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: ER5Q` H
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CountBean.java dWD,iO_"@
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/* 6FSw_[ )
* CountData.java .2
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* ~A8lvuw3
* Created on 2007年1月1日, 下午4:44 /~7H<^}
* :c)<B@NqNo
* To change this template, choose Tools | Options and locate the template under 30>TxL=&
* the Source Creation and Management node. Right-click the template and choose Eg-b5Z);
* Open. You can then make changes to the template in the Source Editor. #Opfc8pm'
*/ '[Oi_gE.
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package com.tot.count; qvYYKu
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/** ~uC4>+dk
* /l+x&xYD
* @author 92Ar0j]
*/ M|d[iaM,
public class CountBean {
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private String countType; S;ulJ*qv
int countId; /gy;~eB01
/** Creates a new instance of CountData */ Kz3u
public CountBean() {} &O0+\A9tP
public void setCountType(String countTypes){ 1V+1i)+
this.countType=countTypes; s^V8FH
} }~QB2&3
public void setCountId(int countIds){ \U !<-
this.countId=countIds; 4N$svA
} .[2MPjg
public String getCountType(){ f[.hN
return countType; s7xRry
} Q(]-\L'
public int getCountId(){ &1Cq+YpI
return countId; d'[aOH4}
} 0M8JE9 Kx
} K:y q^T7
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CountCache.java Vg
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/* i+&="Z@
* CountCache.java AF3t#)q
* M8cLh!!
* Created on 2007年1月1日, 下午5:01 _"0n.JQg
* y\0^c5}
* To change this template, choose Tools | Options and locate the template under K7f-g]Ibdn
* the Source Creation and Management node. Right-click the template and choose |!!E5osXq
* Open. You can then make changes to the template in the Source Editor. /mD KQ<
*/ (sqS(xIY
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package com.tot.count; d}l^yln
import java.util.*; cC}s5`
/** ['R=@.
* hLm9"N'Pf
* @author B. P64"w
*/ "BFW&<1
public class CountCache { '|XP}V0I
public static LinkedList list=new LinkedList(); e/Q[%y.X
/** Creates a new instance of CountCache */ 5\4>H6
public CountCache() {} o~4n8
public static void add(CountBean cb){ !zJ.rYZ=g`
if(cb!=null){ ~-:CN(U
list.add(cb); &PgdCijGq;
} v$tS2N2
} cF(9[8c{
} 4tuEC-oh
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CountControl.java E?9_i
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/* 8OFrW.>[
* CountThread.java ZcWl{e4
* Y}?@Pm drz
* Created on 2007年1月1日, 下午4:57
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* rk. UW
* To change this template, choose Tools | Options and locate the template under \FKIEg+(2
* the Source Creation and Management node. Right-click the template and choose 6op\g].P
* Open. You can then make changes to the template in the Source Editor. RDqC$Gu
*/ /GeS(xzQ
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package com.tot.count; ,@!d%rL:4]
import tot.db.DBUtils; S~TJF}[k^6
import java.sql.*; Z^~6pH\
/** %@xYg{
* KdR&OBm
* @author <.v6w*+{/
*/ n9J>yud|
public class CountControl{ [KE4wz+s{
private static long lastExecuteTime=0;//上次更新时间 BuvBSLC~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u?J(l)gd
/** Creates a new instance of CountThread */ CD tYj
public CountControl() {} Q-au)R,
public synchronized void executeUpdate(){ -[`W m7en
Connection conn=null; 5:PZ=jPR
PreparedStatement ps=null; B}FF |0<
try{ z::2O/ho
conn = DBUtils.getConnection(); C=b5[, UCB
conn.setAutoCommit(false); 785iY865
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r9t{/})A
for(int i=0;i<CountCache.list.size();i++){ *FE<'+%
CountBean cb=(CountBean)CountCache.list.getFirst(); [ho'Pc3A<
CountCache.list.removeFirst(); XM 7zA^-
ps.setInt(1, cb.getCountId()); WcJ{}V9
ps.executeUpdate();⑴ /<2_K4(-{4
//ps.addBatch();⑵ e=R}
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} :Aa^afjJw
//int [] counts = ps.executeBatch();⑶ lxz %bC@
conn.commit(); e5/_Vga
}catch(Exception e){ .o8Gi*PEY
e.printStackTrace(); 1k~jVC2VA
} finally{ 8xv\Zj +
try{ o{hKt?
if(ps!=null) { i:$g1
ps.clearParameters(); .)GVb<w
ps.close(); >mV""?r]
ps=null; SeTU`WLEm
} evR= Z\
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}catch(SQLException e){} W6iIL:sp
DBUtils.closeConnection(conn); GkC88l9z
} M@K[i*e
} a&[n Vu+
public long getLast(){ BY d3 rI
return lastExecuteTime; ={Hbx>p
} Sce9R?II
public void run(){ Zk[#BUA
long now = System.currentTimeMillis(); 5jLDe~
if ((now - lastExecuteTime) > executeSep) { t(yv
//System.out.print("lastExecuteTime:"+lastExecuteTime); [~o3S$C&7
//System.out.print(" now:"+now+"\n"); [n"<(~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v uP1gem
lastExecuteTime=now; '8JaD6W9S
executeUpdate(); 'YeJGzsJp
} OG+ $F
else{ b2Hpuej
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d]^i1
} DI RCP=5
} <f6Oj`{f4
} O`=Uq0Vv
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 FdqUv%(Em
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类写好了,下面是在JSP中如下调用。 40E[cGz$*
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<% <*+MBF
CountBean cb=new CountBean(); ivq4/Y]-X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pDLo`F}A
CountCache.add(cb); >']H)c'2
out.print(CountCache.list.size()+"<br>"); 9<a yQ*
CountControl c=new CountControl(); 7ou^wt+%
c.run(); iI1t
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out.print(CountCache.list.size()+"<br>"); Ame%:K!t
%>