Compare char with char in java

How to compare chars in Java?

If you are wondering how to compare chars in java, then this article is for you. There are various ways to compare characters in Java language. We can either define the characters using char datatype or we can use Character class. Both are equally good and acceptable.

Compare chars, if defined using char datatype

Defined like this – char firstChar = ‘A’;

a. Using ==

b. Using Character.compare(char1, char2)

There are 3 possible outputs (if provided parameters are characters) –

• 0 – If both characters are equal.
• Negative number – If char1 is smaller than char2. For ex – char1 = A and char2 = B.
• Positive number – If char1 is larger than char2.

c. Using Character.hashCode(char)

You can calculate hasCode for your characters and then compare using if/else conditions.

public class Main < public static void main(String[] args) < char firstChar = 'H'; char secondChar = 'E'; char thirdChar = 'H'; int firstCharHashCode = Character.hashCode(firstChar); int secondCharHashCode = Character.hashCode(secondChar); int thirdCharHashCode = Character.hashCode(thirdChar); System.out.println(firstCharHashCode - secondCharHashCode); // Output: 3 (positive - first char >second char) System.out.println(firstCharHashCode - thirdCharHashCode); // Output: 0 (first char is same as third char) > >

If defined using Character class

Defined like this – Character firstCharObj = new Character(‘A’);

a. Using compareTo()

Its syntax is firstCharObj.compareTo(secondCharObj)

b. Using equals()

This will check if two characters are equal or not.

c. Using getNumericValue()

System.out.println(firstCharNumericVal > secondCharNumericVal); // True | False

d. Using Character.hashCode(charObj)

hashCode() method works with both characters and characters objects.

e. Using charObj.hashCode()

Apart from static method, there is also a public method to call on object directly.

f. Using charObj.charValue()

charValue() returns the character from object. So if your object is –

Character charObj = new Character(‘c’);

then, charObj.charValue() will return c.

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Compare Characters in Java

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1. Overview

In this short tutorial, we’ll explore different ways to compare characters in Java.

We’ll start by discussing how to compare primitive characters. Then, we’ll look at different methods of comparing Character objects.

2. Comparing Primitive Characters

Firstly, let’s begin by highlighting how to compare primitive characters.

2.1. Using Relational Operators

Typically, the simplest way to compare characters is using the relational operators.

In short, characters are compared in Java depending on the order of their ASCII code:

assertFalse('a' == 'A'); assertTrue('a' < 'v'); assertTrue('F' >'D'); 

2.2. Using Character.compare() Method

Similarly, another solution would be using the compare() method of the Character class.

Simply put, the Character class wraps a value of the primitive type char in an object. The compare() method accepts two char parameters and compares them numerically:

assertTrue(Character.compare('C', 'C') == 0); assertTrue(Character.compare('f', 'A') > 0); assertTrue(Character.compare('Y', 'z') < 0); 

As shown above, the compare(char a, char b) method returns an int value. It denotes the difference between the ASCII code of a and b.

The returned value is equal to zero if the two char values are identical, less than zero if a < b, and greater than zero otherwise.

3. Comparing Character Objects

Now that we know how to compare primitive characters, let's see how to compare Character objects.

3.1. Using Character.compareTo() Method

The Character class provides the compareTo() method to compare two character objects numerically:

Character chK = Character.valueOf('K'); assertTrue(chK.compareTo(chK) == 0); Character chG = Character.valueOf('G'); assertTrue(chK.compareTo(chG) > 0); Character chH = Character.valueOf('H'); assertTrue(chG.compareTo(chH) < 0); 

Here, we used the valueOf() method to create Character objects since the constructor is deprecated since Java 9.

3.2. Using Object.equals() Method

Moreover, one of the common solutions to compare objects is using the equals() method. It returns true if the two objects are equal, false otherwise.

So, let's see how we can use it to compare characters:

Character chL = 'L'; assertTrue(chL.equals(chL)); Character chV = 'V'; assertFalse(chL.equals(chV)); 

3.3. Using Objects.equals() Method

The Objects class consists of utility methods for operating on objects. It offers another way to compare character objects through the equals() method:

Character chA = 'A'; Character chB = 'B'; assertTrue(Objects.equals(chA, chA)); assertFalse(Objects.equals(chA, chB)); 

The equals() method returns true if the character objects are equal to each other and false otherwise.

4. Conclusion

In this article, we learned a variety of ways to compare primitive and object characters in Java.

As always, the code used in this article can be found over on GitHub.

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How to Compare Characters in Java

In this tutorial, I will be sharing how to compare characters in java. Characters can be a char primitive data type or Character wrapper class. Let's dive deep into the topic:

1. Comparing char primitives

1. Using , == operators

Based on the Unicode table, the char primitive data type also has the associated integer value. Using ==, <, >operators you should be able to compare two characters just like you compare two integers.

public class JavaHungry  public static void main(String args[])  char ch1 = 'A'; char ch2 = 'B'; char ch3 = 'A'; System.out.println(ch1==ch2); System.out.println(ch1ch2); System.out.println(ch3==ch1); > > 

Output:
false
true
true

2. Using Character.compare(char x, char y)

We can compare the char values numerically by using compare(char x, char y) method of Character class.

Note: Comparing char primitive values using Character.compare(char x, char y) method returns an integer value.

According to Java docs,
The compare(char a, char b) method of Character class returns the following values:
0, if (a == b)
value less than 0, if a < b
value greater than 0, if a > b

public class JavaHungry  public static void main(String args[])  char ch1 = 'X'; char ch2 = 'Y'; char ch3 = 'X'; System.out.println(Character.compare(ch1,ch2)); System.out.println(Character.compare(ch2,ch3)); System.out.println(Character.compare(ch1,ch3)); > > 

2. Comparing Character objects

You can compare Character class objects:

1. Using Character.compare(char x, char y)

Using Character class constructor, we can convert the char primitive value to the Character object.

public class JavaHungry  public static void main(String args[])  Character ch1 = new Character('X'); Character ch2 = new Character('Y'); Character ch3 = new Character('X'); System.out.println(Character.compare(ch2,ch3)); System.out.println(Character.compare(ch1,ch3)); 

System.out.println(Character.compare(ch1,ch2)); 

Output:
1
0
-1

2. Using equals() method

Using equals() method also we can compare the Character class objects.

public class JavaHungry  public static void main(String args[])  Character ch1 = new Character('X'); Character ch2 = new Character('Y'); Character ch3 = new Character('X'); System.out.println(ch1.equals(ch2)); System.out.println(ch2.equals(ch3)); System.out.println(ch1.equals(ch3)); > > 

Output:
false
false
true

That's all for today, please mention in comments in case you have any questions related to how to compare characters in java.

About The Author

Subham Mittal has worked in Oracle for 3 years.
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