InputStream与String,Byte之间互转

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class InputStreamConvert {

	private final static int BUFFER_SIZE = 4096;

	/**
	 * 将InputStream转换成某种字符编码的String
	 * 
	 * @param in
	 * @param encoding
	 * @return
	 * @throws Exception
	 */
	public static String inputStreamToString(InputStream in, String encoding) throws Exception {

		ByteArrayOutputStream outStream = new ByteArrayOutputStream();
		byte[] data = new byte[BUFFER_SIZE];
		int count = -1;
		while ((count = in.read(data, 0, BUFFER_SIZE)) != -1){
			outStream.write(data, 0, count);
		}

		data = null;
		return new String(outStream.toByteArray(), encoding);
	}

	/**
	 * 将String转换成InputStream
	 * 
	 * @param in
	 * @param encoding
	 * @return
	 * @throws Exception
	 */
	public static InputStream stringToInputStream(String in, String encoding) throws Exception {

		ByteArrayInputStream is = new ByteArrayInputStream(in.getBytes(encoding));
		return is;
	}

	/**
	 * 将InputStream转换成byte数组
	 * 
	 * @param in InputStream
	 * @return byte[]
	 * @throws IOException
	 */
	public static byte[] inputStreamToByte(InputStream in) throws IOException {

		ByteArrayOutputStream outStream = new ByteArrayOutputStream();
		byte[] data = new byte[BUFFER_SIZE];
		int count = -1;
		while ((count = in.read(data, 0, BUFFER_SIZE)) != -1){
			outStream.write(data, 0, count);
		}

		data = null;
		return outStream.toByteArray();
	}

	/**
	 * 将byte数组转换成InputStream
	 * 
	 * @param in
	 * @return
	 * @throws Exception
	 */
	public static InputStream byteToInputStream(byte[] in) throws Exception {

		ByteArrayInputStream is = new ByteArrayInputStream(in);
		return is;
	}

	/**
	 * 将byte数组转换成String
	 * 
	 * @param in
	 * @return
	 * @throws Exception
	 */
	public static String byteToString(byte[] in) throws Exception {

		InputStream is = byteToInputStream(in);
		return inputStreamToString(is,"UTF-8");
	}

}