Mock Test 3   1.class C{ static int f1(int i) { System.out.print(i + ","); return 0; } public static void main (String[] args) { int i = 0; i = i++ + f1(i); System.out.print(i); }} What is the result of attempting to compile and run the program? 1.Prints: 0,0 2.Prints: 1,0 3.Prints: 0,1 4.Compile-time error 5.None of the above Answer: 2 2) class C{ static String m(int i) {return "int";} static String m(float i) {return "float";} public static void main (String[] args) { long a1 = 1; double b1 = 2; System.out.print(m(a1)+","+ m(b1)); }} What is the result of attempting to compile and run the program?   1.Prints: float,double 2.Prints: float,float 3.Prints: double,float 4.Compile-time error 5.None of the above Answer: 4 3) class C { public static void main(String a[]) { C c1=new C(); C c2=m1(c1); C c3=new C(); c2=c3; //6 anothermethod(); } static C m1(C ob1){ ob1 =new C(); return ob1; } } After line 6, how many objects are eligible for garbage collection? 1.     1 2.     2 3.     3 4.     4 5.      None of the above Answer: 2 4) 1. StringBuffer s1 = new StringBuffer("abc"); 2. StringBuffer s2 = s1; 3. StringBuffer s3 = new StringBuffer("abc"); How many objects are created ? 1.  0 2.  1 3.   2 4.  3 Answer : 4 5) class c2 { { System.out.println("initializer"); } public static void main(String a[]) { System.out.println("main"); c2 ob1=new c2(); } } What is the result of attempting to compile and run the program? 1.prints main and initializer 2.prints initializer and main 3.compile time error 4.None of the above Answer: 1 6) class c1 { public static void main(String a[]) { c1 ob1=new c1(); Object ob2=ob1; System.out.println(ob2 instanceof Object); System.out.println(ob2 instanceof c1); } } What is the result of attempting to compile and run the program? 1.Prints true,false 2.Print false,true 3.Prints true,true 4.compile time error 5.None of the above Answer: 3 7) class A extends Thread { private int i; public void run() {i = 1;} public static void main(String[] args) { A a = new A(); a.run(); System.out.print(a.i); }} What is the result of attempting to compile and run the program?   1.Prints nothing 2.Prints: 1 3.Prints: 01 4.compile-time error 5.None of the above Answer: 2 Explanation: a.run() method was called instead of a.start(); so the full program runs as a single thread so a.run() is guaranteed to complete 8) class bike { } class arr extends bike{ public static void main(String[] args) { arr[] a1=new arr[2]; bike[] a2; a2=a1; //3 arr[] a3; a3=a1; //5 }} What is the result of attempting to compile and run the program? 1.compile time error at line 3 2.compile time error at line 5 3.Runtime exception 4.The code runs fine 5.None of the above Answer: 4 Explanation: bike is the superclass of arr.so they are compatible(superobject=subobject) but subobject=superobject not allowed 9) class C{ public static void main (String[] args) { String s1="hjhh"; // 1 String s2="u0002"; //2 String s3="''"; //3 }} What is the result of attempting to compile and run the program? 1.compile time error at line 1 2.compile time error at line 2 3.compile time error at line 3 4.Runtime exception 5.the code runs without any error Answer: 5 Explanation: A String literal is a sequence of characters enclosed in double quotes 10) Which data type is wider for the purpose of casting: float or long? 1.float 2.long Answer: 1 Explanation: float is wider than long, because the entire range of long fits within the range of float.