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: qB_s<cpn>
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CountBean.java dh6kj-^;Cf
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/* "AjC2P],
* CountData.java h@O\j&#
* '6NrL;
* Created on 2007年1月1日, 下午4:44 RICm$,
* R[\1Kk(Zo
* To change this template, choose Tools | Options and locate the template under y lczM^@
* the Source Creation and Management node. Right-click the template and choose Q]=/e7
* Open. You can then make changes to the template in the Source Editor. ?`xF>P]M
*/ N,XjZ26
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package com.tot.count; rQT%~oM:
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/** >CrrxiG
* +2:HgW
* @author N}nE9z5
*/ O&/nBHu\
public class CountBean { >ryA:TO{
private String countType; 2 ^"j]g>mj
int countId; ,(h-
/** Creates a new instance of CountData */ ^"I@ 8 k
public CountBean() {} w+')wyB
public void setCountType(String countTypes){ hC"'cUrcN
this.countType=countTypes; R%n*wGi_6b
} ]XlBV-@b
public void setCountId(int countIds){ 7=yM40
this.countId=countIds; ,OwTi:yDr
} b7^q(}qE
public String getCountType(){ qm/>\4eLt
return countType; +@fEw
} :](#W@r
public int getCountId(){ sM)1w-
return countId; :!t4.ko
} |H5GWZ
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} TtrO _D
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CountCache.java $s1/Rmw
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/* Zbre5&aU
* CountCache.java whw+
* m.ka%h$
* Created on 2007年1月1日, 下午5:01 Q'=7#_
* gp$]0~[tO
* To change this template, choose Tools | Options and locate the template under 0OG
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* the Source Creation and Management node. Right-click the template and choose *[
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* Open. You can then make changes to the template in the Source Editor. Zp[>[1@+
*/ 6`'g ${U
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package com.tot.count; q0ab]g+
import java.util.*; C=Fu1Hpb
/** qF(i1#
* M9fQ,<c<6
* @author 6:}n}q,V
*/ 4s%zvRu
public class CountCache { QPp31o.!5
public static LinkedList list=new LinkedList(); ~eP~c"L
/** Creates a new instance of CountCache */ JP"#9f
public CountCache() {} #"r_ 3
public static void add(CountBean cb){ f-i5tnh
if(cb!=null){ bYQ@!
list.add(cb); @b 17jmq{
} D,p2MBr
} 1jKj'7/K
} {G3Ok++hc
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CountControl.java 0#Us*:[6
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/* cr0/.Zv)
* CountThread.java Vr&
GsT
* >mvE[iXRG?
* Created on 2007年1月1日, 下午4:57 .%J<zqk-
* v0\M$@N[
* To change this template, choose Tools | Options and locate the template under P5G0fq7
* the Source Creation and Management node. Right-click the template and choose DsxNg
* Open. You can then make changes to the template in the Source Editor. |*ZM{$
*/ .#tA .%
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package com.tot.count; 5G2ueRVb
import tot.db.DBUtils; < <0[PJ
import java.sql.*; =v?V
/** YwH Fn+
* n87Uf$
* @author s+ *LVfau
*/ mV"F<G; H
public class CountControl{ v#g:]T
private static long lastExecuteTime=0;//上次更新时间 2\64~a^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 RFe>#o
/** Creates a new instance of CountThread */ Y@UW\d*'%I
public CountControl() {} &09~ D8f'
public synchronized void executeUpdate(){ d7g$9&/q
Connection conn=null; 46l*ui_
PreparedStatement ps=null; gL|
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try{ 01
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conn = DBUtils.getConnection(); ".AW
conn.setAutoCommit(false); kAUL7_>6X
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JB5%\
for(int i=0;i<CountCache.list.size();i++){ $@^\zg1n
CountBean cb=(CountBean)CountCache.list.getFirst(); 9ec#'i=
CountCache.list.removeFirst(); 5xUZeLj
ps.setInt(1, cb.getCountId()); ey<z#Q5+
ps.executeUpdate();⑴ aRn""3[
//ps.addBatch();⑵ fCs{%-6cP
} $b^ niL
//int [] counts = ps.executeBatch();⑶ -;
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conn.commit(); i 28TH
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}catch(Exception e){ K",Xe>
e.printStackTrace(); v'`qn
} finally{ %,S:^Rvv
try{ (IHR {m
if(ps!=null) { 8&+u+@H
ps.clearParameters(); :*l\j"fX5
ps.close(); tmoclK-
ps=null; ?a,`{1m0\
} F2(^OFh
}catch(SQLException e){} cF9ZnT.
DBUtils.closeConnection(conn); h3\(660>$
} p@DVy2,EY
} 3WGOftLzt
public long getLast(){ 5Em.sz;:8
return lastExecuteTime; gm:Y@6W
} u
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public void run(){ 2=7[r-*E
long now = System.currentTimeMillis(); :c}PW"0v
if ((now - lastExecuteTime) > executeSep) { VJr ~h
"[
//System.out.print("lastExecuteTime:"+lastExecuteTime); wB[
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//System.out.print(" now:"+now+"\n"); "K|':3n|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Bbb":c6w0
lastExecuteTime=now; E.*wNah"U
executeUpdate(); V^;lg[:
} 'wBOnGi6
else{ Qe9}%k6@E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7<8'7<X
} j\BtaC
} 4w 7vgB
} .",BLuce
//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 b?M. 0{"H
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类写好了,下面是在JSP中如下调用。 $`C$|9S
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<% Ms%C:KG
CountBean cb=new CountBean(); 5Ktll~+:#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -
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CountCache.add(cb); :de4Fje/4y
out.print(CountCache.list.size()+"<br>"); WdJeh:h
CountControl c=new CountControl(); ?WS.RB e2
c.run(); 3c`
out.print(CountCache.list.size()+"<br>");
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