public class StringDemo {
    public static void main(String[] args) throws UnsupportedEncodingException {
        //define a string
        String s = "China";

        //byte[] bys = s.getBytes(); //[-28, -72, -83, -27, -101, -67]
        //byte[] bys = s.getBytes("UTF-8"); //[-28, -72, -83, -27, -101, -67]
        byte[] bys = s.getBytes("GBK"); //[-42, -48, -71, -6]
        System.out.println(Arrays.toString(bys));

        //String ss = new String(bys);
        //String ss = new String(bys,"UTF-8");
        String ss = new String(bys,"GBK");
        System.out.println(ss);
    }
}

public class OutputStreamWriterDemo {
    public static void main(String[] args) throws IOException {
        FileWriter fw = new FileWriter("myCharStream\\a.txt");

        //void write(int c): write a character
//        fw.write(97);
//        fw.write(98);
//        fw.write(99);

        //void write(char[] cbuf): write a character array
        char[] chs = {'a', 'b', 'c', 'd', 'e'};
//        fw.write(chs);

        //void write(char[] cbuf, int off, int len): write part of the character array
//        fw.write(chs, 0, chs.length);
//        fw.write(chs, 1, 3);

        //void write(String str): write a string
//        fw.write("abcde");

        //void write(String str, int off, int len): write part of a string
//        fw.write("abcde", 0, "abcde".length());
        fw.write("abcde", 1, 3);

        //release resources
        fw.close();
    }
}

public class InputStreamReaderDemo {
    public static void main(String[] args) throws IOException {
   
        FileReader fr = new FileReader("myCharStream\\b.txt");

        //int read(): read one character data at a time
//        int ch;
//        while ((ch=fr.read())!=-1) {
//            System.out.print((char)ch);
//        }

        //int read(char[] cbuf): read one character array data at a time
        char[] chs = new char[1024];
        int len;
        while ((len = fr.read(chs)) != -1) {
            System.out.print(new String(chs, 0, len));
        }

        //release resources
        fr.close();
    }
}

public class CharStreamDemo8 {
    public static void main(String[] args) throws IOException {
        //Requirement: Save the user name and password entered by the keyboard to the local for permanent storage
        //Requirements: The username is on one line alone, and the password is on one line alone

        //analyze:
        //1. Realize keyboard entry, enter user name and password
        Scanner sc = new Scanner(System.in);
        System.out.println("Please enter username");
        String username = sc.next();
        System.out.println("Please enter password");
        String password = sc.next();

        //2. Write the user name and password to the local file respectively.
        FileWriter fw = new FileWriter("charstream\\a.txt");
        //Write username and password to a file
        fw.write(username);
        //Indicates writing a carriage return and line feed windows \r\n MacOS \r Linux \n
        fw.write("\r\n");
        fw.write(password);
        //refresh stream
        fw.flush();
        //3. Shutdown, release resources
        fw.close();
    }
}

public class BufferedStreamDemo01 {
    public static void main(String[] args) throws IOException {
        //BufferedWriter(Writer out)
        BufferedWriter bw = new BufferedWriter(new                                                            FileWriter("myCharStream\\bw.txt"));
        bw.write("hello\r\n");
        bw.write("world\r\n");
        bw.close();

        //BufferedReader(Reader in)
        BufferedReader br = new BufferedReader(new                                                           FileReader("myCharStream\\bw.txt"));

        //Read character data one at a time
//        int ch;
//        while ((ch=br.read())!=-1) {
//            System.out.print((char)ch);
//        }

        //Read character array data one at a time
        char[] chs = new char[1024];
        int len;
        while ((len=br.read(chs))!=-1) {
            System.out.print(new String(chs,0,len));
        }

        br.close();
    }
}

public class BufferedStreamDemo02 {
    public static void main(String[] args) throws IOException {

        //Create a character buffered output stream
        BufferedWriter bw = new BufferedWriter(new                                                          FileWriter("myCharStream\\bw.txt"));

        //write data
        for (int i = 0; i < 10; i++) {
            bw.write("hello" + i);
            //bw.write("\r\n");
            bw.newLine();
            bw.flush();
        }

        //release resources
        bw.close();

        //Create a character buffered input stream
        BufferedReader br = new BufferedReader(new                                                          FileReader("myCharStream\\bw.txt"));

        String line;
        while ((line=br.readLine())!=null) {
            System.out.println(line);
        }

        br.close();
    }
}

public class CharStreamDemo14 {
    public static void main(String[] args) throws IOException {
        //Requirement: read the data in the file, write to the local file again after sorting
        //analyze:
        //1. To read the data in the file.
        BufferedReader br = new BufferedReader(new FileReader("charstream\\sort.txt"));
        //The output stream must not be written here, because the contents of the file will be emptied
        //BufferedWriter bw = new BufferedWriter(new FileWriter("charstream\\sort.txt"));

        String line = br.readLine();
        System.out.println("The read data is" + line);
        br.close();

        //2. Cut according to the space
        String[] split = line.split(" ");//9 1 2 5 3 10 4 6 7 8
        //3. Change the array of string type into int type
        int [] arr = new int[split.length];
        //Traversing the split array can perform type conversion.
        for (int i = 0; i < split.length; i++) {
            String smallStr = split[i];
            //type conversion
            int number = Integer.parseInt(smallStr);
            //Store the converted result in arr
            arr[i] = number;
        }
        //4. Sort
        Arrays.sort(arr);
        System.out.println(Arrays.toString(arr));

        //5. Write the sorted results back to the local 1 2 3 4...
        BufferedWriter bw = new BufferedWriter(new FileWriter("charstream\\sort.txt"));
        //write out
        for (int i = 0; i < arr.length; i++) {
            bw.write(arr[i] + " ");
            bw.flush();
        }
        //release resources
        bw.close();

    }
}

public class ConversionStreamDemo {
    public static void main(String[] args) throws IOException {
        //OutputStreamWriter osw = new OutputStreamWriter(new                                             FileOutputStream("myCharStream\\osw.txt"));
        OutputStreamWriter osw = new OutputStreamWriter(new                                              FileOutputStream("myCharStream\\osw.txt"),"GBK");
        osw.write("China");
        osw.close();

        //InputStreamReader isr = new InputStreamReader(new 	                                         FileInputStream("myCharStream\\osw.txt"));
        InputStreamReader isr = new InputStreamReader(new                                                 FileInputStream("myCharStream\\osw.txt"),"GBK");
        //Read character data one at a time
        int ch;
        while ((ch=isr.read())!=-1) {
            System.out.print((char)ch);
        }
        isr.close();
    }
}

public class Student implements Serializable {
    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

public class ObjectOutputStreamDemo {
    public static void main(String[] args) throws IOException {
        //ObjectOutputStream(OutputStream out): Creates an ObjectOutputStream written to the specified OutputStream
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("myOtherStream\\oos.txt"));

        //create object
        Student s = new Student("Tong Liya",30);

        //void writeObject(Object obj): write the specified object to ObjectOutputStream
        oos.writeObject(s);

        //release resources
        oos.close();
    }
}

public class ObjectInputStreamDemo {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        //ObjectInputStream(InputStream in): Creates an ObjectInputStream that reads from the specified InputStream
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("myOtherStream\\oos.txt"));

        //Object readObject(): read an object from ObjectInputStream
        Object obj = ois.readObject();

        Student s = (Student) obj;
        System.out.println(s.getName() + "," + s.getAge());

        ois.close();
    }
}

public class Student implements Serializable {
    private static final long serialVersionUID = 42L;
    private String name;
//    private int age;
    private transient int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

//    @Override
//    public String toString() {
//        return "Student{" +
//                "name='" + name + '\'' +
//                ", age=" + age +
//                '}';
//    }
}

public class ObjectStreamDemo {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
//        write();
        read();
    }

    //deserialization
    private static void read() throws IOException, ClassNotFoundException {
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("myOtherStream\\oos.txt"));
        Object obj = ois.readObject();
        Student s = (Student) obj;
        System.out.println(s.getName() + "," + s.getAge());
        ois.close();
    }

    //Serialization
    private static void write() throws IOException {
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("myOtherStream\\oos.txt"));
        Student s = new Student("Tong Liya", 30);
        oos.writeObject(s);
        oos.close();
    }
}

public class Student implements Serializable{
    
    private static final long serialVersionUID = 2L;

    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

public class Demo03 {
    /**
     *  read():
     *      Read to the end of the file and the return value is -1
     *  readLine():
     *      Read to the end of the file and return the value null
     *  readObject():
     *      Read to the end of the file and throw an exception directly
     *  If there are multiple objects to be serialized, it is not recommended to serialize multiple objects directly into the file, because it is easy to get an exception when deserializing
     *      Suggestion: Store multiple objects to be serialized into a collection, then serialize the collection into a file
     */
    public static void main(String[] args) throws Exception {
        /*// Serialization
        //1.Create a serialized stream object
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("myCode\\oos.txt"));
        ArrayList<Student> arrayList = new ArrayList<>();
        //2.Create multiple student objects
        Student s = new Student("Tong Liya",30);
        Student s01 = new Student("Tong Liya",30);
        //3.Add the student object to the collection
        arrayList.add(s);
        arrayList.add(s01);
        //4.Serialize the collection object to a file
        oos.writeObject(arrayList);
        oos.close();*/

        // deserialization
      	//5. Create a deserialized stream object
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("myCode\\oos.txt"));
      	//6. Read the object data in the file into the memory
        Object obj = ois.readObject();
        ArrayList<Student> arrayList = (ArrayList<Student>)obj;
        ois.close();
        for (Student s : arrayList) {
            System.out.println(s.getName() + "," + s.getAge());
        }
    }
}

public class PropertiesDemo01 {
    public static void main(String[] args) {
        //Create a collection object
//        Properties<String,String> prop = new Properties<String,String>(); //Error
        Properties prop = new Properties();

        //storage element
        prop.put("itheima001", "Tong Liya");
        prop.put("itheima002", "Zhao Liying");
        prop.put("itheima003", "Liu Shishi");

        //iterate through the collection
        Set<Object> keySet = prop.keySet();
        for (Object key : keySet) {
            Object value = prop.get(key);
            System.out.println(key + "," + value);
        }
    }
}

public class PropertiesDemo02 {
    public static void main(String[] args) {
        //Create a collection object
        Properties prop = new Properties();

        //Object setProperty(String key, String value): Set the key and value of the collection, both of String type
        prop.setProperty("itheima001", "Tong Liya");
        prop.setProperty("itheima002", "Zhao Liying");
        prop.setProperty("itheima003", "Liu Shishi");

        //String getProperty(String key): Searches for a property using the key specified in this property list
//        System.out.println(prop.getProperty("itheima001"));
//        System.out.println(prop.getProperty("itheima0011"));

//        System.out.println(prop);

        //Set<String> stringPropertyNames(): Returns an unmodifiable set of keys from this property list, where the keys and their corresponding values ​​are strings
        Set<String> names = prop.stringPropertyNames();
        for (String key : names) {
//            System.out.println(key);
            String value = prop.getProperty(key);
            System.out.println(key + "," + value);
        }
    }
}

public class PropertiesDemo03 {
    public static void main(String[] args) throws IOException {
        //Save the data in the collection to a file
//        myStore();

        //Load the data from the file into the collection
        myLoad();

    }

    private static void myLoad() throws IOException {
        Properties prop = new Properties();

        //void load(Reader reader): 
        FileReader fr = new FileReader("myOtherStream\\fw.txt");
        prop.load(fr);
        fr.close();

        System.out.println(prop);
    }

    private static void myStore() throws IOException {
        Properties prop = new Properties();

        prop.setProperty("itheima001","Tong Liya");
        prop.setProperty("itheima002","Zhao Liying");
        prop.setProperty("itheima003","Liu Shishi");

        //void store(Writer writer, String comments): 
        FileWriter fw = new FileWriter("myOtherStream\\fw.txt");
        prop.store(fw,null);
        fw.close();
    }
}

public class Student implements Serializable {
    private static final long serialVersionUID = 1L;

    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

public class Test {

    public static void main(String[] args) throws IOException {
      	//1. Create a Properties collection and load the data in the local file into the collection
        Properties prop = new Properties();
        FileReader fr = new FileReader("prop.properties");
        prop.load(fr);
        fr.close();
		//2. Get the key-value pair data in the collection and encapsulate it into the student object
        String name = prop.getProperty("name");
        int age = Integer.parseInt(prop.getProperty("age"));
        Student s = new Student(name,age);
		//3. Create a serialized stream object and serialize the student object into a local file
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("a.txt"));
        oos.writeObject(s);
        oos.close();
    }
}