org.elasticsearch.common.inject.internal.SourceProvider Maven / Gradle / Ivy
/**
* 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 org.elasticsearch.common.inject.internal;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import java.util.List;
/**
* Provides access to the calling line of code.
*
* @author [email protected] (Bob Lee)
*/
public class SourceProvider {
/**
* Indicates that the source is unknown.
*/
public static final Object UNKNOWN_SOURCE = "[unknown source]";
private final ImmutableSet classNamesToSkip;
public SourceProvider() {
this.classNamesToSkip = ImmutableSet.of(SourceProvider.class.getName());
}
public static final SourceProvider DEFAULT_INSTANCE
= new SourceProvider(ImmutableSet.of(SourceProvider.class.getName()));
private SourceProvider(Iterable classesToSkip) {
this.classNamesToSkip = ImmutableSet.copyOf(classesToSkip);
}
/**
* Returns a new instance that also skips {@code moreClassesToSkip}.
*/
public SourceProvider plusSkippedClasses(Class... moreClassesToSkip) {
return new SourceProvider(Iterables.concat(classNamesToSkip, asStrings(moreClassesToSkip)));
}
/**
* Returns the class names as Strings
*/
private static List asStrings(Class... classes) {
List 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 (!classNamesToSkip.contains(className)) {
return element;
}
}
throw new AssertionError();
}
}