IOUtil.java

package edu.berkeley.nlp.util;

import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class IOUtil
{
	
	 public static File createTempDirectory(String prefix)
     throws IOException
     {
         File tempFile = File.createTempFile(prefix, "");
         if (!tempFile.delete())
             throw new IOException();
         if (!tempFile.mkdir())
             throw new IOException();
         return tempFile;        
     }

	/**
	 *
	 * @param dir
	 * @param filePrefix
	 * @param fileExt
	 * @param recursive
	 * @return
	 */
	public static List<File> getFilesUnder(
				final String dir, // Directory
	      final String filePrefix, // Prefix for files
	      final String fileExt,    // Extension of files
	      final boolean recursive) {
			List<File> files = new ArrayList<File>();
			File dirFile = new File(dir);
      if (!dirFile.exists()) return files;
      if (!dirFile.isDirectory()) return Collections.singletonList(dirFile);
			for (File f: dirFile.listFiles()) {
				if (f.isDirectory()) {
					if (recursive) files.addAll(getFilesUnder(f.getAbsolutePath(),filePrefix,fileExt,recursive));
					continue;
				}
				String name = f.getName();
				if (name.startsWith(filePrefix) && name.endsWith(fileExt)) {
					files.add(f);
				}
			}
      return files;
	}

	public static FileFilter getFileFilter(final String prefix, final String ext) 
	{
		return new FileFilter() {
			public boolean accept(File pathname) {
				// TODO Auto-generated method stub
				String name = pathname.getName();
				return name.startsWith(prefix) && name.endsWith(ext);
			}			
		};
	}

	 
	 public static boolean deleteDir(File dir)
	{
		if (dir.isDirectory())
		{
			String[] children = dir.list();
			for (int i = 0; i < children.length; i++)
			{
				boolean success = deleteDir(new File(dir, children[i]));
				if (!success) { return false; }
			}
		}

		// The directory is now empty so delete it
		return dir.delete();
	}

  public static FileReader fileReaderHard(String filename) {
    try {
      return new FileReader(filename);
    } catch (FileNotFoundException e) {
      e.printStackTrace();
      System.exit(0);
    }
    throw new IllegalStateException();
  }

  public static String getPath(String parentPath, String childName) {
    return new File(parentPath,childName).getPath();
  }
}