韩顺平Java38——IO流homework

1.

package homework;

import java.io.*;

/**
 * @author 紫英
 * @version 1.0
 * @discription
 */
@SuppressWarnings("all")
public class Homework01 {
    public static void main(String[] args) throws IOException {
        String dirPath = "E:\\mytemp";
        File file = new File(dirPath);
        if (file.exists()) {
            System.out.println("目录已存在");
        } else {
            if (file.mkdir()) {
                System.out.println("目录创建成功！");
            } else {
                System.out.println("目录创建失败！");

            }
            System.out.println("目录不存在可以创建");
        }
        File file2 = new File(dirPath, "hello.txt");
        if (!file2.exists()) {
            file2.createNewFile();
            System.out.println("hello.txt创建成功");

        } else {
            System.out.println("文件已存在");
        }
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(file2));
        bufferedWriter.write("hello,world!");
        bufferedWriter.close();//一定记得关！！！！！
        System.out.println("写入成功");

    }
}

 

2.

 

package homework;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

/**
 * @author 紫英
 * @version 1.0
 * @discription
 */
public class Homework02 {
    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new FileReader("e:\\a.txt"));
       String s = null;
       int i =0;
       while ((s=bufferedReader.readLine())!=null){
           System.out.println(++i +" "+ s);
       }
       bufferedReader.close();


    }
}

 

 

修改一下:

     BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream("e:\\a.txt"),"gbk"));

又正常了！

3.

 

 

package homework;

import java.io.*;
import java.util.Properties;

/**
 * @author 紫英
 * @version 1.0
 * @discription
 */
public class Homework03 {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        Properties properties = new Properties();
        properties.load(new FileReader("src\\dog.properties"));
        properties.list(System.out);
        Dog dog = new Dog(properties.getProperty("name"), Integer.parseInt(properties.getProperty("age")), properties.getProperty("color"));
        System.out.println("dog对象信息" + dog);

        String filePath = "e:\\dog.dat";
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(new FileOutputStream(filePath));
        objectOutputStream.writeObject(dog);
        objectOutputStream.close();
        System.out.println("序列化输出完毕");
        ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream(filePath));
        System.out.println("反序列化读取结果：" + objectInputStream.readObject());
        objectInputStream.close();



    }
}

class Dog implements Serializable {
    String name;
    int age;
    String color;

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

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


}