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1 package com.daffodilwoods.daffodildb.utils.parser;
2
3 import com.daffodilwoods.daffodildb.server.sql99.dql.queryexpression.*;
4 import com.daffodilwoods.daffodildb.utils.parser.QueryProperty;
5 import com.daffodilwoods.database.resource.DException;
6
7 public class QueryReWriter implements _QueryReWriter{
8
9 String  columnList;
10 String orderByClause;
11 String filterClause;
12 String query;
13 queryexpression receivedQuery;
14 boolean clearColumn;
15 boolean clearOrder;
16
17
18
19 public QueryReWriter(String query0) {
20 query = query0;
21
22 }
23 public void addColumnList(String parm1) {
24 columnList = parm1;
25 }
26
27 public void addFilter(String parm1) {
28 filterClause = parm1;
29 }
30
31 public void addOrder(String parm1) {
32 orderByClause = parm1;
33 }
34
35 public void clearColumnList() {
36 clearColumn = true;
37 }
38
39 public void clearOrder() {
40 clearOrder = true;
41 }
42
43 public String getQuery() throws DException{
44 receivedQuery = (queryexpression)Parser.parseQuery(query);
45 QueryProperty queryProperty = receivedQuery.getStrings();
46 StringBuffer newQuery = new StringBuffer ();
47 newQuery.append(" Select ");
48
49 if(!clearColumn){
50 newQuery.append(queryProperty.getColumnList());
51 if(columnList != null){
52 newQuery.append(",");
53 newQuery.append(columnList);
54 }
55 }
56 else
57 newQuery.append(columnList);
58
59 newQuery.append(" ");
60 newQuery.append(queryProperty.getFromClause());
61 newQuery.append(" ");
62 String whereClause = queryProperty.getWhereClause();
63
64 if(filterClause == null && whereClause != null )
65 newQuery.append(whereClause);
66
67 if(filterClause!=null )
68 if(whereClause != null){
69 ; String substr = whereClause.substring(6);
71 newQuery.append(" where (");
72 newQuery.append(substr);
73 newQuery.append(" ) AND (");
74 newQuery.append(filterClause);
75 newQuery.append(" )");
76 }
77 else{
78 newQuery.append(" where ");
79 newQuery.append(filterClause);
80 }
81 newQuery.append(" ");
82
83 newQuery.append(queryProperty.getGroupByClause()== null?" ":queryProperty.getGroupByClause());
84 newQuery.append(" ");
85 newQuery.append(queryProperty.getHavingClause() == null ? " " : queryProperty.getHavingClause());
86
87 if(!clearOrder){
88 String queryOrder = queryProperty.getOrderByClause();
89 if(queryOrder == null){
90 if( orderByClause != null ){
91 newQuery.append(" order by ");
92 newQuery.append(orderByClause);
93 }
94 }
95 else{
96 newQuery.append(queryProperty.getOrderByClause());
97 if(orderByClause!=null){
98 newQuery.append(",");
99 newQuery.append(orderByClause);
100 }
101 }
102 }
103 else if(orderByClause != null){
104 newQuery.append(" order by ");
105 newQuery.append(orderByClause);
106 }
107
108 try{
109 Parser.parseQuery(newQuery.toString());
110 }catch(DException e){
111 throw new DException("DSE1270",(Object [])null);
112 }
113 return newQuery.toString();
114 }
115 }
116 |
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