1/*
2 * Copyright 2009 Mike Cumings
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
17package com.kenai.jbosh;
18
19/**
20 * Abstract base class for attribute implementations based on {@code Integer}
21 * types.  Additional support for parsing of integer values from their
22 * {@code String} representations as well as callback handling of value
23 * validity checks are also provided.
24 */
25abstract class AbstractIntegerAttr extends AbstractAttr<Integer> {
26
27    /**
28     * Creates a new attribute object.
29     *
30     * @param val attribute value
31     * @throws BOSHException on parse or validation failure
32     */
33    protected AbstractIntegerAttr(final int val) throws BOSHException {
34        super(Integer.valueOf(val));
35    }
36
37    /**
38     * Creates a new attribute object.
39     *
40     * @param val attribute value in string form
41     * @throws BOSHException on parse or validation failure
42     */
43    protected AbstractIntegerAttr(final String val) throws BOSHException {
44        super(parseInt(val));
45    }
46
47    /**
48     * Utility method intended to be called by concrete implementation
49     * classes from within the {@code check()} method when the concrete
50     * class needs to ensure that the integer value does not drop below
51     * the specified minimum value.
52     *
53     * @param minVal minimum value to allow
54     * @throws BOSHException if the integer value is below the specific
55     *  minimum
56     */
57    protected final void checkMinValue(int minVal) throws BOSHException {
58        int intVal = getValue();
59        if (intVal < minVal) {
60            throw(new BOSHException(
61                    "Illegal attribute value '" + intVal + "' provided.  "
62                    + "Must be >= " + minVal));
63        }
64    }
65
66    /**
67     * Utility method to parse a {@code String} into an {@code Integer},
68     * converting any possible {@code NumberFormatException} thrown into
69     * a {@code BOSHException}.
70     *
71     * @param str string to parse
72     * @return integer value
73     * @throws BOSHException on {@code NumberFormatException}
74     */
75    private static int parseInt(final String str) throws BOSHException {
76        try {
77            return Integer.parseInt(str);
78        } catch (NumberFormatException nfx) {
79            throw(new BOSHException(
80                    "Could not parse an integer from the value provided: "
81                    + str,
82                    nfx));
83        }
84    }
85
86    /**
87     * Returns the native {@code int} value of the underlying {@code Integer}.
88     * Will throw {@code NullPointerException} if the underlying
89     * integer was {@code null}.
90     *
91     * @return native {@code int} value
92     */
93    public int intValue() {
94        return getValue().intValue();
95    }
96
97}
98