add-decode-function

jolt-core/src/main/java/com/bazaarvoice/jolt/Modifier.java

@@ -44,6 +44,7 @@ public abstract class Modifier implements SpecDriven, ContextualTransform {
         STOCK_FUNCTIONS.put( "toLower", new Strings.toLowerCase() );
         STOCK_FUNCTIONS.put( "toUpper", new Strings.toUpperCase() );
         STOCK_FUNCTIONS.put( "concat", new Strings.concat() );
+        STOCK_FUNCTIONS.put( "decode", new Strings.decode() );
         STOCK_FUNCTIONS.put( "join", new Strings.join() );
         STOCK_FUNCTIONS.put( "split", new Strings.split() );
         STOCK_FUNCTIONS.put( "substring", new Strings.substring() );

jolt-core/src/main/java/com/bazaarvoice/jolt/modifier/function/Function.java

@@ -64,13 +64,15 @@
  *      toLower     - returns toLower value of toString() value of first arg, rest is ignored
  *      toUpper     - returns toUpper value of toString() value of first arg, rest is ignored
  *      concat      - concatenate all given arguments' toString() values
+ *      decode      - decode all given arguments' values similar to a SQL decode
  *
  *      min       - returns the min of all numbers provided in the arguments, non-numbers are ignored
  *      max       - returns the max of all numbers provided in the arguments, non-numbers are ignored
  *      abs         - returns the absolute value of first argument, rest is ignored
  *      toInteger   - returns the intValue() value of first argument if its numeric, rest is ignored
  *      toDouble    - returns the doubleValue() value of first argument if its numeric, rest is ignored
  *      toLong      - returns the longValue() value of first argument if its numeric, rest is ignored
+ *      toBoolean   - returns the booleanValue() value of first argument if its boolean, rest is ignored
  *
  * All of these functions returns Optional.EMPTY if unsuccessful, which results in a no-op when performing
  * the actual write in the json doc.

jolt-core/src/main/java/com/bazaarvoice/jolt/modifier/function/Strings.java

@@ -78,6 +78,28 @@ protected Optional<Object> applyList( final List<Object> argList ) {
         }
     }
 
+    public static final class decode extends Function.ListFunction {
+	@Override
+	protected Optional<Object> applyList(final List<Object> argList) {
+	    if (argList.size() > 0) {
+		Object value = argList.get(0);
+		for (int index = 1; index < argList.size() - 1; index += 2) {
+		    Object test = argList.get(index);
+		    if (java.util.Objects.equals(value, test)) {
+			Object result = argList.get(index + 1);
+			return Optional.of(result);
+		    }
+		}
+		// default
+		if (argList.size() % 2 == 0) {
+		    Object result = argList.get(argList.size() - 1);
+		    return Optional.of(result);
+		}
+	    }
+	    return Optional.of(null);
+	}
+    }
+
     public static final class substring extends Function.ListFunction {
 
         @Override

jolt-core/src/test/resources/json/modifier/functions/stringsTests.json

@@ -26,6 +26,11 @@
             "basic": "=concat(@(2,lower.leading) , ' ' , @(2,lower.trailing))",
             "parens": "=concat(@(2,lower.leading) , ' (', @(2,lower.trailing), ')')"
         },
+        "decode": {
+            "decodeTrue": "=decode('1' , '1' , 'true', '0', 'false')",
+            "decodeFalse": "=decode('0' , '1' , 'true', '0', 'false')",
+            "decodeDefault": "=decode('0' , '1' , 'true', 'false')"
+        },        
         "substring": {
             "basic1": "=substring(@(2,string), 0, 9)",
             "basic2": "=substring(@(2,string), 4, 9)",
@@ -83,6 +88,11 @@
             "basic": "the quick brown fox jumped over the lazy dog",
             "parens": "the quick brown fox (jumped over the lazy dog)"
         },
+        "decode": {
+            "decodeTrue": "true",
+            "decodeFalse": "false",
+            "decodeDefault": "false"
+        },        
         "substring": {
             "basic1": "the QuIcK",
             "basic2": "QuIcK",