freemarker.cache.URLTemplateSource Maven / Gradle / Ivy
/*
* 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 freemarker.cache;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.JarURLConnection;
import java.net.URL;
import java.net.URLConnection;
/**
* Wraps a {@link URL}, and implements methods required for a typical template source.
*/
class URLTemplateSource {
private final URL url;
private URLConnection conn;
private InputStream inputStream;
private Boolean useCaches;
/**
* @param useCaches {@code null} if this aspect wasn't set in the parent {@link TemplateLoader}.
*/
URLTemplateSource(URL url, Boolean useCaches) throws IOException {
this.url = url;
this.conn = url.openConnection();
this.useCaches = useCaches;
if (useCaches != null) {
conn.setUseCaches(useCaches.booleanValue());
}
}
@Override
public boolean equals(Object o) {
if (o instanceof URLTemplateSource) {
return url.equals(((URLTemplateSource) o).url);
} else {
return false;
}
}
@Override
public int hashCode() {
return url.hashCode();
}
@Override
public String toString() {
return url.toString();
}
long lastModified() {
if (conn instanceof JarURLConnection) {
// There is a bug in sun's jar url connection that causes file handle leaks when calling getLastModified()
// (see https://bugs.openjdk.java.net/browse/JDK-6956385).
// Since the time stamps of jar file contents can't vary independent from the jar file timestamp, just use
// the jar file timestamp
URL jarURL = ((JarURLConnection) conn).getJarFileURL();
if (jarURL.getProtocol().equals("file")) {
// Return the last modified time of the underlying file - saves some opening and closing
return new File(jarURL.getFile()).lastModified();
} else {
// Use the URL mechanism
URLConnection jarConn = null;
try {
jarConn = jarURL.openConnection();
return jarConn.getLastModified();
} catch (IOException e) {
return -1;
} finally {
try {
if (jarConn != null) jarConn.getInputStream().close();
} catch (IOException e) { }
}
}
} else {
long lastModified = conn.getLastModified();
if (lastModified == -1L && url.getProtocol().equals("file")) {
// Hack for obtaining accurate last modified time for
// URLs that point to the local file system. This is fixed
// in JDK 1.4, but prior JDKs returns -1 for file:// URLs.
return new File(url.getFile()).lastModified();
} else {
return lastModified;
}
}
}
InputStream getInputStream() throws IOException {
if (inputStream != null) {
// Ensure that the returned InputStream reads from the beginning of the resource when getInputStream()
// is called for the second time:
try {
inputStream.close();
} catch (IOException e) {
// Ignore; this is maybe because it was closed for the 2nd time now
}
this.conn = url.openConnection();
}
inputStream = conn.getInputStream();
return inputStream;
}
void close() throws IOException {
try {
if (inputStream != null) {
inputStream.close();
} else {
conn.getInputStream().close();
}
} finally {
inputStream = null;
conn = null;
}
}
Boolean getUseCaches() {
return useCaches;
}
void setUseCaches(boolean useCaches) {
if (this.conn != null) {
conn.setUseCaches(useCaches);
this.useCaches = Boolean.valueOf(useCaches);
}
}
}