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Java > Open Source Codes > org > apache > cayenne > dba > PkRange


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19
20
21 package org.apache.cayenne.dba;
22
23 /**
24  * Represents data structure to maintain a range of cached
25  * primary keys.
26  *
27  * @author Andrus Adamchik
28  */
29 public final class PkRange {
30     private int curValue;
31     private int maxValue;
32
33     public PkRange(int curValue, int maxValue) {
34         reset(curValue, maxValue);
35     }
36
37     public void reset(int curValue, int maxValue) {
38         this.curValue = curValue;
39         this.maxValue = maxValue;
40     }
41
42     public boolean isExhausted() {
43         return curValue > maxValue;
44     }
45
46     public Integer JavaDoc getNextPrimaryKey() {
47         // do bound checking
48 if (isExhausted()) {
49             throw new RuntimeException JavaDoc("PkRange is exhausted and can not be used anymore.");
50         }
51
52         return new Integer JavaDoc(curValue++);
53     }
54 }
55
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