Find word from string java

Looking back at the original question, we need to find some given keywords in a given sentence, count the number of occurrences and know something about where. I don’t quite understand what «where» means (is it an index in the sentence?), so I’ll pass that one… I’m still learning java, one step at a time, so I’ll see to that one in due time

It must be noticed that common sentences (as the one in the original question) can have repeated keywords, therefore the search cannot just ask if a given keyword «exists or not» and count it as 1 if it does exist. There can be more then one of the same. For example:

// Base sentence (added punctuation, to make it more interesting):
String sentence = "Say that 123 of us will come by and meet you, "
                + "say, at the woods of 123woods.";

// Split it (punctuation taken in consideration, as well):
java.util.List<String> strings = 
                       java.util.Arrays.asList(sentence.split(" |,|\."));

// My keywords:
java.util.ArrayList<String> keywords = new java.util.ArrayList<>();
keywords.add("123woods");
keywords.add("come");
keywords.add("you");
keywords.add("say");

By looking at it, the expected result would be 5 for «Say» + «come» + «you» + «say» + «123woods», counting «say» twice if we go lowercase. If we don’t, then the count should be 4, «Say» being excluded and «say» included. Fine. My suggestion is:

// Set... ready...?
int counter = 0;

// Go!
for(String s : strings)
{
    // Asking if the sentence exists in the keywords, not the other
    // around, to find repeated keywords in the sentence.
    Boolean found = keywords.contains(s.toLowerCase());
    if(found)
    {
        counter ++;
        System.out.println("Found: " + s);
    }
}

// Statistics:
if (counter > 0)
{
    System.out.println("In sentence: " + sentence + "n"
                     + "Count: " + counter);
}

And the results are:

Found: Say
Found: come
Found: you
Found: say
Found: 123woods
In sentence: Say that 123 of us will come by and meet you, say, at the woods of 123woods.
Count: 5

Java Program to Search Word in a String

In java programming, indexOf method is used to find the index of sub string in the string.

indexOf method returns index if sub string is found in the string, otherwise returns -1.

This java program is used to check whether word or substring is found in the string or not.

Here string and word are both user inputs.

indexOf method is used to search the word in string from left to right.

import java.util.Scanner;

public class SearchString {
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		System.out.println("Search word in string"); 
		System.out.println("-----------------------"); 
		System.out.print("Enter String: "); 
		String str = sc.nextLine();
		System.out.print("Enter word to search: ");
		String word =sc.next();
		
		int index = str.indexOf(word); 
		if(index >= 0){
			System.out.print("Search Found index: ");
			System.out.println(index);
		} else {
			System.out.println("No Search Found!");
		}	
	}
}

Output:

D:Java_Programs>javac SearchString.java
D:Java_Programs>java SearchString 
Search word in string
----------------------
Enter String: This is testing in progress
Enter word to search: testing
Search Found index: 8

D:Java_Programs>javac SearchString.java
D:Java_Programs>java SearchString 
Search word in string
---------------------
Enter String: This is testing in progress
Enter word to search: searching
No Search Found!

Java Program to Search Word in a String from Right to Left

lastIndexOf method returns index if sub string is found in the string and matches from end to beginning of the string, otherwise returns -1.

import java.util.Scanner;

public class SearchString {
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		System.out.println("Search word in string from right to left"); 
		System.out.println("------------------------------------------"); 
		System.out.print("Enter String: "); 
		String str = sc.nextLine();
		System.out.print("Enter word to search: ");
		String word =sc.next();
		
		int index = str.lastIndexOf(word); 
		if(index >= 0){
			System.out.print("Search Found index: ");
			System.out.println(index);
		} else {
			System.out.println("No Search Found!");
		}	
	}
}

Output:

D:Java_Programs>javac SearchString.java
D:Java_Programs>java SearchString 
Search word in string from right to left
------------------------------------------
Enter String: This is testing codingpointer.com and is to identify issues!
Enter word to search: is
Search Found index: 53

D:Java_Programs>javac SearchString.java
D:Java_Programs>java SearchString 
Search word in string from right to left
------------------------------------------
Enter String: This is testing in progress
Enter word to search: searching
No Search Found!

Problem Description

How to search a word inside a string?

Solution

This example shows how we can search a word within a String object using indexOf() method which returns a position index of a word within the string if found. Otherwise it returns -1.

public class SearchStringEmp{
   public static void main(String[] args) {
      String strOrig = "Hello readers";
      int intIndex = strOrig.indexOf("Hello");
      
      if(intIndex == - 1) {
         System.out.println("Hello not found");
      } else {
         System.out.println("Found Hello at index " + intIndex);
      }
   }
}

Result

The above code sample will produce the following result.

Found Hello at index 0

This example shows how we can search a word within a String object

public class HelloWorld {
   public static void main(String[] args) {
      String text = "The cat is on the table";
      System.out.print(text.contains("the"));
   }
}

Result

The above code sample will produce the following result.

true

java_strings.htm