package two.string.mushroom;
public class TestTwoString 
{
 public static void main(String[] args)
  {
  String str1 = "AA";
  String str2 = "AA";
  String str3 = new String("AA");
  System.out.println("str1 == str2: " + (str1 == str2));
  //它们都指向字符串常量池中的 "AA"，true
  System.out.println("str1 == str3: " + (str1 == str3));
  //它们本身指向不同，false
  //String类重写了equals方法，实际上比较的是字符串的内容是否相等，true
  System.out.println("str1.equals(str3): " + (str1.equals(str3)) );
  Animal p1 = new Animal("AA",10);
  Animal p2 = new Animal("AA",12);
  //因为构造器中的方式是直接指向字符串常量池的，所以也是true
  System.out.println("p1.name == p2.name: " + (p1.name == p2.name));
 }
}
class Animal
{
 String name;
 int age;
 Animal(String name,int age)
  {
  this.name = name;
  //构造器中的方式是直接指向字符串常量池的
  this.age = age;
 }
}

str1 == str2: true 
str1 == str3: false 
str1.equals(str3): true 
p1.name == p2.name: true