JspFactoryImpl.java
/*
* 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.jasper.runtime;
import java.io.IOException;
import jakarta.servlet.Servlet;
import jakarta.servlet.ServletContext;
import jakarta.servlet.ServletRequest;
import jakarta.servlet.ServletResponse;
import jakarta.servlet.jsp.JspApplicationContext;
import jakarta.servlet.jsp.JspEngineInfo;
import jakarta.servlet.jsp.JspFactory;
import jakarta.servlet.jsp.PageContext;
import org.apache.jasper.Constants;
/**
* Implementation of JspFactory.
*
* @author Anil K. Vijendran
*/
public class JspFactoryImpl extends JspFactory {
private final ThreadLocal<PageContextPool> localPool = new ThreadLocal<>();
private int poolSize = -1;
@Override
public PageContext getPageContext(Servlet servlet, ServletRequest request,
ServletResponse response, String errorPageURL, boolean needsSession,
int bufferSize, boolean autoflush) {
PageContext pc;
if (poolSize > 0) {
PageContextPool pool = localPool.get();
if (pool == null) {
pool = new PageContextPool(poolSize);
localPool.set(pool);
}
pc = pool.get();
if (pc == null) {
pc = new PageContextImpl();
}
} else {
pc = new PageContextImpl();
}
try {
pc.initialize(servlet, request, response, errorPageURL,
needsSession, bufferSize, autoflush);
} catch (IOException ioe) {
// Implementation never throws IOE but can't change the signature
// since it is part of the JSP API
}
return pc;
}
@Override
public void releasePageContext(PageContext pc) {
if( pc == null ) {
return;
}
pc.release();
if (poolSize > 0 && (pc instanceof PageContextImpl)) {
localPool.get().put(pc);
}
}
@Override
public JspEngineInfo getEngineInfo() {
return new JspEngineInfo() {
@Override
public String getSpecificationVersion() {
return Constants.SPEC_VERSION;
}
};
}
public void setPoolSize(int poolSize) {
this.poolSize = poolSize;
}
private static final class PageContextPool {
private final PageContext[] pool;
private int current = -1;
PageContextPool(int poolSize) {
this.pool = new PageContext[poolSize];
}
public void put(PageContext o) {
if (current < (pool.length - 1)) {
current++;
pool[current] = o;
}
}
public PageContext get() {
PageContext item = null;
if (current >= 0) {
item = pool[current];
current--;
}
return item;
}
}
@Override
public JspApplicationContext getJspApplicationContext(
final ServletContext context) {
return JspApplicationContextImpl.getInstance(context);
}
}