Lesson 9	Using Java's Boolean, String, and assignment operators
Objective	Examine Boolean, string, and assignment operators in Java.

Java Boolean, String, Assignment Operators

Java also supports a number of Boolean, string, and assignment operators.
Boolean operators are used to perform logical comparisons, and always result in one of two values: true or false. Following are the most commonly used Boolean operators:

AND, OR, Negation, Equal-to, Not Equal-to

1) AND: Compares two values and returns true if they are both true

2) OR: Compares two values and returns true if either of the values are true

4) Equal-to: Compares two values for equality

5)Not-equal-to (!=): Compares two values for inequality — 5) Not-equal-to (!=): Compares two values for inequality

Given the following Class:

class BooleanTest1 {
 public static void main(String[] args) {
  boolean b1 = false;
  int i1 = 2;
  int i2 = 3;
  if (b1 = i1 == i2) {
   System.out.println("true");
  }
  else {
   System.out.println("false");
  }
 } 
}

Select 1 option

Compile time error.
It will print true
It will print false
Runtime error.
It will print nothing.

Answer: c
Explanation:

All an if statement needs is a boolean. Now i1 == i2 returns false which is a boolean and since b1 = false is an expression and every expression has a return value (which is actually the Left Hand Side of the expression), it returns false which is again a boolean. Therefore, in this case, the else condition will be executed.

AND: Compares two values and returns true if they are both true
OR: Compares two values and returns true if either of the values are true
Negation: Flips the state of a value
Equal-to: Compares two values for equality
Not-equal-to: Compares two values for inequality

Java String Operators

There is only one string operator, the concatenation operator (+), which appends a string onto another string. Following is an example of using the concatenation operator:

String nickname = "tough guy";
String message = "Hey there, " + nickname + "!";

The nickname string is effectively placed in the middle of a sentence. This code acts somewhat like a form letter in that you provide a sentence and then plug a name into it.

Assignment operators

Assignment operators all perform some type of operation that results in a value being stored in a variable. The following link contains the most commonly used assignment operators:

prime Application - Exercise

In this exercise, You will create a command-line application to determine whether a number is prime.
prime Application - Exercise