有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: hETTD%
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CountBean.java yW.s?3X
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/* 8M m,a
* CountData.java kd9rvy0oK
* N%{&%C 6{
* Created on 2007年1月1日, 下午4:44 o.DT`L8
* iivuH2/~?[
* To change this template, choose Tools | Options and locate the template under H"W%+{AR
* the Source Creation and Management node. Right-click the template and choose =/MAKi}g
* Open. You can then make changes to the template in the Source Editor. uGl+"/uDu
*/ gio'_X
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package com.tot.count; kK nz
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/** 1,fjdd8OM;
* q:.URl
* @author \k;)m-0bj{
*/ 9 aT#7B
public class CountBean { #imMkvx?
private String countType; Hs<vCL \
int countId; 'M2Jw8i
/** Creates a new instance of CountData */ "YD<pRVB
public CountBean() {} &G?b|Tb2
public void setCountType(String countTypes){ -?n|kSHX
this.countType=countTypes; H"f%\'
} O`-JKZc
public void setCountId(int countIds){ aloP@U/\Sn
this.countId=countIds; {zhN>n_
} 'bj$Z M9
public String getCountType(){ y8jk9Tv
return countType; @%@uZqQ4
} ,6?L.L
public int getCountId(){ p%5RE%u
return countId; _O~DJ"
} _
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} 8E1swH5z
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CountCache.java lCg'K(|"
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/* RVtb0FL
* CountCache.java 1t/#ZT!X/
* "1_eZ `
* Created on 2007年1月1日, 下午5:01 4Y8/>uL
* n\&[^Q#b|
* To change this template, choose Tools | Options and locate the template under <<K G S
* the Source Creation and Management node. Right-click the template and choose ve_TpP
* Open. You can then make changes to the template in the Source Editor. "<x%kD
*/ LDHuf<`
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package com.tot.count; %g}ri8
import java.util.*; ]cLO-A
/** _M=
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* r`}')2
* @author Au08k}h<G
*/ uG@Nubdwuy
public class CountCache { n#,|C`2r
public static LinkedList list=new LinkedList(); l[mXbQd
/** Creates a new instance of CountCache */ x\!Q[
public CountCache() {} }-9
public static void add(CountBean cb){ }2;~':Mklz
if(cb!=null){ hb'S!N5m
list.add(cb); ` WIv|S
} PJLSDIeN
} wB}s>o\
} s0
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CountControl.java W>+\A"
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/* E c[-@5x
* CountThread.java ) *ocX)AE
* ^=@L(;Y
* Created on 2007年1月1日, 下午4:57 oF[l<OY4
* S*<+vIo
* To change this template, choose Tools | Options and locate the template under +]P??`,R;
* the Source Creation and Management node. Right-click the template and choose jh\L)a*
* Open. You can then make changes to the template in the Source Editor. :r*skV|
*/ tb#. Y
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package com.tot.count; v:kTZB
import tot.db.DBUtils; kKwb)i
import java.sql.*; A46z2
/** /pni_-l*
* J P'|v"
* @author dq[X:3i
*/ JJ_77i
public class CountControl{ QQ^P IQj
private static long lastExecuteTime=0;//上次更新时间 %7WGodlXW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ew8f7S[
/** Creates a new instance of CountThread */ k_$:?$
public CountControl() {} R:8\z0"L*
public synchronized void executeUpdate(){ W=j
Connection conn=null; dHjJLs_
PreparedStatement ps=null; |c,,*^
try{ =z`GC1]bL
conn = DBUtils.getConnection(); v.Wkz9
w}
conn.setAutoCommit(false); i|A0G%m] $
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YJi C}.4Q
for(int i=0;i<CountCache.list.size();i++){ 8V$pdz| [
CountBean cb=(CountBean)CountCache.list.getFirst(); ~kM# lh7At
CountCache.list.removeFirst(); vqDd][ n
ps.setInt(1, cb.getCountId()); KneCMFy
ps.executeUpdate();⑴ {z:aZ]QhKc
//ps.addBatch();⑵ _qwKFC
} 4 0as7.q
//int [] counts = ps.executeBatch();⑶ >;I$&
conn.commit(); z&x
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}catch(Exception e){ wJ
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e.printStackTrace(); O~Eju
} finally{ I29aja
try{ 8XFs)1s[
if(ps!=null) { V?x&.C2Z
ps.clearParameters(); Se*o{V3s$
ps.close(); .dqV fa
ps=null; vhe[:`=a
} A|3'9iL{9
}catch(SQLException e){} 36ygI0V_
DBUtils.closeConnection(conn); };{V]f 0
} DL$O274uZ
} <OF2\#Nh
public long getLast(){ T \Zf`.mt
return lastExecuteTime; wB%:RI,
} `1;m:,9
public void run(){ 2Fwp\I;
long now = System.currentTimeMillis(); tkQ#mipAj
if ((now - lastExecuteTime) > executeSep) { /Z':wu\
//System.out.print("lastExecuteTime:"+lastExecuteTime); \v|nRn,`-
//System.out.print(" now:"+now+"\n"); r57CyO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :xqhPr]e
lastExecuteTime=now; S.G"*'N
executeUpdate(); ,mkXUW
} wrtJ8O(
else{ \q2:1X|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~<
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} 2VB|a;Mo
} OFc Lh
} 6MsVV_/
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 K+2sq+3q
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类写好了,下面是在JSP中如下调用。 e+'PRVc
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<% Kyn[4Bu!?
CountBean cb=new CountBean(); |AgdD
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); V]4g-
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CountCache.add(cb); yHYqJ|t
out.print(CountCache.list.size()+"<br>"); R;XG2
CountControl c=new CountControl(); O$
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c.run(); 3
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out.print(CountCache.list.size()+"<br>"); Q:nBx[%
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