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单选题
在Java中,下列代码将输出()。  1.    public class integerequals  2.    {  3.       public static void main (String args[])  4. {  5.  Integer a= new Integer(3);  6.  Integer b= new Integer(3);  7.   System.out.println(a==b);  8. }  9.    }
A

编译器将显示第7行有错误

B

程序编译并打印true

C

程序编译并打印false

D

程序编译但在第7行引起了一个运行期意外


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参考解析
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