Java example source code file (T7005371.java)

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Java - Java tags/keywords

classfile, code, code_attribute, error, exception, file, localvariabletypetable, localvariabletypetable_attribute, lvt_length, lvt_sig_type, missing, string, subtest_name, test_method_name

The T7005371.java Java example source code

/*
 * Copyright (c) 2010, 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
 * @bug 7005371
 * @summary  Multicatch: assertion error while generating LocalVariableTypeTable attribute
 * @compile -g SubTest.java
 * @run main T7005371
 */

import com.sun.tools.classfile.Attribute;
import com.sun.tools.classfile.ClassFile;
import com.sun.tools.classfile.Code_attribute;
import com.sun.tools.classfile.LocalVariableTypeTable_attribute;
import com.sun.tools.classfile.Method;

import java.io.*;

public class T7005371 {

    static final String SUBTEST_NAME = SubTest.class.getName() + ".class";
    static final String TEST_METHOD_NAME = "test";
    static final int LVT_LENGTH = 1;
    static final String LVT_SIG_TYPE = "Ljava/util/List<Ljava/lang/String;>;";


    public static void main(String... args) throws Exception {
        new T7005371().run();
    }

    public void run() throws Exception {
        String workDir = System.getProperty("test.classes");
        System.out.println(workDir);
        File compiledTest = new File(workDir, SUBTEST_NAME);
        verifyLocalVariableTypeTableAttr(compiledTest);
    }

    void verifyLocalVariableTypeTableAttr(File f) {
        System.err.println("verify: " + f);
        try {
            ClassFile cf = ClassFile.read(f);
            Method testMethod = null;
            for (Method m : cf.methods) {
                if (m.getName(cf.constant_pool).equals(TEST_METHOD_NAME)) {
                    testMethod = m;
                    break;
                }
            }
            if (testMethod == null) {
                throw new Error("Missing method: " + TEST_METHOD_NAME);
            }
            Code_attribute code = (Code_attribute)testMethod.attributes.get(Attribute.Code);
            if (code == null) {
                throw new Error("Missing Code attribute for method: " + TEST_METHOD_NAME);
            }
            LocalVariableTypeTable_attribute lvt_table =
                    (LocalVariableTypeTable_attribute)code.attributes.get(Attribute.LocalVariableTypeTable);
            if (lvt_table == null) {
                throw new Error("Missing LocalVariableTypeTable attribute for method: " + TEST_METHOD_NAME);
            }
            if (lvt_table.local_variable_table_length != LVT_LENGTH) {
                throw new Error("LocalVariableTypeTable has wrong size" +
                        "\nfound: " + lvt_table.local_variable_table_length +
                        "\nrequired: " + LVT_LENGTH);
            }
            String sig =
                    cf.constant_pool.getUTF8Value(lvt_table.local_variable_table[0].signature_index);

            if (sig == null || !sig.equals(LVT_SIG_TYPE)) {
                throw new Error("LocalVariableTypeTable has wrong signature" +
                        "\nfound: " + sig +
                        "\nrequired: " + LVT_SIG_TYPE);
            }
        } catch (Exception e) {
            e.printStackTrace();
            throw new Error("error reading " + f +": " + e);
        }
    }
}