Java-Day2

Given the following declaration, which expression returns the size of the array,

assuming the array has been initialized?

int[] array;

Select the one correct answer

• array[].length()

• array.length()

• array[].length

• array.length

• array[].size()

Is it possible to create arrays of length zero?

Select the one correct answer.

• Yes, you can create arrays of any type with length zero.

• Yes, but only for primitive data types.

• Yes, but only for arrays of reference types.

• No, you cannot create zero-length arrays, but the main() method may be passed

  a zero-length array of Strings when no program arguments are specified.

• No, it is not possible to create arrays of length zero in Java

Which one of the following array declaration statements is not legal?

Select the one correct answer

• int []a[] = new int [4][4];

• int a[][] = new int [4][4];

• int a[][] = new int [][4];

• int []a[] = new int [4][];

• int [][]a = new int [4][4];

Which of these array declaration statements are not legal?

Select the two correct answers.

• int[] i[] = { { 1, 2 }, { 1 }, {}, { 1, 2, 3 } };

• int i[] = new int[2] {1, 2};

• int i[][] = new int[][] { {1, 2, 3}, {4, 5, 6} };

• int i[][] = { { 1, 2 }, new int[ 2 ] };

• int i[4] = { 1, 2, 3, 4 };

What would be the result of compiling and running the following program?

• The code will not compile, because the array type int[] is incorrect.

• The program will compile, but will throw an ArrayIndexOutOfBoundsException

  when run.

• The program will compile and run without error, but will produce no output.

• The program will compile and run without error, and will print the numbers

  0 through 19.

• The program will compile and run without error, and will print 0 twenty

  times

What would be the result of compiling and running the following program?

• The program will fail to compile because of uninitialized variables.

• The program will throw a java.lang.NullPointerException when run.

• The program will print: 0 false NaN null.

• The program will print: 0 false 0 null.

• The program will print: null 0 0 null.

What will be printed when the following program is run?

• 0

• 1

• 2

• 3

What will be the result of compiling and running the following program?

• The code will fail to compile, since x[0]++; is not a legal statement.

• The code will compile and will print "a=1 b=1 bArr[0]=1", when run.

• The code will compile and will print "a=0 b=1 bArr[0]=1", when run.

• The code will compile and will print "a=0 b=0 bArr[0]=1", when run.

• The code will compile and will print "a=0 b=0 bArr[0]=0", when run.

Which statements, when inserted at (1), will cause a compilation error?

Select the two correct answers.

• a++;

• b++;

• b = a;

• c[0]++;

• c = d;

Which method declarations are valid declarations?

Select the three correct answers.

• void compute(int... is) { }

• void compute(int is...) { }

• void compute(int... is, int i, String... ss) { }

• void compute(String... ds) { }

• void compute(char[] ca, int... is) { }