61．Numeric expressions always result in at least int-sized result –never smaller.
62. Float-point numbers are implicitly doubles (64-bits)
63. Compound assignments (+=) perform an automatic cast.
64.shift operators can only be used on integers (octal,decimal,or Hexdecimal)
65.Threading and garbage collection are two of the few areas that are platform dependent.This
Is one of the reasons why Java is not suitable or realtime programming.
66.考试中也许会出现没有正确答案的情况
67．You may access methods of a direct parent class through the use of super but classes further up the hierarchy are not visible.
68.float f=1/3; (right)
69.All the integer primitives in java are signed number (wrong because of char)
70.There are no restrictions on the level of nesting for inner/nested classes ( 内部类没有层数的限制)
71．Yield() is a static method and cause whatever thread is currently executing to yield its cycles.
72 switch(k) k may be char short int byte
73 Math.round(float) = int Math.round(double) = long
74.Math.round(4.5)=5 Math.round(－4.5)=－4
75．Float f=-21364750f Math.round(f)=－21364748
76.flat f=42.0f int i=42 i==f true
77.instanceof 比较的必须是同一hierarchy 的引用和类，否则编译不过
78．Boolean b=new Boolean(true); b=true
Boolean b=new Boolean(“true”); b=true
Boolean b=new Boolean(false); b=false
Boolean b=new Boolean(“false”); b=false
Boolean b=new Boolean(“asdf”); b=false
Boolean b=new Boolean(asdf); compiler error
Boolean b=new Boolean(TrUe); compiler error
79. long x=32;
x=x>>37; x=0
x=x>>69 x=1 只有位数大于64的时候才取module
80．Float a=Integer.MIN_VALUE
Float b=Integer.MAX_VALUE
Math.round(a)=-21364748
Math.ceil(a)=－2.1364748E9
Math.floor(a)=－2.1364748E9
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