格林模拟试题二(上)(6)

  question 17)

which statements are correct about the anchor field?

1) it is a field of the gridbaglayout manager for controlling component placement
3) a valid setting for the anchor field is gridbagconstraints.north

question 18)

what will happen when you attempt to compile and run the following code?

public class bground extends thread{
bground b = new bground();
}
for (int i = 0; i < 10; i++){
}
}
1) a compile time error indicating that no run method is defined for the thread class
3) clean compile and at run time the values 0 to 9 are printed out

question 19)

is the following statement true or false?

1) true

||| question 20)

which most closely matches a description of a java map?

1) a vector of arrays for a 2d geographic representation
3) a class for containing unique vector elements

question 21)

how does the set collection deal with duplicate elements?

1) an exception is thrown if you attempt to add an element with a duplicate value
3) a set may contain elements that return duplicate values from a call to the equals method