| /** |
| * Copyright (C) 2006 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.inject.internal.util; |
| |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.collect.Lists; |
| |
| import java.util.List; |
| |
| /** |
| * Provides access to the calling line of code. |
| * |
| * @author crazybob@google.com (Bob Lee) |
| */ |
| public final class SourceProvider { |
| |
| /** Indicates that the source is unknown. */ |
| public static final Object UNKNOWN_SOURCE = "[unknown source]"; |
| |
| private final SourceProvider parent; |
| private final ImmutableSet<String> classNamesToSkip; |
| |
| public static final SourceProvider DEFAULT_INSTANCE |
| = new SourceProvider(ImmutableSet.of(SourceProvider.class.getName())); |
| |
| private SourceProvider(Iterable<String> classesToSkip) { |
| this(null, classesToSkip); |
| } |
| |
| private SourceProvider(SourceProvider parent, Iterable<String> classesToSkip) { |
| this.parent = parent; |
| |
| ImmutableSet.Builder<String> classNamesToSkipBuilder = ImmutableSet.builder(); |
| for (String classToSkip : classesToSkip) { |
| if (parent == null || !parent.shouldBeSkipped(classToSkip)) { |
| classNamesToSkipBuilder.add(classToSkip); |
| } |
| } |
| this.classNamesToSkip = classNamesToSkipBuilder.build(); |
| } |
| |
| /** Returns a new instance that also skips {@code moreClassesToSkip}. */ |
| public SourceProvider plusSkippedClasses(Class... moreClassesToSkip) { |
| return new SourceProvider(this, asStrings(moreClassesToSkip)); |
| } |
| |
| /** Returns true if the className should be skipped. */ |
| private boolean shouldBeSkipped(String className) { |
| if ((parent != null && parent.shouldBeSkipped(className)) |
| || classNamesToSkip.contains(className)) { |
| return true; |
| } |
| return false; |
| } |
| |
| /** Returns the class names as Strings */ |
| private static List<String> asStrings(Class... classes) { |
| List<String> strings = Lists.newArrayList(); |
| for (Class c : classes) { |
| strings.add(c.getName()); |
| } |
| return strings; |
| } |
| |
| /** |
| * Returns the calling line of code. The selected line is the nearest to the top of the stack that |
| * is not skipped. |
| */ |
| public StackTraceElement get() { |
| for (final StackTraceElement element : new Throwable().getStackTrace()) { |
| String className = element.getClassName(); |
| |
| if (!shouldBeSkipped(className)) { |
| return element; |
| } |
| } |
| throw new AssertionError(); |
| } |
| } |