/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.tomcat.util.scan;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.jar.JarEntry;
import java.util.jar.Manifest;
import org.apache.tomcat.Jar;
/**
* Base implementation of Jar for implementations that use a JarInputStream to access the JAR file.
*/
public abstract class AbstractInputStreamJar implements Jar {
private final URL jarFileURL;
private NonClosingJarInputStream jarInputStream = null;
private JarEntry entry = null;
private Boolean multiRelease = null;
private Map<String,String> mrMap = null;
public AbstractInputStreamJar(URL jarFileUrl) {
this.jarFileURL = jarFileUrl;
}
@Override
public URL getJarFileURL() {
return jarFileURL;
}
@Override
public void nextEntry() {
if (jarInputStream == null) {
try {
reset();
} catch (IOException ioe) {
entry = null;
return;
}
}
try {
entry = jarInputStream.getNextJarEntry();
if (multiRelease.booleanValue()) {
// Skip base entries where there is a multi-release entry
// Skip multi-release entries that are not being used
while (entry != null && (mrMap.containsKey(entry.getName()) ||
entry.getName().startsWith("META-INF/versions/") && !mrMap.containsValue(entry.getName()))) {
entry = jarInputStream.getNextJarEntry();
}
} else {
// Skip multi-release entries
while (entry != null && entry.getName().startsWith("META-INF/versions/")) {
entry = jarInputStream.getNextJarEntry();
}
}
} catch (IOException ioe) {
entry = null;
}
}
@Override
public String getEntryName() {
// Given how the entry name is used, there is no requirement to convert
// the name for a multi-release entry to the corresponding base name.
if (entry == null) {
return null;
} else {
return entry.getName();
}
}
@Override
public InputStream getEntryInputStream() throws IOException {
return jarInputStream;
}
@Override
public InputStream getInputStream(String name) throws IOException {
gotoEntry(name);
if (entry == null) {
return null;
} else {
// Clear the entry so that multiple calls to this method for the
// same entry will result in a new InputStream for each call
// (BZ 60798)
entry = null;
return jarInputStream;
}
}
@Override
public long getLastModified(String name) throws IOException {
gotoEntry(name);
if (entry == null) {
return -1;
} else {
return entry.getTime();
}
}
@Override
public boolean exists(String name) throws IOException {
gotoEntry(name);
return entry != null;
}
@Override
public String getURL(String entry) {
return "jar:" + getJarFileURL().toExternalForm() + "!/" + entry;
}
@Override
public Manifest getManifest() throws IOException {
reset();
return jarInputStream.getManifest();
}
@Override
public void reset() throws IOException {
closeStream();
entry = null;
jarInputStream = createJarInputStream();
// Only perform multi-release processing on first access
if (multiRelease == null) {
Manifest manifest = jarInputStream.getManifest();
if (manifest == null) {
multiRelease = Boolean.FALSE;
} else {
String mrValue = manifest.getMainAttributes().getValue("Multi-Release");
if (mrValue == null) {
multiRelease = Boolean.FALSE;
} else {
multiRelease = Boolean.valueOf(mrValue);
}
}
if (multiRelease.booleanValue()) {
if (mrMap == null) {
populateMrMap();
}
}
}
}
protected void closeStream() {
if (jarInputStream != null) {
try {
jarInputStream.reallyClose();
} catch (IOException ioe) {
// Ignore
}
}
}
protected abstract NonClosingJarInputStream createJarInputStream() throws IOException;
private void gotoEntry(String name) throws IOException {
boolean needsReset = true;
if (multiRelease == null) {
reset();
needsReset = false;
}
// Need to convert requested name to multi-release name (if one exists)
if (multiRelease.booleanValue()) {
String mrName = mrMap.get(name);
if (mrName != null) {
name = mrName;
}
} else if (name.startsWith("META-INF/versions/")) {
entry = null;
return;
}
if (entry != null && name.equals(entry.getName())) {
return;
}
if (needsReset) {
reset();
}
JarEntry jarEntry = jarInputStream.getNextJarEntry();
while (jarEntry != null) {
if (name.equals(jarEntry.getName())) {
entry = jarEntry;
break;
}
jarEntry = jarInputStream.getNextJarEntry();
}
}
private void populateMrMap() throws IOException {
int targetVersion = Runtime.version().feature();
Map<String,Integer> mrVersions = new HashMap<>();
JarEntry jarEntry = jarInputStream.getNextJarEntry();
// Tracking the base name and the latest valid version found is
// sufficient to be able to create the renaming map required
while (jarEntry != null) {
String name = jarEntry.getName();
if (name.startsWith("META-INF/versions/") && name.endsWith(".class")) {
// Get the base name and version for this versioned entry
int i = name.indexOf('/', 18);
if (i > 0) {
String baseName = name.substring(i + 1);
int version = Integer.parseInt(name.substring(18, i));
// Ignore any entries targeting for a later version than
// the target for this runtime
if (version <= targetVersion) {
Integer mappedVersion = mrVersions.get(baseName);
if (mappedVersion == null) {
// No version found for this name. Create one.
mrVersions.put(baseName, Integer.valueOf(version));
} else {
// Ignore any entry for which we have already found
// a later version
if (version > mappedVersion.intValue()) {
// Replace the earlier version
mrVersions.put(baseName, Integer.valueOf(version));
}
}
}
}
}
jarEntry = jarInputStream.getNextJarEntry();
}
mrMap = new HashMap<>();
for (Entry<String,Integer> mrVersion : mrVersions.entrySet()) {
mrMap.put(mrVersion.getKey(),
"META-INF/versions/" + mrVersion.getValue().toString() + "/" + mrVersion.getKey());
}
// Reset stream back to the beginning of the JAR
closeStream();
jarInputStream = createJarInputStream();
}
}