81.Byte index=1;
While (index++>0) ;
System.out.println(“a”);
While(--index<0) ;
System.out.println(“b”); a和b都可以打印出来,因为byte 是有最大值的。然后就变成最小的值了。(-128-127)
82.The use of thrad priority depends on the thread scheduling algorithm used to implement the JVM and can vary by platform
83. static and non-static method can’t be overridden by each other
84.final int one=1;
Switch(x)
{
Case one: ******
} // 这是正确的,如果没有final ,则编译错误
85.Byte g=2;
Switch(g)
{
Case 2: ***
Case 128:****
}//编译错误,因为128超过了byte的最大值
86.Try() catch(){} finally{} 每一部门之间不可以有任何的语句
87.It is legal for a program to have more than more static initializer.
88. how many objects will be garbage collected<> how many objects are eligible for gc.
89. 只有long和int 有toHexString(long l or int i) 的方法,连short都没有
90.StringBuffer constructor with no arguments has an initial capacity of 16 chars.
91. LastIndexOf 中arguments中fromindex为最末尾的限制,例如:
StringBuffer sb=new StringBuffer(“abcddabcddabc”);
LastIndexOf(“abc”,9)=5
不过要注意以下也是对的
LastIndexOf(“abc”,0)=0
LastIndexOf(“abc”,1)=0
LastIndexOf(“abc”,2)=0 这些可能比较相对位置的
92.System.in System.out System.err
93. thread------destroy() destroy this thread without any cleanup
94. a extends Thread
a aa=new a();
aa.setPriority(s); s的范围是[1-10] 否则会编译错误[illegalAugumentException]
95. assert expression1
assert expression1:expression2
其中:expression1 must be a Boolean expression2 must be a expression
96.初始化时先初始静态变量,再初始static block
97.Throwable à Error à AssertionError
98. null instanceof String = false null instanceof null 会编译错误
99.动态绑定只对子类可以访问父类的方法时有效,若父类private,子类public ,则不用动态绑定
100.a.equals(b) a和b不是一个类型也不编译错误 a==b 不是同一类型,会编译错误
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