Java String indexOf() Method
Example
Search a string for the first occurrence of "planet":
String myStr = "Hello planet earth, you are a great planet.";
System.out.println(myStr.indexOf("planet"));
Definition and Usage
The indexOf() method returns the position of the first occurrence of specified character(s) in a string.
Tip: Use the lastIndexOf method to return the position of the last occurrence of specified character(s) in a string.
Syntax
There are 4 indexOf() methods:
public int indexOf(String str)
public int indexOf(String str, int fromIndex)
public int indexOf(int char)
public int indexOf(int char, int fromIndex)
Parameter Values
| Parameter | Description | 
|---|---|
| str | A String value, representing the string 
    to search for | 
    
| fromIndex | An int value, representing the index position to start the search from | 
    
| char | An int value, representing a single 
    character, e.g 'A', or a Unicode value | 
    
Technical Details
| Returns: | An int value, representing the index of the first occurrence of the 
  character in the string, or -1 if it never occurs | 
|---|
More Examples
Example
Find the first occurrence of the letter "e" in a string, starting the search at position 5:
public class Main {
  public static void main(String[] args) {
    String myStr = "Hello planet earth, you are a great planet.";
    System.out.println(myStr.indexOf("e", 5));
  }
}
❮ String Methods
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