org.directwebremoting.servlet.FileJavaScriptHandler Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of dwr Show documentation

DWR is easy Ajax for Java. It makes it simple to call Java code directly from Javascript. It gets rid of almost all the boilerplate code between the web browser and your Java code. This version 4.0.2 works with Jakarta Servlet 4.0.2.

There is a newer version: 5.0.0

Show newest version

package org.directwebremoting.servlet;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
import java.net.URL;

import org.directwebremoting.util.CopyUtils;
import org.directwebremoting.util.LocalUtil;

/**
 * Many {@link JavaScriptHandler}s just read their contents from a file. This
 * class simplifies that.
 * @author Joe Walker [joe at getahead dot ltd dot uk]
 * @author Randy Jones (Updates)
 */
public class FileJavaScriptHandler extends JavaScriptHandler
{
    /**
     * @param resource The name of the resource in the classpath that we read
     * our contents from
     */
    public FileJavaScriptHandler(String resource)
    {
        this.resource = resource;
        this.copyright = null;
    }

    /**
     * @param resource The name of the resource in the classpath that we read
     * our contents from
     * @param copyright ...
     */
    public FileJavaScriptHandler(String resource, String copyright)
    {
        this.resource = resource;
        this.copyright = copyright;
    }

    /* (non-Javadoc)
     * @see org.directwebremoting.servlet.CachingHandler#generate(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    @Override
    public String generateCachableContent(String contextPath, String servletPath, String pathInfo) throws IOException
    {
        String output = super.generateCachableContent(contextPath, servletPath, pathInfo);

        if( copyright != null ) {
            output = getCopyright() + output;
        }

        return output;
    }

    /* (non-Javadoc)
     * @see org.directwebremoting.servlet.TemplateHandler#generateTemplate(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    @Override
    protected String generateTemplate(String contextPath, String servletPath, String pathInfo) throws IOException
    {
        StringWriter sw = new StringWriter();
        InputStream raw = null;

        try
        {
            raw = LocalUtil.getInternalResourceAsStream(resource);
            if (raw == null)
            {
                throw new IOException("Failed to find resource: " + resource);
            }

            CopyUtils.copy(raw, sw);
        }
        finally
        {
            LocalUtil.close(raw);
        }

        return sw.toString();
    }

    /**
     * Gets the copyright text to be prepended to the response.
     * @return String copyright text
     * @throws IOException ...
     */
    protected String getCopyright() throws IOException
    {
        StringWriter sw = new StringWriter();
        InputStream raw = null;

        if(copyright != null )
        {
            try
            {
                raw = LocalUtil.getInternalResourceAsStream(copyright);
                if (raw == null)
                {
                    throw new IOException("Failed to find resource: " + copyright);
                }

                CopyUtils.copy(raw, sw);
            }
            finally
            {
                LocalUtil.close(raw);
            }
        }
        return sw.toString();
    }

    /* (non-Javadoc)
     * @see org.directwebremoting.servlet.CachingHandler#getLastModifiedTime()
     */
    @Override
    protected long getLastModifiedTime()
    {
        URL url = FileJavaScriptHandler.class.getResource(LocalUtil.remappedResourcePath(resource));
        if ("file".equals(url.getProtocol()))
        {
            File file = new File(url.getFile());
            return file.lastModified();
        }

        return LocalUtil.getSystemClassloadTime();
    }

    /**
     * The name of the resource in the classpath that we read our contents from
     */
    private final String resource;

    /**
     * The name of the copyright file in the classpath that we read our contents from
     */
    private final String copyright;
}