org.eclipse.core.internal.utils
Class StringPool

java.lang.Object
  org.eclipse.core.internal.utils.StringPool

public final class StringPool
extends java.lang.Object

A string pool is used for sharing strings in a way that eliminates duplicate equal strings. A string pool instance can be maintained over a long period of time, or used as a temporary structure during a string sharing pass over a data structure.

This class is not intended to be subclassed by clients.

Since:

3.1

See Also:

IStringPoolParticipant

Constructor Summary

StringPool()
Creates a new string pool.

Method Summary

java.lang.String	add(java.lang.String string) Adds a String to the pool.
int	getSavedStringCount() Returns an estimate of the size in bytes that was saved by sharing strings in the pool.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StringPool

public StringPool()

Creates a new string pool.

Method Detail

add

public java.lang.String add(java.lang.String string)

Adds a String to the pool. Returns a String that is equal to the argument but that is unique within this pool.

Parameters:

string - The string to add to the pool

Returns:

A string that is equal to the argument.

getSavedStringCount

public int getSavedStringCount()

Returns an estimate of the size in bytes that was saved by sharing strings in the pool. In particular, this returns the size of all strings that were added to the pool after an equal string had already been added. This value can be used to estimate the effectiveness of a string sharing operation, in order to determine if or when it should be performed again. In some cases this does not precisely represent the number of bytes that were saved. For example, say the pool already contains string S1. Now string S2, which is equal to S1 but not identical, is added to the pool five times. This method will return the size of string S2 multiplied by the number of times it was added, even though the actual savings in this case is only the size of a single copy of S2.