Java Tutorial/Data Type/Extracting String Characters

Beyond the last character of the substring

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String place = "abcedfghijk";
   String segment = place.substring(7, 11);
   System.out.println(segment);
 }

}</source>

hijk

Finding the last occurrence of "a" in the String variable text: the method lastIndexOf()

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String str = "abcdea";
   
   int index = 0;        
   index = str.lastIndexOf("a");         
   System.out.println(index);
 }

}</source>

5

Last index of

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String str = "abcdeabcdef";
  
   int index = 0;        
   index = str.lastIndexOf("ab");         
   System.out.println(index);
 }

}</source>

5

Searching for Substrings

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String str = "abcdeabcdef";
   int startIndex = 3;
   
   int index = 0;        
   index = str.indexOf("ab", startIndex);         
   System.out.println(index);
 }

}</source>

5

Searching Strings for Characters

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String str = "abcde";
   
   int index = 0;        
   index = str.indexOf("c");  
   System.out.println(index);
 }

}</source>

2

String Characters

   <source lang="java">

public class StringCharacters {

 public static void main(String[] args) {
   String text = "To be or not to be?";
   int spaces = 0,
   vowels = 0, 
   letters = 0;
   for (int i = 0; i < text.length(); i++) {
     char ch = Character.toLowerCase(text.charAt(i));
     if (ch == "a" || ch == "e" || ch == "i" || ch == "o" || ch == "u")
       ++vowels;
     if (Character.isLetter(ch))
       ++letters;
     if (Character.isWhitespace(ch))
       ++spaces;
   }
 }

}</source>

To search forwards from a given position: startIndex

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String str = "abcdea";
   int startIndex = 3;
   
   int index = 0;        
   index = str.indexOf("a", startIndex);         
   System.out.println(index);
 }

}</source>

5

Up to the end of the string

   <source lang="java">

public class MainClass{

 public static void main(String[] arg){
   String place = "abcedfghijk";
   String lastWord = place.substring(5);
   System.out.println(lastWord);
 }

}</source>

fghijk