minor refactorings

json-path/src/main/java/com/jayway/jsonpath/filter/JsonPathFilterFactory.java

@@ -9,26 +9,30 @@ import java.util.regex.Pattern;
  */
 public class JsonPathFilterFactory {
 
-    private static final Pattern ROOT_FILTER     = Pattern.compile("\\$");
-    private static final Pattern PROPERTY_FILTER = Pattern.compile("\\w+");
-    private static final Pattern WILDCARD_PROPERTY_FILTER = Pattern.compile("\\*");
-    private static final Pattern LIST_FILTER = Pattern.compile("\\[.*?\\]");
-    private static final Pattern TRAVERSE_FILTER = Pattern.compile("\\.\\.");
+    private final static Pattern ROOT_FILTER_PATTERN = Pattern.compile("\\$");
+    private final static Pattern PROPERTY_FILTER_PATTERN = Pattern.compile("\\w+");
+    private final static Pattern WILDCARD_PROPERTY_FILTER_PATTERN = Pattern.compile("\\*");
+    private final static Pattern LIST_FILTER_PATTERN = Pattern.compile("\\[.*?\\]");
+    private final static Pattern TRAVERSE_FILTER_PATTERN = Pattern.compile("\\.\\.");
+
+
+    private final static RootFilter ROOT_FILTER = new RootFilter();
+    private final static TraverseFilter TRAVERSE_FILTER = new TraverseFilter();
 
     public static JsonPathFilterBase createFilter(String pathFragment){
 
 
-        if(ROOT_FILTER.matcher(pathFragment).matches()){
-            return new RootFilter();
+        if(ROOT_FILTER_PATTERN.matcher(pathFragment).matches()){
+            return ROOT_FILTER;
         }
-        else if(PROPERTY_FILTER.matcher(pathFragment).matches() || WILDCARD_PROPERTY_FILTER.matcher(pathFragment).matches() ){
+        else if(PROPERTY_FILTER_PATTERN.matcher(pathFragment).matches() || WILDCARD_PROPERTY_FILTER_PATTERN.matcher(pathFragment).matches() ){
             return new PropertyFilter(pathFragment);
         }
-        else if(LIST_FILTER.matcher(pathFragment).matches()){
+        else if(LIST_FILTER_PATTERN.matcher(pathFragment).matches()){
             return new ListFilter(pathFragment);
         }
-        else if(TRAVERSE_FILTER.matcher(pathFragment).matches()){
-            return new TraverseFilter(pathFragment);
+        else if(TRAVERSE_FILTER_PATTERN.matcher(pathFragment).matches()){
+            return TRAVERSE_FILTER;
         }
 
         return null;

json-path/src/main/java/com/jayway/jsonpath/filter/ListFilter.java

@@ -22,7 +22,7 @@ public class ListFilter extends JsonPathFilterBase {
 
     private static ScriptEngine SCRIPT_ENGINE = new ScriptEngineManager().getEngineByName("js");
 
-    private static final Pattern LIST_INDEX_PATTERN = Pattern.compile("\\[(\\s?\\d+\\s?,?)+\\]");
+    private static final Pattern LIST_INDEX_PATTERN = Pattern.compile("\\[(\\s?\\d+\\s?,?)+\\]"); //[1] OR [1,2,3]
     private static final Pattern LIST_PULL_PATTERN = Pattern.compile("\\[\\s?:(\\d+)\\s?\\]");   //[ :2 ]
     private static final Pattern LIST_WILDCARD_PATTERN = Pattern.compile("\\[\\*\\]");
     private static final Pattern LIST_TAIL_PATTERN_SHORT = Pattern.compile("\\[\\s*-\\s*(\\d+):\\s*\\]");   // [(@.length - 12)] OR [-13:]

json-path/src/main/java/com/jayway/jsonpath/filter/PropertyFilter.java

@@ -12,6 +12,9 @@ import java.util.List;
  * Time: 2:32 PM
  */
 public class PropertyFilter extends JsonPathFilterBase {
+
+    private final static String WILDCARD = "*";
+
     private final String pathFragment;
 
     public PropertyFilter(String pathFragment) {
@@ -20,22 +23,24 @@ public class PropertyFilter extends JsonPathFilterBase {
 
     @Override
     public List<Object> apply(List<Object> filter) {
-        List<Object> result = new JSONArray();
 
-        for (Object current : filter) {
-
-            if ("*".equals(pathFragment)) {
+        List<Object> result = new JSONArray();
 
+        if (WILDCARD.equals(pathFragment)) {
+            for (Object current : filter) {
                 for (Object value : PathUtil.toDocument(current).values()) {
-                     result.add(value);
+                    result.add(value);
                 }
-
-            } else {
+            }
+        }
+        else {
+            for (Object current : filter) {
                 if (PathUtil.toDocument(current).containsKey(pathFragment)) {
                     result.add(PathUtil.toDocument(current).get(pathFragment));
                 }
             }
         }
+
         return result;
     }
 }

json-path/src/main/java/com/jayway/jsonpath/filter/TraverseFilter.java

@@ -12,11 +12,6 @@ import java.util.List;
  * Time: 2:33 PM
  */
 public class TraverseFilter extends JsonPathFilterBase {
-    private final String pathFragment;
-
-    public TraverseFilter(String pathFragment) {
-        this.pathFragment = pathFragment;
-    }
 
     @Override
     public List<Object> apply(List<Object> filter) {