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1 package org.hibernate.impl;
3
4 import java.sql.PreparedStatement  ;
5 import java.sql.ResultSet ;
6 import java.sql.SQLException ;
7 import java.util.NoSuchElementException ;
8
9 import org.apache.commons.logging.Log;
10 import org.apache.commons.logging.LogFactory;
11 import org.hibernate.HibernateException;
12 import org.hibernate.JDBCException;
13 import org.hibernate.engine.HibernateIterator;
14 import org.hibernate.event.EventSource;
15 import org.hibernate.exception.JDBCExceptionHelper;
16 import org.hibernate.hql.HolderInstantiator;
17 import org.hibernate.type.EntityType;
18 import org.hibernate.type.Type;
19
20
25 public final class IteratorImpl implements HibernateIterator {
26
27 private static final Log log = LogFactory.getLog(IteratorImpl.class);
28
29 private ResultSet rs;
30 private final EventSource session;
31 private final Type[] types;
32 private final boolean single;
33 private Object currentResult;
34 private boolean hasNext;
35 private final String [][] names;
36 private PreparedStatement ps;
37 private Object nextResult;
38 private HolderInstantiator holderInstantiator;
39
40 public IteratorImpl(
41 ResultSet rs,
42 PreparedStatement ps,
43 EventSource sess,
44 Type[] types,
45 String [][] columnNames,
46 HolderInstantiator holderInstantiator)
47 throws HibernateException, SQLException {
48
49 this.rs=rs;
50 this.ps=ps;
51 this.session = sess;
52 this.types = types;
53 this.names = columnNames;
54 this.holderInstantiator = holderInstantiator;
55
56 single = types.length==1;
57
58 postNext();
59 }
60
61 public void close() throws JDBCException {
62 if (ps!=null) {
63 try {
64 log.debug("closing iterator");
65 nextResult = null;
66 session.getBatcher().closeQueryStatement(ps, rs);
67 ps = null;
68 rs = null;
69 hasNext = false;
70 }
71 catch (SQLException e) {
72 log.info( "Unable to close iterator", e );
73 throw JDBCExceptionHelper.convert(
74 session.getFactory().getSQLExceptionConverter(),
75 e,
76 "Unable to close iterator"
77 );
78 }
79 }
80 }
81
82 private void postNext() throws HibernateException, SQLException {
83 this.hasNext = rs.next();
84 if (!hasNext) {
85 log.debug("exhausted results");
86 close();
87 }
88 else {
89 log.debug("retrieving next results");
90 boolean isHolder = holderInstantiator.isRequired();
91
92 if ( single && !isHolder ) {
93 nextResult = types[0].nullSafeGet( rs, names[0], session, null );
94 }
95 else {
96 Object [] nextResults = new Object [types.length];
97 for (int i=0; i<types.length; i++) {
98 nextResults[i] = types[i].nullSafeGet( rs, names[i], session, null );
99 }
100
101 if (isHolder) {
102 nextResult = holderInstantiator.instantiate(nextResults);
103 }
104 else {
105 nextResult = nextResults;
106 }
107 }
108
109 }
110 }
111
112 public boolean hasNext() {
113 return hasNext;
114 }
115
116 public Object next() {
117 if ( !hasNext ) throw new NoSuchElementException ("No more results");
118 try {
119 currentResult = nextResult;
120 postNext();
121 log.debug("returning current results");
122 return currentResult;
123 }
124 catch (SQLException sqle) {
125 throw JDBCExceptionHelper.convert(
126 session.getFactory().getSQLExceptionConverter(),
127 sqle,
128 "could not get next iterator result"
129 );
130 }
131 }
132
133 public void remove() {
134 if (!single) {
135 throw new UnsupportedOperationException ("Not a single column hibernate query result set");
136 }
137 if (currentResult==null) {
138 throw new IllegalStateException ("Called Iterator.remove() before next()");
139 }
140 if ( !( types[0] instanceof EntityType ) ) {
141 throw new UnsupportedOperationException ("Not an entity");
142 }
143
144 session.delete(
145 ( (EntityType) types[0] ).getAssociatedEntityName(),
146 currentResult,
147 false
148 );
149 }
150
151 }
152 |
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