Coverage Report

Coverage Report - org.kuali.student.core.statement.ui.client.widgets.rules.RuleExpressionParser

Classes in this File

Line Coverage

Branch Coverage

Complexity

RuleExpressionParser

0/285

0/304

8.381

 /**
  * Copyright 2010 The Kuali Foundation Licensed under the
  * Educational Community License, Version 2.0 (the "License"); you may
  * not use this file except in compliance with the License. You may
  * obtain a copy of the License at
  *
  * http://www.osedu.org/licenses/ECL-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an "AS IS"
  * BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
  * or implied. See the License for the specific language governing
  * permissions and limitations under the License.
  */
 
 package org.kuali.student.core.statement.ui.client.widgets.rules;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Stack;
 
 import org.kuali.student.core.statement.dto.StatementInfo;
 import org.kuali.student.core.statement.dto.StatementOperatorTypeKey;
 import org.kuali.student.core.statement.ui.client.widgets.table.Node;
 
 import com.google.gwt.core.client.GWT;
 
 public class RuleExpressionParser {
     
     private String expression;
     private List<Token> tokenList;
        
     private void checkExpressionSet() {
         if (tokenList == null || expression == null) {
             throw new java.lang.IllegalStateException("setExpression must be called first");
         }
     }
 
     public void checkMissingRCs(List<ReqComponentVO> missingRCs, List<ReqComponentVO> rcs) {
         checkExpressionSet();
 
         List<String> conditionValues = new ArrayList<String>();        
         for (Token token : tokenList) {
             if (token.type == Token.Condition) {
                 conditionValues.add(token.value);
             }
         }
 
         if (rcs != null && !rcs.isEmpty()) {
             for (ReqComponentVO rc : rcs) {
                 boolean foundId = false;
                 if (!conditionValues.isEmpty()) {
                     for (String conditionValue : conditionValues) {
                         if (conditionValue != null && conditionValue.equalsIgnoreCase(rc.getGuiReferenceLabelId())) {
                             foundId = true;
                             break;
                         }
                     }
                 }
                 if (!foundId) {
                     missingRCs.add(rc);
                 }
             }
         }
     }
 
     public boolean validateExpression(List<String> errorMessages, List<ReqComponentVO> validRCs) {
         checkExpressionSet();
         return doValidateExpression(errorMessages, tokenList, validRCs);
     }    
     
     private boolean doValidateExpression(List<String> errorMessages, final List<Token> tokens, List<ReqComponentVO> validRCs) {
         boolean valid = true;
         List<String> seenConditonValues = new ArrayList<String>();
         // allow empty expression. ie. user wants the entire rule deleted.
         if (tokens.size() == 0) {
             return true;
         }
 
         if ((tokens.get(0).type == Token.StartParenthesis 
                 || tokens.get(0).type == Token.Condition) == false) {
             errorMessages.add("must start with ( or condition");
             return false;
         }
         int lastIndex = tokens.size() - 1;
         if ((tokens.get(lastIndex).type == Token.EndParenthesis || tokens.get(lastIndex).type == Token.Condition) == false) {
             errorMessages.add("must end with ) or condition");
             return false;
         }
         if (countToken(tokens, Token.StartParenthesis) != countToken(tokens, Token.EndParenthesis)) {
             errorMessages.add("() not in pair");
             return false;
         }
         // condition cannot duplicate
         for (int i = 0; i < tokens.size(); i++) {
             Token token = tokens.get(i);
             if (token.type == Token.And) {
                 if (!checkAnd(errorMessages, tokens, i)) {
                     return false;
                 }
             } else if (token.type == Token.Or) {
                 if (!checkOr(errorMessages, tokens, i)) {
                     return false;
                 }
             } else if (token.type == Token.StartParenthesis) {
                 if (!checkStartParenthesis(errorMessages, tokens, i)) {
                     return false;
                 }
             } else if (token.type == Token.EndParenthesis) {
                 if (!checkEndParenthesis(errorMessages, tokens, i)) {
                     return false;
                 }
             } else if (token.type == Token.Condition) {
                 if (seenConditonValues.contains(token.value)) {
                     errorMessages.add("Condition " + token.value + " is duplicated.");
                     return false;
                 } else {
                     seenConditonValues.add(token.value);
                 }
                 if (!checkCondition(errorMessages, tokens, i, validRCs)) {
                     return false;
                 }
             }
         }
         return valid;
     }
     
     private int countToken(List<Token> tokenList, int type) {
         int count = 0;
         for (Token t : tokenList) {
             if (t.type == type) {
                 count++;
             }
         }
         return count;
     }
 
     private boolean checkAnd(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
         Token prevToken = (tokenList == null || currentIndex - 1 < 0)? null :
             tokenList.get(currentIndex - 1);
         Token nextToken = (tokenList == null || currentIndex + 1 >= tokenList.size())? null :
             tokenList.get(currentIndex + 1);
         boolean validToken = true;
         if (prevToken != null && (prevToken.type == Token.Condition || prevToken.type == Token.EndParenthesis) == false) {
             errorMessages.add("only ) and condition could sit before and");
             validToken = false;
         }
         if (nextToken != null && (nextToken.type == Token.Condition || nextToken.type == Token.StartParenthesis) == false) {
             errorMessages.add("only ( and condition could sit after and");
             validToken = false;
         }
         return validToken;
     }
 
     private boolean checkOr(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
         Token prevToken = (tokenList == null || currentIndex - 1 < 0)? null :
             tokenList.get(currentIndex - 1);
         Token nextToken = (tokenList == null || currentIndex + 1 >= tokenList.size())? null :
             tokenList.get(currentIndex + 1);
         boolean validToken = true;
         if (prevToken != null && (prevToken.type == Token.Condition || prevToken.type == Token.EndParenthesis) == false) {
             errorMessages.add("only ) and condition could sit before or");
             validToken = false;
         }
         if (nextToken != null && (nextToken.type == Token.Condition || nextToken.type == Token.StartParenthesis) == false) {
             errorMessages.add("only ( and condition could sit after or");
             validToken = false;
         }
         return validToken;
     }
 
     private boolean checkStartParenthesis(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
         Token prevToken = (tokenList == null || currentIndex - 1 < 0)? null :
             tokenList.get(currentIndex - 1);
         Token nextToken = (tokenList == null || currentIndex + 1 >= tokenList.size())? null :
             tokenList.get(currentIndex + 1);
         boolean validToken = true;
         if (prevToken != null && (prevToken.type == Token.And || prevToken.type == Token.Or || prevToken.type == Token.StartParenthesis) == false) {
             errorMessages.add("only and, or, ( could sit before (");
             validToken = false;
         }
         if (nextToken != null && (nextToken.type == Token.Condition || nextToken.type == Token.StartParenthesis) == false) {
             errorMessages.add("only ( and condition could sit after (");
             validToken = false;
         }
         return validToken;
     }
 
     private boolean checkEndParenthesis(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
         Token prevToken = (tokenList == null || currentIndex - 1 < 0)? null :
             tokenList.get(currentIndex - 1);
         Token nextToken = (tokenList == null || currentIndex + 1 >= tokenList.size())? null :
             tokenList.get(currentIndex + 1);
         boolean validToken = true;
         if (prevToken != null && (prevToken.type == Token.Condition || prevToken.type == Token.EndParenthesis) == false) {
             errorMessages.add("only condition and ) could sit before )");
             validToken = false;
         }
         if (nextToken != null && (nextToken.type == Token.Or || nextToken.type == Token.And || nextToken.type == Token.EndParenthesis) == false) {
             errorMessages.add("only ), and, or could sit after )");
             validToken = false;
         }
         return validToken;
     }
 
     private boolean checkCondition(List<String> errorMessages, List<Token> tokenList, int currentIndex,
             List<ReqComponentVO> validRCs) {
         Token prevToken = (tokenList == null || currentIndex - 1 < 0)? null :
             tokenList.get(currentIndex - 1);
         Token nextToken = (tokenList == null || currentIndex + 1 >= tokenList.size())? null :
             tokenList.get(currentIndex + 1);
         boolean validToken = true;
         if (prevToken != null && (prevToken.type == Token.And || prevToken.type == Token.Or || prevToken.type == Token.StartParenthesis) == false) {
             errorMessages.add("only and, or could sit before condition");
             validToken = false;
         }
         if (nextToken != null && (nextToken.type == Token.Or || nextToken.type == Token.And || nextToken.type == Token.EndParenthesis) == false) {
             errorMessages.add("only ), and, or could sit after condition");
             validToken = false;
         }
         Token conditionToken = tokenList.get(currentIndex);
         String conditionLetter = conditionToken.value;
         boolean validConditonLetter = false;
         if (validRCs != null) {
             for (ReqComponentVO rc : validRCs) {
                 if (rc.getGuiReferenceLabelId() != null &&
                         rc.getGuiReferenceLabelId().equalsIgnoreCase(conditionLetter)) {
                     validConditonLetter = true;
                 }
             }
         }
         if (!validConditonLetter) {
             errorMessages.add(conditionLetter + " is not a valid conditon");
             validToken = false;
         }
         return validToken;
     }
     
     public Node parseExpressionIntoTree(String expression, StatementVO statementVO, String statementType) {
         Node tree = null;
         if (expression != null && expression.trim().length() > 0) {
             StatementVO parsedS = parseExpressionIntoStatementVO(expression, statementVO, statementType);
             if (parsedS != null) {
                 tree = parsedS.getTree();
             }
         }
         return tree;
     }
     
     public StatementVO parseExpressionIntoStatementVO(String expression, StatementVO statementVO, String statementType) {
         StatementVO parsedS = null;
 
         if (expression.trim().isEmpty()) {
             statementVO.clearStatementAndReqComponents();
             return statementVO;
         }
 
         List<ReqComponentVO> rcs = statementVO.getAllReqComponentVOs();
         try {
             List<String> tokenValueList = getTokenValue(expression);
             List<Token> tokenList = getTokenList(tokenValueList);
             if (!doValidateExpression(new ArrayList<String>(), tokenList, rcs)) return null;
             List<Node<Token>> nodeList = toNodeList(tokenList);
             List<Node<Token>> rpnList = getRPN(nodeList);
             parsedS = statementVOFromRPN(rpnList, rcs, statementType);
 
             if (parsedS != null) {
                 parsedS.simplify();
             }
         } catch (Exception error) {
             GWT.log("Exception parsing",error);
         }
         return parsedS;
     }
     
     private ReqComponentVO lookupReqComponent(List<ReqComponentVO> rcs, String guiKey) {
         ReqComponentVO result = null;
         if (rcs != null) {
             for (ReqComponentVO rc : rcs) {
                 if (rc.getGuiReferenceLabelId() != null && rc.getGuiReferenceLabelId().equalsIgnoreCase(guiKey)) {
                     result = rc;
                     break;
                 }
             }
         }
         return result;
     }
     
     /** Build the binary tree from list of tokens*/
     private StatementVO statementVOFromRPN(List<Node<Token>> rpnList, List<ReqComponentVO> rcs, String statementType) {
         StatementVO statementVO;        
 
         //if rule is empty
         if (rpnList.size() == 0) {
             return new StatementVO();
         }
 
         Stack<Node<? extends Token>> conditionStack = new Stack<Node<? extends Token>>();
         for (Node<Token> node : rpnList) {
             if (node.getUserObject().type == Token.Condition) {
                 ReqComponentVO rc = null;
                 Node<ReqComponentVO> rcNode = null;
                 rc = lookupReqComponent(rcs, node.getUserObject().value);
                 if (rc != null) {
                     rcNode = new Node<ReqComponentVO>();
                     rcNode.setUserObject(rc);
                 }
                 conditionStack.push(rcNode);
             } else if (node.getUserObject().type == Token.And || node.getUserObject().type == Token.Or) {
                 StatementVO subS = new StatementVO();
                 subS.setTokenOperator(true);
                 StatementOperatorTypeKey op = null;
                 if (node.getUserObject().type == Token.And) {
                     op = StatementOperatorTypeKey.AND;
                 } else if (node.getUserObject().type == Token.Or) {
                     op = StatementOperatorTypeKey.OR;
                 }
                 StatementInfo statementInfo = new StatementInfo();
                 statementInfo.setOperator(op);
                 statementInfo.setType(statementType);
                 subS.setStatementInfo(statementInfo);
                 Token right = conditionStack.pop().getUserObject();
                 Token left = conditionStack.pop().getUserObject();
                 List<ReqComponentVO> nodeRcs = new ArrayList<ReqComponentVO>();
                 if (left instanceof ReqComponentVO) {
                     nodeRcs.add((ReqComponentVO) left);
                 }
                 if (right instanceof ReqComponentVO) {
                     nodeRcs.add((ReqComponentVO) right);
                 }
                 // if both left and right nodes are rcs add them into the list of rcs in subS
                 // otherwise wrap the one that is a RC and add the left and right tokens as statementVO into subS
                 if (nodeRcs != null && nodeRcs.size() == 2) {
                     subS.addReqComponentVOs(nodeRcs);
                 } else {
                     if (left instanceof ReqComponentVO) {
                         subS.addStatementVO(wrapReqComponent(op, (ReqComponentVO)left, statementType));
                     } else {
                         subS.addStatementVO((StatementVO)left);
                     }
                     if (right instanceof ReqComponentVO) {
                         subS.addStatementVO(wrapReqComponent(op, (ReqComponentVO)right, statementType));
                     } else {
                         subS.addStatementVO((StatementVO)right);
                     }
                 }
                 
                 Node<StatementVO> nodeS = new Node<StatementVO>();
                 nodeS.setUserObject(subS);
                 conditionStack.push(nodeS);
             }
         }
         
         if (conditionStack.peek().getUserObject() instanceof ReqComponentVO) {
             statementVO = wrapReqComponent(StatementOperatorTypeKey.AND,
                     (ReqComponentVO)conditionStack.pop().getUserObject(), statementType);
         } else {
             statementVO = (StatementVO)conditionStack.pop().getUserObject();
         }
         statementVO.getStatementInfo().setType(statementType);
 
         return statementVO;
     }
     
     private StatementVO wrapReqComponent(StatementOperatorTypeKey op, ReqComponentVO rc, String statementType) {
         StatementVO wrapS = new StatementVO();
         StatementInfo wrapStatementInfo = new StatementInfo();
         wrapStatementInfo.setOperator(op);
         wrapStatementInfo.setType(statementType);
         wrapS.setStatementInfo(wrapStatementInfo);
         wrapS.addReqComponentVO(rc);
         return wrapS;
     }
     
     /**
      * If higher push to stack, else pop till less than or equal, add to list push to stack if ( push to stack if ) pop to
      * list till (.
      * 
      * http://en.wikipedia.org/wiki/Reverse_Polish_notation
      * 
      */
     private List<Node<Token>> getRPN(List<Node<Token>> nodeList) {
         List<Node<Token>> rpnList = new ArrayList<Node<Token>>();
         Stack<Node<Token>> operatorStack = new Stack<Node<Token>>();
 
         for (Node<Token> node : nodeList) {
             if (node.getUserObject().type == Token.Condition) {
                 rpnList.add(node);
 
             } else if (node.getUserObject().type == Token.And) {
                 operatorStack.push(node);
             } else if (node.getUserObject().type == Token.StartParenthesis) {
                 operatorStack.push(node);
             } else if (node.getUserObject().type == Token.Or) {
 
                 if (operatorStack.isEmpty() == false && operatorStack.peek().getUserObject().type == Token.And) {
                     do {
                         rpnList.add(operatorStack.pop());
                     } while (operatorStack.isEmpty() == false && operatorStack.peek().getUserObject().type == Token.And);
                 }
 
                 operatorStack.push(node);
             } else if (node.getUserObject().type == Token.EndParenthesis) {
                 while (operatorStack.peek().getUserObject().type != Token.StartParenthesis) {
                     rpnList.add(operatorStack.pop());
                 }
                 operatorStack.pop();// pop the (
             }
         }
         if (operatorStack.isEmpty() == false) {
             do {
                 rpnList.add(operatorStack.pop());
             } while (operatorStack.isEmpty() == false);
         }
         return rpnList;
     }
     
     private List<Node<Token>> toNodeList(List<Token> tokenList) {
         List<Node<Token>> nodeList = new ArrayList<Node<Token>>();
         for (Token token : tokenList) {
             Node<Token> node = new Node<Token>();
             node.setUserObject(token);
             nodeList.add(node);
         }
         return nodeList;
     }
     
     private List<Token> getTokenList(List<String> tokenValueList) {
         List<Token> tokenList = new ArrayList<Token>();
         for (String value : tokenValueList) {
             if (value.isEmpty()) {
                 continue;
             }
             if ("(".equals(value)) {
                 Token t = new Token();
                 t.type = Token.StartParenthesis;
                 tokenList.add(t);
             } else if (")".equals(value)) {
                 Token t = new Token();
                 t.type = Token.EndParenthesis;
                 tokenList.add(t);
 
             } else if ("and".equals(value)) {
                 Token t = new Token();
                 t.type = Token.And;
                 tokenList.add(t);
 
             } else if ("or".equals(value)) {
                 Token t = new Token();
                 t.type = Token.Or;
                 tokenList.add(t);
 
             } else {
                 Token t = new Token();
                 t.type = Token.Condition;
                 t.value = value;
                 tokenList.add(t);
 
             }
         }
         return tokenList;
     }
     
     private List<String> getTokenValue(String expression) {
         expression = expression.toLowerCase();
         List<String> tokenValueList = new ArrayList<String>();
         StringBuffer tokenValue = new StringBuffer();
         for (int i = 0; i < expression.length(); i++) {
 
             char ch = expression.charAt(i);
             if (ch == ' ') {
                 tokenValueList.add(tokenValue.toString());
                 tokenValue = new StringBuffer();
             } else if (ch == '(' || ch == ')') {
                 tokenValueList.add(tokenValue.toString());
                 tokenValue = new StringBuffer();
                 tokenValueList.add(String.valueOf(ch));
             } else {
                 tokenValue.append(ch);
             }
         }
         tokenValueList.add(tokenValue.toString());
         return tokenValueList;
     }
 
     public void setExpression(String expression) {
         this.expression = expression;
         List<String> tokenValueList = getTokenValue(expression);
         this.tokenList = getTokenList(tokenValueList);
     }
 
     public String getExpression() {
         return expression;
     }    
         
 }

1		/**
2		* Copyright 2010 The Kuali Foundation Licensed under the
3		* Educational Community License, Version 2.0 (the "License"); you may
4		* not use this file except in compliance with the License. You may
5		* obtain a copy of the License at
6		*
7		* http://www.osedu.org/licenses/ECL-2.0
8		*
9		* Unless required by applicable law or agreed to in writing,
10		* software distributed under the License is distributed on an "AS IS"
11		* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
12		* or implied. See the License for the specific language governing
13		* permissions and limitations under the License.
14		*/
15
16		package org.kuali.student.core.statement.ui.client.widgets.rules;
17
18		import java.util.ArrayList;
19		import java.util.List;
20		import java.util.Stack;
21
22		import org.kuali.student.core.statement.dto.StatementInfo;
23		import org.kuali.student.core.statement.dto.StatementOperatorTypeKey;
24		import org.kuali.student.core.statement.ui.client.widgets.table.Node;
25
26		import com.google.gwt.core.client.GWT;
27
28	0	public class RuleExpressionParser {
29
30		private String expression;
31		private List<Token> tokenList;
32
33		private void checkExpressionSet() {
34	0	if (tokenList == null \|\| expression == null) {
35	0	throw new java.lang.IllegalStateException("setExpression must be called first");
36		}
37	0	}
38
39		public void checkMissingRCs(List<ReqComponentVO> missingRCs, List<ReqComponentVO> rcs) {
40	0	checkExpressionSet();
41
42	0	List<String> conditionValues = new ArrayList<String>();
43	0	for (Token token : tokenList) {
44	0	if (token.type == Token.Condition) {
45	0	conditionValues.add(token.value);
46		}
47		}
48
49	0	if (rcs != null && !rcs.isEmpty()) {
50	0	for (ReqComponentVO rc : rcs) {
51	0	boolean foundId = false;
52	0	if (!conditionValues.isEmpty()) {
53	0	for (String conditionValue : conditionValues) {
54	0	if (conditionValue != null && conditionValue.equalsIgnoreCase(rc.getGuiReferenceLabelId())) {
55	0	foundId = true;
56	0	break;
57		}
58		}
59		}
60	0	if (!foundId) {
61	0	missingRCs.add(rc);
62		}
63	0	}
64		}
65	0	}
66
67		public boolean validateExpression(List<String> errorMessages, List<ReqComponentVO> validRCs) {
68	0	checkExpressionSet();
69	0	return doValidateExpression(errorMessages, tokenList, validRCs);
70		}
71
72		private boolean doValidateExpression(List<String> errorMessages, final List<Token> tokens, List<ReqComponentVO> validRCs) {
73	0	boolean valid = true;
74	0	List<String> seenConditonValues = new ArrayList<String>();
75		// allow empty expression. ie. user wants the entire rule deleted.
76	0	if (tokens.size() == 0) {
77	0	return true;
78		}
79
80	0	if ((tokens.get(0).type == Token.StartParenthesis
81		\|\| tokens.get(0).type == Token.Condition) == false) {
82	0	errorMessages.add("must start with ( or condition");
83	0	return false;
84		}
85	0	int lastIndex = tokens.size() - 1;
86	0	if ((tokens.get(lastIndex).type == Token.EndParenthesis \|\| tokens.get(lastIndex).type == Token.Condition) == false) {
87	0	errorMessages.add("must end with ) or condition");
88	0	return false;
89		}
90	0	if (countToken(tokens, Token.StartParenthesis) != countToken(tokens, Token.EndParenthesis)) {
91	0	errorMessages.add("() not in pair");
92	0	return false;
93		}
94		// condition cannot duplicate
95	0	for (int i = 0; i < tokens.size(); i++) {
96	0	Token token = tokens.get(i);
97	0	if (token.type == Token.And) {
98	0	if (!checkAnd(errorMessages, tokens, i)) {
99	0	return false;
100		}
101	0	} else if (token.type == Token.Or) {
102	0	if (!checkOr(errorMessages, tokens, i)) {
103	0	return false;
104		}
105	0	} else if (token.type == Token.StartParenthesis) {
106	0	if (!checkStartParenthesis(errorMessages, tokens, i)) {
107	0	return false;
108		}
109	0	} else if (token.type == Token.EndParenthesis) {
110	0	if (!checkEndParenthesis(errorMessages, tokens, i)) {
111	0	return false;
112		}
113	0	} else if (token.type == Token.Condition) {
114	0	if (seenConditonValues.contains(token.value)) {
115	0	errorMessages.add("Condition " + token.value + " is duplicated.");
116	0	return false;
117		} else {
118	0	seenConditonValues.add(token.value);
119		}
120	0	if (!checkCondition(errorMessages, tokens, i, validRCs)) {
121	0	return false;
122		}
123		}
124		}
125	0	return valid;
126		}
127
128		private int countToken(List<Token> tokenList, int type) {
129	0	int count = 0;
130	0	for (Token t : tokenList) {
131	0	if (t.type == type) {
132	0	count++;
133		}
134		}
135	0	return count;
136		}
137
138		private boolean checkAnd(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
139	0	Token prevToken = (tokenList == null \|\| currentIndex - 1 < 0)? null :
140		tokenList.get(currentIndex - 1);
141	0	Token nextToken = (tokenList == null \|\| currentIndex + 1 >= tokenList.size())? null :
142		tokenList.get(currentIndex + 1);
143	0	boolean validToken = true;
144	0	if (prevToken != null && (prevToken.type == Token.Condition \|\| prevToken.type == Token.EndParenthesis) == false) {
145	0	errorMessages.add("only ) and condition could sit before and");
146	0	validToken = false;
147		}
148	0	if (nextToken != null && (nextToken.type == Token.Condition \|\| nextToken.type == Token.StartParenthesis) == false) {
149	0	errorMessages.add("only ( and condition could sit after and");
150	0	validToken = false;
151		}
152	0	return validToken;
153		}
154
155		private boolean checkOr(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
156	0	Token prevToken = (tokenList == null \|\| currentIndex - 1 < 0)? null :
157		tokenList.get(currentIndex - 1);
158	0	Token nextToken = (tokenList == null \|\| currentIndex + 1 >= tokenList.size())? null :
159		tokenList.get(currentIndex + 1);
160	0	boolean validToken = true;
161	0	if (prevToken != null && (prevToken.type == Token.Condition \|\| prevToken.type == Token.EndParenthesis) == false) {
162	0	errorMessages.add("only ) and condition could sit before or");
163	0	validToken = false;
164		}
165	0	if (nextToken != null && (nextToken.type == Token.Condition \|\| nextToken.type == Token.StartParenthesis) == false) {
166	0	errorMessages.add("only ( and condition could sit after or");
167	0	validToken = false;
168		}
169	0	return validToken;
170		}
171
172		private boolean checkStartParenthesis(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
173	0	Token prevToken = (tokenList == null \|\| currentIndex - 1 < 0)? null :
174		tokenList.get(currentIndex - 1);
175	0	Token nextToken = (tokenList == null \|\| currentIndex + 1 >= tokenList.size())? null :
176		tokenList.get(currentIndex + 1);
177	0	boolean validToken = true;
178	0	if (prevToken != null && (prevToken.type == Token.And \|\| prevToken.type == Token.Or \|\| prevToken.type == Token.StartParenthesis) == false) {
179	0	errorMessages.add("only and, or, ( could sit before (");
180	0	validToken = false;
181		}
182	0	if (nextToken != null && (nextToken.type == Token.Condition \|\| nextToken.type == Token.StartParenthesis) == false) {
183	0	errorMessages.add("only ( and condition could sit after (");
184	0	validToken = false;
185		}
186	0	return validToken;
187		}
188
189		private boolean checkEndParenthesis(List<String> errorMessages, List<Token> tokenList, int currentIndex) {
190	0	Token prevToken = (tokenList == null \|\| currentIndex - 1 < 0)? null :
191		tokenList.get(currentIndex - 1);
192	0	Token nextToken = (tokenList == null \|\| currentIndex + 1 >= tokenList.size())? null :
193		tokenList.get(currentIndex + 1);
194	0	boolean validToken = true;
195	0	if (prevToken != null && (prevToken.type == Token.Condition \|\| prevToken.type == Token.EndParenthesis) == false) {
196	0	errorMessages.add("only condition and ) could sit before )");
197	0	validToken = false;
198		}
199	0	if (nextToken != null && (nextToken.type == Token.Or \|\| nextToken.type == Token.And \|\| nextToken.type == Token.EndParenthesis) == false) {
200	0	errorMessages.add("only ), and, or could sit after )");
201	0	validToken = false;
202		}
203	0	return validToken;
204		}
205
206		private boolean checkCondition(List<String> errorMessages, List<Token> tokenList, int currentIndex,
207		List<ReqComponentVO> validRCs) {
208	0	Token prevToken = (tokenList == null \|\| currentIndex - 1 < 0)? null :
209		tokenList.get(currentIndex - 1);
210	0	Token nextToken = (tokenList == null \|\| currentIndex + 1 >= tokenList.size())? null :
211		tokenList.get(currentIndex + 1);
212	0	boolean validToken = true;
213	0	if (prevToken != null && (prevToken.type == Token.And \|\| prevToken.type == Token.Or \|\| prevToken.type == Token.StartParenthesis) == false) {
214	0	errorMessages.add("only and, or could sit before condition");
215	0	validToken = false;
216		}
217	0	if (nextToken != null && (nextToken.type == Token.Or \|\| nextToken.type == Token.And \|\| nextToken.type == Token.EndParenthesis) == false) {
218	0	errorMessages.add("only ), and, or could sit after condition");
219	0	validToken = false;
220		}
221	0	Token conditionToken = tokenList.get(currentIndex);
222	0	String conditionLetter = conditionToken.value;
223	0	boolean validConditonLetter = false;
224	0	if (validRCs != null) {
225	0	for (ReqComponentVO rc : validRCs) {
226	0	if (rc.getGuiReferenceLabelId() != null &&
227		rc.getGuiReferenceLabelId().equalsIgnoreCase(conditionLetter)) {
228	0	validConditonLetter = true;
229		}
230		}
231		}
232	0	if (!validConditonLetter) {
233	0	errorMessages.add(conditionLetter + " is not a valid conditon");
234	0	validToken = false;
235		}
236	0	return validToken;
237		}
238
239		public Node parseExpressionIntoTree(String expression, StatementVO statementVO, String statementType) {
240	0	Node tree = null;
241	0	if (expression != null && expression.trim().length() > 0) {
242	0	StatementVO parsedS = parseExpressionIntoStatementVO(expression, statementVO, statementType);
243	0	if (parsedS != null) {
244	0	tree = parsedS.getTree();
245		}
246		}
247	0	return tree;
248		}
249
250		public StatementVO parseExpressionIntoStatementVO(String expression, StatementVO statementVO, String statementType) {
251	0	StatementVO parsedS = null;
252
253	0	if (expression.trim().isEmpty()) {
254	0	statementVO.clearStatementAndReqComponents();
255	0	return statementVO;
256		}
257
258	0	List<ReqComponentVO> rcs = statementVO.getAllReqComponentVOs();
259		try {
260	0	List<String> tokenValueList = getTokenValue(expression);
261	0	List<Token> tokenList = getTokenList(tokenValueList);
262	0	if (!doValidateExpression(new ArrayList<String>(), tokenList, rcs)) return null;
263	0	List<Node<Token>> nodeList = toNodeList(tokenList);
264	0	List<Node<Token>> rpnList = getRPN(nodeList);
265	0	parsedS = statementVOFromRPN(rpnList, rcs, statementType);
266
267	0	if (parsedS != null) {
268	0	parsedS.simplify();
269		}
270	0	} catch (Exception error) {
271	0	GWT.log("Exception parsing",error);
272	0	}
273	0	return parsedS;
274		}
275
276		private ReqComponentVO lookupReqComponent(List<ReqComponentVO> rcs, String guiKey) {
277	0	ReqComponentVO result = null;
278	0	if (rcs != null) {
279	0	for (ReqComponentVO rc : rcs) {
280	0	if (rc.getGuiReferenceLabelId() != null && rc.getGuiReferenceLabelId().equalsIgnoreCase(guiKey)) {
281	0	result = rc;
282	0	break;
283		}
284		}
285		}
286	0	return result;
287		}
288
289		/** Build the binary tree from list of tokens*/
290		private StatementVO statementVOFromRPN(List<Node<Token>> rpnList, List<ReqComponentVO> rcs, String statementType) {
291		StatementVO statementVO;
292
293		//if rule is empty
294	0	if (rpnList.size() == 0) {
295	0	return new StatementVO();
296		}
297
298	0	Stack<Node<? extends Token>> conditionStack = new Stack<Node<? extends Token>>();
299	0	for (Node<Token> node : rpnList) {
300	0	if (node.getUserObject().type == Token.Condition) {
301	0	ReqComponentVO rc = null;
302	0	Node<ReqComponentVO> rcNode = null;
303	0	rc = lookupReqComponent(rcs, node.getUserObject().value);
304	0	if (rc != null) {
305	0	rcNode = new Node<ReqComponentVO>();
306	0	rcNode.setUserObject(rc);
307		}
308	0	conditionStack.push(rcNode);
309	0	} else if (node.getUserObject().type == Token.And \|\| node.getUserObject().type == Token.Or) {
310	0	StatementVO subS = new StatementVO();
311	0	subS.setTokenOperator(true);
312	0	StatementOperatorTypeKey op = null;
313	0	if (node.getUserObject().type == Token.And) {
314	0	op = StatementOperatorTypeKey.AND;
315	0	} else if (node.getUserObject().type == Token.Or) {
316	0	op = StatementOperatorTypeKey.OR;
317		}
318	0	StatementInfo statementInfo = new StatementInfo();
319	0	statementInfo.setOperator(op);
320	0	statementInfo.setType(statementType);
321	0	subS.setStatementInfo(statementInfo);
322	0	Token right = conditionStack.pop().getUserObject();
323	0	Token left = conditionStack.pop().getUserObject();
324	0	List<ReqComponentVO> nodeRcs = new ArrayList<ReqComponentVO>();
325	0	if (left instanceof ReqComponentVO) {
326	0	nodeRcs.add((ReqComponentVO) left);
327		}
328	0	if (right instanceof ReqComponentVO) {
329	0	nodeRcs.add((ReqComponentVO) right);
330		}
331		// if both left and right nodes are rcs add them into the list of rcs in subS
332		// otherwise wrap the one that is a RC and add the left and right tokens as statementVO into subS
333	0	if (nodeRcs != null && nodeRcs.size() == 2) {
334	0	subS.addReqComponentVOs(nodeRcs);
335		} else {
336	0	if (left instanceof ReqComponentVO) {
337	0	subS.addStatementVO(wrapReqComponent(op, (ReqComponentVO)left, statementType));
338		} else {
339	0	subS.addStatementVO((StatementVO)left);
340		}
341	0	if (right instanceof ReqComponentVO) {
342	0	subS.addStatementVO(wrapReqComponent(op, (ReqComponentVO)right, statementType));
343		} else {
344	0	subS.addStatementVO((StatementVO)right);
345		}
346		}
347
348	0	Node<StatementVO> nodeS = new Node<StatementVO>();
349	0	nodeS.setUserObject(subS);
350	0	conditionStack.push(nodeS);
351	0	}
352		}
353
354	0	if (conditionStack.peek().getUserObject() instanceof ReqComponentVO) {
355	0	statementVO = wrapReqComponent(StatementOperatorTypeKey.AND,
356		(ReqComponentVO)conditionStack.pop().getUserObject(), statementType);
357		} else {
358	0	statementVO = (StatementVO)conditionStack.pop().getUserObject();
359		}
360	0	statementVO.getStatementInfo().setType(statementType);
361
362	0	return statementVO;
363		}
364
365		private StatementVO wrapReqComponent(StatementOperatorTypeKey op, ReqComponentVO rc, String statementType) {
366	0	StatementVO wrapS = new StatementVO();
367	0	StatementInfo wrapStatementInfo = new StatementInfo();
368	0	wrapStatementInfo.setOperator(op);
369	0	wrapStatementInfo.setType(statementType);
370	0	wrapS.setStatementInfo(wrapStatementInfo);
371	0	wrapS.addReqComponentVO(rc);
372	0	return wrapS;
373		}
374
375		/**
376		* If higher push to stack, else pop till less than or equal, add to list push to stack if ( push to stack if ) pop to
377		* list till (.
378		*
379		* http://en.wikipedia.org/wiki/Reverse_Polish_notation
380		*
381		*/
382		private List<Node<Token>> getRPN(List<Node<Token>> nodeList) {
383	0	List<Node<Token>> rpnList = new ArrayList<Node<Token>>();
384	0	Stack<Node<Token>> operatorStack = new Stack<Node<Token>>();
385
386	0	for (Node<Token> node : nodeList) {
387	0	if (node.getUserObject().type == Token.Condition) {
388	0	rpnList.add(node);
389
390	0	} else if (node.getUserObject().type == Token.And) {
391	0	operatorStack.push(node);
392	0	} else if (node.getUserObject().type == Token.StartParenthesis) {
393	0	operatorStack.push(node);
394	0	} else if (node.getUserObject().type == Token.Or) {
395
396	0	if (operatorStack.isEmpty() == false && operatorStack.peek().getUserObject().type == Token.And) {
397		do {
398	0	rpnList.add(operatorStack.pop());
399	0	} while (operatorStack.isEmpty() == false && operatorStack.peek().getUserObject().type == Token.And);
400		}
401
402	0	operatorStack.push(node);
403	0	} else if (node.getUserObject().type == Token.EndParenthesis) {
404	0	while (operatorStack.peek().getUserObject().type != Token.StartParenthesis) {
405	0	rpnList.add(operatorStack.pop());
406		}
407	0	operatorStack.pop();// pop the (
408		}
409		}
410	0	if (operatorStack.isEmpty() == false) {
411		do {
412	0	rpnList.add(operatorStack.pop());
413	0	} while (operatorStack.isEmpty() == false);
414		}
415	0	return rpnList;
416		}
417
418		private List<Node<Token>> toNodeList(List<Token> tokenList) {
419	0	List<Node<Token>> nodeList = new ArrayList<Node<Token>>();
420	0	for (Token token : tokenList) {
421	0	Node<Token> node = new Node<Token>();
422	0	node.setUserObject(token);
423	0	nodeList.add(node);
424	0	}
425	0	return nodeList;
426		}
427
428		private List<Token> getTokenList(List<String> tokenValueList) {
429	0	List<Token> tokenList = new ArrayList<Token>();
430	0	for (String value : tokenValueList) {
431	0	if (value.isEmpty()) {
432	0	continue;
433		}
434	0	if ("(".equals(value)) {
435	0	Token t = new Token();
436	0	t.type = Token.StartParenthesis;
437	0	tokenList.add(t);
438	0	} else if (")".equals(value)) {
439	0	Token t = new Token();
440	0	t.type = Token.EndParenthesis;
441	0	tokenList.add(t);
442
443	0	} else if ("and".equals(value)) {
444	0	Token t = new Token();
445	0	t.type = Token.And;
446	0	tokenList.add(t);
447
448	0	} else if ("or".equals(value)) {
449	0	Token t = new Token();
450	0	t.type = Token.Or;
451	0	tokenList.add(t);
452
453	0	} else {
454	0	Token t = new Token();
455	0	t.type = Token.Condition;
456	0	t.value = value;
457	0	tokenList.add(t);
458
459	0	}
460		}
461	0	return tokenList;
462		}
463
464		private List<String> getTokenValue(String expression) {
465	0	expression = expression.toLowerCase();
466	0	List<String> tokenValueList = new ArrayList<String>();
467	0	StringBuffer tokenValue = new StringBuffer();
468	0	for (int i = 0; i < expression.length(); i++) {
469
470	0	char ch = expression.charAt(i);
471	0	if (ch == ' ') {
472	0	tokenValueList.add(tokenValue.toString());
473	0	tokenValue = new StringBuffer();
474	0	} else if (ch == '(' \|\| ch == ')') {
475	0	tokenValueList.add(tokenValue.toString());
476	0	tokenValue = new StringBuffer();
477	0	tokenValueList.add(String.valueOf(ch));
478		} else {
479	0	tokenValue.append(ch);
480		}
481		}
482	0	tokenValueList.add(tokenValue.toString());
483	0	return tokenValueList;
484		}
485
486		public void setExpression(String expression) {
487	0	this.expression = expression;
488	0	List<String> tokenValueList = getTokenValue(expression);
489	0	this.tokenList = getTokenList(tokenValueList);
490	0	}
491
492		public String getExpression() {
493	0	return expression;
494		}
495
496		}