Strings

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Strings in Java are objects that can hold a sequence of characters contained within a pair of double quotes ("). It is not a primitive data type.

Strings can either be compared by value via method (e.g., .equals()) or by reference, or location in memory, (e.g., ==) via operator.

Example

Java strings provide a way to store text such as words, sentences, or whole paragraphs. They can be any length and may contain letters, numbers, symbols, and spaces:

import java.util.*;

class StringExample {
  public static void main(String[] args) {
    // Using a string literal
    System.out.println("Codecademy");

    // Creating a String variable
    String address = "575 Broadway #5, New York, NY 10012";
    System.out.println(address);
  }
}

This will output the following:

Codecademy
575 Broadway #5, New York, NY 10012

Strings

.charAt(): Returns the character at the given index in the string.
.codePointAt(): Returns the Unicode value at the given index in the string.
.codePointBefore(): Returns the Unicode value before the given index in the string.
.codePointCount(): Returns the number of Unicode values in specified range of a string.
.compareTo(): Returns 0 if two strings are equal in Unicode value. Otherwise, the lexicographical difference is returned.
.compareToIgnoreCase(): Returns 0 if two strings are equal in Unicode value, regardless of character case. Otherwise, the lexicographical difference is returned.
.concat(): Returns a string that is the concatenation of the given strings.
.contains(): Returns true if a sequence of characters exists in a given string, otherwise false.
.contentEquals(): Returns true if the sequence of characters in the string is equal to the content of the specified string. If not, returns false.
.copyValueOf(): Returns a string with characters copied from an array.
.equals(): Returns true if two strings are equal in value and false otherwise.
.format(): Returns a string with additional arguments in a specifically defined format.
.indexOf(): Returns the zero-indexed position of the first occurrence of the given character(s) in a string.
.length(): Returns the number of characters contained in a string.
.replace(): Returns a new string where all instances of a given value are switched with a new value.
.split(): Splits a string into an array of substrings based on a delimiter pattern.
.valueOf(): Returns the string representation of a given value.