/*
* @(#)Compiler.java 1.20 04/05/05
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.lang;
/**
* The <code>Compiler</code> class is provided to support
* Java-to-native-code compilers and related services. By design, the
* <code>Compiler</code> class does nothing; it serves as a
* placeholder for a JIT compiler implementation.
* <p>
* When the Java Virtual Machine first starts, it determines if the
* system property <code>java.compiler</code> exists. (System
* properties are accessible through <code>getProperty</code> and ,
* a method defined by the <code>System</code> class.) If so, it is
* assumed to be the name of a library (with a platform-dependent
* exact location and type); the <code>loadLibrary</code> method in
* class <code>System</code> is called to load that library. If this
* loading succeeds, the function named
* <code>java_lang_Compiler_start()</code> in that library is called.
* <p>
* If no compiler is available, these methods do nothing.
*
* @author Frank Yellin
* @version 1.20, 05/05/04
* @see java.lang.System#getProperty(java.lang.String)
* @see java.lang.System#getProperty(java.lang.String, java.lang.String)
* @see java.lang.System#loadLibrary(java.lang.String)
* @since JDK1.0
*/
public final class Compiler {
private Compiler() {} // don't make instances
private static native void initialize();
private static native void registerNatives();
static {
registerNatives();
java.security.AccessController.doPrivileged
(new java.security.PrivilegedAction() {
public Object run() {
boolean loaded = false;
String jit = System.getProperty("java.compiler");
if ((jit != null) && (!jit.equals("NONE")) &&
(!jit.equals("")))
{
try {
System.loadLibrary(jit);
initialize();
loaded = true;
} catch (UnsatisfiedLinkError e) {
System.err.println("Warning: JIT compiler \"" +
jit + "\" not found. Will use interpreter.");
}
}
String info = System.getProperty("java.vm.info");
if (loaded) {
System.setProperty("java.vm.info", info + ", " + jit);
} else {
System.setProperty("java.vm.info", info + ", nojit");
}
return null;
}
});
}
/**
* Compiles the specified class.
*
* @param clazz a class.
* @return <code>true</code> if the compilation succeeded;
* <code>false</code> if the compilation failed or no compiler
* is available.
* @exception NullPointerException if <code>clazz</code> is
* <code>null</code>.
*/
public static native boolean compileClass(Class<?> clazz);
/**
* Compiles all classes whose name matches the specified string.
*
* @param string the name of the classes to compile.
* @return <code>true</code> if the compilation succeeded;
* <code>false</code> if the compilation failed or no compiler
* is available.
* @exception NullPointerException if <code>string</code> is
* <code>null</code>.
*/
public static native boolean compileClasses(String string);
/**
* Examines the argument type and its fields and perform some documented
* operation. No specific operations are required.
*
* @param any an argument.
* @return a compiler-specific value, or <code>null</code> if no compiler
* is available.
* @exception NullPointerException if <code>any</code> is
* <code>null</code>.
*/
public static native Object command(Object any);
/**
* Cause the Compiler to resume operation.
*/
public static native void enable();
/**
* Cause the Compiler to cease operation.
*/
public static native void disable();
}
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