一文让你彻底明白Java中的值传递和引用传递

public class Demo {
    public static void main(String[] args) {
        int num1 = 10;
        int num2 = 20;
        work(num1, num2);
        System.out.println("num1 = " + num1);
        System.out.println("num2 = " + num2);
    }
    public static void work(int a, int b) {
        int temp = a;
        a = b;
        b = temp;
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        System.out.println("a = " + a);
        System.out.println("b = " + b);
    }
}

public class ArrayListDemo {
    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 4, 5};
        change(arr);
        System.out.println(arr[0]);
    }
    public static void change(int[] array) {
        System.out.println(array[0]);
        array[0] = 0;
    }
}

public class Demo {
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    public static void main(String[] args) {
        StringBuffer stringBuffer = new StringBuffer("北京异乡人");
        System.out.println(stringBuffer);
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        changeStringBuffer(stringBuffer);
        System.out.println(stringBuffer);
    }
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    public static void changeStringBuffer(StringBuffer stringBuffer) {
        stringBuffer = new StringBuffer("河北异乡人");
        stringBuffer.append(",哈哈哈");
    }
}

public static void changeStringBuffer(StringBuffer stringBuffer) {
    stringBuffer.append(",欢迎大家关注");
}

public class Demo {
    public static void main(String[] args) {
        String str = new String("北京异乡人");
        System.out.println(str);
        changeString(str);
        System.out.println(str);
    }
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    public static void changeString(String string) {
        string = new String("河北异乡人");
    }
}

public class Person {
    private String name;
    public String getName() {
        return name;
    }
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    public void setName(String name) {
        this.name = name;
    }
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    public Person(String name) {
        this.name = name;
    }
}
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public class ArrayListDemo {
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    public static void main(String[] args) {
        Person person = new Person("李四");
        System.out.println(person.getName());
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        changePerson(person);
        System.out.println(person.getName());
    }
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    public static void changePerson(Person p) {
        Person person = new Person("张三");
        p = person;
    }
}

public static void changePerson(Person p) {
    p.setName("张三");
}