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1 package org.hibernate.sql;
3
4 import java.util.Iterator  ;
5 import java.util.Map ;
6
7 import org.hibernate.LockMode;
8 import org.hibernate.QueryException;
9 import org.hibernate.dialect.Dialect;
10 import org.hibernate.util.StringHelper;
11
12
15 public class ForUpdateFragment {
16 private final StringBuffer aliases = new StringBuffer ();
17 private boolean isNowaitEnabled;
18 private final Dialect dialect;
19
20 public ForUpdateFragment(Dialect dialect) {
21 this.dialect = dialect;
22 }
23
24 public ForUpdateFragment addTableAlias(String alias) {
25 if ( aliases.length()>0 ) aliases.append(", ");
26 aliases.append(alias);
27 return this;
28 }
29
30 public String toFragmentString() {
31 if ( aliases.length()==0 ) return "";
32 return isNowaitEnabled ?
33 dialect.getForUpdateNowaitString( aliases.toString() ) :
34 dialect.getForUpdateString( aliases.toString() );
35 }
36
37 public ForUpdateFragment setNowaitEnabled(boolean nowait) {
38 isNowaitEnabled = nowait;
39 return this;
40 }
41
42 public ForUpdateFragment(Dialect dialect, Map lockModes, Map keyColumnNames)
43 throws QueryException {
44 this(dialect);
45 LockMode upgradeType = null;
46 Iterator iter = lockModes.entrySet().iterator();
47 while ( iter.hasNext() ) {
48 final Map.Entry me = (Map.Entry ) iter.next();
49 final LockMode lockMode = (LockMode) me.getValue();
50 if ( LockMode.READ.lessThan(lockMode) ) {
51 final String tableAlias = (String ) me.getKey();
52 if ( dialect.forUpdateOfColumns() ) {
53 String [] keyColumns = (String []) keyColumnNames.get(tableAlias); if (keyColumns==null) {
55 throw new IllegalArgumentException ("alias not found: " + tableAlias);
56 }
57 keyColumns = StringHelper.qualify(tableAlias, keyColumns);
58 for (int i=0; i<keyColumns.length; i++) addTableAlias( keyColumns[i] );
59 }
60 else {
61 addTableAlias(tableAlias);
62 }
63 if ( upgradeType!=null && lockMode!=upgradeType ) {
64 throw new QueryException("mixed LockModes");
65 }
66 upgradeType = lockMode;
67 }
68 }
69
70 if ( upgradeType==LockMode.UPGRADE_NOWAIT ) setNowaitEnabled(true);
71 }
72 }
73 |
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