今天學習的內容是位元組流和位元組流緩衝區

位元組流與字元流的基本操作相同，注意位元組流的輸出沒有用到緩衝區，下例使用FileOutputStream類和FileInputStream類實現對文字檔案的讀寫（位元組流不能直接處理字元內容，只能直接處理位元組內容）：

public class Test78 {

	public static void main(String[] args) {

		test_write();
		test_read_1();
		test_read_2();
	}

	private static void test_read_2() {
		FileInputStream fis = null;
		try {
			fis = new FileInputStream("test.txt");
			byte[] buf = new byte[1024];
			int len = 0;
			while ((len = fis.read(buf)) != -1) {
				System.out.print(new String(buf, 0, len));
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}

	private static void test_read_1() {
		FileInputStream fis = null;
		try {
			fis = new FileInputStream("test.txt");
			int ch = 0;
			while ((ch = fis.read()) != -1) {
				System.out.print((char) ch);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}

	private static void test_write() {
		FileOutputStream fos = null;
		try {
			fos = new FileOutputStream("test.txt");
			fos.write("asdasd".getBytes());// 位元組流操作的是位元組
			// 注意與字元流不同，位元組流並沒有用到緩衝區，不用flush()
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fos != null) {
				try {
					fos.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}
}
 

public class Test79 {

	public static void main(String[] args) {

		copy_picture_1();
		copy_picture_2();
		copy_mp3_1();
		copy_mp3_2();
	}

	private static void copy_mp3_2() {

		BufferedInputStream in = null;
		BufferedOutputStream out = null;
		try {
			in = new BufferedInputStream(new FileInputStream("蕭敬騰 - Beautiful Love.mp3"));
			out = new BufferedOutputStream(new FileOutputStream("蕭敬騰 - Beautiful Love_copy_2.mp3"));
			byte[] buf = new byte[1024];
			int len = 0;
			while ((len = in.read(buf)) != -1) {
				out.write(buf, 0, len);
				out.flush();
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}

	private static void copy_mp3_1() {

		FileInputStream fis = null;
		FileOutputStream fos = null;
		try {
			fis = new FileInputStream("蕭敬騰 - Beautiful Love.mp3");
			fos = new FileOutputStream("蕭敬騰 - Beautiful Love_copy_1.mp3");
			byte[] buf = new byte[1024];
			int len = 0;
			while ((len = fis.read(buf)) != -1) {
				fos.write(buf, 0, len);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fos != null) {
				try {
					fos.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}

	private static void copy_picture_2() {

		BufferedInputStream in = null;
		BufferedOutputStream out = null;
		try {
			in = new BufferedInputStream(new FileInputStream("IO.jpg"));
			out = new BufferedOutputStream(new FileOutputStream("IO_copy_2.jpg"));
			byte[] buf = new byte[1024];
			int len = 0;
			while ((len = in.read(buf)) != -1) {
				out.write(buf, 0, len);
				out.flush();
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}

	private static void copy_picture_1() {

		FileInputStream fis = null;
		FileOutputStream fos = null;
		try {
			fis = new FileInputStream("IO.jpg");
			fos = new FileOutputStream("IO_copy_1.jpg");
			byte[] buf = new byte[1024];
			int len = 0;
			while ((len = fis.read(buf)) != -1) {
				fos.write(buf, 0, len);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fos != null) {
				try {
					fos.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					throw new RuntimeException("關閉資源失敗");
				}
			}
		}
	}
}