對網頁中各種不同格式的發布時間進行抽取,將發布時間以規整的“yyyy-MM-dd HH:mm:ss”格式表示出來,只能盡量追求精確,但是因為網絡發布時間的格式十分靈活,所以做不到百分百地正確抽取
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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
package whu.extract.pubtime.core; import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; import whu.utils.TimeUtil; /** * Created On 2014年3月13日 下午2:49:05 * @description 獲取網頁的發布時間 */ public class FetchPubTime { /** 表示url中連續的8位日期,例如http://www.baidu.com/20140311/2356.html */ private static String url_reg_whole= "([-|/|_]{1}20\\d{6})" ; /** 表示 用-或者/隔開的日期,有年月日的,例如 http://www.baidu.com/2014-3-11/2356.html */ private static String url_reg_sep_ymd = "([-|/|_]{1}20\\d{2}[-|/|_]{1}\\d{1,2}[-|/|_]{1}\\d{1,2})" ; /** 表示 用-或者/隔開的日期,只有年和月份的,例如 http://www.baidu.com/2014-3/2356.html */ private static String url_reg_sep_ym = "([-|/|_]{1}20\\d{2}[-|/|_]{1}\\d{1,2})" ; private static Calendar current = Calendar.getInstance(); /** 格式正確的時間正則表達式*/ private static String rightTimeReg = "^((\\d{2}(([02468][048])|([13579][26]))[\\-\\/\\s]?((((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])))))|(\\d{2}(([02468][1235679])|([13579][01345789]))[\\-\\/\\s]?((((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?((0?[1-9])|(1[0-9])|(2[0-8]))))))(\\s(((0?[0-9])|([1-2][0-3]))\\:([0-5]?[0-9])((\\s)|(\\:([0-5]?[0-9])))))?$" ; /** * @param url * @param urlContent * @return */ public static String getPubTimeVarious(String url,String urlContent) { String pubTime = getPubTimeFromUrl(url); //鏈接里面沒有,匹配文本中的 if (pubTime == null ) { if (urlContent!= null &&!urlContent.trim().equals( "" )) return extractPageDate(urlContent); } return pubTime; } /**從url里面抽取出發布時間,返回YYYY-MM-DD HH:mm:ss格式的字符串 * @param url * @return */ public static String getPubTimeFromUrl(String url) { Pattern p_whole = Pattern.compile(url_reg_whole); Matcher m_whole = p_whole.matcher(url); if (m_whole.find( 0 )&&m_whole.groupCount()> 0 ) { String time = m_whole.group( 0 ); time = time.substring( 1 ,time.length()); //每一步都不能夠超出當前時間 if (current.compareTo(TimeUtil.strToCalendar(time, "yyyyMMdd" ))>= 0 ) { return time.substring( 0 , 4 )+ "-" +time.substring( 4 , 6 )+ "-" + time.substring( 6 , 8 )+ " " + "00:00:00" ; } } p_whole = null ; m_whole = null ; Pattern p_sep = Pattern.compile(url_reg_sep_ymd); Matcher m_sep = p_sep.matcher(url); if (m_sep.find( 0 )&&m_sep.groupCount()> 0 ) { String time = m_sep.group( 0 ); time = time.substring( 1 ,time.length()); String[] seg = time.split( "[-|/|_]{1}" ); Calendar theTime = Calendar.getInstance(); theTime.set(Calendar.YEAR,Integer.parseInt(seg[ 0 ])); theTime.set(Calendar.MONTH, Integer.parseInt(seg[ 1 ])); theTime.set(Calendar.DAY_OF_MONTH, Integer.parseInt(seg[ 2 ])); if (current.compareTo(theTime)>= 0 ) { return seg[ 0 ]+ "-" +seg[ 1 ]+ "-" +seg[ 2 ]+ " " + "00:00:00" ; } } p_sep = null ; m_sep = null ; Pattern p_sep_ym = Pattern.compile(url_reg_sep_ym); Matcher m_sep_ym = p_sep_ym.matcher(url); if (m_sep_ym.find( 0 )&&m_sep_ym.groupCount()> 0 ) { String time = m_sep_ym.group( 0 ); time = time.substring( 1 ,time.length()); Calendar theTime = Calendar.getInstance(); String[] seg = time.split( "[-|/|_]{1}" ); theTime.set(Calendar.YEAR,Integer.parseInt(seg[ 0 ])); theTime.set(Calendar.MONTH, Integer.parseInt(seg[ 1 ])); theTime.set(Calendar.DAY_OF_MONTH, 1 ); if (current.compareTo(theTime)>= 0 ) { return seg[ 0 ]+ "-" +seg[ 1 ]+ "-" + "01" + " " + "00:00:00" ; } } return null ; } /** 從網頁源碼中取出發布時間 * java中正則表達式提取字符串中日期實現代碼 * 2013年12月19日15:58:42 * 讀取出2013-12-19 15:48:33或者2013-12-19或者2012/3/05形式的時間 * @param text 待提取的字符串 * @return 返回日期 * @author: oschina * @Createtime: Jan 21, 2013 */ public static String extractPageDate(String text) { boolean containsHMS = false ; String dateStr = text.replaceAll( "r?n" , " " ); try { List matches = null ; Pattern p_detail = Pattern.compile( "(20\\d{2}[-/]\\d{1,2}[-/]\\d{1,2} \\d{1,2}:\\d{1,2}:\\d{1,2})|(20\\d{2}年\\d{1,2}月\\d{1,2}日)" , Pattern.CASE_INSENSITIVE|Pattern.MULTILINE); //如果是僅僅抽取年月日,則按照上面的,如果是抽取年月日-時分秒,則按照下面的 Pattern p = Pattern.compile( "(20\\d{2}[-/]\\d{1,2}[-/]\\d{1,2})|(20\\d{2}年\\d{1,2}月\\d{1,2}日)" , Pattern.CASE_INSENSITIVE|Pattern.MULTILINE); //Matcher matcher = p.matcher(dateStr); Matcher matcher_detail = p_detail.matcher(dateStr); if (!(matcher_detail.find( 0 ) && matcher_detail.groupCount() >= 1 )) { matcher_detail = p.matcher(dateStr); containsHMS = true ; } else matcher_detail = p_detail.matcher(dateStr); if (matcher_detail.find() && matcher_detail.groupCount() >= 1 ) { matches = new ArrayList(); for ( int i = 1 ; i <= matcher_detail.groupCount(); i++) { String temp = matcher_detail.group(i); matches.add(temp); } } else { matches = Collections.EMPTY_LIST; } if (matches.size() > 0 ) { for ( int i= 0 ;i<matches.size();i++) { String pubTime = matches.get(i).toString().trim(); //取出第一個值 pubTime = pubTime.replace( "/" , "-" ).replace( "年" , "-" ).replace( "月" , "-" ).replace( "日" , "-" ); if (current.compareTo(TimeUtil.strToCalendar(pubTime, "yyyy-MM-dd" ))>= 0 ) { if (containsHMS) pubTime+= " " + "00:00:00" ; if (pubTime.matches(rightTimeReg)) { return pubTime; } } } } else { return null ; } } catch (Exception e) { return null ; } return null ; } } |
以上就是本文的全部內容,希望對大家學習java程序設計有所幫助。