Fixed import to java.util.Arrays, added comments

src/main/java/org/apache/sysml/parser/ParameterizedBuiltinFunctionExpression.java

@@ -20,14 +20,13 @@
 package org.apache.sysml.parser;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 
 import org.apache.sysml.hops.Hop.ParamBuiltinOp;
 import org.apache.sysml.parser.LanguageException.LanguageErrorCodes;
 
-import scala.actors.threadpool.Arrays;
-
 
 public class ParameterizedBuiltinFunctionExpression extends DataIdentifier 
 {

src/main/java/org/apache/sysml/runtime/instructions/cp/ScalarScalarArithmeticCPInstruction.java

@@ -57,6 +57,10 @@ public void processInstruction(ExecutionContext ec) throws DMLRuntimeException{
 			//pre-check (for robustness regarding too long strings)
 			String val1 = so1.getStringValue();
 			String val2 = so2.getStringValue();
+			// This line was commented out because of the addition of 
+			// the built-in function toString.
+			// The toString function adds its own memory estimation
+			// and does not need a hard check on the limit of the size of the string.
 			// StringObject.checkMaxStringLength(val1.length() + val2.length());
 
 			String rval = dop.fn.execute(val1, val2);