Application Integration Filters

package nl.gx.webmanager.servlet.applications;

/**A smple filter that writes the content of a file to the response output stream. This filter may be used to
test the application integration module and is especially useful to test other filters.
*/

public class IncludeFileFilter implements Filter {

	private String filename;

	public void init(FilterConfig config) throws ServletException {
		// get the filename from the configuration
		filename = config.getInitParameter("filename");
	}

	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {

	// get a writer 
	PrintWriter writer = res.getWriter();

	// create a reader for the file
	FileReader fileReader = new FileReader(new File(filename));
	BufferedReader br = new BufferedReader(fileReader);

	// write the file content
	int charsRead;
	char[] buffer = new char[4096];

	try {
		while ((charsRead = br.read(buffer)) != -1) {
			writer.write(buffer, 0, charsRead);
		}
	} finally {
	// be sure to close the reader properly
		br.close();
	}
	// call the next filter
	chain.doFilter(req, res);
	}

	public void destroy() {
	}
}

package nl.gx.webmanager.handler.servlet.applications;

/**
This filter transforms the XML that is written to the response with XSL that is fetched from the
specified URL. It wraps the response so that the XML that is written to it is transformed on the fly.
The XSL can come from a URL, a file or a resource (obtained using the classloader).
*/

public class XSLFilter implements Filter {

	public void doFilter(ServletRequest req, ServletResponse res,FilterChain chain) throws IOException, ServletException {
		// wrap the response and let other filters/servlets write the XML that needs to be transformed
		CharResponseWrapper responseWrapper = new CharResponseWrapper((HttpServletResponse)res, servletContext);
		chain.doFilter(req,responseWrapper);

		// get input reader for the XSL 
		Reader r;
		if(xslUrl != null) {
		// download the XSL
			r = getXslFromUrl(xslUrl);
		} else if(xslResource != null){
			// get the XSL as a resource from the classpath
			r = new InputStreamReader(getClass().getClassLoader().getResourceAsStream(xslResource));
		} else if(xslFile != null) {
			// get the XSL from a file
			r = new FileReader(xslFile);
		}

		// read the stylesheet into a String
		try {
			String line;
			while((line = br.readLine()) != null) {
				pw.println(line);
			}
		} finally {
			// always clean up
			try { br.close(); }
			finally { pw.close(); }
		}
		String stylesheet = sw.getBuffer().toString();
		LOG.finest(stylesheet);

		// use the wrapped response as input
		StringReader xmlReader = new StringReader(responseWrapper.toString());

		// transform using the XSL transformer pool from XMLUtil.
		try {
			XMLUtil.transform(stylesheet, xmlReader, res.getWriter());
		}

	}
	Private Reader getXslFromUrl(String url) throws IOException, HttpException {
		// get the XSL from the URL
		HttpClient client = new HttpClient();
		GetMethod get = new GetMethod(url);
		client.executeMethod(get);
		int statusCode = get.getStatusCode();
		InputStream is = get.getResponseBodyAsStream();
		return new InputStreamReader(is, get.getResponseCharSet());
	}

	public void destroy() {
		LOG.info("XSLFilter destroyed");
	}
}

package nl.yoursite.filters;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class HelloWorldFilter implements Filter {
	private String message;
    public void init(FilterConfig config) throws ServletException {
		// Get the message from the configuration:
		message = config.getInitParameter("message");
	}

	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
	// Write something to the output stream:
	res.getWriter().print(message);
	// Call the next filter:
	chain.doFilter(req,res);
	}
	public void destroy() {
	}
}

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<artifactId>XperienCentral-libraries</artifactId>
		<groupId>nl.gx.webmanager.libraries</groupId>
		<version>10.11.0</version>
	</parent>
	<artifactId>project-applicationintegrationfilters</artifactId>
	<version>1.0.0</version>
	<name>project-applicationintegrationfilters</name>
	<description>
		Project-specific filters for application integration
	</description>
	<url>www.yoursite.com</url>
	<build>
		<defaultGoal>package</defaultGoal>
	</build>

	<dependencies>
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>servlet</artifactId>
			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>jsp-api</artifactId>
			<version>2.0</version>
			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>nl.gx.webmanager.libraries</groupId>
			<artifactId>XperienCentral-api</artifactId>
			<version>${pom.parent.version}</version>
			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>nl.gx.webmanager.libraries</groupId>
			<artifactId>XperienCentral-apiimpl</artifactId>
			<version>${pom.parent.version}</version>
			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>nl.gx.webmanager.libraries</groupId>
			<artifactId>XperienCentral-handler</artifactId>
			<version>${pom.parent.version}</version>
			<scope>provided</scope>
		</dependency>
	</dependencies>
</project>