对String对象的操作和理解

1.字符串比较结果

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String a = "abc";String b = "abc";String c = new String("abc");String d = new String("abc");System.out.println(a == b);//trueSystem.out.println(a == c);//falseSystem.out.println(c == d);//falseSystem.out.println(a.equals(b));//trueSystem.out.println(a.equals(c));//trueSystem.out.println(c.equals(d));//trueSystem.out.println(a == c.intern());//trueSystem.out.println(c.intern() == d.intern());//trueSystem.out.println(d == d.concat(""));//true

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2.String重写了equals方法

相同的字符串使用equals比较始终相等

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