Get the specified resource as an input stream. - Java java.util

Java examples for java.util:ResourceBundle

Description

Get the specified resource as an input stream.

Demo Code

/*/*from  w w  w . j  a  va  2 s. com*/
 * JBoss, Home of Professional Open Source
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. 
 * See the copyright.txt in the distribution for a full listing 
 * of individual contributors.
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU Lesser General Public License, v. 2.1.
 * This program is distributed in the hope that it will be useful, but WITHOUT A
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
 * You should have received a copy of the GNU Lesser General Public License,
 * v.2.1 along with this distribution; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301, USA.
 * 
 * (C) 2005-2006,
 * @author JBoss Inc.
 */
//package com.java2s;
import java.io.IOException;
import java.io.InputStream;

import java.net.URL;

public class Main {
    public static void main(String[] argv) throws Exception {
        Class caller = String.class;
        String resource = "java2s.com";
        System.out.println(getResourceAsStream(caller, resource));
    }

    /**
     * Get the specified resource as an input stream.
     * @param caller The caller's class.
     * @param resource The resource name.
     * @return The input stream or null if not found.
     */
    public static InputStream getResourceAsStream(final Class caller,
            final String resource) {
        if ((resource == null) || (resource.length() == 0)) {
            return null;
        }

        final String absoluteResource;
        if (resource.charAt(0) == '/') {
            absoluteResource = resource;
        } else {
            final String callerName = caller.getName();
            final int lastSeparator = callerName.lastIndexOf('.');
            if (lastSeparator == -1) {
                absoluteResource = '/' + resource;
            } else {
                absoluteResource = '/'
                        + callerName.substring(0, lastSeparator + 1)
                                .replace('.', '/') + resource;
            }
        }
        final URL url = getResourceAsURL(caller, absoluteResource);
        if (url != null) {
            try {
                return url.openStream();
            } catch (final IOException ioe) {
            }
        }
        return null;
    }

    /**
     * Get the specified resource as a URL.
     * @param caller The caller's class.
     * @param resource The resource name.
     * @return The URL or null if not found.
     */
    public static URL getResourceAsURL(final Class caller,
            final String resource) {
        final ClassLoader contextClassLoader = Thread.currentThread()
                .getContextClassLoader();
        if (contextClassLoader != null) {
            final URL contextURL = contextClassLoader.getResource(resource);
            if (contextURL != null) {
                return contextURL;
            }
        }
        final URL callerURL = caller.getResource(resource);
        if (callerURL != null) {
            return callerURL;
        }
        return ClassLoader.getSystemResource(resource);
    }
}

Related Tutorials