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In this core java programming tutorial we will Write a program to find out substring in given string in java.
Write a program to find out substring in given string.
Example in java>
abctigeraCd contains tiger at index 3
tigeraCd contains tiger at index 0
tigraCd doesn’t contains tiger.
Full Program/SourceCode/ Example - find out substring in given string in java >
/** Copyright (c), AnkitMittal JavaMadeSoEasy.com */
public class FindSubString {
public static void main(String[] args) {
String inputString;
String searchSubString;
int foundIndex; //index at which subString is found by our method.
int javaApiFoundIndex; //index at which subString is found by JAVA API's indexOf() method.
inputString="abctigeraCd";
searchSubString="tiger";
System.out.println("TEST1");
foundIndex=isSubString(inputString,searchSubString);
System.out.println(foundIndex>-1 ? inputString+ " contains "+searchSubString + " at index " +foundIndex : inputString+ "doesn't contains "+searchSubString);
javaApiFoundIndex=inputString.indexOf("tiger");
System.out.print("Java API's indexOf() method says> ");
System.out.println(javaApiFoundIndex>-1 ? inputString+ " contains "+searchSubString + " at index " +javaApiFoundIndex : inputString+ "doesn't contains "+searchSubString);
inputString="tigeraCd";
searchSubString="tiger";
System.out.println("\nTEST2");
foundIndex=isSubString(inputString,searchSubString);
System.out.println(foundIndex>-1 ? inputString+ " contains "+searchSubString + " at index " +foundIndex : inputString+ "doesn't contains "+searchSubString);
javaApiFoundIndex=inputString.indexOf("tiger");
System.out.print("Java API's indexOf() method says> ");
System.out.println(javaApiFoundIndex>-1 ? inputString+ " contains "+searchSubString + " at index " +javaApiFoundIndex : inputString+ "doesn't contains "+searchSubString);
}
/**
* Below method returns subString index in given inputString.
* Returns -1 if subString is not found.
*/
public static int isSubString(String inputString, String searchSubString){
char inputStringAr[]=inputString.toCharArray();
char searchSubStringAr[]=searchSubString.toCharArray();
int count=0; //if count matches searchSubStringAr length,than string is found in string
for(int i=0;i<inputStringAr.length;i++){
if( String.valueOf(inputStringAr[i]).equals(String.valueOf(searchSubStringAr[count]))){
count++; //index of searchSubStringAr
if(count==searchSubStringAr.length){
return i-count+1; //substring found, return starting index of
}
}
else{
/*
*Below if condition comes into role, when some part of searchSubString is present before whole searchSubString.
Eg= searchSubString=tiger & inputString="tigtiger" [here, (tig) is present before (tiger)]
*/
if(count>0){
count=0;
i--;
}
}
}
return -1; //substring not found.
}
}
/*OUTPUT
TEST1
abctigeraCd contains tiger at index 3
Java API's indexOf() method says> abctigeraCd contains tiger at index 3
TEST2
tigeraCd contains tiger at index 0
Java API's indexOf() method says> tigeraCd contains tiger at index 0
*/
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So in this core java programming tutorial we Wrote a program how to find out substring in given string in java.
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