字符串比较之 “==”和 “equals”

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?? ??? Stringa = "String A";

??????? String b = new String("StringB");

??????? String c = a;

????? System.out.println(a.hashCode());

??????? System.out.println(b.hashCode());

??????? System.out.println(c.hashCode());

??????? System.out.println(d.hashCode());

??????? System.out.println(a==c);

System.out.println(b==d);

??????? System.out.println(a.equals(c));

??????? System.out.println(b.equals(d));

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true //a==c

false//b!=d

true//a.equals(c)

true//b.equals(d)

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