In my TheInput string, I want to replace space by '-', period by '.', new line by '!', and end-of-message by '+' before

[answerhappygod]

In my TheInput string, I want to replace space by
'-', period by '.', new line by '!', and end-of-message by '+'
before loading it in the frequency table.
import java.util.HashMap;
import java.util.Map;
public class HuffmanFrequencyTable {
/**
* the map for recording the key and the
frequency.
*/
private Map<Character, Integer> HuffColl;
/**
* constructor of the freq table
* @param theInput the input string
*/
public HuffmanFrequencyTable(String theInput){
HuffColl = new HashMap<Character,
Integer>();
checkandadd(theInput);
}
/**
* add each character into the freq table
* @param theInput
*/
private final void checkandadd(String theInput)
{

if(theInput.length() < 2)
{
System.out.println("Length
of input is less than 2.");
}
else
{
for(int i = 0; i <
theInput.length(); i++)
{

theInput.replace(' ', '-');

theInput.replace('.', '+');
char temp =
theInput.charAt(i);

if(HuffColl.containsKey(theInput.charAt(i)))
{

HuffColl.put(temp, HuffColl.get(temp) + 1);

}

else
{

HuffColl.put(temp, 1);
}

}
}
}
/**
* return the map object recording the table.
* @return the map represents the table.
*/
public Map<Character, Integer> getTable(){
return HuffColl;
}
}