1/*
2 * Copyright (C) 2015 The Android Open Source Project
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 android.databinding.tool.writer;
18
19import java.util.BitSet;
20
21/**
22 * Used for code generation. A BitSet can be converted into a flag set,
23 * which is basically a list of longs that can be divided into pieces.
24 */
25public class FlagSet {
26    public static final int sBucketSize = 64;// long
27    public final String type;
28    public final long[] buckets;
29    private String mLocalName;
30    private boolean mIsDynamic = false;
31
32    public FlagSet(BitSet bitSet, int bucketCount) {
33        buckets = new long[bucketCount];
34        for (int i = bitSet.nextSetBit(0);
35                i != -1; i = bitSet.nextSetBit(i + 1)) {
36            buckets[i / sBucketSize] |= 1L << (i % sBucketSize);
37        }
38        type = "long";
39    }
40
41    public FlagSet(long[] buckets) {
42        this.buckets = new long[buckets.length];
43        System.arraycopy(buckets, 0, this.buckets, 0, buckets.length);
44        type = "long";
45    }
46
47    public FlagSet(long[] buckets, int minBucketCount) {
48        this.buckets = new long[Math.max(buckets.length, minBucketCount)];
49        System.arraycopy(buckets, 0, this.buckets, 0, buckets.length);
50        type = "long";
51    }
52
53    public FlagSet(int... bits) {
54        int max = 0;
55        for (int i = 0 ; i < bits.length; i ++) {
56            max = Math.max(i, bits[i]);
57        }
58        buckets = new long[1 + (max / sBucketSize)];
59        for (int x = 0 ; x < bits.length; x ++) {
60            final int i = bits[x];
61            buckets[i / sBucketSize] |= 1L << (i % sBucketSize);
62        }
63        type = "long";
64    }
65
66    public boolean intersect(FlagSet other, int bucketIndex) {
67        return (buckets[bucketIndex] & other.buckets[bucketIndex]) != 0;
68    }
69
70    public String getLocalName() {
71        return mLocalName;
72    }
73
74    public void setLocalName(String localName) {
75        mLocalName = localName;
76    }
77
78    public boolean hasLocalName() {
79        return mLocalName != null;
80    }
81
82    public boolean isDynamic() {
83        return mIsDynamic;
84    }
85
86    public void setDynamic(boolean isDynamic) {
87        mIsDynamic = isDynamic;
88    }
89
90    public FlagSet andNot(FlagSet other) {
91        FlagSet result = new FlagSet(buckets);
92        final int min = Math.min(buckets.length, other.buckets.length);
93        for (int i = 0; i < min; i ++) {
94            result.buckets[i] &= ~(other.buckets[i]);
95        }
96        return result;
97    }
98
99    public FlagSet or(FlagSet other) {
100        final FlagSet result = new FlagSet(buckets, other.buckets.length);
101        for (int i = 0; i < other.buckets.length; i ++) {
102            result.buckets[i] |= other.buckets[i];
103        }
104        return result;
105    }
106
107    public boolean isEmpty() {
108        for (int i = 0; i < buckets.length; i ++) {
109            if (buckets[i] != 0) {
110                return false;
111            }
112        }
113        return true;
114    }
115
116    @Override
117    public String toString() {
118        StringBuilder sb = new StringBuilder();
119        for (int i = 0; i < buckets.length; i ++) {
120            sb.append(Long.toBinaryString(buckets[i])).append(" ");
121        }
122        return sb.toString();
123    }
124
125    private long getBucket(int bucketIndex) {
126        if (bucketIndex >= buckets.length) {
127            return 0;
128        }
129        return buckets[bucketIndex];
130    }
131
132    public boolean bitsEqual(FlagSet other) {
133        final int max = Math.max(buckets.length, other.buckets.length);
134        for (int i = 0; i < max; i ++) {
135            if (getBucket(i) != other.getBucket(i)) {
136                return false;
137            }
138        }
139        return true;
140    }
141
142    @Override
143    public int hashCode() {
144        int hash = 1;
145        for (long bucket : buckets) {
146            hash = (hash * 7) ^ (int)(bucket >>> 32);
147            hash = (hash * 13) ^ (int)(bucket & 0xFFFF);
148        }
149        return hash;
150    }
151
152    @Override
153    public boolean equals(Object obj) {
154        if (obj instanceof FlagSet) {
155            FlagSet other = (FlagSet) obj;
156            if (other.buckets.length != buckets.length) {
157                return false;
158            }
159            for (int i = 0; i < buckets.length; i++) {
160                if (buckets[i] != other.buckets[i]) {
161                    return false;
162                }
163            }
164            return true;
165        } else {
166            return false;
167        }
168    }
169}
170