/*
* Copyright (c) 2005, 2014, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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.
*/
package com.sun.tools.javac.util;
import java.util.HashSet;
import java.util.Set;
import javax.tools.JavaFileObject;
import com.sun.tools.javac.code.Lint.LintCategory;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
/**
* A handler to process mandatory warnings, setting up a deferred diagnostic
* to be printed at the end of the compilation if some warnings get suppressed
* because too many warnings have already been generated.
*
* Note that the SuppressWarnings annotation can be used to suppress warnings
* about conditions that would otherwise merit a warning. Such processing
* is done when the condition is detected, and in those cases, no call is
* made on any API to generate a warning at all. In consequence, this handler only
* Returns to handle those warnings that JLS says must be generated.
*
* <p><b>This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.</b>
*/
public class MandatoryWarningHandler {
/**
* The kinds of different deferred diagnostics that might be generated
* if a mandatory warning is suppressed because too many warnings have
* already been output.
*
* The parameter is a fragment used to build an I18N message key for Log.
*/
private enum DeferredDiagnosticKind {
/**
* This kind is used when a single specific file is found to have warnings
* and no similar warnings have already been given.
* It generates a message like:
* FILE has ISSUES
*/
IN_FILE(".filename"),
/**
* This kind is used when a single specific file is found to have warnings
* and when similar warnings have already been reported for the file.
* It generates a message like:
* FILE has additional ISSUES
*/
ADDITIONAL_IN_FILE(".filename.additional"),
/**
* This kind is used when multiple files have been found to have warnings,
* and none of them have had any similar warnings.
* It generates a message like:
* Some files have ISSUES
*/
IN_FILES(".plural"),
/**
* This kind is used when multiple files have been found to have warnings,
* and some of them have had already had specific similar warnings.
* It generates a message like:
* Some files have additional ISSUES
*/
ADDITIONAL_IN_FILES(".plural.additional");
DeferredDiagnosticKind(String v) { value = v; }
String getKey(String prefix) { return prefix + value; }
private final String value;
}
/**
* Create a handler for mandatory warnings.
* @param log The log on which to generate any diagnostics
* @param verbose Specify whether or not detailed messages about
* individual instances should be given, or whether an aggregate
* message should be generated at the end of the compilation.
* Typically set via -Xlint:option.
* @param enforceMandatory
* True if mandatory warnings and notes are being enforced.
* @param prefix A common prefix for the set of message keys for
* the messages that may be generated.
* @param lc An associated lint category for the warnings, or null if none.
*/
public MandatoryWarningHandler(Log log, boolean verbose,
boolean enforceMandatory, String prefix,
LintCategory lc) {
this.log = log;
this.verbose = verbose;
this.prefix = prefix;
this.enforceMandatory = enforceMandatory;
this.lintCategory = lc;
}
/**
* Report a mandatory warning.
*/
public void report(DiagnosticPosition pos, String msg, Object... args) {
JavaFileObject currentSource = log.currentSourceFile();
if (verbose) {
if (sourcesWithReportedWarnings == null)
sourcesWithReportedWarnings = new HashSet<>();
if (log.nwarnings < log.MaxWarnings) {
// generate message and remember the source file
logMandatoryWarning(pos, msg, args);
sourcesWithReportedWarnings.add(currentSource);
} else if (deferredDiagnosticKind == null) {
// set up deferred message
if (sourcesWithReportedWarnings.contains(currentSource)) {
// more errors in a file that already has reported warnings
deferredDiagnosticKind = DeferredDiagnosticKind.ADDITIONAL_IN_FILE;
} else {
// warnings in a new source file
deferredDiagnosticKind = DeferredDiagnosticKind.IN_FILE;
}
deferredDiagnosticSource = currentSource;
deferredDiagnosticArg = currentSource;
} else if ((deferredDiagnosticKind == DeferredDiagnosticKind.IN_FILE
|| deferredDiagnosticKind == DeferredDiagnosticKind.ADDITIONAL_IN_FILE)
&& !equal(deferredDiagnosticSource, currentSource)) {
// additional errors in more than one source file
deferredDiagnosticKind = DeferredDiagnosticKind.ADDITIONAL_IN_FILES;
deferredDiagnosticArg = null;
}
} else {
if (deferredDiagnosticKind == null) {
// warnings in a single source
deferredDiagnosticKind = DeferredDiagnosticKind.IN_FILE;
deferredDiagnosticSource = currentSource;
deferredDiagnosticArg = currentSource;
} else if (deferredDiagnosticKind == DeferredDiagnosticKind.IN_FILE &&
!equal(deferredDiagnosticSource, currentSource)) {
// warnings in multiple source files
deferredDiagnosticKind = DeferredDiagnosticKind.IN_FILES;
deferredDiagnosticArg = null;
}
}
}
/**
* Report any diagnostic that might have been deferred by previous calls of report().
*/
public void reportDeferredDiagnostic() {
if (deferredDiagnosticKind != null) {
if (deferredDiagnosticArg == null)
logMandatoryNote(deferredDiagnosticSource, deferredDiagnosticKind.getKey(prefix));
else
logMandatoryNote(deferredDiagnosticSource, deferredDiagnosticKind.getKey(prefix), deferredDiagnosticArg);
if (!verbose)
logMandatoryNote(deferredDiagnosticSource, prefix + ".recompile");
}
}
/**
* Check two objects, each possibly null, are either both null or are equal.
*/
private static boolean equal(Object o1, Object o2) {
return ((o1 == null || o2 == null) ? (o1 == o2) : o1.equals(o2));
}
/**
* The log to which to report warnings.
*/
private Log log;
/**
* Whether or not to report individual warnings, or simply to report a
* single aggregate warning at the end of the compilation.
*/
private boolean verbose;
/**
* The common prefix for all I18N message keys generated by this handler.
*/
private String prefix;
/**
* A set containing the names of the source files for which specific
* warnings have been generated -- i.e. in verbose mode. If a source name
* appears in this list, then deferred diagnostics will be phrased to
* include "additionally"...
*/
private Set<JavaFileObject> sourcesWithReportedWarnings;
/**
* A variable indicating the latest best guess at what the final
* deferred diagnostic will be. Initially as specific and helpful
* as possible, as more warnings are reported, the scope of the
* diagnostic will be broadened.
*/
private DeferredDiagnosticKind deferredDiagnosticKind;
/**
* If deferredDiagnosticKind is IN_FILE or ADDITIONAL_IN_FILE, this variable
* gives the value of log.currentSource() for the file in question.
*/
private JavaFileObject deferredDiagnosticSource;
/**
* An optional argument to be used when constructing the
* deferred diagnostic message, based on deferredDiagnosticKind.
* This variable should normally be set/updated whenever
* deferredDiagnosticKind is updated.
*/
private Object deferredDiagnosticArg;
/**
* True if mandatory warnings and notes are being enforced.
*/
private final boolean enforceMandatory;
/**
* A LintCategory to be included in point-of-use diagnostics to indicate
* how messages might be suppressed (i.e. with @SuppressWarnings).
*/
private final LintCategory lintCategory;
/**
* Reports a mandatory warning to the log. If mandatory warnings
* are not being enforced, treat this as an ordinary warning.
*/
private void logMandatoryWarning(DiagnosticPosition pos, String msg,
Object... args) {
// Note: the following log methods are safe if lintCategory is null.
if (enforceMandatory)
log.mandatoryWarning(lintCategory, pos, msg, args);
else
log.warning(lintCategory, pos, msg, args);
}
/**
* Reports a mandatory note to the log. If mandatory notes are
* not being enforced, treat this as an ordinary note.
*/
private void logMandatoryNote(JavaFileObject file, String msg, Object... args) {
if (enforceMandatory)
log.mandatoryNote(file, msg, args);
else
log.note(file, msg, args);
}
}