1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/*
* Copyright (C) 2009 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License
*/
package com.android.providers.contacts;
import com.android.providers.contacts.util.Hex;
import com.google.common.annotations.VisibleForTesting;
import java.text.CollationKey;
import java.text.Collator;
import java.text.RuleBasedCollator;
import java.util.Locale;
/**
* Converts a name to a normalized form by removing all non-letter characters and normalizing
* UNICODE according to http://unicode.org/unicode/reports/tr15
*/
public class NameNormalizer {
private static final Object sCollatorLock = new Object();
private static Locale sCollatorLocale;
private static RuleBasedCollator sCachedCompressingCollator;
private static RuleBasedCollator sCachedComplexityCollator;
/**
* Ensure that the cached collators are for the current locale.
*/
private static void ensureCollators() {
final Locale locale = Locale.getDefault();
if (locale.equals(sCollatorLocale)) {
return;
}
sCollatorLocale = locale;
sCachedCompressingCollator = (RuleBasedCollator) Collator.getInstance(locale);
sCachedCompressingCollator.setStrength(Collator.PRIMARY);
sCachedCompressingCollator.setDecomposition(Collator.CANONICAL_DECOMPOSITION);
sCachedComplexityCollator = (RuleBasedCollator) Collator.getInstance(locale);
sCachedComplexityCollator.setStrength(Collator.SECONDARY);
}
@VisibleForTesting
static RuleBasedCollator getCompressingCollator() {
synchronized (sCollatorLock) {
ensureCollators();
return sCachedCompressingCollator;
}
}
@VisibleForTesting
static RuleBasedCollator getComplexityCollator() {
synchronized (sCollatorLock) {
ensureCollators();
return sCachedComplexityCollator;
}
}
/**
* Converts the supplied name to a string that can be used to perform approximate matching
* of names. It ignores non-letter, non-digit characters, and removes accents.
*/
public static String normalize(String name) {
CollationKey key = getCompressingCollator().getCollationKey(lettersAndDigitsOnly(name));
return Hex.encodeHex(key.toByteArray(), true);
}
/**
* Compares "complexity" of two names, which is determined by the presence
* of mixed case characters, accents and, if all else is equal, length.
*/
public static int compareComplexity(String name1, String name2) {
String clean1 = lettersAndDigitsOnly(name1);
String clean2 = lettersAndDigitsOnly(name2);
int diff = getComplexityCollator().compare(clean1, clean2);
if (diff != 0) {
return diff;
}
// compareTo sorts uppercase first. We know that there are no non-case
// differences from the above test, so we can negate here to get the
// lowercase-first comparison we really want...
diff = -clean1.compareTo(clean2);
if (diff != 0) {
return diff;
}
return name1.length() - name2.length();
}
/**
* Returns a string containing just the letters and digits from the original string.
* Returns empty string if the original string is null.
*/
private static String lettersAndDigitsOnly(String name) {
if (name == null) {
return "";
}
char[] letters = name.toCharArray();
int length = 0;
for (int i = 0; i < letters.length; i++) {
final char c = letters[i];
if (Character.isLetterOrDigit(c)) {
letters[length++] = c;
}
}
if (length != letters.length) {
return new String(letters, 0, length);
}
return name;
}
}
|
