
| /** |
| * The <code>System</code> class contains several useful class fields |
| * and methods. It cannot be instantiated. |
| * |
| * <p>Among the facilities provided by the <code>System</code> class |
| * are standard input, standard output, and error output streams; |
| * access to externally defined properties and environment |
| * variables; a means of loading files and libraries; and a utility |
| * method for quickly copying a portion of an array. |
| * |
| * @author unascribed |
| * @since JDK1.0 |
| */ |
| public final class System { |
| |
| /* register the natives via the static initializer. |
| * |
| * VM will invoke the initializeSystemClass method to complete |
| * the initialization for this class separated from clinit. |
| * Note that to use properties set by the VM, see the constraints |
| * described in the initializeSystemClass method. |
| */ |
| private static native void registerNatives(); |
| static { |
| registerNatives(); |
| } |
| |
| /** Don't let anyone instantiate this class */ |
| private System() { |
| } |
| |
| /** |
| * The "standard" input stream. This stream is already |
| * open and ready to supply input data. Typically this stream |
| * corresponds to keyboard input or another input source specified by |
| * the host environment or user. |
| */ |
| public final static InputStream in = null; |
| |
| /** |
| * The "standard" output stream. This stream is already |
| * open and ready to accept output data. Typically this stream |
| * corresponds to display output or another output destination |
| * specified by the host environment or user. |
| * <p> |
| * For simple stand-alone Java applications, a typical way to write |
| * a line of output data is: |
| * <blockquote><pre> |
| * System.out.println(data) |
| * </pre></blockquote> |
| * <p> |
| * See the <code>println</code> methods in class <code>PrintStream</code>. |
| * |
| * @see java.io.PrintStream#println() |
| * @see java.io.PrintStream#println(boolean) |
| * @see java.io.PrintStream#println(char) |
| * @see java.io.PrintStream#println(char[]) |
| * @see java.io.PrintStream#println(double) |
| * @see java.io.PrintStream#println(float) |
| * @see java.io.PrintStream#println(int) |
| * @see java.io.PrintStream#println(long) |
| * @see java.io.PrintStream#println(java.lang.Object) |
| * @see java.io.PrintStream#println(java.lang.String) |
| */ |
| public final static PrintStream out = null; |
| |
| /** |
| * The "standard" error output stream. This stream is already |
| * open and ready to accept output data. |
| * <p> |
| * Typically this stream corresponds to display output or another |
| * output destination specified by the host environment or user. By |
| * convention, this output stream is used to display error messages |
| * or other information that should come to the immediate attention |
| * of a user even if the principal output stream, the value of the |
| * variable <code>out</code>, has been redirected to a file or other |
| * destination that is typically not continuously monitored. |
| */ |
| public final static PrintStream err = null; |
| |
| /* The security manager for the system. |
| */ |
| private static volatile SecurityManager security = null; |
| |
| /** |
| * Reassigns the "standard" input stream. |
| * |
| * <p>First, if there is a security manager, its <code>checkPermission</code> |
| * method is called with a <code>RuntimePermission("setIO")</code> permission |
| * to see if it's ok to reassign the "standard" input stream. |
| * <p> |
| * |
| * @param in the new standard input stream. |
| * |
| * @throws SecurityException |
| * if a security manager exists and its |
| * <code>checkPermission</code> method doesn't allow |
| * reassigning of the standard input stream. |
| * |
| * @see SecurityManager#checkPermission |
| * @see java.lang.RuntimePermission |
| * |
| * @since JDK1.1 |
| */ |
| public static void setIn(InputStream in) { |
| checkIO(); |
| setIn0(in); |
| } |
| |
| /** |
| * Reassigns the "standard" output stream. |
| * |
| * <p>First, if there is a security manager, its <code>checkPermission</code> |
| * method is called with a <code>RuntimePermission("setIO")</code> permission |
| * to see if it's ok to reassign the "standard" output stream. |
| * |
| * @param out the new standard output stream |
| * |
| * @throws SecurityException |
| * if a security manager exists and its |
| * <code>checkPermission</code> method doesn't allow |
| * reassigning of the standard output stream. |
| * |
| * @see SecurityManager#checkPermission |
| * @see java.lang.RuntimePermission |
| * |
| * @since JDK1.1 |
| */ |
| public static void setOut(PrintStream out) { |
| checkIO(); |
| setOut0(out); |
| } |
| |
| /** |
| * Reassigns the "standard" error output stream. |
| * |
| * <p>First, if there is a security manager, its <code>checkPermission</code> |
| * method is called with a <code>RuntimePermission("setIO")</code> permission |
| * to see if it's ok to reassign the "standard" error output stream. |
| * |
| * @param err the new standard error output stream. |
| * |
| * @throws SecurityException |
| * if a security manager exists and its |
| * <code>checkPermission</code> method doesn't allow |
| * reassigning of the standard error output stream. |
| * |
| * @see SecurityManager#checkPermission |
| * @see java.lang.RuntimePermission |
| * |
| * @since JDK1.1 |
| */ |
| public static void setErr(PrintStream err) { |
| checkIO(); |
| setErr0(err); |
| } |
| |
| private static volatile Console cons = null; |
| /** |
| * Returns the unique {@link java.io.Console Console} object associated |
| * with the current Java virtual machine, if any. |
| * |
| * @return The system console, if any, otherwise <tt>null</tt>. |
| * |
| * @since 1.6 |
| */ |
| public static Console console() { |
| if (cons == null) { |
| synchronized (System.class) { |
| cons = sun.misc.SharedSecrets.getJavaIOAccess().console(); |
| } |
| } |
| return cons; |
| } |
| |
| /** |
| * Returns the channel inherited from the entity that created this |
| * Java virtual machine. |
| * |
| * <p> This method returns the channel obtained by invoking the |
| * {@link java.nio.channels.spi.SelectorProvider#inheritedChannel |
| * inheritedChannel} method of the system-wide default |
| * {@link java.nio.channels.spi.SelectorProvider} object. </p> |
| * |
| * <p> In addition to the network-oriented channels described in |
| * {@link java.nio.channels.spi.SelectorProvider#inheritedChannel |
| * inheritedChannel}, this method may return other kinds of |
| * channels in the future. |
| * |
| * @return The inherited channel, if any, otherwise <tt>null</tt>. |
| * |
| * @throws IOException |
| * If an I/O error occurs |
| * |
| * @throws SecurityException |
| * If a security manager is present and it does not |
| * permit access to the channel. |
| * |
| * @since 1.5 |
| */ |
| public static Channel inheritedChannel() throws IOException { |
| return SelectorProvider.provider().inheritedChannel(); |
| } |
| |
| private static void checkIO() { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(new RuntimePermission("setIO")); |
| } |
| } |
| |
| private static native void setIn0(InputStream in); |
| private static native void setOut0(PrintStream out); |
| private static native void setErr0(PrintStream err); |
| |
| /** |
| * Sets the System security. |
| * |
| * <p> If there is a security manager already installed, this method first |
| * calls the security manager's <code>checkPermission</code> method |
| * with a <code>RuntimePermission("setSecurityManager")</code> |
| * permission to ensure it's ok to replace the existing |
| * security manager. |
| * This may result in throwing a <code>SecurityException</code>. |
| * |
| * <p> Otherwise, the argument is established as the current |
| * security manager. If the argument is <code>null</code> and no |
| * security manager has been established, then no action is taken and |
| * the method simply returns. |
| * |
| * @param s the security manager. |
| * @exception SecurityException if the security manager has already |
| * been set and its <code>checkPermission</code> method |
| * doesn't allow it to be replaced. |
| * @see #getSecurityManager |
| * @see SecurityManager#checkPermission |
| * @see java.lang.RuntimePermission |
| */ |
| public static |
| void setSecurityManager(final SecurityManager s) { |
| try { |
| s.checkPackageAccess("java.lang"); |
| } catch (Exception e) { |
| // no-op |
| } |
| setSecurityManager0(s); |
| } |
| |
| private static synchronized |
| void setSecurityManager0(final SecurityManager s) { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| // ask the currently installed security manager if we |
| // can replace it. |
| sm.checkPermission(new RuntimePermission |
| ("setSecurityManager")); |
| } |
| |
| if ((s != null) && (s.getClass().getClassLoader() != null)) { |
| // New security manager class is not on bootstrap classpath. |
| // Cause policy to get initialized before we install the new |
| // security manager, in order to prevent infinite loops when |
| // trying to initialize the policy (which usually involves |
| // accessing some security and/or system properties, which in turn |
| // calls the installed security manager's checkPermission method |
| // which will loop infinitely if there is a non-system class |
| // (in this case: the new security manager class) on the stack). |
| AccessController.doPrivileged(new PrivilegedAction<Object>() { |
| public Object run() { |
| s.getClass().getProtectionDomain().implies |
| (SecurityConstants.ALL_PERMISSION); |
| return null; |
| } |
| }); |
| } |
| |
| security = s; |
| } |
| |
| /** |
| * Gets the system security interface. |
| * |
| * @return if a security manager has already been established for the |
| * current application, then that security manager is returned; |
| * otherwise, <code>null</code> is returned. |
| * @see #setSecurityManager |
| */ |
| public static SecurityManager getSecurityManager() { |
| return security; |
| } |
| |
| /** |
| * Returns the current time in milliseconds. Note that |
| * while the unit of time of the return value is a millisecond, |
| * the granularity of the value depends on the underlying |
| * operating system and may be larger. For example, many |
| * operating systems measure time in units of tens of |
| * milliseconds. |
| * |
| * <p> See the description of the class <code>Date</code> for |
| * a discussion of slight discrepancies that may arise between |
| * "computer time" and coordinated universal time (UTC). |
| * |
| * @return the difference, measured in milliseconds, between |
| * the current time and midnight, January 1, 1970 UTC. |
| * @see java.util.Date |
| */ |
| public static native long currentTimeMillis(); |
| |
| /** |
| * Returns the current value of the running Java Virtual Machine's |
| * high-resolution time source, in nanoseconds. |
| * |
| * <p>This method can only be used to measure elapsed time and is |
| * not related to any other notion of system or wall-clock time. |
| * The value returned represents nanoseconds since some fixed but |
| * arbitrary <i>origin</i> time (perhaps in the future, so values |
| * may be negative). The same origin is used by all invocations of |
| * this method in an instance of a Java virtual machine; other |
| * virtual machine instances are likely to use a different origin. |
| * |
| * <p>This method provides nanosecond precision, but not necessarily |
| * nanosecond resolution (that is, how frequently the value changes) |
| * - no guarantees are made except that the resolution is at least as |
| * good as that of {@link #currentTimeMillis()}. |
| * |
| * <p>Differences in successive calls that span greater than |
| * approximately 292 years (2<sup>63</sup> nanoseconds) will not |
| * correctly compute elapsed time due to numerical overflow. |
| * |
| * <p>The values returned by this method become meaningful only when |
| * the difference between two such values, obtained within the same |
| * instance of a Java virtual machine, is computed. |
| * |
| * <p> For example, to measure how long some code takes to execute: |
| * <pre> {@code |
| * long startTime = System.nanoTime(); |
| * // ... the code being measured ... |
| * long estimatedTime = System.nanoTime() - startTime;}</pre> |
| * |
| * <p>To compare two nanoTime values |
| * <pre> {@code |
| * long t0 = System.nanoTime(); |
| * ... |
| * long t1 = System.nanoTime();}</pre> |
| * |
| * one should use {@code t1 - t0 < 0}, not {@code t1 < t0}, |
| * because of the possibility of numerical overflow. |
| * |
| * @return the current value of the running Java Virtual Machine's |
| * high-resolution time source, in nanoseconds |
| * @since 1.5 |
| */ |
| public static native long nanoTime(); |
| |
| /** |
| * Copies an array from the specified source array, beginning at the |
| * specified position, to the specified position of the destination array. |
| * A subsequence of array components are copied from the source |
| * array referenced by <code>src</code> to the destination array |
| * referenced by <code>dest</code>. The number of components copied is |
| * equal to the <code>length</code> argument. The components at |
| * positions <code>srcPos</code> through |
| * <code>srcPos+length-1</code> in the source array are copied into |
| * positions <code>destPos</code> through |
| * <code>destPos+length-1</code>, respectively, of the destination |
| * array. |
| * <p> |
| * If the <code>src</code> and <code>dest</code> arguments refer to the |
| * same array object, then the copying is performed as if the |
| * components at positions <code>srcPos</code> through |
| * <code>srcPos+length-1</code> were first copied to a temporary |
| * array with <code>length</code> components and then the contents of |
| * the temporary array were copied into positions |
| * <code>destPos</code> through <code>destPos+length-1</code> of the |
| * destination array. |
| * <p> |
| * If <code>dest</code> is <code>null</code>, then a |
| * <code>NullPointerException</code> is thrown. |
| * <p> |
| * If <code>src</code> is <code>null</code>, then a |
| * <code>NullPointerException</code> is thrown and the destination |
| * array is not modified. |
| * <p> |
| * Otherwise, if any of the following is true, an |
| * <code>ArrayStoreException</code> is thrown and the destination is |
| * not modified: |
| * <ul> |
| * <li>The <code>src</code> argument refers to an object that is not an |
| * array. |
| * <li>The <code>dest</code> argument refers to an object that is not an |
| * array. |
| * <li>The <code>src</code> argument and <code>dest</code> argument refer |
| * to arrays whose component types are different primitive types. |
| * <li>The <code>src</code> argument refers to an array with a primitive |
| * component type and the <code>dest</code> argument refers to an array |
| * with a reference component type. |
| * <li>The <code>src</code> argument refers to an array with a reference |
| * component type and the <code>dest</code> argument refers to an array |
| * with a primitive component type. |
| * </ul> |
| * <p> |
| * Otherwise, if any of the following is true, an |
| * <code>IndexOutOfBoundsException</code> is |
| * thrown and the destination is not modified: |
| * <ul> |
| * <li>The <code>srcPos</code> argument is negative. |
| * <li>The <code>destPos</code> argument is negative. |
| * <li>The <code>length</code> argument is negative. |
| * <li><code>srcPos+length</code> is greater than |
| * <code>src.length</code>, the length of the source array. |
| * <li><code>destPos+length</code> is greater than |
| * <code>dest.length</code>, the length of the destination array. |
| * </ul> |
| * <p> |
| * Otherwise, if any actual component of the source array from |
| * position <code>srcPos</code> through |
| * <code>srcPos+length-1</code> cannot be converted to the component |
| * type of the destination array by assignment conversion, an |
| * <code>ArrayStoreException</code> is thrown. In this case, let |
| * <b><i>k</i></b> be the smallest nonnegative integer less than |
| * length such that <code>src[srcPos+</code><i>k</i><code>]</code> |
| * cannot be converted to the component type of the destination |
| * array; when the exception is thrown, source array components from |
| * positions <code>srcPos</code> through |
| * <code>srcPos+</code><i>k</i><code>-1</code> |
| * will already have been copied to destination array positions |
| * <code>destPos</code> through |
| * <code>destPos+</code><i>k</I><code>-1</code> and no other |
| * positions of the destination array will have been modified. |
| * (Because of the restrictions already itemized, this |
| * paragraph effectively applies only to the situation where both |
| * arrays have component types that are reference types.) |
| * |
| * @param src the source array. |
| * @param srcPos starting position in the source array. |
| * @param dest the destination array. |
| * @param destPos starting position in the destination data. |
| * @param length the number of array elements to be copied. |
| * @exception IndexOutOfBoundsException if copying would cause |
| * access of data outside array bounds. |
| * @exception ArrayStoreException if an element in the <code>src</code> |
| * array could not be stored into the <code>dest</code> array |
| * because of a type mismatch. |
| * @exception NullPointerException if either <code>src</code> or |
| * <code>dest</code> is <code>null</code>. |
| */ |
| public static native void arraycopy(Object src, int srcPos, |
| Object dest, int destPos, |
| int length); |
| |
| /** |
| * Returns the same hash code for the given object as |
| * would be returned by the default method hashCode(), |
| * whether or not the given object's class overrides |
| * hashCode(). |
| * The hash code for the null reference is zero. |
| * |
| * @param x object for which the hashCode is to be calculated |
| * @return the hashCode |
| * @since JDK1.1 |
| */ |
| public static native int identityHashCode(Object x); |
| |
| /** |
| * System properties. The following properties are guaranteed to be defined: |
| * <dl> |
| * <dt>java.version <dd>Java version number |
| * <dt>java.vendor <dd>Java vendor specific string |
| * <dt>java.vendor.url <dd>Java vendor URL |
| * <dt>java.home <dd>Java installation directory |
| * <dt>java.class.version <dd>Java class version number |
| * <dt>java.class.path <dd>Java classpath |
| * <dt>os.name <dd>Operating System Name |
| * <dt>os.arch <dd>Operating System Architecture |
| * <dt>os.version <dd>Operating System Version |
| * <dt>file.separator <dd>File separator ("/" on Unix) |
| * <dt>path.separator <dd>Path separator (":" on Unix) |
| * <dt>line.separator <dd>Line separator ("\n" on Unix) |
| * <dt>user.name <dd>User account name |
| * <dt>user.home <dd>User home directory |
| * <dt>user.dir <dd>User's current working directory |
| * </dl> |
| */ |
| |
| private static Properties props; |
| private static native Properties initProperties(Properties props); |
| |
| /** |
| * Determines the current system properties. |
| * <p> |
| * First, if there is a security manager, its |
| * <code>checkPropertiesAccess</code> method is called with no |
| * arguments. This may result in a security exception. |
| * <p> |
| * The current set of system properties for use by the |
| * {@link #getProperty(String)} method is returned as a |
| * <code>Properties</code> object. If there is no current set of |
| * system properties, a set of system properties is first created and |
| * initialized. This set of system properties always includes values |
| * for the following keys: |
| * <table summary="Shows property keys and associated values"> |
| * <tr><th>Key</th> |
| * <th>Description of Associated Value</th></tr> |
| * <tr><td><code>java.version</code></td> |
| * <td>Java Runtime Environment version</td></tr> |
| * <tr><td><code>java.vendor</code></td> |
| * <td>Java Runtime Environment vendor</td></tr |
| * <tr><td><code>java.vendor.url</code></td> |
| * <td>Java vendor URL</td></tr> |
| * <tr><td><code>java.home</code></td> |
| * <td>Java installation directory</td></tr> |
| * <tr><td><code>java.vm.specification.version</code></td> |
| * <td>Java Virtual Machine specification version</td></tr> |
| * <tr><td><code>java.vm.specification.vendor</code></td> |
| * <td>Java Virtual Machine specification vendor</td></tr> |
| * <tr><td><code>java.vm.specification.name</code></td> |
| * <td>Java Virtual Machine specification name</td></tr> |
| * <tr><td><code>java.vm.version</code></td> |
| * <td>Java Virtual Machine implementation version</td></tr> |
| * <tr><td><code>java.vm.vendor</code></td> |
| * <td>Java Virtual Machine implementation vendor</td></tr> |
| * <tr><td><code>java.vm.name</code></td> |
| * <td>Java Virtual Machine implementation name</td></tr> |
| * <tr><td><code>java.specification.version</code></td> |
| * <td>Java Runtime Environment specification version</td></tr> |
| * <tr><td><code>java.specification.vendor</code></td> |
| * <td>Java Runtime Environment specification vendor</td></tr> |
| * <tr><td><code>java.specification.name</code></td> |
| * <td>Java Runtime Environment specification name</td></tr> |
| * <tr><td><code>java.class.version</code></td> |
| * <td>Java class format version number</td></tr> |
| * <tr><td><code>java.class.path</code></td> |
| * <td>Java class path</td></tr> |
| * <tr><td><code>java.library.path</code></td> |
| * <td>List of paths to search when loading libraries</td></tr> |
| * <tr><td><code>java.io.tmpdir</code></td> |
| * <td>Default temp file path</td></tr> |
| * <tr><td><code>java.compiler</code></td> |
| * <td>Name of JIT compiler to use</td></tr> |
| * <tr><td><code>java.ext.dirs</code></td> |
| * <td>Path of extension directory or directories</td></tr> |
| * <tr><td><code>os.name</code></td> |
| * <td>Operating system name</td></tr> |
| * <tr><td><code>os.arch</code></td> |
| * <td>Operating system architecture</td></tr> |
| * <tr><td><code>os.version</code></td> |
| * <td>Operating system version</td></tr> |
| * <tr><td><code>file.separator</code></td> |
| * <td>File separator ("/" on UNIX)</td></tr> |
| * <tr><td><code>path.separator</code></td> |
| * <td>Path separator (":" on UNIX)</td></tr> |
| * <tr><td><code>line.separator</code></td> |
| * <td>Line separator ("\n" on UNIX)</td></tr> |
| * <tr><td><code>user.name</code></td> |
| * <td>User's account name</td></tr> |
| * <tr><td><code>user.home</code></td> |
| * <td>User's home directory</td></tr> |
| * <tr><td><code>user.dir</code></td> |
| * <td>User's current working directory</td></tr> |
| * </table> |
| * <p> |
| * Multiple paths in a system property value are separated by the path |
| * separator character of the platform. |
| * <p> |
| * Note that even if the security manager does not permit the |
| * <code>getProperties</code> operation, it may choose to permit the |
| * {@link #getProperty(String)} operation. |
| * |
| * @return the system properties |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPropertiesAccess</code> method doesn't allow access |
| * to the system properties. |
| * @see #setProperties |
| * @see java.lang.SecurityException |
| * @see java.lang.SecurityManager#checkPropertiesAccess() |
| * @see java.util.Properties |
| */ |
| public static Properties getProperties() { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPropertiesAccess(); |
| } |
| |
| return props; |
| } |
| |
| /** |
| * Returns the system-dependent line separator string. It always |
| * returns the same value - the initial value of the {@linkplain |
| * #getProperty(String) system property} {@code line.separator}. |
| * |
| * <p>On UNIX systems, it returns {@code "\n"}; on Microsoft |
| * Windows systems it returns {@code "\r\n"}. |
| */ |
| public static String lineSeparator() { |
| return lineSeparator; |
| } |
| |
| private static String lineSeparator; |
| |
| /** |
| * Sets the system properties to the <code>Properties</code> |
| * argument. |
| * <p> |
| * First, if there is a security manager, its |
| * <code>checkPropertiesAccess</code> method is called with no |
| * arguments. This may result in a security exception. |
| * <p> |
| * The argument becomes the current set of system properties for use |
| * by the {@link #getProperty(String)} method. If the argument is |
| * <code>null</code>, then the current set of system properties is |
| * forgotten. |
| * |
| * @param props the new system properties. |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPropertiesAccess</code> method doesn't allow access |
| * to the system properties. |
| * @see #getProperties |
| * @see java.util.Properties |
| * @see java.lang.SecurityException |
| * @see java.lang.SecurityManager#checkPropertiesAccess() |
| */ |
| public static void setProperties(Properties props) { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPropertiesAccess(); |
| } |
| if (props == null) { |
| props = new Properties(); |
| initProperties(props); |
| } |
| System.props = props; |
| } |
| |
| /** |
| * Gets the system property indicated by the specified key. |
| * <p> |
| * First, if there is a security manager, its |
| * <code>checkPropertyAccess</code> method is called with the key as |
| * its argument. This may result in a SecurityException. |
| * <p> |
| * If there is no current set of system properties, a set of system |
| * properties is first created and initialized in the same manner as |
| * for the <code>getProperties</code> method. |
| * |
| * @param key the name of the system property. |
| * @return the string value of the system property, |
| * or <code>null</code> if there is no property with that key. |
| * |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPropertyAccess</code> method doesn't allow |
| * access to the specified system property. |
| * @exception NullPointerException if <code>key</code> is |
| * <code>null</code>. |
| * @exception IllegalArgumentException if <code>key</code> is empty. |
| * @see #setProperty |
| * @see java.lang.SecurityException |
| * @see java.lang.SecurityManager#checkPropertyAccess(java.lang.String) |
| * @see java.lang.System#getProperties() |
| */ |
| public static String getProperty(String key) { |
| checkKey(key); |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPropertyAccess(key); |
| } |
| |
| return props.getProperty(key); |
| } |
| |
| /** |
| * Gets the system property indicated by the specified key. |
| * <p> |
| * First, if there is a security manager, its |
| * <code>checkPropertyAccess</code> method is called with the |
| * <code>key</code> as its argument. |
| * <p> |
| * If there is no current set of system properties, a set of system |
| * properties is first created and initialized in the same manner as |
| * for the <code>getProperties</code> method. |
| * |
| * @param key the name of the system property. |
| * @param def a default value. |
| * @return the string value of the system property, |
| * or the default value if there is no property with that key. |
| * |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPropertyAccess</code> method doesn't allow |
| * access to the specified system property. |
| * @exception NullPointerException if <code>key</code> is |
| * <code>null</code>. |
| * @exception IllegalArgumentException if <code>key</code> is empty. |
| * @see #setProperty |
| * @see java.lang.SecurityManager#checkPropertyAccess(java.lang.String) |
| * @see java.lang.System#getProperties() |
| */ |
| public static String getProperty(String key, String def) { |
| checkKey(key); |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPropertyAccess(key); |
| } |
| |
| return props.getProperty(key, def); |
| } |
| |
| /** |
| * Sets the system property indicated by the specified key. |
| * <p> |
| * First, if a security manager exists, its |
| * <code>SecurityManager.checkPermission</code> method |
| * is called with a <code>PropertyPermission(key, "write")</code> |
| * permission. This may result in a SecurityException being thrown. |
| * If no exception is thrown, the specified property is set to the given |
| * value. |
| * <p> |
| * |
| * @param key the name of the system property. |
| * @param value the value of the system property. |
| * @return the previous value of the system property, |
| * or <code>null</code> if it did not have one. |
| * |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPermission</code> method doesn't allow |
| * setting of the specified property. |
| * @exception NullPointerException if <code>key</code> or |
| * <code>value</code> is <code>null</code>. |
| * @exception IllegalArgumentException if <code>key</code> is empty. |
| * @see #getProperty |
| * @see java.lang.System#getProperty(java.lang.String) |
| * @see java.lang.System#getProperty(java.lang.String, java.lang.String) |
| * @see java.util.PropertyPermission |
| * @see SecurityManager#checkPermission |
| * @since 1.2 |
| */ |
| public static String setProperty(String key, String value) { |
| checkKey(key); |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(new PropertyPermission(key, |
| SecurityConstants.PROPERTY_WRITE_ACTION)); |
| } |
| |
| return (String) props.setProperty(key, value); |
| } |
| |
| /** |
| * Removes the system property indicated by the specified key. |
| * <p> |
| * First, if a security manager exists, its |
| * <code>SecurityManager.checkPermission</code> method |
| * is called with a <code>PropertyPermission(key, "write")</code> |
| * permission. This may result in a SecurityException being thrown. |
| * If no exception is thrown, the specified property is removed. |
| * <p> |
| * |
| * @param key the name of the system property to be removed. |
| * @return the previous string value of the system property, |
| * or <code>null</code> if there was no property with that key. |
| * |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkPropertyAccess</code> method doesn't allow |
| * access to the specified system property. |
| * @exception NullPointerException if <code>key</code> is |
| * <code>null</code>. |
| * @exception IllegalArgumentException if <code>key</code> is empty. |
| * @see #getProperty |
| * @see #setProperty |
| * @see java.util.Properties |
| * @see java.lang.SecurityException |
| * @see java.lang.SecurityManager#checkPropertiesAccess() |
| * @since 1.5 |
| */ |
| public static String clearProperty(String key) { |
| checkKey(key); |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(new PropertyPermission(key, "write")); |
| } |
| |
| return (String) props.remove(key); |
| } |
| |
| private static void checkKey(String key) { |
| if (key == null) { |
| throw new NullPointerException("key can't be null"); |
| } |
| if (key.equals("")) { |
| throw new IllegalArgumentException("key can't be empty"); |
| } |
| } |
| |
| /** |
| * Gets the value of the specified environment variable. An |
| * environment variable is a system-dependent external named |
| * value. |
| * |
| * <p>If a security manager exists, its |
| * {@link SecurityManager#checkPermission checkPermission} |
| * method is called with a |
| * <code>{@link RuntimePermission}("getenv."+name)</code> |
| * permission. This may result in a {@link SecurityException} |
| * being thrown. If no exception is thrown the value of the |
| * variable <code>name</code> is returned. |
| * |
| * <p><a name="EnvironmentVSSystemProperties"><i>System |
| * properties</i> and <i>environment variables</i></a> are both |
| * conceptually mappings between names and values. Both |
| * mechanisms can be used to pass user-defined information to a |
| * Java process. Environment variables have a more global effect, |
| * because they are visible to all descendants of the process |
| * which defines them, not just the immediate Java subprocess. |
| * They can have subtly different semantics, such as case |
| * insensitivity, on different operating systems. For these |
| * reasons, environment variables are more likely to have |
| * unintended side effects. It is best to use system properties |
| * where possible. Environment variables should be used when a |
| * global effect is desired, or when an external system interface |
| * requires an environment variable (such as <code>PATH</code>). |
| * |
| * <p>On UNIX systems the alphabetic case of <code>name</code> is |
| * typically significant, while on Microsoft Windows systems it is |
| * typically not. For example, the expression |
| * <code>System.getenv("FOO").equals(System.getenv("foo"))</code> |
| * is likely to be true on Microsoft Windows. |
| * |
| * @param name the name of the environment variable |
| * @return the string value of the variable, or <code>null</code> |
| * if the variable is not defined in the system environment |
| * @throws NullPointerException if <code>name</code> is <code>null</code> |
| * @throws SecurityException |
| * if a security manager exists and its |
| * {@link SecurityManager#checkPermission checkPermission} |
| * method doesn't allow access to the environment variable |
| * <code>name</code> |
| * @see #getenv() |
| * @see ProcessBuilder#environment() |
| */ |
| public static String getenv(String name) { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(new RuntimePermission("getenv."+name)); |
| } |
| |
| return ProcessEnvironment.getenv(name); |
| } |
| |
| |
| /** |
| * Returns an unmodifiable string map view of the current system environment. |
| * The environment is a system-dependent mapping from names to |
| * values which is passed from parent to child processes. |
| * |
| * <p>If the system does not support environment variables, an |
| * empty map is returned. |
| * |
| * <p>The returned map will never contain null keys or values. |
| * Attempting to query the presence of a null key or value will |
| * throw a {@link NullPointerException}. Attempting to query |
| * the presence of a key or value which is not of type |
| * {@link String} will throw a {@link ClassCastException}. |
| * |
| * <p>The returned map and its collection views may not obey the |
| * general contract of the {@link Object#equals} and |
| * {@link Object#hashCode} methods. |
| * |
| * <p>The returned map is typically case-sensitive on all platforms. |
| * |
| * <p>If a security manager exists, its |
| * {@link SecurityManager#checkPermission checkPermission} |
| * method is called with a |
| * <code>{@link RuntimePermission}("getenv.*")</code> |
| * permission. This may result in a {@link SecurityException} being |
| * thrown. |
| * |
| * <p>When passing information to a Java subprocess, |
| * <a href=#EnvironmentVSSystemProperties>system properties</a> |
| * are generally preferred over environment variables. |
| * |
| * @return the environment as a map of variable names to values |
| * @throws SecurityException |
| * if a security manager exists and its |
| * {@link SecurityManager#checkPermission checkPermission} |
| * method doesn't allow access to the process environment |
| * @see #getenv(String) |
| * @see ProcessBuilder#environment() |
| * @since 1.5 |
| */ |
| public static java.util.Map<String,String> getenv() { |
| SecurityManager sm = getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(new RuntimePermission("getenv.*")); |
| } |
| |
| return ProcessEnvironment.getenv(); |
| } |
| |
| /** |
| * Terminates the currently running Java Virtual Machine. The |
| * argument serves as a status code; by convention, a nonzero status |
| * code indicates abnormal termination. |
| * <p> |
| * This method calls the <code>exit</code> method in class |
| * <code>Runtime</code>. This method never returns normally. |
| * <p> |
| * The call <code>System.exit(n)</code> is effectively equivalent to |
| * the call: |
| * <blockquote><pre> |
| * Runtime.getRuntime().exit(n) |
| * </pre></blockquote> |
| * |
| * @param status exit status. |
| * @throws SecurityException |
| * if a security manager exists and its <code>checkExit</code> |
| * method doesn't allow exit with the specified status. |
| * @see java.lang.Runtime#exit(int) |
| */ |
| public static void exit(int status) { |
| Runtime.getRuntime().exit(status); |
| } |
| |
| /** |
| * Runs the garbage collector. |
| * <p> |
| * Calling the <code>gc</code> method suggests that the Java Virtual |
| * Machine expend effort toward recycling unused objects in order to |
| * make the memory they currently occupy available for quick reuse. |
| * When control returns from the method call, the Java Virtual |
| * Machine has made a best effort to reclaim space from all discarded |
| * objects. |
| * <p> |
| * The call <code>System.gc()</code> is effectively equivalent to the |
| * call: |
| * <blockquote><pre> |
| * Runtime.getRuntime().gc() |
| * </pre></blockquote> |
| * |
| * @see java.lang.Runtime#gc() |
| */ |
| public static void gc() { |
| Runtime.getRuntime().gc(); |
| } |
| |
| /** |
| * Runs the finalization methods of any objects pending finalization. |
| * <p> |
| * Calling this method suggests that the Java Virtual Machine expend |
| * effort toward running the <code>finalize</code> methods of objects |
| * that have been found to be discarded but whose <code>finalize</code> |
| * methods have not yet been run. When control returns from the |
| * method call, the Java Virtual Machine has made a best effort to |
| * complete all outstanding finalizations. |
| * <p> |
| * The call <code>System.runFinalization()</code> is effectively |
| * equivalent to the call: |
| * <blockquote><pre> |
| * Runtime.getRuntime().runFinalization() |
| * </pre></blockquote> |
| * |
| * @see java.lang.Runtime#runFinalization() |
| */ |
| public static void runFinalization() { |
| Runtime.getRuntime().runFinalization(); |
| } |
| |
| /** |
| * Enable or disable finalization on exit; doing so specifies that the |
| * finalizers of all objects that have finalizers that have not yet been |
| * automatically invoked are to be run before the Java runtime exits. |
| * By default, finalization on exit is disabled. |
| * |
| * <p>If there is a security manager, |
| * its <code>checkExit</code> method is first called |
| * with 0 as its argument to ensure the exit is allowed. |
| * This could result in a SecurityException. |
| * |
| * @deprecated This method is inherently unsafe. It may result in |
| * finalizers being called on live objects while other threads are |
| * concurrently manipulating those objects, resulting in erratic |
| * behavior or deadlock. |
| * @param value indicating enabling or disabling of finalization |
| * @throws SecurityException |
| * if a security manager exists and its <code>checkExit</code> |
| * method doesn't allow the exit. |
| * |
| * @see java.lang.Runtime#exit(int) |
| * @see java.lang.Runtime#gc() |
| * @see java.lang.SecurityManager#checkExit(int) |
| * @since JDK1.1 |
| */ |
| @Deprecated |
| public static void runFinalizersOnExit(boolean value) { |
| Runtime.getRuntime().runFinalizersOnExit(value); |
| } |
| |
| /** |
| * Loads a code file with the specified filename from the local file |
| * system as a dynamic library. The filename |
| * argument must be a complete path name. |
| * <p> |
| * The call <code>System.load(name)</code> is effectively equivalent |
| * to the call: |
| * <blockquote><pre> |
| * Runtime.getRuntime().load(name) |
| * </pre></blockquote> |
| * |
| * @param filename the file to load. |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkLink</code> method doesn't allow |
| * loading of the specified dynamic library |
| * @exception UnsatisfiedLinkError if the file does not exist. |
| * @exception NullPointerException if <code>filename</code> is |
| * <code>null</code> |
| * @see java.lang.Runtime#load(java.lang.String) |
| * @see java.lang.SecurityManager#checkLink(java.lang.String) |
| */ |
| @CallerSensitive |
| public static void load(String filename) { |
| Runtime.getRuntime().load0(Reflection.getCallerClass(), filename); |
| } |
| |
| /** |
| * Loads the system library specified by the <code>libname</code> |
| * argument. The manner in which a library name is mapped to the |
| * actual system library is system dependent. |
| * <p> |
| * The call <code>System.loadLibrary(name)</code> is effectively |
| * equivalent to the call |
| * <blockquote><pre> |
| * Runtime.getRuntime().loadLibrary(name) |
| * </pre></blockquote> |
| * |
| * @param libname the name of the library. |
| * @exception SecurityException if a security manager exists and its |
| * <code>checkLink</code> method doesn't allow |
| * loading of the specified dynamic library |
| * @exception UnsatisfiedLinkError if the library does not exist. |
| * @exception NullPointerException if <code>libname</code> is |
| * <code>null</code> |
| * @see java.lang.Runtime#loadLibrary(java.lang.String) |
| * @see java.lang.SecurityManager#checkLink(java.lang.String) |
| */ |
| @CallerSensitive |
| public static void loadLibrary(String libname) { |
| Runtime.getRuntime().loadLibrary0(Reflection.getCallerClass(), libname); |
| } |
| |
| /** |
| * Maps a library name into a platform-specific string representing |
| * a native library. |
| * |
| * @param libname the name of the library. |
| * @return a platform-dependent native library name. |
| * @exception NullPointerException if <code>libname</code> is |
| * <code>null</code> |
| * @see java.lang.System#loadLibrary(java.lang.String) |
| * @see java.lang.ClassLoader#findLibrary(java.lang.String) |
| * @since 1.2 |
| */ |
| public static native String mapLibraryName(String libname); |
| |
| /** |
| * Initialize the system class. Called after thread initialization. |
| */ |
| private static void initializeSystemClass() { |
| |
| // VM might invoke JNU_NewStringPlatform() to set those encoding |
| // sensitive properties (user.home, user.name, boot.class.path, etc.) |
| // during "props" initialization, in which it may need access, via |
| // System.getProperty(), to the related system encoding property that |
| // have been initialized (put into "props") at early stage of the |
| // initialization. So make sure the "props" is available at the |
| // very beginning of the initialization and all system properties to |
| // be put into it directly. |
| props = new Properties(); |
| initProperties(props); // initialized by the VM |
| |
| // There are certain system configurations that may be controlled by |
| // VM options such as the maximum amount of direct memory and |
| // Integer cache size used to support the object identity semantics |
| // of autoboxing. Typically, the library will obtain these values |
| // from the properties set by the VM. If the properties are for |
| // internal implementation use only, these properties should be |
| // removed from the system properties. |
| // |
| // See java.lang.Integer.IntegerCache and the |
| // sun.misc.VM.saveAndRemoveProperties method for example. |
| // |
| // Save a private copy of the system properties object that |
| // can only be accessed by the internal implementation. Remove |
| // certain system properties that are not intended for public access. |
| sun.misc.VM.saveAndRemoveProperties(props); |
| |
| |
| lineSeparator = props.getProperty("line.separator"); |
| sun.misc.Version.init(); |
| |
| FileInputStream fdIn = new FileInputStream(FileDescriptor.in); |
| FileOutputStream fdOut = new FileOutputStream(FileDescriptor.out); |
| FileOutputStream fdErr = new FileOutputStream(FileDescriptor.err); |
| setIn0(new BufferedInputStream(fdIn)); |
| setOut0(new PrintStream(new BufferedOutputStream(fdOut, 128), true)); |
| setErr0(new PrintStream(new BufferedOutputStream(fdErr, 128), true)); |
| // Load the zip library now in order to keep java.util.zip.ZipFile |
| // from trying to use itself to load this library later. |
| loadLibrary("zip"); |
| |
| // Setup Java signal handlers for HUP, TERM, and INT (where available). |
| Terminator.setup(); |
| |
| // Initialize any miscellenous operating system settings that need to be |
| // set for the class libraries. Currently this is no-op everywhere except |
| // for Windows where the process-wide error mode is set before the java.io |
| // classes are used. |
| sun.misc.VM.initializeOSEnvironment(); |
| |
| // The main thread is not added to its thread group in the same |
| // way as other threads; we must do it ourselves here. |
| Thread current = Thread.currentThread(); |
| current.getThreadGroup().add(current); |
| |
| // register shared secrets |
| setJavaLangAccess(); |
| |
| // Subsystems that are invoked during initialization can invoke |
| // sun.misc.VM.isBooted() in order to avoid doing things that should |
| // wait until the application class loader has been set up. |
| // IMPORTANT: Ensure that this remains the last initialization action! |
| sun.misc.VM.booted(); |
| } |
| |
| private static void setJavaLangAccess() { |
| // Allow privileged classes outside of java.lang |
| sun.misc.SharedSecrets.setJavaLangAccess(new sun.misc.JavaLangAccess(){ |
| public sun.reflect.ConstantPool getConstantPool(Class klass) { |
| return klass.getConstantPool(); |
| } |
| public void setAnnotationType(Class klass, AnnotationType type) { |
| klass.setAnnotationType(type); |
| } |
| public AnnotationType getAnnotationType(Class klass) { |
| return klass.getAnnotationType(); |
| } |
| public <E extends Enum<E>> |
| E[] getEnumConstantsShared(Class<E> klass) { |
| return klass.getEnumConstantsShared(); |
| } |
| public void blockedOn(Thread t, Interruptible b) { |
| t.blockedOn(b); |
| } |
| public void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook) { |
| Shutdown.add(slot, registerShutdownInProgress, hook); |
| } |
| public int getStackTraceDepth(Throwable t) { |
| return t.getStackTraceDepth(); |
| } |
| public StackTraceElement getStackTraceElement(Throwable t, int i) { |
| return t.getStackTraceElement(i); |
| } |
| public int getStringHash32(String string) { |
| return string.hash32(); |
| } |
| }); |
| } |
| } |
