Java forEach对原数组的操作过程

@Test
    public void testInt(){
        int[] arr = new int[]{1,2,3,4,5};
        //使用foreach遍历arr数组
        for(int i : arr){
            //如果i=2，那么就将i值变为0
            if(i == 2){
                i = 0;
            }
        }
        //遍历数组
        for(int i : arr){
            System.out.print(i + " ");
        }

 	@Test
    public void testString(){
        String[] strAll = new String[]{"aa","bb","cc"};
        for(String str : strAll){
            if("bb".equals(str)){
                str = "xx";
            }
        }
        for(String str : strAll){
            System.out.print(str + " ");
        }
    }

@Test
    public void testStringBuilder(){
        StringBuilder[] strBul = new StringBuilder[]{new StringBuilder("111"), new StringBuilder("222"), new StringBuilder("333")};
        for(StringBuilder s : strBul){
            //StringBuilder并没有重写equals,所以如果直接调用的话，它是比较的地址值。
            if("222".equals(s.toString())){
                s.append("aaa");
            }
        }
        for(StringBuilder s : strBul){
            System.out.println(s);
        }

public class TestForeach {
    Person[] pArr = new Person[]{new Person("张三",18),new Person("李四",20),new Person("王六",10)};
    public void foreachTestPerson(){
        for(Person p : pArr){
            if("王六".equals(p.name)){
                p.age = 100;
            }
        }
        for(Person p : pArr){
            System.out.println(p);
        }
    }
    public static void main(String[] args) {
        new TestForeach().foreachTestPerson();
    }
}
class Person{
    public String name;
    public int age;
    public Person(String name, int age) {
        this.name = name;
        this.age = age;
    }
    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", id=" + age +
                '}';
    }
}