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


1 /* ====================================================================
2  *
3  * The ObjectStyle Group Software License, version 1.1
4  * ObjectStyle Group - http://objectstyle.org/
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6  * Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
7  * of the software. All rights reserved.
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10  * modification, are permitted provided that the following conditions
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24  * and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
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52  * individuals and hosted on ObjectStyle Group web site. For more
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56
57 package org.objectstyle.cayenne.dba;
58
59 /**
60  * Represents data structure to maintain a range of cached
61  * primary keys.
62  *
63  * @author Andrei Adamchik
64  */
65 public final class PkRange {
66     private int curValue;
67     private int maxValue;
68
69     public PkRange(int curValue, int maxValue) {
70         reset(curValue, maxValue);
71     }
72
73     public void reset(int curValue, int maxValue) {
74         this.curValue = curValue;
75         this.maxValue = maxValue;
76     }
77
78     public boolean isExhausted() {
79         return curValue > maxValue;
80     }
81
82     public Integer JavaDoc getNextPrimaryKey() {
83         // do bound checking
84 if (isExhausted()) {
85             throw new RuntimeException JavaDoc("PkRange is exhausted and can not be used anymore.");
86         }
87
88         return new Integer JavaDoc(curValue++);
89     }
90 }
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