Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >~}}*yp
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;{j@ia
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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 ->9waXRDz)
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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 NG+%H1!$_
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分页支持类: #Fkn-/nL
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java代码: tNf_,]u
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package com.javaeye.common.util; ./qbWr`L
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import java.util.List; MhDPf]`
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publicclass PaginationSupport { $z,rN\[
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publicfinalstaticint PAGESIZE = 30; P0c6?K6 j
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privateint pageSize = PAGESIZE; kN g{
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privateList items; bbG!Fg=qQ?
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privateint totalCount; SdXAL
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privateint[] indexes = newint[0]; 0c
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privateint startIndex = 0; -~NjZ=vPh
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public PaginationSupport(List items, int SYYg
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totalCount){ k =
setPageSize(PAGESIZE); GLiD,QX<
setTotalCount(totalCount); R<Uu(-O-
setItems(items); y.aeXlc[
setStartIndex(0); LL%s$>c65A
} uB;PaZG?{
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public PaginationSupport(List items, int
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totalCount, int startIndex){ z^Y4:^L~I
setPageSize(PAGESIZE); i*61i0
setTotalCount(totalCount); Tqm)- |[
setItems(items); jRBKy8?[C
setStartIndex(startIndex); Ih_=yk
} )YPut.
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public PaginationSupport(List items, int 4"et4Y7
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totalCount, int pageSize, int startIndex){ 7e/K YS+!s
setPageSize(pageSize); 83pXj=k<
setTotalCount(totalCount); |IZFWZd
setItems(items); um=qT)/D
setStartIndex(startIndex); |>dqZ_)v
} 5;[h&jH
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publicList getItems(){ .B_a3K4'{^
return items; YPmgR]=6
} (i@B+c
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publicvoid setItems(List items){ fctVJ{?
this.items = items; V_P,~!
} /_ RrNzqy
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publicint getPageSize(){ en8l:INX
return pageSize; AkX8v66:
} NGAjajB
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publicvoid setPageSize(int pageSize){ >mp"=Y
this.pageSize = pageSize; 5^e|802
} G]E-2 _t7
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publicint getTotalCount(){ mApl}I
return totalCount; q/dja
} BE,H`G #h
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publicvoid setTotalCount(int totalCount){ _<7e5VR
if(totalCount > 0){ ;#n+$Q#:
this.totalCount = totalCount; L=)Arj@q
int count = totalCount / X0BBJ( e
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pageSize; !^IAn
if(totalCount % pageSize > 0) x`Ik747^v
count++; o]WG8Mo-
indexes = newint[count]; X@^"@
for(int i = 0; i < count; i++){ 7rjS.
indexes = pageSize * VN
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i; <lf6gb
} \Z/#s;c,4
}else{ i1-wzI
this.totalCount = 0;
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} }x+s5a;!3/
} "dFuQB
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publicint[] getIndexes(){ hC2_Yr>N%
return indexes; RrRE$g
} =Y<RG"]a&J
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publicvoid setIndexes(int[] indexes){ UO8./%'
this.indexes = indexes; t(\P8J
} ~,O}wT6q
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publicint getStartIndex(){ rRd8W}B
return startIndex; "Rq)%o$Z
}
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publicvoid setStartIndex(int startIndex){ &?#!%Ds
if(totalCount <= 0) z|WDqB%/I
this.startIndex = 0; Nh+ZSV4WJ:
elseif(startIndex >= totalCount) .>+jtp}
this.startIndex = indexes p WLFJH}N
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[indexes.length - 1]; '`/w%OEVC5
elseif(startIndex < 0) O>Ao#_*hOb
this.startIndex = 0; <"}WpT
else{ 3`>nQ4zC
this.startIndex = indexes "|%'/p
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[startIndex / pageSize]; jjU("b=
} NiO|Aki{
} ^laf!kIP
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publicint getNextIndex(){ UWW_[dJr
int nextIndex = getStartIndex() + hwB>@r2
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pageSize; Wz-7oP%;I
if(nextIndex >= totalCount) B4ky%gF4
return getStartIndex(); -40OS=wpA
else -8D$ [@y(
return nextIndex; =3<@{^Eg
} N[8y+2SZ
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publicint getPreviousIndex(){ O/bpm-h`8c
int previousIndex = getStartIndex() - rhvTV(Bz
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pageSize; 4&/m>%r
if(previousIndex < 0) EE[JXoke
return0; c&u~M=EW
else J<=k
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return previousIndex; /%5X:*:H
} QP0[
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} +Rb0:r>kU
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抽象业务类 fY{&W@#g
java代码: Ceco^Mw
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/** - |j4u#z
* Created on 2005-7-12 Ss
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*/ 2$%E:J+2:$
package com.javaeye.common.business; >Pw
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import java.io.Serializable; sCw X|
import java.util.List; EABy<i
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import org.hibernate.Criteria; 990sE
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import org.hibernate.HibernateException; X'KkIo
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import org.hibernate.Session; 9;k!dM
import org.hibernate.criterion.DetachedCriteria; XVNJ3/
import org.hibernate.criterion.Projections; GO=3<Q{;
import )OgQ&,#
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org.springframework.orm.hibernate3.HibernateCallback; 6m!%X GZT
import i%a jL
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org.springframework.orm.hibernate3.support.HibernateDaoS qD?-&>dBWi
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upport; T%p/(
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import com.javaeye.common.util.PaginationSupport; =(U&?1 R4
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public abstract class AbstractManager extends [r"`rBw
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HibernateDaoSupport { BO3%p
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privateboolean cacheQueries = false; Q'n]+%YN
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privateString queryCacheRegion; Rr0@F`"R
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publicvoid setCacheQueries(boolean %.3]F2_Q
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cacheQueries){ jQLiqi`
this.cacheQueries = cacheQueries; %.+#e
} =fZMute
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publicvoid setQueryCacheRegion(String AyUiX2=w1
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queryCacheRegion){ %juR6zB%8
this.queryCacheRegion = F4%vEn\!
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queryCacheRegion; jaq`A'o5
} WnL Ma|e
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publicvoid save(finalObject entity){ $pOgFA1'
getHibernateTemplate().save(entity); +bv-! rf
} Ar:ezA
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publicvoid persist(finalObject entity){ )^'g2gVK+p
getHibernateTemplate().save(entity); Z(=UZI?
} t@1bu$y
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publicvoid update(finalObject entity){ !04zWYHo
getHibernateTemplate().update(entity); y Ddi+
} gE~]^B{
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publicvoid delete(finalObject entity){ %oY=.Ok ]
getHibernateTemplate().delete(entity); Xzp!X({
} Im* ~6[
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publicObject load(finalClass entity, h72#AN
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finalSerializable id){ F:o<E 42
return getHibernateTemplate().load Qso"jYl<
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(entity, id); 3?rYt:Uf!
} 8w|-7$ v
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publicObject get(finalClass entity, F3L'f2yBG
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finalSerializable id){ u{_jweZ
return getHibernateTemplate().get QIg.r\>o
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(entity, id); NLLLt
} O5:2B\B
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publicList findAll(finalClass entity){ #~Z55D_
return getHibernateTemplate().find("from !y{t}|U/d
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" + entity.getName()); apxY2oE&
} P}kp_l27
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publicList findByNamedQuery(finalString A&:i$`m,
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namedQuery){ s^n}m#T
return getHibernateTemplate ]$VYzE2e
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().findByNamedQuery(namedQuery); :172I1|7
} 2W_p)8t>b
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publicList findByNamedQuery(finalString query, [z^db0PU
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finalObject parameter){ AUk,sCxd
return getHibernateTemplate 3i c6!T#t"
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().findByNamedQuery(query, parameter); )t-Jc+*A>
} wf=
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publicList findByNamedQuery(finalString query, y
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finalObject[] parameters){
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return getHibernateTemplate ~baVS-v
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().findByNamedQuery(query, parameters); BV8-\R@
} ?1G7=R
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publicList find(finalString query){ lhk[U!>#
return getHibernateTemplate().find .|pyloL.
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(query); 2KUm(B.I
} @DYxDap{
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publicList find(finalString query, finalObject P9\!JH!
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parameter){ `a!:-.:v
return getHibernateTemplate().find !p4y@U{
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(query, parameter); (|F } B
} c)HHc0KD
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public PaginationSupport findPageByCriteria J*lKXFq7
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(final DetachedCriteria detachedCriteria){ |Mm9QF;iA
return findPageByCriteria GomTec9.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ^zMME*G
} VGVZ`|
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public PaginationSupport findPageByCriteria QB Nnvg4v
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(final DetachedCriteria detachedCriteria, finalint g@va@*|~d
0! :1o61
startIndex){ [`_ZlC
return findPageByCriteria JMUk=p<\
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(detachedCriteria, PaginationSupport.PAGESIZE, Q bg,q
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startIndex); QEavbh^S
} FuiEy=+
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public PaginationSupport findPageByCriteria scffWqEo
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(final DetachedCriteria detachedCriteria, finalint (&w'"-`
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pageSize, rT2gX^Mj&
finalint startIndex){ vSt7&ec
return(PaginationSupport) }|k_sx:
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getHibernateTemplate().execute(new HibernateCallback(){ |b@H]c;"
publicObject doInHibernate fVU9?^0/)9
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(Session session)throws HibernateException { \uumNpB*n
Criteria criteria = f?ImQYqP
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detachedCriteria.getExecutableCriteria(session); =
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int totalCount = V>{G$(v$
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((Integer) criteria.setProjection(Projections.rowCount M<A*{@4$w&
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()).uniqueResult()).intValue(); Ag>E%N
criteria.setProjection A?DgeSm
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(null); urlwn*!^s
List items = (|6Y1``
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criteria.setFirstResult(startIndex).setMaxResults v{N4*P.0T
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(pageSize).list(); T,Bu5:@#
PaginationSupport ps = [|=#~(yYQ
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new PaginationSupport(items, totalCount, pageSize, 92@/8,[
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startIndex); ;{n@hM*O
return ps; eb])=
} .HM1c
}, true); 6z/ct|n
} %{fa
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public List findAllByCriteria(final RGeM.
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DetachedCriteria detachedCriteria){ -:hiLZJ7-
return(List) getHibernateTemplate <K~> :4c
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().execute(new HibernateCallback(){
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publicObject doInHibernate ')d&:K*M
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(Session session)throws HibernateException { q(i^sE[y
Criteria criteria = SWAggW)
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detachedCriteria.getExecutableCriteria(session); "l-L-sc,
return criteria.list(); y^rcUPLT
} YF+hN\
}, true); ~*3obZ2>2
} *h<=
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public int getCountByCriteria(final V~Zi #o
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DetachedCriteria detachedCriteria){ 0!D,74r
Integer count = (Integer) L[]*vj
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getHibernateTemplate().execute(new HibernateCallback(){ u|!On
publicObject doInHibernate 0ssKZ9Lc
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(Session session)throws HibernateException { N1lhlw6
Criteria criteria = b8?qYm
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detachedCriteria.getExecutableCriteria(session); e}x}Fj</(
return r/X4Hy0!lT
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criteria.setProjection(Projections.rowCount ,0'Yj?U>
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()).uniqueResult(); K[wOK
} vv2N;/;I
}, true); y_^w|
return count.intValue(); _RLx;Tn)L
} E8TJ*ZU
} U
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用户在web层构造查询条件detachedCriteria,和可选的 ISQC{K']J
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uS9:cdH
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PaginationSupport的实例ps。 QHt;c
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ps.getItems()得到已分页好的结果集 HT]v S}s
ps.getIndexes()得到分页索引的数组 L53qQej<
ps.getTotalCount()得到总结果数 Q^^.@FU"x
ps.getStartIndex()当前分页索引 \5+?wpH
ps.getNextIndex()下一页索引 k,EI+lC X
ps.getPreviousIndex()上一页索引 {U$qxC]M
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 w#?@ulr]d
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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 TY|5O!
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一下代码重构了。 u9WQ0.
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我把原本我的做法也提供出来供大家讨论吧: _3q%
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首先,为了实现分页查询,我封装了一个Page类: KY)rkfo B
java代码: "3!!G=s P
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/*Created on 2005-4-14*/ }yCw|B|a
package org.flyware.util.page; Km~\^(a '
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/** 1B;-ea
* @author Joa *. H1m{V
* _ n.2'
*/ LPjsR=xi
publicclass Page { DVu_KT[H d
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/** imply if the page has previous page */ 9NH"Ik*
privateboolean hasPrePage; _9Pxtf
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/** imply if the page has next page */ NLe+
privateboolean hasNextPage; 'xNPy =#
b\/:-][
/** the number of every page */ tK<GU.+
privateint everyPage; < bHu9D
UWdPB2x[
/** the total page number */ @PXb^x#k
privateint totalPage; B]PTe~n^
H'Mc]zw_,
/** the number of current page */ zj!&12w%3
privateint currentPage; $#4J^(I*:
5XO eYO{
/** the begin index of the records by the current ,"U8Fgf[r
!/4f/g4Ze
query */ ?Rc+H;x=f
privateint beginIndex; !6eXJ#~[E
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/** The default constructor */ KtWG2
public Page(){ ]w _,0q
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} stnyJ9
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/** construct the page by everyPage Ol>"'
* @param everyPage ?^z!yD\
* */ oE+s8Q
public Page(int everyPage){ 2 }QD>
this.everyPage = everyPage; P) fv:a
} b\zRwp
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/** The whole constructor */ \Vis
public Page(boolean hasPrePage, boolean hasNextPage, BX[92~Bq
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int everyPage, int totalPage, gf]biE"k
int currentPage, int beginIndex){ ({3hX"C@Q
this.hasPrePage = hasPrePage; "7R"(.~>
this.hasNextPage = hasNextPage; 5YJn<XEc
this.everyPage = everyPage; 1y5]+GU'`
this.totalPage = totalPage; 0NLoqq
this.currentPage = currentPage; <BIj
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this.beginIndex = beginIndex; Vp
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} *|n::9
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/** [/#c9RA
* @return t<O5_}R%d
* Returns the beginIndex. w=I'
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*/ ;!4Bw"Gg
publicint getBeginIndex(){ p*10u@,
return beginIndex; ~Mv@Bl
} 6KiI3%y?0
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/** T ,,
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* @param beginIndex *uR&d;vg.8
* The beginIndex to set. kJ6=T6s
*/ !UE'
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publicvoid setBeginIndex(int beginIndex){ D_GIj$%N[
this.beginIndex = beginIndex; yD
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} hWK}] gF
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/** 0N3 cC4!
* @return SWr?>dl
* Returns the currentPage. Hz$l)g}U
*/ \14"B gj1
publicint getCurrentPage(){ 4[za|t
return currentPage; ;dl>
} r}OK3J
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/** 8tWOVLquJ
* @param currentPage ^(I4Do~}
* The currentPage to set. mrDIt4$D
*/ P&3'N~k-
publicvoid setCurrentPage(int currentPage){ SCk2D!u
this.currentPage = currentPage; ~U&,hFSPY
} &6A'}9Ch
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/** i<|5~tm
* @return @psyO]D=j%
* Returns the everyPage. [B9'/:
*/
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publicint getEveryPage(){ 0bxB@(NO
return everyPage; 3X$)cZQ
} .$+]N[-=
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/** I]P'wav~O
* @param everyPage E6n3[Z
* The everyPage to set. '1A S66k
*/ |p J)w
publicvoid setEveryPage(int everyPage){ &| %<=\
this.everyPage = everyPage; _[-+%RP
} IM&2SSmYNH
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/** ; >3q@9\D
* @return <v;;:RB6c
* Returns the hasNextPage. I*R[8|
*/ _aVrQ@9
publicboolean getHasNextPage(){ OaU-4
~n;
return hasNextPage; JqTkNKi/s
} &P&LjHFK
V6"<lK8"
/**
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* @param hasNextPage h+Km |
* The hasNextPage to set. 4g]Er<-P
*/ ?Y2ZqI
publicvoid setHasNextPage(boolean hasNextPage){ ~vnG^y>%
this.hasNextPage = hasNextPage; e2Sm.H '
} LtKiJ.j?A
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/** D.o|pTZ
* @return }f np}L
* Returns the hasPrePage. trmCIk&Fkj
*/ lk{
publicboolean getHasPrePage(){ XnrOC|P$
return hasPrePage; D/jB.
} G?!b00H
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/** c%v[p8
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* @param hasPrePage fk4s19;?
* The hasPrePage to set. IbC(/i#%`
*/ egboLqn
publicvoid setHasPrePage(boolean hasPrePage){ @\v,
this.hasPrePage = hasPrePage; /2-S/,a
} v!?bEM3D
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/** R*IO%9O
* @return Returns the totalPage. Qj~m;F!
* mdvooJ
*/ 8R Wfv}:X
publicint getTotalPage(){ GwxxW
return totalPage; |cStN[97%
} }$3eRu +
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/** #k8bZ?*:
* @param totalPage C4],7"Sw
* The totalPage to set. BL<.u
*/ Pcut#8?
publicvoid setTotalPage(int totalPage){ C{!L +]/
this.totalPage = totalPage; /%|JP{
} r(iT&uz
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} 4>nY't;0
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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 Htn=h~U`z
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个PageUtil,负责对Page对象进行构造: !/+ZKx("9
java代码: o9ZHa
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/*Created on 2005-4-14*/ \#.,@g
package org.flyware.util.page; ;LE4U OK
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import org.apache.commons.logging.Log; q65KxOf`
import org.apache.commons.logging.LogFactory; aAZS^S4v
r=P)iE:
/** l
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* @author Joa r2}u\U4>
* =; Gw=m(
*/ 9Z]~c^UB
publicclass PageUtil { o&P}GcEIw
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privatestaticfinal Log logger = LogFactory.getLog n/#zx:d?
3ny>5A!;2
(PageUtil.class); &Oc^LV$6
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/** bVmHUcR0
* Use the origin page to create a new page ZC 7R f
* @param page S[,!
* @param totalRecords ^;jJVYx-PP
* @return ^T@ (`H4@
*/ bh|M]*Pq
publicstatic Page createPage(Page page, int ehk5U,d
vN:gu\^-
totalRecords){ 8uq^Q4SU
return createPage(page.getEveryPage(), >Jh*S`e
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page.getCurrentPage(), totalRecords); {Vw+~8
} CsHHJgx
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/** Qb<i,`SN
* the basic page utils not including exception Qd;P?W6
a5=8zO#%g
handler W_l/Jpv!W
* @param everyPage xY9#ouF
* @param currentPage Fb=(FQ2Y?
* @param totalRecords k#Qav1_
* @return page bA}9He1
*/ 4-;"w;
publicstatic Page createPage(int everyPage, int {Q],rv|;
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currentPage, int totalRecords){ sC
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everyPage = getEveryPage(everyPage); [ZC]O2'
currentPage = getCurrentPage(currentPage); ir/m.~?
int beginIndex = getBeginIndex(everyPage, -F=?M+9[
)!.ef6|
currentPage); rD=8O#m
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int totalPage = getTotalPage(everyPage, WLl_;BgN
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totalRecords); i!g}PbC[
boolean hasNextPage = hasNextPage(currentPage, r09gB#K4
873$EiyXR
totalPage); ]j> W9n?
boolean hasPrePage = hasPrePage(currentPage); hkV;(Fr&z
{hQ0=rv<
returnnew Page(hasPrePage, hasNextPage, S:)Aj6>6
everyPage, totalPage, ]D?//
currentPage, ta"uxL\gge
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beginIndex); ~hK7(K
} Aq'yr,
zh`!x{Z?^
privatestaticint getEveryPage(int everyPage){ 8:=&=9%
return everyPage == 0 ? 10 : everyPage; p F kA,
} mdjPKrF<
&*2\1;1tB
privatestaticint getCurrentPage(int currentPage){ biAI*t
return currentPage == 0 ? 1 : currentPage; AsFn%8_I
} _CqVH5U?
_8t5rF
privatestaticint getBeginIndex(int everyPage, int I5]=\k($
1o"/5T:S[
currentPage){ K$v
SdpC
return(currentPage - 1) * everyPage; rEz-\jLD~
} +8qtFog$\g
o6`4y^Q{/
privatestaticint getTotalPage(int everyPage, int c%1k'Q
@}[ >*Xy%
totalRecords){ Mx9#YJ?t~
int totalPage = 0; PWeCk2 xH
sF9{(Us
if(totalRecords % everyPage == 0) +&hhj~I.
totalPage = totalRecords / everyPage; cUW>`F(S
else _)|_KQQu
totalPage = totalRecords / everyPage + 1 ; BGM5pc (ei
.*XELP=BT
return totalPage; EUBJnf:q
} CTawXHM
WP7RX|7
privatestaticboolean hasPrePage(int currentPage){ eu=G[>
return currentPage == 1 ? false : true; :"m~tU3&
} (w4w
y8} fj=
privatestaticboolean hasNextPage(int currentPage, 7$3R}=Z`\q
S1jI8 #z}_
int totalPage){ m(0sG(A~
return currentPage == totalPage || totalPage == 4I7B
#{
\s_lB~"P!3
0 ? false : true; rJLn=|uR
} F`!B!uY
J|*Z*m
-s~6FrKy
} y?=W
$ti*I;)h4
U'(Exr[
L{`S^'P<
5mzOr4*0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Xge]3Ub
=BD} +(3
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 %=p:\+`VI
s
P=$>@3
做法如下: Y~I$goT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 GMk\
l
_#[~?g`
的信息,和一个结果集List: 5\\#kjjx
java代码: mjgwU8'![
7D'-^#S5
/#mq*kNIM6
/*Created on 2005-6-13*/ mCM7FFl I
package com.adt.bo; b1+6I_u.
H~Z$ pk%
import java.util.List; qY,z,oAF
b\6)whh
import org.flyware.util.page.Page; . <xzf4C
&[u>^VO8
/** 3[q&%Z.
* @author Joa 0cYd6u@
*/ s*'L^>iZ
publicclass Result { ~kDR9s7
|gXtP-
private Page page; eZ>KA+C[
MmIVTf4
private List content; ^b{ -y
Kmy'z
/** P9d%80(b4
* The default constructor mM`zA%=
*/ n oWjZ
public Result(){ }E
o\=>l7
super(); PK&3nXF%4
} ]JGh[B1gh
FEOr'H<3x
/** L >*
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* The constructor using fields +SM&_b
* 9gu$vF]9!
* @param page w$5~'Cbi
* @param content j[E8C$lW
*/ [cJQ"G '
public Result(Page page, List content){ %62W[Oh5
this.page = page; $O\I9CGr$
this.content = content; >Xz=E0;^Ua
} ? PIq/[tk
hMcSB8 ?
/** WUC-*(
* @return Returns the content. 'eM90I%(
*/ t1LIZ5JY
publicList getContent(){ =1!,A
return content; \VL_
} `/|S.a#g
M<Gr~RKmAn
/** V)pn)no'V
* @return Returns the page. #sHA!@ |
*/ m7~<z>5$
public Page getPage(){ 0LX"<~3j
return page; Sn o7Ru2
} /6?A#%hc
,s=jtK
/** gzHMZ/31
* @param content @M]uUL-ze
* The content to set. $ 12mS
*/ D)kh"cK*1
public void setContent(List content){ B/:+(|
this.content = content; %_kXC~hH_
} j|6@>T1
6}V)\"u&
/** 4=;.<
* @param page XwZ~pY ~
* The page to set. WO}l&Q
*/ '
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publicvoid setPage(Page page){ \>B$x@-wg
this.page = page; t^8ii
} Nu/D$m'PY
} o+NPe36
73n|G/9n[
|iGfX,C|
xgdS]Sz
i146@<\G{P
2. 编写业务逻辑接口,并实现它(UserManager, L9lN AiOH
|*G$ilu
UserManagerImpl) dz3KBiq
java代码: ?MW*`U
9+z5$
RFsd/K; Zp
/*Created on 2005-7-15*/ [RAzKzC\M
package com.adt.service; Fi7G S;
'zRi;:UHA
import net.sf.hibernate.HibernateException; %i!=.7o.
.Lwp`{F/
import org.flyware.util.page.Page; jY~W*
|JUb 1|gi
import com.adt.bo.Result; :Dh\
^)JUl!5j]C
/** @ij8AGE:
* @author Joa oVD)Fb%[i9
*/ sIVVF#0}]
publicinterface UserManager { Q140b;Z
Sckt gp8
public Result listUser(Page page)throws =up!lg^M
\d"uR@$3mG
HibernateException; T[~8u9/
A#b`{C~l
} *btLd7c%
Q|gw\.]$&[
$uPM.mPFE
g':/hlQ
(f-Mm0%[
java代码: `:aml+
CMcS4X9/}
34D7qR
/*Created on 2005-7-15*/ [!g$|
package com.adt.service.impl; iXF iFsb
6w? l
I
import java.util.List; +qWrm|O]
~PTqR2x
import net.sf.hibernate.HibernateException; gv6}GE
Zb \E!>V
import org.flyware.util.page.Page; IIZu&iZo\
import org.flyware.util.page.PageUtil; wsfN \6e
zL^`r)H
import com.adt.bo.Result; _mEW]9Sp
import com.adt.dao.UserDAO; he
vM'"|4
import com.adt.exception.ObjectNotFoundException; hJ)\Vo
import com.adt.service.UserManager; 7EfLd+
JU6PBY~C'
/** {vp|f~}zTw
* @author Joa _,"?R]MO
*/ )335X wA+
publicclass UserManagerImpl implements UserManager { }L!%^siG_
vp[;rDsIJ$
private UserDAO userDAO; (O[:-Aqm
`rwzCwA1
/** %(P\"hE'
* @param userDAO The userDAO to set. 6'F4p1VG*I
*/ #4yh-D"
publicvoid setUserDAO(UserDAO userDAO){ >`0l"K<
this.userDAO = userDAO; :2Fy`PPab
} Iu)76Y@=5=
M%3P@GRg
/* (non-Javadoc) i[+cNJ|$B0
* @see com.adt.service.UserManager#listUser A89n^@
#"T< mM7
(org.flyware.util.page.Page) Ej[:!L
*/
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public Result listUser(Page page)throws 1#Ls4+]5
Pse1NMK9 [
HibernateException, ObjectNotFoundException { 7])cu>/
int totalRecords = userDAO.getUserCount(); J2KULXF
if(totalRecords == 0) lI)RaiMr=
throw new ObjectNotFoundException pv}k=wqJ1
b|rMmx8vA
("userNotExist"); dj;Zzt3
page = PageUtil.createPage(page, totalRecords); &'mq).I2
List users = userDAO.getUserByPage(page); eG@0:
returnnew Result(page, users); !{WIN%O
} 342m=7lK
AZHZUd4
} hoLQuh%2%
34Fc
oud);
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eZck$]P(6H
|riP*b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fr19C%{
Miw*L;u@W
询,接下来编写UserDAO的代码: xn&$qLB
3. UserDAO 和 UserDAOImpl: ask76
e
java代码: x!i(M>P
NCXr$ES{
2w7PwNb*32
/*Created on 2005-7-15*/ DHnO ,"
package com.adt.dao; ^&Exa6=*FT
+H4H$H
import java.util.List; N Dqvt$
j "^V?e5
import org.flyware.util.page.Page; 2!Gb4V
AeZ__X
import net.sf.hibernate.HibernateException; /uNgftj
y8!#G-d5
/** lQq&tz,
* @author Joa Eq\PSa=gz
*/ 3=
q,k<=L
publicinterface UserDAO extends BaseDAO { J8;l G
J^Mq4&
publicList getUserByName(String name)throws v90)G8|q
jG E=7
HibernateException; {\P`-'C
IQm[,Fh
publicint getUserCount()throws HibernateException; Twi7g3}/jB
P@xb
publicList getUserByPage(Page page)throws \\D(St
A><q-`bw
HibernateException; 6F)^8s02h
$GI
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} zZhA]J
c97?+Y^
YWK|AT-4
2X)n.%4g$;
;/79tlwq
java代码: X9S`#N
2d:5~fEJp
G%q^8#
/*Created on 2005-7-15*/ BPwn!ii|
package com.adt.dao.impl; <aPbKDF~V
nRSiW*;R
import java.util.List; kLfk2A;' i
+%'!+r
l
import org.flyware.util.page.Page; &|
guPZ
A#@9|3
import net.sf.hibernate.HibernateException; ' ~F
import net.sf.hibernate.Query; e{}oQK
)<+t#5"
import com.adt.dao.UserDAO; d OYEl<!J
)[]*Y]vSx
/** `alQmGUZ
* @author Joa :MF F*1
*/ vTk\6o q
public class UserDAOImpl extends BaseDAOHibernateImpl {~y,.[Ga
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implements UserDAO { cN&]JS,
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/* (non-Javadoc) {: H&2iF
* @see com.adt.dao.UserDAO#getUserByName ~rl,Hr3Zo
4[P]+Z5b+
(java.lang.String) j]X$7
*/ qtI42u{
publicList getUserByName(String name)throws )/vse5EG+
1OOMqFn} L
HibernateException { er44s^$
String querySentence = "FROM user in class ToXgl4:kd
!VoAN5#;
com.adt.po.User WHERE user.name=:name"; ;J&p17~T9
Query query = getSession().createQuery #=81`u
EG&97lb
(querySentence); )/{zTg8$?/
query.setParameter("name", name); p "Cxe
return query.list(); R?E< }\!
} Xk]:]pl4W
}QzF.![~z
/* (non-Javadoc) Q/2(qD; u
* @see com.adt.dao.UserDAO#getUserCount() -KA Y
*/ "pa2,-&
publicint getUserCount()throws HibernateException { i
.GJO +K
int count = 0; 1I#]OY#>
String querySentence = "SELECT count(*) FROM AW')*{/(Ii
Fo: 60)Lr
user in class com.adt.po.User"; `v"p""_H
Query query = getSession().createQuery 5IJm_oy
*]#(?W.$w
(querySentence); }Tz<fd/
count = ((Integer)query.iterate().next >DSD1i+N
d&x #9ka
()).intValue(); 5?=haGn
return count; a^xt9o`
} Gtm|aR{OS
%={[e`,
/* (non-Javadoc) 6VQe?oh
* @see com.adt.dao.UserDAO#getUserByPage z:p;Wm
M}Obvl
(org.flyware.util.page.Page) )&F]j
*/ HVLj(_
A
publicList getUserByPage(Page page)throws W3M1> (
5B)z}g^h
HibernateException { a@v}j&
String querySentence = "FROM user in class
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,"xr^@W
com.adt.po.User"; \|f3\4;!
Query query = getSession().createQuery $eU oFa5A
5BAGIO<w
(querySentence); j0q:i}/U,
query.setFirstResult(page.getBeginIndex()) =Y]'wb
.setMaxResults(page.getEveryPage()); ,3P@5Ef
return query.list(); S9mcThcZ
} s)BB(vQ]6
sn.0`Stt
} q?0&&"T}
=&,<Co1 hF
+aoenUm5
qdQQt5Y'm
];
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至此,一个完整的分页程序完成。前台的只需要调用 <oKoz0!
8ZN"-]*
userManager.listUser(page)即可得到一个Page对象和结果集对象 oQL$X3S
sgfci{~
的综合体,而传入的参数page对象则可以由前台传入,如果用 WFm\ bZ.
=#so[Pd
webwork,甚至可以直接在配置文件中指定。 LLD#)Jl{?
:v
Do{My^1
下面给出一个webwork调用示例: xN +Oca
java代码: 3[r9v!l
Ej#pM.
|?\J,h
/*Created on 2005-6-17*/ 'i;/?'!W6
package com.adt.action.user; rUxjm\
3k_bhK zI
import java.util.List; s,|"s|P
Tg yY 9
import org.apache.commons.logging.Log; KSgYf;
import org.apache.commons.logging.LogFactory; (`)ZR%i
import org.flyware.util.page.Page; S-2@:E
>[r ,X$]
import com.adt.bo.Result; n1
import com.adt.service.UserService; Usl963A#'F
import com.opensymphony.xwork.Action; A3s-C+@X
HS@ EV iht
/** E(p#Je|@[
* @author Joa 0@LC8Bz+'
*/ e jh0Wfl
publicclass ListUser implementsAction{ X"EZpJ'W
IY40d^x
privatestaticfinal Log logger = LogFactory.getLog ~m6b6Aj@6
ttd
^jT
(ListUser.class); #gc v])to
\u$[ $R5
private UserService userService; FnWN]9
M;j)F
private Page page; ]rS:#LK
uFYcVvbT@
privateList users; i1JVvNMQ,
0?Bv
zfb
/* >)*0lfxTZ
* (non-Javadoc) ]WvV*FL9D3
* S>;+zVF]
* @see com.opensymphony.xwork.Action#execute() >XJUj4B|X
*/ BIY"{"hJ
publicString execute()throwsException{ `_+%
Result result = userService.listUser(page); pQCocy
page = result.getPage(); PR3&LI;B*
users = result.getContent(); 4'#?"I
return SUCCESS; OVUJiBp
} vJ9IDc|[
/I48jO^2
/** {JlSfJw!
* @return Returns the page. qtlcY8!
*/ sIzy/W0iV
public Page getPage(){ M{4U%lk
return page; b<27XZ@
} a&!K5(
m"f3hd4D_q
/** .r~M7 I
* @return Returns the users. 3,^.
*/ ngOGo =
publicList getUsers(){ l}_6_g>6
return users; oxNQNJ!X
} bc]SY =
=:*2t
/** _V,bvHWlM
* @param page \\P*w$c
* The page to set. :k Kdda<g#
*/ @MKf$O4K
publicvoid setPage(Page page){ a)QSq<2*
this.page = page; zGtv(gwk
} ht_'GBS)
:$Xvq-#$|
/** '1"vwXJ"
* @param users v(P5)R,
* The users to set. @kW RI* m
*/ z#*>u
publicvoid setUsers(List users){ KD`*[.tT
this.users = users; R q`j|tY
} Mhu|S)hn
'0<9+A#
/** Sf'uKSX1%
* @param userService D}~uxw;[^
* The userService to set. UIC~%?oIA
*/ q$'D}OH T
publicvoid setUserService(UserService userService){ Eg(.L,dj
this.userService = userService; 6PT"9vR`)
} 0y`r.)G
} 9@>Q7AUCQ
nLY(%):(P
zALtG<_t
x7!gmbMfK'
Ejj+%)n.
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, QxT\_Nej*n
oVQbc\P3
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 )Wy:I_F351
|#ZMZmo{
么只需要: 'x<o{Hi"\B
java代码: (W
|;gQ
.'bhRQY
J1Run0
<?xml version="1.0"?> @_0tq {
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork H;MyT Vl
`r]C%Y4?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- =Q #d0Q
Ff1!+P,
1.0.dtd"> D"CU J?
elz0t<V
<xwork> ,</Kn~b
Zp/$:ny
<package name="user" extends="webwork- 3z% W5[E)
`(M0I!t
interceptors"> 0i(c XB
^s\T<;
<!-- The default interceptor stack name -tA_"q'^
Mc{-2
--> z) x.6
<default-interceptor-ref XD Q<28^
;KgDVq5
name="myDefaultWebStack"/> G7%f|
Y
~\+Bb8+hpJ
<action name="listUser" dOVu D(
9V|)3GF
class="com.adt.action.user.ListUser"> @H$Sv
<param PR7B
Cxm
sh*/wM
name="page.everyPage">10</param> kS4YxtvB
<result r@EHn[w
x/ix%!8J
name="success">/user/user_list.jsp</result> .Nk5W%7]=
</action> 1Gy
[^
B Q2N_*v
</package>
N@X(YlO
K[S)e!\.
</xwork> &WZ&Tt/)/
z"-oD*ICw
PYTwyqS
;;+h4O )
og&-P=4O
zUq(bD
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 Qna*K7kv
fr`Q
5!0
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。 gv){&=9/
_&r19pY
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 AdRp{^w
xnHB
<xrE}
5\}E4y
g3
Oro}wt6
={;7WB$
我写的一个用于分页的类,用了泛型了,hoho QD-`jV3
Lngf,Of.e
java代码: dDa&:L
QH_Ds,oH=
v#?;PyeF
package com.intokr.util; dZX;k0
'Y/kF1,*
import java.util.List; &Q* 7
}WhRJr`a
/** wVs"+4l<
* 用于分页的类<br> _bt9{@)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ]Y@_ 2`
* >+DMTV[O
* @version 0.01 \BX9Wn*)a
* @author cheng _l2_) ~
*/ [^D>xD3B2
public class Paginator<E> { L1f=90
privateint count = 0; // 总记录数 bu-6}T+
privateint p = 1; // 页编号 {< EPm&q
privateint num = 20; // 每页的记录数 O[\mPFu5
privateList<E> results = null; // 结果 #8~ygEa}
KTBtLUH]*F
/** 9bhubx\^/
* 结果总数 (\o4 c0UzK
*/ @$iZ9x6t
publicint getCount(){ CDoD9Hq,
return count; 0f@9y
} 6)BPDfU,
o2cc3`*8d
publicvoid setCount(int count){ 7!wc'~;
this.count = count; P- +]4\
} R x( yn
;G[0%z+*
/** ;WAa4r>
* 本结果所在的页码,从1开始 4I .'./u
* EwmNgmYq
* @return Returns the pageNo. I9m9`4BK
*/ }9glr]=
publicint getP(){ /;{L~f=et)
return p; jT!?lqr(Rb
} %hlgLM
sVGQSJJ5
/** yFS{8yrRUU
* if(p<=0) p=1 }Q@~_3,UJ
* "n)AlAV@
* @param p =:!>0~
*/ }h1eB~6M
publicvoid setP(int p){ bYZU}Kl;(
if(p <= 0) _#MKp H
p = 1; /DP0K
@%
this.p = p; 8_o~0lb
} |5ge4,}0
i=1crJ:
/** EJRkFn8XG'
* 每页记录数量 Ke=+D'=
*/ 6kMkFZ}+
publicint getNum(){ \
\Tz'>[\
return num; D[}^G5
} t&NpC;>v
RWX!d54&
/** :H&G}T(#
* if(num<1) num=1 a>rDJw:
*/ &W c$VDC
publicvoid setNum(int num){ !|j|rYi-
if(num < 1) ><>%;HZ
num = 1; \ q3ui}-9
this.num = num; *A4eYHn@
} [S8*b^t4
MT:VQ>fC
/** T\(k=0RM
* 获得总页数 ,I ][
*/ >]&Ow9-
publicint getPageNum(){ u~2]$ /U
return(count - 1) / num + 1; :Ocw+X3
} [~X&J#
.gzfaxi
/** $zU%?[J
* 获得本页的开始编号,为 (p-1)*num+1 e$2P/6k>
*/ O1)\!=&
.
publicint getStart(){ T,jb%uPcE
return(p - 1) * num + 1; rZcSG(d`53
} tbiM>qxB
mQR9Pn}H
/** }S3 oX$
* @return Returns the results. F#M(#!)Y"
*/ RgL>0s
publicList<E> getResults(){ +
d 3
return results; pT3icy!A=
} $45.*>,
V0#Ocq,
public void setResults(List<E> results){ (>f`>6 V
this.results = results; eG8l^[
} U djYRfk
Dte5g),R
public String toString(){ HyOrAv
<
StringBuilder buff = new StringBuilder UqyW8TCf?
q mv0 LU
(); $COjC!M
buff.append("{"); \v5;t9uBZ
buff.append("count:").append(count); c#"t.j<E}
buff.append(",p:").append(p); zH6@v+gb
buff.append(",nump:").append(num); 2%6 >)|
buff.append(",results:").append {7c'%e
F?05+
(results); #p55/54ZI
buff.append("}"); iU37LODa2T
return buff.toString(); M8<Vd1-5
} J=gFiBw
>C!^%e;m
} @SpP"/)JY
|2@*?o"ll
; :q