5/19/2021 Java String - javatpoint
Java String
In Java, string is basically an object that represents sequence of char values. An array
of characters works same as Java string. For example:
char[] ch={'j','a','v','a','t','p','o','i','n','t'};
String s=new String(ch);
is same as:
String s="javatpoint";
Java String class provides a lot of methods to perform operations on strings such as
compare(), concat(), equals(), split(), length(), replace(), compareTo(), intern(),
substring() etc.
The java.lang.String class implements Serializable, Comparable and CharSequence
interfaces.
CharSequence Interface
⇧
https://www.javatpoint.com/java-string 1/8
, 5/19/2021 Java String - javatpoint
The CharSequence interface is used to represent the sequence of characters. String,
StringBuffer and StringBuilder classes implement it. It means, we can create strings in
java by using these three classes.
The Java String is immutable which means it cannot be changed. Whenever we change
any string, a new instance is created. For mutable strings, you can use StringBuffer and
StringBuilder classes.
We will discuss immutable string later. Let's first understand what is String in Java and
how to create the String object.
What is String in java
Generally, String is a sequence of characters. But in Java, string is an object that
represents a sequence of characters. The java.lang.String class is used to create a
string object.
How to create a string object?
There are two ways to create String object:
1. By string literal
2. By new keyword
1) String Literal
Java String literal is created by using double quotes. For Example:
String s="welcome";
Each time you create a string literal, the JVM checks the "string constant pool" first. If
the string already exists in the pool, a reference to the pooled instance is returned. If
the string doesn't exist in the pool, a new string instance is created and placed in the
pool. For example:
String s1="Welcome";
String s2="Welcome";//It doesn't create a new instance
⇧
https://www.javatpoint.com/java-string 2/8
Java String
In Java, string is basically an object that represents sequence of char values. An array
of characters works same as Java string. For example:
char[] ch={'j','a','v','a','t','p','o','i','n','t'};
String s=new String(ch);
is same as:
String s="javatpoint";
Java String class provides a lot of methods to perform operations on strings such as
compare(), concat(), equals(), split(), length(), replace(), compareTo(), intern(),
substring() etc.
The java.lang.String class implements Serializable, Comparable and CharSequence
interfaces.
CharSequence Interface
⇧
https://www.javatpoint.com/java-string 1/8
, 5/19/2021 Java String - javatpoint
The CharSequence interface is used to represent the sequence of characters. String,
StringBuffer and StringBuilder classes implement it. It means, we can create strings in
java by using these three classes.
The Java String is immutable which means it cannot be changed. Whenever we change
any string, a new instance is created. For mutable strings, you can use StringBuffer and
StringBuilder classes.
We will discuss immutable string later. Let's first understand what is String in Java and
how to create the String object.
What is String in java
Generally, String is a sequence of characters. But in Java, string is an object that
represents a sequence of characters. The java.lang.String class is used to create a
string object.
How to create a string object?
There are two ways to create String object:
1. By string literal
2. By new keyword
1) String Literal
Java String literal is created by using double quotes. For Example:
String s="welcome";
Each time you create a string literal, the JVM checks the "string constant pool" first. If
the string already exists in the pool, a reference to the pooled instance is returned. If
the string doesn't exist in the pool, a new string instance is created and placed in the
pool. For example:
String s1="Welcome";
String s2="Welcome";//It doesn't create a new instance
⇧
https://www.javatpoint.com/java-string 2/8
