Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *FZav2]-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 d,Oagx
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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 g7*Uuh#
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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 ~1twGG_;
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分页支持类: o|c6=77043
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java代码: M"/Jn[
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package com.javaeye.common.util; WWZ<[[ >
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import java.util.List; =s]2?m
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publicclass PaginationSupport { ~9yKMUf
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publicfinalstaticint PAGESIZE = 30; a7F_{Mm
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privateint pageSize = PAGESIZE; I}0? d
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privateList items; _5~|z$GW
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privateint totalCount; ZeU){CB
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privateint[] indexes = newint[0]; pUF JQ*
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privateint startIndex = 0; H@$K/
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public PaginationSupport(List items, int / Wjc\n$'
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totalCount){ &B[*L+-E
setPageSize(PAGESIZE); HQ"
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setTotalCount(totalCount); }zsIp,
setItems(items); .
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setStartIndex(0); .!Z5A9^
} FA)ot)]
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public PaginationSupport(List items, int h9<PP2.(
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totalCount, int startIndex){ -Fn/=
setPageSize(PAGESIZE); '/9j"mIA9$
setTotalCount(totalCount); U:n~S
setItems(items); ?QJx!'Y,p
setStartIndex(startIndex); gT$WG$^i
} FK~wr;[
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public PaginationSupport(List items, int Sk!' 2y*@&
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totalCount, int pageSize, int startIndex){ )xa)$u
setPageSize(pageSize); $hcv}<$/
setTotalCount(totalCount); @<pd@Mpf]
setItems(items); R8u8jG(4
setStartIndex(startIndex);
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} ]?D$n
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publicList getItems(){ _BerHoQd
return items; V*Fy@
} %%?}db1n
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publicvoid setItems(List items){ |UWIV
this.items = items; eZ]r"_?
} ]1d)jWG
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publicint getPageSize(){ % R25, V
return pageSize; d$bO.t5CLh
} P![ZO6`:W'
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publicvoid setPageSize(int pageSize){ Tc||96%2^
this.pageSize = pageSize; V61oK
} .[]S!@+%
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publicint getTotalCount(){ ArAe=m!u
return totalCount; JvW7h(u7g
} 4_j_!QH87
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publicvoid setTotalCount(int totalCount){ V'W*'wo
if(totalCount > 0){ E=,5%>C0#%
this.totalCount = totalCount; .`+~mQ
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int count = totalCount / "i/GzD7 `n
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pageSize; $#s5y~z
if(totalCount % pageSize > 0) sGtxqnX:J
count++; BV>9U5
indexes = newint[count]; /]Y#*r8jRi
for(int i = 0; i < count; i++){ v@[3R7|4
indexes = pageSize * i*mU<:t
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} hOZTD0
}else{ R--s
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this.totalCount = 0; '*rS,y
} K g#Bg##
} Aqf91
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publicint[] getIndexes(){ ineSo8| @
return indexes; 27c0wzq
} t!/~_}eD J
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publicvoid setIndexes(int[] indexes){ SUMfebW5
this.indexes = indexes; {[Ri:^nHgL
} T?!SEblP]
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publicint getStartIndex(){ >\pF5a`
return startIndex; %u&Vt"6m=
} Qfy_@w]
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publicvoid setStartIndex(int startIndex){ 86-Rm
if(totalCount <= 0) r5hkxk'
this.startIndex = 0; DeF`#a0E
elseif(startIndex >= totalCount) I
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this.startIndex = indexes T|S-?X,
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[indexes.length - 1]; |z_Dw$-xm
elseif(startIndex < 0) 5 cQ]vb
this.startIndex = 0; v}t{*P
else{ F3!@|/<w
this.startIndex = indexes #BBDI
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[startIndex / pageSize]; a-,*iK{_u
} -YQS\@?
} !=.y[Db=
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publicint getNextIndex(){ !]uB4
int nextIndex = getStartIndex() + CStNCBZ|\
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pageSize; z-We>KX
if(nextIndex >= totalCount) "OI$PLK
return getStartIndex(); cW0\f5[/
else |iBf6smF
return nextIndex; CT|0KB&
} [O_5`X9|
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publicint getPreviousIndex(){ ATc!c +
int previousIndex = getStartIndex() - uQ[,^Ee&/
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pageSize; 2@Nd02v|
if(previousIndex < 0) ~$4(|Fq/
return0; UYZC% $5x
else UIf#Gy|l
return previousIndex; (NR( )2
} }E(w@&
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} %{r3"Q=;W
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抽象业务类 yxpv;v:)=
java代码: X!z-J>
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/** #M w70@6
* Created on 2005-7-12 r]\[G6mE%
*/ ) aMiT
package com.javaeye.common.business; Fng
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import java.io.Serializable; N@<-R<s^
import java.util.List; ;2g.X(Ra
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import org.hibernate.Criteria; >ZPu$=[W
import org.hibernate.HibernateException; v:74iB$i/C
import org.hibernate.Session; RLQ*&[A}
import org.hibernate.criterion.DetachedCriteria; OMjPC_
import org.hibernate.criterion.Projections; hC<E4+5.,
import mpwh=
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org.springframework.orm.hibernate3.HibernateCallback; z@19gD#8
import h2mHbe43
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org.springframework.orm.hibernate3.support.HibernateDaoS ShV_8F z
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upport; CfrO1i F
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import com.javaeye.common.util.PaginationSupport; h0~<(3zC
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public abstract class AbstractManager extends S\I+UeFkf
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HibernateDaoSupport { => 'j_|
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privateboolean cacheQueries = false; =<9Mv+Ry8
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privateString queryCacheRegion; NqKeQezX
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publicvoid setCacheQueries(boolean &*O'qOO<2
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cacheQueries){ oM@%2M_O(
this.cacheQueries = cacheQueries; u"hr4+/
} pQ7elv]
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publicvoid setQueryCacheRegion(String OC,yL Q
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queryCacheRegion){ e"sv_$*
this.queryCacheRegion = 6A>bm{`c:
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queryCacheRegion; uInI{>
} (?,jnnub
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publicvoid save(finalObject entity){ _f>)G3p
getHibernateTemplate().save(entity); T&S=/cRBK}
} L)7{_s
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publicvoid persist(finalObject entity){ gxI/MD~!>
getHibernateTemplate().save(entity); c(8>oeKyD
} t Jtp1$h
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publicvoid update(finalObject entity){ Fpn'0&~-fi
getHibernateTemplate().update(entity); ?AxB0d9z
} 6yYd~|T.Fl
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publicvoid delete(finalObject entity){ s`,g4ce`
getHibernateTemplate().delete(entity); {s6#h #U
} rW O#h{
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publicObject load(finalClass entity, 86qQ"=v
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finalSerializable id){ Ik5-ooZ&{
return getHibernateTemplate().load a.O"I3{?h
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(entity, id); Eoo[H2=^H
} q:jv9eL.O
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publicObject get(finalClass entity, Ei<+{P(t0
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finalSerializable id){ qnd] UUA^
return getHibernateTemplate().get _Y6Ezh.
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(entity, id); %M^Q{`
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} NX;{L#lQ
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publicList findAll(finalClass entity){ oz3!%'
return getHibernateTemplate().find("from f::^zAV
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} trLxg H_Y
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publicList findByNamedQuery(finalString I%j]p Y4
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namedQuery){ -biw{
return getHibernateTemplate =:xJZy$
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().findByNamedQuery(namedQuery); wt_ae|hv
} ">fRM=fl
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publicList findByNamedQuery(finalString query, @ K2N cb7
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finalObject parameter){ I;$tBgOWq
return getHibernateTemplate DEfhR?v
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().findByNamedQuery(query, parameter); n|QA\,=
} QqeF
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publicList findByNamedQuery(finalString query, EW)r/Av:,
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finalObject[] parameters){ 4l/~::y
return getHibernateTemplate <X97W\
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().findByNamedQuery(query, parameters); 5':j=KQE_
} <P Vmr2Jp"
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publicList find(finalString query){ lKRp9isn^
return getHibernateTemplate().find >Mm.MNU
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(query); %uP/v\l
} TUp%Cx
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publicList find(finalString query, finalObject &(x>J:b
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parameter){ p1z^i(
return getHibernateTemplate().find ,~K4+
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(query, parameter); !) d
} cZt5;"xgr]
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public PaginationSupport findPageByCriteria 4tapQgj24
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(final DetachedCriteria detachedCriteria){ ]zvOM^l~
return findPageByCriteria T?-K}PUcQ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); L#_QrR6Sny
} <%`z:G3
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public PaginationSupport findPageByCriteria b0/[+OY
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(final DetachedCriteria detachedCriteria, finalint g87M"kQKA
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startIndex){ z-S8s2.Fd
return findPageByCriteria JQ\o[t
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(detachedCriteria, PaginationSupport.PAGESIZE, @c,=c+-
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startIndex); 5pE@Ww
} .Ag)/Xm(?
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public PaginationSupport findPageByCriteria @d[)i,d:G
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(final DetachedCriteria detachedCriteria, finalint <,nd]a
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pageSize, V}G;oz&>)
finalint startIndex){ .ityudT<
return(PaginationSupport) &gvX<X4e
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getHibernateTemplate().execute(new HibernateCallback(){ =Ajw(I[56
publicObject doInHibernate n]wZ7z
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(Session session)throws HibernateException { 79M`?xm
Criteria criteria = )|S!k\^A
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detachedCriteria.getExecutableCriteria(session); 4+0:(=>[%
int totalCount = B|BJkY'
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((Integer) criteria.setProjection(Projections.rowCount G9>
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()).uniqueResult()).intValue(); O@KAh5EB
criteria.setProjection A Rjox`
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(null); sVIw'W
List items = \OF"hPq
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criteria.setFirstResult(startIndex).setMaxResults 9'\*Ip^
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(pageSize).list(); I [v~nY~l`
PaginationSupport ps = l8!n!sC[,
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new PaginationSupport(items, totalCount, pageSize, zeHs5P8}r
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startIndex); *U4eL-
return ps; gMZ
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} -M?s<R[&
}, true); :U#4H;kk~j
} 0o&7l%Y/
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ ?-PW$p
return(List) getHibernateTemplate |Ns[{/
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().execute(new HibernateCallback(){ I78huYAYA
publicObject doInHibernate 0SWec7G
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(Session session)throws HibernateException { PF/eQZ*4
Criteria criteria = 25`6V>\
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detachedCriteria.getExecutableCriteria(session); ~G`(=\_0
return criteria.list(); 5ayH5=(t
} Zo36jSrCL
}, true); ^Zw1X6C5~
} Y[ toN9,
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public int getCountByCriteria(final 3+$~l5LY
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DetachedCriteria detachedCriteria){ ZZ{:f+=?$
Integer count = (Integer) }Z}4_/E
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getHibernateTemplate().execute(new HibernateCallback(){ aUX.4#|%
publicObject doInHibernate FOd)zU*L2
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(Session session)throws HibernateException { &p#.m"Oon
Criteria criteria = N[AX]gOJ
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detachedCriteria.getExecutableCriteria(session); ibskce{H
return 8;]U:tv
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criteria.setProjection(Projections.rowCount 3)+}2
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()).uniqueResult(); F2RU7o'f.
} :Sd
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}, true); ?Dk&5d^d
return count.intValue(); u>o2lvy8
} Mk@%Wuxg2
} E"$AOM?(*i
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用户在web层构造查询条件detachedCriteria,和可选的 q}mQm'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 A~Ov(
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PaginationSupport的实例ps。 "]C$"JR
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ps.getItems()得到已分页好的结果集 1zUo.Tg0
ps.getIndexes()得到分页索引的数组 oO8V0VE\
ps.getTotalCount()得到总结果数 *^q%b/ f
ps.getStartIndex()当前分页索引 c>%+y+b{
ps.getNextIndex()下一页索引 V.*0k~
ps.getPreviousIndex()上一页索引 xr*hmp1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Gn_rf"
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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 xi2!__
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一下代码重构了。 i?&g;_n^
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我把原本我的做法也提供出来供大家讨论吧: +84JvOkWi
Hki
首先,为了实现分页查询,我封装了一个Page类: & A%*sD6
java代码: -~-BQ!!(
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/*Created on 2005-4-14*/ QFm~wv8:
package org.flyware.util.page; q;p:)Q"
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/** b]Xc5Dp{
* @author Joa ,dM}B-
* 7]w]i5
*/ -5~&A6+ILn
publicclass Page { }x^q?;7xW
~al4`:rRx1
/** imply if the page has previous page */ Rh:edQ#
privateboolean hasPrePage; <V-D
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/** imply if the page has next page */ V~>
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privateboolean hasNextPage; WML%yO\.;
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/** the number of every page */ V]V~q ]
privateint everyPage; a.r+>44M
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/** the total page number */ ep-~;?
privateint totalPage; I'M,p<B
gxS*rzCG
/** the number of current page */ 8R;)WlLu=
privateint currentPage; :qbbo~U
vnT'.cBB:^
/** the begin index of the records by the current ',o ,o%n
*-gd k9
query */ -Q6njt&
privateint beginIndex; tw/~z2G
G{,X_MZ%
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/** The default constructor */ 9 -\.|5;:
public Page(){ [f9U9.fR
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} aB6F<"L,
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/** construct the page by everyPage e^?0uVxS1
* @param everyPage pDlU*&
* */ tCFXb6Cz
public Page(int everyPage){ dy^Zlu`
f
this.everyPage = everyPage; p<w2e
} Q{ibH=^
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/** The whole constructor */ %Y7\0q~Z
public Page(boolean hasPrePage, boolean hasNextPage, Z Sj[GI
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int everyPage, int totalPage, =BN_Kvza^6
int currentPage, int beginIndex){ UE2!,Z,
this.hasPrePage = hasPrePage; ^gY^I`"e6
this.hasNextPage = hasNextPage; \J>a*
this.everyPage = everyPage; dX4"o?KD>
this.totalPage = totalPage; 2E
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this.currentPage = currentPage; 8Z{e/wnVF
this.beginIndex = beginIndex; uTgvMkO
} MCBZq\c
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/** "enGWIH
* @return KiXRBFo
* Returns the beginIndex. aNX M~;5~
*/ EZ6\pyNB0#
publicint getBeginIndex(){ To_Y
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return beginIndex; HzcI2
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} gVM&wo |
t u)kWDk
/**
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* @param beginIndex 8reis1]2S
* The beginIndex to set. V&i/3g
*/ z+RA
publicvoid setBeginIndex(int beginIndex){ R4 8w\?L
this.beginIndex = beginIndex; F|,_k%QP
} v1s.j2T
n]?KDID;
/** A2fc_A/a
* @return v{/z`J!JR
* Returns the currentPage. A4lW8&rHI
*/ 8.9Z0
publicint getCurrentPage(){ tVB9kxtE
return currentPage; f-lM[\ma_
} IYIlab\TZ
1{TmK9U
/** f,Z*o
* @param currentPage qhFWQ1W
* The currentPage to set. mBQA~@}
*/ T$p!IRPt
publicvoid setCurrentPage(int currentPage){ l :e&w(1H
this.currentPage = currentPage; 7+!4pf
} *]
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N:"S/G>r ;
/** <OQn|zU\
* @return S}@J4}*u["
* Returns the everyPage. kx6AMx!nX
*/ ZCP
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publicint getEveryPage(){ :Pa^/i
return everyPage; }XJA#@
} M0+xl+c+
`x{*P.]N!<
/** |ia#Elavo
* @param everyPage ]LcCom:]
* The everyPage to set. wZ&l6J4L
*/ WOw( -
publicvoid setEveryPage(int everyPage){ )Z.v fc
this.everyPage = everyPage; #qx$ p
} 2P`Z>_
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/** DZ-2Z@{PX
* @return C;mcb$@
* Returns the hasNextPage. aYJTSgW
*/ t)!(s,;T
publicboolean getHasNextPage(){ ,;&j*qFi
return hasNextPage; %T~3xQ
} ~AqFLv/%
[&Yrnkgr
/** IE^xk@
* @param hasNextPage 'AU:[eyUV
* The hasNextPage to set. %5?Zjp+9
*/ "s$$M\)T
publicvoid setHasNextPage(boolean hasNextPage){ thT2U8%T
this.hasNextPage = hasNextPage; 8h,>f#)0c
} 8-s7^*!
GkOZ=ej
/** &xAwk-{W
* @return T[M:%vjYF
* Returns the hasPrePage. VLdQXNg9W"
*/ y.iA]Ikz
publicboolean getHasPrePage(){ n<GTc{>Z
return hasPrePage;
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} QfdATK P
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/** (_9 u<
* @param hasPrePage
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* The hasPrePage to set. ^k*h
*/ {5GXN! f
publicvoid setHasPrePage(boolean hasPrePage){ PVC Fh$pnw
this.hasPrePage = hasPrePage; W@bZ~Q9
} HX)oN8
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/** 4r+@7hnK
* @return Returns the totalPage. %1oh+'ES F
* G!G]*p5
*/ lG1\41ZxB
publicint getTotalPage(){ y-.<iq
return totalPage; 5YZh e4R
} MWl2;qi
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/** m@,u&9K
* @param totalPage V_x8
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* The totalPage to set. SsY:gp_
*/ eBZ94rA]
publicvoid setTotalPage(int totalPage){ 9I|D"zXn
this.totalPage = totalPage; pO_$ 8=G+
} ;h7W(NO~z
hI$IBf>
} -eQ>3x&3r
f>!H<4
]
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Pg''>6w>
hy]8t1894
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 at
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个PageUtil,负责对Page对象进行构造: ;%ng])w=;
java代码: 59@PY! c>
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/*Created on 2005-4-14*/ 1(diG&
package org.flyware.util.page; Q?g#?z&Pu\
+$;#bw)yH
import org.apache.commons.logging.Log; ]4X08Cm^
import org.apache.commons.logging.LogFactory; 5qL;@Y
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/** ~VKuRli|m
* @author Joa j=up7395
* ?!Wh ^su-
*/ fi
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publicclass PageUtil { .FdzEauVc
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privatestaticfinal Log logger = LogFactory.getLog JeXA*U#
yt4sg/]:
(PageUtil.class); 0^25uAD=
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/** ,Qh9}I7;C
* Use the origin page to create a new page .3
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* @param page HYwtGj~5
* @param totalRecords 4;|@eN
* @return @UK%l
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*/ N?{.}-Q
publicstatic Page createPage(Page page, int 03?7kAI
J?$`Tnx^
totalRecords){ 8=-/0y9,
return createPage(page.getEveryPage(), [W8"Mc|ve
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page.getCurrentPage(), totalRecords); qy( kb(J
} d1>L&3HKx
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/** (^~0%1
* the basic page utils not including exception kTfE*We9
}nK=~Wcu\
handler Maw$^Tz,
* @param everyPage aJzyEb
* @param currentPage GTocN1,Z~a
* @param totalRecords f5`q9w_c
* @return page ,GYK3+}Z
*/ [!S%nYs&8L
publicstatic Page createPage(int everyPage, int ($X2SIZh
}I"k=>Ycns
currentPage, int totalRecords){ V2B:
DIpr
everyPage = getEveryPage(everyPage); G@4n]c_
currentPage = getCurrentPage(currentPage); U:fGIEz{ZY
int beginIndex = getBeginIndex(everyPage, p;<aZ&@O
9TUB3x^
currentPage); ,ieew`
int totalPage = getTotalPage(everyPage, ai]KH7
cR6Rb[9 N
totalRecords); qir8RPW
boolean hasNextPage = hasNextPage(currentPage, VfT@;B6ALF
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totalPage); K9_@[}Ge
boolean hasPrePage = hasPrePage(currentPage); lhBu?q
3|
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returnnew Page(hasPrePage, hasNextPage, u|sdQ
everyPage, totalPage, R/\ qDY,@
currentPage, ;8Ts
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beginIndex); (r-8*)Qh8
} LJwy,-
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privatestaticint getEveryPage(int everyPage){ }Sh3AH/
return everyPage == 0 ? 10 : everyPage; bcUa'ZfN<
} ?hOvY)
M6lNdK
privatestaticint getCurrentPage(int currentPage){ @^t1SPp
return currentPage == 0 ? 1 : currentPage; bE%*ZB
} 1UN$eb7
J l
fIYf~
privatestaticint getBeginIndex(int everyPage, int *XkgwJq
Dq<!wtFG[
currentPage){ qpX`ZY^
return(currentPage - 1) * everyPage; jJK@i\bU_
} V5!mV_EoR@
.|/VD'xV"
privatestaticint getTotalPage(int everyPage, int [u;>b?[{
o(@^V!}V
totalRecords){ V?r(; x
int totalPage = 0; $|o[l.q2
S.*.nv
if(totalRecords % everyPage == 0) 4p&YhV7j)o
totalPage = totalRecords / everyPage; t]XF*fZH
else 8S@"6TG`
totalPage = totalRecords / everyPage + 1 ; )E}eK-Yu
la_FZ
return totalPage; X8 x:/]/0
} E.4 X,
K[[ 5H
privatestaticboolean hasPrePage(int currentPage){ wF)g@cw
return currentPage == 1 ? false : true; "q7pkxEuJ
} [W8?ww%qT
w^)_Fk3
privatestaticboolean hasNextPage(int currentPage, qFwAzW;"
{KqERS&
g
int totalPage){ Wo,fHY
return currentPage == totalPage || totalPage == nq*D91Q
}3S6TJ+
0 ? false : true; $c];&)7q
} 6G;t:[H G
]Vd1fkXO0
8M6Qn7{L
} N3&n"w _d
,H5o/qNU`{
%!V =noo
g*$yUt
jWGX:XB
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。 wQrD(Dv(yA
RO.bh#A$
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 !UX7R\qu|
FK,Jk04on
做法如下: wbbr8WiU
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ZWy,NN1
F=V_ACU
的信息,和一个结果集List: m8z414o
java代码: vf
h*`G$
M*<Bp
W-ol*S
/*Created on 2005-6-13*/ F5YHc$3^
package com.adt.bo; =f=,YcRn+
3NlG,e'T2
import java.util.List; '9Xw_1B
OYY_@'D
import org.flyware.util.page.Page; giu8EjzK
1fcyGZq
/** b)+;@wa~
* @author Joa W4rh7e4
*/ NqZR*/BOz
publicclass Result { oU)HxV
XO"BEj<x
private Page page; ziG]BZ
~MZ.988:<
private List content; rtk1 8U-
j(`V&S
/** k4BiH5\hA
* The default constructor V1\x.0Fs
*/ <dX7{="&
public Result(){ nCSXvd/
super(); R\>=}7
} .6y(ox|LL
x#TWZ;
/** m|k:wuzqK
* The constructor using fields : t6.J
* /rmm@
* @param page !_LRuqQ?"
* @param content D(^ |'1
*/ ~e R6[;
public Result(Page page, List content){ 5wGc"JHm
this.page = page; F(+dX4$
this.content = content; mc}r15:<
} YLe$Vv735
Mf.:y
/** .[hbiv#
* @return Returns the content. =U<6TP]{
*/ m/>z}d05h
publicList getContent(){ XCku[?Ix
return content; [iT#Pu5
} 6j=a
rw]*Nxgr
/** ]{E{ IW8
* @return Returns the page. 3&vUR(10
*/ xN]88L}Tn
public Page getPage(){ 1F58 2 l
return page; a>/jW-?
} 2=ZZR8v
T0Zv.
/** ]WP[hF
* @param content DeL7sU
* The content to set. E/N*n!sV
*/ WMXk-?v4
public void setContent(List content){ <-m?l6
this.content = content; uZ7~E._
} 0G"I}Jp{
]aVFWzey
/** d!]fou
* @param page V;t8v\
* The page to set. /?Fa<{
*/ b|z_1j6U
publicvoid setPage(Page page){ dr8`;$;G*
this.page = page; ILq"/S.
} +x"cWOg
} YJEL'k<l
;*_U)th
I%fz^:[#<
y:N>t+'5
^9PB+mz
2. 编写业务逻辑接口,并实现它(UserManager, *1fZcw'C.
Ib665H7w
UserManagerImpl) @I$;
java代码: tZn=[X~Vw@
yvz2eAXa
FtL{f=
/*Created on 2005-7-15*/ }I;5yk,o
package com.adt.service; ><Z`)}f
]$gBX=
import net.sf.hibernate.HibernateException; 4)=\5wJDg1
/\&Wk;u3
import org.flyware.util.page.Page; Q-LDFnOFwp
muqIh!nn
import com.adt.bo.Result; =7WE
]jL`*tI\S
/** 3d0Yq
* @author Joa (e$/@3*
*/ (1my9k5C
publicinterface UserManager { Q~p[jQ,4wZ
]C
me)&hX
public Result listUser(Page page)throws t6H9Q>*
A&~<qgBTp
HibernateException; E6NrBPm
>9v?p=
} Pxn;]!Z#
\x_fP;ma=_
G~\ SI.
LVj62&,-
$2j?Z.yEG
java代码: 47c` ) *Hc
^,.G<2Kx&
d=B
DR^/wA
/*Created on 2005-7-15*/ !z.C}n5F
package com.adt.service.impl; }4n?k'_s?
d\{#*{_A
import java.util.List; ^YLpZoo
}m6j6uAR6)
import net.sf.hibernate.HibernateException; =<M7t*!
_+\hDV>v
import org.flyware.util.page.Page; 5Se
S^kJC
import org.flyware.util.page.PageUtil; iVKX *kqc
~!w()v n
import com.adt.bo.Result; &E>zvRBQ
import com.adt.dao.UserDAO; 8I'Am"bc\
import com.adt.exception.ObjectNotFoundException; J0hY~B~X
import com.adt.service.UserManager; Q*+_%n1
/
\dL#PI3
/** .RNr^*AQ
* @author Joa *&vySyt
*/ A
S#D9o
publicclass UserManagerImpl implements UserManager { aTceGyWzl
+AT!IZrB2i
private UserDAO userDAO; %7$oig\wE
DNy1} 3wg
/** ?kvkdHEO_
* @param userDAO The userDAO to set. +I?T|Iin
*/ u$Za hN!
publicvoid setUserDAO(UserDAO userDAO){ D*oJz3[
this.userDAO = userDAO;
e8TJ =}\
} /_rg*y*
jR^>xp;
/* (non-Javadoc) I&e,R
* @see com.adt.service.UserManager#listUser >qSaF
8\~IwtSk
(org.flyware.util.page.Page) r"MKkSEM
*/ T&2aNkuG
public Result listUser(Page page)throws kOfu7Zj
hk O)q|1
HibernateException, ObjectNotFoundException { +C{ %pF
int totalRecords = userDAO.getUserCount(); [akyCb
if(totalRecords == 0) Us]Uy|j
throw new ObjectNotFoundException cXO_g!&2A
c !ybz{L
("userNotExist"); ZZa$/q"
page = PageUtil.createPage(page, totalRecords); z.9
#AN=&[
List users = userDAO.getUserByPage(page); AID}NQQj_
returnnew Result(page, users); ^%v<I"<Uq5
} ?`hk0q X3
~?pF'3q
} tVN#i
J!QzF)$4J
7]q$sQ
hwmpiyu
z90=,wd
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I499Rrw#E
*n)3y.s
询,接下来编写UserDAO的代码: G}tq'#]E{z
3. UserDAO 和 UserDAOImpl: ] Qp0|45=
java代码: G;+hc%3y
-L/5Nbup
MK]S205{
/*Created on 2005-7-15*/ }{^i*T5rl
package com.adt.dao; z/7H/~d
1R/=as,R
import java.util.List; -4JdKO
9Q".166
import org.flyware.util.page.Page; >sE5zj|V
wR;_x x
import net.sf.hibernate.HibernateException; ]FLuiC
W"mkNqH
/** %$
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* @author Joa Te"<.0~1
*/ >9f-zv(n
publicinterface UserDAO extends BaseDAO { c FjC
8VLr*83~8
publicList getUserByName(String name)throws a4
g~'^uC
0;Y_@UVj
HibernateException; LB1.N!q1
u OEFb
publicint getUserCount()throws HibernateException; ;APpgt4
46'EZ@#s
publicList getUserByPage(Page page)throws Ed|7E_v
%}G:R!4 d
HibernateException; Q1Z;vzQfg
%S22[;v{N
} cI3uH1;#
z(^p@&r)F
U~SK 'R
TA=Ij,z~
S:] w@$
java代码: nMcd(&`N
bw{%X
>RxZ-.,a
/*Created on 2005-7-15*/ T7YzO,b/
package com.adt.dao.impl; :yvUHx
5:f}bW*
import java.util.List; 6^zuRY;
Dyp'a
import org.flyware.util.page.Page; -aGv#!aIl
FXFQ@q*}v
import net.sf.hibernate.HibernateException; Dj>.)n
import net.sf.hibernate.Query; H BmjB=
AKM\1H3U
import com.adt.dao.UserDAO; `3r *Ae
p&bQ_ XOH
/** 4qjY,QJ
* @author Joa C+}uH:I'L
*/ J3Q.6e=7
public class UserDAOImpl extends BaseDAOHibernateImpl SSi}1
Dw{C_e
implements UserDAO { yPm)r2Ck
SDV} bN
/* (non-Javadoc) "P< drz<
* @see com.adt.dao.UserDAO#getUserByName _y`'T;~OY
C,-V>bx g
(java.lang.String) 1K,bmb xRt
*/ qO>BF/)a(
publicList getUserByName(String name)throws
w IT`OT6Q
qwA:o-q"
HibernateException { Zx5vIm
String querySentence = "FROM user in class hGF:D#jyT
lXm]1
*<
com.adt.po.User WHERE user.name=:name"; d OqwF
iO
Query query = getSession().createQuery G\TyXq_4
8Md*9E#J("
(querySentence); wmY6&^?uS
query.setParameter("name", name); 0_Etm83Wq6
return query.list(); dW!T.S
} 6ssZg@}nf{
=bf-+gZD
/* (non-Javadoc) *8"5mC;"
* @see com.adt.dao.UserDAO#getUserCount() Czb@:l%sc
*/ P 2;j>=W
publicint getUserCount()throws HibernateException { g;=jZ
int count = 0; ep[7#\}5
String querySentence = "SELECT count(*) FROM SL:o.g(>4
?{cF'RB.
user in class com.adt.po.User"; !e.@Xk.P6
Query query = getSession().createQuery j/wNPB/NM
Tb}`]Y`X
(querySentence); V# w$|B\
count = ((Integer)query.iterate().next o?^j1\^
s<z{ (a
()).intValue(); 4jis\W}%L3
return count; if:2sS9r
} @<},- u
ksm=<I"C
/* (non-Javadoc) EEn}Gw
* @see com.adt.dao.UserDAO#getUserByPage ~|Gtm[9Ru
e|AJxn]
(org.flyware.util.page.Page) jbC7U9t7
*/ CbS9fc&
publicList getUserByPage(Page page)throws |,t#Au}61
fVo)# Bj
HibernateException { }RDhI1x[mk
String querySentence = "FROM user in class 6P?
]t7<$L
com.adt.po.User"; 7Y@&&
Query query = getSession().createQuery athU
qN+ ngk,:
(querySentence); 33[2$FBf
query.setFirstResult(page.getBeginIndex()) ]_|qv1K6
.setMaxResults(page.getEveryPage()); hV'JTU]H
return query.list(); #12PO q
} yZ 6560(q
l4hC>q$T
} '!{zO"
1*
$C(}
E n{vCN
eNu`\
N}VKH5U|
至此,一个完整的分页程序完成。前台的只需要调用 3HFsR)
RH6qi{)i!
userManager.listUser(page)即可得到一个Page对象和结果集对象 98Pt&C? -B
|53Zg"!
的综合体,而传入的参数page对象则可以由前台传入,如果用 TS$ 2K
Q>JJI:uC4
webwork,甚至可以直接在配置文件中指定。 ph%/;?wY
fX#Em'Ab[
下面给出一个webwork调用示例: ?8b?{`@V
java代码: `dn|nI2
U`IDZ{g
hUB_[#8#
/*Created on 2005-6-17*/ =<iK3bPkU
package com.adt.action.user; ?o),F^ir
,V.X-`Y
import java.util.List; 5sFp+_``
%@kmuz??
import org.apache.commons.logging.Log; #s)6u?N
import org.apache.commons.logging.LogFactory; kVy%y"/
import org.flyware.util.page.Page; @aY 8VL7C0
& 2>W=h
import com.adt.bo.Result; t~Cul+
import com.adt.service.UserService; z[}[:H8
import com.opensymphony.xwork.Action; =+'4u
EF qWnz
/** @lDoMm,m'
* @author Joa j5G8IP_Wx
*/ `kVy1WiY
publicclass ListUser implementsAction{ C:0Ra^i ?L
DE^{8YX,
privatestaticfinal Log logger = LogFactory.getLog K.",=\53
HPg@yx"U
(ListUser.class); #l+U(zH:JG
,g6w2y7 ]
private UserService userService; /b@8#px
k^S=i_ U
private Page page; bh3}[O,L
A
u!
x9O8y
privateList users; +i4S^B/8i
#fRhG^QKp
/* "qIO,\3T
* (non-Javadoc) lBgf' b3$
* 9`$fU)K[Pl
* @see com.opensymphony.xwork.Action#execute() go@UE2qw
*/ /al(=zf
publicString execute()throwsException{ 1ePZs$
Result result = userService.listUser(page); ]xCJ3.9
page = result.getPage(); 25::z9i
users = result.getContent(); tl
(2=\
return SUCCESS; '_@Y
} 5 nkx8JJ
>hJ$~4?
/** |K,9EM3
* @return Returns the page. &Op, ?\
*/ ltO:./6v
public Page getPage(){ YRfs8I^rg
return page; }'b3'/MJ
} _b&Mrd
FL,jlE_
/** B-@6m
* @return Returns the users. 2+s_*zM-
*/ SWNi@
publicList getUsers(){ |ITp$_S
return users; 4askQV &hj
} "
2Dz5L1v
<IC=x(T
/** 26G2. /**<
* @param page SsIy ;l
* The page to set. <%8j#@OdZ
*/ cuO(*%Is1
publicvoid setPage(Page page){ 9gZMfP
this.page = page; C},;M@xV
} w-C~
Ik
Vl%AN;o
/** 1`^l8V(
* @param users aEo!yea
* The users to set. o8-BTq8
*/ {KxeH7S
publicvoid setUsers(List users){ w4Qqo(
this.users = users; j&6,%s-M`a
} O#7ONQfBO
zH0%;
o}
/** #g#vDR!
* @param userService #v0"hFOH,
* The userService to set. *p`0dvXG2
*/ x1:+M]Da
publicvoid setUserService(UserService userService){ (v6tE[4
this.userService = userService; w},' 1
} cv=nGFx6
} Uq5wN05
I= G%r/3
ZR.1SA0x?O
ng0IRJ:3
w,bILv)
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, 5+vCuVZ
|Zr5I";
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 ;5:g%Dt
x#-uf
么只需要: UCj4%y6t
java代码: ([R}s/)$
1+~JGY#
L-hK(W!8pt
<?xml version="1.0"?> x|d Xa0=N_
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork !C
*%,Ak
es]\xw
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +0rMv
T]Gxf"mK
1.0.dtd"> C)~YWx@v
x%23oPM
<xwork> "u~l+aW0
Tf7$PSupP
<package name="user" extends="webwork-
gcqcY
a*REx_gLG
interceptors"> ]W7(}~m
a/;u:"
<!-- The default interceptor stack name Y]/(R"-2G
v_)a=I%o&2
--> 1 mhX3
<default-interceptor-ref 5L bU'5
!sQ$a#Ea
name="myDefaultWebStack"/> /=w9bUj5v
+6|Ys
<action name="listUser" ,Xs%Cg_Ig
0#lw?sv
class="com.adt.action.user.ListUser"> X0O0Y>"
<param 0,)B~|+
b#bdz1@s
name="page.everyPage">10</param> L&=j O0_
<result xT70Rp(2po
k$UgTZ
name="success">/user/user_list.jsp</result> !4GGq
</action> `*cT79
Zx,R6@l
</package> E{kh)-
AWHB^}!}
</xwork> e:hkWcV
<MZ$ baK
&dF$:$'s
Rn~FCj,-
vZj^&/F$=g
nv1'iSEeOl
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 oJe9H <
P1;T-.X~&
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。 M[ $(Pu
Qna
^Ry?6)
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !-b4@=f:
,cPNZ-%
rLs)*A!
Y^m2ealC
+N5#EpW
我写的一个用于分页的类,用了泛型了,hoho 2ME"=!&5
0JQy-hpF
java代码: 6NH.!}"G9
Eb SH)aR
@GqPU,RO
package com.intokr.util; 1{4d)z UB
[Av#Z)R
import java.util.List; @iK=1\-2
0h-holUf}~
/** biG=4?Xl
* 用于分页的类<br> Tl5K'3
* 可以用于传递查询的结果也可以用于传送查询的参数<br> zqfv|3-!}
* DrLNY"Zq
* @version 0.01 }1]/dCv
* @author cheng :bI4HXT3
*/ *6^|i}
public class Paginator<E> { 3#huC=zbf
privateint count = 0; // 总记录数 >C y
privateint p = 1; // 页编号 0l3v>ty
privateint num = 20; // 每页的记录数 ]UKKy2r.
privateList<E> results = null; // 结果 jT"P$0sJAd
WXu:mv,'e
/** eT1b88_
* 结果总数 *vv<@+gA
*/ aSd$;t~
publicint getCount(){ 1MHP#X;|
return count; m6^Ua
} @*q WV*$h
v'Ce|.;
publicvoid setCount(int count){ w]GoeIg({
this.count = count; Dww]D|M
} EW*!_|
H=])o21
/** !R;P"%PHV
* 本结果所在的页码,从1开始 '#$Y:/
* <h|XB}s+
* @return Returns the pageNo. VTk6.5!8
*/ <J-bDcp
publicint getP(){ 6TJ5G8z_
return p; &B^#?vmO
} )#k*K9[@
=BQM(mal
/** $V-]DD%Y
* if(p<=0) p=1 r_p9YS@I
* r9z_8#cR
* @param p 6~zR(HzV{
*/ ,\!4A
publicvoid setP(int p){ w{k8Y?
if(p <= 0) 5,`U3na,
p = 1; EJ{Z0R{{
this.p = p; Ze~$by|9f
} B+S
&vV
kB1]_v/
/** :khl}|
* 每页记录数量 )V~Fl$A
*/ ;~T)pG8IS
publicint getNum(){ j}XTa[
return num; Q1EY!AV8
} =2uE\6Fl,
(q`Jef
/** 5r"BavA
* if(num<1) num=1 *I%r
*/ jC+>^=J(
publicvoid setNum(int num){ B%gk[!d}8
if(num < 1) "
]
0ER
num = 1; xal,j*
this.num = num; ov: h4
} b\NWDH7}
/*p4(D_A
/** d,[.=Jqv[
* 获得总页数 ^-{ 1]G:
*/ hPr*<2mp
publicint getPageNum(){ Sxf|gDC
return(count - 1) / num + 1; nL!h hseH
} RrKAgw
a
OR}
/** k|0Fa}Z[
* 获得本页的开始编号,为 (p-1)*num+1 cw.Uy(ks|$
*/ ?GqFtNz
publicint getStart(){ uA=6 HpDB
return(p - 1) * num + 1; oc'#sE
} 2+"=i/8
.O @bX)
/** G}ElQD
* @return Returns the results. W=M&U
*/ |57KTiiNLI
publicList<E> getResults(){ /{ YUM~
return results; >0)E\_ u
} Y M{Q)115
w8:F^{
public void setResults(List<E> results){ 5~k-c Ua
this.results = results; :}x\&]uC#k
} B[ae<V0k
Ht?
u{\p@
public String toString(){ ONJW*!(
StringBuilder buff = new StringBuilder X@Eq5s
}`6-^lj
(); ^k &zX!W
buff.append("{"); I9*o[Jp5
buff.append("count:").append(count); z:9
buff.append(",p:").append(p); k/AcXU%O+
buff.append(",nump:").append(num); ]Vhhx`0
buff.append(",results:").append PN2\:l+`
fC
xN!
(results); =YF\mhMQ:
buff.append("}"); T[xGF/
return buff.toString(); RK(uC-l
} j>gO]*BX~
T'i9_V{
} toPA@V
hor ok:{
Djx9TBZ5