Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 hN6wp_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H~nX!sO
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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 9N'fU),I
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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 p|2GPrA]aL
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分页支持类: \
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java代码: (w)%2vZ^
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package com.javaeye.common.util; Wn+s:ov
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import java.util.List; jaodcT0
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publicclass PaginationSupport { "WQ6[;&V
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publicfinalstaticint PAGESIZE = 30; t-KicLr
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privateint pageSize = PAGESIZE; .,xyE--;d
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privateList items; x4c|/}\)*
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privateint totalCount; pXO09L/nv
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privateint[] indexes = newint[0]; $M,<=.oT
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privateint startIndex = 0; go AV+V7
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public PaginationSupport(List items, int
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totalCount){ 3=sBe HL
setPageSize(PAGESIZE); k+-?b(z)$
setTotalCount(totalCount); %'s_=r`
setItems(items); CO@G%1#
setStartIndex(0); YZ+G7D>
} 7`J2/(
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public PaginationSupport(List items, int )~=8Ssu
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totalCount, int startIndex){ 2K};-}eW
setPageSize(PAGESIZE); <hCO-r#
setTotalCount(totalCount); Vf pT5W<
setItems(items); r/'!#7dLG-
setStartIndex(startIndex); |{kbc0*
} lr~
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public PaginationSupport(List items, int 4x[_lsj
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totalCount, int pageSize, int startIndex){ yjL+1_"B
setPageSize(pageSize); ?SFQx\/
setTotalCount(totalCount); j
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setItems(items); 06^/zr
setStartIndex(startIndex); z6@8IszU
} [?I<$f"
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publicList getItems(){ OS@uGp=
return items; Z3{1`"\<K
} 8bdO-LJ9
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publicvoid setItems(List items){ 0}NDi|o
this.items = items; hxMRmH[f:
} .cJoNl'q
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publicint getPageSize(){ %_5#2a
return pageSize; B;(U?gC
} 1Y $%| `
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publicvoid setPageSize(int pageSize){ U&BCd$
this.pageSize = pageSize; 07:V[@'
} ~M^[
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publicint getTotalCount(){ WyatHC
return totalCount; ?K7uy5Y
} r6uN6XCM
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publicvoid setTotalCount(int totalCount){ qH4|k2Lm
if(totalCount > 0){ g&y (-
this.totalCount = totalCount; <A Hzs
int count = totalCount / R;Dj70g
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pageSize; Wjl2S+Cc
if(totalCount % pageSize > 0) v[ML=pL
count++; 4Z%1eOR9V
indexes = newint[count]; /A,w{09G
for(int i = 0; i < count; i++){ .
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indexes = pageSize * rN|=cn
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i; $aJ6i7C,j}
} L$_%T
}else{ 3f^Pr
this.totalCount = 0; \h=*pAf
} \OkZ\!<hg
} |E?r+]
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publicint[] getIndexes(){ Y|r7gy9%
return indexes; 1!.-/
} d"Zu10
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publicvoid setIndexes(int[] indexes){ kVWcf-f
this.indexes = indexes; H5Eso*v@
} ZN)EbTpc\a
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publicint getStartIndex(){ e&ysj:W5
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return startIndex; *`"+J_
} #'1dCh
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publicvoid setStartIndex(int startIndex){ _?O' A"
if(totalCount <= 0) LJ
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this.startIndex = 0; gQ0,KYmI3_
elseif(startIndex >= totalCount) 3,q?WH%_
this.startIndex = indexes eg/itty
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[indexes.length - 1]; v}u]tl$,
elseif(startIndex < 0) =>5Lp
this.startIndex = 0; ^7+;XUyg
else{ fdKE1,;
this.startIndex = indexes +_fFRyu>
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[startIndex / pageSize]; }~zDcj_
} )/'WboL
} td7(444]
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publicint getNextIndex(){ P
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int nextIndex = getStartIndex() + w~v6=^
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pageSize; Jyg1z,B <
if(nextIndex >= totalCount) ?SgFD4<~P
return getStartIndex(); aXj
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else fB9,#
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return nextIndex; J'
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} xP'0a
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publicint getPreviousIndex(){ YSGE@
int previousIndex = getStartIndex() - hQx*#:ns
+'gO%^{l
pageSize; BkB_?^Nv8
if(previousIndex < 0) M}[Q2v\
return0; _f@,)n
else 6agG*x
return previousIndex; 8a8a:d
} k@lJ8(i^qU
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} 18NnXqe-m
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抽象业务类 J8S$YRZ_
java代码: T2Z$*;,>T
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/** dj(&"P
* Created on 2005-7-12 -(TC'
*/ .TA)|df
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package com.javaeye.common.business; El9T>!Z
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import java.io.Serializable; .Xp,|T
import java.util.List; ZPw4S2yw3.
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import org.hibernate.Criteria; WMC^G2 n
import org.hibernate.HibernateException; 3G4WKg.^
import org.hibernate.Session; 1W>/4l
import org.hibernate.criterion.DetachedCriteria; h?dSn:Y\?
import org.hibernate.criterion.Projections; j}.gK6Yq*
import Uzvd*>mv
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org.springframework.orm.hibernate3.HibernateCallback; j;}-x1R
import %!Eh9C*
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org.springframework.orm.hibernate3.support.HibernateDaoS ZVH 9je
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upport; Xk|a%%O*H
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import com.javaeye.common.util.PaginationSupport; Wtu-g**KN
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public abstract class AbstractManager extends TW&s c9
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HibernateDaoSupport { 2H$](k?
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privateboolean cacheQueries = false; DDmC3
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privateString queryCacheRegion; HqV55o5f'
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publicvoid setCacheQueries(boolean vT{(7m!Ra
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cacheQueries){ no-";{c
this.cacheQueries = cacheQueries; 6
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} [7.Num_L
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publicvoid setQueryCacheRegion(String 4`l$0m@>
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queryCacheRegion){ b~fl,(sZp
this.queryCacheRegion = <#BK(W~$
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queryCacheRegion; YvG$2F |_)
} r>8`gAhx
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publicvoid save(finalObject entity){ oO[eer_S-
getHibernateTemplate().save(entity); qmpT G:+
} AoGpM,W]5
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publicvoid persist(finalObject entity){ _)vX_gCi
getHibernateTemplate().save(entity); KF
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} NaoOgZ?
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publicvoid update(finalObject entity){ V#,|#2otZ
getHibernateTemplate().update(entity); , Zie2I?q
} *j83E[(]
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publicvoid delete(finalObject entity){ 4IZAJqw(*
getHibernateTemplate().delete(entity); _s#J\!F
} WVQHb3Pe0
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publicObject load(finalClass entity, A
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finalSerializable id){ %fld<O
return getHibernateTemplate().load _gK}Gi?|
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(entity, id); -{*3<2rFK
} ]+ub
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publicObject get(finalClass entity, BIMX2.S1o
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finalSerializable id){ $ H@
return getHibernateTemplate().get oAN,_1v)
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(entity, id); EK>x\]O%T
} `>KNa"b%$
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publicList findAll(finalClass entity){ T)22P<M8
return getHibernateTemplate().find("from FB?V<x
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" + entity.getName()); V
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} z I9jxwXU
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publicList findByNamedQuery(finalString =1>G*
,
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namedQuery){ bp8sZK"z
return getHibernateTemplate dh{py
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().findByNamedQuery(namedQuery); /C`AA/@
} ByoI+n* U
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publicList findByNamedQuery(finalString query, se3EI1e
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finalObject parameter){ y<IHZq`C3
return getHibernateTemplate L6qK3xa}
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().findByNamedQuery(query, parameter); E}w5.1
} ;gHcDnH)
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publicList findByNamedQuery(finalString query, Qj
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finalObject[] parameters){ v^/<2/E"?4
return getHibernateTemplate 4Z{R36 {
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().findByNamedQuery(query, parameters); , =*^XlO=c
} 7dB_q}<
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publicList find(finalString query){ WB (?6"
return getHibernateTemplate().find "<^
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(query); Qe7
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} o^uh3,.
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publicList find(finalString query, finalObject h+q#|N
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parameter){ Wvd-be
return getHibernateTemplate().find !:vQg+S
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(query, parameter); gi:M=
} 5B1,,8P
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public PaginationSupport findPageByCriteria @!x7jPr
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(final DetachedCriteria detachedCriteria){ A&KY7[<AC{
return findPageByCriteria 9l&G2 o
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); S:2 xm8
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} H`3w=T+I
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public PaginationSupport findPageByCriteria .;vd
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(final DetachedCriteria detachedCriteria, finalint N1n\tA?
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startIndex){ /f.
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return findPageByCriteria f~jdN~
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(detachedCriteria, PaginationSupport.PAGESIZE, 3!?QQT,!)
x )q$.u+
startIndex); ~Wm'~y>
} E/% F0\B
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public PaginationSupport findPageByCriteria Br$/hn=
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(final DetachedCriteria detachedCriteria, finalint v<0S@9~
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pageSize, nu|?F\o!
finalint startIndex){ >NpW$P{'
return(PaginationSupport) HW6Cz>WxOW
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getHibernateTemplate().execute(new HibernateCallback(){ 0eCjK.
publicObject doInHibernate v!mP9c
j
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(Session session)throws HibernateException { X5tV Xd
Criteria criteria = lvk*Db$
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detachedCriteria.getExecutableCriteria(session); -x/g+T-
int totalCount = M
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Z\?!&&
((Integer) criteria.setProjection(Projections.rowCount ryd}-_LL
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()).uniqueResult()).intValue(); ybB<AkYc
criteria.setProjection d?CU+=A&|
DEv,!8
(null); _B ]Bd@<w
List items = 3
}rx(
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criteria.setFirstResult(startIndex).setMaxResults 4x/u$Ixzh=
`UkjrMO
(pageSize).list(); &)~LGWBdC
PaginationSupport ps = xA}{ZnTbN
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new PaginationSupport(items, totalCount, pageSize,
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startIndex); 8wS9%+
return ps; Ujly\ix`
} okW'}@jD
}, true); Pb :6nH=
} \ItAc2,Fl
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public List findAllByCriteria(final ~#zb
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DetachedCriteria detachedCriteria){ 0ENqK2
return(List) getHibernateTemplate A kqGk5e
^
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().execute(new HibernateCallback(){ AqrK==0N
publicObject doInHibernate 0*u X2*
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(Session session)throws HibernateException { l)0yv2[h
Criteria criteria = Xb*>7U/'T
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detachedCriteria.getExecutableCriteria(session); %x$mAOUv
return criteria.list(); 0I.!
} 'VY\ut
}, true); ]"1\z>Hg
} "w{,ndZ
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public int getCountByCriteria(final ~U4;YlQP
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DetachedCriteria detachedCriteria){ DZ;2aH
Integer count = (Integer) (WS<6j[q
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getHibernateTemplate().execute(new HibernateCallback(){ -(.\> F
publicObject doInHibernate -_Iuvw
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(Session session)throws HibernateException { tgm(tDL
Criteria criteria = ]GHx<5Q:\
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detachedCriteria.getExecutableCriteria(session); SB!m&;Tb
return ok9G 9|HA
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criteria.setProjection(Projections.rowCount QnDLSMx)
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()).uniqueResult();
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} CW#$%
}, true); X7"hTD
return count.intValue(); |a[ :L
} e?b<-rL
} $L$GI~w/
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用户在web层构造查询条件detachedCriteria,和可选的 i(>v~T,(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 z15QFVm
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PaginationSupport的实例ps。 ZZl4|
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ps.getItems()得到已分页好的结果集 h!>NS ?X7
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 ./;*LD
ps.getStartIndex()当前分页索引 -Qco4>Z 8
ps.getNextIndex()下一页索引 Pi|oO-M
ps.getPreviousIndex()上一页索引 =!Y{Mz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ycx$CUC
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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 D+
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一下代码重构了。 ETVT.R8
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我把原本我的做法也提供出来供大家讨论吧: S\UM0G}v
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首先,为了实现分页查询,我封装了一个Page类: I2=Kq{
java代码: R OQIw
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/*Created on 2005-4-14*/ KPA5 X]
package org.flyware.util.page; MXhRnVz"W
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/** {N,w5!cP
* @author Joa uy;3s=03^
* D r $N{d
*/ 5OUe|mS
publicclass Page { 7e"(]NC84
uNY]%[AnJ
/** imply if the page has previous page */ ]H[FZY
privateboolean hasPrePage;
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8)k.lPoo.
/** imply if the page has next page */ #B)`dA0a
privateboolean hasNextPage; tgYIM`f
:PaFC{O)*
/** the number of every page */ O_PC/=m1@
privateint everyPage; $mOK|=tI_
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/** the total page number */ {:enoV"
privateint totalPage; 6A/|XwfE/v
K~WwV8c9;
/** the number of current page */ Ja#idF[V
privateint currentPage; Z
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/** the begin index of the records by the current (Qq$ql27
Q\:'gx8`
query */ {w^flizY
privateint beginIndex; h OboM3_
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/** The default constructor */ (<.1o_Q-LU
public Page(){ +T^m
WiviH#hF
} Ahq^dx#o
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/** construct the page by everyPage I/)dXk~
* @param everyPage /HDX[R
* */ pp[? k}@
public Page(int everyPage){ m|"MJ P
this.everyPage = everyPage; *qBMt[a
} D_9/|:N:
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/** The whole constructor */ >)pwmIn<
public Page(boolean hasPrePage, boolean hasNextPage, Gz@%UIv
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int everyPage, int totalPage, M3F8@|2
int currentPage, int beginIndex){ a<gzI
this.hasPrePage = hasPrePage; n(f&uV_):
this.hasNextPage = hasNextPage; a3lo;Cfp
this.everyPage = everyPage; HKcipDW
this.totalPage = totalPage; xHr
this.currentPage = currentPage; h=4{.EegG&
this.beginIndex = beginIndex; 9Jk(ID'c
} v @N8v
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/** t8)Fkx#8}
* @return {fN_itn
* Returns the beginIndex. iy: ;g
*/ Y9w=[[1
publicint getBeginIndex(){ m&A/IW,.
return beginIndex; |k+&weuY
} T8hQ< \g
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/** E>6zwp
* @param beginIndex 4
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* The beginIndex to set. kh,M'XbTo
*/ w6"LHy[
publicvoid setBeginIndex(int beginIndex){ W'0wT ZG
this.beginIndex = beginIndex; oC[wYUDg
} Yu1xJgl
:6M0`V;L
/** v}Aw!Dv/
* @return G+g`=7
* Returns the currentPage. Ixec]UOS
*/ }5] s+m
publicint getCurrentPage(){ .D>lv_kp
return currentPage; 'FUPv61()
} =k/n
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/** =0]Mc$Ih
* @param currentPage 2.lnT{
* The currentPage to set. F9+d7 Y$
*/ vo(?[[
publicvoid setCurrentPage(int currentPage){ X)&Z{ V>
this.currentPage = currentPage; wRiP 5U,
} iN{TTy
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/** r?+u}uH
* @return /Bwea];^Q
* Returns the everyPage.
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*/ 7kwG_0QO
publicint getEveryPage(){ Ti/iD2g
return everyPage; =91'.c<
} vaxg^n|v9
G[^G~U\+!
/** V[bc-m
* @param everyPage \S@A
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* The everyPage to set. k?8W2fC
*/ IGqmH=-
publicvoid setEveryPage(int everyPage){ s,29_z7
this.everyPage = everyPage; Q.]
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} Q:MsD.
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/** Vl z T
* @return `x#~-
* Returns the hasNextPage. GSFT(XX
*/ y;>I'e
publicboolean getHasNextPage(){ !fV6KkV
return hasNextPage; ^/BE=$E\
} [:=[QlvV
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/** z0UO<Y?9
* @param hasNextPage vp|=q;Q%r
* The hasNextPage to set. c]n03o
*/ (hV"z; rI
publicvoid setHasNextPage(boolean hasNextPage){ %i
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this.hasNextPage = hasNextPage; *Fc&DQT(
} ;'
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/** :58'U|
* @return 1G;Ns] u
* Returns the hasPrePage. lG+ltCc$9
*/ Ww@;9US 3
publicboolean getHasPrePage(){ /t^lI%&
return hasPrePage; }:8>>lQ
} Q(IS=
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/** _Kj.
* @param hasPrePage c>!J@[,
* The hasPrePage to set. &aQ)x
*/ =arsoCa
publicvoid setHasPrePage(boolean hasPrePage){ MB 5[Js|
this.hasPrePage = hasPrePage; DQICD.X6R
} KEN-G
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/** .%<&W1
* @return Returns the totalPage. 4~Pto
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* "3MUrIsB>
*/ 4<K`yU]"
publicint getTotalPage(){
*4:/<wI!
return totalPage; xwxj j
} z{jAt6@7
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/** sN}@b8o@
* @param totalPage t>sX.=\$
* The totalPage to set. Lp WEu^j
*/ L#
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publicvoid setTotalPage(int totalPage){ ko>_@]Jb
this.totalPage = totalPage; =k7\g /
} N8q Z{CWn
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} Ve1] ECk
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hNo>)$v!s
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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 'uzv\[
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个PageUtil,负责对Page对象进行构造: tuUXW5!/
java代码: ;T+U&U0d|
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/*Created on 2005-4-14*/ wT=hO+
package org.flyware.util.page; D*gVS
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import org.apache.commons.logging.Log; Z^6(&Rh
import org.apache.commons.logging.LogFactory; P$>kBW53
walRqlo@
/** UeMe4$m
* @author Joa Kn$1W=B1.
* ] *VF Ws
*/ 3a}`xCO5
publicclass PageUtil { mZVOf~9E
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privatestaticfinal Log logger = LogFactory.getLog U(=9&c@]
O9X:1>a@i
(PageUtil.class); D>e\OfTR:
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/** 5l/l]
* Use the origin page to create a new page <^_Vl8%
* @param page o'C.,ic?C
* @param totalRecords #
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* @return =DTOI
*/ e=UVsYNx
publicstatic Page createPage(Page page, int cloSJmUlQ
e@-Mlq)
totalRecords){ {/xs9.8:JX
return createPage(page.getEveryPage(), TK/'=8
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page.getCurrentPage(), totalRecords); `A _8nW)
} ,Z7Z!.TY!
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/** =G F
* the basic page utils not including exception 7XWBI\SW
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handler }lTZq|;A
* @param everyPage +Z<Q^5w@
* @param currentPage j~*Z7iu
* @param totalRecords e=z_+gVm
* @return page x0h3jw+6
*/ ![]I%'s
publicstatic Page createPage(int everyPage, int qZsddll
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currentPage, int totalRecords){ 0s9z @>2
everyPage = getEveryPage(everyPage); y*b.eO
currentPage = getCurrentPage(currentPage); dX@A%6#?
int beginIndex = getBeginIndex(everyPage, {Y:ZY+
,Zf!KQw
currentPage); L##8+OJ.L
int totalPage = getTotalPage(everyPage, TWR$D
t<k[W'#
totalRecords); }`N2ZxC0AQ
boolean hasNextPage = hasNextPage(currentPage, "SU-^z
e_c;D2'F
totalPage); 5J+V:Xu{
boolean hasPrePage = hasPrePage(currentPage); }j(2Dl
.`&/QiD
returnnew Page(hasPrePage, hasNextPage, 1uS-Tx
everyPage, totalPage, )Ct*G=
N
currentPage, GP[r^Z
,;iBeqr5
beginIndex); RYZE*lWUh
} qm}>J^hnB#
<VaMUm<2
privatestaticint getEveryPage(int everyPage){ %|(?!w7
return everyPage == 0 ? 10 : everyPage; ZutB_uW
} yD"0=\
7IT l3>
privatestaticint getCurrentPage(int currentPage){ 4iv]N 4
return currentPage == 0 ? 1 : currentPage; #xP!!.DF(
} DqzA U7
.?0>5-SfY
privatestaticint getBeginIndex(int everyPage, int q|u8CX
\_*MJ)h)X
currentPage){ -[pCP_`)u
return(currentPage - 1) * everyPage; HD:%Yv
} |N$?_<H
<P^hYj-swh
privatestaticint getTotalPage(int everyPage, int mheU#&|
1n`1o-&l-
totalRecords){ \5[D7}
int totalPage = 0; D=~B7b:
1U7,X6=~
if(totalRecords % everyPage == 0) 9vp%6[
totalPage = totalRecords / everyPage; D!RE-w92X
else ]`@]<6
totalPage = totalRecords / everyPage + 1 ; *F
szGn<
O5^J!(.O\Z
return totalPage; "@{4.v^}!
} /:y2Up-
NYjS
privatestaticboolean hasPrePage(int currentPage){ MKe^_uF
return currentPage == 1 ? false : true; [{@zb-h
} [X }@Ct6
*vRI)>wU
privatestaticboolean hasNextPage(int currentPage, i$bzdc#s
XD^dlL
int totalPage){ _;e!ZZLG
return currentPage == totalPage || totalPage == fQQsb 5=i
"X5_-l
0 ? false : true; 6)wy^a|pb
} *^D@l%av;
|}M0,AS
If-,c^i
} f]ue#O
7!r#(>I6?1
;v1NL@w*
{Vxc6,=
&"[)s[m+t
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。 v]:+`dV
+mc[S
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 {Z#e{~m#
xJ~
gT
做法如下: `S \zqF<
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .kc"E
I7fb}j`/
的信息,和一个结果集List: *#1y6^
java代码: fVDDYo2\
%AG1oWWc>.
#v4LoNm
/*Created on 2005-6-13*/ sTtX$&Qu
package com.adt.bo; j0iAU1~_VX
|DE%SVZB
import java.util.List; !/j,hO4Z4
w;
4jx(
import org.flyware.util.page.Page; i iX\it$s
%kh#{*q$
/** Q(510)
* @author Joa iuC7Y|
*/ FxCZRo&
publicclass Result { PS=e\(6QC
#wenX$UTh3
private Page page; UvxSMD:A
OXHvT/L`
private List content; C$<"w,
VEj$^bpp5s
/** S]&8St
* The default constructor #bT8QbJ(
*/ -AjH}A[!
public Result(){ >Mvka;T]
super(); yiVG ]s
} ~:>AR` 9G
-<qxO
/** q,B3ru.?d
* The constructor using fields e>l,(ql
* %K[daXw6E8
* @param page :O $@shV
* @param content J
I<3\=:+
*/ FR:d^mL
public Result(Page page, List content){ "h=6Q+Ze
this.page = page; d^F|lc ]8
this.content = content; J["H[T*
} ^GMJ~[]
gmh5
%2M
/** KRYcCn
* @return Returns the content. fb\DiKsW
*/ ugYw<
publicList getContent(){ "8 N"Udu
return content; TQP+>nS,
} XZS5B~E
'
8|O=/m ^]
/** N&T:Lt_N
* @return Returns the page. yN*:.al
*/ o=pt_!i/
public Page getPage(){ d%0+i/p
return page; <i{K7}':
} .xO
_E1Ku;
!;%y$$gxh
/** /XcDYMKgh
* @param content dY} pN"
* The content to set. |6E
.M1
*/ %*lp< D
public void setContent(List content){ Q1Ux!$_
this.content = content; )kYOHS
} pb#mg^8
b"``D ?
/** KP3n^
$~
* @param page x97L6!
* The page to set. Lf. 1>s
*/ CSL#s^4T
publicvoid setPage(Page page){ gv#4#]
this.page = page; -hWC_X:9jP
} jM~Bu.7 i6
} TyF{tuF
2i\Q@h
17}$=#SX
V/PAi.GZ
Py|;kF~! [
2. 编写业务逻辑接口,并实现它(UserManager, j{"z4Y4
+$47v$p
UserManagerImpl) {`%hgR
java代码: 5IW8=$k~.)
fXO_g
.NJ|p=fy
/*Created on 2005-7-15*/ 9Bz0MUbrLl
package com.adt.service; <l$P&jSF3
Vtb1[cnna
import net.sf.hibernate.HibernateException; n`(~OO
-4w%Iy
import org.flyware.util.page.Page; rK1-Mu
Z!6UW:&~7
import com.adt.bo.Result; ?
-3\
)RN<GW'
/** ;QBh;jg4
* @author Joa j!\dn!Xwt
*/ ?}}qu'N:N
publicinterface UserManager { $5AC1g'
c%z'xM
public Result listUser(Page page)throws 8d!GZgC8R
Qzqc .T
HibernateException; a+`D'?z
PWH^=K
} =E(#YCx
Z) Wnow
`0bP0^w
mN*?%t
ExVDkt0
java代码: TVaA>]Fv
+dk fcG
Q&CElx?L
/*Created on 2005-7-15*/ .oqIZ\iik
package com.adt.service.impl; ? }yfKU`
`&!k!FZY*
import java.util.List; 4zjs!AK%
jVO{$j
import net.sf.hibernate.HibernateException; Y9Z]i$qS&k
Z^yNLF *&V
import org.flyware.util.page.Page; "
.4,."
import org.flyware.util.page.PageUtil; m^V5*JIh
_V2xA88
import com.adt.bo.Result; |A\a4f'G
import com.adt.dao.UserDAO; "?3`
import com.adt.exception.ObjectNotFoundException; !E2W\chi
import com.adt.service.UserManager; ` qUX.
o.m:3!RW
/** B(_WZa!
* @author Joa k()$:-V
*/ /vxm"CJR
publicclass UserManagerImpl implements UserManager { os4{0Mxu
u5B:^.:p
private UserDAO userDAO; dtZE67KS
4;<ut$G
/** Dnw| %6Y
* @param userDAO The userDAO to set. Fh8lmOL;?
*/ )1
m">s4
publicvoid setUserDAO(UserDAO userDAO){ (W[V?!1
this.userDAO = userDAO; DF_X
} lk3=4|?zsE
!4(zp;WY^
/* (non-Javadoc) o]ePP,
* @see com.adt.service.UserManager#listUser ]fBUT6
:YP #
(org.flyware.util.page.Page) d\]Yk]r
*/ ;Hmp f0$
public Result listUser(Page page)throws L\%orLEmK
0.TaXbi
HibernateException, ObjectNotFoundException { @WMA }\Cc
int totalRecords = userDAO.getUserCount(); k*?I>%^6#T
if(totalRecords == 0) "%qzj93>
throw new ObjectNotFoundException mh.+."<)F
Ts.wh>`
("userNotExist");
8|6
4R:
page = PageUtil.createPage(page, totalRecords); =LkR!R=
List users = userDAO.getUserByPage(page); 'Gl&Pa1g?
returnnew Result(page, users); C0jj(ku&
} }}|)Yq
^uBxgWIC
} ? *>]")[>
*.#oxcll
>UDd @
*=AqM14 @
Fv74bC%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 h[o6-f<D
as*4UT3
询,接下来编写UserDAO的代码: -=`#fDvBn
3. UserDAO 和 UserDAOImpl: 0@I S
java代码: F@ Swe
,<-G<${
6$\jAd|
/*Created on 2005-7-15*/ _8,()t'"
package com.adt.dao; |`TgX@,#9
En{`@JsM
import java.util.List; 1rKy@9
M_g?<rK
import org.flyware.util.page.Page; /D!;u]
M{g%cR0
import net.sf.hibernate.HibernateException; +N`ua
9h&R]yz;
/** aJ Z"D8C
* @author Joa Gg Jf7ie4
*/ +M'
H0-[
publicinterface UserDAO extends BaseDAO { _{<seA
/!h;c$
publicList getUserByName(String name)throws VTy9_~q
Xpe)PXb
HibernateException; %D$]VSP;
0:w"M<80
publicint getUserCount()throws HibernateException; eET&pP3Rp
AIMSX]m
publicList getUserByPage(Page page)throws R^?/' dr
2c6g>?
HibernateException; #Cpd9|
Wbr+KX8)
} yY?b.ty
Gx`L ks
}>)[<;M>%
Bn@(zHG+5&
C|pdv
java代码: Xs: 3'ua
ry9T U
>B]'fUt5a
/*Created on 2005-7-15*/ x
}Ad_#q
package com.adt.dao.impl; q$I:`&
hn#1%p6t
import java.util.List; q`-;AG|xF
%_ !bRo
import org.flyware.util.page.Page; =UUU$hq2
,]bB9tid
import net.sf.hibernate.HibernateException; [!!Q,S"
import net.sf.hibernate.Query; _ODbY;M
,eTU/Q>{,&
import com.adt.dao.UserDAO; T5a*z}L5
/c
uLc^(X
/** lpz2 m\
* @author Joa wgCa58H76
*/ Z#rB}
public class UserDAOImpl extends BaseDAOHibernateImpl CHe>OreiS
89r DyRJ;
implements UserDAO { d3=KTTi\
sI{ M
/* (non-Javadoc) !pD*p)`s
* @see com.adt.dao.UserDAO#getUserByName BD(Z5+EU1
E?_Z`*h
(java.lang.String) PLK3v4kVM!
*/ dqN5]Sb2B
publicList getUserByName(String name)throws ]]zPq<b2
` @nl
HibernateException { Q ]}Hd-
String querySentence = "FROM user in class Lhqz\ o
)wT-8o
com.adt.po.User WHERE user.name=:name"; c%MW\qx
Query query = getSession().createQuery l1f\=G?tmU
O)[1x4U
(querySentence); vM5k_D
query.setParameter("name", name); 8ji_#og
return query.list(); y3fGWa*7e
} U&?v:&c#&n
Ytl4kaYS
/* (non-Javadoc) EOCN&_Z;
* @see com.adt.dao.UserDAO#getUserCount() 6oGYnu;UZ
*/ Uu `9"
publicint getUserCount()throws HibernateException { )ubiB^g'm
int count = 0; gP;&e:/3
String querySentence = "SELECT count(*) FROM Q)IKOt;N]
xL\0B,]
user in class com.adt.po.User"; thI
F&
Query query = getSession().createQuery Evedc*z~P
$m/)FnU/
(querySentence); ZjF 4v
count = ((Integer)query.iterate().next oz,e/v8~
s,]z[qB#$
()).intValue(); zx)z/1
return count; +mn,F};
} Le\?+h42>
HhvdqvIEG
/* (non-Javadoc) x^y'P<ypw
* @see com.adt.dao.UserDAO#getUserByPage y !_C/!d
-4
SY=NC_
(org.flyware.util.page.Page) @0/+_2MH-
*/ v_DedVhe
publicList getUserByPage(Page page)throws YB2VcF.LU
JsODzw
HibernateException { MB]<Dyj,
String querySentence = "FROM user in class ~XOTs
xCc[#0R{
com.adt.po.User"; fTK3,s1=
Query query = getSession().createQuery ?`PvL!'
lE4HM$p
(querySentence); _sTROd)Vh
query.setFirstResult(page.getBeginIndex()) )8$=C#qC[
.setMaxResults(page.getEveryPage()); ^G}47(
return query.list(); rR(X9i
} % ~H=sjg
u)+8S/ )
} E?
;0)'h
T7hcnF$
{#@W)4)cA
"i[@P)
ZzJ?L4J5v
至此,一个完整的分页程序完成。前台的只需要调用 |l]XpWV
[J?aD`{#O
userManager.listUser(page)即可得到一个Page对象和结果集对象 -C(crn
a6) BqlJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]QlwR'&j/n
huh6 t !
webwork,甚至可以直接在配置文件中指定。 b?tB(if!I
j~[z2tV
下面给出一个webwork调用示例: |}Nn!Sj>#;
java代码: #."-#"0
0tT(W^ho g
:&V h?
/*Created on 2005-6-17*/ ?kbiMs1;u
package com.adt.action.user; #_^Lb]jkM
e#$]Y?,
import java.util.List; j i7[nY
Lr~=^{
import org.apache.commons.logging.Log; ix)M`F%P3
import org.apache.commons.logging.LogFactory; $QN"wL||
import org.flyware.util.page.Page; wsI`fO^A8
UCB/=k^m
import com.adt.bo.Result; Qp_isU
import com.adt.service.UserService; Bg x'9p/
import com.opensymphony.xwork.Action; 3z{?_;bR
1W^taJH]
/** Krqtf
* @author Joa M_/7D|xl/T
*/ QI'Oz{vE
publicclass ListUser implementsAction{ Vt:~q{9*k
iTgt}]L
privatestaticfinal Log logger = LogFactory.getLog OR~8sU
P3+5?.p.
(ListUser.class); 4%>$-($
s(/;U2"e
private UserService userService; }v}P
.P
R;&AijS8
private Page page; 7&jTtKLj
jFL #s&ft
privateList users; P}n_IV*@
,Z&xNBX
/* -#u=\8
* (non-Javadoc) %)zodf
* r!_-"~`7E
* @see com.opensymphony.xwork.Action#execute() Ug>~Rq]
*/ `ZYoA
t]C~
publicString execute()throwsException{ V5V
bJBpf
Result result = userService.listUser(page); [+T.at
page = result.getPage(); 4xjP iHd<
users = result.getContent(); h-q3U%R4}@
return SUCCESS; [9evz}X
} %[Wh [zZy
\XCe22x]
/** J\twZ>w~0
* @return Returns the page. 6-N?mSQU
*/ N} G[7Rp8l
public Page getPage(){ vdivq^%=a
return page; {6|38$Rl
} Y!-M_v /
\A 2r]
/** _|kxY'_[8
* @return Returns the users. J=9FRC
*/ P{kur} T
publicList getUsers(){ /M1ob: m
return users; ;DqWh0
} N.,X<G.H
`i3NG1
v0
/** q9KHmhUD
* @param page fInb[
* The page to set. HVR /7&g
*/ ry`Ho8N
publicvoid setPage(Page page){ x-WmMfcz&
this.page = page; ak$f"py
x
} X`kk]8=
lA|
5E?
/** 'N (:@]4N
* @param users (-UYB9s
* The users to set. 6iVxc|Ia
*/ Ra)3+M!x
publicvoid setUsers(List users){ ]#)()6)2v
this.users = users; ?PuBa`zDE
} '}ptj@,
\=VtHu92=
/** ;w{tv($$
* @param userService T"{>t
* The userService to set. S'Q@ScJ
*/ @Q)OGjaq
publicvoid setUserService(UserService userService){ kyR:[+je
this.userService = userService; uw>Ba %5
} g1/:Q%R,
} pnl{&<$C%C
jwc)Lj}
E:UW#S%A
f
fiK6@,
orzZ{87
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, >,V9H$n
x|/|jzJSX
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 I5k$H$
k3lS8d7
么只需要: B]nEkO'a:
java代码: CKYc\<zR0l
: %lTU
}MJy
+Z8&
<?xml version="1.0"?> w$3,A$8
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork py$Q
z`.<U{5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pNG:0
7Od
-I*bt
1.0.dtd"> ($q-_m
"Gsc;X'id
<xwork> *>Ns_su7W
TH%Qhv\]
<package name="user" extends="webwork- ;v}GJ<3
j$M h+5
interceptors"> q }i]'7
F|SXn\
<!-- The default interceptor stack name dPW#C5dm
m ifxiV
--> \r/rBa\
<default-interceptor-ref ? ^0:3$La
du<tGsy
name="myDefaultWebStack"/> [g7L&`f9
g;H=6JeG/
<action name="listUser" Lu?C-$a C
.p<:II:6
class="com.adt.action.user.ListUser"> Km qMFB62
<param hE-h`'ha`
@x*c1%wg
name="page.everyPage">10</param> L7n D|
<result EuZ<quwWg
@:oXN]+
_
name="success">/user/user_list.jsp</result> Ot4 Z{mA
</action> b)6D_Az7c
%R}qg6dL
</package> T:27r8"Rh
OV1_|##LC
</xwork> 0z`a1 %U
\ ZgE
/Wi[OT14
I:=S0&%)
:tz#v`3o
QE^$=\l0
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 3lf=b~Zi)
-WY<zJ
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。 7o7)0l9!
0eT(J7[ <
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ()Y~Q(5ji
UE8kpa)cQ
vk}n,ecl
OSRp0G20k\
_~'=C#XI)
我写的一个用于分页的类,用了泛型了,hoho hCi 60%g/n
_zR+i]9
java代码: +Zb;Vn4
(of#(I[m7
"Bh}}!13
package com.intokr.util; T-'OwCB1q
)MtF23k)g
import java.util.List; P@,XEQRd`
4-l8,@9
/** .N,bIQnj
* 用于分页的类<br> 57'*w]4f
* 可以用于传递查询的结果也可以用于传送查询的参数<br> BGvre'67
* G4Q[Th
* @version 0.01 &agWaf1%a
* @author cheng `
)/vq-9
*/ pd:WEI
,
public class Paginator<E> {
ncZ+gzK|"
privateint count = 0; // 总记录数 3OrczJ=[UF
privateint p = 1; // 页编号 F8nYV
privateint num = 20; // 每页的记录数 >"??!|XG^
privateList<E> results = null; // 结果 e6`Jbu+J<f
jte.Xy~g
/** '*Z1tDFS
* 结果总数 h\$$JeSV]
*/ +! ]zA4x
publicint getCount(){ DEBB()6,
return count; 2bv=N4ly
} x!?u^
f&=AA@jLv
publicvoid setCount(int count){ nXaC3W:"
this.count = count; +vw\y
} \S"is z
.r|tSfm6
/** j%Y#(Q>
* 本结果所在的页码,从1开始 =Z{O<xw'
* )\1@V+!E%
* @return Returns the pageNo. '50OgF'
*/ ;o
6lf_
publicint getP(){ OyStq i
return p; ;(b9#b.
} M-$%Rzl_
lXx=But
/** ^6jV_QM#
* if(p<=0) p=1 sG(~^hJ_
* 9Uh"iMB
* @param p g1;:KzVv
*/ zv|2:4H
publicvoid setP(int p){ l^!
?@Kg,z
if(p <= 0) )1Y{Q Y}l
p = 1; X@ --m6-
this.p = p; ^3G{|JB!+
} kYM~d07 V
|O{m2Fi
/** 272q1~&
* 每页记录数量 im${3 >26
*/
YC*"Thuu
publicint getNum(){ lz/8
return num; '@a}H9>}
} aEBu *`-j
DMAIM|h
/** T"(&b~m2b4
* if(num<1) num=1 _no/F2>!/n
*/ hnffz95
publicvoid setNum(int num){ +xRK5+}9
if(num < 1) L\37xJo
num = 1; -m\u
this.num = num; Wt*cIZ
} mbKZJ{|4s
kq?Ms|h
/** nxO"ua
* 获得总页数 ^NLmgwQ
*/ aacpM[{f
publicint getPageNum(){ n|6Ic,:[
return(count - 1) / num + 1; aR[JD2G
} uY{|szC^2
PoHg,n]
/** mWv3!i;G<s
* 获得本页的开始编号,为 (p-1)*num+1 hM_lsc
*/ 0$(WlP|
publicint getStart(){ \/93Dz
return(p - 1) * num + 1; 0^v`T%|fTX
} e-~N"
_H9 MwJ
/** d|jNf</`
* @return Returns the results. w{{gu1#]G
*/ .nO\kg oK
publicList<E> getResults(){
&U{#Kt5q
return results; C/_ZUF(V
} @hl.lq
jxP;>K7O
public void setResults(List<E> results){ fPU`/6
this.results = results; k}S :RK
} goLL;AL
3_C|z,\:
public String toString(){ hMa]B*o/-
StringBuilder buff = new StringBuilder y>S.?H:P
W}nlRbN?
(); 50"pbzW
buff.append("{"); dSLU>E3g
buff.append("count:").append(count); ;Y)w@bNt@
buff.append(",p:").append(p); R%Hi+#/dr-
buff.append(",nump:").append(num); +[Dx?XM
buff.append(",results:").append u :}%xD6
Y`KqEjsC*
(results); QfmJn((
buff.append("}"); ZVW'>M7.
return buff.toString(); @MoKWfc
} B[qzUD*P_n
Ih@61>X.o*
} !d'GE`w T
M|VyV(f
GmK^}=frj