| /* |
| * Copyright (c) 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test |
| * @bug 7020499 |
| * @summary Verify that try-with-resources desugaring is not generating unnecessary null checks |
| * @library /tools/lib |
| * @modules jdk.compiler/com.sun.tools.javac.api |
| * jdk.compiler/com.sun.tools.javac.code |
| * jdk.compiler/com.sun.tools.javac.comp |
| * jdk.compiler/com.sun.tools.javac.main |
| * jdk.compiler/com.sun.tools.javac.tree |
| * jdk.compiler/com.sun.tools.javac.util |
| * @build toolbox.ToolBox toolbox.JavacTask TwrAvoidNullCheck |
| * @run main TwrAvoidNullCheck |
| */ |
| |
| import java.io.IOException; |
| import java.util.Arrays; |
| |
| import com.sun.source.util.JavacTask; |
| import com.sun.tools.javac.api.JavacTool; |
| import com.sun.tools.javac.comp.AttrContext; |
| import com.sun.tools.javac.comp.Env; |
| import com.sun.tools.javac.comp.Lower; |
| import com.sun.tools.javac.tree.JCTree; |
| import com.sun.tools.javac.tree.JCTree.JCBinary; |
| import com.sun.tools.javac.tree.TreeInfo; |
| import com.sun.tools.javac.tree.TreeMaker; |
| import com.sun.tools.javac.tree.TreeScanner; |
| import com.sun.tools.javac.util.Context; |
| import com.sun.tools.javac.util.Context.Factory; |
| import com.sun.tools.javac.util.List; |
| |
| import toolbox.ToolBox; |
| |
| public class TwrAvoidNullCheck { |
| public static void main(String... args) throws IOException { |
| new TwrAvoidNullCheck().run(); |
| } |
| void run() throws IOException { |
| run("new Test()", false); |
| run("null", true); |
| run("System.getProperty(\"test\") != null ? new Test() : null", true); |
| } |
| void run(String resourceSpecification, boolean expected) throws IOException { |
| String template = "public class Test implements AutoCloseable {\n" + |
| " void t() {\n" + |
| " try (Test resource = RESOURCE) { }\n" + |
| " }\n" + |
| " public void close() { }\n" + |
| "}\n"; |
| String code = template.replace("RESOURCE", resourceSpecification); |
| Context ctx = new Context(); |
| DumpLower.preRegister(ctx); |
| Iterable<ToolBox.JavaSource> files = Arrays.asList(new ToolBox.JavaSource(code)); |
| JavacTask task = JavacTool.create().getTask(null, null, null, null, null, files, ctx); |
| task.call(); |
| |
| boolean hasNullCheck = ((DumpLower) DumpLower.instance(ctx)).hasNullCheck; |
| |
| if (hasNullCheck != expected) { |
| throw new IllegalStateException("expected: " + expected + |
| "; actual: " + hasNullCheck + |
| "; code: " + code); |
| } |
| } |
| |
| static class DumpLower extends Lower { |
| |
| public static void preRegister(Context ctx) { |
| ctx.put(lowerKey, new Factory<Lower>() { |
| @Override |
| public Lower make(Context c) { |
| return new DumpLower(c); |
| } |
| }); |
| } |
| |
| public DumpLower(Context context) { |
| super(context); |
| } |
| |
| boolean hasNullCheck; |
| |
| @Override |
| public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) { |
| List<JCTree> result = super.translateTopLevelClass(env, cdef, make); |
| |
| new TreeScanner() { |
| @Override |
| public void visitBinary(JCBinary tree) { |
| hasNullCheck |= tree.operator.getSimpleName().contentEquals("!=") && |
| "resource".equals(String.valueOf(TreeInfo.name(tree.lhs))) && |
| TreeInfo.isNull(tree.rhs); |
| super.visitBinary(tree); |
| } |
| }.scan(result); |
| |
| return result; |
| } |
| |
| } |
| } |