[+] implemented the 'shell' UI, [~] Small corrections had to be made in the parser

1 files changed, 6 insertions, 2 deletions

diff --git a/calculator-java/src/main/java/ch/bfh/parser/ExpressionParser.java b/calculator-java/src/main/java/ch/bfh/parser/ExpressionParser.java
index 229e700..f96353e 100644
--- a/calculator-java/src/main/java/ch/bfh/parser/ExpressionParser.java
+++ b/calculator-java/src/main/java/ch/bfh/parser/ExpressionParser.java
@@ -49,6 +49,7 @@ public class ExpressionParser extends Parser {
                 case Token.SUB:
                     if (l != null && op == null) { // if the '-' sign is between two term (op)
                         op = token;
+                        this.ops.add(op);
                         break;
                     } else if (l != null && r != null) { // if we already found a 'l op r' we roll
                         l = r;
@@ -69,7 +70,7 @@ public class ExpressionParser extends Parser {
                     }
                     continue loop;
                 case Token.PAR:
-                    if (lastToken.type == Token.PAL) { // if equal to '(' it means it was created by a Factor
+                    if (lastToken != null && lastToken.type == Token.PAL) { // if equal to '(' it means it was created by a Factor
                         lastToken = token;
                         break loop;
                     } else
@@ -260,7 +261,10 @@ public class ExpressionParser extends Parser {
             @Override
             public double getValue(){
                 if (expression != null)
-                    return expression.getValue();
+                    if (isNegative)
+                        return expression.getValue()*(-1);
+                    else
+                        return expression.getValue();
                 if (isNegative)
                     return value*(-1);
                 return value;