private static void io3() {
		DataOutputStream out = null;
		try {
			out = new DataOutputStream(new FileOutputStream(filePath));
			out.write(content.getBytes());
		} catch (FileNotFoundException e) {
			throw new RuntimeException(e);
		} catch (IOException e) {
			throw new RuntimeException(e);
		} finally {
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
		}

		sb.setLength(0);

		DataInputStream in = null;
		try {
			in = new DataInputStream(new FileInputStream(filePath));

			byte[] b = new byte[32];

			int s;

			while ((s = in.read(b)) != -1) {
				sb.append(new String(b, 0, s));
			}

		} catch (FileNotFoundException e) {
			throw new RuntimeException(e);
		} catch (IOException e) {
			throw new RuntimeException(e);
		} finally {
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
		}

		System.out.print(sb.toString());
	}