Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rshUF
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 LbR'nG{J
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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 EIPX q
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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 v
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分页支持类: ieXi6^M$
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java代码: Jw{duM;]
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package com.javaeye.common.util; gq="&
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import java.util.List; 6.6?Rp".
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publicclass PaginationSupport { B|'}HBkP
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publicfinalstaticint PAGESIZE = 30; wNmC1HOh
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privateint pageSize = PAGESIZE; #G=AD/z
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privateList items; [ B*r{
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privateint totalCount; uJ0Wb$%
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privateint[] indexes = newint[0]; flOXV
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privateint startIndex = 0; J5Ti@(G5V
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public PaginationSupport(List items, int %OP|%^2
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totalCount){ (B!DBnq
setPageSize(PAGESIZE); <-,y0Y'
setTotalCount(totalCount); '~1Zr uO
setItems(items); nC)"% Sa
setStartIndex(0); WuTkYiF
} L$y~\1-
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public PaginationSupport(List items, int W{~ y< `D
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totalCount, int startIndex){ t]?{"O1rC
setPageSize(PAGESIZE); ]bYmM@
setTotalCount(totalCount); g1(5QWb
setItems(items); ):y^g:
setStartIndex(startIndex); V/zmbo)
} *p9k> )'J
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public PaginationSupport(List items, int 0|8cSE<
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totalCount, int pageSize, int startIndex){ [a?bv7Kz
setPageSize(pageSize); A;o({9VH`Z
setTotalCount(totalCount); Ge^,hAM'
setItems(items); ^66OzT8A
setStartIndex(startIndex); =YD<q:n4
} ukRmjHbLf
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publicList getItems(){ E[4
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return items; *B9xL[}
} GK[9IF#_>
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publicvoid setItems(List items){ ixE w!t
this.items = items; rmr :G
} wSPmiJ/!
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publicint getPageSize(){ f.uy;v
return pageSize; O\)Kg2
} H({m1v ~R
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publicvoid setPageSize(int pageSize){ IreY8.FND
this.pageSize = pageSize; gyhy0
} G5 RdytK
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publicint getTotalCount(){ {7;QZk(
return totalCount; %5nEyZOq
} %~,Fe7#p
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publicvoid setTotalCount(int totalCount){ yO,Jgn
if(totalCount > 0){ i
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this.totalCount = totalCount; AlkHf]oB
int count = totalCount / N">#fYix
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pageSize; 'f.k'2T
if(totalCount % pageSize > 0) WWo"De@
count++; e,lLHg
indexes = newint[count]; ]E'?#z.t
for(int i = 0; i < count; i++){ !nlr!+(fV
indexes = pageSize * xEeHQ7J
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} .rnT'""i<5
}else{ rBy0hGx
this.totalCount = 0; 62y:i
} R0LWuE%eD
} 1&<o3)L:
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publicint[] getIndexes(){ MUGoW;}v)
return indexes; RDjw|V
} lnm@DWhf
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publicvoid setIndexes(int[] indexes){ J@}PySq
this.indexes = indexes; ^ meU&
} 96J]g*o(uU
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publicint getStartIndex(){ y`
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return startIndex; lyyf&?2
} \7pEn
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publicvoid setStartIndex(int startIndex){ -Dy<B
if(totalCount <= 0) o4Cq /K
this.startIndex = 0; WWH<s%C
elseif(startIndex >= totalCount) NffKK:HvBB
this.startIndex = indexes p<}y'7(
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[indexes.length - 1]; dUl"w`3
elseif(startIndex < 0) 'J5F+,\Ka
this.startIndex = 0; K2e*AE*
else{ wu`+KUx
this.startIndex = indexes U^% )BI
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[startIndex / pageSize]; X.[bgvm~C
} cMnN} '
} _ qwf3Q@
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publicint getNextIndex(){ *+2_!=4V
int nextIndex = getStartIndex() + @!O(%0
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pageSize; 8{ =ha
if(nextIndex >= totalCount) `~"'\Hw
return getStartIndex(); CQ^(/B^c
else <t*<SdAq>`
return nextIndex; Vsw:&$
} d_0(;'
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publicint getPreviousIndex(){ (
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int previousIndex = getStartIndex() - '}B"071)<
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pageSize; ~K99DK.
if(previousIndex < 0) 9c }qVf-i
return0; 4cM0f,nc+
else yNn=r;FZQ
return previousIndex; EltCtfm`
} ,d&3IhYhD
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} $`ptSR
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抽象业务类 Il(o[Q>jJ3
java代码: 96QY0
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/** W[
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* Created on 2005-7-12 &}7R\co3
*/ r
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package com.javaeye.common.business; B8n[ E
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import java.io.Serializable; 1_v\G
import java.util.List; _z{9V7n4
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import org.hibernate.Criteria; ITTEUw~+o
import org.hibernate.HibernateException; EG$-D@o\I
import org.hibernate.Session; (_>SuQK
import org.hibernate.criterion.DetachedCriteria; >/Q^.hzd
import org.hibernate.criterion.Projections; rKI<!
import c$L1aZo
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org.springframework.orm.hibernate3.HibernateCallback; z=g!mVK5
import #\n*Qg4p
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org.springframework.orm.hibernate3.support.HibernateDaoS wy${EY^h
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upport; L?N-uocT
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import com.javaeye.common.util.PaginationSupport; 92A9gY
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public abstract class AbstractManager extends <OKc?[
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HibernateDaoSupport { alHA&YC{K
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privateboolean cacheQueries = false; cSV&p|
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privateString queryCacheRegion; q >>1?hzA
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publicvoid setCacheQueries(boolean xP&7i'ag
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cacheQueries){ Fb8d=Zc
this.cacheQueries = cacheQueries; hhZ%{lqL
} <bSPKTKL
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publicvoid setQueryCacheRegion(String $,U/,XA
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queryCacheRegion){ SlR//h
this.queryCacheRegion = ZAN~TG<n
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queryCacheRegion; 7H{1i
} jG;J qT
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publicvoid save(finalObject entity){ EK"/4t{L_
getHibernateTemplate().save(entity); OW\vbWX
} 87+fd_G
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publicvoid persist(finalObject entity){ Y:,C_^$w;
getHibernateTemplate().save(entity); #Pf<2S
} <4vCx
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publicvoid update(finalObject entity){ ZCc23UwI
getHibernateTemplate().update(entity); 6Z J-oT!.
} 7kE+9HmfMk
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publicvoid delete(finalObject entity){ xRXvTNEg
getHibernateTemplate().delete(entity); m[3c,Axl7
} 83/m^^F{]
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publicObject load(finalClass entity, "B
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finalSerializable id){ 7]T(=gg /
return getHibernateTemplate().load ")i)vXF'
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(entity, id); >Jx=k"Kv+
} GF%/q :9
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publicObject get(finalClass entity, 'F.P93
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finalSerializable id){ `VO;\s$5j
return getHibernateTemplate().get n9={D
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(entity, id); YARL/V
} t^YtP3`?b
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publicList findAll(finalClass entity){ Jk&!(YK&
return getHibernateTemplate().find("from pY
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" + entity.getName()); K2xHXziQ
} : q%1Vi
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publicList findByNamedQuery(finalString np6G~0Y`
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namedQuery){ } f&=}
return getHibernateTemplate Zf!Q4a"
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().findByNamedQuery(namedQuery); Y]0c%Fd
} sV{\IgH/x
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publicList findByNamedQuery(finalString query, 59l9_yFJ
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finalObject parameter){ X coPkW
return getHibernateTemplate 2!B|w8ar
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().findByNamedQuery(query, parameter); &k}B66
} >(igVaZ>
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publicList findByNamedQuery(finalString query, U~7udUR
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finalObject[] parameters){ J.4U;A5
return getHibernateTemplate ]9/A=p?J@
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().findByNamedQuery(query, parameters); r.#r!.6 q
} r1%{\<
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publicList find(finalString query){ a"U3h[;$y
return getHibernateTemplate().find -sJD:G,%
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(query); E:**gvfq
} 8o%Vn'^t
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publicList find(finalString query, finalObject v8y Cf7+"
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parameter){ g&2g>]
return getHibernateTemplate().find L k
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(query, parameter); t}h(j|
} *aCVkFp
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public PaginationSupport findPageByCriteria [=jZP,b&),
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(final DetachedCriteria detachedCriteria){ eu$VKLY*
return findPageByCriteria 9 CZ@IFS
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); MjC<N[WO>N
} TCyev[(
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public PaginationSupport findPageByCriteria T2w4D!
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(final DetachedCriteria detachedCriteria, finalint )$E){(Aa
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startIndex){ wQy~5+LE
return findPageByCriteria ,%IP27bPW
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(detachedCriteria, PaginationSupport.PAGESIZE, g{}<ptx]
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startIndex); E<3xv;v8r
} `0]N#G
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public PaginationSupport findPageByCriteria hfY/)-60o
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(final DetachedCriteria detachedCriteria, finalint mq4Zy3H
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pageSize, U~ a\v8l~
finalint startIndex){ @Drl5C}+
return(PaginationSupport) SQK82/
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getHibernateTemplate().execute(new HibernateCallback(){ 06AgY0\
publicObject doInHibernate Pa d)|
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(Session session)throws HibernateException { 7 "'PfP4c
Criteria criteria = Posz|u<x
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detachedCriteria.getExecutableCriteria(session); -d4v:Jab
int totalCount = `H:`JBe=+[
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((Integer) criteria.setProjection(Projections.rowCount klQmo30i
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()).uniqueResult()).intValue(); dX1jn;7
criteria.setProjection >fP;H}S6
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(null); L1!~T+%uQ
List items = Ir>4- @
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criteria.setFirstResult(startIndex).setMaxResults bv]SR_Tiq
@,sjM]
(pageSize).list(); aB;f*x
PaginationSupport ps = s1cu5eCt
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new PaginationSupport(items, totalCount, pageSize, 3h.,7,T
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startIndex); y'^U4# (
return ps; DQW)^j
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} l([aKm#
}, true); D
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} W3UxFs]$
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public List findAllByCriteria(final =ZURh_{xV
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DetachedCriteria detachedCriteria){ k6(</uRj
return(List) getHibernateTemplate P2jh[a%
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().execute(new HibernateCallback(){ dI%jR&.e;
publicObject doInHibernate ZPE-
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(Session session)throws HibernateException { /YZMP'v
Criteria criteria = +zch e
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detachedCriteria.getExecutableCriteria(session); /Lr`Aka5
return criteria.list(); F!hjtIkPj
} #3_g8ni5X
}, true); 6:%lxG
} )ddJ\:
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public int getCountByCriteria(final yN`hW&K
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DetachedCriteria detachedCriteria){ 9kWI2cLzQt
Integer count = (Integer) )N- '~<N
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getHibernateTemplate().execute(new HibernateCallback(){ n;:.UGl9.
publicObject doInHibernate .+XK>jl+
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(Session session)throws HibernateException { deYv&=SPl
Criteria criteria = /# Jvt
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detachedCriteria.getExecutableCriteria(session); gd#R7[AVi
return +j F|8
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criteria.setProjection(Projections.rowCount ?q4`&";{3
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()).uniqueResult(); 0!YVRit\N
} Hl%Og$q3
}, true); fh)eL<I
return count.intValue(); ]s5e[iS
} R2~y<^.V`Y
} iP9]b&
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用户在web层构造查询条件detachedCriteria,和可选的 dpS@:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 tx[;& ;
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PaginationSupport的实例ps。 \,/ozfJ7dT
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ps.getItems()得到已分页好的结果集 '+$r7?dKP
ps.getIndexes()得到分页索引的数组 9c}C<s`M
ps.getTotalCount()得到总结果数 E<-W & a }
ps.getStartIndex()当前分页索引 =/'>.p3/S
ps.getNextIndex()下一页索引 v7@"9Uw}
ps.getPreviousIndex()上一页索引 ] H;E(1iU
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 rz|Sjtq
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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 PtUS7[]
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一下代码重构了。 $H3C/|
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我把原本我的做法也提供出来供大家讨论吧: DI;LhS*z
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首先,为了实现分页查询,我封装了一个Page类: $~:ZzZO
java代码: cu5}(
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/*Created on 2005-4-14*/ :,p3&2I
package org.flyware.util.page; 3v3cK1K@oE
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/** j^b&Q
* @author Joa L T`T~|pz
* 9HN&M*}
*/ :tFcPc'
publicclass Page { yO8@ .-j b
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/** imply if the page has previous page */ ]6v7iuvI
privateboolean hasPrePage; xv$fw>
@(=?x:j
/** imply if the page has next page */
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privateboolean hasNextPage; 3`SH-"{j%
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/** the number of every page */ )ZLj2H <
privateint everyPage; g$ )0E<
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/** the total page number */ &,p6lbP
privateint totalPage; K($+ILZ
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/** the number of current page */ C<:wSS^@1
privateint currentPage; 0# 1~'e
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/** the begin index of the records by the current ^=-25%&^
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query */ h){ #dU+&
privateint beginIndex; @/As|)
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/** The default constructor */ |uFb(kL[U
public Page(){ |I"&Z+m
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} Su,<idS
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/** construct the page by everyPage bSI*`Dc"!
* @param everyPage G
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* */ t`}=~/#`X
public Page(int everyPage){ !7]^QdBLY
this.everyPage = everyPage; ixM#|Yq
} gP8}d*W%b
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/** The whole constructor */ \[]BB5)8
public Page(boolean hasPrePage, boolean hasNextPage, jsV1~1:83
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int everyPage, int totalPage, lv.h?"Ml
int currentPage, int beginIndex){ 15|gG<-
this.hasPrePage = hasPrePage; "3 2Ua3m:G
this.hasNextPage = hasNextPage; KTo}xLT
this.everyPage = everyPage; H<^3H
this.totalPage = totalPage; Zg= {
this.currentPage = currentPage; Yqu/_6wLx
this.beginIndex = beginIndex; ]x& R=)P
} \mb@-kM)
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/** j}@LiH'Q
* @return qa:muW
* Returns the beginIndex. Ygfy;G%
*/ a&mL Dh/
publicint getBeginIndex(){ [UdJ(cGf
return beginIndex; k+@ :+RL
} g:c?%J
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/** 4yMi9Ri4H
* @param beginIndex 5``usn/&Kj
* The beginIndex to set. 5K|`RzZ`B$
*/ 5D^2
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publicvoid setBeginIndex(int beginIndex){ gHL:XW^
this.beginIndex = beginIndex; (i<\n`h1K
} ZLP0SCkuR
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/** 2I=4l
* @return )h(=X&(d
* Returns the currentPage. 8-L -W[
*/ /^si(BuC^*
publicint getCurrentPage(){ 0yUn~'+(Sp
return currentPage; 2B6y1" B
} >"zN`
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/** V2m=
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* @param currentPage .)t*!$5=N
* The currentPage to set. nGJ+.z
*/ U;
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publicvoid setCurrentPage(int currentPage){ 33"!K>wC
this.currentPage = currentPage; =ZV+*cCC=q
} 0eA|Uq~
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/** qssK0!-
* @return se _Oi$VZ{
* Returns the everyPage. uqBV KE
*/ T%PUV \LV
publicint getEveryPage(){ HXB&
6
return everyPage; nob}}w]~C
} {*F8'6YQ$
>#;>6q9_
/** &]KA%Db2
* @param everyPage ~^3U@(:
* The everyPage to set. BQgK<_
*/ M;.:YkrUH
publicvoid setEveryPage(int everyPage){ \%W"KLP
this.everyPage = everyPage; 0o@eE3^
} %NhZTmWm
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/** 6D4u?P,
* @return -OgC. 6
* Returns the hasNextPage. ?O#"x{Pk
*/ Jd|E
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publicboolean getHasNextPage(){ <5|:QLqy
return hasNextPage; '_n$xfH
} 0e'@Xo2e
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/** ;T!ZO@1X
* @param hasNextPage Z7MGBwP(
* The hasNextPage to set. 99Nm? $g
*/ `qy@Qo
publicvoid setHasNextPage(boolean hasNextPage){ Q,o"[ &Gp
this.hasNextPage = hasNextPage; f Lns^
} UtB~joaR
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/** ir;az{T#U
* @return s<LYSr d
* Returns the hasPrePage. NF*Z<$ '%
*/ .Ax]SNZ+:A
publicboolean getHasPrePage(){ FCt %of#
return hasPrePage; EHq?yj;
} >\1j`/ :ZI
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/** 7t%
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* @param hasPrePage U,\t2z
* The hasPrePage to set. |198A,^
*/ ZlL]AD@
publicvoid setHasPrePage(boolean hasPrePage){ F^wm&:%{`
this.hasPrePage = hasPrePage; D'_w
*
} 7}fT7tsN
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/** ? C6tYd
* @return Returns the totalPage. *b(nX,e
* HhqNpU
*/ to] ~$~Q|>
publicint getTotalPage(){ }}d,xI
return totalPage; WSx0o}
} { =IAS}
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/** ]6?6 k4@
* @param totalPage @t#Ju1Y
* The totalPage to set. jH2_Ekgc;_
*/ Cl!qdh6
publicvoid setTotalPage(int totalPage){ oMb@)7
this.totalPage = totalPage; kfs[*ku
} Uj)`(}r
zhC5%R &n/
} SGLU7*sfd
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 2?(dS
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个PageUtil,负责对Page对象进行构造: {} Zqaf
java代码: ;v%f +
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/*Created on 2005-4-14*/ r[KX"U-
package org.flyware.util.page; a~Y`N73/c
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import org.apache.commons.logging.Log; lemUUl(^
import org.apache.commons.logging.LogFactory; t$ 3/ZTx
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/** Ou2p^:C(
* @author Joa 6fw2;$x"
* F+m;y
*/ -h,?_d>
publicclass PageUtil { M_f.e!?
@@#h-k%k-
privatestaticfinal Log logger = LogFactory.getLog 6{?B`gm7g
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(PageUtil.class); l[b`4
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/** q3/ 0xN+?
* Use the origin page to create a new page Xny{8Oo<1?
* @param page '>#8
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* @param totalRecords tE;c>=>t
* @return lw_PQ4Hp
*/ qPgny/(
publicstatic Page createPage(Page page, int 1HBXD\!
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totalRecords){ Nu7lPEM
return createPage(page.getEveryPage(), %"BJW
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page.getCurrentPage(), totalRecords); }\aJ%9X02
} <,Pk
.%+y_.l
/** Q?{^8?7
* the basic page utils not including exception &O^t]7
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handler }]|e0 w:
* @param everyPage 5T]dQ3[v4
* @param currentPage _.^`DP>
* @param totalRecords IOOK[g.?h
* @return page T8>aU
*/ rE9Nt9}
publicstatic Page createPage(int everyPage, int S0!w]Ku
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currentPage, int totalRecords){ p?'&P!
everyPage = getEveryPage(everyPage); x5eSPF1
currentPage = getCurrentPage(currentPage); 9}aEV 0 V|
int beginIndex = getBeginIndex(everyPage, Q4F&#^02y
w7QYWf'
currentPage); o!W(
int totalPage = getTotalPage(everyPage, E{{Kzr2$
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totalRecords); =&roL7ps
boolean hasNextPage = hasNextPage(currentPage, ibh,d.*~g
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totalPage); jAy0k
boolean hasPrePage = hasPrePage(currentPage); X
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returnnew Page(hasPrePage, hasNextPage, ZFRKzPc
{V
everyPage, totalPage, 80 ckh
currentPage, OzAxnd\.N
5N:IH@
beginIndex); $Ahe Vps@@
} G]O5irsV
V$3`y=8
privatestaticint getEveryPage(int everyPage){ w
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return everyPage == 0 ? 10 : everyPage; q0VR&b`?>D
} QfRo`l/V9
c[a^fu!
privatestaticint getCurrentPage(int currentPage){ uFn?U)
return currentPage == 0 ? 1 : currentPage; /^=8?wK
} Nf)$K'/
PUErvLt
privatestaticint getBeginIndex(int everyPage, int /-Z}=
'>[Ut@lT;
currentPage){ arN=OB
return(currentPage - 1) * everyPage; % !Ih=DZ
} w[OUGn'
@z>DJ>htN
privatestaticint getTotalPage(int everyPage, int #O^%u,mJj
t:*1*;
totalRecords){ -mLS\TF S
int totalPage = 0;
>Ft)v
5Kw?#
if(totalRecords % everyPage == 0) i7%`}t
totalPage = totalRecords / everyPage; B0D
else jGe%'AN\
totalPage = totalRecords / everyPage + 1 ; T}59m;I
"w3%BbI x
return totalPage; ]EqwDw4
} ji.T7wn1u
5:(/k\9+yv
privatestaticboolean hasPrePage(int currentPage){ "<&) G{
return currentPage == 1 ? false : true; DcN!u6sJ
} ~]SCf@pRk
63/a 0Yn
privatestaticboolean hasNextPage(int currentPage,
@W-0ybv
C%H?vrR
int totalPage){ afE)yu`
return currentPage == totalPage || totalPage == $N\k*=
lN*beOj
0 ? false : true; 7QRkXs
} \&[(PNl
ic}mru
L}rYh`bUP[
} 0X5b32
K
#}t\
h 27f0x9
^0 &jy:{
iP6?[pl8
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 NuW6~PV
hR~&}sxN
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 d'iSvd.
D7=Irz!O\7
做法如下: Z"$iB-]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 T"1=/r$Ft
X.ecA`0
的信息,和一个结果集List: [,(+r7aB
java代码: }m&\I
S_?sJwM
Po*!eD
/*Created on 2005-6-13*/ & H8 %
package com.adt.bo; 3n~O&{
qiH)J-
~GZ
import java.util.List; m|3Q'
88l1g,`**
import org.flyware.util.page.Page; u;+8Jg+xH/
KW$.Yy
/** _|T{2LvwT
* @author Joa \i+Ad@)
*/ *Qyu
QF
publicclass Result { &4ndi=.#rg
(I/iD.A
private Page page; ]-_ ma
"z*.Bk
private List content; ?TJ4L/"(k6
sDAP'&
/** Xk\IO0GF
* The default constructor uh`5:V
*/ Swh\^/B8
public Result(){ cbl>:ev1h
super(); _D$1CaAYo
} +;4;~>Y
QAAuFZs
/** e+)y6Q=
* The constructor using fields hu.p;A3p;
* g#`}HuPoE
* @param page e4|a^lS;
* @param content c-_1tSh}
*/ R+z'6&/ =I
public Result(Page page, List content){ Kp^"<%RT
this.page = page; 5h |aX
this.content = content; ix$
^1(
} >'4$g7o,
B):ZX#
/** LcB+L](
* @return Returns the content. -xbs'[
*/ cQ'x]u_
publicList getContent(){ Y% JE})
return content; %|D)U>o{
} -}PE(c1%?q
#RbdQH !
/** mG$N%`aG
* @return Returns the page. .)=*Yr M
*/ 9yaTDxB>
public Page getPage(){ TQb@szp:|
return page; rIb~@cR)
} @,7r<6E
P_'{|M<?
/** -v-kFzu
* @param content ![$`Ivro`
* The content to set. [+QyKyhTO
*/ `wZ
public void setContent(List content){ Hpa6;eT
this.content = content; H\H7a.@nkF
} bRrSd:e
k`&FyN^)
/** Z=Cw7E
* @param page w>8kBQ?b
* The page to set. &-{%G=5~e%
*/ kvuRT`/
publicvoid setPage(Page page){ 6212*Z_Af
this.page = page; 'n>44_7 L
} %hN(79:g
} ]uF7HX7F
E_I-.o|
pJs`/
vq.o;q /
$STGH
2. 编写业务逻辑接口,并实现它(UserManager, cJbv,RV<
tQRbNY#}Z
UserManagerImpl) GyMN;|
java代码: /W`CqJk-*.
i /I
]*'_a@h
/*Created on 2005-7-15*/ lNf );!}SM
package com.adt.service; o5 ~VT!'[
U<;{_!]
import net.sf.hibernate.HibernateException; bq)1'beW
S7WHOr9XMV
import org.flyware.util.page.Page; ^*4#ZvpG2
6"Lyv
import com.adt.bo.Result; Q)BSngW+
bcjh3WP
/** n1GX`K
* @author Joa Dt> tTU 6
*/ 65JG#^)KaX
publicinterface UserManager { *0Z6H-Do,
1*G&ZI
public Result listUser(Page page)throws f0Q! lMv
AZE%fOG<i
HibernateException; )Ute
kr|r-N`
} ;?@Rq"*
8(l0\R,%+z
5'+g[eNyBV
g!'
x5#]n
y9]7LETv\M
java代码: |bSAn*6b
{D^
)%{
ULu@"
/*Created on 2005-7-15*/ ,/GFD[SQ
package com.adt.service.impl; 5Za<]qxr
>yLDU_P)
import java.util.List; rir,|y,
$xdo=4;|
import net.sf.hibernate.HibernateException; d*e8P ep
qdwo 2u
import org.flyware.util.page.Page; EtPB_!
+
import org.flyware.util.page.PageUtil; /Dd x[P5p=
eY`9J4o '
import com.adt.bo.Result; 37:tu7e~c
import com.adt.dao.UserDAO; |v@_~HV
import com.adt.exception.ObjectNotFoundException; Og1\6Q
import com.adt.service.UserManager; ?Fa$lE4
Rf8ZH
/** IKnf
* @author Joa X_nbNql
*/ Oi& 9FS
publicclass UserManagerImpl implements UserManager { Sin)]zG~0
HJJ)D E7;
private UserDAO userDAO; G~.VW48{n
x=a#|]ngG
/** ^GrSvl}v'
* @param userDAO The userDAO to set. K$D+TI)
*/ [h-NX
publicvoid setUserDAO(UserDAO userDAO){ E#Ue9J
this.userDAO = userDAO; 1|-C(UW>
} fKFD>u0%
17c`c.yP
/* (non-Javadoc) ujE~#b}X
* @see com.adt.service.UserManager#listUser sx;/xIU|
|oSt%lQ1
(org.flyware.util.page.Page) A{B$$7%
*/ e 2NF.
public Result listUser(Page page)throws /6[vF)&
+h/OQ]`/m
HibernateException, ObjectNotFoundException { Ksh[I,+N\
int totalRecords = userDAO.getUserCount(); tj00xYY
if(totalRecords == 0) H|aC(c
throw new ObjectNotFoundException (zy|>u
G7,v:dlK
("userNotExist"); 7b-[# g
page = PageUtil.createPage(page, totalRecords); 9Z=hg[`]<
List users = userDAO.getUserByPage(page); kSol%C
returnnew Result(page, users); ? eI)m
} N4-Y0BO
.Wp(@l'Hd
} dc~vQDNw[X
K%BFR,)g
^/Yk*Ny
:N^B54o%6
-{JReplc
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K iXD1Zpz
_C1u}1hW#
询,接下来编写UserDAO的代码: ]Hi1^Y<
3. UserDAO 和 UserDAOImpl: Q2]7|C
java代码: "30=!k
U
v>^ Z2
!@Vj&>mH$
/*Created on 2005-7-15*/ w^HI
lA
package com.adt.dao; bOrE86v:
bT9:9LP
import java.util.List; rO#$SW$YW
JUDZ_cGr
import org.flyware.util.page.Page; j!Ys/D
9"1=um=
import net.sf.hibernate.HibernateException;
#z.\pd
#=Xa(<t
/** ujX\^c
* @author Joa 2++$ Ql/
*/ >dF #1
publicinterface UserDAO extends BaseDAO { { i3x\|
<b\.d^=B
publicList getUserByName(String name)throws GpO@1 C/
!f/^1k}SR
HibernateException; L:lnm9<
m |+zMf&
publicint getUserCount()throws HibernateException; b+ZaZ\-y
|
iK'A m.o+
publicList getUserByPage(Page page)throws 9S'\&mRl
#&S<{75A
HibernateException; B}p.fE
"].TKF#yg
} yfFe%8w_vw
.1J`>T?=Q
[tt_>O
S*3$1BTl
>B;S;_5=
java代码: q4"^G:
R~TG5^(
ko!aX;K
/*Created on 2005-7-15*/ ^H<VH
package com.adt.dao.impl; A"+t[0$.
(lit^v,9
import java.util.List; )F'hn+(B|G
7A<}JaE!,
import org.flyware.util.page.Page; c-@EHv
pAN$c"
import net.sf.hibernate.HibernateException; I]m&h!
import net.sf.hibernate.Query; /dX,]OFm
Ja\B%f
import com.adt.dao.UserDAO; vl%Pg!l
7#*O|t/'
/** aM8z_j!!u
* @author Joa /~<Przw
*/ 5KYR"-jY
public class UserDAOImpl extends BaseDAOHibernateImpl u<j.XPK
}zeKf/?'
implements UserDAO { Xa>c]j
RhjU^,%
/* (non-Javadoc) X)9|ZF2`
* @see com.adt.dao.UserDAO#getUserByName o+<hI
2V+[:>F
(java.lang.String) <sGioMr
*/ >6;RTN/P2
publicList getUserByName(String name)throws cetlr
JvW!w)$pY
HibernateException { ,Qe`(vU*s
String querySentence = "FROM user in class :KRe==/
63i&e/pv
com.adt.po.User WHERE user.name=:name"; dUceZmAl
Query query = getSession().createQuery
DshRH>7s8
E@="n<uS
(querySentence); FEA/}*2F
query.setParameter("name", name); <@@@Pl!~
return query.list(); +w@/$datI
} .M\0+,%/
,(#n8|q4
/* (non-Javadoc) )7rMevF(xJ
* @see com.adt.dao.UserDAO#getUserCount() VN@ZYSs
*/ R*O6Z"h
publicint getUserCount()throws HibernateException { T5 BoOVgO
int count = 0; VK4"
String querySentence = "SELECT count(*) FROM % o0.8qVJi
=OA7$z[
user in class com.adt.po.User"; OPKmYzf@b
Query query = getSession().createQuery 1
7hXg"B
0L7^Vr)
(querySentence); G{|FV
m
count = ((Integer)query.iterate().next jB d9
$`
:4238J8
()).intValue(); ."v&?o
Ck]
return count; ou&7v<)x4
} n ZS*"O#L
gi\UNT9x
/* (non-Javadoc) qSL~A-
* @see com.adt.dao.UserDAO#getUserByPage 2 BwpxV8
v|>'m#Ln2
(org.flyware.util.page.Page) !r0 z3^*N
*/ /lvH p
publicList getUserByPage(Page page)throws UC9w T
HR k^KB
HibernateException { VoUAFEcs
String querySentence = "FROM user in class C?b_E
g\,HiKBXd
com.adt.po.User"; \3z ^/F~
Query query = getSession().createQuery ( e(<4-&
%G~%:uJ5
(querySentence); =CO#Q$
query.setFirstResult(page.getBeginIndex()) "[]72PC
.setMaxResults(page.getEveryPage()); af7\2g3*
return query.list(); TWQ{,
B
} >E(IkpZ
*W<g%j-a
} tZY(r
{
UBy:W^\g
8c'E
SbpO<8}8
Ibl==Irk
至此,一个完整的分页程序完成。前台的只需要调用 j6$_U@)%O
!Lj+&D|z
userManager.listUser(page)即可得到一个Page对象和结果集对象 K<tkNWasQ
8DNGqaH;dt
的综合体,而传入的参数page对象则可以由前台传入,如果用 "PPn^{bYm
~ +z'pK~c
webwork,甚至可以直接在配置文件中指定。 I#hzU8Cc
;tLu
下面给出一个webwork调用示例: {mV,bg,}~
java代码: *YY:JLe
-n$fh::^
r`/tb^
/*Created on 2005-6-17*/ xo_Es?
package com.adt.action.user; %!1:BQ,p,i
+EgQj*F*
import java.util.List; !~k-Sexh
<%rG*vzi
import org.apache.commons.logging.Log; ^k?Ig.m
import org.apache.commons.logging.LogFactory; =2[cpF]
import org.flyware.util.page.Page; >U$,/_uMNW
F D6>[W
import com.adt.bo.Result; r&ex<(I{
import com.adt.service.UserService; "%Eyb\V!
import com.opensymphony.xwork.Action; /ZKO\q
~A=Z/46*Z
/** 8>K2[cPD
* @author Joa f8
M=P.jz
*/ l*yJU3PW
publicclass ListUser implementsAction{ L$FLQyDR
A5gdZZ'x
privatestaticfinal Log logger = LogFactory.getLog C"ZCX6p+$
eq\{*r"DCK
(ListUser.class); &wZ:$lK#o
p,9eZUGy
private UserService userService; G l*C"V
<%Re!y@OL
private Page page; TNV#
Si]8*>}-B
privateList users; Fu (I<o+T-
asI:J/%+2
/* u37@9
* (non-Javadoc) =jmn
* ghiFI<)VY
* @see com.opensymphony.xwork.Action#execute() wLC|mByq
*/ A`Bg"k:D
publicString execute()throwsException{ .HG0%Vp
Result result = userService.listUser(page); @[S\ FjI
page = result.getPage(); c;bp[Y3R
users = result.getContent(); dDy9yw%f?
return SUCCESS; _,;c2
} !W8'apG&[
Aj4i}pT
/** &`63"^y
* @return Returns the page. {E`f(9r:
*/ A:ef}OCL
public Page getPage(){ '5eW"HGU]`
return page; -U=bC
} "Gxf[6B
}o?@
/** M(S:&GOU
* @return Returns the users. ]#[R^t
*/ 6?ylSQ]1
publicList getUsers(){ m`-{ V<(M
return users; d7tH~9GX8
} c X553&
b07 MTDFH7
/** i3>7R'q>
* @param page qGgT<Rd~1
* The page to set. Zcv1%hI
*/ )fR'1_
publicvoid setPage(Page page){ o% !a
this.page = page; c0jC84*v
} 1NT@}j~/
z/N~HSh!d
/** Ut8yA"Y~
* @param users ?E2/
CM
* The users to set. [HK[{M=v=
*/ dGcG7*EX
publicvoid setUsers(List users){ (6fh[eK86
this.users = users; -pc*$oe
} BxO8oKe
7WW@%4(
/** ~ FM5]<X)
* @param userService K9gfS V>]
* The userService to set. #tdI;x3
*/ Hc4]2pf
publicvoid setUserService(UserService userService){ cyG3le& +G
this.userService = userService; Qg9 N?e{z
} }0|,*BkI
m
} 5B@+$D[0?3
4 ?,N;Q
+=^10D
'cT R<LVo
3ePG=^K^
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ' Ky5|4
PSNrY e
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 hO@'WoniW
_bn*B$
么只需要: p^A9iieHp=
java代码: Ylll4w62N
BYrj#n5
Y_)!U`>N?
<?xml version="1.0"?> c:4M|t=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork *K'(t
soXeHjNl
1.0//EN" "http://www.opensymphony.com/xwork/xwork- x\GCsVy
)avli@W-3j
1.0.dtd"> InMF$pw
sV'(y>PP%
<xwork> X4lz?Y:*
z'JtH^^Z
<package name="user" extends="webwork- kA{[k
$+)SW{7
interceptors"> [F/>pL5U$
;zIAh[z
<!-- The default interceptor stack name u)MdFz
vu;pILN
--> -S
OP8G
<default-interceptor-ref hkee,PiiP
?A;x%8}
name="myDefaultWebStack"/> ksT2_Ic
1p<m>s=D=e
<action name="listUser" Tz]t.]!&E
hdp;/Qz&
class="com.adt.action.user.ListUser"> S.aSNH<
<param 3@*J=LGhKc
KQj5o>} 6
name="page.everyPage">10</param> fn(KmuNA
<result |[;9$Vn
0p:FAvvNI
name="success">/user/user_list.jsp</result> Ua)ARi %
</action> pM=@
<V#9a83JP
</package> ds,NNN<HW
_<|NVweFS
</xwork> 0{j]p^'<
htj:Z:C`
hMh8)S
<T+)~&g$
YN#i^(
/mX/
"~
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 L]3 V)`}
>fJY
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。 +Fp8cT=1
nxkbI:+t
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 p?2\9C4
U6e 0{n
:[|4Zn
{M96jjiInf
u+a"
'*
我写的一个用于分页的类,用了泛型了,hoho N?TXPY
K>hQls+
java代码: //n$#c_}u
9q5jqFQ
_SC{nZ[
package com.intokr.util; )HQ':ZE$
-'r4@='6}
import java.util.List; :3J,t//c
V6P2W0m
/** _o/LFLq
* 用于分页的类<br> xr}3vJ7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?zGx]?1P1<
* iqm]sC`
* @version 0.01 VPoA,;Y"-
* @author cheng uT:'Kkb!
*/ :jlKj} 4A
public class Paginator<E> { 3oc p4x`[
privateint count = 0; // 总记录数 E1 IT>_
privateint p = 1; // 页编号 Fcz7
privateint num = 20; // 每页的记录数 jR[VPm=
privateList<E> results = null; // 结果 lZ|+.T!g?
lKWe=xY\B
/** u0 myB/`
* 结果总数 9+H C!Uot
*/ 2CcUClP$
publicint getCount(){ gb+iy$o-
return count; =jXBF.
} jYDpJ##Zb
m:&go2Y
publicvoid setCount(int count){ h|qTMwPr
this.count = count; BdBwfH%:
} @yp#k>
Cw6\'p%l-\
/** 0M=A,`qk
* 本结果所在的页码,从1开始 ybNo`:8A;
* Yuo:hF\DH
* @return Returns the pageNo. M3 MB{cA2
*/ Iv])s
publicint getP(){ 1T&NU
return p; )`
~"o*M
} {Tx"G9
U;
-2)+
/** !\|_,pSB
* if(p<=0) p=1 >NLG"[\
* rlxZ,]ul
* @param p w5fVug/;P
*/ hOFC8 g
publicvoid setP(int p){ O0^m_
if(p <= 0) )Y4;@pEU
p = 1; W]Bc7JM]T+
this.p = p; #gW"k;7P
} HiAj3
7PTw'+{
/** nv$>iJ^~H
* 每页记录数量 6Qtyv
*/ jW]Q-
publicint getNum(){ BoJpf8e'-e
return num; bu0i#
} zF:
:?L~
M%&1j >d
/** +;r1AR1)x
* if(num<1) num=1 0?V{u`*
*/ 0zQ~'x
publicvoid setNum(int num){ mIW8K
):
if(num < 1) 75v7w
num = 1; N+lhztYQ?
this.num = num; DVJuX~'|!
} gq%U5J"x;J
?D>%+rK8c
/** `JQw]\f4>
* 获得总页数 >EE}P|=-
*/ M./1.k&@
publicint getPageNum(){ /{6&99SJcc
return(count - 1) / num + 1; &t)$5\r
} l,fwF ua
&{4KymB:
/** >]{{5oOQ>
* 获得本页的开始编号,为 (p-1)*num+1 {L'uuG\9U
*/ 3~q#P
publicint getStart(){ B*Z}=$1j
return(p - 1) * num + 1; osM[Xv
} uNKf!\Y
J497
>w[
/** hMCf|
e.UY
* @return Returns the results. #W$6[#7=I
*/ tt4Z
publicList<E> getResults(){ gQQve{'
return results; `.i #3P
} (N"9C+S}
L;\f^v(
public void setResults(List<E> results){ QLxe1[qI
this.results = results; U8S<wf&
} t
$m:
`}:pUf
public String toString(){ -6W$@,K
StringBuilder buff = new StringBuilder P(oGNKAS
[L>mrHqG
(); r\A|fiL
buff.append("{"); ppuJC'GW
buff.append("count:").append(count); Y sDai<
buff.append(",p:").append(p); %y)]Q|
buff.append(",nump:").append(num); sWyx_
buff.append(",results:").append GvzaLEo
B/Js>R
(results); 7Y?59
[
buff.append("}"); _U|rTil
return buff.toString(); kfY. 9$(d
} xLdkeuL[%
%MCJ%Ph
} &8;Fi2}(L
f4O}WU}l{s
g-pEt#