Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 e Wc_ N
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (FM4 ^#6
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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 Q2*/`L}m\
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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 O
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分页支持类: ;xL67e%?
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java代码: GA.BI"l
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package com.javaeye.common.util; aw1P5aPmX
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import java.util.List; \0D$Mie
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publicclass PaginationSupport { ?p(kh^ z
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publicfinalstaticint PAGESIZE = 30; ICk(z~D~
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privateint pageSize = PAGESIZE; -<6v:Z
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privateList items; KL
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privateint totalCount; USprsaj
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privateint[] indexes = newint[0]; j5zFDh1(
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privateint startIndex = 0; T$u~E1
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public PaginationSupport(List items, int [ dGO,ndE
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totalCount){ |B
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setPageSize(PAGESIZE); d^tVD`Fm
setTotalCount(totalCount); C(s\LI!r
setItems(items); w}d}hI
setStartIndex(0); PQ,+hq
} jA,|JgN|n
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public PaginationSupport(List items, int &RWM<6JP
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totalCount, int startIndex){ Fqo&3+J4
setPageSize(PAGESIZE); J2'K?|,m
setTotalCount(totalCount); 90p3V\LO
setItems(items); i (0hvV>'
setStartIndex(startIndex); Hr6wgYPi
} H "O$&
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public PaginationSupport(List items, int f4
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totalCount, int pageSize, int startIndex){ @m?{80;uQ
setPageSize(pageSize); >{QdMn
setTotalCount(totalCount); JPsSw
setItems(items); i *B:El1
setStartIndex(startIndex); WKxm9y
V
} `
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publicList getItems(){ QhCY}Q?X
return items; ~6kJ~R4
} M\dO({o
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publicvoid setItems(List items){ )
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this.items = items; QNb>rLj52
} |#V(p^
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publicint getPageSize(){ -?5$ PH
return pageSize; ".E5t@ }?m
} ywEDy|Wn$~
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publicvoid setPageSize(int pageSize){ _W |R;Cz]
this.pageSize = pageSize; -AC`q/bCD
} 9^!wUwB
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publicint getTotalCount(){ *0~M
return totalCount; n$YE !D'
} 2m\m/O
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publicvoid setTotalCount(int totalCount){ "<x&pQZ%
if(totalCount > 0){ ~0ooRUWU7
this.totalCount = totalCount; 5U~OP
int count = totalCount / Px#$uU
yb?{LL-uy
pageSize; uB;_vC
if(totalCount % pageSize > 0) /[iG5~G
count++; 69/?7r
indexes = newint[count]; (zC
for(int i = 0; i < count; i++){ t:=k)B
indexes = pageSize * H_Os4}
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i; $/paEn"
} _88QgThb
}else{ Y\p$SN
this.totalCount = 0; 8R}K?+]
} @!<d0_dnC
} V&[eSVY?
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publicint[] getIndexes(){ x'qWM/
return indexes; -`Q}tg>cT
} AK *N
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publicvoid setIndexes(int[] indexes){ 30_ckMG"g
this.indexes = indexes; ej52AK7
} 2tf6GX:
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publicint getStartIndex(){ N_G4_12(
return startIndex; e:OyjG5_
} 6/6Rah!
*b"CPg/\
publicvoid setStartIndex(int startIndex){ ;'HF'Z
if(totalCount <= 0) XsUUJuCG
this.startIndex = 0; /.P9MSz0G
elseif(startIndex >= totalCount) 2xn<E>]
this.startIndex = indexes Pz@/|&]
`(DJs-xD
[indexes.length - 1]; MCU9O
elseif(startIndex < 0) Q0~j$Jc
this.startIndex = 0; ^.vmF>$+I
else{ 6>,#
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this.startIndex = indexes C),7- ?
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[startIndex / pageSize]; TsHF
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} EgNH8i
} `c(\i$1JY)
8Z# 21X>
publicint getNextIndex(){ AIh*1>2Xn
int nextIndex = getStartIndex() + _faJ B@a_
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pageSize; <'&F;5F3V
if(nextIndex >= totalCount) =Ndli>x}1
return getStartIndex(); -;pOh;WG
else 9&K/GaG
return nextIndex; ]1sNmi$T
} [se^.[0,
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publicint getPreviousIndex(){ 5/MED}9C(
int previousIndex = getStartIndex() - t3b@P4c\
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pageSize; VVuR+=.&
if(previousIndex < 0) i8~r
return0; JE!("]&
else IgM
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return previousIndex; yC
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} -$YJfQE6G
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} Ld(NhB'7
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抽象业务类 *)> do
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java代码: o| D^`Z
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/** d?hz LX
* Created on 2005-7-12 4D"4zp7
*/ 6)[<)?A.[
package com.javaeye.common.business; #3MKH8k&~
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import java.io.Serializable; ,2`~ NPb
import java.util.List; H}nJbnU
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import org.hibernate.Criteria; C1QV[bJK
import org.hibernate.HibernateException; mhzYz;}
import org.hibernate.Session; fz}?*vPW
import org.hibernate.criterion.DetachedCriteria; o\6iq
import org.hibernate.criterion.Projections; E5UcZ7
import <1@
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org.springframework.orm.hibernate3.HibernateCallback; G!Zyl^
import v0@)t&O
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org.springframework.orm.hibernate3.support.HibernateDaoS @Zm Jz
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upport; s".HEP~]=
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import com.javaeye.common.util.PaginationSupport; JNo8>aFOb
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public abstract class AbstractManager extends T PYDs+U
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HibernateDaoSupport { yA;W/I4
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privateboolean cacheQueries = false; 8_Z/ o5s
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privateString queryCacheRegion; X9XI;c;b-
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publicvoid setCacheQueries(boolean g1|w? pI1
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cacheQueries){ ~V+l_:
this.cacheQueries = cacheQueries; 3?E}t*/
} 5 DFZ^~
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publicvoid setQueryCacheRegion(String C2/}d? bki
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queryCacheRegion){ \Tm}mAvK/o
this.queryCacheRegion = SY
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queryCacheRegion; K2ewucn
} &;>4N"]
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publicvoid save(finalObject entity){ qO()w
getHibernateTemplate().save(entity); {-WTV"L5*2
} lhPGE_\
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publicvoid persist(finalObject entity){ v?j!&d>
getHibernateTemplate().save(entity); @8gEH+r
} LwdV3 vb#
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publicvoid update(finalObject entity){ "JT;gaEm
getHibernateTemplate().update(entity); n?QZFeI`
} 12(wj6Q
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publicvoid delete(finalObject entity){ ]~jN^"o_B
getHibernateTemplate().delete(entity); )bDnbO$s_
} r@$ w*%
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publicObject load(finalClass entity, (:sZ
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finalSerializable id){ J@#?@0]F
return getHibernateTemplate().load c`kQvXx
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(entity, id); REA;x-u*
} 4v.d-^
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publicObject get(finalClass entity, fx?$9(r,
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finalSerializable id){ u"+}I,'L
return getHibernateTemplate().get m5-9yQ=.
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(entity, id); >. DC!QV
} |wp,f%WK
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publicList findAll(finalClass entity){ g9>~HF$U
return getHibernateTemplate().find("from x';uCKWV
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" + entity.getName()); r"]'`qP,
} W{Z^n(f4
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publicList findByNamedQuery(finalString yrr)
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namedQuery){ # cFr
return getHibernateTemplate TFH&(_b
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().findByNamedQuery(namedQuery); OW5t[~y]
} id,NONb\
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publicList findByNamedQuery(finalString query, wCb(>pL0
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finalObject parameter){ 4Z5#F]OA7
return getHibernateTemplate HEY4$Lf(I
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().findByNamedQuery(query, parameter); ;YH[G;aJ
} &Lj@9\Dh
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publicList findByNamedQuery(finalString query, ,=PKd&
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finalObject[] parameters){ j1U 5~%^
return getHibernateTemplate u, kU$
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().findByNamedQuery(query, parameters); tP(h9|[N
} bcz-$?]
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publicList find(finalString query){ Y83GKh,*
return getHibernateTemplate().find s&tE_
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(query); h @/;`E[
} 2qU&l|>
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publicList find(finalString query, finalObject 7P**:b
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parameter){ < bUe/m
return getHibernateTemplate().find ,+1m`9}
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(query, parameter); w{,4rk;Hr
}
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public PaginationSupport findPageByCriteria zG9|K
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(final DetachedCriteria detachedCriteria){ Sc$UZ/qPT
return findPageByCriteria ";NRzY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~~qWI>.4
} Pqp *
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public PaginationSupport findPageByCriteria =$^MQ\S0p
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(final DetachedCriteria detachedCriteria, finalint fZN><3MO>
uzU{z;
startIndex){ Z"v<0]rN
return findPageByCriteria C/@LZ OEL
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(detachedCriteria, PaginationSupport.PAGESIZE, *3+-W
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startIndex); `jsEN ;<
} ERz;H!pU8
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public PaginationSupport findPageByCriteria gS9>N/b|
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(final DetachedCriteria detachedCriteria, finalint !iu5OX7K|
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pageSize, P,z:Z|}8
finalint startIndex){ VLvS$0(}Z
return(PaginationSupport) \
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getHibernateTemplate().execute(new HibernateCallback(){ +RDJY(Y$
publicObject doInHibernate tw K^I6@
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(Session session)throws HibernateException { +wfVL|.Wq
Criteria criteria = /b[2lTC-e
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detachedCriteria.getExecutableCriteria(session); *b|NjwmB
int totalCount = Te-Amu
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((Integer) criteria.setProjection(Projections.rowCount 0!GAk
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()).uniqueResult()).intValue(); b>=_*nw9
criteria.setProjection ~^US/"
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(null); DSyXr~p8
List items = 5W? PCOh\
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criteria.setFirstResult(startIndex).setMaxResults i'HQQWd
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(pageSize).list(); L^J-("e_
PaginationSupport ps = 4,P bg|
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new PaginationSupport(items, totalCount, pageSize, HEF?mD3h
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startIndex); -K%5(Eg
return ps; \OwpD,'
} v/Pw9j!r;m
}, true); +s[\g>i
} 2&LQg=O
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public List findAllByCriteria(final $95~5]-nh
blt'={Z?.x
DetachedCriteria detachedCriteria){ 8*a),
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return(List) getHibernateTemplate pbk$o{$`W
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().execute(new HibernateCallback(){ xTV{^=\rS
publicObject doInHibernate ]7YNIS
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(Session session)throws HibernateException { KG9t3<-`
Criteria criteria = E1V^}dn
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detachedCriteria.getExecutableCriteria(session); HIc a nk
return criteria.list(); OM83S|1s
} _ -..~K.|
}, true); LF<wt2?*
} -_A$DM!^=w
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public int getCountByCriteria(final kBWrqZ6
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DetachedCriteria detachedCriteria){ GHc/Zc"iX
Integer count = (Integer) =\kMXB
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getHibernateTemplate().execute(new HibernateCallback(){ wxQ>ifi9Z
publicObject doInHibernate /BA{O&Ro^
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(Session session)throws HibernateException { +OaUP*\Dd
Criteria criteria = /pH(WHT+/H
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detachedCriteria.getExecutableCriteria(session); Qs 2.ef?
return <,@%*G1-
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criteria.setProjection(Projections.rowCount *|:Q%xr-
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()).uniqueResult(); eny/
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} Ve 3 ;
}, true); n(ir[w#,]"
return count.intValue(); EMvHFu
} ,XKCz ]8V
} sH#X0fG
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用户在web层构造查询条件detachedCriteria,和可选的 qv2!grp]*W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2?7(A
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PaginationSupport的实例ps。 B|=|.qp$)
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ps.getItems()得到已分页好的结果集 7
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ps.getIndexes()得到分页索引的数组 -6~' cm
ps.getTotalCount()得到总结果数 (nSml,gU
ps.getStartIndex()当前分页索引 0JyVNuHn
ps.getNextIndex()下一页索引 HM[klH]s=
ps.getPreviousIndex()上一页索引 ]1`g^Z@ 0
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =6 r:A<F!n
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 J1ON,&[J
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一下代码重构了。 A&5:ATQ/|
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我把原本我的做法也提供出来供大家讨论吧: D/(CU#i"
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首先,为了实现分页查询,我封装了一个Page类: _c(4o:
java代码: f{#j6wZM
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/*Created on 2005-4-14*/ _wDS#t;!M
package org.flyware.util.page; \Q$HXK
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/** Of}|ib^t
* @author Joa yx{3J
* T)~9Wac
*/ -~f511<
publicclass Page { ]B\H~Kn
N!&:rK
/** imply if the page has previous page */ BHFY%6J!
privateboolean hasPrePage; }CGSEr4'w~
Cr ?4Ngw
/** imply if the page has next page */ "hz\Z0zg2
privateboolean hasNextPage; \Gp*x\<^Z
JC?N_kP%W
/** the number of every page */ {D&9UZm
privateint everyPage; UL@9W6
s,]%dG!
/** the total page number */ v;1F[?@3Y
privateint totalPage; n'FwM\
J%C#V}z7E
/** the number of current page */ KDP H6
privateint currentPage; C(T;>if0NH
C#pZw[
/** the begin index of the records by the current /'.=sH
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query */ N5zlT
privateint beginIndex; Y]|:?G7l]
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/** The default constructor */ {No L
public Page(){ uGN^!NG-0
d@C&+#QDF
} )v4b
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/** construct the page by everyPage eJCjJ)
* @param everyPage 6vKS".4C
* */ o]n!(f<(*
public Page(int everyPage){ g| <wyt[
this.everyPage = everyPage; YGvUwj'2a
} R<ND=[}s
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/** The whole constructor */ n.oUVr=nX
public Page(boolean hasPrePage, boolean hasNextPage, @F*wg
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int everyPage, int totalPage, 'J)2g"T@
int currentPage, int beginIndex){ =:,xxqy
this.hasPrePage = hasPrePage; e-hjC6Q U
this.hasNextPage = hasNextPage; a&{X!:X
this.everyPage = everyPage; i+3fhV
this.totalPage = totalPage; vl Ez9/H
this.currentPage = currentPage; ~ (On|h
this.beginIndex = beginIndex; LjFqZrH
} t`'iU$:1f
4\ c,)U}
/** owpWz6k7
* @return 3-n19[zk
* Returns the beginIndex. NSAF4e
*/ y&[y=0!
publicint getBeginIndex(){ |! SOG
return beginIndex; I&|f'pn^<
} |C%Pjl^YkV
Scm36sT{
/** qm*}U3K
* @param beginIndex .9[45][FK
* The beginIndex to set. [k$*4u>
*/ CI:^\-z
publicvoid setBeginIndex(int beginIndex){ o KD/rI
this.beginIndex = beginIndex; j9+I0>#X
} h&3YGCl
qGmNz}4D5
/** X .F^$
* @return %#L]]-%
* Returns the currentPage. 2?C`4AR[2H
*/ 3VnQnd E
publicint getCurrentPage(){ |%a4`w
return currentPage; X@)z80
} \<0B 1m
y4:H3Sk
/** w9RS)l2FQ
* @param currentPage 5qUTMT['T
* The currentPage to set. |wE3UWsy
*/ |H}m 4-+*
publicvoid setCurrentPage(int currentPage){ ixm&aW6<
this.currentPage = currentPage; 5v)(8|.M
} }ov&.,vQ
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/** Z BUArIC
* @return {yU+)t(.
* Returns the everyPage.
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*/ $2DuB
publicint getEveryPage(){ R
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return everyPage; )\;Z4x;]U
} i|)Su4Dw
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/** JPM))4YDR
* @param everyPage L(>=BK*
* The everyPage to set. g @I6$Z
*/ dUznxZB
publicvoid setEveryPage(int everyPage){ H y"x
this.everyPage = everyPage; ,fIe&zq
} M~*u;vA/
~n')&u{
/** IL/Yc1
* @return -F"QEL#
* Returns the hasNextPage. D'l5Zd
*/ I
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publicboolean getHasNextPage(){ )Rat0$6
return hasNextPage; 8n BL\{'B[
} Ioy
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/** Cd79 tu|
* @param hasNextPage U'UQ|%5f
* The hasNextPage to set. [OTJV pC
*/ b*fgv9Kh'
publicvoid setHasNextPage(boolean hasNextPage){ [+*$\
this.hasNextPage = hasNextPage; R`";Z$~{
} )Dp/('Z2
LLWB
/** AB Xl
* @return _{vkX<s
* Returns the hasPrePage. `dMqe\o%!
*/ F["wDO
publicboolean getHasPrePage(){ iGDLZE+?
return hasPrePage; c H-@V<
} 5m=I*.qE
MC((M,3L
/** K'iIJA*Sn
* @param hasPrePage #eU.p&Zc
* The hasPrePage to set. uV-'~8
*/ a9zw)A
publicvoid setHasPrePage(boolean hasPrePage){ o[ENp'r
this.hasPrePage = hasPrePage; O<)y-nx;X
} ki0V8]HP
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/** _mS!XF~`P
* @return Returns the totalPage. `s '#
* t&5%?QyM
*/ 5F t5@UF~
publicint getTotalPage(){ VN0mDh?E
return totalPage; iVFkYx%}
} SYeadsvF
04%S+y.6&Y
/** &|%6|u9
* @param totalPage ]`g<w#
* The totalPage to set. rPc7(,o*
*/ YJs|c\ eq?
publicvoid setTotalPage(int totalPage){ IC{eE
this.totalPage = totalPage; y~
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} Zn,>]X
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} +9O5KI?P
}pkj:NT
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 lT\a2.E
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个PageUtil,负责对Page对象进行构造: ODc9r }
java代码: ;o/>JHGj
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/*Created on 2005-4-14*/ _8}QlT
package org.flyware.util.page; zJ+8FWy:S
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; C 8#@+ Q.
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/** <?D[9Mk$
* @author Joa IfO;S*Qt
* *F>v]8
*/ !@u>A_
publicclass PageUtil { 30PZ{c&Rll
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privatestaticfinal Log logger = LogFactory.getLog H7+Xs%
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(PageUtil.class); {Z; jhR,
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/** Sz{O2lY
* Use the origin page to create a new page 41#w|L
\
* @param page %or,{mmiM:
* @param totalRecords ,1q_pep~?%
* @return <";,GaZQ
*/ t3Z_Dp~\
publicstatic Page createPage(Page page, int uUE9g
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totalRecords){ S1n3(U:m
return createPage(page.getEveryPage(), j4FeSGa
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page.getCurrentPage(), totalRecords); ` b !5^W
} *O:r7_ Y0
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/** h@7FY
* the basic page utils not including exception kE.x+2
I O%6 O
handler dAP|:&y@
* @param everyPage }MR1^
* @param currentPage : FAH\
* @param totalRecords a m-b!l!q^
* @return page 53 QfTP
*/ U,/6;}
publicstatic Page createPage(int everyPage, int U(&oj e
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currentPage, int totalRecords){ \&V0vN1
everyPage = getEveryPage(everyPage); y AF+bCXo
currentPage = getCurrentPage(currentPage); ~5ZvOX6L2
int beginIndex = getBeginIndex(everyPage,
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"Th$#3
currentPage); d-bqL:/
int totalPage = getTotalPage(everyPage, ZaFb*XRgS
s"=6{EVqk3
totalRecords); ?3z- _8#
boolean hasNextPage = hasNextPage(currentPage, ;TQf5|R\K
qZ@0]"h
totalPage); *fO3]+)d+
boolean hasPrePage = hasPrePage(currentPage); aYL|@R5;e
[MX;,%;;
returnnew Page(hasPrePage, hasNextPage, ^/wfXm
everyPage, totalPage, s)voII&
currentPage, aI
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c_{z(W"
beginIndex); =9L$L|W
} {-9jm%N
^\ ?O4,L
privatestaticint getEveryPage(int everyPage){ 1{pmKPu
return everyPage == 0 ? 10 : everyPage; M_B:{%4
} z2ms^Y=j
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privatestaticint getCurrentPage(int currentPage){ \u`)kJ5o1
return currentPage == 0 ? 1 : currentPage; :Ud[f`t
} L~{_!Q
LiDvaF:@L!
privatestaticint getBeginIndex(int everyPage, int dGZntT2D
W[[oSqp
currentPage){ gOT+%Ab{_
return(currentPage - 1) * everyPage; )/4(e?%=
} |sqZ $Mu
R~L0{`
0
privatestaticint getTotalPage(int everyPage, int tc_f;S`k
wYeB)1.
totalRecords){ lM\LN^f5*
int totalPage = 0; zHB_{(o7
f<i7@%
if(totalRecords % everyPage == 0) Rg29
totalPage = totalRecords / everyPage; F9c`({6k
else RnVtZ#SCh
totalPage = totalRecords / everyPage + 1 ; O|kKwadC
JL}\*
return totalPage; !yjo
} %kf>&b,Mi
0m[dP
privatestaticboolean hasPrePage(int currentPage){ \a"Ct'
return currentPage == 1 ? false : true; u]C`6)>
} O(2cWQ
BOlAm*tFt
privatestaticboolean hasNextPage(int currentPage, i< (s}wg
QrD o|GtE
int totalPage){ {hSGv
return currentPage == totalPage || totalPage == nR
\'[~+
${~|+zdB
0 ? false : true; >(9F
} ,7]k fB
4}v@C|.p
u'Q?T7
} *E>.)B i
;sdN-mb
lYf+V8{
$<@\-vYvr@
]7sx;KFv
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。 p?(L'q"WK
{B$2"q/~
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 :@
uIxa$[
n_[i0x7#
做法如下: O/AE}]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Df07y<>7Q
1N`vCt]w
的信息,和一个结果集List: @`u?bnx]e
java代码: KHiFJ_3
\jW)Xy
`T*U]/zQ
/*Created on 2005-6-13*/ hi{%pi&!T
package com.adt.bo;
V+MK'<#B
t
*6loS0+
import java.util.List; &!.HuRiuC
ux2013C_
import org.flyware.util.page.Page; 8``;0}'PC
6y+b5-{'
/** wjU.W5IR
* @author Joa
~m=EM;
*/ I\P Bu$Ww
publicclass Result { 2F_
R/{D
?v]-^X=&
private Page page; 4 (?MUc
E,G<_40
private List content; ;#?M)o:q
ucYkxi`x
/** IxSV? k
* The default constructor Q ~|R Z7G
*/ V%L/8Q~
public Result(){ g1m-+a
super(); @_'OyRd8
} sPYX~G&T
Ayx^Wp*s
/** *3{J#Q6fk3
* The constructor using fields Qez SJ
io
* @98;VWY\
* @param page H>7dND2;
* @param content kN9yO5h7
*/ oVkq2
public Result(Page page, List content){ uK*|2U6t
this.page = page; Dk)}|GJ()"
this.content = content; =WZ%H_oxi
} 6k0^ x Q
a_T,t'6
/** vS;'}N
* @return Returns the content. VC&c)X
*/ ^tAO_~4
publicList getContent(){ tiQ;#p7%
return content; Fxd{ Zk`
} q|#MB7e/
mMw;0/n
/** ma8wmQ9 JR
* @return Returns the page. S)\8|ym6!
*/ 9/TY\?U
public Page getPage(){ Eek9|i"p
return page; QX0Y>&$)
} ;_JH:}j
[$\>~nj=
/** :iCM=k
* @param content XF,<i1ZlM
* The content to set. )q^ Bj$
*/ P;91~``b-
public void setContent(List content){ \P?ToTTV
this.content = content; is#8R:7.:
} D5A=,\uk
D!FaE N
/** # mT]j""
* @param page jz:gr=*z
* The page to set. PnWD}'0V
*/ 3;/?q
publicvoid setPage(Page page){ hw,^G5m
this.page = page; +$pJ5+v
} Q7Ij4
} =I4.Gf"~f
\KM|f9-b
F-0UdV
H^(L90
v[#)GB
_5
2. 编写业务逻辑接口,并实现它(UserManager, cdp0!W4Gi
D1"7s,Hmu
UserManagerImpl) /8e W@IO.F
java代码: C ?7X"~~
I6dm@{/:>
d79N-O-
/*Created on 2005-7-15*/ s44iEh=V(I
package com.adt.service; ,b'4CF
aWvd`qA9r
import net.sf.hibernate.HibernateException; moO_-@i
kL7^$
import org.flyware.util.page.Page; ?SX_gYe9
1r4,XSk
import com.adt.bo.Result; 981!2*
EF;,Gjh5p
/** 31XU7A
* @author Joa olty4kGD$V
*/ ROoE%%8I
publicinterface UserManager { 0n5UKtB
@>O&Cpt
public Result listUser(Page page)throws _Y-$}KwY!
rx:lKoOnB
HibernateException; -9G]x{>
,P@QxnQ
} <-)9>c:k
T-P@u-DU
T
T"3^@
0xBY(#;Q
R<g =\XO'y
java代码: JuJ5qIal
N$Hqa^!'T
&&C~@WY,r
/*Created on 2005-7-15*/ wItz cY1m
package com.adt.service.impl; i QqbzOY
D44I"TgqD
import java.util.List; G%OpO.Wf
k+\7B}7F
import net.sf.hibernate.HibernateException; q3\!$IM.
I7Zq}Pxa
import org.flyware.util.page.Page; kPJ~X0Fr{t
import org.flyware.util.page.PageUtil; ` u=<c
h.b+r~u
import com.adt.bo.Result; hEcYpng~
import com.adt.dao.UserDAO; )6G+ tU'
import com.adt.exception.ObjectNotFoundException; |Ow$n
import com.adt.service.UserManager; 7SHo%bA
VRhRwdC
/** ,4Y sZ
* @author Joa 1UyH0`&
*/ Fe4esg-B<
publicclass UserManagerImpl implements UserManager { >@Khm"/T
M,{<TpCx
private UserDAO userDAO; X,53c$
}rxFS
<j
/** [NR1d-Wg
* @param userDAO The userDAO to set. riEqW}{
*/ :eLLDp<
publicvoid setUserDAO(UserDAO userDAO){ ^z?=?%{
this.userDAO = userDAO; JOHp?3 "4
} *<3iEeO/R
EQ~I'#m7
/* (non-Javadoc) *EE|?vn
* @see com.adt.service.UserManager#listUser Y;PDZbK3
4+,*sn
(org.flyware.util.page.Page) 9;:7e*x]lc
*/ F~P/*FFK
public Result listUser(Page page)throws OAyE/Q|
,,2_/u\"/i
HibernateException, ObjectNotFoundException { rN'k4V"K
int totalRecords = userDAO.getUserCount(); Cj=J;^vf
if(totalRecords == 0) ceI
[hM
throw new ObjectNotFoundException CCwK8`%
EkV!hqs*
("userNotExist"); ,|>nF;.Y
page = PageUtil.createPage(page, totalRecords); L/%xbm~
List users = userDAO.getUserByPage(page); <m9JXO:5
returnnew Result(page, users); 'jwTGT5x
} a\|X^%2g
w7[0
} .y(@Y6hO
!-@SS>
f(W,m
>.;
lHRK'?Q
9Z}S]-u/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;+!xZOmm
DwQp$l'NfW
询,接下来编写UserDAO的代码: (jt*u (C&Y
3. UserDAO 和 UserDAOImpl: Ez wF`3RjK
java代码: 96k(XLR
+2f>
M4q
+._f.BRmX.
/*Created on 2005-7-15*/ FxMMxY,*%
package com.adt.dao; il<gjlyR]L
(u$!\fE-et
import java.util.List; __Vg/C!W
an #jZ[
import org.flyware.util.page.Page; Ni/|C19Z
F12S(5Z0%
import net.sf.hibernate.HibernateException; h/w]
:a#|
/** B/[hi%~
* @author Joa NO%|c|B|
*/ *(>F'>F1"
publicinterface UserDAO extends BaseDAO { YeR7*[l
V/+H_=|
publicList getUserByName(String name)throws |8b$x| B
\r)_-
HibernateException; bUpmU/RW
!:R^}pMhIk
publicint getUserCount()throws HibernateException; Ss*LgK_
'lSnyW{
publicList getUserByPage(Page page)throws zSX'
^*j[&:d
HibernateException; _%C_uBLi
50O7=
} mCZF5r
E0WrpGZ
m7bn%j-{$f
)4 VLm
}Etd#">
java代码: Z)b)v
t\E-6u
}-k_?2"A
/*Created on 2005-7-15*/ 4 @ydK
package com.adt.dao.impl; Vb"T],N1m
H-PW(
import java.util.List; <%5-Pz p
o>QFdx
import org.flyware.util.page.Page; !nqm ;96
.T
N`p*
import net.sf.hibernate.HibernateException; `i_L?C7
import net.sf.hibernate.Query; '/n%}=a=
3 z{5c
import com.adt.dao.UserDAO; >V ]*mS%K
6>P
/** D+@/x{wX2
* @author Joa ;^*+:e
*/ hIg, 0B
public class UserDAOImpl extends BaseDAOHibernateImpl bo?3E +B
C$Hl`>?$
implements UserDAO { A(!ZZ9Wc
WP#_qqO
/* (non-Javadoc) m}'t'l4 c
* @see com.adt.dao.UserDAO#getUserByName ~*Sbn~U
v1tN
DyM6
(java.lang.String) _|5FrN
*/ OKLggim{
publicList getUserByName(String name)throws ofJ]`]~VG
KTAe~y
HibernateException { M&BM,~
String querySentence = "FROM user in class `__?7"p
)\
#B.w7y5*
com.adt.po.User WHERE user.name=:name"; V3hm*{ON
Query query = getSession().createQuery O%Gsk'mo
IP4b[|ef
(querySentence); ^Hhw(@`qf
query.setParameter("name", name); g cK"
return query.list(); tX`[6`
} F>oxnhp6
q MT.7n:
/* (non-Javadoc) 6/WK((Fd
* @see com.adt.dao.UserDAO#getUserCount() 0)] C&;}_M
*/ aSj1P/A
publicint getUserCount()throws HibernateException { A>1p]#
int count = 0; G]NtX4'4
String querySentence = "SELECT count(*) FROM +` Y ?-
zt>_)&b
user in class com.adt.po.User"; SAxa7B/U2
Query query = getSession().createQuery gBiQIhz
L)nVpqm
(querySentence); $?J LCa
count = ((Integer)query.iterate().next '?>O
Sph"w08
()).intValue(); s2v#evI`+
return count; qLi1yH
} n#L2cv~Aj"
wj:3
/* (non-Javadoc) %LZM5Z^
* @see com.adt.dao.UserDAO#getUserByPage VOK$;s'9}
"M#`y!__
(org.flyware.util.page.Page) _x|8U'|Ce
*/ EKS<s82hF&
publicList getUserByPage(Page page)throws WUK.>eM0
^?.:}
HibernateException { 7LZb*+>
String querySentence = "FROM user in class BNoCE!
|ij5c@~&
com.adt.po.User"; 1eyyu!
Query query = getSession().createQuery }/}`onRZ
y!c7y]9__2
(querySentence); 3R[J,go
query.setFirstResult(page.getBeginIndex()) vKOn7
.setMaxResults(page.getEveryPage()); j#>![km Mu
return query.list(); &OR*r7*Z
} )n[Mh!mn
?,e:c XhE2
} T:~W.3
2u H\8A+'f
5@rqU(]<
M~Dc5\T
AS"|r
至此,一个完整的分页程序完成。前台的只需要调用 $"n)C
{Qmb!`F
userManager.listUser(page)即可得到一个Page对象和结果集对象 [a*>@IR
qa`(,iN
的综合体,而传入的参数page对象则可以由前台传入,如果用 > 5:e1a?9
aNU%OeQA
webwork,甚至可以直接在配置文件中指定。 _7HJ'
+~.Jw#HqS
下面给出一个webwork调用示例: gm$MEeC
java代码: R:m=HS_
:>ST)Y@]w
{#Cm> @')
/*Created on 2005-6-17*/ P>Rqy
package com.adt.action.user; B&j+fi
@<JQn^M
import java.util.List; !7*/lG
CnA)>4E*'
import org.apache.commons.logging.Log; gy`qEY~B&
import org.apache.commons.logging.LogFactory; G"sc;nT
import org.flyware.util.page.Page; F>R)~;Ja
'E8Qi'g
import com.adt.bo.Result; r_RTtS#
import com.adt.service.UserService; t^;Fq{>
import com.opensymphony.xwork.Action; [M>_(u6
O~]G(TMs8W
/** n}kz&,
* @author Joa =B%e0M
*/ (2)9TpE;
publicclass ListUser implementsAction{ 8?pZZtad
3iL&;D
privatestaticfinal Log logger = LogFactory.getLog rWmi 'niu
M)Q+_c2*
(ListUser.class); 3_/d=ZI\
r5wXuA,Um
private UserService userService; 7^X_tQf
Rx2|VD
private Page page; XL9lB#v^
SJ@_eir\o
privateList users; /omVMu
V@f#/"u'
/* &p/k VM
* (non-Javadoc) o 4wKu
* .C?g nOq
* @see com.opensymphony.xwork.Action#execute() &T}e93]
*/ e0 EJ[bG
publicString execute()throwsException{ CB)#;
|aDB
Result result = userService.listUser(page); mj~CCokF{?
page = result.getPage(); >?<d}9X
users = result.getContent(); TUr}p aw_
return SUCCESS; MLX.MUS
} Lq^/Z4L
cKAl 0_[f"
/** 1XRVbQt
* @return Returns the page. d0az#Yg!
*/ |{Q,,<C
public Page getPage(){ ktRdf6:~
return page; R)z|("%ec
} e#^by(1@}
Fjb[Ev
/** ~gD]JiiA
* @return Returns the users. ,zaveQ~l
*/ 6D<A@DR9J
publicList getUsers(){ lhU# /}Z
return users; &D#v0!e~x
} `x{gF8GV
:1Cc~+]w(u
/** OMU#Sx!6
* @param page Hn)=:lI
* The page to set. RZjR d
*/ sMK/l @7
publicvoid setPage(Page page){ EC0auB7G
this.page = page; T}* '9TB
} hV)I
C9
MRc^lYj{
/** 19 _F\32
* @param users 5YasD6l
* The users to set. =k
z;CS+
*/ [#tW$^UD
publicvoid setUsers(List users){ /e\dsC{uJ
this.users = users; y:L|]p}huE
} "yumc5kt
!p$V7pFu6
/** Yu=^`I
* @param userService {ig@Iy~DT
* The userService to set. |j<'[gB\p
*/ Hw
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publicvoid setUserService(UserService userService){ Gmb57z&:
this.userService = userService; t
+_G%tv
} 6~s,j({^
} iu .{L(m
NKRXY~zHh
7~&Y"&
~Y(M>u.+!
@?U5t1O<
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, @tA.^k0`
S^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 v3p..A~XZ.
j.K yPWO
么只需要: ,\M'jV"SK
java代码: ?g&]*zc^\
{SJLM0=Z
|w5#a_adM
<?xml version="1.0"?> <}=D ?bXw
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork E$T#o{pai
_rM%N+$&d_
1.0//EN" "http://www.opensymphony.com/xwork/xwork- fITml6mbE
Vswi /(
1.0.dtd"> _:z~P<%s
7]Egu D4
<xwork> ! 9e>J
{2nXItso
<package name="user" extends="webwork- z} %to0W
8Xr3q eh+
interceptors"> BC+HP9<]
;u%h wlo
<!-- The default interceptor stack name 3Rm$
hug12Cu
--> ,ZSuo4
<default-interceptor-ref r{btBv
V6L_aee}CK
name="myDefaultWebStack"/> M$)+Uo2
~^eAS;
<action name="listUser" o.Q9kk?L
PQK_*hJG"
class="com.adt.action.user.ListUser"> dx~Wm1
<param Kk,->q<1
kBTuM"
name="page.everyPage">10</param> b7n~z1$
<result `XnFc*L 1
}8svd#S+
name="success">/user/user_list.jsp</result> 17 GyE=Uu
</action> Xk3Ufz]QN
1Nz\3]-
</package> ..!yf e"5
LV[4z o]=
</xwork> \bg^E>-
%tMfOW
Hq~ 2,#Ue
L*_xu _F
FR <wp
sOJ~PRA
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 [ /D/
Kq*^*vWC
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。 aH6pys!O
Mf
*qr9*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 c]9OP9F
1v Thb
&qr7yyY
oH;Y} h
#\jPBLc
我写的一个用于分页的类,用了泛型了,hoho H0Tt(:.&
T&c[m!}X|t
java代码: dU\fC{1Z
=:b/z1-v
#: F)A_Y
package com.intokr.util; 3lJK[V{'#'
aV ^2
import java.util.List; 6QV/8IX
B<)(7GTv7"
/** 8dpVB#]pp,
* 用于分页的类<br> -&&mkK
B!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> P)H%dJ^l
* TQ BL!w
* @version 0.01 Pa.!:N-
* @author cheng ^'h~#7s
*/ >3ODqRu
public class Paginator<E> { >hXUq9;:
privateint count = 0; // 总记录数 N&n{R8=^"
privateint p = 1; // 页编号 ILQg@Jl
privateint num = 20; // 每页的记录数 n"pADTaB
privateList<E> results = null; // 结果 +,%x&L&I
[W;14BD7
/** %!q(zql
* 结果总数 Yc
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*/ v|hi;l@7E
publicint getCount(){ K+7xjFoDIR
return count; [;2v[&Po
} u66w('2
Cr&ua|%F
publicvoid setCount(int count){ h m"B kOA
this.count = count; N5s_o0K4TU
} G6
GXC`^+
_E~uuFMn*R
/** OS!47Z /q
* 本结果所在的页码,从1开始 ]/a?:24 [
* ^cY5!W.q8
* @return Returns the pageNo. DJ\lvT#j
*/ ~(^[TuJC
publicint getP(){ Ro1l:P)C`
return p; [)a,rrhj
} GY!&H"%
_x lgsa
/** `wq\K8v
* if(p<=0) p=1 7W>T=
@
* Op|Be
* @param p BG|Kw)z*KM
*/ \/5 8#
publicvoid setP(int p){ 3"B|w^6'2
if(p <= 0) w90y-^p%
p = 1; "?Y0Ng[
this.p = p; S`-z$ph}
} g` Wr3
{c$W-t):U|
/** Z?b.
PC/
* 每页记录数量 ~E)I+$,
*/ a{HvrWs?Q
publicint getNum(){ u_uC78`p
return num; )I*V('R6|
} 86I".R$d
>
4^U=T#
/** xv)7-jlx
* if(num<1) num=1 !is8`8F8
*/ ZpwB"%e$
publicvoid setNum(int num){ G1D(-X4ALZ
if(num < 1) Um|:AT}`^
num = 1; { u;ntDr
this.num = num; 3(CUC
} X4o8
l[ L{m7
/** i#C?&
* 获得总页数 6=zme6D
*/ IX3r$}4
publicint getPageNum(){ gU8'7H2
return(count - 1) / num + 1; &r_:n t
} 5ogbse"
;eWVc;H
/** aB$Y5
* 获得本页的开始编号,为 (p-1)*num+1 2.|Y
*/ *z(.D\{%
publicint getStart(){ 3Y=S^*ztd
return(p - 1) * num + 1; Obw uyhjQ
} =]D##R
I*0W\Qz@
/** %Jw;c`JM
* @return Returns the results. ;DRJL
*/ <=0_[M
publicList<E> getResults(){ ?1[go+56X
return results; Wy|=F~N
} rm2TWM|
KLoHjBq
public void setResults(List<E> results){ BtjsN22
this.results = results; *:_.cbo
} ]-0
&[@I4@
[H"Ods~_`
public String toString(){ 79i>@u%
StringBuilder buff = new StringBuilder l5aQDkp}
=7$YBCuF
(); F[J;u/Z
buff.append("{"); 7%o\O{,U
buff.append("count:").append(count); -
@
buff.append(",p:").append(p); :@pmgp
buff.append(",nump:").append(num); s(zG.7*3n
buff.append(",results:").append Yc9 M6=E^
te:@F]A
(results); y<5s)OehG
buff.append("}"); uD+;5S]us
return buff.toString(); V57^0^Zp`
} MRiETd"
ysSEgC3
} Q:%gJ6pa
Zaq:l[%
@ws3X\`<C