Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 X^Y9T`mQ}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 [bv@qBL
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 `5-#M/J
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 JJ?ri,
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分页支持类: -^H5z+"^
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java代码: AtlR!IEUb
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package com.javaeye.common.util; eH
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import java.util.List; a{HgIQg_>R
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publicclass PaginationSupport { 1vs>2` DLa
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publicfinalstaticint PAGESIZE = 30; W4*BR_H&*
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privateint pageSize = PAGESIZE; 0a6@HwO
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privateList items; }r~l72
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privateint totalCount; bNjaCK<
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privateint[] indexes = newint[0]; Ym{%"EB
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privateint startIndex = 0; X,EYa>RSy_
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public PaginationSupport(List items, int uU(G_E ?
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totalCount){ "8iiRzt#
setPageSize(PAGESIZE); x]><}!\<&
setTotalCount(totalCount); n+\Cw`'<H
setItems(items); W|rFl]~a
setStartIndex(0); f93rY<
} @~#79B"9&
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public PaginationSupport(List items, int _HHJw""j
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totalCount, int startIndex){ Hrg=sR
setPageSize(PAGESIZE); JNM@Q
setTotalCount(totalCount); /zG-\e U
setItems(items); AV[P QI
setStartIndex(startIndex); BRU9LS
} iWN.3|r
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public PaginationSupport(List items, int <W=[
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totalCount, int pageSize, int startIndex){ ]i,Mq
setPageSize(pageSize); Q$.V:#
setTotalCount(totalCount); |6(qg5"
setItems(items); H&yFSz}6a
setStartIndex(startIndex); :S99}pgY
} 4&]To@>
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publicList getItems(){ 'tV"^KQHI
return items; z@%/r~?|
} ^=izqh5S
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publicvoid setItems(List items){ CdzkMVH
this.items = items; U8WHE=Kk\h
} # McK46B z
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publicint getPageSize(){ iUxDEt[t*
return pageSize; lN)Y
} VO @
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publicvoid setPageSize(int pageSize){ ~aqT~TL_
this.pageSize = pageSize; }/7.+yD
} h$aew63
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publicint getTotalCount(){ nv_m!JG7
return totalCount; +YQ~t,/
} mV**9-"
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publicvoid setTotalCount(int totalCount){ w8ZHk?:
if(totalCount > 0){ j h1 bn
this.totalCount = totalCount; L.IoGUxD
int count = totalCount / >ggk>s|
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pageSize; ~C/Yv&58
if(totalCount % pageSize > 0) [U%ym{be^
count++; ]5o0
indexes = newint[count]; )8x:x7?
for(int i = 0; i < count; i++){ 0.J1!RIK/
indexes = pageSize * E'&OOEMN-
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} e9z$+h
}else{ cotxo?)Zv
this.totalCount = 0; u_}`y1Xu#
} 5eiZs
} F.~n
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publicint[] getIndexes(){ .q5J^/kr
return indexes; m0xJ05Zx
} _KSfP7VU
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publicvoid setIndexes(int[] indexes){ iXUWIgr
this.indexes = indexes; tsTR2+GZS
} ShL1'Z}^{
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publicint getStartIndex(){ 71k!k&Im
return startIndex; A0cM(w{7_
} fnLR
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publicvoid setStartIndex(int startIndex){ x !#Ma
if(totalCount <= 0) Wphe%Of
this.startIndex = 0; 2gQY8h8
elseif(startIndex >= totalCount) yPf?"W
this.startIndex = indexes b34zhZ
}Kvh`@CiJ
[indexes.length - 1]; l 8O"w&
elseif(startIndex < 0) d u.HSXK
this.startIndex = 0; P1(8U%
else{ =8$|_
this.startIndex = indexes mV6#!_"
52>[d3I3
[startIndex / pageSize]; !7A"vTs
} aqcFY8b
'
} tP}Xhn`
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publicint getNextIndex(){ 1U717u
int nextIndex = getStartIndex() + fC=fJZU7$
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pageSize; Jy]FrSm^
if(nextIndex >= totalCount) 6!4';2Q
return getStartIndex(); BhqhyX\D&y
else ?cqicN.+6
return nextIndex; >pgQb9
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} 8# 6\+R
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publicint getPreviousIndex(){ Q{H17]W
int previousIndex = getStartIndex() - LiiK3!^i
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pageSize; _aVJ$N.
if(previousIndex < 0) /uK)rG
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return0; W\HLal
else ^Ku\l #B
return previousIndex; +2-
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} Bx+d3
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} V]r hr
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抽象业务类 BTOA &Ag
java代码: cN62M=**
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/** zT$0xj8
* Created on 2005-7-12 cZ^wQ5=
*/ P=c?QYF
package com.javaeye.common.business; :qBGe1Sv(
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import java.io.Serializable; _Q>
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import java.util.List; FH4u$g+
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import org.hibernate.Criteria; 6*sw,sU[y
import org.hibernate.HibernateException; Dzo{PstM%
import org.hibernate.Session; 'c#IMlv
import org.hibernate.criterion.DetachedCriteria; i[PvDv"n
import org.hibernate.criterion.Projections; zkd3Z$Ce
import q1STRYb
J`W-]3S#
org.springframework.orm.hibernate3.HibernateCallback; ~xw5\Y^
import n|6?J_{<b>
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org.springframework.orm.hibernate3.support.HibernateDaoS sA3UeTf
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upport; $.wA?`1aSk
}~rcrm.
import com.javaeye.common.util.PaginationSupport; s_xV-C#q@
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public abstract class AbstractManager extends !5&%\NSv
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HibernateDaoSupport { ]Dh1~k.Kp
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privateboolean cacheQueries = false; RE 9nU%!
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privateString queryCacheRegion; V'j@K!)~xR
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publicvoid setCacheQueries(boolean *!Y-!
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cacheQueries){ D;jK/2
this.cacheQueries = cacheQueries; ~\[?wN
} e{0L%%2K
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publicvoid setQueryCacheRegion(String q4k.f_{
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queryCacheRegion){ nS.2C>A
this.queryCacheRegion = 5/ * >v
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queryCacheRegion; -6`;},Yr
} wd wp9 r
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publicvoid save(finalObject entity){ doM?8C#`
getHibernateTemplate().save(entity); 1[s0Lz
} T9?54r
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publicvoid persist(finalObject entity){ f?^S bp
getHibernateTemplate().save(entity); R*bmu
} 7}%H2$Do
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publicvoid update(finalObject entity){ ?mU\
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getHibernateTemplate().update(entity); ^)0 9OV+hF
} AkA!:!l
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publicvoid delete(finalObject entity){ #ib^Kg
getHibernateTemplate().delete(entity); 'M N1A;IJ
} *ik/p
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publicObject load(finalClass entity, mxp Y&Y
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finalSerializable id){ 8W -@N
return getHibernateTemplate().load 7@l<?
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(entity, id); O%g\B8;
} uR_F,Mp?%u
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publicObject get(finalClass entity, >DP:GcTG
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finalSerializable id){ *
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return getHibernateTemplate().get wf9z"B
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(entity, id); !d8A
} <2<87PU
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publicList findAll(finalClass entity){ ^npJUa
return getHibernateTemplate().find("from pM2a(\K,k^
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" + entity.getName()); |=5/Rax^
} iM5vrz`n
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publicList findByNamedQuery(finalString 2f,2rW^i
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namedQuery){ %|+E48
return getHibernateTemplate kg>>D
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().findByNamedQuery(namedQuery); CDdkoajBa
} f$F*3
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publicList findByNamedQuery(finalString query, Y7SacRO
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finalObject parameter){ e:-8k_0|
return getHibernateTemplate *e/K:k
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().findByNamedQuery(query, parameter); Vmi{X b]<
} lZWX7FO'
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publicList findByNamedQuery(finalString query, s9j7Psd
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finalObject[] parameters){ >/^#Drwb!i
return getHibernateTemplate YnTB&GPxl
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().findByNamedQuery(query, parameters); NlF}{
} `xz&Scil
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publicList find(finalString query){ \Fb| {6+
return getHibernateTemplate().find 0KvVw rWJ
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(query); ^b-18 ~s
} Q0cRH"!:
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publicList find(finalString query, finalObject :c]`D>
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parameter){ ^g>1U5c
return getHibernateTemplate().find !GK$[9
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(query, parameter); Lm%GR[tyQ
} -?a<qa?$
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public PaginationSupport findPageByCriteria )TmtSSS
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(final DetachedCriteria detachedCriteria){ "Ty/k8?
return findPageByCriteria buMqF-j
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); H+C6[W=
} F%/h*
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public PaginationSupport findPageByCriteria BavO\{J#|0
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(final DetachedCriteria detachedCriteria, finalint /Cr/RG:OX
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startIndex){ V'gw\mcb
return findPageByCriteria *cv}*D
*r,b=8|
(detachedCriteria, PaginationSupport.PAGESIZE, (lH,JX`$a
8v92Ng7
startIndex); 0E/:|k
} m"/g7w4N
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public PaginationSupport findPageByCriteria xytr2V ]aV
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(final DetachedCriteria detachedCriteria, finalint 9'~-U
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pageSize, +a+`Z>
finalint startIndex){ u<tk G B
return(PaginationSupport) ) g1a'G
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getHibernateTemplate().execute(new HibernateCallback(){ }IkQA#4$
publicObject doInHibernate edC4BHE
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(Session session)throws HibernateException { 8Jr?ZDf`
Criteria criteria = z(HaRB3l
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detachedCriteria.getExecutableCriteria(session); ;3ft1
int totalCount = -8Ti*:
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((Integer) criteria.setProjection(Projections.rowCount 9s$U%F6}
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()).uniqueResult()).intValue(); o|8`>!hF
criteria.setProjection "4xfrlOc
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(null); /Wj,1WX~
List items = ^HA
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c+' =hR[
criteria.setFirstResult(startIndex).setMaxResults Sfjje4R
e 9$C#D>D
(pageSize).list(); i8pU|VpA
PaginationSupport ps = O}ejWP8>
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new PaginationSupport(items, totalCount, pageSize, 2 YxT MT
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startIndex); Es5p}uh.[Y
return ps; wzWbB2Mb5
} S 01wwZ
}, true); fZWGn6$
} .m4;^S2cO
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public List findAllByCriteria(final GUB`|is^
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DetachedCriteria detachedCriteria){ p='-\M74K
return(List) getHibernateTemplate .V'V:;BE%
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().execute(new HibernateCallback(){ jFG0`n}I
publicObject doInHibernate F
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(Session session)throws HibernateException { c@m5~
Criteria criteria = 76fIC
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detachedCriteria.getExecutableCriteria(session); |1=
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return criteria.list(); 6)gd^{
} 6gO9 MQY
}, true); vq'c@yw;
} V L( <
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public int getCountByCriteria(final 7Hw<ojkt
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DetachedCriteria detachedCriteria){ xBnbF[
Integer count = (Integer) {y^3> 7
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getHibernateTemplate().execute(new HibernateCallback(){ D vkxI<Xa
publicObject doInHibernate q`|CrOzO
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(Session session)throws HibernateException { M@UVpQwgv
Criteria criteria = j0-McLc
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detachedCriteria.getExecutableCriteria(session); \&xl{64
return Bn wzcl
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criteria.setProjection(Projections.rowCount 3HV%4nZLf
<!^
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()).uniqueResult(); :Waox"#=g
} x ,/TXTZ6
}, true); gz#4{iT~
return count.intValue(); +RZ~LA\+
} JHV)ZOO
} Sq]pQ8
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用户在web层构造查询条件detachedCriteria,和可选的 Gy29MUF
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6Y*;{\Rd
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PaginationSupport的实例ps。 HZJL/=;
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ps.getItems()得到已分页好的结果集 @|-OJ4[5
ps.getIndexes()得到分页索引的数组 $Rtgr{ {;"
ps.getTotalCount()得到总结果数 $< %B#axL
ps.getStartIndex()当前分页索引 {aq9i
ps.getNextIndex()下一页索引 ZXiRw)rM
ps.getPreviousIndex()上一页索引 X~U >LLr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @s*,xHE
iw]k5<qKj
一下代码重构了。 /Bv#) -5
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我把原本我的做法也提供出来供大家讨论吧: I*)VZW
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首先,为了实现分页查询,我封装了一个Page类: 0&w0aP`Y
java代码: Y*YFB|f?
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/*Created on 2005-4-14*/ mf$j03tu
package org.flyware.util.page; 649 !=
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/** 'imU`zeo
* @author Joa {[OwMk
* IM(u<c$
*/ E%pz9gcSx
publicclass Page { UZxmhsv
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/** imply if the page has previous page */ 5G*II_j
privateboolean hasPrePage; C8b''9t.
z/|BH^Vw
/** imply if the page has next page */ K b(9)Re
privateboolean hasNextPage; oN,s.Of
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/** the number of every page */ 1"E\C/c
privateint everyPage; l gq=GHW
LJuW${Y
/** the total page number */ g`Md80*Zfk
privateint totalPage; }[=YU%[o:
;bjnL>eW
/** the number of current page */ <|F-Dd
privateint currentPage; YMB~[]$V<
#+jUhxq
/** the begin index of the records by the current gY5l.&
McP.9v}H0_
query */ vDDljQXw4
privateint beginIndex; 4M`Xrfwm'[
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/** The default constructor */ Wc4vCVw
public Page(){ W<'<'z5
sBjXE>_#)
} ~"7J}[i5
6Z c)0I'
/** construct the page by everyPage )/Y~6A9>
* @param everyPage g9V.13k
* */ _}=E^/;(
public Page(int everyPage){ i?>Hr|
this.everyPage = everyPage; Rc9<^g`
} [thboP.?
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/** The whole constructor */ xZ ;bMxZ
public Page(boolean hasPrePage, boolean hasNextPage, > V%Q O>C
JMsHK,(
*{[d%B<lp
int everyPage, int totalPage, DrS?=C@
int currentPage, int beginIndex){ *zQOJsg"e
this.hasPrePage = hasPrePage; In(NF#
this.hasNextPage = hasNextPage; M,..Kw/ }~
this.everyPage = everyPage; {hd-w4"115
this.totalPage = totalPage; DTy/jaK
this.currentPage = currentPage; (#u{ U=
this.beginIndex = beginIndex; !;WbOnLP
} =]KIkS 3
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/** cjY@Ot*i$
* @return r$DZkMue
* Returns the beginIndex. s=/^lOOO
*/ 4x]NUt
publicint getBeginIndex(){ 6/7F">@j
return beginIndex; -tP.S1D
} A$m<@%Sz
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/** FO^24p
* @param beginIndex LUul7y'"
* The beginIndex to set. k~|ZO/X@l%
*/ BhkAQEsWTQ
publicvoid setBeginIndex(int beginIndex){ G5umeqYC
this.beginIndex = beginIndex; )0F^NU
} /j
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Sw
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/** f?m5pax|
* @return T#N80BH[
* Returns the currentPage. 6vWii)O.D
*/ l#ygb|=x
publicint getCurrentPage(){ '\'7yN'
return currentPage; `skH-lk,
} PL!tk^;6-
s
kY0 \V
/** 2<m
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* @param currentPage 8E-Ip>{>
* The currentPage to set. 7YD\ !2b
*/ !xH,y
publicvoid setCurrentPage(int currentPage){ 8E=vR 8
this.currentPage = currentPage; M;PlSb
} o[imNy~ ~
*V<)p%l.
/** D/*vj|
* @return 8z0Hx
* Returns the everyPage. +> ^[W~[2
*/ Ga?UHw~
publicint getEveryPage(){ Es:5yX!
return everyPage; "V:XhBG?
} @21u I{
n }TTq6B
/** KG-UW
* @param everyPage P2 |}*h5(
* The everyPage to set. iPz1eUj
*/ a0)vvo=bz
publicvoid setEveryPage(int everyPage){ zQ=aey%
this.everyPage = everyPage; <BQ%8}
} z3ZuC{
#'#4hJ*YC
/** P mC82"
* @return \2(MpB\_6!
* Returns the hasNextPage. A?\h|u<
*/ 2,+@#q
publicboolean getHasNextPage(){ .5Q5\qc=
return hasNextPage; &8zk3
} rT o%=0P
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/** +7`u9j.
* @param hasNextPage gp%tMTI1
* The hasNextPage to set. Yo>%s4_,
*/ Qz'O{f
publicvoid setHasNextPage(boolean hasNextPage){ rffVfw
this.hasNextPage = hasNextPage; ws#hhW3qK
} B6-AIPb
NT'Ie]|
/** H+nr5!`kz
* @return kg zwlKK
* Returns the hasPrePage. DrW/KU,{+(
*/ *
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publicboolean getHasPrePage(){ {c.}fyN
return hasPrePage; F>p%2II/
} $cyLI+uz|
~_(!}V
/** ^.nwc#
* @param hasPrePage v\J!yz
* The hasPrePage to set. D
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*/ h<t<]i'
publicvoid setHasPrePage(boolean hasPrePage){ \ro~-n+ o
this.hasPrePage = hasPrePage; Vx0MG{vG1
} A)= X?x
avF&F
/** 'U0I.x(
* @return Returns the totalPage. .*7UT~o=CS
* -d)n0)9
*/ ?0%TE\I8
publicint getTotalPage(){ -ix1<e
return totalPage; *03/:q ^(
} \ \}/2#1=c
kweTK]mT
/** I@M^Wu]wW
* @param totalPage Z!eq /
* The totalPage to set. 4TE ?mh}
*/ ~{Bi{aK2
publicvoid setTotalPage(int totalPage){ .)zISa*Xy
this.totalPage = totalPage; XOU$3+8q5
} $ 3B?
Z$XpoDbOy
} ~=ys~em e
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 W10fjMC}^
:n9^:srGZH
个PageUtil,负责对Page对象进行构造: `aycYoD
java代码: TMsoQ82
#Q7$I.O]
qQvb;jO
/*Created on 2005-4-14*/ Yk?q7xuT
package org.flyware.util.page; 1?\ Y,+
ulM&kw.4i
import org.apache.commons.logging.Log; $twF93u$
import org.apache.commons.logging.LogFactory; X+8p2xSO|
qT @IY)e
/** s3 $Q_8H
* @author Joa Q$j48,e
* c"1d#8J
*/ (=rv `1
publicclass PageUtil { MNC!3d(D\R
W|U1AXU7/
privatestaticfinal Log logger = LogFactory.getLog d2sq]Q
Q;nr=f7Ys
(PageUtil.class); wP"|$HN
fM.|#eLi
/** \
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* Use the origin page to create a new page =i?,y +<
* @param page ^j}sS!p
* @param totalRecords /|AuI qW
* @return <Q)}
*/ f4}6$>)
publicstatic Page createPage(Page page, int #jiqRhm
:`1g{8.+
totalRecords){ *'-^R9dN.S
return createPage(page.getEveryPage(), [bJnl>A
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page.getCurrentPage(), totalRecords); 7:'>~>'
} <t{AY^:r
IxBO$2
/** |3ETF|)?
* the basic page utils not including exception _Qc\v0%
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handler _1Gut"!{\
* @param everyPage S\gP= .G
* @param currentPage z-gG(
* @param totalRecords s;$TX30 4
* @return page va2A@U
*/ _\PoZ|G4y
publicstatic Page createPage(int everyPage, int >]8.xkQq
L-{r*ccIW
currentPage, int totalRecords){ /j@ `aG(a
everyPage = getEveryPage(everyPage); {`CWzk?
currentPage = getCurrentPage(currentPage); RGI6W{\
int beginIndex = getBeginIndex(everyPage, I]1Hi?A2
|9Ks13?Ck
currentPage); Qp&ySU8
int totalPage = getTotalPage(everyPage,
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<OSvRWP)
totalRecords); {
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boolean hasNextPage = hasNextPage(currentPage, ld:alEo
+ Z2<spqG
totalPage); =2)t1 H
boolean hasPrePage = hasPrePage(currentPage); qFbUM;
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returnnew Page(hasPrePage, hasNextPage, }h h^U^ia
everyPage, totalPage, $50"3g!Y
currentPage, <dPxy`_
~c$ts&Cl
beginIndex); Jd"s~n<>K
} h!CX`pBM
$:
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privatestaticint getEveryPage(int everyPage){ ~7WXjVZ
return everyPage == 0 ? 10 : everyPage; rGGepd
} fYM6wYJ
9Ru%E>el-
privatestaticint getCurrentPage(int currentPage){ E?4@C"Na
return currentPage == 0 ? 1 : currentPage; ai
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} -7z y
@"Fp;Je\bN
privatestaticint getBeginIndex(int everyPage, int 7 P^{*!
1$D`Z/N"A
currentPage){ ]O=S2Q
return(currentPage - 1) * everyPage; G,|]a#w&v.
} 2*wO5v
O| 6\g>ew
privatestaticint getTotalPage(int everyPage, int f"<@6Axq
39aCwhh7v
totalRecords){ 3kqV_Pjg
int totalPage = 0; bZay/ Zkj
&}6ES{Nr8
if(totalRecords % everyPage == 0) >{qK]xj
totalPage = totalRecords / everyPage; 3 [)s;e
else 0Q-
Mxcj
totalPage = totalRecords / everyPage + 1 ; ={E!8"
QJIItx4hE
return totalPage; fqk Dk
} M?~<w)L}
eMl]td rI
privatestaticboolean hasPrePage(int currentPage){ Jt>[]g$
return currentPage == 1 ? false : true; %6IlE.*,
} '0_j{ig
<.=#EV^i
privatestaticboolean hasNextPage(int currentPage, f{^M.G@
;?L!1wklA
int totalPage){ W93JY0Ls9|
return currentPage == totalPage || totalPage == Rw/JPC"
[cQ<dVaTX
0 ? false : true; Y!=
k
} 0ve`
+r-dr>&H@
v :+8U[x
} Dz8:;$/
R7B,Q(q2-
.mT#%ex
&8Jg9#
)zW%\s*'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 lLkmcHu
x!C8?K=|
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 P!FEh'.
t8DL9RW'
做法如下: {C/L5cZ]J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 s^g.42?u
$h 08Z
的信息,和一个结果集List: Xb=2/\}|f
java代码: ]|,q|c ,
~&DB!6*
9|N"@0<B
/*Created on 2005-6-13*/ -Wlp=#9
package com.adt.bo; {K45~ha9!m
qY$*#*Q
import java.util.List; ~_u*\]-
g|K6iY
import org.flyware.util.page.Page; WxVn&c\
wC(vr.,F
/** 4{;8:ax&w
* @author Joa %@lV-(5q
*/ SZ5O89
publicclass Result { _{LN{iqDv
9;0V
/y
private Page page; }W:*aU
N5 SLF4R1
private List content; hWD !
eyeNrk*2o
/** 8K\'Z
* The default constructor jWH{;V&ZV
*/ Em e'Gk
public Result(){ |SGgy|/a#
super(); .FIt.XPzv
} DtzA$|Q}
tcBC!_vF
/** B{7Kzwh;
* The constructor using fields <y@,3DD3A9
* 9=t#5J#O
* @param page )Y3EQxXa
* @param content $[Tt#CJw
*/ Ts|--,
public Result(Page page, List content){ TZ?Os4+
this.page = page; ;mDM5.iF
this.content = content; p"Ot5!F>
} C=fsJ=a5;
3/X-Cr+d
/** )!tCC-Cr
* @return Returns the content. e8$l0gzaD
*/ =%!e(N'p
publicList getContent(){ CY34X2F
return content; `AWy!}8
} 6}ce1|mkg/
(2UW_l
/** ?2{bKIV_
* @return Returns the page. Aj[?aL
*/ ]b 3/Es+
public Page getPage(){ ac9qj
return page; led))qd@V-
} Y 4d3n
&e5(Djz8t
/** Y RPm^kW
* @param content ).LTts7c
* The content to set. MR`:5e
*/ {9L 5Q
public void setContent(List content){ MhNFW'_
this.content = content; pe9@N9_5
} U#bl=%bF
#? dUv#
/** -
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* @param page ~4Pc_%&i
* The page to set. 7|YN:7iA
*/ n|Pr/ddL
publicvoid setPage(Page page){ wJgX/W
this.page = page; 9M_(He
-
} +iy7e6P
} Ir5WN_EaS
d6`OXTD
Wqra8u#
<\" .L
c"7j3/p
2. 编写业务逻辑接口,并实现它(UserManager, M`vyTuO3SO
ZQ3_y $
UserManagerImpl) XF|WCZUnY%
java代码: q@n^ZzTx
6 "U8V?E
T$KF<
=
/*Created on 2005-7-15*/ MxOD8TDF4
package com.adt.service; ][d,l\gu+s
,LZX@'5
import net.sf.hibernate.HibernateException; ?7jg(`Yh
/4$4h;_8
import org.flyware.util.page.Page; 8!mc@$Z
y,=du
import com.adt.bo.Result; aE|OTm+@9;
B&Y_2)v
/** iWE)<h
* @author Joa y{d^?(-
*/ Z{R[Wx
publicinterface UserManager { mM/i^zT
Lq (ZcEKo
public Result listUser(Page page)throws {_#y z\j
Q7gY3flg
HibernateException; LO:fJ{ -
TZRcd~ 5$
} vyI%3+N@
npp[@*~
1mH%H*#
(*\jbK
%."@Q$lA
java代码: o.-C|IXG
U__(;
/1;
7v7G[n
/*Created on 2005-7-15*/ pS[KBQ"F
package com.adt.service.impl; Ucdj4[/,h
%XTcP2pRJ
import java.util.List; <#+44>h
Pw0Ci
import net.sf.hibernate.HibernateException; 2F`cv1 M
SC &~s$P;
import org.flyware.util.page.Page; BxK^?b[E8
import org.flyware.util.page.PageUtil; ,`A?!.K$
B>y9fI
import com.adt.bo.Result; BV`- =wRC
import com.adt.dao.UserDAO; L,,*gK
import com.adt.exception.ObjectNotFoundException; ULH0'@BJ
import com.adt.service.UserManager; ,Gk}"w
AJ^#eY5
/** *Vw\'%p*
* @author Joa 4Kwh?8.
*/ qU6nJi+-I
publicclass UserManagerImpl implements UserManager { q.4A(,
3jH \yXj
private UserDAO userDAO; SJt<+kg
7Q w|!
/** 6 15s5ZA
* @param userDAO The userDAO to set. '_k+WH&
*/ C[!MS5
publicvoid setUserDAO(UserDAO userDAO){ 3bZIYF2@
this.userDAO = userDAO; [+m?G4[
} jw}}^3.
7!y5
SX8C
/* (non-Javadoc) SUKxkc(
* @see com.adt.service.UserManager#listUser @+F4YJmB?l
0$+fkDf
(org.flyware.util.page.Page) obrl#(\P
*/ :j')E`#
public Result listUser(Page page)throws OA/WtQ5
`LAR@a5i
HibernateException, ObjectNotFoundException { r;L>.wl*I
int totalRecords = userDAO.getUserCount(); uEyH2QO
if(totalRecords == 0) G0u LmW70
throw new ObjectNotFoundException 6
5y+Z
yme^b
;a
("userNotExist"); =[\s8XH,
page = PageUtil.createPage(page, totalRecords); ~_s?k3cd
List users = userDAO.getUserByPage(page); 53-v|'9'
returnnew Result(page, users); b^D$jY
} "s!7dKXI"
x8\A<(G_M=
} XU/QA
[K
;S0Kh"A
^Q*atU
SS`qJZ|w
PP:(EN1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ?(*t@
{k
+xc'1id@[
询,接下来编写UserDAO的代码: K=!Bh*
3. UserDAO 和 UserDAOImpl: pdJ/&ufh
java代码: [,2|Flf
e
2I*;A5$N1
D]c`B
/*Created on 2005-7-15*/ N2.AKH
package com.adt.dao; Og=*R6i
L?5Ck<!xG
import java.util.List; n,B,"\fw
*@d&5
import org.flyware.util.page.Page; |t; ~:A
>#,G}xf
import net.sf.hibernate.HibernateException; c@v{`d
0b4R
/** 'v]u#/7a
* @author Joa \:'%9 x
*/ bdGIF'p%
publicinterface UserDAO extends BaseDAO { A^q[N
3O7!`Nm@
publicList getUserByName(String name)throws wywQ<n
t3dlS`O
HibernateException; tv!_e$CR
uYE`"/h,1e
publicint getUserCount()throws HibernateException; 6252N]*
TDd{.8qf
publicList getUserByPage(Page page)throws Duc#$YfGm
4lBU#V7
HibernateException; F <hJp,q9
n u'M
39{
} X/N0LU(q
r#xg#u oj
|j 6OM{@
>@"Oe
M`ip~7"
java代码: ezPz<iZ\N
It{ ;SKeo
=zyC-;r!
/*Created on 2005-7-15*/ d6W SL;$
package com.adt.dao.impl; 1UKg=A-q
_6wFba@>/n
import java.util.List; `X3^fg
q7"7U=W0
import org.flyware.util.page.Page; |Pg@M
.nyfYa+
import net.sf.hibernate.HibernateException; Br`IW
import net.sf.hibernate.Query; .|/~op4;
9'r:~O
import com.adt.dao.UserDAO; zA[0mkC?$
6oBfB8]:d
/** 23h%
< ,
* @author Joa =9j8cC5y
*/ Ek6MYc8<b~
public class UserDAOImpl extends BaseDAOHibernateImpl 5< ja3
EOm:!D\
implements UserDAO { ` \+@Fwfx
lg(bDKm
/* (non-Javadoc) !H ~<
* @see com.adt.dao.UserDAO#getUserByName a<@N-E xr
G_SG
(java.lang.String) '7oA< R
*/ %?m$`9yU
publicList getUserByName(String name)throws ca>Z7qT!
#
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HibernateException { 6,9o>zT%H
String querySentence = "FROM user in class KG=h&
&-mX ,
com.adt.po.User WHERE user.name=:name"; . Z%{'CC
Query query = getSession().createQuery +-G<c6 |
AhNq/?Q Q~
(querySentence); F}=aBV|-
query.setParameter("name", name); "70WUx(\t
return query.list(); #H0dZ.$b0
}
K#U<ib-v
1n@8Kv
/* (non-Javadoc) ,%)6jYHR w
* @see com.adt.dao.UserDAO#getUserCount() rs~wv('
*/ o";Z$tAJkC
publicint getUserCount()throws HibernateException { qv@$ZLR
int count = 0; EbdfV-E
String querySentence = "SELECT count(*) FROM p1|f<SF')
tuhA
9}E
user in class com.adt.po.User"; AU$Uxwz4
Query query = getSession().createQuery V#`fs|e;y
HTyLJe
(querySentence); 8:/e
GM
count = ((Integer)query.iterate().next IqD_GL)Ms
QI3Nc8t_2
()).intValue(); uxzze~_+C
return count; fF V!)Zj
} :Cp'm'omb
/, ! B2
/* (non-Javadoc) Bn(W"=1
* @see com.adt.dao.UserDAO#getUserByPage ]~E0gsq
.;*s`t
(org.flyware.util.page.Page) dtcIC0:[
*/ Q
!(pE&
publicList getUserByPage(Page page)throws Y2?.}Z O
>J>b>SU=-
HibernateException { 1hziXC0WY
String querySentence = "FROM user in class XGkkB
a!u
rew#
com.adt.po.User"; }sOwp}FV8X
Query query = getSession().createQuery [NTtz
<i@
(bh95X
(querySentence); ,qYJioWX
query.setFirstResult(page.getBeginIndex()) ](^(=%
.setMaxResults(page.getEveryPage()); [/BE8]M~
return query.list(); HVC>9_:]
} ME=/|.}D<
h@LHRMO
} hjQ~uqbg
W[^qa5W<FB
Qx'`PNU9\
;ji pe3LU
37RLE1Yf
至此,一个完整的分页程序完成。前台的只需要调用 %3$*K\Ai
s$a09x
userManager.listUser(page)即可得到一个Page对象和结果集对象 7ek&[SJ>,/
g{P%s'%*
的综合体,而传入的参数page对象则可以由前台传入,如果用 FSRj4e1y1
PtTH PAKj
webwork,甚至可以直接在配置文件中指定。 VV9_`myN7
A+UU~?3y
下面给出一个webwork调用示例: -c}, :G"
java代码: <fs2fTUeqF
"5,
kn/Ao}J74z
/*Created on 2005-6-17*/ o#hjvg
package com.adt.action.user; bN3#{l-`
\~5C7^_
import java.util.List; |eWjYGwJa
E.U_W
import org.apache.commons.logging.Log; <3j"&i]Tm*
import org.apache.commons.logging.LogFactory; hnznp1[#@
import org.flyware.util.page.Page; ]7Z{ 8)T
o,P.&m{?
import com.adt.bo.Result; STJJU]H
import com.adt.service.UserService; A?@@*$&
import com.opensymphony.xwork.Action; Glpe/At
-<_Ww\%8M
/** 8dlw-Q'S
* @author Joa 7YAIA%8
*/ /P
2[:[w
publicclass ListUser implementsAction{ 1DA1N<'
M5trNSL&u
privatestaticfinal Log logger = LogFactory.getLog G!XIc>F*
>pr=|$zk=
(ListUser.class); Kn?lHH*w7
]K*8O<
private UserService userService; g38&P3/
ys#i@
private Page page; gp-T"l
"rAY.E]
privateList users; NzW`B^p
oQL59XOT4
/* x[Wwq=~
* (non-Javadoc) 1lpwZ"
* Ia'ZV7'
* @see com.opensymphony.xwork.Action#execute() @p|$/Z%R,
*/ 8#&q$kE
publicString execute()throwsException{ c c
Result result = userService.listUser(page); rP(eva
page = result.getPage(); :>81BuMvg
users = result.getContent(); |G/7_+J6
return SUCCESS; "p3_y`h6+
}
3!
~K^Z]
u(!&:A9JFd
/** `.2hjO
* @return Returns the page. k;5P om
*/ Cbs5dn(Y
public Page getPage(){ =@)d5^<5F
return page; S:61vD
} -<#!DjV6(
LZ~"VV^
/** qSx(X!YS
* @return Returns the users. 1h7+@#<:a
*/ Ac|5. ?|N
publicList getUsers(){ auWXgkwZs/
return users; rbZ[!LA
} X#w%>al
,pBh`av
/** tMj1~
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* @param page Q# ?wXX47
* The page to set. [ REf>_R
*/ i5F:r|
publicvoid setPage(Page page){ ^S#t|rN
this.page = page; u
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} `)4a[thp
.C]cK%OO
N
/** EC6k{y}bA
* @param users 5HS~op2n/
* The users to set. k8]O65t|
*/ ,L OQDIyn
publicvoid setUsers(List users){ Vc3mp;6"
this.users = users; kVS?RHR
} F&;
VzlDHpG
/** 6*@yE
* @param userService W0cgI9=9
* The userService to set. fMf&?`V
*/ nF)uTk
publicvoid setUserService(UserService userService){ ?nKF6f
this.userService = userService; iwY'4Z
e
} #:ns64|
} !~-6wN"k
jQj,q{eA
'b"TH^\
<JI&
{1
m|svQ-/j
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 4-v6=gz.
{fSfq&o
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ?PPZp6A3L=
tu%[p 4
么只需要: g\M5:Qm
java代码: X21dX`eMN
B>TSdn={>
uL?vG6% ^1
<?xml version="1.0"?> +'03>!V
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork t"s5\;IJ
R21~Q:b!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q9}m!*8e
PK rek
1.0.dtd"> .\5$MIF
M2T| "Q"=
<xwork> %c6E-4b
d$;/T('
<package name="user" extends="webwork- yFpySvj}
P -Fg^tl
interceptors"> SQ#7PKH
=ak7ldA=2
<!-- The default interceptor stack name oO=o|w|T
!Ua&0s%
--> 3x5!a5$Y
<default-interceptor-ref ^b53}f8H
y@apJ;_R-
name="myDefaultWebStack"/> d(L{!mm
VO`"<
<action name="listUser" fA8ozL T
A0#Y, 1
class="com.adt.action.user.ListUser"> J gi
Iq
<param \{PNw F?
3ps,uozj
name="page.everyPage">10</param> A4_>LO_qL
<result k:P$LzIB
8wF#e\Va0
name="success">/user/user_list.jsp</result> _bI+QC#
</action> 2a[9h#
:t2B^})\
</package> 3Xdn62[&
.fJ*c
</xwork> `-D$Fsl
"T*I|
}[,3yfiX
/2h][zrZ[.
2z-$zB<vyw
t:9
ZCu ay
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 @)z*BmP
cV]y=q6
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 pF='jj51
[.U^Wrd
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !`C%Fkq
^Fp=y,D
BkT-m'I?
*8206[y
l"L+e! B~
我写的一个用于分页的类,用了泛型了,hoho 5&qY3@I7l
r|bPR!0
java代码: qvTKfIl{
bm6hZA|
]Wy.R6
package com.intokr.util; qvTJ>FILT
`]hCUaV
import java.util.List; lEa W7j
R.UumBM
/** \^m.dIPdO
* 用于分页的类<br> ?'f^X$aS
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Gt5$6>A
* 5m3'Gt4
* @version 0.01 P#F_>GB
* @author cheng \6 LcV ik
*/ =g[H]-Ee
public class Paginator<E> { um}N%5GAa
privateint count = 0; // 总记录数 kDg{>mf
privateint p = 1; // 页编号 ^#7viZ*
privateint num = 20; // 每页的记录数 b.,$# D{p
privateList<E> results = null; // 结果 'ucGt
%Il ;B~t
/** J5-rp|
* 结果总数 }JH`'&3
*/
Y 0]Kl^\A
publicint getCount(){ hOl=W |)v
return count; .&L^J&V
} W'd/dKUx
6s&qZ+v-
publicvoid setCount(int count){ F[(6*/ 46x
this.count = count; LEA;dSf
} H}(=?}+
KKV)DExv?
/** 2!{N[*)
* 本结果所在的页码,从1开始 tw]/,>\G
* :(+]b
* @return Returns the pageNo. 3^'#ny?l
*/ |
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publicint getP(){ Io09W ^
return p; F"Uh/EO<
} tb:
`)LIVi"(D
/** 7<fL[2-
* if(p<=0) p=1 exsQmbj* %
* #fO*ROe
* @param p >QA/Mi~R
*/ BQE{
publicvoid setP(int p){ S ]vW&r3`
if(p <= 0) Jm%mm SYK
p = 1; )K8P+zn~
this.p = p; dG"K/|
} n#)PvV~
/cM 5
/** jGJ.Pvc>i
* 每页记录数量 B<(Pd
*/
dD :
publicint getNum(){ uAc@ Z-
return num; =rtS#u
Y
} s bs[=LW4
-*rHB&e
/** 7 kEx48
* if(num<1) num=1 C{8i7D
*/ 2%`^(\y
publicvoid setNum(int num){ {qJHL;mP:8
if(num < 1) U LV)0SB
num = 1; $+A%ODv
this.num = num; qPL^zM+
} E"G:K`Q
(zjz]@qJ
/** <j{0!J@:
* 获得总页数 +Gk!
t]dy
*/ e 4 p*51ra
publicint getPageNum(){ @^'G&%j
return(count - 1) / num + 1; )>-77\
} _)OA$
tx2Vyu
/** S`ax*`
* 获得本页的开始编号,为 (p-1)*num+1 unC t4uX^
*/ -iY9GN89c
publicint getStart(){ /'R UA
return(p - 1) * num + 1; x>U1t!'
} JRHf.?
}f<fgY
/** 9@$tiDV
* @return Returns the results. %bCcsdK
*/ 73&]En
publicList<E> getResults(){ *37LN
return results; ,[Dh2fPM,
} d9`3EP)n
H.jLGe>
public void setResults(List<E> results){ kHt!S9r
this.results = results;
ZAI1p+
} *,O
:>Z5I
Sf+(1_^`t
public String toString(){ hEyX~f
StringBuilder buff = new StringBuilder `ENlV9
K*([9VZ
(); &(5^vw<0
buff.append("{"); K[iY{
buff.append("count:").append(count); \SYPu,ZT
buff.append(",p:").append(p); 5QqJI#4~
buff.append(",nump:").append(num); r~S!<9f
buff.append(",results:").append x:f|3"\s
L #t-KLJ
(results); sDzD
8as
buff.append("}"); M!xm1-,[
return buff.toString(); xHM&csL
} BxSk%$J
'0'"k2"vC
} "@c';".|
v`z=OHc
b9W<1eqF