Bug ID: JDK-6971877 Project Coin: improve semantics of suppressed exceptions in try-with-resources

Type: Bug
Component: tools
Sub-Component: javac
Affected Version: 7

Priority: P3
Status: Closed
Resolution: Fixed
OS: generic
CPU: generic

Submitted: 2010-07-23
Updated: 2017-05-16
Resolved: 2011-03-07

JDK 7
7 b105Fixed

After additional analysis, the initialy proposed translation semantics for try-with-resources into other statements is suboptimal: rather than only supressing a java.langException (or subclass) any Throwable should be suppressed.  See option 1 discussed in
http://blogs.sun.com/darcy/entry/project_coin_updated_arm_spec

PUBLIC COMMENTS See

02-08-2010

SUGGESTED FIX --- /dev/null 2009-07-06 20:02:10.000000000 -0700 +++ new/test/tools/javac/TryWithResources/TwrSuppression.java 2010-08-02 11:43:53.000000000 -0700 @@ -0,0 +1,67 @@ +/* + * 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 6971877 + * @author Joseph D. Darcy + * @summary Verify a primary exception suppresses all throwables + */ + +public class TwrSuppression implements AutoCloseable { + public static void main(String... args) throws Throwable { + try { + try (TwrSuppression r1 = new TwrSuppression(false); + TwrSuppression r2 = new TwrSuppression(true)) { + throw new RuntimeException(); + } + } catch(RuntimeException e) { + Throwable[] suppressedExceptions = e.getSuppressedExceptions(); + int length = suppressedExceptions.length; + if (length != 2) + throw new RuntimeException("Unexpected length " + length); + + if (suppressedExceptions[0].getClass() != Error.class || + suppressedExceptions[1].getClass() != Exception.class) { + System.err.println("Unexpected suppressed types!"); + e.printStackTrace(); + throw new RuntimeException(e); + } + } + } + + private boolean throwError; + + private TwrSuppression(boolean throwError) { + this.throwError = throwError; + } + + @Override + public void close() throws Exception { + if (throwError) { + throw new Error(); + } else { + throw new Exception(); + } + } +}

02-08-2010

EVALUATION Yes.

23-07-2010

Relates :	JDK-7013420 - Project Coin: remove general expression support from try-with-resources statement
Relates :	JDK-7020047 - Project Coin: generate null-check around try-with-resources close call
Relates :	JDK-6911256 - Project Coin: Support Automatic Resource Management (ARM) blocks in the compiler
Relates :	JDK-4988583 - AutomaticException chaining for exception in try and exception thrown in finally