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Java > Open Source Codes > org > apache > cayenne > access > trans > BatchQueryBuilder


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19
20 package org.apache.cayenne.access.trans;
21
22 import java.sql.PreparedStatement JavaDoc;
23 import java.sql.SQLException JavaDoc;
24 import java.sql.Types JavaDoc;
25 import java.util.ArrayList JavaDoc;
26 import java.util.List JavaDoc;
27
28 import org.apache.cayenne.dba.DbAdapter;
29 import org.apache.cayenne.map.DbAttribute;
30 import org.apache.cayenne.query.BatchQuery;
31
32 /**
33  * Superclass of batch query translators.
34  *
35  * @author Andriy Shapochka, Andrus Adamchik
36  */
37
38 public abstract class BatchQueryBuilder {
39
40     protected DbAdapter adapter;
41     protected String JavaDoc trimFunction;
42
43     public BatchQueryBuilder() {
44     }
45
46     public BatchQueryBuilder(DbAdapter adapter) {
47         this.adapter = adapter;
48     }
49
50     /**
51      * Translates BatchQuery into an SQL string formatted to use in a PreparedStatement.
52      */
53     public abstract String JavaDoc createSqlString(BatchQuery batch);
54
55     /**
56      * Appends the name of the column to the query buffer. Subclasses use this method to
57      * append column names in the WHERE clause, i.e. for the columns that are not being
58      * updated.
59      */
60     protected void appendDbAttribute(StringBuffer JavaDoc buf, DbAttribute dbAttribute) {
61
62         // TODO: (Andrus) is there a need for trimming binary types?
63 boolean trim = dbAttribute.getType() == Types.CHAR && trimFunction != null;
64         if (trim) {
65             buf.append(trimFunction).append('(');
66         }
67
68         buf.append(dbAttribute.getName());
69
70         if (trim) {
71             buf.append(')');
72         }
73     }
74
75     public void setAdapter(DbAdapter adapter) {
76         this.adapter = adapter;
77     }
78
79     public DbAdapter getAdapter() {
80         return adapter;
81     }
82
83     public String JavaDoc getTrimFunction() {
84         return trimFunction;
85     }
86
87     public void setTrimFunction(String JavaDoc string) {
88         trimFunction = string;
89     }
90
91     /**
92      * Binds parameters for the current batch iteration to the PreparedStatement.
93      *
94      * @since 1.2
95      */
96     public void bindParameters(PreparedStatement JavaDoc statement, BatchQuery query)
97             throws SQLException JavaDoc, Exception JavaDoc {
98
99         List JavaDoc dbAttributes = query.getDbAttributes();
100         int attributeCount = dbAttributes.size();
101
102         for (int i = 0; i < attributeCount; i++) {
103             Object JavaDoc value = query.getValue(i);
104             DbAttribute attribute = (DbAttribute) dbAttributes.get(i);
105             adapter.bindParameter(statement, value, i + 1, attribute.getType(), attribute
106                     .getScale());
107
108         }
109     }
110
111     /**
112      * Returns a list of values for the current batch iteration. Used primarily for
113      * logging.
114      *
115      * @since 1.2
116      */
117     public List JavaDoc getParameterValues(BatchQuery query) {
118         List JavaDoc attributes = query.getDbAttributes();
119         int len = attributes.size();
120         List JavaDoc values = new ArrayList JavaDoc(len);
121         for (int i = 0; i < len; i++) {
122             values.add(query.getValue(i));
123         }
124         return values;
125     }
126 }
127
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