设有如下代码段1Strings=null;2if(s!=null&s.length()>0)3System.out.println("s!=null&s.length()>0"); A: 6,8 B: 2,4,6,8 C: 2,6,8 D: 2,4

设有如下代码段 1 String s = null; 2 if ( s != null & s.length() > 0) 3 System.out.println("s != null & s.length() > 0"); 4 if ( s != null && s.length() > 0) 5 System.out.println("s != null & s.length() > 0"); 6 if ( s != null || s.length() > 0) 7 System.out.println("s != null & s.length() > 0"); 8 if ( s != null | s.length() > 0) 9 System.out.println("s != null | s.length() > 0"); 哪些行将抛出空指针异常?

设有如下代码段 1 String s = null; 2 if ( s != null & s.length() > 0) 3 System.out.println("s != null & s.length() > 0"); 4 if ( s != null && s.length() > 0) 5 System.out.println("s != null & s.length() > 0"); 6 if ( s != null || s.length() > 0) 7 System.out.

设有如下代码段 1 String s = null 2 if ( s != null

设有一个串s,和一个int型变量i,以下那条语句可能产生异常？ A: if ((s !=null) && ( i ==s.length())) B: if ((s ==null) && ( i ==s.length())) C: if ((s !=null) || ( i ==s.length())) D: if ((s ==null) || ( i ==s.length()))

设有如下代码段 1Strings=null; 2if(s!=null

若用如下的SQL语句创建一个表S： CREATE TABLE S(Sno CHAR(6) NOT NULL, Sname CHAR(8) NOT NULL,s ex CHAR(2),age INT) 可向表S中插入的是（） A: (‘991001’,’李明芳’,女,’23’) B: (‘990746’,’张明’, NULL , NULL) C: ( NULL,‘陈道明’,’男’, 35 ) D: (’992345’, NULL,’女’, 25 )

– What’s the model plane look like?- Well, the wings of the plane are of its body. A: more than the length twice B: twice more than the length C: more than twice the length D: more twice than the length

要获得字符串s长度,可采用__________ A: s.len() B: s.length C: len(s) D: length(s)

In a copy, don’t say it’s “27 meters long”, say it’s “27 meters in length”. （ ）