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: :9(w~bB9$
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CountBean.java P ?96;
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/* CK_\K,xVT
* CountData.java 3$BO=hI/-
* jS5K:yx<
* Created on 2007年1月1日, 下午4:44 A0Q1"b=
* E.-2 /'i
* To change this template, choose Tools | Options and locate the template under )}vUYTU1
* the Source Creation and Management node. Right-click the template and choose tf1Y5P$
* Open. You can then make changes to the template in the Source Editor. Mko,((>I1
*/ |uX&T`7?-
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package com.tot.count; AJ6O>Euq
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/** I*mBU^<9V
* =/4}!B/
* @author 84s:cO
*/ 2P{! n#"
public class CountBean { \lyHQ-gWhc
private String countType; BZjL\{IW
int countId; W9bpKmc
/** Creates a new instance of CountData */ 6)FM83zk)K
public CountBean() {} pBn;:
public void setCountType(String countTypes){ yA`,ns&n
this.countType=countTypes; :K(+ KN(
} RER93:(
public void setCountId(int countIds){ k9c`[M
this.countId=countIds; Z'm( M[2K
} |>-0q~
public String getCountType(){ }/g1
return countType; v[a4d&P
} ZB5NTNf>
public int getCountId(){ GB>T3l"
return countId; akwS;|SZ
} h(^[WSa
} w"A>mEex<
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CountCache.java 9Z3Vf[n5\
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/* ;)sC{ "Jb
* CountCache.java H{_6e6`e.
* fvG4K(
* Created on 2007年1月1日, 下午5:01 L_!}R
* :%U
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* To change this template, choose Tools | Options and locate the template under w2K>k/v{-
* the Source Creation and Management node. Right-click the template and choose ytV4qU82G
* Open. You can then make changes to the template in the Source Editor. t3!~=U
*/ ~$7YEs)
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package com.tot.count; u0$}VO5/a
import java.util.*; lvUWs
/** ESe$6)P
* KnK\X>:
* @author } OkK@8?0O
*/ /EL3Tt
public class CountCache { ?Uhjyi
public static LinkedList list=new LinkedList(); EclsOBg
/** Creates a new instance of CountCache */ 3p'(E\VJ
public CountCache() {} PW9tZx#
public static void add(CountBean cb){ lW]&a"1$
if(cb!=null){ ZZ>(o
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list.add(cb); u#3Cst8Y
} NF7+Gp6?q
} $@[Mo
} R5<:3tk=X
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CountControl.java e^hI[LbNC
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/* p
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* CountThread.java \r&(l1R
* 'tVe#oI
* Created on 2007年1月1日, 下午4:57 Wa%p+(\<uB
* X C'|
* To change this template, choose Tools | Options and locate the template under 6h\; U5
* the Source Creation and Management node. Right-click the template and choose sT91>'&
* Open. You can then make changes to the template in the Source Editor. 5J3K3
*/ >~T2MlRux
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package com.tot.count; yeV|j\TJI.
import tot.db.DBUtils; ?jnbm'~S
import java.sql.*; \K:?#07Wj4
/** "}uV=y
* Ul|htB<1:
* @author K!gocNOf
*/ t5S!j2E
public class CountControl{ KU_""T
private static long lastExecuteTime=0;//上次更新时间 tCu9
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 D]K?ntS[*
/** Creates a new instance of CountThread */ |1/?>=dDm
public CountControl() {} :A,7D(H|
public synchronized void executeUpdate(){ ~B`H5#
Connection conn=null; 1*B'o<?P1
PreparedStatement ps=null; d*:J0J(
try{ PB@jh}
conn = DBUtils.getConnection(); M+L0 X$}NZ
conn.setAutoCommit(false); "GAKi}y">v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); . 3xf!E*
for(int i=0;i<CountCache.list.size();i++){ ~Ecx>f4nX
CountBean cb=(CountBean)CountCache.list.getFirst(); ?lIh&C8]X
CountCache.list.removeFirst(); 1xsB@D
ps.setInt(1, cb.getCountId()); T?D]]x
ps.executeUpdate();⑴ p$6L_
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//ps.addBatch();⑵ EOf*1/Ih
} qvRs1yr?q
//int [] counts = ps.executeBatch();⑶ tSaD=# v
conn.commit(); 1(
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}catch(Exception e){ H(Ad"1~.#
e.printStackTrace(); _(KzjOMt
} finally{ KocNJ
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try{ fyv S1_
if(ps!=null) { @Sz7*p
ps.clearParameters(); ,L8(Vo`-
ps.close(); Ewo6Q){X
ps=null; vH]2t.\
} A*? Qm
}catch(SQLException e){} Kuh)3/7
DBUtils.closeConnection(conn); p[D,.0SuC
} l/bZE.GJ
} K )9f\1\
public long getLast(){ V_T~5%9Fy
return lastExecuteTime; qWI8 >my11
}
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public void run(){ Gk<6+.c~
long now = System.currentTimeMillis(); 4pFoSs?\
if ((now - lastExecuteTime) > executeSep) { "%+9p6/
//System.out.print("lastExecuteTime:"+lastExecuteTime); \0^Je>-:U
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k
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lastExecuteTime=now; }yM!o`90
executeUpdate(); nkz^^q`5l7
} S!7|vb*ko
else{ \2)~dV:6+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'tq4-11xB
} AXpyia7nU
} P? LpI`f
} \xOv 9(
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 l`*R !\
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类写好了,下面是在JSP中如下调用。 o>\epQt~/p
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<% ,}$[;$ye
CountBean cb=new CountBean(); +K"d\<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2sT\+C&H
CountCache.add(cb); @5TJ]=
out.print(CountCache.list.size()+"<br>"); 2Xp?O+b#"O
CountControl c=new CountControl(); A)D1
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c.run(); Us8nOr>5
out.print(CountCache.list.size()+"<br>"); ]Hrw$\Ky
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