* do some calculations once in the constructor instead of for every evaluation of the filter

* make ArrayEvalFilter.ConditionStatement and PathTokenFilter static

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

@@ -29,16 +29,11 @@ import java.util.regex.Pattern;
 public class ArrayEvalFilter extends PathTokenFilter {
 
     private static final Pattern PATTERN = Pattern.compile("(.*?)\\s?([=<>]+)\\s?(.*)");
+    private final ConditionStatement conditionStatement;
 
     public ArrayEvalFilter(String condition) {
         super(condition);
-    }
-
-    @Override
-    public Object filter(Object obj, JsonProvider jsonProvider) {
         //[?(@.isbn == 10)]
-        List<Object> src = jsonProvider.toList(obj);
-        List<Object> result = jsonProvider.createList();
 
         String trimmedCondition = condition;
 
@@ -49,7 +44,13 @@ public class ArrayEvalFilter extends PathTokenFilter {
 
         trimmedCondition = trim(trimmedCondition, 5, 2);
 
-        ConditionStatement conditionStatement = createConditionStatement(trimmedCondition);
+        this.conditionStatement = createConditionStatement(trimmedCondition);
+    }
+
+    @Override
+    public Object filter(Object obj, JsonProvider jsonProvider) {
+        List<Object> src = jsonProvider.toList(obj);
+        List<Object> result = jsonProvider.createList();
 
         for (Object item : src) {
             if (isMatch(item, conditionStatement, jsonProvider)) {
@@ -101,18 +102,20 @@ public class ArrayEvalFilter extends PathTokenFilter {
         }
     }
 
-    private class ConditionStatement {
+    private static class ConditionStatement {
         private final String field;
         private final String operator;
-        private String expected;
+        private final String expected;
 
         private ConditionStatement(String field, String operator, String expected) {
             this.field = field;
             this.operator = operator.trim();
-            this.expected = expected;
+            
 
-            if(this.expected.startsWith("'")){
-                this.expected = trim(this.expected, 1, 1);
+            if(expected.startsWith("'")){
+                this.expected = trim(expected, 1, 1);
+            }else{
+                this.expected = expected;
             }
         }
 

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

@@ -25,9 +25,22 @@ import java.util.regex.Pattern;
 public class ArrayIndexFilter extends PathTokenFilter {
 
     private static final Pattern SINGLE_ARRAY_INDEX_PATTERN = Pattern.compile("\\[\\d+\\]");
+    private static final Pattern COMMA = Pattern.compile(",");
+    private static final Pattern SPACE = Pattern.compile(" ");
+
+    
+    private final String trimmedCondition;
     
     public ArrayIndexFilter(String condition) {
         super(condition);
+        String trimmedCondition = trim(condition, 1, 1);
+
+        if(trimmedCondition.contains("@.length")){
+            trimmedCondition = trim(trimmedCondition, 1, 1);
+            trimmedCondition = trimmedCondition.replace("@.length", "");
+            trimmedCondition = trimmedCondition + ":";
+        }
+        this.trimmedCondition = trimmedCondition;
     }
 
     @Override
@@ -36,17 +49,11 @@ public class ArrayIndexFilter extends PathTokenFilter {
         List<Object> src = jsonProvider.toList(obj);
         List<Object> result = jsonProvider.createList();
 
-        String trimmedCondition = trim(condition, 1, 1);
-
-        if(trimmedCondition.contains("@.length")){
-            trimmedCondition = trim(trimmedCondition, 1, 1);
-            trimmedCondition = trimmedCondition.replace("@.length", "");
-            trimmedCondition = trimmedCondition + ":";
-        }
+        
 
 
         if (trimmedCondition.startsWith(":")) {
-            trimmedCondition = trim(trimmedCondition, 1, 0);
+            String trimmedCondition = trim(this.trimmedCondition, 1, 0);
             int get = Integer.parseInt(trimmedCondition);
             for (int i = 0; i < get; i++) {
                 result.add(src.get(i));
@@ -54,12 +61,12 @@ public class ArrayIndexFilter extends PathTokenFilter {
             return result;
 
         } else if (trimmedCondition.endsWith(":")) {
-            trimmedCondition = trim(trimmedCondition.replace(" ", ""), 1, 1);
+            String trimmedCondition = trim(SPACE.matcher(this.trimmedCondition).replaceAll(""), 1, 1);
             int get = Integer.parseInt(trimmedCondition);
             return src.get(src.size() - get);
 
         } else {
-            String[] indexArr = trimmedCondition.split(",");
+            String[] indexArr = COMMA.split(trimmedCondition);
 
             if(src.isEmpty()){
                 return result;

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

@@ -27,8 +27,11 @@ import java.util.Map;
  */
 public class FieldFilter extends PathTokenFilter {
 
+    private final String[] split;
+
     public FieldFilter(String condition) {
         super(condition);
+        this.split = condition.split("','");
     }
 
     @Override
@@ -43,7 +46,7 @@ public class FieldFilter extends PathTokenFilter {
 
                         Map<String, Object> map = jsonProvider.toMap(current);
 
-                        String[] split = condition.split("','");
+                        
                         if(split.length == 1){
                             if (map.containsKey(condition)) {
                                 Object o = map.get(condition);
@@ -67,7 +70,6 @@ public class FieldFilter extends PathTokenFilter {
                 return result;
             }
         } else {
-            String[] split = condition.split("','");
 
             Map<String, Object> map = jsonProvider.toMap(obj);
             if(!map.containsKey(condition) && split.length == 1){

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

@@ -24,8 +24,18 @@ import java.util.Map;
  */
 public class HasFieldFilter extends PathTokenFilter {
 
+    private final String trimmedCondition;
+
     public HasFieldFilter(String condition) {
         super(condition);
+        String trimmedCondition = condition;
+
+        if(condition.contains("['")){
+            trimmedCondition = trimmedCondition.replace("['", ".");
+            trimmedCondition = trimmedCondition.replace("']", "");
+        }
+
+        this.trimmedCondition = trim(trimmedCondition, 5, 2);
     }
 
     @Override
@@ -35,15 +45,6 @@ public class HasFieldFilter extends PathTokenFilter {
         List<Object> src = jsonProvider.toList(obj);
         List<Object> result = jsonProvider.createList();
 
-        String trimmedCondition = condition;
-
-        if(condition.contains("['")){
-            trimmedCondition = trimmedCondition.replace("['", ".");
-            trimmedCondition = trimmedCondition.replace("']", "");
-        }
-
-        trimmedCondition = trim(trimmedCondition, 5, 2);
-
         for (Object item : src) {
             if(jsonProvider.isMap(item)){
                 Map<String, Object> map = jsonProvider.toMap(item);

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

@@ -34,7 +34,7 @@ public abstract class PathTokenFilter {
         return condition;
     }
 
-    String trim(String str, int front, int end) {
+    static String trim(String str, int front, int end) {
         String res = str;
 
         if (front > 0) {