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: a^_W}gzzd
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CountBean.java (EjlnG}5l
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/* ,/kZt!
* CountData.java g~U<0+&yw%
* cP\ZeG#<
* Created on 2007年1月1日, 下午4:44 !tb!%8{~
* VVcli*
* To change this template, choose Tools | Options and locate the template under 8|Ob7+
* the Source Creation and Management node. Right-click the template and choose <[w5M?n8
* Open. You can then make changes to the template in the Source Editor. hj{)6dBX%
*/ ouO9%)zv
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package com.tot.count; gk;hpO
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/** [WV&Y,E
* f>e0l'\
* @author hQ@#h`lS
*/ {&L^|X
public class CountBean { Fnay{F8z
private String countType; )l/
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int countId; 5>UQ 3hWo
/** Creates a new instance of CountData */ %Y"pVBc
public CountBean() {} ?uU_N$x
public void setCountType(String countTypes){ Jfo'iNOu
this.countType=countTypes; %dzO*/8cWo
} ]{|lGtK %
public void setCountId(int countIds){ Q [C26U
this.countId=countIds; $$EEhy
} 1OqVV?oz
public String getCountType(){ o+)y!
return countType; L=fy!R
} u /DE
public int getCountId(){ q*tGlM@R?
return countId; bZ:xH48MY
} F1BXu@~e(
} Ni|MTE]~
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CountCache.java Xfbr;Jt"<
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/* C+"c^9[
* CountCache.java HF"TS*
* IP@3R(DS%
* Created on 2007年1月1日, 下午5:01 U$3DIJVI
* 1Kr$JIcd
* To change this template, choose Tools | Options and locate the template under DuT6Od/f
* the Source Creation and Management node. Right-click the template and choose sv!v`zh
* Open. You can then make changes to the template in the Source Editor. gsUF\4A(J
*/ !YI<A\P
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package com.tot.count; Zu~w:uNmU
import java.util.*; u&[L!w
/** -7'|&zP
* bfm+!9=9S
* @author 0pG +yec
*/ "K$c 9Z8
public class CountCache { &[
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public static LinkedList list=new LinkedList(); X6_
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/** Creates a new instance of CountCache */ uA;#*eiA/
public CountCache() {} R MOs1<D
public static void add(CountBean cb){ VW*?(,#j{
if(cb!=null){ A?$-Uqb"
list.add(cb); Dsn=fht
} m*CW3y{n)
} }0Uh<v@
} /8nUecr
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CountControl.java _0FMwC#DY
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/* D$>&K&
* CountThread.java *wY+yoj
* iH@u3[w
* Created on 2007年1月1日, 下午4:57 nnvS.s`O
* !]Qk?T~9-
* To change this template, choose Tools | Options and locate the template under IG{Me
* the Source Creation and Management node. Right-click the template and choose f6Lc"b3s1
* Open. You can then make changes to the template in the Source Editor. #5kclu%L$
*/ *uf)t,%
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package com.tot.count; GB<.kOGQ[
import tot.db.DBUtils; { Ie~MW
import java.sql.*; S'W,AkT
/** d*VvQU8C
* ryw%0H18
* @author N)Q.P'`N
*/ >HRNB&]LdP
public class CountControl{ ')~V=F
private static long lastExecuteTime=0;//上次更新时间 t'0&n3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8 hhMuh
/** Creates a new instance of CountThread */ f~PS'I_r
public CountControl() {} 7R
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public synchronized void executeUpdate(){ NZ&ZK@h}.
Connection conn=null; UKV<Ye|
PreparedStatement ps=null; x?lRObHK
try{ `LLmdm 6i
conn = DBUtils.getConnection(); _|cSXZ|
conn.setAutoCommit(false); TQ:5@1aT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); k;`1Ia
for(int i=0;i<CountCache.list.size();i++){ 85)C7tJ-g
CountBean cb=(CountBean)CountCache.list.getFirst(); F$jy~W_
CountCache.list.removeFirst(); }{j@q~w>$
ps.setInt(1, cb.getCountId()); Mis B&Ok`k
ps.executeUpdate();⑴ r@]`#PL
//ps.addBatch();⑵ ,x!r^YO=
} FG+pR8aA$
//int [] counts = ps.executeBatch();⑶ db8vm4
conn.commit(); ^Y;,cLXJ
}catch(Exception e){ 1gcWw, /
e.printStackTrace(); ::'Y07
} finally{ ~piE$"]&
try{ HeO&p@
if(ps!=null) { RticGQy&5
ps.clearParameters(); 5h^BXX|Y*
ps.close(); 1?^
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ps=null; Ejr'Yzl3_
} /kK!xe
}catch(SQLException e){} q~5zv4NX
DBUtils.closeConnection(conn); bZ:+q1
D
} *PV7s
} \`["IkSg7
public long getLast(){ X>Q4 4FV!
return lastExecuteTime; K(PSGlI f
} ]!P8 {xmb@
public void run(){ S]|sKY
long now = System.currentTimeMillis(); rc<Ix
if ((now - lastExecuteTime) > executeSep) { d4ld-y
//System.out.print("lastExecuteTime:"+lastExecuteTime); tKcC{
//System.out.print(" now:"+now+"\n"); }CMGK{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZzTkEz >
lastExecuteTime=now; zh0T3U0D
executeUpdate(); <2%9O;bV[
} F[%k;aJ
else{ \P9ms?((A
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8Dtpb7\o
} r-L& ee
} +WR?<*_
} oQ/T5cOj
//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 oIx|)[
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类写好了,下面是在JSP中如下调用。 Vp~ cN
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<% v<g~EjzCf
CountBean cb=new CountBean(); H25Qx;(dTk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); CueC![pj
CountCache.add(cb); Sy1O;RTn`
out.print(CountCache.list.size()+"<br>"); SiaW; ks
CountControl c=new CountControl(); /5"T46jD
c.run(); d0ht*b
out.print(CountCache.list.size()+"<br>"); vY|YqWt
%>