com.google.inject.internal.util.StackTraceElements 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 com.google.inject.internal.util;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Member;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* Creates stack trace elements for members.
*
* @author [email protected] (Bob Lee)
*/
public final class StackTraceElements {
private static final StackTraceElement[] EMPTY_STACK_TRACE = new StackTraceElement[0];
private static final InMemoryStackTraceElement[] EMPTY_INMEMORY_STACK_TRACE =
new InMemoryStackTraceElement[0];
static final LoadingCache, LineNumbers> lineNumbersCache =
CacheBuilder.newBuilder()
.weakKeys()
.softValues()
.build(
new CacheLoader, LineNumbers>() {
@Override
public LineNumbers load(Class key) {
try {
return new LineNumbers(key);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
});
private static final ConcurrentMap
elementCache = new ConcurrentHashMap<>();
private static final ConcurrentMap stringCache = new ConcurrentHashMap<>();
private static final String UNKNOWN_SOURCE = "Unknown Source";
public static Object forMember(Member member) {
if (member == null) {
return SourceProvider.UNKNOWN_SOURCE;
}
Class declaringClass = member.getDeclaringClass();
LineNumbers lineNumbers = lineNumbersCache.getUnchecked(declaringClass);
String fileName = lineNumbers.getSource();
Integer lineNumberOrNull = lineNumbers.getLineNumber(member);
int lineNumber = lineNumberOrNull == null ? lineNumbers.getFirstLine() : lineNumberOrNull;
Class memberType = Classes.memberType(member);
String memberName = memberType == Constructor.class ? "" : member.getName();
return new StackTraceElement(declaringClass.getName(), memberName, fileName, lineNumber);
}
public static Object forType(Class implementation) {
LineNumbers lineNumbers = lineNumbersCache.getUnchecked(implementation);
int lineNumber = lineNumbers.getFirstLine();
String fileName = lineNumbers.getSource();
return new StackTraceElement(implementation.getName(), "class", fileName, lineNumber);
}
/** Clears the internal cache for {@link StackTraceElement StackTraceElements}. */
public static void clearCache() {
elementCache.clear();
stringCache.clear();
}
/** Returns encoded in-memory version of {@link StackTraceElement StackTraceElements}. */
public static InMemoryStackTraceElement[] convertToInMemoryStackTraceElement(
StackTraceElement[] stackTraceElements) {
if (stackTraceElements.length == 0) {
return EMPTY_INMEMORY_STACK_TRACE;
}
InMemoryStackTraceElement[] inMemoryStackTraceElements =
new InMemoryStackTraceElement[stackTraceElements.length];
for (int i = 0; i < stackTraceElements.length; i++) {
inMemoryStackTraceElements[i] =
weakIntern(new InMemoryStackTraceElement(stackTraceElements[i]));
}
return inMemoryStackTraceElements;
}
/**
* Decodes in-memory stack trace elements to regular {@link StackTraceElement StackTraceElements}.
*/
public static StackTraceElement[] convertToStackTraceElement(
InMemoryStackTraceElement[] inMemoryStackTraceElements) {
if (inMemoryStackTraceElements.length == 0) {
return EMPTY_STACK_TRACE;
}
StackTraceElement[] stackTraceElements =
new StackTraceElement[inMemoryStackTraceElements.length];
for (int i = 0; i < inMemoryStackTraceElements.length; i++) {
String declaringClass = inMemoryStackTraceElements[i].getClassName();
String methodName = inMemoryStackTraceElements[i].getMethodName();
int lineNumber = inMemoryStackTraceElements[i].getLineNumber();
stackTraceElements[i] =
new StackTraceElement(declaringClass, methodName, UNKNOWN_SOURCE, lineNumber);
}
return stackTraceElements;
}
private static InMemoryStackTraceElement weakIntern(
InMemoryStackTraceElement inMemoryStackTraceElement) {
InMemoryStackTraceElement cached = elementCache.get(inMemoryStackTraceElement);
if (cached != null) {
return cached;
}
inMemoryStackTraceElement =
new InMemoryStackTraceElement(
weakIntern(inMemoryStackTraceElement.getClassName()),
weakIntern(inMemoryStackTraceElement.getMethodName()),
inMemoryStackTraceElement.getLineNumber());
elementCache.put(inMemoryStackTraceElement, inMemoryStackTraceElement);
return inMemoryStackTraceElement;
}
private static String weakIntern(String s) {
String cached = stringCache.get(s);
if (cached != null) {
return cached;
}
stringCache.put(s, s);
return s;
}
/** In-Memory version of {@link StackTraceElement} that does not store the file name. */
public static class InMemoryStackTraceElement {
private final String declaringClass;
private final String methodName;
private final int lineNumber;
InMemoryStackTraceElement(StackTraceElement ste) {
this(ste.getClassName(), ste.getMethodName(), ste.getLineNumber());
}
InMemoryStackTraceElement(String declaringClass, String methodName, int lineNumber) {
this.declaringClass = declaringClass;
this.methodName = methodName;
this.lineNumber = lineNumber;
}
String getClassName() {
return declaringClass;
}
String getMethodName() {
return methodName;
}
int getLineNumber() {
return lineNumber;
}
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof InMemoryStackTraceElement)) {
return false;
}
InMemoryStackTraceElement e = (InMemoryStackTraceElement) obj;
return e.declaringClass.equals(declaringClass)
&& e.lineNumber == lineNumber
&& methodName.equals(e.methodName);
}
@Override
public int hashCode() {
int result = 31 * declaringClass.hashCode() + methodName.hashCode();
result = 31 * result + lineNumber;
return result;
}
@Override
public String toString() {
return declaringClass + "." + methodName + "(" + lineNumber + ")";
}
}
private StackTraceElements() {}
}