String Compare in Java

String Compare in Java

There are three way to compare string object in java:

• By equals() method
• By == operator
• By compreTo() method

equals() Method in Java

equals() method always used to comparing contents of both source and destination String. It return true if both string are same in meaning and case otherwise it returns false. It is case sensitive method.

class StringHandling
{
public static void main(String arg[])
{
String s1="Hitesh";
String s2="Raddy"; 
String s3="Hitesh";
System.out.println("Compare String: "+s1.equals(s2));
System.out.println("Compare String: "+s1.equals(s3));
}
}

Compare String: false
Compare String: true

== or Double Equals to Operator in Java

== Operator is always used for comparing references of both source and destination objects but not their contents.

class StringHandling
{
public static void main(String arg[])
{
String s1=new String("java");
String s2=new String("java");
if(s1==s2)
{
System.out.println("Strings are same");
}
else
{
System.out.println("Strings are not same");
}
}
}

Strings are not same

compareTo() Method in Java

comapreTo() method can be used to compare two string by taking Unicode values. It returns 0 if the string are same otherwise returns either +ve or -ve integer.

class StringHandling
{
public static void main(String arg[])
{
String s1="Hitesh";
String s2="Raddy";
int i;
i=s1.compareTo(s2);
if(i==0)
{
System.out.println("Strings are same");
}
else
{
System.out.println("Strings are not same");
}
}
}

Strings are not same

Difference between equals() method and == operator

equals() method always used to comparing contents of both source and destination String.

== Operator is always used for comparing references of both source and destination objects but not their contents.