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 * Copyright (c) 2014, 2016, 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
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 */

import java.lang.classfile.*;
import java.lang.classfile.attribute.SourceFileAttribute;
import jdk.internal.classfile.impl.BoundAttribute;

import java.io.InputStream;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.tools.JavaFileObject;

import toolbox.ToolBox;

/**
 * Base class for Source file attribute tests. Checks expected file name for specified classes in the SourceFile attribute.
 * To add new tests you should extend the SourceFileTestBase class and invoke {@link #test} for static sources
 * or {@link #compileAndTest} for generated sources. For more information see corresponding methods.
 *
 * @see #test
 * @see #compileAndTest
 */
public class SourceFileTestBase extends TestBase {
    /**
     * Checks expected fileName for the specified class in the SourceFile attribute.
     *
     * @param classToTest class to check its SourceFile attribute
     * @param fileName    expected name of the file from which the test file is compiled.
     */
    protected void test(Class<?> classToTest, String fileName) throws Exception {
        assertAttributePresent(ClassFile.of().parse(getClassFile(classToTest).toPath()), fileName);
    }

    /**
     * Checks expected fileName for the specified class in the SourceFile attribute.
     *
     * @param classToTest class name to check its SourceFile attribute
     * @param fileName    expected name of the file from which the test file is compiled.
     */
    protected void test(String classToTest, String fileName) throws Exception {
        assertAttributePresent(ClassFile.of().parse(getClassFile(classToTest + ".class").toPath()), fileName);
    }

    /**
     * Checks expected fileName for the specified class in the SourceFile attribute.
     *
     * @param classToTest path of class to check its SourceFile attribute
     * @param fileName    expected name of the file from which the test file is compiled.
     */
    protected void test(Path classToTest, String fileName) throws Exception {
        assertAttributePresent(ClassFile.of().parse(classToTest), fileName);
    }

    /**
     * Compiles sourceCode and for each specified class name checks the SourceFile attribute.
     * The file name is extracted from source code.
     *
     * @param sourceCode    source code to compile
     * @param classesToTest class names to check their SourceFile attribute.
     */
    protected void compileAndTest(String sourceCode, String... classesToTest) throws Exception {

        Map<String, ? extends JavaFileObject> classes = compile(sourceCode).getClasses();
        String fileName = ToolBox.getJavaFileNameFromSource(sourceCode);
        for (String className : classesToTest) {
            ClassModel classFile;
            try (InputStream input = classes.get(className).openInputStream()) {
                classFile = ClassFile.of().parse(input.readAllBytes());
            }
            assertAttributePresent(classFile, fileName);
        }
    }

    private void assertAttributePresent(ClassModel classFile, String fileName) throws Exception {

        //We need to count attributes with the same names because there is no appropriate API in the ClassFile.

        List<SourceFileAttribute> sourceFileAttributes = new ArrayList<>();
        for (Attribute<?> a : classFile.attributes()) {
            if (a instanceof SourceFileAttribute) {
                sourceFileAttributes.add((SourceFileAttribute) a);
            }
        }

        assertEquals(sourceFileAttributes.size(), 1, "Should be the only SourceFile attribute");

        SourceFileAttribute attribute = sourceFileAttributes.get(0);

        assertEquals(attribute.attributeName().stringValue(), Attributes.sourceFile().name(), "Incorrect attribute name");
        assertEquals(attribute.sourceFile().stringValue(), fileName,
                "Incorrect source file name");
        assertEquals(((BoundAttribute<?>)attribute).payloadLen(), 2, "Incorrect attribute length");
    }
}