Boolean

Boolean Wrapper Class in Java

Overview

The Boolean wrapper class in Java provides a way to use a boolean value as an object. It belongs to the java.lang package and is useful when working with collections like ArrayList that require objects rather than primitives.

---

Characteristics of Boolean Wrapper Class

Feature	Details
Package	java.lang
Default Value	false
Immutable	Boolean objects are immutable.
Constants	Boolean.TRUE and Boolean.FALSE Boolean value = Boolean.FALSE; System.out.println(value); // false

---

Static Methods

Method	Description	Return Type	Example
valueOf(boolean)	Returns a Boolean instance representing the specified boolean value.	Boolean	Boolean.valueOf(true);
valueOf(String)	Returns a Boolean instance representing the value of the specified String.	Boolean	Boolean.valueOf("true");
parseBoolean(String)	Parses the String argument as a boolean.	Boolean	Boolean.parseBoolean("true");
compare(boolean, boolean)	Compares two boolean values.	int	Boolean.compare(true, false);
logicalAnd(boolean boolean)	Performs a logical AND on two values.	boolean	rBoolean.logicalAnd(true, false);
logicalOr(boolean, boolean)	Performs a logical OR on two values.	boolean	Boolean.logicalOr(true, false);
logicalXor(boolean, boolean)	Performs a logical XOR on two values.	boolean	Boolean.logicalXor(true, false);
getBoolean(String)	Returns the value of the system property as a Boolean.	Boolean	Boolean.getBoolean("propName");

---

Instance Methods

Boolean value = Boolean.TRUE // Using Boolean.TRUE instead of primitive boolean

Method	Description	Return Type	Example
booleanValue()	Returns the primitive boolean value of this Boolean object.	boolean	value.booleanValue();
toString()	Returns a String representation of this Boolean.	String	value.toString();
equals(Object)	Compares this Boolean to another object.	Boolean	value.equals(true);
compareTo(Boolean)	Compares this Boolean object to another Boolean.	int	value.compareTo(false);
hashCode()	Returns the hash code for this Boolean object.	int	value.hashCode();

---

Boolean Operations

Logical Operators

Operation	Symbol	Description	Example
AND	&&	Returns true if both operands are true.	booleanValue1 && booleanValue2
OR	||	Returns true if at least one operand is true.	booleanValue1 || booleanValue2
NOT	!	Reverses the value of the operand.	!booleanValue1

Relational Operators

Operation	Symbol	Description	Example
Equal to	==	Returns true if both values are equal.	booleanValue1 == booleanValue2
Not equal to	!=	Returns true if values are not equal.	booleanValue1 != booleanValue2

---

Boolean Operators and Their Equivalent Methods

Boolean value1 = Boolean.TRUE // Using Boolean.TRUE instead of primitive boolean
Boolean value2 = Boolean.TRUE // Using Boolean.TRUE instead of primitive boolean

Operator	operator usage	Equivalent Method	usage
==	value1 == value2; // true	equals(Object)	value1.equals(value2); // true
!=	value1 != value2; // false	!equals(Object)	!value1.equals(value2); // false
`		`	value1 || value2; // true
&&	value1 && value2; // false	logicalAnd(boolean, boolean)	logicalAnd(value1, value2) // false
XOR	(!value1 && value2) || (value1 && !value2); // false	logicalXor(boolean, boolean)	logicalXor(value1, value2) // false

---

Key Features of the Boolean Class

• Immutability: Boolean objects are immutable, meaning their value cannot be changed once created.

---

Example Code

public class BooleanWrapperExample {
    public static void main(String[] args) {
        // Static Methods
        
        // Returns a Boolean object, true
        Boolean b1 = Boolean.valueOf(true); 
        // Converts the string "true" to the primitive boolean type, which is true
        boolean b2 = Boolean.parseBoolean("true"); 
        // Compares two boolean values; returns 1 (since true is greater than false)
        int compareResult = Boolean.compare(true, false); 
        // Returns the result of logical AND operation; false (since one operand is false)
        boolean andResult = Boolean.logicalAnd(true, false); 
        // Returns the result of logical OR operation; true (since one operand is true)
        boolean orResult = Boolean.logicalOr(true, false); 
        // Returns the result of logical XOR operation; true (since operands are different)
        boolean xorResult = Boolean.logicalXor(true, false); 
        
        // Instance Methods
        
        // Converts the Boolean object to a primitive boolean; true
        boolean primitiveValue = b1.booleanValue(); 
        // Converts the Boolean object to a String; "true"
        String stringValue = b1.toString(); 
        // Compares the Boolean object with Boolean.FALSE; false (b1 is true, not false)
        boolean isEqual = b1.equals(Boolean.FALSE); 
        // Compares the Boolean objects; returns 1 (since true > false)
        int compareToResult = b1.compareTo(Boolean.FALSE); 
        // Returns the hash code for the Boolean object; 1231 for true
        int hashCode = b1.hashCode(); 
    }
}

For more: BooleanWrapperClass.java