trimming : Java Glossary

trimming

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.common11.StringTools 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.
StringTools.condense	collapses multiple spaces to a single space and trims off both leading and trailing spaces (not whitespace).
StringTools.countLeading	count how many of a leading character there are, e.g. how many spaces or '*'s.
StringTools.countTrailing	counts how many of a trailing character there are, e.g. how many spaces or '*'s.
StringTools.squish	removes all spaces (not whitespace), included embedded ones.
StringTools.trimLeading	removes just leading whitespace.
StringTools.trimTrailing	removes just trailing whitespace.

Learning More

Oracle’s Javadoc on ArrayList.trimHtoSize : available:

on the web at Oracle.com
in the current JDK 1.7.0_04 or in the old JDK 1.6.0_32 on your local Windows J: drive.

Oracle’s Javadoc on String.trim : available:

on the web at Oracle.com
in the current JDK 1.7.0_04 or in the old JDK 1.6.0_32 on your local Windows J: drive.

ArrayList
Collections
com.mindprod.common11 : download package containing StringTools
removing elements from ArrayLists
String
trimming ArrayLists

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