Author: britter
Date: Fri Mar 27 08:03:41 2015
New Revision: 1669520
URL: http://svn.apache.org/r1669520
Log:
Further optimization of LANG-935:
- Avoid toString of the replacement sequence by doing it once.
- Avoid calculating the maximum when not needed.
- Fixup comment for greedy algorithm
Thanks to Fabian Lange.
Modified:
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/text/translate/LookupTranslator.java
Modified:
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/text/translate/LookupTranslator.java
URL:
http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/text/translate/LookupTranslator.java?rev=1669520&r1=1669519&r2=1669520&view=diff
==============================================================================
---
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/text/translate/LookupTranslator.java
(original)
+++
commons/proper/lang/trunk/src/main/java/org/apache/commons/lang3/text/translate/LookupTranslator.java
Fri Mar 27 08:03:41 2015
@@ -29,7 +29,7 @@ import java.util.HashSet;
*/
public class LookupTranslator extends CharSequenceTranslator {
- private final HashMap<String, CharSequence> lookupMap;
+ private final HashMap<String, String> lookupMap;
private final HashSet<Character> prefixSet;
private final int shortest;
private final int longest;
@@ -37,21 +37,20 @@ public class LookupTranslator extends Ch
/**
* Define the lookup table to be used in translation
*
- * Note that, as of Lang 3.1, the key to the lookup table is converted to
a
- * java.lang.String, while the value remains as a java.lang.CharSequence.
- * This is because we need the key to support hashCode and equals(Object),
- * allowing it to be the key for a HashMap. See LANG-882.
+ * Note that, as of Lang 3.1, the key to the lookup table is converted to a
+ * java.lang.String. This is because we need the key to support hashCode
and
+ * equals(Object), allowing it to be the key for a HashMap. See LANG-882.
*
* @param lookup CharSequence[][] table of size [*][2]
*/
public LookupTranslator(final CharSequence[]... lookup) {
- lookupMap = new HashMap<String, CharSequence>();
+ lookupMap = new HashMap<String, String>();
prefixSet = new HashSet<Character>();
int _shortest = Integer.MAX_VALUE;
int _longest = 0;
if (lookup != null) {
for (final CharSequence[] seq : lookup) {
- this.lookupMap.put(seq[0].toString(), seq[1]);
+ this.lookupMap.put(seq[0].toString(), seq[1].toString());
this.prefixSet.add(seq[0].charAt(0));
final int sz = seq[0].length();
if (sz < _shortest) {
@@ -71,24 +70,21 @@ public class LookupTranslator extends Ch
*/
@Override
public int translate(final CharSequence input, final int index, final
Writer out) throws IOException {
- int max = longest;
- if (index + longest > input.length()) {
- max = input.length() - index;
- }
-
- if (!prefixSet.contains(input.charAt(index))) {
- // no translation exists for the input at position index
- return 0;
- }
-
- // descend so as to get a greedy algorithm
- for (int i = max; i >= shortest; i--) {
- final CharSequence subSeq = input.subSequence(index, index + i);
- final CharSequence result = lookupMap.get(subSeq.toString());
-
- if (result != null) {
- out.write(result.toString());
- return i;
+ // check if translation exists for the input at position index
+ if (prefixSet.contains(input.charAt(index))) {
+ int max = longest;
+ if (index + longest > input.length()) {
+ max = input.length() - index;
+ }
+ // implement greedy algorithm by trying maximum match first
+ for (int i = max; i >= shortest; i--) {
+ final CharSequence subSeq = input.subSequence(index, index +
i);
+ final String result = lookupMap.get(subSeq.toString());
+
+ if (result != null) {
+ out.write(result);
+ return i;
+ }
}
}
return 0;
