Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 iNG =x
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =j^wa')
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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 `-yiVUp1:z
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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 eQ80Kf~
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分页支持类: n,*E
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java代码: z *~rd2
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package com.javaeye.common.util; aBT8mK -.
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import java.util.List; !~!\=etm
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publicclass PaginationSupport { r[4dGt
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publicfinalstaticint PAGESIZE = 30; -}KW"#9c
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privateint pageSize = PAGESIZE; >fx/TSql:J
9HG" }CGZP
privateList items; iL;{]A'0
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privateint totalCount; !HSX:qAP$
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privateint[] indexes = newint[0]; d'!abnF[d
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privateint startIndex = 0; K?gO]T{6
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public PaginationSupport(List items, int ,%$Cfu
yq,%<%+
totalCount){ CooOBk
setPageSize(PAGESIZE); Ie'iAY
setTotalCount(totalCount); NzC&ctPk
setItems(items); <~P([5
setStartIndex(0); OJ,Z
} H':0
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public PaginationSupport(List items, int T~)zgu%q_
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totalCount, int startIndex){ n*y@3.
setPageSize(PAGESIZE); ]6;oS-4gu?
setTotalCount(totalCount); (&xIBF_6
setItems(items); {IT;g9x
setStartIndex(startIndex); by*v($
} /9(8ML#E
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public PaginationSupport(List items, int v\Edf;(
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totalCount, int pageSize, int startIndex){ j\TS:F^z
setPageSize(pageSize); Rkh
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setTotalCount(totalCount); 2X|nPhNi
setItems(items); _v +At;Y
setStartIndex(startIndex); w02t9vz
} 7!('+x(>
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publicList getItems(){ A}z1~Z+
return items; 28=L9q
} <: I]0|[
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publicvoid setItems(List items){ a 8.Xy])!
this.items = items; u%rB]a$/
} Vho^a:Z9}W
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publicint getPageSize(){ xT;j_'9U;
return pageSize; ^5~)m6=2
}
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publicvoid setPageSize(int pageSize){ "MU)8$d
this.pageSize = pageSize; H'wh0K(
} VIg=|Oe),
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publicint getTotalCount(){ 6uubkt
return totalCount; H`Ld,E2ex&
} ]_&pIBp
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publicvoid setTotalCount(int totalCount){ KSy.
if(totalCount > 0){ Eumdv#Qg
this.totalCount = totalCount; 5H
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int count = totalCount / 9Li.B1j
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pageSize; WDQw)EUl&
if(totalCount % pageSize > 0) iBPx97a
count++; dxF/]>t
indexes = newint[count]; I<L<xwh1(E
for(int i = 0; i < count; i++){ uc-Go
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indexes = pageSize * n9r3CLb[
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i; "U%jG`q
} 7T@"2WYat
}else{ ~AG."<}
this.totalCount = 0; u@$pOLI
} )0xEI
} aIABx!83>
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publicint[] getIndexes(){ .47tj`L
return indexes; 4Q
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} %QKRl5RM-
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publicvoid setIndexes(int[] indexes){ jj*e.t:F
this.indexes = indexes; 7COJ.rA
} Mv^G%zg2
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publicint getStartIndex(){ ?UV^6
return startIndex; J t,7S4JL
} rCFTch"
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publicvoid setStartIndex(int startIndex){ ?L~Z]+-
if(totalCount <= 0) 1q(o3%
this.startIndex = 0; y6!Zt}m
elseif(startIndex >= totalCount)
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this.startIndex = indexes d*TpHLm
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[indexes.length - 1]; +i.b&PF'H
elseif(startIndex < 0) >!|(n@
this.startIndex = 0; Hxzdxwz%$
else{ hg=BXe4:
this.startIndex = indexes 1O]27"9
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[startIndex / pageSize]; Je~d/,^WU
} ~ E|L4E
} MX#MDA-4
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o;
publicint getNextIndex(){ *^5..0du
int nextIndex = getStartIndex() + %Jc>joU
x#s=eeP1
pageSize; VIjsz42C
if(nextIndex >= totalCount) 58 Rmq/6s
return getStartIndex(); W9ewj:4\0
else ,"!P{c
return nextIndex; 6X.lncE@p
} !rMl" Y[
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publicint getPreviousIndex(){ ^>f jURR
int previousIndex = getStartIndex() - 7,N>u8cTh
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pageSize; hf1f
if(previousIndex < 0) c(<,qWH
return0; `X7ns?
else >@o}l:*
return previousIndex; \PB ~6
} 044*@a5f
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} zu
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抽象业务类
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java代码: p8q9:Tz
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/** fYzOT,c
* Created on 2005-7-12 yEfV8aY'*
*/ |,ZmRW^2K
package com.javaeye.common.business; {m/\AG)1I
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import java.io.Serializable; D~xUr)E
import java.util.List; *QF3l0&
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import org.hibernate.Criteria; G/Xa`4"_
import org.hibernate.HibernateException; \
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import org.hibernate.Session; %#Vn?zr|~
import org.hibernate.criterion.DetachedCriteria; Zbp ByRyN
import org.hibernate.criterion.Projections; !m#cneV
import 'sL>U$(
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org.springframework.orm.hibernate3.HibernateCallback; wO y1i/oj
import $3!j1
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org.springframework.orm.hibernate3.support.HibernateDaoS ul e]eRAG
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upport; Ha\q}~_
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import com.javaeye.common.util.PaginationSupport; lq$1CI
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public abstract class AbstractManager extends O\T
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HibernateDaoSupport { $+<X 1
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privateboolean cacheQueries = false; +_?;%PKkuF
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privateString queryCacheRegion; N2VF_[l
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publicvoid setCacheQueries(boolean <)zh2UI
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cacheQueries){ EO,;^RtB
this.cacheQueries = cacheQueries; A`7uw|uO$
} 'r%`(Z{~
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publicvoid setQueryCacheRegion(String QY2!.a^q
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queryCacheRegion){ $.}fL;BzVz
this.queryCacheRegion = ih?_ fW
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queryCacheRegion; !+.|T9P
} w.cQ|_
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publicvoid save(finalObject entity){ }}?L'Vby
getHibernateTemplate().save(entity); A>$VkGo
} i_ 4FxC4
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publicvoid persist(finalObject entity){ }(-R`.e;
getHibernateTemplate().save(entity); ^\cB&<h
} ke~O+]
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publicvoid update(finalObject entity){ \qAMs^1-
getHibernateTemplate().update(entity); y'Xg"
} +7o3TA]-
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publicvoid delete(finalObject entity){ 8^zI
getHibernateTemplate().delete(entity); +|Q8P?YD_
} /40Z-'Bl=(
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publicObject load(finalClass entity, A0M)*9 f
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finalSerializable id){ o:#MP(h,N
return getHibernateTemplate().load zp4Jd"XBX
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(entity, id); {so"xoA^c
} @4h .?
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publicObject get(finalClass entity, m4ovppC
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@
finalSerializable id){ KEsMes(*
return getHibernateTemplate().get ~,Q+E8
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(entity, id); C$)#s{*
} pq>"GEN
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publicList findAll(finalClass entity){ -zHJ#
return getHibernateTemplate().find("from PF@<>NO+W
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" + entity.getName()); l{aXX[E&1
} ;,Sl+)@h
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publicList findByNamedQuery(finalString (I, PC*:
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namedQuery){ 8;.WX
return getHibernateTemplate R3&W.?C
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().findByNamedQuery(namedQuery); T eG5|`t],
} 6{}]QvR
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publicList findByNamedQuery(finalString query, LKxyj@Eq
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finalObject parameter){ s9qr;}U.`
return getHibernateTemplate j;1X-
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().findByNamedQuery(query, parameter); Az6f I*yP
} _7]* 5Pxo
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publicList findByNamedQuery(finalString query, WU{G_Fqaz
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finalObject[] parameters){ s{KwO+ UW
return getHibernateTemplate I8`@Srw8
#=5/D@
().findByNamedQuery(query, parameters); MaXgy|yB1
} Yc /rjEn7O
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publicList find(finalString query){ }!(cm;XA"
return getHibernateTemplate().find =cM\o{ q
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(query); ?W9$=
} 3F[z]B
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publicList find(finalString query, finalObject 4{X5ZS?CkI
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parameter){ :Y0*P
return getHibernateTemplate().find U=QV^I Qm
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(query, parameter); F.?^ko9d
} gx#xB8n
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public PaginationSupport findPageByCriteria 41^+T<+
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(final DetachedCriteria detachedCriteria){ ckBcwIXlP&
return findPageByCriteria ,*Tf9=z
]P<u^ `{*
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7d]}BLpjWz
} VjBV2 x
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public PaginationSupport findPageByCriteria ib0M$Y1tIS
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(final DetachedCriteria detachedCriteria, finalint "e0$/WQ6J
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startIndex){ S2kFdx*Zf
return findPageByCriteria 8Sd<!
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(detachedCriteria, PaginationSupport.PAGESIZE, (q59cA w~X
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startIndex); 0WaC.C+2i
} BRPvBs?Q,{
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public PaginationSupport findPageByCriteria 9i*t3W71]
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(final DetachedCriteria detachedCriteria, finalint $d3al%Uo
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pageSize, Fo=Icvo
finalint startIndex){ {~_X-g5|]
return(PaginationSupport) c3W9"
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getHibernateTemplate().execute(new HibernateCallback(){ yl/-!
publicObject doInHibernate rU=qr&f"B
{?!=~vp
(Session session)throws HibernateException { 9=O`?$y
Criteria criteria = `w` f[dU-
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detachedCriteria.getExecutableCriteria(session); As
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int totalCount = {4J:t_<nKO
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((Integer) criteria.setProjection(Projections.rowCount l2vIKc
%N$,1=0*
()).uniqueResult()).intValue(); D[32t0
criteria.setProjection .<%2ON_
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(null); E}LuWFZ&
List items = _;L%? -2c
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criteria.setFirstResult(startIndex).setMaxResults }N[|2nR'
sQUJ]h
(pageSize).list(); "Zm**h.t
PaginationSupport ps = & mwQj<Z
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new PaginationSupport(items, totalCount, pageSize, +a1Or
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startIndex); .'foS>W=t
return ps; tljZE)
} <LL+\kfTZO
}, true); Sk7l&B
} nb-]fa
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public List findAllByCriteria(final #gn{X!;-;
_3@[S
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DetachedCriteria detachedCriteria){ yvR3|
return(List) getHibernateTemplate `#@#eZ
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().execute(new HibernateCallback(){ )aSj!X'`;
publicObject doInHibernate .)=T1^[hI
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(Session session)throws HibernateException { *nS}1(u]
Criteria criteria = i!0w? /g9
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detachedCriteria.getExecutableCriteria(session); "/H B#
return criteria.list(); )gF>nNE
} h,-2+}
}, true); X 4L"M%i
} K^32nQX
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public int getCountByCriteria(final PL"u^G`
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DetachedCriteria detachedCriteria){ D)shWJRlvW
Integer count = (Integer) wavyREK
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getHibernateTemplate().execute(new HibernateCallback(){ B|9[DNd
publicObject doInHibernate W5i{W'
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(Session session)throws HibernateException { m\*;Fx
Criteria criteria = f2h`bO
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detachedCriteria.getExecutableCriteria(session); ;OC~,?O5
return oZ]^zzoEcg
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criteria.setProjection(Projections.rowCount $-^
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()).uniqueResult(); ohEIr2
} F:$*0!
}, true); Dh+<|6mx
return count.intValue(); z`]sWi F0
} QC\r|RXW
} <Wrn/%tL
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用户在web层构造查询条件detachedCriteria,和可选的 FTgqE@
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 k'6x_
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PaginationSupport的实例ps。 =w !>/#U
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ps.getItems()得到已分页好的结果集 zrDcO~w
ps.getIndexes()得到分页索引的数组 $I0&I[_LzK
ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 r;n^\[Ov0,
ps.getNextIndex()下一页索引 :<p3L!?8y
ps.getPreviousIndex()上一页索引 R1cOUV,y[/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \+Nn>wW.
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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 'Lu d=u{
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: QnJd}(yN
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首先,为了实现分页查询,我封装了一个Page类: Hb&C;lk
java代码: %\f<N1~*
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/*Created on 2005-4-14*/ dBm!`;r4
package org.flyware.util.page; vu@@!cT6e
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/** @1vpkB~ w
* @author Joa )+ (GE
* gmUX
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*/ vqhu%ZyP
publicclass Page { _uL8TC^
a7U`/*
/** imply if the page has previous page */ bZ SaL^^(
privateboolean hasPrePage; ugV/#v O
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/** imply if the page has next page */ i'YM9*yN
privateboolean hasNextPage; +/>XOY|Ie
P>nz8NRq
/** the number of every page */ 'T+v&M
privateint everyPage; f0@4>\g
eWGaGRem
/** the total page number */ ET0^_yk
privateint totalPage; AfT;IG%Gt
) :VF^"
/** the number of current page */ Y52TC@'
privateint currentPage; 5~FXy{ZIH
/B!Ik:c}
/** the begin index of the records by the current v"YaMbu
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query */ YH,u*.I^/
privateint beginIndex; g1{2E<b5
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/** The default constructor */ kXN8hU}iq
public Page(){ R ~? 9+
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is
} \AOHZ r
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/** construct the page by everyPage cqG&n0zb
* @param everyPage /0YO`])"
* */ :h8-y&;
public Page(int everyPage){ Gp0yRT.
this.everyPage = everyPage; cT|aQM@iW
}
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/** The whole constructor */ |wM<n
public Page(boolean hasPrePage, boolean hasNextPage, 6<o2 0(?
8}Cp(z2
AhU
int everyPage, int totalPage, CHckmCgf4
int currentPage, int beginIndex){ AOM@~qyc
this.hasPrePage = hasPrePage; 3S"kw
this.hasNextPage = hasNextPage; ('6sW/F*ab
this.everyPage = everyPage; H;N6X y*~
this.totalPage = totalPage; y:YJv x6&4
this.currentPage = currentPage; q0*d*j F0u
this.beginIndex = beginIndex; F;8Uvj
} o(stXa
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/** YP`/dX"4
* @return FO:k
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* Returns the beginIndex. rm%MQmF
*/ 534DAhpD=.
publicint getBeginIndex(){ ZC97Z sE
return beginIndex; cD'|zH]
} 8,L)=3m-
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/** 7OD2/{]5
* @param beginIndex &?*H`5#?G
* The beginIndex to set. i#I7ncX
*/ hQ}y(2A.XI
publicvoid setBeginIndex(int beginIndex){ TG6E^3a P
this.beginIndex = beginIndex; Qe;R3D=T;
} .R_-$/ZP
cH`ziZ<&m1
/** -eFq^KP2
* @return ebiOR1)sN
* Returns the currentPage. R6`,}<A]@
*/ 4tlLh`-8
publicint getCurrentPage(){ $bF3v=u`
return currentPage; )sLXtV)nm6
} Q\pI\]p:
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/** 'RpX&g
* @param currentPage r2=4Wx4(
* The currentPage to set. {YIf rM
*/ Su]p6B
publicvoid setCurrentPage(int currentPage){ m`xzvg
this.currentPage = currentPage; "qhQJql
} >dfk2.6e
k3UKGP1
/** [&+5E1%L
* @return S8Yti
* Returns the everyPage. M,g$
*/ Y))x'<T'Q
publicint getEveryPage(){ ?@H/;hB[|
return everyPage; cIg+^Tl
} ^v&)z,
Rv|X\Wm
/** u5A$VRMN
* @param everyPage |g!3f
* The everyPage to set. wY*tq{7
*/ :,Mg1Zf
publicvoid setEveryPage(int everyPage){ RP%7M8V){B
this.everyPage = everyPage; C n.x:I@r
} h[oI/X
A;7At!kK
/** iJ p E`
* @return t{Z:N']H
* Returns the hasNextPage. O_^;wey0}?
*/ ;fZ9:WB
publicboolean getHasNextPage(){ Z?)=4|
return hasNextPage; W*9*^
} E\vW>g*W
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/** wD5fm5r=
* @param hasNextPage hi^t zpy
* The hasNextPage to set. x"{WLZ
*/ 9_lWB6
publicvoid setHasNextPage(boolean hasNextPage){ ok(dCAKP
this.hasNextPage = hasNextPage; YxWA]
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} v_I)eac z
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/** %>EM ^Z
* @return R3@luT]
* Returns the hasPrePage. l@`Do [
*/ =k:yBswi
publicboolean getHasPrePage(){ @h!nVf%fe
return hasPrePage; ';3#t(J;
}
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o
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/** % jSB9
* @param hasPrePage Ms14]M[\
* The hasPrePage to set. `,$PRN"]
*/ ZHimS7
publicvoid setHasPrePage(boolean hasPrePage){ !M;><b}=5
this.hasPrePage = hasPrePage; Q<T+t0G\O-
} tWaM+W
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/** 4N8(WI"4S
* @return Returns the totalPage. N^%7
* f8S! FGiNc
*/ lB*HLC
publicint getTotalPage(){ Z!2%{HQ=q
return totalPage; 4x"9Wr=}
} 4^_'LiX3[
Cnv?0to2l
/** T':} p2}w+
* @param totalPage 5DmW5w'p
* The totalPage to set. #}S<O_
*/ }fh<L CwTi
publicvoid setTotalPage(int totalPage){ q6EZ?bo{
this.totalPage = totalPage; FgnPh%[u
} PgdHH:v)
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} D8f4X
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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 ,$(a,`s)
2 `U+
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个PageUtil,负责对Page对象进行构造: D+"+m%^>C
java代码: v4vIcHDs
X ;Cl8
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/*Created on 2005-4-14*/ :N64FR#
package org.flyware.util.page; Jsf"h-)P
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import org.apache.commons.logging.Log; SGP)A(,k9
import org.apache.commons.logging.LogFactory; 8:fq!m
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/** V,&A?
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* @author Joa qh#?a'
* RX?y}BDo0
*/ G_S2Q @|Q
publicclass PageUtil { 2Z+:^5
*9tRhRc
privatestaticfinal Log logger = LogFactory.getLog _&e$?hY
7'.]fs:
(PageUtil.class); 0+Z?9$a1
Iad&Z8E
/** <lTLz$QE
* Use the origin page to create a new page #Q@~TW
* @param page 7mA:~- .u
* @param totalRecords r<5i
* @return Y|cj&<o
*/ T\w{&3ONm
publicstatic Page createPage(Page page, int }6!m Q
_~bG[lX !
totalRecords){ SAhk `_
return createPage(page.getEveryPage(), Z $Fm73
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page.getCurrentPage(), totalRecords); @t2S"s$m
} _K3;$2d|R
7gE/g`"#
/** c7A]\1 ~
* the basic page utils not including exception 9QHV%%
}U@(S>,%
handler 9k;%R5(
* @param everyPage wL[{6wL
* @param currentPage m1Xc3=Y
* @param totalRecords -{ES 36
* @return page }#2I/dn
*/ 7V-uQ)*
publicstatic Page createPage(int everyPage, int i2E@5 v=|Y
v(;n|=O
currentPage, int totalRecords){ `]F#j ]"
everyPage = getEveryPage(everyPage); ZuT5}XxF
currentPage = getCurrentPage(currentPage); 1F R
int beginIndex = getBeginIndex(everyPage, *_@$"9
v9"03=h
currentPage); ;%Kh~
int totalPage = getTotalPage(everyPage, LerRrN}~
x:+]^?}r
totalRecords); rPK 1#
boolean hasNextPage = hasNextPage(currentPage, 7{p6&xXx
dy4~~~^A
totalPage); auAwZi/
boolean hasPrePage = hasPrePage(currentPage); t'[`"pp=
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returnnew Page(hasPrePage, hasNextPage, H`
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everyPage, totalPage, S|]\q-qA&
currentPage, gP`CQ0t
d "25e"(~F
beginIndex); S5[}kfe
} 7A^L$TY
ZhFlR*EQ
privatestaticint getEveryPage(int everyPage){ X'p%K/-m
return everyPage == 0 ? 10 : everyPage; NUh+ &M
} ?hKpJA'%
|#zj~>7?
privatestaticint getCurrentPage(int currentPage){ 5=Il2
return currentPage == 0 ? 1 : currentPage; 7`tJ/xtMy;
} EzU3'x
vf-8DB
privatestaticint getBeginIndex(int everyPage, int ]Xg7XY
{J-Ojw|Y b
currentPage){ H^+Znmo
return(currentPage - 1) * everyPage; e17]{6y
} NmTo/5s
ZQAiuea
privatestaticint getTotalPage(int everyPage, int yT[)V[}
,6aF~p;wI|
totalRecords){ 5%w08
int totalPage = 0; \S>GtlQbn
d$y?py
if(totalRecords % everyPage == 0) {?Cm
totalPage = totalRecords / everyPage; MP~+@0cv
else I "HEXsSe
totalPage = totalRecords / everyPage + 1 ; /%TL{k&m$
iUlSRfrC$#
return totalPage; q^6l`JJ
} 8|tnhA]~
uP.dCs9-
privatestaticboolean hasPrePage(int currentPage){ tk+4noA
return currentPage == 1 ? false : true; Wa9yyc
} W!JEl|]
~YXkAS:
privatestaticboolean hasNextPage(int currentPage, gnlU
;&XC*R+
int totalPage){ i<*W,D6
return currentPage == totalPage || totalPage == meZZQ:eSl
c9Q _Qr0'
0 ? false : true; .gY=<bG/fA
} 2:&L|;
xXCsJ9]
ne%(`XY{Q]
} + aWcK6
Li9>RY+3
;<#=|eD2
0a:@DOzT
Wm/0Pi
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 4ULdf|o P"
FY
pspv?4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ?;ZnD(4?
C)ic;!$Qhb
做法如下: V6_~"pRR=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 L&&AK`Ur3l
<GSp%r
的信息,和一个结果集List:
_+}f@&"
java代码: oo|Nu+
;#=y5Q4
'`j MNKn\
/*Created on 2005-6-13*/ OV`li#H
package com.adt.bo; J:G{
W&7(
import java.util.List; 9]:F!d/
fvj
import org.flyware.util.page.Page; yh{U!hG
AsR}qqG
/** Wz;@Rl|F
* @author Joa y 7z)lBy\
*/ %`lLX/4~
publicclass Result { >]kZ2gVt
o w;a7
private Page page; s` =&l
3|D .r-Q
private List content; f{h2>nEj\
v.c.5@%%o
/** *S'?u_Y7
* The default constructor h$p}/A
*/ oz7=1;r
public Result(){ Qjmo{'d
super(); zpg512\y
} {FR+a**
9Dd`x7$a
/** g|M>C:ZT
* The constructor using fields ~Xc1y!"9*
* j|@8VxZ
* @param page 6O" y
* @param content : :928y
*/ (&M,rW~Qxs
public Result(Page page, List content){ GN+!o($
this.page = page; /!U(/
this.content = content; A-u!{F
} g\ H~Y@'{
2Hk21y\
/** $F6GCM3Cx
* @return Returns the content. G`f|#-}
*/ |}@teN^J*U
publicList getContent(){ bVr`a*EM
return content; lU.aDmy<
} |(uo@-U
V-18~+F~"a
/** n!U1cB{
* @return Returns the page. 6n
H'NNS:J
*/ w I[Hoi
V
public Page getPage(){ Nhtc^DX
return page; WLH ;{
} a!.Y@o5Ku
k=X)axt1
/** q[x|tO
* @param content *r ('A
* The content to set. XII',&
*/ rd,!-w5
public void setContent(List content){ )"%J~:`h}
this.content = content; **c"}S6:mC
} "ZuA._
\"d\b><R
/** uCgJF@
* @param page be [E^%
* The page to set. i]& >+R<6
*/
I p|[
publicvoid setPage(Page page){ 4^!%>V"d/
this.page = page; |#Q0UM|'Q
} EmyE%$*T
} 1w+)ne_&
gFXz:!A
31N5dIi,
f n8|@)J
Q)5V3Q]@^
2. 编写业务逻辑接口,并实现它(UserManager, TXqtE("BDl
!E^\)=E)P
UserManagerImpl) @ ZN@EOM$+
java代码: +ijxv
\
*A!@T
WUb] 8$n
/*Created on 2005-7-15*/ NKiWt
Z"
package com.adt.service; _jaB[Q=By
<slrzc_>&
import net.sf.hibernate.HibernateException; c`oW-K{
]Mvpec_B
import org.flyware.util.page.Page; o+}G/*O8
PB~
r7O]
import com.adt.bo.Result; ak{XLzn
!:v7SRUXb
/** \T?6TDZ]
* @author Joa bpa'`sf
*/ !PgwFJ
publicinterface UserManager { W9S6
SO^\
h r6?9RJY
public Result listUser(Page page)throws N9~'\O$'7
<&tdyAT?&
HibernateException; GQ sE5Vb
PoLk{{l3
} Z7k ku:9
%8>0;ktU
^OK;swDW
'f8'|o)
;_0frX
java代码: $y%IM`/w
GE=PaYz
>[Tt'.S!?
/*Created on 2005-7-15*/ RL*b47,
package com.adt.service.impl; Sa/]81aG
.etG>tH
import java.util.List; H;#C NB<e
g"\JiBb5
import net.sf.hibernate.HibernateException; q``/7
_/YM@%d
import org.flyware.util.page.Page; arvKJmD
import org.flyware.util.page.PageUtil; \uZ1Sl
a3,A_M}M'
import com.adt.bo.Result; V5gr-^E
import com.adt.dao.UserDAO; V`G^Jyj
import com.adt.exception.ObjectNotFoundException; 9U3 .=J
import com.adt.service.UserManager; i?,\>LTG
AEUR`.
/** OF,_6"m
* @author Joa _>3#dk
*/ E&)o.l<h|
publicclass UserManagerImpl implements UserManager { <v?2p{U%
g'2}Y5m$`
private UserDAO userDAO; Hm+VGH'H?
L1&` 3a?pL
/** {U4{v=,!I
* @param userDAO The userDAO to set. X]dN1/_
*/ W*/2x8$d
publicvoid setUserDAO(UserDAO userDAO){ 2iC BF-,
this.userDAO = userDAO; QHd|cg
} /JIVp_-p
E+/XKF
/* (non-Javadoc) O`Htdnu
* @see com.adt.service.UserManager#listUser 09i77
j$4lyDfD
(org.flyware.util.page.Page) L@J$kqWY
*/ V7vojm4O
public Result listUser(Page page)throws y,`q6(&
=w<iYO
HibernateException, ObjectNotFoundException { u++a0>N
int totalRecords = userDAO.getUserCount(); N:EljzvP}
if(totalRecords == 0) QBA{*@ A-
throw new ObjectNotFoundException rddn"~lm1
HUbXJsSP
("userNotExist"); Q+'fTmT[,
page = PageUtil.createPage(page, totalRecords); s"~,Zzy@j
List users = userDAO.getUserByPage(page);
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returnnew Result(page, users); 5f75r
} J ayax]u7J
ob/HO(h3
} "&\(:#L
.!'rI7Kz'i
DLO#_t^v.
COd~H
ssmJ?sl
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )=5*iWe
9e&*++vf
询,接下来编写UserDAO的代码: 0|{":i_s
3. UserDAO 和 UserDAOImpl: S<5.}c R
java代码: @@}muW>;T
Ko
"JH=<
G$~hAZ
/*Created on 2005-7-15*/ bHzZ4i
package com.adt.dao; ]ed7Q3lq
UM'JK#P"
import java.util.List; X*e:MRw[
\;+b1
import org.flyware.util.page.Page; u%Z4 8wr
FH;)5GGnv
import net.sf.hibernate.HibernateException; 5yp
VD{_6
/** rNgAzH
* @author Joa ^(:n a6C
*/ s3~6[T?8
publicinterface UserDAO extends BaseDAO { Nt[&rO3s
+ Cq&~<B
publicList getUserByName(String name)throws 5=!aq\
5
!V/p.O
HibernateException; b+BX >$
,- _ReL
publicint getUserCount()throws HibernateException; By<~h/uJ
4Q\~l(
publicList getUserByPage(Page page)throws O)r>AdLGn
;=8@@9
HibernateException; /ZSdY_%s
?[lKft
} dw7h@9\y
KpO%)M!/Z#
{1GIiP-U
2f9%HX(5
;fv/s]X86I
java代码: vpk~,D07yR
,q
Bu5t
zrur-i$N+
/*Created on 2005-7-15*/ }$s._)a
package com.adt.dao.impl; qV@H u/;
f=40_5a6
import java.util.List; ` ln=D$
pB,@<\l %
import org.flyware.util.page.Page; &E!-~'|z
U,$^|Iz
import net.sf.hibernate.HibernateException;
Pe7%
9
import net.sf.hibernate.Query; _NM=9cWd
lb #`f,r>
import com.adt.dao.UserDAO; $ZE"o`=7
F}#=qBa[
/** YZ+<+`Mz<
* @author Joa %5?0+~
*/ a~[]Ye@H
public class UserDAOImpl extends BaseDAOHibernateImpl $RV'DQO
[Uu!:SZ
implements UserDAO { cBnB(t%
%g%#=a;]q
/* (non-Javadoc) N/mC,7Q
* @see com.adt.dao.UserDAO#getUserByName y]E ?\03"
XAc#ywophi
(java.lang.String) ^'aMp}3iu
*/ las|ougLy
publicList getUserByName(String name)throws ;-T%sRI:|
0@8EIQxK"
HibernateException { o@G
<[X|ke
String querySentence = "FROM user in class 6 {tW$q
tr\}lfK%
com.adt.po.User WHERE user.name=:name"; zi}dQsy6
Query query = getSession().createQuery Wtwh.\Jba
Y vjRJ
(querySentence); c>RS~/Y
query.setParameter("name", name); 9l:Bum)9
return query.list(); c~+l|r=u?
} skP2IMa75
pjX')i<
/* (non-Javadoc) W.AN0N
* @see com.adt.dao.UserDAO#getUserCount() `$D2w|
*/ hE>i~:~R
publicint getUserCount()throws HibernateException { }$|uIS
int count = 0; &Q"Ox{~W
String querySentence = "SELECT count(*) FROM zy9# *gGq
nAJ<@a
user in class com.adt.po.User"; niV= Ijt{5
Query query = getSession().createQuery v1Lu.JQC$
?gMxGH:B.&
(querySentence);
D=nuK25
count = ((Integer)query.iterate().next 1[vmK,N=E
N8|
;X
()).intValue(); VL/%D*
return count; QviH+9
} czf|c
u;Q'xuo3
/* (non-Javadoc) AtN=G"c>_
* @see com.adt.dao.UserDAO#getUserByPage \$Nx`daFi
tF<|Eja*
(org.flyware.util.page.Page) MNKB4C8>
*/ KN;b+`x;M
publicList getUserByPage(Page page)throws H`$s63
nkp!kqJ09
HibernateException { i#
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String querySentence = "FROM user in class f`?Y+nu}
:*"0o{
ie
com.adt.po.User"; <=*xwI&q
Query query = getSession().createQuery sSC yjS'T
ZgL4$%
(querySentence); 3Q`F x
query.setFirstResult(page.getBeginIndex()) yD+)!q"
.setMaxResults(page.getEveryPage()); vb-L "S?kC
return query.list(); MH`H[2<\!,
} RbJ,J)C>
mB.kV Ve0
} 88
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;N4b~k)
)Aa98Eu?2
O1Gd_wDC/i
-<jb>8
至此,一个完整的分页程序完成。前台的只需要调用 sY=fS2b#)
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userManager.listUser(page)即可得到一个Page对象和结果集对象 ANy=f-V
|*0oz=
的综合体,而传入的参数page对象则可以由前台传入,如果用 Cyxt EzPp
~l%Dcp
webwork,甚至可以直接在配置文件中指定。 !6ZkLE[XJ<
}*m:zD@8$
下面给出一个webwork调用示例: C26PQGo#$
java代码: R/M:~h~F!
]BU,*YaB
@4m_\]Wy
/*Created on 2005-6-17*/ Pq~"`-h7:
package com.adt.action.user; gOZ$rv^g
YBN.
waL
import java.util.List; #F.;N<a
XB-pOtVm
import org.apache.commons.logging.Log; '+NmHu:q
import org.apache.commons.logging.LogFactory; wHk4BWg-
import org.flyware.util.page.Page; EVMhc"L
Xd>4n7nb$`
import com.adt.bo.Result; .
zvF!!z
import com.adt.service.UserService; ~zFs/(k
import com.opensymphony.xwork.Action; dRyK'Xr
)'xTDi
/** oYnA 3
* @author Joa b5
YE4h8%
*/ "g\
publicclass ListUser implementsAction{ J[;c}
k/O|ia6
privatestaticfinal Log logger = LogFactory.getLog {Q?AIp6u|
X3I\O,"I
(ListUser.class); I@a7AuOw
;Yyg(Ex
private UserService userService; 8Vv"'CU#
1agyT
private Page page; 3Ec5:Caz
F'W{\4
privateList users; BD[XP`[{
Yva^JB
/* g/W<;o<v(I
* (non-Javadoc) ~N;.hU%l
* Gk*Mx6|N
* @see com.opensymphony.xwork.Action#execute() afv?z
*/ -]R7[5C:
publicString execute()throwsException{ eP|:b &
Result result = userService.listUser(page); gzvEy^X
page = result.getPage(); 0tm%Kd
users = result.getContent(); Q1IN@Db}y
return SUCCESS; QS,IM>Nr
} iDlIx8PI
3/>McZ@OH
/** K5z*DYT
* @return Returns the page. g4&zBn
*/ kWc%u-_
public Page getPage(){ K&
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return page; #IA[erf:
} uI@:\Rss
FEw51a+V
/** 2[LT!TT
* @return Returns the users. "2}04b|"
*/ ;FQAL@"Yj
publicList getUsers(){ *qj @y'1\
return users; 4Z"DF)+}
} !m^;Apuy
s\1h=V)!H
/** 7gfNe kr~W
* @param page q-eC=!#}
* The page to set. PQ<""_S||
*/ BhLYLlXPY
publicvoid setPage(Page page){ =\AI92
this.page = page;
1Wtr_A
} \eH~1@\S
}H!c9Y
/** [MdVgJ9'
* @param users VmHok
* The users to set. ZOK2BCoW
*/ dE^:-t
publicvoid setUsers(List users){ Uc>kCBCd
this.users = users; Mi,yg=V
} 6A;V[3
"n,">
/** L
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* @param userService h^D?G2O
* The userService to set. RmY5/IYR|:
*/ b%L8mX
publicvoid setUserService(UserService userService){ TDs=VTd@Z
this.userService = userService; B/:q
} !JzM<hyg3
} fchsn*R%-
n@XI$>B
B^P)(Nu+
UX;?~X
VUxuX5B3M
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ZZ?0%9
E?z3 D*U
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 [-_3Zr
IP7j)SM!
么只需要: qc2j}D0
java代码: q,F\8M\$
ri1D*CS
zR6,?Tzg
<?xml version="1.0"?> ('xIFi
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork zUXQl{
I'HPy.PV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Zy|B~.@<j
D+P(
1.0.dtd"> F{0Z
BaZ$p O^
<xwork> 'FgBYy/
_t||v
<package name="user" extends="webwork- X0Y1I}gD
,Md8A`7x~
interceptors"> $wg5q\Rv
1PpZ*YK3z
<!-- The default interceptor stack name V
zuW]"
:m]~o3KRy
--> p:Ry F4{b2
<default-interceptor-ref ayfR{RYi
~7+7{9g
name="myDefaultWebStack"/> GPz0qK
_v bCC7Bf8
<action name="listUser" C-E~z{
$nF|n+m
class="com.adt.action.user.ListUser"> `ltc)$
<param 1DgRV7
z`$jxSLm
name="page.everyPage">10</param> r*HbglB
<result #%N v\g;
p4GhT~)l:
name="success">/user/user_list.jsp</result> Z^E>)!t
</action> #V&98 F
3.@"GS#"[
</package> m0QE
S
6!zBLIYFI
</xwork> )12.W=p
{,NGxqhE
JJ_b{ao<
:dq.@:+<R
94VtGg=b}
J{;XNf =
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 KBE3q)
.2"-N5Z
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 m:B9~lbT+
E@ J/_l;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 M2H +1ic
uonCD8
#(swVo:+E
]8q#@%v}
[ )3rc}:1
我写的一个用于分页的类,用了泛型了,hoho */c4b:s
Lh%z2 5t
java代码: WoM;) Q
-]el_:H
E|{(O
package com.intokr.util; %"-bG'Yc
<G|i!Pm
import java.util.List; j5m KJC
!q\MXS($#u
/** ]QKo>7%[
* 用于分页的类<br> p3r("\Za,
* 可以用于传递查询的结果也可以用于传送查询的参数<br> GsIVx!
* 6_|iXs(&
* @version 0.01 b S-o86u
* @author cheng bGw56s'R5~
*/ ` _aX>fw
public class Paginator<E> { ICck 0S!
privateint count = 0; // 总记录数 A0hKzj
privateint p = 1; // 页编号 !LI6_Oq
privateint num = 20; // 每页的记录数 DW(
/[jo\
privateList<E> results = null; // 结果 F+o4f3N
%,T=|5
/** M[ {O%!
* 结果总数 YI+ clh;%9
*/ F>Pr`T?>
publicint getCount(){ Q^\m@7O
:
return count; _%g L
} P:D;w2'Q
8\WV.+
publicvoid setCount(int count){ RW~!)^
this.count = count; yY[9\!
} q QcQnd2K
mR["xDHD
/** ^'9.VVyz
* 本结果所在的页码,从1开始 w*?SGW
* %xt;&HE
* @return Returns the pageNo. >?<S(
*/ Tp46K\}Uf
publicint getP(){ 8Q%g<jX*
return p; CvhVV"n
} >$$z 6A[
CbGfVdw/c
/** FKZ'6KM&A
* if(p<=0) p=1 yPrF2@#XZ/
* Sq&r
;
* @param p ?f}?I`S,
*/ 1aI&jdJk
publicvoid setP(int p){ p{
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if(p <= 0) ziDvDu=
p = 1; vtq$@#?~ b
this.p = p; xU/7}='T
} |kY}G3/
M*!WXQlud
/** xXf,j#`"
* 每页记录数量 .n n&K}h
*/ gY'-C
publicint getNum(){ u6nO\.TTtY
return num; +m9ouF
} \sBXS.
N5[^W`Qf
/** ho-#Xbq#g
* if(num<1) num=1 /KLkrW
*/ zmU@ k
publicvoid setNum(int num){ SZ29B
if(num < 1) l+#J oc<8
num = 1; 0iYo&q'n
this.num = num; @)\4 $#+-
}
|nCVM\+5T
80zpRU"
/** #x qiGK
* 获得总页数 ]_BH"ng}
*/ Q,K$)bM
publicint getPageNum(){ ({ O~O5k
return(count - 1) / num + 1; %pIP#y[4
} {E; bT|3z
G9^xv
/** vgE
-t
* 获得本页的开始编号,为 (p-1)*num+1 )I#{\^
*/ mC0_rN^Aj
publicint getStart(){ - "NK"nb
return(p - 1) * num + 1; #c!rx%8I
} Lqdapx"Z_
}DQTy.d;P
/** 78 w
* @return Returns the results. U9ZuD40\
*/ lA%FS]vh
publicList<E> getResults(){ |
C^.[)
return results; %x.du9
} -woFKAy`
|Fz ^(US
public void setResults(List<E> results){ Bn9#F#F<
this.results = results; d~AL4~}
} "fr{:'HX
eTFep^[
public String toString(){ CT5s`v!s
StringBuilder buff = new StringBuilder EK=
y!>
4Q/{lqG
(); 2"HTD|yy
buff.append("{"); m.p$f$A_
buff.append("count:").append(count); ; PncJe5x
buff.append(",p:").append(p); ufCpX>lNF
buff.append(",nump:").append(num); X;H\u6-|>6
buff.append(",results:").append NXQ=8o9,9
!zvjgDlZv
(results); n$N$OFuO
buff.append("}"); jQxhR
return buff.toString(); Ui!l3_O
} cF4,dnI
PW|=IPS
} CIz0Gjtx6m
lP*n%Pn)
>{QO$F#