对网页中各种不同格式的发布时间进行抽取,将发布时间以规整的“yyyy-MM-dd HH:mm:ss”格式表示出来,只能尽量追求精确,但是因为网络发布时间的格式十分灵活,所以做不到百分百地正确抽取
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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 获取网页的发布时间 */ public class FetchPubTime { /** 表示url中连续的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/隔开的日期,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/隔开的日期,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(); /** 格式正确的时间正则表达式*/ 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); //链接里面没有,匹配文本中的 if (pubTime == null ) { if (urlContent!= null &&!urlContent.trim().equals( "" )) return extractPageDate(urlContent); } return pubTime; } /**从url里面抽取出发布时间,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()); //每一步都不能够超出当前时间 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 ; } /** 从网页源码中取出发布时间 * java中正则表达式提取字符串中日期实现代码 * 2013年12月19日15:58:42 * 读取出2013-12-19 15:48:33或者2013-12-19或者2012/3/05形式的时间 * @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); //如果是仅仅抽取年月日,则按照上面的,如果是抽取年月日-时分秒,则按照下面的 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(); //取出第一个值 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 ; } } |
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