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1 package org.hibernate.hql.classic;
3
4 import org.hibernate.QueryException;
5
6 import java.util.ArrayList  ;
7 import java.util.Iterator ;
8 import java.util.List ;
9
10
13 public class ClauseParser implements Parser {
14
15 private Parser child;
16 private List selectTokens;
17 private boolean cacheSelectTokens = false;
18 private boolean byExpected = false;
19 private int parenCount = 0;
20
21 public void token(String token, QueryTranslatorImpl q) throws QueryException {
22 String lcToken = token.toLowerCase();
23
24 if ( "(".equals( token ) ) {
25 parenCount++;
26 }
27 else if ( ")".equals( token ) ) {
28 parenCount--;
29 }
30
31 if ( byExpected && !lcToken.equals( "by" ) ) {
32 throw new QueryException( "BY expected after GROUP or ORDER: " + token );
33 }
34
35 boolean isClauseStart = parenCount == 0;
37 if ( isClauseStart ) {
38 if ( lcToken.equals( "select" ) ) {
39 selectTokens = new ArrayList ();
40 cacheSelectTokens = true;
41 }
42 else if ( lcToken.equals( "from" ) ) {
43 child = new FromParser();
44 child.start( q );
45 cacheSelectTokens = false;
46 }
47 else if ( lcToken.equals( "where" ) ) {
48 endChild( q );
49 child = new WhereParser();
50 child.start( q );
51 }
52 else if ( lcToken.equals( "order" ) ) {
53 endChild( q );
54 child = new OrderByParser();
55 byExpected = true;
56 }
57 else if ( lcToken.equals( "having" ) ) {
58 endChild( q );
59 child = new HavingParser();
60 child.start( q );
61 }
62 else if ( lcToken.equals( "group" ) ) {
63 endChild( q );
64 child = new GroupByParser();
65 byExpected = true;
66 }
67 else if ( lcToken.equals( "by" ) ) {
68 if ( !byExpected ) throw new QueryException( "GROUP or ORDER expected before BY" );
69 child.start( q );
70 byExpected = false;
71 }
72 else {
73 isClauseStart = false;
74 }
75 }
76
77 if ( !isClauseStart ) {
78 if ( cacheSelectTokens ) {
79 selectTokens.add( token );
80 }
81 else {
82 if ( child == null ) {
83 throw new QueryException( "query must begin with SELECT or FROM: " + token );
84 }
85 else {
86 child.token( token, q );
87 }
88 }
89 }
90
91 }
92
93 private void endChild(QueryTranslatorImpl q) throws QueryException {
94 if ( child == null ) {
95 cacheSelectTokens = false;
97 }
98 else {
99 child.end( q );
100 }
101 }
102
103 public void start(QueryTranslatorImpl q) {
104 }
105
106 public void end(QueryTranslatorImpl q) throws QueryException {
107 endChild( q );
108 if ( selectTokens != null ) {
109 child = new SelectParser();
110 child.start( q );
111 Iterator iter = selectTokens.iterator();
112 while ( iter.hasNext() ) {
113 token( ( String ) iter.next(), q );
114 }
115 child.end( q );
116 }
117 byExpected = false;
118 parenCount = 0;
119 cacheSelectTokens = false;
120 }
121
122 }
123
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130 |
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