I/O流

有很多重要的知识点，例如字节流里的InputStream ，OutputStream，字符流里的Reader,Writer这只是主要的两个题目，里面延伸的也有很多知识点

例如InputStream ，OutputStream里的会有FileInputStream,FileOutputStream;ByteArraryInputStream,ByteOutputStreamd;等许多知识点

public class ByteArrayInputSteamDemo {
    public static void main(String[] args) throws IOException {
        String str = "www.baidu.com 百度";
        byte []buffer = str.getBytes();
        ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(buffer);
        int length = 0;
        //缓存区
        byte []buffer1 = new byte[1024];
        while((length = byteArrayInputStream.read(buffer1))!=-1){
            System.out.println(new String (buffer1,0,length));
        }
        try {
            byteArrayInputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }


}

ByteArrayOutputStream

public class ByteArrayOutputSteamDemo {
    public static void main(String[] args) {
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byteArrayOutputStream.write(58);
       byteArrayOutputStream.write("12345".getBytes(),1,3);
        try {
            byteArrayOutputStream.write("www.baidu 百度".getBytes());
            System.out.println(byteArrayOutputStream.toString());
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            try {
                byteArrayOutputStream.close();
            } catch (IOException e) {

            }
        }
    }
}

ObjectInputStream

public class ObjectInputStreamDemo {
    public static void main(String[] args) {
        FileInputStream fileInputStream = null;
        ObjectInputStream objectInputStream = null;

        try {
            fileInputStream = new FileInputStream("a.txt");
            objectInputStream = new ObjectInputStream(fileInputStream);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

ObjectOutputStream

public class ObjectOutputStreamDemo {
    public static void main(String[] args) {
        FileOutputStream fileOutputStream = null;
        ObjectOutputStream objectOutputStream = null;
        try {
            fileOutputStream = new FileOutputStream("a.txt");
            objectOutputStream = new ObjectOutputStream(fileOutputStream);
            objectOutputStream.write("www.cz.com".getBytes());
            objectOutputStream.flush();
            objectOutputStream.writeUTF("wwww.sdsdvsv.com.呵呵");
            objectOutputStream.flush();
            objectOutputStream.writeObject(new person("凉诀城",18,520));
            objectOutputStream.flush();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            try {
                objectOutputStream.close();
                fileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

InputStreamReader

public class InputStreamReaderDemo {
    public static void main(String[] args) throws IOException {
        FileInputStream fileInputStream = null;
        Reader reader= null;
        try {
            fileInputStream = new FileInputStream("b2.txt");
            reader = new InputStreamReader(fileInputStream,"gbk");
            int length = 2;
            char[]chars = new char[1024];
            while((length = reader.read(chars))!=-1){

            }


        } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }


    }
}

OutputStreamWriter

public class OutputStreamWriterDemo {
    public static void main(String[] args) {
        FileOutputStream fileOutputStream = null;
        OutputStreamWriter outputStreamWriter = null;
        try {
            fileOutputStream = new FileOutputStream("a2.txt");
            outputStreamWriter = new OutputStreamWriter(fileOutputStream);

            outputStreamWriter.write(520);
            outputStreamWriter.write("qiamwei");
            outputStreamWriter.write(250);


        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }  catch (IOException e) {
        e.printStackTrace();
        }finally {
            try {
                outputStreamWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                fileOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }
}

InputStream?

public class InputStreamDemo {
    public static void main(String[] args) {
      InputStream inputStream = null;
        try {
            //创建流对象
            inputStream = new FileInputStream("a1.txt");
            //传输数据
            int read = inputStream.read();
            System.out.println((char)read);
            read = inputStream.read();
            System.out.println((char)read);
            read = inputStream.read();
            System.out.println((char)read);
            read = inputStream.read();
            System.out.println((char)read);
            read = inputStream.read();
            System.out.println((char)read);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

?OutputStream

public class OutputStreamDemo {
    public static void main(String[] args) {
        File file = new File("a2.txt");
        OutputStream outputStream = null;
        try {
            //创建流对象
            outputStream = new FileOutputStream(file,true);
            //传输数据
            outputStream.write(98);
            outputStream.write("www.baidu.com百度".getBytes());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //关闭流对象
            try {
                outputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

CharArrayRead

public class CharArrayReadDemo {
    public static void main(String[] args) {
        String str = "www.baidu.com百度";
        char[] chars = str.toCharArray();
        CharArrayReader charArrayReader = new CharArrayReader(chars);
        int length = 0;
        char[] buffer = new char[1024];
            try {
                while (!((length = charArrayReader.read(buffer)) != -1)) break;
                //    System.out.println(new String (chars,0,length));
                System.out.println(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                charArrayReader.close();
            }
        }
}

CharArraryWrite

public class CharArrayWriteDemo {
    public static void main(String[] args) {
        CharArrayWriter charArrayWriter = null;
        try {
            charArrayWriter =new CharArrayWriter();
            charArrayWriter.write(100);
            charArrayWriter.write("www.alibaba");
            charArrayWriter.append("A").append("s");
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            charArrayWriter.close();
        }
    }
}

当然I/O流里的知识不止这些，我只是简单的例举了几个而已。