01: /*
02:
03: Derby - Class org.apache.derby.iapi.services.locks.ShExQual
04:
05: Licensed to the Apache Software Foundation (ASF) under one or more
06: contributor license agreements. See the NOTICE file distributed with
07: this work for additional information regarding copyright ownership.
08: The ASF licenses this file to you under the Apache License, Version 2.0
09: (the "License"); you may not use this file except in compliance with
10: the License. You may obtain a copy of the License at
11:
12: http://www.apache.org/licenses/LICENSE-2.0
13:
14: Unless required by applicable law or agreed to in writing, software
15: distributed under the License is distributed on an "AS IS" BASIS,
16: WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17: See the License for the specific language governing permissions and
18: limitations under the License.
19:
20: */
21:
22: package org.apache.derby.iapi.services.locks;
23:
24: /**
25: * This class is intended to be used a the qualifier class for ShExLockable.
26: */
27: public class ShExQual {
28: private int lockState;
29:
30: private ShExQual(int lockState) {
31: this .lockState = lockState;
32: }
33:
34: /*
35: ** These are intentionally package protected. They are intended to
36: ** be used in this class and by ShExLockable, and by no one else.
37: */
38: public static final int SHARED = 0;
39: public static final int EXCLUSIVE = 1;
40:
41: /* Shared Lock */
42: public static final ShExQual SH = new ShExQual(SHARED);
43:
44: /* Exclusive Lock */
45: public static final ShExQual EX = new ShExQual(EXCLUSIVE);
46:
47: public int getLockState() {
48: return lockState;
49: }
50:
51: public String toString() {
52: if (lockState == SHARED)
53: return "S";
54: else
55: return "X";
56: }
57: }
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