trimming : Java Glossary


To remove unwanted waste from the beginning or end of something. In addition to the built-in Java trimming methods, I have written a some myself and posted them as part of the com.mindprod.common18.ST class that you can download including source.
Java Trimming Methods
Method Function
ArrayList.trimToSize chops off the unused RAM (Random Access Memory) on ArrayList’s internal array by allocating a new array just the right size and copying the elements over, then discarding the old internal array to be garbage collected.
Collection.toArray Exports an array just the right size. Always provide it with a template array the right size and type e.g.
String.trim removes both leading and trailing whitespace (not just blanks, nul, \n, \t…all the chars in the range 0..0x20) and gives you a new substring of the orginal. trim is neatly implmented. If there is nothing to trim, it just gives you your original String back. If there is something to trim, it gives you a substring view of your original immutable String. It does not need to allocate a new internal char[] or copy over the meat characters. In other words trim is a fast operation.
ST.condense collapses multiple spaces to a single space and trims off both leading and trailing spaces (not whitespace).
ST.countLeading count how many of a leading character there are, e.g. how many spaces or '*'s.
ST.countTrailing counts how many of a trailing character there are, e.g. how many spaces or '*'s.
ST.squish removes all spaces (not whitespace), included embedded ones.
ST.trimLeading removes just leading whitespace.
ST.trimTrailing removes just trailing whitespace.

Learning More

Oracle’s Javadoc on ArrayList.trimHtoSize : available:
Oracle’s Javadoc on String.trim : available:

This page is posted
on the web at:

Optional Replicator mirror
on local hard disk J:

Please the feedback from other visitors, or your own feedback about the site.
Contact Roedy. Please feel free to link to this page without explicit permission.

Your face IP:[]
You are visitor number