Replace character in a sentence in java

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COMPLETE SOURCE CODE FOR : ReplaceCharacterInASentence.java
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public class ReplaceCharacterInASentence
{
public static void main(String[]args)
{
 String a="Hellooo Woooorld";

 //REPLACE ALL CHARACTER o WITH a
 String b=a.replace('o','a');
 System.out.println(b);



 //REPLACE A CHARACTER
 //REPLACE LAST o IN Hellooo WITH a

 //IF YOU WANT TO REPLACE A CHARACTER, YOU MUST TAKE WORD
 //THAT CONTAIN THE CHARACTER AND MAKE SURE
 //THE WORD IS ONLY UNIQUE THAT CAN REPRESENT WORD
 //CONTAIN THE CHARACTER
 //This is why we take looo instead of ooo because
 //ooo also exist in Woooorld
 String c=a.replace("looo","looa");
 System.out.println(c);
}
}

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JUST COMPILE AND EXECUTE IT
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