|
1
10
11 package com.triactive.jdo.store;
12
13 import java.util.ArrayList  ;
14 import java.util.Iterator ;
15
16
17 class FetchStatement
18 {
19 protected final ClassBaseTable mainTable;
20 protected final ArrayList selected = new ArrayList ();
21 protected final ArrayList supertables = new ArrayList ();
22
23 protected StringBuffer conditionList = new StringBuffer ();
24
25 public FetchStatement(ClassBaseTable mainTable)
26 {
27 this.mainTable = mainTable;
28 }
29
30 public int select(Column col)
31 {
32 String columnID = referenceColumn(col);
33
34 if (!selected.contains(columnID))
35 selected.add(columnID);
36
37 return selected.indexOf(columnID) + 1;
38 }
39
40 public String referenceColumn(Column col)
41 {
42 ClassBaseTable t = (ClassBaseTable)col.getTable();
43
44 if (!t.equals(mainTable) && !supertables.contains(t))
45 supertables.add(t);
46
47 return t.getName().toString() + '.' + col.getName().toString();
48 }
49
50 public void andCondition(String condition)
51 {
52 if (conditionList.length() > 0)
53 conditionList.append(" AND ");
54
55 conditionList.append('(').append(condition).append(')');
56 }
57
58 public String toString()
59 {
60 StringBuffer stmt = new StringBuffer ("SELECT ");
61
62 Iterator i = selected.iterator();
63
64 while (i.hasNext())
65 {
66 stmt.append(i.next());
67
68 if (i.hasNext())
69 stmt.append(',');
70 }
71
72 SQLIdentifier mainTableName = mainTable.getName();
73 String mainTableColumnID = referenceColumn(mainTable.getIDMapping().getColumn());
74 StringBuffer joinConditions = new StringBuffer ();
75
76 stmt.append(" FROM ").append(mainTableName);
77
78 i = supertables.iterator();
79
80 while (i.hasNext())
81 {
82 ClassBaseTable supertable = (ClassBaseTable)i.next();
83 String supertableColumnID = referenceColumn(supertable.getIDMapping().getColumn());
84
85 stmt.append(',').append(supertable.getName());
86
87 if (joinConditions.length() > 0)
88 joinConditions.append(" AND ");
89
90 joinConditions.append(mainTableColumnID).append(" = ").append(supertableColumnID);
91 }
92
93 if (joinConditions.length() > 0)
94 {
95 if (conditionList.length() > 0)
96 conditionList = joinConditions.append(" AND (").append(conditionList).append(')');
97 else
98 conditionList = joinConditions;
99 }
100
101 if (conditionList.length() > 0)
102 stmt.append(" WHERE ").append(conditionList);
103
104 return stmt.toString();
105 }
106 }
107 |
Popular Tags |
Java API By Example, From Geeks To Geeks.