Java example source code file (Util.java)

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Java - Java tags/keywords

assertionerror, classdoc, javadoc, parameter, string, type, util

The Util.java Java example source code

/*
 * Copyright (c) 2003, 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 sun.rmi.rmic.newrmic.jrmp;

import com.sun.javadoc.ClassDoc;
import com.sun.javadoc.MethodDoc;
import com.sun.javadoc.Parameter;
import com.sun.javadoc.Type;

/**
 * Provides static utility methods.
 *
 * WARNING: The contents of this source file are not part of any
 * supported API.  Code that depends on them does so at its own risk:
 * they are subject to change or removal without notice.
 *
 * @author Peter Jones
 **/
final class Util {

    private Util() { throw new AssertionError(); }

    /**
     * Returns the binary name of the class or interface represented
     * by the specified ClassDoc.
     **/
    static String binaryNameOf(ClassDoc cl) {
        String flat = cl.name().replace('.', '$');
        String packageName = cl.containingPackage().name();
        return packageName.equals("") ? flat : packageName + "." + flat;
    }

    /**
     * Returns the method descriptor for the specified method.
     *
     * See section 4.3.3 of The Java Virtual Machine Specification
     * Second Edition for the definition of a "method descriptor".
     **/
    static String methodDescriptorOf(MethodDoc method) {
        String desc = "(";
        Parameter[] parameters = method.parameters();
        for (int i = 0; i < parameters.length; i++) {
            desc += typeDescriptorOf(parameters[i].type());
        }
        desc += ")" + typeDescriptorOf(method.returnType());
        return desc;
    }

    /**
     * Returns the descriptor for the specified type, as appropriate
     * for either a parameter or return type in a method descriptor.
     **/
    private static String typeDescriptorOf(Type type) {
        String desc;
        ClassDoc classDoc = type.asClassDoc();
        if (classDoc == null) {
            /*
             * Handle primitive types.
             */
            String name = type.typeName();
            if (name.equals("boolean")) {
                desc = "Z";
            } else if (name.equals("byte")) {
                desc = "B";
            } else if (name.equals("char")) {
                desc = "C";
            } else if (name.equals("short")) {
                desc = "S";
            } else if (name.equals("int")) {
                desc = "I";
            } else if (name.equals("long")) {
                desc = "J";
            } else if (name.equals("float")) {
                desc = "F";
            } else if (name.equals("double")) {
                desc = "D";
            } else if (name.equals("void")) {
                desc = "V";
            } else {
                throw new AssertionError(
                    "unrecognized primitive type: " + name);
            }
        } else {
            /*
             * Handle non-array reference types.
             */
            desc = "L" + binaryNameOf(classDoc).replace('.', '/') + ";";
        }

        /*
         * Handle array types.
         */
        int dimensions = type.dimension().length() / 2;
        for (int i = 0; i < dimensions; i++) {
            desc = "[" + desc;
        }

        return desc;
    }

    /**
     * Returns a reader-friendly string representation of the
     * specified method's signature.  Names of reference types are not
     * package-qualified.
     **/
    static String getFriendlyUnqualifiedSignature(MethodDoc method) {
        String sig = method.name() + "(";
        Parameter[] parameters = method.parameters();
        for (int i = 0; i < parameters.length; i++) {
            if (i > 0) {
                sig += ", ";
            }
            Type paramType = parameters[i].type();
            sig += paramType.typeName() + paramType.dimension();
        }
        sig += ")";
        return sig;
    }

    /**
     * Returns true if the specified type is void.
     **/
    static boolean isVoid(Type type) {
        return type.asClassDoc() == null && type.typeName().equals("void");
    }
}