1 /*******************************************************************************
2 * Copyright (c) 2007, 2014 Massimiliano Ziccardi
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *******************************************************************************/
16 package it.jnrpe.utils.thresholds;
17
18 import it.jnrpe.Status;
19
20 import java.math.BigDecimal;
21 import java.util.HashMap;
22 import java.util.Map;
23
24 /**
25 * This object take responsability of checking a pair value-metric agains all
26 * the ranges defined for such metric and returns the right {@link Status}
27 * object.
28 *
29 * @author Massimiliano Ziccardi
30 */
31 public class ThresholdsEvaluator {
32
33 /**
34 * Default constructor.
35 */
36 ThresholdsEvaluator() {
37
38 }
39
40 /**
41 * This map contains all the pair METRIC-THRESHOLD.
42 */
43 private Map<String, IThreshold> thresholdsMap =
44 new HashMap<String, IThreshold>();
45
46 /**
47 * Adds a threshold to the list of handled thresholds.
48 *
49 * @param thr
50 * The threshold to add
51 */
52 final void addThreshold(final IThreshold thr) {
53 thresholdsMap.put(thr.getMetric(), thr);
54 }
55
56 /**
57 * Returns <code>true</code> if the requested metric is required.
58 *
59 * @param metricName
60 * The name of the metric
61 * @return <code>true</code> if the metric is required.
62 */
63 final boolean isMetricRequired(final String metricName) {
64 return thresholdsMap.containsKey(metricName);
65 }
66
67 /**
68 * Returns the requested threshold.
69 *
70 * @param metric
71 * The metric name attached to the threshold.
72 * @return The threshold
73 */
74 final IThreshold getThreshold(final String metric) {
75 return thresholdsMap.get(metric);
76 }
77
78 /**
79 * Evaluates the passed in value against the threshold configured
80 * inside this evaluator.
81 * If the threshold do not refer the passed in metric, than it is
82 * ignored and the next threshold is checked.
83 *
84 * @param metric The metric name
85 * @param value The value to be checked
86 * @return The status computed accordin to the rules specified for
87 * {@link IThreshold#evaluate(BigDecimal)}
88 */
89 final Status evaluate(final String metric, final int value) {
90 return evaluate(metric, new BigDecimal(value));
91 }
92
93 /**
94 * Evaluates the passed in value against the threshold configured
95 * inside this evaluator.
96 * If the threshold do not refer the passed in metric, than it is
97 * ignored and the next threshold is checked.
98 *
99 * @param metric The metric name
100 * @param value The value to be checked
101 * @return The status computed accordin to the rules specified for
102 * {@link IThreshold#evaluate(BigDecimal)}
103 */
104 final Status evaluate(final String metric, final BigDecimal value) {
105
106 if (value == null) {
107 throw new NullPointerException(
108 "Value to evaluate can't be null");
109 }
110
111 if (metric == null) {
112 throw new NullPointerException(
113 "Metric name can't be null");
114 }
115
116 IThreshold thr = thresholdsMap.get(metric);
117 if (thr == null) {
118 return Status.OK;
119 }
120
121 return thr.evaluate(value);
122 }
123 }