Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 10rGA=x'(
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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 e^GW[lT
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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 Z)A+ wM
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分页支持类: !VHIl&Mos
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java代码: ."X~?Nk
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package com.javaeye.common.util; rsv!mY,Em
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import java.util.List; lnWiE}F
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publicclass PaginationSupport { orHD3T%&
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publicfinalstaticint PAGESIZE = 30; 0_
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privateint pageSize = PAGESIZE; D:E_h
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privateList items; HdUW(FZ
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privateint totalCount; BmFME0
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privateint[] indexes = newint[0]; E`n`#=xKR
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privateint startIndex = 0; ^6oqq[$
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public PaginationSupport(List items, int g<4M!gi
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totalCount){ KdJx#Lc
setPageSize(PAGESIZE); TQd FC\@f"
setTotalCount(totalCount); u2BW]T]
setItems(items); ><MgIV
setStartIndex(0); h&M
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} _`{{39 F
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public PaginationSupport(List items, int .0E4c8R\X
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totalCount, int startIndex){ <`_OpNxqW
setPageSize(PAGESIZE); !K3cf]2UD
setTotalCount(totalCount); {kl{mJ*
setItems(items); s]vJUC,s
setStartIndex(startIndex); <o7#?AcPu
} ~1r*/@M[V
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public PaginationSupport(List items, int |id79qY7g
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totalCount, int pageSize, int startIndex){ 8C,utjy
setPageSize(pageSize); )g:,_ 1s)|
setTotalCount(totalCount); MupW=3.38
setItems(items); {/A)t1nL
setStartIndex(startIndex); iQzX-a|4]
} d6@jEa-
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publicList getItems(){ 27],O@2?L
return items; +:]Aqyc\
} ow+Dd[i
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publicvoid setItems(List items){ y{`(|,[
this.items = items; (OyY_`
} &[ u6oAR
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publicint getPageSize(){ 8gbm "!
return pageSize; _:gGD8
} s1Tl.p5
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publicvoid setPageSize(int pageSize){ qHR^0&
this.pageSize = pageSize; XiRT|%j
} g{v5mly
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publicint getTotalCount(){ "37@Zt
return totalCount; 0Z
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} RO%tuU,-
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publicvoid setTotalCount(int totalCount){ sWsG,v_
if(totalCount > 0){ "y~muE:.
this.totalCount = totalCount; 1<W4>~,wj
int count = totalCount / O2q=gYX>\
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pageSize; @L[PW@:SZ
if(totalCount % pageSize > 0) oEenm\ZI
count++; c?.r"5#
indexes = newint[count]; \ W
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for(int i = 0; i < count; i++){ &e-#|p#v
indexes = pageSize * '9-axIj70
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} {d 1N&
}else{ %tzN@
this.totalCount = 0; ~?AC:
} M<{5pH(K
} 3$?9uMl#
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publicint[] getIndexes(){ !,Xyl}
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return indexes; W;Ud<7<;Z
} &/>;LgN
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publicvoid setIndexes(int[] indexes){ +36H%&!
this.indexes = indexes; UAsF0&]
} t]
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publicint getStartIndex(){ cWN d<=Jp
return startIndex;
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} _M8G3QOx
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publicvoid setStartIndex(int startIndex){ IL~]m?'V(
if(totalCount <= 0) K1?Z5X(b
this.startIndex = 0; ?^%YRB&
elseif(startIndex >= totalCount) VHXI@UT*
this.startIndex = indexes V";mWws+?#
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[indexes.length - 1]; 2[jL^XMM
elseif(startIndex < 0) Ik`O.Q.}
this.startIndex = 0; |-~b$nUe
else{ f{)+-8
this.startIndex = indexes _1I K$gb[
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[startIndex / pageSize]; 9@:BK;Fi
} $ q%mu
} 'e}uvbK
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publicint getNextIndex(){ `wNm%*g
int nextIndex = getStartIndex() + GwcI0~5
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pageSize; #v{ Y=$L
if(nextIndex >= totalCount) `TUZZz
return getStartIndex(); sW
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else $aB/+,
return nextIndex; T!MZ+Ph`F
} ~mtTsZc
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publicint getPreviousIndex(){ AT"!{Y "H
int previousIndex = getStartIndex() - ZTN(irK
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pageSize; js~tKUvg
if(previousIndex < 0) GxxDY]!
return0; yH*hL0mO
else G 0hYFc u
return previousIndex; <>%,}j
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} &,J*_F<s2<
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} )D;*DUtMVm
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抽象业务类 m#JI!_~!
java代码: cv2]*
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/** qpI]R
* Created on 2005-7-12 FKC\VF
*/ k}GjD2m
package com.javaeye.common.business; 62Mdm3
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import java.io.Serializable; >-M ]:=L
import java.util.List; Av o|v>
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import org.hibernate.Criteria; e&0K;yU
import org.hibernate.HibernateException; v9=}S\=Cd
import org.hibernate.Session; {Bh("wg$Lk
import org.hibernate.criterion.DetachedCriteria; r$ =qQ7^#
import org.hibernate.criterion.Projections; b^x07lO
import #Q}_e7t
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org.springframework.orm.hibernate3.HibernateCallback; =Q-k'= 6\
import eX"''PA
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org.springframework.orm.hibernate3.support.HibernateDaoS ?1peF47Z
}# Doy{T
upport; Mu{BUtkzG
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import com.javaeye.common.util.PaginationSupport; "k:=Y7Dx
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public abstract class AbstractManager extends aE)by-'
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HibernateDaoSupport { /ylc*3e'4
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privateboolean cacheQueries = false; "UG
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privateString queryCacheRegion; e4\dpvL
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publicvoid setCacheQueries(boolean b*EXIzQ
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cacheQueries){ C5*xQlCq}
this.cacheQueries = cacheQueries; zXZir7NfM
} irKIy
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publicvoid setQueryCacheRegion(String \S4SI
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queryCacheRegion){ fvqd'2 t
this.queryCacheRegion = 2'|8Q\,:4Z
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queryCacheRegion; .tnkT;T
} I4t*?
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publicvoid save(finalObject entity){ n?xTkkr0
getHibernateTemplate().save(entity); -Q"hZ 9
} o6a0'vU><
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publicvoid persist(finalObject entity){ )d`mvZBn1
getHibernateTemplate().save(entity); ?X9UTOx
} 86
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publicvoid update(finalObject entity){ $_Nf-:D*
getHibernateTemplate().update(entity); fjG&`m#"
} =qu(~]2(
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publicvoid delete(finalObject entity){ 33Az$GXFsq
getHibernateTemplate().delete(entity); IG ~`i I
} /=: j9FF
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publicObject load(finalClass entity, 5B4Ssrs5W~
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finalSerializable id){ w@-M{?R
return getHibernateTemplate().load B?bW1
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(entity, id); |nUl\WRd\
} ";SiL{Z
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publicObject get(finalClass entity, >ut" OL9J
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finalSerializable id){ j<<3Pr
return getHibernateTemplate().get }UwO<#
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(entity, id); \ 0W!4D
} !69&Ld
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publicList findAll(finalClass entity){ o 5U(i
return getHibernateTemplate().find("from =c.5874A`
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" + entity.getName()); zi9[)YqxPH
} =q7Z qP
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publicList findByNamedQuery(finalString 4<dcB@v
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namedQuery){ K<`osdp=&
return getHibernateTemplate tJViA`@x
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().findByNamedQuery(namedQuery); F,BOgWwP
} -VKS~{
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publicList findByNamedQuery(finalString query, #G" xNl
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finalObject parameter){ Hb} X-6N
return getHibernateTemplate IYn]U4P.
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().findByNamedQuery(query, parameter); _|[UI.a
} ~c^>54
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publicList findByNamedQuery(finalString query, M>9-=$7
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finalObject[] parameters){ KqBk~-G
return getHibernateTemplate DI+]D~N
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().findByNamedQuery(query, parameters); x3jb%`o#!
} 0sN.H=
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publicList find(finalString query){ $3`>{3x$
return getHibernateTemplate().find m(RXJORI
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(query); .+7;)K
} xh7c VE[UM
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publicList find(finalString query, finalObject Tc8un.
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parameter){ &j(+ /;A
return getHibernateTemplate().find G9g1hie@%
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(query, parameter); d>;&9;)H
} ~gB>) ]
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public PaginationSupport findPageByCriteria 'smWLz}
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(final DetachedCriteria detachedCriteria){ nKW*Y}VO
return findPageByCriteria Ee`1F#c
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); kOIt(e
} :ba5iMa
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public PaginationSupport findPageByCriteria ,%\o4Rc'o
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(final DetachedCriteria detachedCriteria, finalint W6On93sa
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startIndex){ A&nU]R8S
return findPageByCriteria ^]{R.(#z
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(detachedCriteria, PaginationSupport.PAGESIZE, <.Nx[!'~&d
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startIndex); |SyMngIY
} %-d]X{J:
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public PaginationSupport findPageByCriteria Pp )3(T:
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(final DetachedCriteria detachedCriteria, finalint 9K9DF1SOa
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pageSize, <~ Sz04
finalint startIndex){ aH^RoG}
return(PaginationSupport) E9;|'Vy<E
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getHibernateTemplate().execute(new HibernateCallback(){ ANgw"&&>(
publicObject doInHibernate K_dOq68_
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(Session session)throws HibernateException { F&&$Qn_+
Criteria criteria = x
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detachedCriteria.getExecutableCriteria(session); By% =W5
int totalCount = k{'0[,mx#
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((Integer) criteria.setProjection(Projections.rowCount 9(@\&>)
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()).uniqueResult()).intValue(); =5\|[NSK-
criteria.setProjection 3D2E?$dX
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(null); ?mwD*LN3o
List items = y3h/IpT
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criteria.setFirstResult(startIndex).setMaxResults ONe# rKJ_
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(pageSize).list(); X-wf:h?i
PaginationSupport ps = a[ex[TRKe
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new PaginationSupport(items, totalCount, pageSize, 92 [;Y
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startIndex); sQ
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return ps; zzyHoZJP
} 7x@A%2J
}, true); d!$Z(W0
} q}]XYys
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public List findAllByCriteria(final l g-X:Z.
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DetachedCriteria detachedCriteria){ $g
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return(List) getHibernateTemplate v#!%GEg1r
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().execute(new HibernateCallback(){ <"_d]?,
publicObject doInHibernate :$n=$C-wp
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(Session session)throws HibernateException { ^pYxKU_O
Criteria criteria = uH(f$A
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detachedCriteria.getExecutableCriteria(session); PF53mUs4
return criteria.list(); pim!.=vN/U
} R.yC(r
}, true); )/wk( O+
} ?W)A
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public int getCountByCriteria(final Vb= Mg
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DetachedCriteria detachedCriteria){ WUh$^5W
Integer count = (Integer) @CT;g\4
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getHibernateTemplate().execute(new HibernateCallback(){ zlEX+=3
publicObject doInHibernate c\Q7"!e
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(Session session)throws HibernateException { =,UWX3`f
Criteria criteria = MZT23[+
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detachedCriteria.getExecutableCriteria(session); "\3B^ e,
return [@5Ytv H
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criteria.setProjection(Projections.rowCount 28UU60
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()).uniqueResult(); iT%} $Lu~
} * /:x sI
}, true); orjj'+;X
return count.intValue(); |\7
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} Yo|,]X>/
} %@6}GmK^
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用户在web层构造查询条件detachedCriteria,和可选的 '2[albxSc
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~2gG(1%At9
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PaginationSupport的实例ps。 ]% IT|/;9Y
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ps.getItems()得到已分页好的结果集 @n{JM7ctJ
ps.getIndexes()得到分页索引的数组 H*$jc\
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ps.getTotalCount()得到总结果数 qLB)XnQ
ps.getStartIndex()当前分页索引 Y7*U:I+N
ps.getNextIndex()下一页索引 3_MS.iM
ps.getPreviousIndex()上一页索引 (A~/ '0/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 E: $P=%b
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 &C"L
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一下代码重构了。 7aQc=^vaZ
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我把原本我的做法也提供出来供大家讨论吧: |4uWh
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首先,为了实现分页查询,我封装了一个Page类: 4 Dw@r{
java代码: L_wk~z
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/*Created on 2005-4-14*/ D0%Ug>
package org.flyware.util.page; !3 f?:M
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/** z6w3"9Um
* @author Joa dAkgR~
* /Q2mMSK1h
*/ A8oo@z68n>
publicclass Page { (}EB2V9Hh
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/** imply if the page has previous page */ ^7 &5
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privateboolean hasPrePage; }}>q2y
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/** imply if the page has next page */ =p=rg$?
privateboolean hasNextPage; ~==>pj
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/** the number of every page */ P#XID 2;
privateint everyPage; ^w c"&;=c|
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/** the total page number */ 3
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privateint totalPage; &'}RrW-s
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/** the number of current page */ .tzG_
privateint currentPage; qx4I_%
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/** the begin index of the records by the current f v9V7
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query */ Db1pW=66:
privateint beginIndex; ,kF}lo)
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/** The default constructor */ |qmu_x\
public Page(){ -Ty*aov
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} }#Qc \eud
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/** construct the page by everyPage Ooq! 0g
* @param everyPage 'zGo?a
* */ D(H>R&b!
public Page(int everyPage){ UmclTGn
this.everyPage = everyPage; ~?FpU
} B9H@e#[
NwG= <U*
/** The whole constructor */ 6w(6}m.L^
public Page(boolean hasPrePage, boolean hasNextPage, 9)gC6IiW
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int everyPage, int totalPage, Q&eQQ6b^Ih
int currentPage, int beginIndex){ DFd%9*N
this.hasPrePage = hasPrePage; 4y'OMRy
this.hasNextPage = hasNextPage; 7El[ >
this.everyPage = everyPage; ,]cD
this.totalPage = totalPage; _cJ2\`M
this.currentPage = currentPage; x`dHJq`_g
this.beginIndex = beginIndex; 8qEVOZjV&
} -OA?BEQ=I
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/** )l[M
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* @return $a"n1ou
* Returns the beginIndex. |Clut~G
*/ ?hWwj6i&
publicint getBeginIndex(){ %d(^d
return beginIndex; a8i]]1Blz
} *EZHJt9
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/** Xp8]qH|K
* @param beginIndex Q'YH>oGh^
* The beginIndex to set. 8$ma;U d
*/ ]b%Hy
publicvoid setBeginIndex(int beginIndex){ ^*S)t.
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this.beginIndex = beginIndex; NNE<L;u
} }`v~I4i
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/** bV$)!]V
* @return jlBanGs?
* Returns the currentPage. Y<Xz
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*/ k25WucQ
publicint getCurrentPage(){ fe_yqIdk
return currentPage; dUF&."pW e
} ;r>snJ=M
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/** 4)"n
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* @param currentPage %d>=+Ds[
* The currentPage to set. `>?ra-
*/ b r^_'1
publicvoid setCurrentPage(int currentPage){ -Gw$#!
this.currentPage = currentPage; o_D?t-XH
} C_n9T{k
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/** 0LfU=X0#7
* @return k7>|q"0C
* Returns the everyPage. & M~`:R
*/ HKqwE=NZ
publicint getEveryPage(){ v}tag#f5>?
return everyPage; |iR T!
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} $T`<Qq-r
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/** F^5?\
* @param everyPage LwK+:4$
* The everyPage to set. 8&Oa_{1+Q
*/ 0qo)."V{
publicvoid setEveryPage(int everyPage){ -Y*bSP)\
this.everyPage = everyPage; #DN0T' B
} 1\g6)|R-+
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/** C":o/;,1
* @return wmTq` XH)
* Returns the hasNextPage. 05spovO/'
*/ r4QxoaM
publicboolean getHasNextPage(){ EC\yzH*X
return hasNextPage; @~#Ym1{W
} Ci<ATho
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/** )*Q-.Je/U
* @param hasNextPage *=wYuJ#
* The hasNextPage to set. FI<q@HF
*/ BWM YpZom
publicvoid setHasNextPage(boolean hasNextPage){ :sP!p`dl
this.hasNextPage = hasNextPage; sp
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} CXO2N1~(J
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/** 9:!gI|C
* @return <7n4_RlF!
* Returns the hasPrePage. j8n4fv-)f
*/ 7yz4'L
publicboolean getHasPrePage(){ ]b= P=
return hasPrePage; .p=sBLp8
} m@Qt.4m%g
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/** hTM[8 ~<^
* @param hasPrePage 8-lOB
* The hasPrePage to set. \|U l]1pO8
*/ J%jB?2
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publicvoid setHasPrePage(boolean hasPrePage){ *$"gaXI
this.hasPrePage = hasPrePage; VL/|tL>E^
} u@.>Z{h
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/** @0eHS+
* @return Returns the totalPage. K^ 3co
* qBQ`~4s
*/ C-?%uF
publicint getTotalPage(){ `D":Q=:
return totalPage; W?We6.%
} \y88d4zX
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/** )
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* @param totalPage nD0}wiL{
* The totalPage to set. #!9S}b$
*/ v|ck>_"
.
publicvoid setTotalPage(int totalPage){ 78Aa|AJU
this.totalPage = totalPage; D!oc>K$B
} V=X:=
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} "ywh9cp
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 a2f^x@0k
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个PageUtil,负责对Page对象进行构造: 9M /SH$Qy
java代码: `$YP<CJeq
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/*Created on 2005-4-14*/ z**hD2R!
package org.flyware.util.page; 3s:%2%jVK
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import org.apache.commons.logging.Log; 3loY qeP
import org.apache.commons.logging.LogFactory; NJ MJ
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/** LrCk*@
* @author Joa n q19Q)
* ,zQOZ'^
*/ ow/57P
publicclass PageUtil { fRvAKz|rL
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privatestaticfinal Log logger = LogFactory.getLog =l9T7az
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(PageUtil.class); Pz_NDI
}Z`(aDH
/** @cq`:_.[
* Use the origin page to create a new page -/D|]qqHm
* @param page Ao7 `G':
* @param totalRecords vU*x2fVb}
* @return _0pO8o-x
*/ %vO<9fE|1
publicstatic Page createPage(Page page, int %5
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totalRecords){ ;$BdP7i:
return createPage(page.getEveryPage(), ^# A.@
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page.getCurrentPage(), totalRecords); ?`zgq>R}w[
} #)`A7 $/,
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/** L7mz#CMWf
* the basic page utils not including exception O4No0xeWo
~ ~8rI[/
handler !RlC~^
-
* @param everyPage WA)Ij(M8 p
* @param currentPage sl/)|~3!8
* @param totalRecords )~rB}>^Z
* @return page z}.D"
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*/ WjM>kWv
publicstatic Page createPage(int everyPage, int =f:(r'm?r.
>!9h6BoGV
currentPage, int totalRecords){ -U>7
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everyPage = getEveryPage(everyPage); !Zbesp KZ
currentPage = getCurrentPage(currentPage); m&R"2t_Z
int beginIndex = getBeginIndex(everyPage, RP(/x+V
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currentPage); b0a}ME&1
int totalPage = getTotalPage(everyPage, "]t>ZT:OJ
(Q-I8Y8l8
totalRecords); OCHm;
boolean hasNextPage = hasNextPage(currentPage, vZajT!h
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totalPage); [BBpQN.^q6
boolean hasPrePage = hasPrePage(currentPage); /qxJgoa
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returnnew Page(hasPrePage, hasNextPage, 4R +P
everyPage, totalPage, R I@*O6\/I
currentPage, E' %lxr
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beginIndex); z };ZxN
} 8mgQu]>
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privatestaticint getEveryPage(int everyPage){ B4O6>'
return everyPage == 0 ? 10 : everyPage; p,n\__
} .^XHuN&
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privatestaticint getCurrentPage(int currentPage){ "g
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return currentPage == 0 ? 1 : currentPage; Sl.o,W^
} w3#`1T`N
a{`"68
privatestaticint getBeginIndex(int everyPage, int #'>?:k
4uX(_5#j
currentPage){ m4gU*?
return(currentPage - 1) * everyPage; <F=Dj*]
} /S/aUvN
6;JP76PD
privatestaticint getTotalPage(int everyPage, int 5.k}{{+
VD#!ztcY'
totalRecords){ \Hs|$
int totalPage = 0; Bn-J_-%M
CT}' ")Bm
if(totalRecords % everyPage == 0) hNO)~rt
totalPage = totalRecords / everyPage; Ofm5[q=
else IIaxgfhZ
totalPage = totalRecords / everyPage + 1 ; n{=7 yK
dwp:iM
return totalPage; h]P/KVqR.
} XTj73 MWY
Xb+3Xn0}&8
privatestaticboolean hasPrePage(int currentPage){ MOyT< $
return currentPage == 1 ? false : true; }Z-I2
=]
} `Z8^+AMc
s$3`X(Pn
privatestaticboolean hasNextPage(int currentPage, </yo9.
6+Jry@
int totalPage){ S*rO0s:
return currentPage == totalPage || totalPage == =43d%N
M1(9A>|nF
0 ? false : true; A^cU$V%?W
} 3"vRK5Bf
,|iy1yg(
7(@(Hm
} ~T&%
VvI
G)~MbesJ
g 9|qbKQ:[
/4H[4m]I
}\4p3RQrz
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。 I<xy?{s
(s Jq;Z
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 YnD#p[Wo^
a6qwL4
做法如下: =
uk`pj[l
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 WCoF{*
X
[!X>w&z|
的信息,和一个结果集List: ,wlbIl~
java代码: Tr$i=
M
'5V^}/
T aEt
/*Created on 2005-6-13*/ }z?xGW/k
package com.adt.bo; b^%?S8]h
fZ{&dslg
import java.util.List; aSTFcz"
h*G#<M
import org.flyware.util.page.Page; o|+E+l9\
IJldN6&\q
/** K Ka c6Zj
* @author Joa Gxo#
!
*/ l3BD
<PB2S
publicclass Result { hc6.#~i
}}s8D>;G~
private Page page; [pr 9 $Jr
V8\$`NEP
private List content; %
<^[j^j}o
-!i;7[N
/** 6GY32\Ac
* The default constructor j=FMYd8$y
*/ 70duk:Ri0
public Result(){ w[e0wh`.
super(); yB=C5-\F
} R04.K!
8g.AT@ ,Q
/** <sO?ev[
* The constructor using fields NoJUx['6
* bd} r#^'K
* @param page HgYc@P*b
* @param content DL
%S(l
*/ )\D2\1e(c
public Result(Page page, List content){ l_bL,-|E8
this.page = page; FPvuzBJ
this.content = content; KlY,NSlQ
} zjea4>!A2
Z+r%_|kZ
/** *Yj~]E0`1
* @return Returns the content.
.V8/ELr]
*/ Qk+=znJ
publicList getContent(){ t'dHCp}
return content; ?]s%(R,B5
} '`9%'f)
U~oBNsU"
/** ;I[ht
* @return Returns the page. xOwNCh
*/
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public Page getPage(){ g8LT7
return page; zhuyePn
} I/mvQxp
r hiS
/** ;RNM
* @param content : :F!
* The content to set. O|HIO&M
*/ f<g>dQlE
public void setContent(List content){ UN-T^
this.content = content; +R2^*
*<
} F5<"ktnI
uo]Hi^r.l
/** 8FB\0LA!g
* @param page t9?R/:B%
* The page to set. ~!8%_J _
*/ &=v/VRan[
publicvoid setPage(Page page){ R#"U/8b>z
this.page = page; }%-UL{3%
} -@YVe:$%b
} ^^n+
\Ku9"x
kb/|;!
v9Z lNA7m!
C>.]Bvg
2. 编写业务逻辑接口,并实现它(UserManager, bHhC56[M
<{$ev&bQ
UserManagerImpl) :*mA,2s
java代码: cEDDO&u
DCEvr" (
skk-.9
/*Created on 2005-7-15*/ c'4>D,?1
package com.adt.service; =giM@MV
F3kC"H
import net.sf.hibernate.HibernateException; 1$:{{%
D}zOuB,S
import org.flyware.util.page.Page; }ZEfT]
k)H[XpM
import com.adt.bo.Result; YWt"|
OSSd;ueur$
/** "wT~$I"
* @author Joa iYO
wB'z
*/ uB5h9&57
publicinterface UserManager { j[$B\H
[47K7~9p
public Result listUser(Page page)throws `A4QU,0
8h
5;3c<
HibernateException; ATYQ6E[{MV
Nw9-pQ
} )'BJ4[aq\
ka?IX9t\
pm'@2dT
Bq$e|t)'
E3CiZ4=5
java代码: Gt\K Ln
&rl]$Mtt
$I}Hk^X
/*Created on 2005-7-15*/ )8 "EI-/.
package com.adt.service.impl; W2r6jm!
:$SRG^7md
import java.util.List; EzD
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G1#Bb5q:
import net.sf.hibernate.HibernateException; [a>JG8[,t
9A/Kn]s(jj
import org.flyware.util.page.Page; ps!5HZ2:
import org.flyware.util.page.PageUtil; ^*cMry
VgFF+Eg
import com.adt.bo.Result; e'/
import com.adt.dao.UserDAO; t6<sNzF&
import com.adt.exception.ObjectNotFoundException;
:f?,]|]+-
import com.adt.service.UserManager; X] JpS
LH3N}J({
/** *O(/UVuD\
* @author Joa bMqu5G_q
*/ @n~>j&Kp
publicclass UserManagerImpl implements UserManager { m'Ek p
F$6])F
private UserDAO userDAO; O, ``\(P
<\}Y@g8
/** e\d5SKY
* @param userDAO The userDAO to set. i">z8?qF
*/ rx}ujjx
publicvoid setUserDAO(UserDAO userDAO){ pU:C=hq4
this.userDAO = userDAO; 6PzN>+t^y
} DmXDg7y7s
6uCk0
B|
/* (non-Javadoc) MuFU?3ovG*
* @see com.adt.service.UserManager#listUser o/x5
j^aQ>(t(9
(org.flyware.util.page.Page) /,rF$5G,
*/ pE(<XD3Q
public Result listUser(Page page)throws '&pf
s!j(nUd/
HibernateException, ObjectNotFoundException { {0)WS}&
int totalRecords = userDAO.getUserCount(); B(en5|
if(totalRecords == 0) (v'lb!j^#
throw new ObjectNotFoundException _} X`t8L h
k@t,[
("userNotExist"); 9s\i(/RxW
page = PageUtil.createPage(page, totalRecords); pzt Zb
List users = userDAO.getUserByPage(page); $@u^Jt, ?
returnnew Result(page, users); -aH?7HV}
} CJ}@R.Zy
J++sTQ(!?
} l9ifUhe
+4:+qGAJ{
LKqog%,c
}lNufu
4M0v1`k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ek{PA!9Sk
vY0V{u?J
询,接下来编写UserDAO的代码: ~U7\ LBF
3. UserDAO 和 UserDAOImpl: #nc@!+
java代码: jC/JiI
5>1Y="B
jzJ1+/9
/*Created on 2005-7-15*/ E?m#S
package com.adt.dao; WW\)B-}T
/qkIoF2
import java.util.List; >nIcFm
<E}]t,'3
import org.flyware.util.page.Page; p\]LEP\z,
bZOy~F|
import net.sf.hibernate.HibernateException; tFST.yT>zg
R8r[;u\iV
/** <0Egkz3s
* @author Joa 0p>:rU~
*/ WH*=81)zp
publicinterface UserDAO extends BaseDAO { ZvnZ}t>?
,~N+?k_
publicList getUserByName(String name)throws dW^_tzfF7
<j8&u/Za~'
HibernateException; z7Rcnr;
2W:?#h3
publicint getUserCount()throws HibernateException; u&d v[
%}]4Nsd e
publicList getUserByPage(Page page)throws i;'X}KW
(+Kof
HibernateException; hzPB~obC
@8M2'R\
} .Qi1I
hIO4%RQj_
$:gSc&mx
SSsQu^A
!q6V@&
java代码: ~lalc ^
\PMKmJX0O
,Qi|g'a
/*Created on 2005-7-15*/ g@6X|W5,J
package com.adt.dao.impl; X3=Jp'p$h
vb ^!(
import java.util.List; CT:eV7<>s
UE`4$^qs
import org.flyware.util.page.Page; H.mQbD`X
?eVuz x
import net.sf.hibernate.HibernateException; rIWN!@.J
import net.sf.hibernate.Query; ,N|R/Vk$+E
4k2c mM$
import com.adt.dao.UserDAO; FQ~ead36C
rB&j"p}Q
/** bvu<IXX=2
* @author Joa ~Ow23N
*/ "`gZy)E
public class UserDAOImpl extends BaseDAOHibernateImpl "JLhOTPaHf
kR~4O$riG
implements UserDAO { qjEWk."
jc~*#\N
/* (non-Javadoc) 2c`=S5
* @see com.adt.dao.UserDAO#getUserByName VJtTbt;>
+-YuBVHL
(java.lang.String) DoB3_=yJ+
*/ QDT{Xg*I
publicList getUserByName(String name)throws XoQk'7"f
qkG;YGio
HibernateException { CJtjn
String querySentence = "FROM user in class `iayh
Odjd`DD1
com.adt.po.User WHERE user.name=:name"; $`dNl#G,
Query query = getSession().createQuery {)gd|JV*
QpTNU.v5f
(querySentence); TvG:T{jwy
query.setParameter("name", name); '2J6%Gg
return query.list(); +rpd0s49
} |laKntv 2
=X5&au o
/* (non-Javadoc) ^PR,TR.
* @see com.adt.dao.UserDAO#getUserCount() D!T4k]^
*/ \HEo8~TY
publicint getUserCount()throws HibernateException { -2ij;pkIW$
int count = 0; Qr-J-2s ?B
String querySentence = "SELECT count(*) FROM *vE C,)
K2K6
user in class com.adt.po.User"; A.x}%v,E
Query query = getSession().createQuery mXM>6>;y
FY}*Z=D%
(querySentence); D2cIVx3:(
count = ((Integer)query.iterate().next f>/ 1KV
dq/?&X
()).intValue(); &u\z
T
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return count; Y4!q 1]TGX
} VgTI2
TZyQOjUu
/* (non-Javadoc) `+;oo B
* @see com.adt.dao.UserDAO#getUserByPage d;:&3r|X
|&']ms5J
(org.flyware.util.page.Page) ?JTyNg4<
*/ )&!@O$RS8(
publicList getUserByPage(Page page)throws h`rjD d
G-?9;w'@
HibernateException { <+,0G`
String querySentence = "FROM user in class na:^7:I
}v,P3
com.adt.po.User"; CyDf[C)=
Query query = getSession().createQuery (jFE{M$-
B{(l5B6
(querySentence); 2Lgvy/uN
query.setFirstResult(page.getBeginIndex()) 2e@\6l,!^
.setMaxResults(page.getEveryPage()); w=o m7%J@l
return query.list(); '[8jm=Q#'
} tvxcd*{
Qs X 59d
} rL3Vogw'e
.: ;Hh~
K -1~K
bY$!"b~
{;M/J
至此,一个完整的分页程序完成。前台的只需要调用 <r3n?w8
(kOv
userManager.listUser(page)即可得到一个Page对象和结果集对象 k T>}(G||
_'p;V[(+M
的综合体,而传入的参数page对象则可以由前台传入,如果用 gdNp2b
6WM_V9Tidq
webwork,甚至可以直接在配置文件中指定。 ;#yz i2f
^:ngHue8~
下面给出一个webwork调用示例: 'qS!n
java代码: .tsB$,/
nDw9
y36aoKH
/*Created on 2005-6-17*/ $Ws2g*i
package com.adt.action.user; bkI A:2HX
~J:lCu
import java.util.List;
(9|K}IM:
Te#[+B?
import org.apache.commons.logging.Log; JdEb_c3S
import org.apache.commons.logging.LogFactory; sH: &OaA
import org.flyware.util.page.Page; '#6DI"vJ
R~-q!nC
import com.adt.bo.Result; vb!KuI!:p
import com.adt.service.UserService; CFxs`C^
import com.opensymphony.xwork.Action; _nq n|
{v(|_j&:o
/** ,CF~UX%
bU
* @author Joa ~zRd||qv
*/ u\?u}t v
publicclass ListUser implementsAction{ M
-TK
P'k39
privatestaticfinal Log logger = LogFactory.getLog A79SAheX#
UU`qI}Ys8F
(ListUser.class); 8+F2
!IM
0AenDm@9
private UserService userService; -+/|
g'E^@1{
private Page page; PeaD]
4R6 .GO
privateList users; rD?o97
9,+LNZ'k
/* m^KkS
* (non-Javadoc) u}_q'=<\
* *L_wRhhk
* @see com.opensymphony.xwork.Action#execute() }e)ltp|
*/ p*A//^wQ
publicString execute()throwsException{ &(0);I@fc
Result result = userService.listUser(page); >EjBknl
page = result.getPage(); mi?Fy0\
users = result.getContent(); d1N&J`R\1
return SUCCESS; ;$]R#1i44
} UQy+&;#5
EIAT*l :NW
/** oT w1w
* @return Returns the page. hQO~9mQ+!
*/ V-57BKeDz
public Page getPage(){ ~ nIZg5
return page; j43HSY7@
} ?(N(8)G1
JaEyVe
/** @ggM5mm
* @return Returns the users. X|as1Y$O+
*/ }v{F9dv
publicList getUsers(){ %3cBhv[q4
return users; 4Y'qoM;
} 3ul
quR':=S5f
/** g6S8@b))|
* @param page mGX;JOjZ
* The page to set. cuHs`{u@P
*/ I]h+24_S
publicvoid setPage(Page page){ Q"\[ICu!,
this.page = page; ITTC}
} _\"?:~rUN
a)xN(xp##
/** ^#%[
* @param users 8d]=
+n!
* The users to set. &*0V!+#6
*/ J{91 t |
publicvoid setUsers(List users){ ][9M_.
this.users = users; Yq.Omr!
} (mycUU%
[KJm&\evp
/** N$.''D?7D
* @param userService tNtP+v-{
* The userService to set. $0WAhq
*/ 5(,WN
publicvoid setUserService(UserService userService){ #3.\}d)
this.userService = userService; -7lJ
} 4aGHks8Z,\
} |_-FQ~Hf F
H|Eu,eq-E
^<<
Wqmx
'&\km~&
p%n}a%%I
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ")TI,a`
J,k{Bm
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 6$IAm#
\wMr[_LW
么只需要: =oSv=xY
java代码: G.9?ApG9
d6_ CsqV
#T+%$q [:
<?xml version="1.0"?> ~$+9L2gz
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1Azigd0%
m'Wz0b^BO
1.0//EN" "http://www.opensymphony.com/xwork/xwork- G|.>p<q
C8i}~x<
1.0.dtd"> ($]y*|Obn
RTSg=
<xwork> 5pz%DhjLo
NoV2<m$
<package name="user" extends="webwork- XjWoUnz
7j5 l?K-
interceptors"> *V>Iv/(
>Efv?8$E\
<!-- The default interceptor stack name }9jy)gF*e
TR]~r2z
--> ,xNuc$8Jd
<default-interceptor-ref Hw_(Af?C
fH>]>2fS
name="myDefaultWebStack"/> J
v'$6[?
m>~%.
(/x
<action name="listUser" ^b'|`R+~}
2\W[ ItxL0
class="com.adt.action.user.ListUser"> (@~d9PvB>
<param q*,];j/>k
crUt8L-B4
name="page.everyPage">10</param> pGh2 4E
<result j$a,93P5
g*TAaUs|n
name="success">/user/user_list.jsp</result> 0 @~[SXR
</action> O:WFh;c
`A])4q$
</package> =.f]OWehu.
Q&rpW:^v
</xwork> nJNdq`y2
Y]Td+Zi
9=89)TrY
](vOH#E
CQ9B;i`
@;!s"!~sv
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 \E5%.KR
7g[T#B'/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。 HI*xk
FT!|YJz<K
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 LcI,Dy|P
=rFgOdj
"WV]|
TS"]
@.6l^"L
<p;cR` %uE
我写的一个用于分页的类,用了泛型了,hoho K\v1o
18jI6$DY
java代码: Xkk m~sM6
3@f@4t@5V
E`}KVi57
package com.intokr.util; X!KjRP\\
<E[X-S%&
import java.util.List; 3iMh)YH5b
M#c.(QdF
/** >vF=}1_L
* 用于分页的类<br> n.Iu|,?q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> J39,x=8LL
* t:X\`.W
* @version 0.01 GdVq+,Ge
* @author cheng x>TH yY[sq
*/ ]~iOO
%&R
public class Paginator<E> { OsAH!e
privateint count = 0; // 总记录数 4RTuy+
M
privateint p = 1; // 页编号 `'H"|WsT
privateint num = 20; // 每页的记录数 #0V$KC*>
privateList<E> results = null; // 结果 o*& D;
O:3LA-vA
/** rP Wn
* 结果总数 zBg>I=hiG
*/ KAH9?zI)M
publicint getCount(){ bq{":[a
return count; PZmg7N
} x2/L`q"M?=
?UuJk
publicvoid setCount(int count){ UT!gAU
this.count = count; ?$T!=e"
} g(){wCI
*<Yn
/** MW*@fl<@?M
* 本结果所在的页码,从1开始 OCIWQ/
P
* }#va#Nb(,
* @return Returns the pageNo. n<\
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*/
&0! f_
publicint getP(){ p(dJf&D
return p; e}>8rnR{
} g#b[-)Qx
NGZEUtj
/** "|<6bA
* if(p<=0) p=1 gw[\7
* xdw"JS}
* @param p ')ZxWYT
O^
*/ baJ(Iy$XT
publicvoid setP(int p){ T*YbmI]4
if(p <= 0) 4pNIsjl}
p = 1; pd2Lc
$O@
this.p = p; g%z'#E97
} 6~g`B<(?
/Xa_Xg7
/** 1 ?X(q
* 每页记录数量 K6"#&0
*/ ;\~{7 9c
publicint getNum(){ =fk+"!-i%"
return num; : V16bRpjL
} LS1r}cl
UykOQ-2-n
/** !J<}=G5
* if(num<1) num=1 fu3~W
*/ m=;0NLs4
publicvoid setNum(int num){ L%4[,Rsw
if(num < 1) (Ic{C5'
num = 1; [X>\!mt
this.num = num; `U:W (\L
} ch2Q k8
(Uk1Rt*h
/** Tc{r;:'G<
* 获得总页数 cspO5S>#
*/ N~I2~f
publicint getPageNum(){ c6zghP3dR
return(count - 1) / num + 1; *5KV DOd
} B<)c{kj
="%nW3e@
/** #'"zyidu
* 获得本页的开始编号,为 (p-1)*num+1 :|%dV}j
*/ <
H1+qN=]`
publicint getStart(){ l+# l\q%l
return(p - 1) * num + 1; 4yLC
} |a!AgvNF
FFE IsB"9
/** :=J~t@
* @return Returns the results. ;qM
I3 wF
*/ ,PG d
publicList<E> getResults(){ 9Z! j
return results; LR :Qb]|"
} R7'a/
{\tHS+]
public void setResults(List<E> results){ \;"$Z9W
this.results = results; w-~u[c
} \SB~rz"A
-w8c;5X
public String toString(){ jVh I`F{n
StringBuilder buff = new StringBuilder 8)(<U/
t- Rp_2t
(); 'G3;!xk$
buff.append("{"); a3o4> 9
buff.append("count:").append(count); We^!(G
buff.append(",p:").append(p); vj?v7
buff.append(",nump:").append(num); 1Ql\aO)
buff.append(",results:").append o+U]=q*|)$
j\V9o9D
(results); qEd!g,Sx
buff.append("}"); )ZkQWiP-
return buff.toString(); 9C-!I,
} Kv**(~FNnH
'%!'1si
} CuE>=y-"I
x)'4u6;d
[Tha
j