DATAMONGO-1290 - Polishing.

Removed a level of indentation from ExpressionEvaluationParameterBinder.replacePlaceholders(…). Polished JavaDoc.

Original pull request: #332.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/repository/query/ExpressionEvaluatingParameterBinder.java

@@ -38,6 +38,7 @@ import com.mongodb.util.JSON;
  * 
  * @author Christoph Strobl
  * @author Thomas Darimont
+ * @author Oliver Gierke
  * @since 1.9
  */
 class ExpressionEvaluatingParameterBinder {
@@ -62,13 +63,13 @@ class ExpressionEvaluatingParameterBinder {
 	}
 
 	/**
-	 * Bind values provided by {@link MongoParameterAccessor} to placeholders in {@literal raw} while consisdering
+	 * Bind values provided by {@link MongoParameterAccessor} to placeholders in {@literal raw} while considering
 	 * potential conversions and parameter types.
 	 * 
-	 * @param raw
-	 * @param accessor
-	 * @param bindingContext
-	 * @return {@literal null} if given {@literal raw} value is empty.
+	 * @param raw can be {@literal null} or empty.
+	 * @param accessor must not be {@literal null}.
+	 * @param bindingContext must not be {@literal null}.
+	 * @return {@literal null} if given {@code raw} value is empty.
 	 */
 	public String bind(String raw, MongoParameterAccessor accessor, BindingContext bindingContext) {
 
@@ -80,12 +81,11 @@ class ExpressionEvaluatingParameterBinder {
 	}
 
 	/**
-	 * Replaced the parameter place-holders with the actual parameter values from the given {@link ParameterBinding}s.
+	 * Replaced the parameter placeholders with the actual parameter values from the given {@link ParameterBinding}s.
 	 * 
-	 * @param input
-	 * @param accessor
-	 * @param parameters
-	 * @param bindings
+	 * @param input must not be {@literal null} or empty.
+	 * @param accessor must not be {@literal null}.
+	 * @param bindings must not be {@literal null}.
 	 * @return
 	 */
 	private String replacePlaceholders(String input, MongoParameterAccessor accessor, BindingContext bindingContext) {
@@ -95,7 +95,6 @@ class ExpressionEvaluatingParameterBinder {
 		}
 
 		boolean isCompletlyParameterizedQuery = input.matches("^\\?\\d+$");
-
 		StringBuilder result = new StringBuilder(input);
 
 		for (ParameterBinding binding : bindingContext.getBindings()) {
@@ -103,32 +102,31 @@ class ExpressionEvaluatingParameterBinder {
 			String parameter = binding.getParameter();
 			int idx = result.indexOf(parameter);
 
-			if (idx != -1) {
-				String valueForBinding = getParameterValueForBinding(accessor, bindingContext.getParameters(), binding);
+			if (idx == -1) {
+				continue;
+			}
 
-				// if the value to bind is an object literal we need to remove the quoting around
-				// the expression insertion point.
-				boolean shouldPotentiallyRemoveQuotes = valueForBinding.startsWith("{") && !isCompletlyParameterizedQuery;
+			String valueForBinding = getParameterValueForBinding(accessor, bindingContext.getParameters(), binding);
 
-				int start = idx;
-				int end = idx + parameter.length();
+			int start = idx;
+			int end = idx + parameter.length();
 
-				if (shouldPotentiallyRemoveQuotes) {
+			// If the value to bind is an object literal we need to remove the quoting around the expression insertion point.
+			if (valueForBinding.startsWith("{") && !isCompletlyParameterizedQuery) {
 
-					// is the insertion point actually surrounded by quotes?
-					char beforeStart = result.charAt(start - 1);
-					char afterEnd = result.charAt(end);
+				// Is the insertion point actually surrounded by quotes?
+				char beforeStart = result.charAt(start - 1);
+				char afterEnd = result.charAt(end);
 
-					if ((beforeStart == '\'' || beforeStart == '"') && (afterEnd == '\'' || afterEnd == '"')) {
+				if ((beforeStart == '\'' || beforeStart == '"') && (afterEnd == '\'' || afterEnd == '"')) {
 
-						// skip preceeding and following quote
-						start -= 1;
-						end += 1;
-					}
+					// Skip preceding and following quote
+					start -= 1;
+					end += 1;
 				}
-
-				result.replace(start, end, valueForBinding);
 			}
+
+			result.replace(start, end, valueForBinding);
 		}
 
 		return result.toString();
@@ -137,16 +135,17 @@ class ExpressionEvaluatingParameterBinder {
 	/**
 	 * Returns the serialized value to be used for the given {@link ParameterBinding}.
 	 * 
-	 * @param accessor
+	 * @param accessor must not be {@literal null}.
 	 * @param parameters
-	 * @param binding
+	 * @param binding must not be {@literal null}.
 	 * @return
 	 */
 	private String getParameterValueForBinding(MongoParameterAccessor accessor, MongoParameters parameters,
 			ParameterBinding binding) {
 
-		Object value = binding.isExpression() ? evaluateExpression(binding.getExpression(), parameters,
-				accessor.getValues()) : accessor.getBindableValue(binding.getParameterIndex());
+		Object value = binding.isExpression()
+				? evaluateExpression(binding.getExpression(), parameters, accessor.getValues())
+				: accessor.getBindableValue(binding.getParameterIndex());
 
 		if (value instanceof String && binding.isQuoted()) {
 			return (String) value;
@@ -155,9 +154,11 @@ class ExpressionEvaluatingParameterBinder {
 		if (value instanceof byte[]) {
 
 			String base64representation = DatatypeConverter.printBase64Binary((byte[]) value);
+
 			if (!binding.isQuoted()) {
 				return "{ '$binary' : '" + base64representation + "', '$type' : " + BSON.B_GENERAL + "}";
 			}
+
 			return base64representation;
 		}
 
@@ -167,9 +168,9 @@ class ExpressionEvaluatingParameterBinder {
 	/**
 	 * Evaluates the given {@code expressionString}.
 	 * 
-	 * @param expressionString
-	 * @param parameters
-	 * @param parameterValues
+	 * @param expressionString must not be {@literal null} or empty.
+	 * @param parameters must not be {@literal null}.
+	 * @param parameterValues must not be {@literal null}.
 	 * @return
 	 */
 	private Object evaluateExpression(String expressionString, MongoParameters parameters, Object[] parameterValues) {