OpenConcerto

Dépôt officiel du code source de l'ERP OpenConcerto
sonarqube

svn://code.openconcerto.org/openconcerto

Rev

Rev 144 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
17 ilm 1 
/*
2 
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 
 *
4 
 * Copyright 2011 OpenConcerto, by ILM Informatique. All rights reserved.
5 
 *
6 
 * The contents of this file are subject to the terms of the GNU General Public License Version 3
7 
 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a
8 
 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific
9 
 * language governing permissions and limitations under the License.
10 
 *
11 
 * When distributing the software, include this License Header Notice in each file.
12 
 */
13 
 
14 
 package org.openconcerto.utils.cc;
15 
 
180 ilm 16 
public abstract class IPredicate<E> {
17 ilm 17 
 
18 
    private static final IPredicate<Object> truePred = new IPredicate<Object>() {
19 
        @Override
20 
        public boolean evaluateChecked(Object input) {
21 
            return true;
22 
        }
23 
    };
21 ilm 24 
    private static final IPredicate<Object> falsePred = new IPredicate<Object>() {
25 
        @Override
26 
        public boolean evaluateChecked(Object input) {
27 
            return false;
28 
        }
29 
    };
19 ilm 30 
    private static final IPredicate<Object> NotNullPred = new IPredicate<Object>() {
31 
        @Override
32 
        public boolean evaluateChecked(Object input) {
33 
            return input != null;
34 
        }
35 
    };
17 ilm 36 
 
37 
    @SuppressWarnings("unchecked")
38 
    public static final <N> IPredicate<N> truePredicate() {
39 
        return (IPredicate<N>) truePred;
40 
    }
41 
 
42 
    @SuppressWarnings("unchecked")
21 ilm 43 
    public static final <N> IPredicate<N> falsePredicate() {
44 
        return (IPredicate<N>) falsePred;
45 
    }
46 
 
47 
    @SuppressWarnings("unchecked")
19 ilm 48 
    public static final <N> IPredicate<N> notNullPredicate() {
49 
        return (IPredicate<N>) NotNullPred;
50 
    }
51 
 
17 ilm 52 
    public abstract boolean evaluateChecked(E input);
53 
 
21 ilm 54 
    public final <F extends E> IPredicate<F> cast() {
55 
        // this class never returns E, only takes it as argument
56 
        // but we cannot return this instance :
57 
        // class Sub<E> extends IPredicate<E> {
58 
        // E someMethod();
59 
        // }
60 
        // Sub<Number> n;
61 
        // IPredicate<Integer> cast = n.<Integer> cast();
62 
        // Sub<Integer> n2 = (Sub<Integer>) cast;
63 
        // the cast in the line above will succeed but n2.someMethod()
64 
        // will fail if n.someMethod() returns a BigDecimal
65 
 
66 
        // since we're returning a new IPredicate instance, the n2 line would correctly fail
67 
        return new IPredicate<F>() {
68 
            @Override
69 
            public boolean evaluateChecked(F input) {
70 
                return IPredicate.this.evaluateChecked(input);
71 
            }
72 
        };
73 
    }
74 
 
75 
    public final IPredicate<E> not() {
76 
        if (this == truePred)
77 
            return falsePredicate();
78 
        else if (this == falsePred)
79 
            return truePredicate();
80 
        else
81 
            return new IPredicate<E>() {
82 
                @Override
83 
                public boolean evaluateChecked(E input) {
84 
                    return !IPredicate.this.evaluateChecked(input);
85 
                }
86 
            };
87 
    }
88 
 
89 
    public final IPredicate<E> and(final IPredicate<? super E> o) {
90 
        if (o == this || o == truePred)
91 
            return this;
92 
        else if (this == truePred)
93 
            return o.cast();
94 
        else if (o == falsePred || this == falsePred)
95 
            return falsePredicate();
96 
        else
97 
            return new IPredicate<E>() {
98 
                @Override
99 
                public boolean evaluateChecked(E input) {
100 
                    return IPredicate.this.evaluateChecked(input) && o.evaluateChecked(input);
101 
                }
102 
            };
103 
    }
104 
 
105 
    public final IPredicate<E> or(final IPredicate<? super E> o) {
106 
        if (o == this || o == falsePred)
107 
            return this;
108 
        else if (this == falsePred)
109 
            return o.cast();
110 
        else if (o == truePred || this == truePred)
111 
            return truePredicate();
112 
        else
113 
            return new IPredicate<E>() {
114 
                @Override
115 
                public boolean evaluateChecked(E input) {
116 
                    return IPredicate.this.evaluateChecked(input) || o.evaluateChecked(input);
117 
                }
118 
            };
119 
    }
17 ilm 120 
}