How to remove the unused positional Parameters from String format

Question

I have a pattern like :

String pattern = "{0},{1},{2},{3},{4},{5},{6},{7}";

I have a Array of values to get Populated in this pattern:

Object[] values = new String[8];

This Array of values is dynamic , sometimes it gets populated with full 8 allotted slots and some times it is less than that, but never more than allotted size.

Now when it is less than 8 slots(eg), and when i format it using

MessageFormat messageFormat = new MessageFormat(pattern);
header = new StringBuffer();
messageFormat.format(values, header, null);

theirs remains those position whose substitutes are not found:

eg:

    String pattern = "{0},{1},{2},{3},{4}";
    Object[] values = {"abc", "cde", "gef"};
    MessageFormat messageFormat = new MessageFormat(pattern);
    StringBuffer header = new StringBuffer();
    System.out.println(messageFormat.format(values, header, null));

output

abc,cde,gef,{3},{4}

But what I want is those position should also be moved: As final output should be like this:

abc, cde, gef

Answer 1

String pattern = "{0},{1},{2},{3},{4}";
String[] patternArray = pattern.split("}");
Object[] values = {"abc", "cde", "gef"};
StringBuilder patternBuilder = new StringBuilder();
for(int i = 0; i < values.length; ++i){
  patternBuilder.append(patternArray[i]).append("}");
}
pattern = patternBuilder.toString();
MessageFormat messageFormat = new MessageFormat(pattern);
StringBuffer header = new StringBuffer();
System.out.println(messageFormat.format(values, header, null));