openjdk/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleStatics.java

/*
 * Copyright (c) 2011, 2015, 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
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 * questions.
 */

package java.lang.invoke;

import java.security.AccessController;
import java.security.PrivilegedAction;
import jdk.internal.misc.Unsafe;

/**
 * This class consists exclusively of static names internal to the
 * method handle implementation.
 * Usage:  {@code import static java.lang.invoke.MethodHandleStatics.*}
 * @author John Rose, JSR 292 EG
 */
/*non-public*/ class MethodHandleStatics {

    private MethodHandleStatics() { }  // do not instantiate

    static final Unsafe UNSAFE = Unsafe.getUnsafe();

    static final boolean DEBUG_METHOD_HANDLE_NAMES;
    static final boolean DUMP_CLASS_FILES;
    static final boolean TRACE_INTERPRETER;
    static final boolean TRACE_METHOD_LINKAGE;
    static final int COMPILE_THRESHOLD;
    static final int DONT_INLINE_THRESHOLD;
    static final int PROFILE_LEVEL;
    static final boolean PROFILE_GWT;
    static final int CUSTOMIZE_THRESHOLD;

    static {
        final Object[] values = new Object[9];
        AccessController.doPrivileged(new PrivilegedAction<>() {
                public Void run() {
                    values[0] = Boolean.getBoolean("java.lang.invoke.MethodHandle.DEBUG_NAMES");
                    values[1] = Boolean.getBoolean("java.lang.invoke.MethodHandle.DUMP_CLASS_FILES");
                    values[2] = Boolean.getBoolean("java.lang.invoke.MethodHandle.TRACE_INTERPRETER");
                    values[3] = Boolean.getBoolean("java.lang.invoke.MethodHandle.TRACE_METHOD_LINKAGE");
                    values[4] = Integer.getInteger("java.lang.invoke.MethodHandle.COMPILE_THRESHOLD", 0);
                    values[5] = Integer.getInteger("java.lang.invoke.MethodHandle.DONT_INLINE_THRESHOLD", 30);
                    values[6] = Integer.getInteger("java.lang.invoke.MethodHandle.PROFILE_LEVEL", 0);
                    values[7] = Boolean.parseBoolean(System.getProperty("java.lang.invoke.MethodHandle.PROFILE_GWT", "true"));
                    values[8] = Integer.getInteger("java.lang.invoke.MethodHandle.CUSTOMIZE_THRESHOLD", 127);
                    return null;
                }
            });
        DEBUG_METHOD_HANDLE_NAMES = (Boolean) values[0];
        DUMP_CLASS_FILES          = (Boolean) values[1];
        TRACE_INTERPRETER         = (Boolean) values[2];
        TRACE_METHOD_LINKAGE      = (Boolean) values[3];
        COMPILE_THRESHOLD         = (Integer) values[4];
        DONT_INLINE_THRESHOLD     = (Integer) values[5];
        PROFILE_LEVEL             = (Integer) values[6];
        PROFILE_GWT               = (Boolean) values[7];
        CUSTOMIZE_THRESHOLD       = (Integer) values[8];

        if (CUSTOMIZE_THRESHOLD < -1 || CUSTOMIZE_THRESHOLD > 127) {
            throw newInternalError("CUSTOMIZE_THRESHOLD should be in [-1...127] range");
        }
    }

    /** Tell if any of the debugging switches are turned on.
     *  If this is the case, it is reasonable to perform extra checks or save extra information.
     */
    /*non-public*/ static boolean debugEnabled() {
        return (DEBUG_METHOD_HANDLE_NAMES |
                DUMP_CLASS_FILES |
                TRACE_INTERPRETER |
                TRACE_METHOD_LINKAGE);
    }

    // handy shared exception makers (they simplify the common case code)
    /*non-public*/ static InternalError newInternalError(String message) {
        return new InternalError(message);
    }
    /*non-public*/ static InternalError newInternalError(String message, Throwable cause) {
        return new InternalError(message, cause);
    }
    /*non-public*/ static InternalError newInternalError(Throwable cause) {
        return new InternalError(cause);
    }
    /*non-public*/ static RuntimeException newIllegalStateException(String message) {
        return new IllegalStateException(message);
    }
    /*non-public*/ static RuntimeException newIllegalStateException(String message, Object obj) {
        return new IllegalStateException(message(message, obj));
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message) {
        return new IllegalArgumentException(message);
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message, Object obj) {
        return new IllegalArgumentException(message(message, obj));
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message, Object obj, Object obj2) {
        return new IllegalArgumentException(message(message, obj, obj2));
    }
    /** Propagate unchecked exceptions and errors, but wrap anything checked and throw that instead. */
    /*non-public*/ static Error uncaughtException(Throwable ex) {
        if (ex instanceof Error)  throw (Error) ex;
        if (ex instanceof RuntimeException)  throw (RuntimeException) ex;
        throw newInternalError("uncaught exception", ex);
    }
    private static String message(String message, Object obj) {
        if (obj != null)  message = message + ": " + obj;
        return message;
    }
    private static String message(String message, Object obj, Object obj2) {
        if (obj != null || obj2 != null)  message = message + ": " + obj + ", " + obj2;
        return message;
    }
}