fix little stuff in Literal Node

AST.py

@@ -55,6 +55,7 @@ class ASTNode():
         pass
 
     def checkType(self):
+        # self is type correct if all its children are type correct (no exception raised)
         for c in self.children:
             if c and hasattr(c, 'checkType'):
                 c.checkType()

UnitNodes.py

@@ -10,9 +10,9 @@ from TheTypeNode import TypeNode
 # literals
 class LiteralNode(ASTNode):
     toLiType = dict({
-        'LITERALBOOL': 'bool',
+        'LITERALBOOL': 'boolean',
         'LITERALCHAR': 'char',
-        'LITERALSTRING': 'String',
+        'LITERALSTRING': 'java.lang.String',
         'NULL': 'null',
         'NUM': 'int',
         'ZERO': 'int'
@@ -20,14 +20,14 @@ class LiteralNode(ASTNode):
     # always list all fields in the init method to show the class structure
     def __init__(self, parseTree):
         self.parseTree = parseTree
-        self.liType = LiteralNode.toLiType.get(parseTree.children[0].name)  # type of the literal
+        self.name = LiteralNode.toLiType.get(parseTree.children[0].name)  # type of the literal
         self.value = parseTree.children[0].lex # the value
         self.env = None
         self.children = []
 
-        if self.liType == 'int':
+        if self.name == 'int':
             self.value = int(self.value)
-        if self.liType == 'LITERALBOOL':
+        if self.name == 'LITERALBOOL':
             if self.value == 'false':
                 self.value = False
             else: