com.sun.enterprise.cli.framework.StringEditDistance Maven / Gradle / Ivy
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package com.sun.enterprise.cli.framework;
public class StringEditDistance
{
/**
* Computes the edit distance between two strings.
*
*
* The complexity is O(nm) where n=a.length() and m=b.length().
*/
public static int editDistance( String a, String b )
{
return new StringEditDistance(a,b).calc();
}
/**
* Finds the string in the group closest to
* key and returns it.
*
* @return null if group.length==0.
*/
public static String findNearest( String key, String[] group )
{
int c = Integer.MAX_VALUE;
String r = null;
for( int i=0; ied ) {
c = ed;
r = group[i];
}
}
return r;
}
/** cost vector. */
private int[] cost;
/** back buffer. */
private int[] back;
/** Two strings to be compared. */
private final String a,b;
private StringEditDistance( String a, String b ) {
this.a=a;
this.b=b;
cost = new int[a.length()+1];
back = new int[a.length()+1];
// back buffer
for( int i=0; i<=a.length(); i++ )
cost[i] = i;
}
/**
* Swaps two buffers.
*/
private void flip() {
int[] t = cost;
cost = back;
back = t;
}
private int min(int a,int b,int c) {
return Math.min(a,Math.min(b,c));
}
private int calc() {
for( int j=0; j