Java example source code file (T6716452.java)

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Java - Java tags/keywords

attribute, bufferedwriter, classfile, code, constantpoolexception, error, exception, file, filewriter, method, printwriter, string, t6716452, test

The T6716452.java Java example source code

/*
 * Copyright (c) 2008, 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.
 *
 * 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.
 */

/*
 * @test 6716452
 * @summary need a method to get an index of an attribute
 */

import java.io.*;
import com.sun.tools.classfile.*;

public class T6716452 {
    public static void main(String[] args) throws Exception {
        new T6716452().run();
    }

    public void run() throws Exception {
        File javaFile = writeTestFile();
        File classFile = compileTestFile(javaFile);

        ClassFile cf = ClassFile.read(classFile);
        for (Method m: cf.methods) {
            test(cf, m);
        }

        if (errors > 0)
            throw new Exception(errors + " errors found");
    }

    void test(ClassFile cf, Method m) {
        test(cf, m, Attribute.Code, Code_attribute.class);
        test(cf, m, Attribute.Exceptions, Exceptions_attribute.class);
    }

    // test the result of Attributes.getIndex according to expectations
    // encoded in the method's name
    void test(ClassFile cf, Method m, String name, Class<?> c) {
        int index = m.attributes.getIndex(cf.constant_pool, name);
        try {
            String m_name = m.getName(cf.constant_pool);
            System.err.println("Method " + m_name + " name:" + name + " index:" + index + " class: " + c);
            boolean expect = (m_name.equals("<init>") && name.equals("Code"))
                || (m_name.indexOf(name) != -1);
            boolean found = (index != -1);
            if (expect) {
                if (found) {
                    Attribute attr = m.attributes.get(index);
                    if (!c.isAssignableFrom(attr.getClass())) {
                        error(m + ": unexpected attribute found,"
                              + " expected " + c.getName()
                              + " found " + attr.getClass().getName());
                    }
                } else {
                    error(m + ": expected attribute " + name + " not found");
                }
            } else {
                if (found) {
                    error(m + ": unexpected attribute " + name);
                }
            }
        } catch (ConstantPoolException e) {
            error(m + ": " + e);
        }
    }

    File writeTestFile() throws IOException {
        File f = new File("Test.java");
        PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(f)));
        out.println("abstract class Test { ");
        out.println("  abstract void m();");
        out.println("  void m_Code() { }");
        out.println("  abstract void m_Exceptions() throws Exception;");
        out.println("  void m_Code_Exceptions() throws Exception { }");
        out.println("}");
        out.close();
        return f;
    }

    File compileTestFile(File f) {
        int rc = com.sun.tools.javac.Main.compile(new String[] { "-g", f.getPath() });
        if (rc != 0)
            throw new Error("compilation failed. rc=" + rc);
        String path = f.getPath();
        return new File(path.substring(0, path.length() - 5) + ".class");
    }

    void error(String msg) {
        System.err.println("error: " + msg);
        errors++;
    }

    int errors;
}