Java中String原理

电玩女神 2021-09-30 04:56 286阅读 0赞

package t2;
    
    public class T1 {
        public static void main(String[] args) {
            String str1= "abc";
            String str2= new String("abc");
            String str3= str2.intern();
            assertSame(str1==str2);
            assertSame(str2==str3);
            assertSame(str1==str3);
            System.out.println("-----");
            assertSame(str1.equals(str2));
            assertSame(str2.equals(str3));
            assertSame(str1.equals(str3));
        }
    
        private static void assertSame(boolean b) {
            System.out.println(b);
        }
    }

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### jvm会对string进行优化 ###

### string的intern()方法会优化string，首先去常量池里面看有没有。 ###

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