IOUtils.java

IOUtils.java

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FileOutputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.GZIPInputStream;

public class IOUtils {
	static final Logger logger = Logger.getLogger(IOUtils.class);
	
	static final int BUFFER_SIZE = 512;
	
	/**
	 * Read the content of the resource (from classpath) and return as string
	 * @param resource
	 * @throws IOException
	 */
	public static String getResourceAsString(String resource) throws IOException {
		return fgets(IOUtils.class.getResourceAsStream(resource));		
	}
	
	/**
	 * Read the content of the given input stream into a string
	 */
	public static String fgets(InputStream in) throws IOException {
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		copy(in, out);
		return out.toString();
	}
	
	/**
	 * Read the content of the given file into a string
	 */
	public static String fgets(String fileName) throws IOException {
		FileInputStream in = new FileInputStream(fileName);
		try {
			return fgets(in);
		} finally {
			in.close();
		}
	}


	/**
	 * Write the given data string to the output stream.
	 * @param out
	 * @param data
	 * @throws IOException
	 */
	public static void fputs(OutputStream out, String data) throws IOException {
		ByteArrayInputStream in = new ByteArrayInputStream(data.getBytes());
		copy(in, out);
	}
	
	/**
	 * Save the given data string as file
	 * @param fileName name of the dest file
	 * @param data the data to write
	 */
	public static void fputs(String fileName, String data) throws IOException {
		FileOutputStream out = new FileOutputStream(fileName);
		try {
			fputs(out, data);
		} finally {
			out.close();
		}
	}
	
	/**
	 * Copy the content of one stream to another.  Both streams are not closed
	 * so it's the responsibility of the caller.
	 */
	public static void copy(InputStream in, OutputStream out) throws IOException {
		byte[] bytes = new byte[BUFFER_SIZE];
		for (int bytesRead; (bytesRead = in.read(bytes)) > 0;) {
			out.write(bytes, 0, bytesRead);
		}
         }

	/**
	 * Close the given stream and swallowed all exceptions.
	 */
	public static void close(OutputStream output) {
		if (output != null) {
			try {
				output.close();
			} catch (IOException ex) {
				logger.error("Unable to close output stream", ex);
			}
		}
	}

	/**
	 * Close the given stream and swallowed all exceptions.
	 */
	public static void close(InputStream input) {
		if (input != null) {
			try {
				input.close();
			} catch (IOException ex) {
				logger.error("Unable to close input stream", ex);
			}
		}
	}
}