Java example source code file (ImplementationCacheTest.java)

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Java - Java tags/keywords

assertionerror, charsequence, context, element, i_m, javactask, javafileobject, methodsymbol, net, network, sourcefile, string, symbol, types, util

The ImplementationCacheTest.java Java example source code

/*
 * Copyright (c) 2011, 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 7017664
 * @summary Basher for CompoundScopes
 */

import com.sun.source.util.JavacTask;
import com.sun.tools.javac.code.Symbol;
import com.sun.tools.javac.code.Types;
import com.sun.tools.javac.file.JavacFileManager;
import com.sun.tools.javac.util.Context;

import com.sun.tools.javac.code.Symbol.*;

import java.io.IOException;
import java.net.URI;
import java.util.Arrays;
import java.util.List;
import javax.lang.model.element.Element;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.ToolProvider;

import static javax.tools.JavaFileObject.Kind;

public class ImplementationCacheTest {

    static class SourceFile extends SimpleJavaFileObject {

        final String source = "interface I { void m(); }\n" +
                              "class A implements I { public void m() {} }\n" +
                              "class B extends A { }\n";

        public SourceFile() {
            super(URI.create("test.java"), Kind.SOURCE);
        }

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {
            return source;
        }
    }

    public static void main(String[] args) throws IOException {
        List<? extends JavaFileObject> files = Arrays.asList(new SourceFile());
        JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
        JavacTask ct = (JavacTask)tool.getTask(null, null, null, null, null, files);
        Context ctx = new Context();
        JavacFileManager.preRegister(ctx);
        checkImplementationCache(ct.analyze(), Types.instance(ctx));
    }

    static void checkImplementationCache(Iterable<? extends Element> elements, Types types) {
        if (types == null) {
            throw new AssertionError("problems initializing Types");
        }

        Symbol a = null;
        Symbol b = null;
        Symbol i = null;

        for (Element e : elements) {
            if (e.getSimpleName().contentEquals("A")) {
                a = (Symbol)e;
            } else if (e.getSimpleName().contentEquals("B")) {
                b = (Symbol)e;
            } else if (e.getSimpleName().contentEquals("I")) {
                i = (Symbol)e;
            }
        }

        if (a == null || b == null || i == null) {
            throw new AssertionError("missing class");
        }

        MethodSymbol I_m = null;

        for (Symbol sym : i.members().getElements()) {
            if (sym.name.contentEquals("m")) {
                I_m = (MethodSymbol)sym;
            }
        }

        if (I_m == null) {
            throw new AssertionError("missing method m() in scope of interface I");
        }

        Symbol impl = I_m.implementation((TypeSymbol)b, types, true);

        if (impl == null || impl.owner != a) {
            throw new AssertionError("wrong implementation for m() in B");
        }

        b.members().enter(I_m.clone(b));

        Symbol newImpl = I_m.implementation((TypeSymbol)b, types, true);

        if (newImpl == impl) {
            throw new AssertionError("stale implementation for m() in B");
        }

        if (newImpl == null || newImpl.owner != b) {
            throw new AssertionError("wrong implementation for m() in B");
        }
    }
}