org.eclipse.jst.server.jetty.core/src/org/eclipse/jst/server/jetty/core/internal/util/IOUtils.java

/*******************************************************************************
 * Copyright (c) 2010 Angelo Zerr and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Angelo Zerr <angelo.zerr@gmail.com> - Initial API and implementation 
 *******************************************************************************/
package org.eclipse.jst.server.jetty.core.internal.util;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;

import org.eclipse.core.filesystem.EFS;
import org.eclipse.core.filesystem.IFileStore;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IWorkspaceRoot;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;

/**
 * I/O Utilities.
 * 
 */
public class IOUtils
{

    private static final int __DEFAULT_BUFFER_SIZE = 1024 * 4;

    /**
     * Converts the given URI to a local file. Use the existing file if the uri is on the local file system. Otherwise fetch it. Returns null if unable to fetch
     * it.
     * 
     * @param uri
     * @param monitor
     * @return
     * @throws CoreException
     */
    public static File toLocalFile(URI uri, IProgressMonitor monitor) throws CoreException
    {
        IFileStore fileStore = EFS.getStore(uri);
        File localFile = fileStore.toLocalFile(EFS.NONE,monitor);
        if (localFile == null)
            // non local file system
            localFile = fileStore.toLocalFile(EFS.CACHE,monitor);
        return localFile;
    }

    public static File toLocalFile(IFile file, IProgressMonitor monitor) throws CoreException
    {
        return toLocalFile(file.getLocationURI(),monitor);
    }

    /**
     * Create Eclipse {@link IFolder}.
     * 
     * @param folderHandle
     * @param monitor
     * @throws CoreException
     */
    public static void createFolder(IFolder folderHandle, IProgressMonitor monitor) throws CoreException
    {
        if (folderHandle.exists())
            return;

        IPath path = folderHandle.getFullPath();
        IWorkspaceRoot root = ResourcesPlugin.getWorkspace().getRoot();
        int numSegments = path.segmentCount();
        if (numSegments > 2 && !root.getFolder(path.removeLastSegments(1)).exists())
        {
            // If the direct parent of the path doesn't exist, try
            // to create the
            // necessary directories.
            for (int i = numSegments - 2; i > 0; i--)
            {
                IFolder folder = root.getFolder(path.removeLastSegments(i));
                if (!folder.exists())
                {
                    folder.create(false,true,monitor);
                }
            }
        }
        folderHandle.create(false,true,monitor);
    }

    public static InputStream getInputStream(File jarFile, String fileName) throws ZipException, IOException
    {
        ZipFile zipFile = new ZipFile(jarFile);
        ZipEntry zipEntry = zipFile.getEntry(fileName);
        return zipFile.getInputStream(zipEntry);
    }

    /**
     * Copy bytes from an <code>InputStream</code> to an <code>OutputStream</code>.
     * 
     * @param input
     *            the <code>InputStream</code> to read from
     * @param output
     *            the <code>OutputStream</code> to write to
     * @return the number of bytes copied
     * @throws IOException
     *             In case of an I/O problem
     */
    public static int copy(InputStream input, OutputStream output) throws IOException
    {
        byte[] buffer = new byte[__DEFAULT_BUFFER_SIZE];
        int count = 0;
        int n = 0;
        while (-1 != (n = input.read(buffer)))
        {
            output.write(buffer,0,n);
            count += n;
        }
        return count;
    }

    public static InputStream toInputStream(String input, String encoding) throws IOException
    {
        byte bytes[] = encoding == null?input.getBytes():input.getBytes(encoding);
        return new ByteArrayInputStream(bytes);
    }
}