如何避免字符串重复

Question

I have two different string String A="example"; String B="example"; string String A="example"; String B="example"; if concat both the string i am getting examplexample. Is there any possibility to avoid repetition of string with same name..??

Answer 1

How about this ?

if(!a.equals(b)){// or if needed use contains() , equalIgnoreCase() depending on your need
 //concat
}

Answer 2

The Strings are not different , the same String object is assigned to two different variables ("two pointers to the same memory address").

Consider dumping all strings to a Set before concatenating, this avoids duplicates in the concatenated sequence:

Set<String> strings = new HashSet<String>();
StringBuilder resultBuilder = new StringBuilder();
for (String s:getAllStrings()) {  // some magic to get all your strings
   if (strings.contains(s))
       continue;                  // has been added already
   resultBuilder.append(s);       // concatenate
   strings.add(s);                // put string to set
}
String result = resultBuilder.toString();

Answer 3

Just create a Set (It has mathematics set behaviour, it won't accept the duplicate objects)

Set<String> strings = new HashSet<String>();

//Fill this set with all the String objects

strings.add(A)
Strings.add(B)

//Now iterate this set and create a String Object

StringBuilder resultBuilder = new StringBuilder();

for(String string:Strings){
resultBuilder.append(string);
}
return resultBuilder.toString()

`

Answer 4

You can. Try something like this

private String concatStringExample1(String firstString, String secondString) {
            if(firstString.equalsIgnoreCase(secondString)) { // String matched
                 return firstString;  // or return secondString
            } else { // Not matched
                return firstString.concat(secondString); 
            }
        }

or

private String concatStringExample2(String firstString, String secondString) {
            if(firstString != null && firstString != null ) {
                if(firstString.toLowerCase().indexOf(secondString.toLowerCase()) >= 0)
                    return firstString;
                else if(secondString.toLowerCase().indexOf(firstString.toLowerCase()) >= 0)
                    return secondString;
                else
                    return firstString.concat(secondString);
            } else {
                return "";
            }
        }