Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 pBLO
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 L,L7WObA
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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 v:;cTX=x`#
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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 G$<0_0GF
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分页支持类: nsk
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java代码: m"]ys#
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package com.javaeye.common.util; 1fZ:^|\
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import java.util.List; IrC=9%pd$R
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publicclass PaginationSupport { k6S<46}h|
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publicfinalstaticint PAGESIZE = 30; Z]d]RL&r
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privateint pageSize = PAGESIZE; q#Vf2U55m
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privateList items; :_ox8xS4
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privateint totalCount; ,pzCJ@5
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privateint[] indexes = newint[0]; t`B']Ac;T
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privateint startIndex = 0; (=9&"UH
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public PaginationSupport(List items, int XT"c7]X
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totalCount){ T:$_1I $
setPageSize(PAGESIZE); bk]|C!7$
setTotalCount(totalCount); ,vPF=wq
setItems(items); H;1}Nvvd
setStartIndex(0); ;\N*iN#K
} $EF@x}h:A
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public PaginationSupport(List items, int oDa{HP\O]W
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totalCount, int startIndex){ 2Fi*)\{
setPageSize(PAGESIZE); ~l~g0J
setTotalCount(totalCount); ): 6d_g{2
setItems(items); .>n|#XK
setStartIndex(startIndex); 605|*(
} stPCw$@
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public PaginationSupport(List items, int oV`sCr5%
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totalCount, int pageSize, int startIndex){ \ 714 Pyy
setPageSize(pageSize); m@YLZ
setTotalCount(totalCount); r;z A `
setItems(items); "RLb wm~
setStartIndex(startIndex); -wB AFr
} o*_ D
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publicList getItems(){ nKdLhCN'=
return items; hh9{md\
} #eYVZ=E
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publicvoid setItems(List items){ /eQn$ZRP,
this.items = items; %L3]l
} Pp2)P7
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publicint getPageSize(){ eAMT7 2_
return pageSize; zKNk(/y
} *rLs!/[Z_
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publicvoid setPageSize(int pageSize){ lS^0*(Y
this.pageSize = pageSize; @zbXG_J
} }8HLyK,4
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publicint getTotalCount(){ JFZ p^{
return totalCount; bb{+
} 8{C3ijR
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publicvoid setTotalCount(int totalCount){ #82B`y<<y/
if(totalCount > 0){ *M:Bhw
this.totalCount = totalCount; DN+`Q{KS
int count = totalCount / ry'(mM
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pageSize; (Gcl,IW
if(totalCount % pageSize > 0) J}JnJV8|G
count++; v,;?+Ck
indexes = newint[count]; =R05H2hs
for(int i = 0; i < count; i++){ jKzjTn9{E
indexes = pageSize * s>5 Z
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i; )n.peZ
} P]n
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}else{ S~T[*Z/m
this.totalCount = 0; X6)LpMm
} yFSL7`p+
} ^|Y!NHYH$Z
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publicint[] getIndexes(){ iQKfx#kt
return indexes; om1 /9
} XL:7$
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publicvoid setIndexes(int[] indexes){ rhrlEf@
this.indexes = indexes; ]Uu/1TTf
} |fUSq1//
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publicint getStartIndex(){ hXCDlCO
return startIndex; D)Zv
} DCj!m<Y&
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publicvoid setStartIndex(int startIndex){ Y3[@(
if(totalCount <= 0) + '`RJ,K+[
this.startIndex = 0; 5GKz@as8
elseif(startIndex >= totalCount) 9g7T~|P
this.startIndex = indexes 9cLKb
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[indexes.length - 1]; _#+i;$cO-X
elseif(startIndex < 0) 'Gk|&^
this.startIndex = 0; W;=ZQ5Lw
else{ \21!NPXH2
this.startIndex = indexes bu]bfnYi9
jzQgDed ]
[startIndex / pageSize]; wNlp4Z'[
} fRiHs\+
} 8L:0Wp
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publicint getNextIndex(){ ?^dyQhb
int nextIndex = getStartIndex() + 9:1ZL_yf
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pageSize; ;.iy{&$
if(nextIndex >= totalCount) 5q\]] LV>
return getStartIndex(); TtzB[F
else ?1YK-T@
return nextIndex; Q8_d]V=X:
} Q-\: u~
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publicint getPreviousIndex(){ j0J6ySlY
int previousIndex = getStartIndex() - 8=d9*lm
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pageSize; fIu/*PFPVY
if(previousIndex < 0) u7S7lR"lxW
return0; o\N),;LM
else 2n\EZ
return previousIndex; n'SnqJ&}
} $3So`8Bm[$
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} u!O)\m-
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抽象业务类 }q^CR(h (R
java代码: MD +Q_
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/** ;aSEv"iWX
* Created on 2005-7-12 K#>B'>A\
*/ gD-<^Q-
package com.javaeye.common.business; xu3qX"
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import java.io.Serializable; #<{sP0v*
import java.util.List; =7a9~&|
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import org.hibernate.Criteria; Lx.X#n.]T
import org.hibernate.HibernateException; @>:r'Fmu-
import org.hibernate.Session; O%OeYO69
import org.hibernate.criterion.DetachedCriteria; "bJW yUb
import org.hibernate.criterion.Projections; ./u3z|q1
import 0y?bwxkc
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org.springframework.orm.hibernate3.HibernateCallback; D ,nF0p
import LVX.s tN#p
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org.springframework.orm.hibernate3.support.HibernateDaoS d;K,2
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upport; T{Av[>M
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import com.javaeye.common.util.PaginationSupport; BPW2WSm@<
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public abstract class AbstractManager extends lwSA!W
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HibernateDaoSupport { d-X<+&VZ
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privateboolean cacheQueries = false; $%ps:ui~X
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privateString queryCacheRegion; n* uT
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publicvoid setCacheQueries(boolean Dc
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cacheQueries){ QN":Qk(,q
this.cacheQueries = cacheQueries; r+>gIX+Fl
} 0`:0m/fsU
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publicvoid setQueryCacheRegion(String arm26YA-,
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queryCacheRegion){ Pa+%H]vB
this.queryCacheRegion = l4RZ!K*X_"
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queryCacheRegion; Nzf tc
} Lc=t,=OhGe
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publicvoid save(finalObject entity){ /;
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getHibernateTemplate().save(entity); 13kl\<6
} b-,4< H8m
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); tw,uV)xm
} ';Y0qitGB
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publicvoid update(finalObject entity){ )vn{?Ulj
getHibernateTemplate().update(entity); ;ry~x:7L7
} Pd)mLs Jg
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publicvoid delete(finalObject entity){ ]V^ >aUlj
getHibernateTemplate().delete(entity); HQX.oW
}
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publicObject load(finalClass entity, ,N93 H3(
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finalSerializable id){ wNtC5
return getHibernateTemplate().load :<hM@>eFn
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(entity, id); k..AP<hH
} }20~5!
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publicObject get(finalClass entity, f?W_/daP
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finalSerializable id){ WUrE1%u
return getHibernateTemplate().get t^
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(entity, id); \xG_q>1_
} LGB}:;$AL
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publicList findAll(finalClass entity){ -!q^/ux
return getHibernateTemplate().find("from - ({h @
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" + entity.getName()); *O_>3Hgl
} >jz9o9?8
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publicList findByNamedQuery(finalString w$iQ,--
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namedQuery){ xIA] 5@;a
return getHibernateTemplate OYSq)!:
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().findByNamedQuery(namedQuery); 5\V""fH
} KT[ZOtu
K
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publicList findByNamedQuery(finalString query, DQ<4`wE M
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finalObject parameter){ zX lcu_rc
return getHibernateTemplate Fs"i fn0
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().findByNamedQuery(query, parameter); 9fm9xTL
} >v2/0>U
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publicList findByNamedQuery(finalString query, _ _!LTpp
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finalObject[] parameters){ P?p]sLrP
return getHibernateTemplate |M`'
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().findByNamedQuery(query, parameters); )pSA|Qt N
} t W+"/<U
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publicList find(finalString query){ 7r&lW<:>
return getHibernateTemplate().find |sd G<+
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(query); 0<7sM#sI!
} auga`*
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publicList find(finalString query, finalObject !wN2BCSY@
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parameter){ Ge_fU'F
return getHibernateTemplate().find +5S>"KAUt0
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(query, parameter); yDfH`]i)U
} ?7}ybw3t]
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public PaginationSupport findPageByCriteria D&i\dgbK
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(final DetachedCriteria detachedCriteria){ %N)B8A9kh
return findPageByCriteria ]DKRug5
Q 9fK)j1$
(detachedCriteria, PaginationSupport.PAGESIZE, 0); EB|
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} ((C|&$@M
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public PaginationSupport findPageByCriteria ?z`={oN
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(final DetachedCriteria detachedCriteria, finalint !m^;wkrY
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startIndex){ b"WF]x|^
return findPageByCriteria b"uO BB
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(detachedCriteria, PaginationSupport.PAGESIZE, f`:GjA,J$
- w*fS,O
startIndex); PChe w3
} ;89kL]
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public PaginationSupport findPageByCriteria bn)1G$0|
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(final DetachedCriteria detachedCriteria, finalint w]t'2p-'
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pageSize, T:u>7?8o
finalint startIndex){ hH 5}%/vF
return(PaginationSupport) L/Q[N^ (^
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getHibernateTemplate().execute(new HibernateCallback(){ (IBT|K
publicObject doInHibernate Wk\(jaL%
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(Session session)throws HibernateException { g]lEG>y1R
Criteria criteria = ep=r7Mft
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detachedCriteria.getExecutableCriteria(session); KEtV
int totalCount = nm@h5ON_
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((Integer) criteria.setProjection(Projections.rowCount >*RU:X
Ec!!9dgRQ
()).uniqueResult()).intValue(); [
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criteria.setProjection
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(null); '|DW#l\n
List items = I)rO|
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criteria.setFirstResult(startIndex).setMaxResults (da`aRVDp
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(pageSize).list(); . :Skc
PaginationSupport ps = cc|W1,q
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new PaginationSupport(items, totalCount, pageSize, eAf i!!Z<
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startIndex); ,B[j{sE
return ps; Z^_qXerjP
} BM<q;;pO
}, true); s0/O/G?
} #RBrii-,
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public List findAllByCriteria(final I/`"lAFe
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DetachedCriteria detachedCriteria){ R9U{r.AA
return(List) getHibernateTemplate a_RY Yj
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().execute(new HibernateCallback(){ ^.6[vmmq
publicObject doInHibernate Co1d44Q
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(Session session)throws HibernateException { krUtOVI
Criteria criteria = +/ZIs|B4,z
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detachedCriteria.getExecutableCriteria(session); yp#!$+a}
return criteria.list(); ZwkUd-=0i
} JT?u[pQ^
}, true); J8qFdNK
} DZSS
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public int getCountByCriteria(final wXIRn?z
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DetachedCriteria detachedCriteria){ KqK]R6>
Integer count = (Integer) $aV62uNf
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getHibernateTemplate().execute(new HibernateCallback(){ o-\h;aQJ
publicObject doInHibernate fz(YP=@ZnP
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(Session session)throws HibernateException { |V a:*3u
Criteria criteria = F7DA~G!
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detachedCriteria.getExecutableCriteria(session); I0m7;M7 P
return Gyq 6?
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criteria.setProjection(Projections.rowCount W'C>Fn}lO?
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()).uniqueResult(); ZSuoD$~k[
} TxJk.c
}, true); OG5{oH#K
return count.intValue(); t#^Cem<
} 1SExlU
}
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用户在web层构造查询条件detachedCriteria,和可选的 Rw?w7?I
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 3Bl|~K;-
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PaginationSupport的实例ps。 "V[j&B)P
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ps.getItems()得到已分页好的结果集 L]=]/>jQ6
ps.getIndexes()得到分页索引的数组 YK/? mj1x
ps.getTotalCount()得到总结果数 Qc7*p]E&
ps.getStartIndex()当前分页索引 [+\He/M6
ps.getNextIndex()下一页索引 2j-l<!s
ps.getPreviousIndex()上一页索引 A%^?z.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 TAYh#T=S
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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 z qA>eDx
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一下代码重构了。 TCp9C1Q4
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我把原本我的做法也提供出来供大家讨论吧: A|"T8KSMB
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首先,为了实现分页查询,我封装了一个Page类: 7m#EqF$P
java代码: E-WpsNJ)X
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/*Created on 2005-4-14*/ W>TG?hH
package org.flyware.util.page; e)}E&D;${
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/** #._JB-,'
* @author Joa n/v.U,f&l@
* cxR.:LD}
*/ .rBU"Rbo
publicclass Page { 0Z2XVq~T$
ep8UWxB5
/** imply if the page has previous page */ |sGJum&=
privateboolean hasPrePage; 7&id(&y/
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/** imply if the page has next page */ {iyJHY
privateboolean hasNextPage; QvbH " 7
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/** the number of every page */ /4+L2O[
privateint everyPage; .s\lfBo9
2*sTU
/** the total page number */ &<><4MQ
privateint totalPage; a<-aE4wdm
_n:RA)4*
/** the number of current page */ uihH")Mo
privateint currentPage; OG{*:1EP
=Htt'""DN
/** the begin index of the records by the current |M?s[}ll
,=e.QAF!"
query */ -3ePCAtXbe
privateint beginIndex; S:z|"u:+
>$ZhhM/} J
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/** The default constructor */ +s<6eHpm
public Page(){ {>km]CG
reR@@O
} @v`.^L{P
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/** construct the page by everyPage f%PLR9Nh5@
* @param everyPage 2|"D\N
* */ /[?}LrDO
public Page(int everyPage){ P<>NV4
this.everyPage = everyPage; Gd|kAC
g
} e;v"d!H/
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/** The whole constructor */ Ab[o~X"
public Page(boolean hasPrePage, boolean hasNextPage, b"\lF1Nf&o
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int everyPage, int totalPage, vVMoCG"f
int currentPage, int beginIndex){ F=Xb_Gd`
this.hasPrePage = hasPrePage; 3rK\
f4'
this.hasNextPage = hasNextPage; r\QV%09R
this.everyPage = everyPage; aEzf*a|fSV
this.totalPage = totalPage; or#]
![7N
this.currentPage = currentPage; JFI*Pt;X9
this.beginIndex = beginIndex; sPc}hG+N
} vw>(JCR
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/** mxEe
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* @return .<vXj QE
* Returns the beginIndex. _#H d2h
*/ >NPK;Vu
publicint getBeginIndex(){ .,6o):
return beginIndex; +\["HS7+'0
} `}`Q qv
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/** bLS10^g5
* @param beginIndex q0q-Coh>
* The beginIndex to set. oAifM1*0
*/ onmpMU7w
publicvoid setBeginIndex(int beginIndex){ =?W7OV^BE
this.beginIndex = beginIndex; xyo~p,(~t
} Y'000#+
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/** y=sae
* @return Lios1|5
* Returns the currentPage. e<uf)K=(C
*/ ^>%.l'1/(
publicint getCurrentPage(){ @-K[@e/uwy
return currentPage; r]-n,
} Ae=JG8Ht~
hlreeXv
/** )n"0:"Ou
* @param currentPage 2u-J+
* The currentPage to set. .h4NG4FIF
*/ ,){#J"W
publicvoid setCurrentPage(int currentPage){ X*MK(aV3
this.currentPage = currentPage; Z^Um\f
} Z79 6;qk
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/** >VZxDJ$R
* @return v.*fJ
* Returns the everyPage. $@kOMT
*/ <BT18u\
publicint getEveryPage(){ Kn3Xn`P?
return everyPage; R`$Y]@i&B
} CAx$A[f<
W%5))R$
/** s)E8}-v
* @param everyPage tq,^!RSbZ
* The everyPage to set. #/Ob_~-?j
*/ =\u,4
publicvoid setEveryPage(int everyPage){ |Isn<|_
this.everyPage = everyPage; >`3F`@1L0
} !YpH\wUyvP
8&HBR #
/** ;F-
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* @return IR]5,K^l
* Returns the hasNextPage. dh%O {t
*/ >Q<XyAH~
publicboolean getHasNextPage(){ BPkL3Ev1V
return hasNextPage; -rYb{<;ST
} L<oQKe7Q:
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D
/** _'Jjt9@S
* @param hasNextPage (Z @dz
* The hasNextPage to set. )H]L/n
*/ i._RMl5zg
publicvoid setHasNextPage(boolean hasNextPage){ Fs~*-R$
this.hasNextPage = hasNextPage; x>mI$K(6M
} wQhu U
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/** /~s<@<1!X
* @return '\d
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* Returns the hasPrePage.
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*/ 0\"#Xa+}8
publicboolean getHasPrePage(){ <uBRLe`)
return hasPrePage; huA?*fat
} x6JV@wA&
2gklGDJD
/** z&n2JpLY7
* @param hasPrePage jP/Vqe%%8
* The hasPrePage to set. ;=IJHk1&
*/ <sm"3qs"_
publicvoid setHasPrePage(boolean hasPrePage){ vO$cF*
this.hasPrePage = hasPrePage; m;4ti9
} ceJ#>Rj
"9^b1UH<
/** \tvL<U"'
* @return Returns the totalPage. bh5P98s
* Wtw,YFT
*/ (
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publicint getTotalPage(){ f?^-JZ
return totalPage; dZIbajs'
} r?Mf3U^G
PfU\.[l$
/** #>KiX84
* @param totalPage NwOV2E6@OW
* The totalPage to set. 6q'Q?Uw^
*/ ,6MJW#~]
publicvoid setTotalPage(int totalPage){ Hmm0H6&u
this.totalPage = totalPage; `peR ,E
} 0+qC_ISns
o:cTc:l)
} @,= pG
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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 N2 3:+u<)E
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个PageUtil,负责对Page对象进行构造: fnr8{sr.2Z
java代码: OESKLjFt
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/*Created on 2005-4-14*/ [G|(E
package org.flyware.util.page; +J{ErsG?6P
1E||ft-1i*
import org.apache.commons.logging.Log; XRkUv>Yk
import org.apache.commons.logging.LogFactory; q,#s m'S
G Wa6FX:/
/** "1a!]45 +
* @author Joa Hc<@T_h+2
* Q3=5q w^
*/ y2?9pVLa\y
publicclass PageUtil { 1k:yU(
6~ y'
privatestaticfinal Log logger = LogFactory.getLog KC; o
[ /*;}NUv
(PageUtil.class); ;Qq_
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/** ]D5Maid+
* Use the origin page to create a new page q$yg^:]2
* @param page w+j\Py_G"
* @param totalRecords =AzkE]
* @return VfJ{);
*/ A9SL|9Q
publicstatic Page createPage(Page page, int n2-+.9cY
ami>Pp
totalRecords){ OW=3t#"7Kp
return createPage(page.getEveryPage(), g8'8"9:xC
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page.getCurrentPage(), totalRecords); DFZ@q=ZT
} b@4UR<
):tv V
/** z]%@r 7
* the basic page utils not including exception =ZU!i0
K
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handler `Nvhp]E
* @param everyPage BcpbS%S
* @param currentPage GwDOxH'
* @param totalRecords NWiDNK[VE}
* @return page 5QXU"kWH
*/ zb[kRo&a0W
publicstatic Page createPage(int everyPage, int g%]<sRl:-
PCgr`($U
currentPage, int totalRecords){ h"8[1
;
everyPage = getEveryPage(everyPage); {W{;VJKQ2
currentPage = getCurrentPage(currentPage); ,%x2SyA
int beginIndex = getBeginIndex(everyPage, fX,O9d$
WW3Jxd
currentPage); A_ &IK;-go
int totalPage = getTotalPage(everyPage, %YF
/=l
{_.(,Z{
totalRecords); mMZrBz7r
boolean hasNextPage = hasNextPage(currentPage, X#0yOSR
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totalPage); 9cN@y<_I
boolean hasPrePage = hasPrePage(currentPage); $4ZV(j]
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returnnew Page(hasPrePage, hasNextPage, FVP,$
everyPage, totalPage, +&f_k@+
currentPage, O,^s)>c
Yyd}>+|<,
beginIndex); !~F oy F
} S{2;PaK
8'3&z-
privatestaticint getEveryPage(int everyPage){ u&o4?]6
return everyPage == 0 ? 10 : everyPage; G.XxlI}
} a(O@E%|u
<bCB-lG*Kb
privatestaticint getCurrentPage(int currentPage){ 6K8v:yYPa
return currentPage == 0 ? 1 : currentPage; 6?US<<MQ
} Fq+Cr?-
xA:;wV
privatestaticint getBeginIndex(int everyPage, int |p+FIr+
qR2cRepV
currentPage){ (dNF)(wn
return(currentPage - 1) * everyPage; 1z2v[S&pk
} IN1n^f$:
#2Q%sE?
privatestaticint getTotalPage(int everyPage, int %j1 7QD8
|SMigSu r`
totalRecords){ #>_fYjT
int totalPage = 0; }2BNy9q@
d@*dbECG
if(totalRecords % everyPage == 0) +N,Fq/x
totalPage = totalRecords / everyPage; RDQ]_wsyKG
else zn= pm#L
totalPage = totalRecords / everyPage + 1 ; mqJD+ K
tQ'R(H`
return totalPage; 8aRmHy"9l
} lc
fAb@}2
(?XIhpd
privatestaticboolean hasPrePage(int currentPage){ !7#*Wdt+P
return currentPage == 1 ? false : true; ]CS
N7Q+l
} u}R|q
MxGQM>
privatestaticboolean hasNextPage(int currentPage, /#_[{lSr?
l1 08.ao
int totalPage){ G&wYV[Ln
return currentPage == totalPage || totalPage ==
E)I&? <g
{nA+-=T
0 ? false : true; j/T@-7^0
} T=V{3v@zs
$[cB6
UDcr5u eKn
} IWN18aaL?
S$wC{7?f
'i3-mZ/|8
O@HD'
w\Q(wH'
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。 Oa@SyroF=
mpDxJk!
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 8?EKF+.u|
Te)%L*X
做法如下: BgCEv"G5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,T 3M
V+0pvgS[
的信息,和一个结果集List: 6,~
%
java代码: /N/jwLr
@wAYhnxq
k-s|gC4
/*Created on 2005-6-13*/ cqZlpm$c
package com.adt.bo; 7I(QTc)*
<Z]j89wzDZ
import java.util.List; E){ODyk
(]fbCH:
import org.flyware.util.page.Page;
8rU| Oh
2Z^p)
/** 8193d%Wb
* @author Joa @1pfH\m
*/ KV{
publicclass Result { #f=41d%
0!:%Ge_
private Page page; 9dp4&&Z+F
2ss*&BR.
private List content; mSFA i
-=1>t3~\
/** cUi6 On1C
* The default constructor hG9Mp!d91
*/ h;cw=G
public Result(){ KUq(&H7
super(); ^\VVx:]
} ]nxSVKE4p
'2<N_)43$
/** }b<w \9AF
* The constructor using fields NZ^hp\q
* fE>JoQs38
* @param page =t}m
* @param content JkLpoe81
*/ eVbT<9k
public Result(Page page, List content){ e5n"(s"G*[
this.page = page; +rrA>~
this.content = content; {FN4BC`3+
} G)3r[C^[k
jR3mV
/** NPE 4@c_a@
* @return Returns the content. \)g}
*/ RM25]hx
publicList getContent(){ 9I1i(0q
return content; <{eJbN p
} %wJ>V-\e
N_0B[!B]
/** shY8h
* @return Returns the page. 1)-VlQK p
*/ skt9mU
public Page getPage(){ e&<=+\ul
return page; v+d`J55
} 1:I _;O_
j2hp*C'^
/** gb^'u
* @param content `7V'A
* The content to set. ^NxKA'oWQ
*/ fzjtaH?
public void setContent(List content){ 7zNfq.Ni~
this.content = content; r8_MIGM'
} l>7?B2^<E
ZZeF1y[q
/** W=K+kB
* @param page `my\59T
* The page to set. HIlTt
*/ 1HRcEzA
publicvoid setPage(Page page){ }%,LV]rGEZ
this.page = page; P[ ,
} T<0V ^B7
} kh"APxQ79
-ozcK
t0ZaI E
WsmP]i^Q
8/|1FI
2. 编写业务逻辑接口,并实现它(UserManager, 7 z+Ngt' !
+DSZ(Zb4qY
UserManagerImpl) @`SlOKz!=
java代码: 5%fR9?)
"(;t`,F
;Z&w"oSJ
/*Created on 2005-7-15*/ j|r$!gV
package com.adt.service; '81WogH:
_E^ !,Wz
import net.sf.hibernate.HibernateException; *Y ?&N2@c
x{VUl
import org.flyware.util.page.Page; %cq8%RT
5pxw[c53#
import com.adt.bo.Result; ~/Kqkhq+c
*nY$YwHB
/** S^SF!k=
* @author Joa ~:UAL}b{\~
*/ ~=Fp0l)#
publicinterface UserManager { Rdy-6
B,{Q[
public Result listUser(Page page)throws [g lhru=+
3=^B
&AB
HibernateException; 5e
c T.
6"o@d8>v
} ) !l1
v<]$,V]
e[.JS6
q{Gf@
ztaSIMZ
java代码: ^ Mq8jw(2
P)06<n1">Z
%T~LK=m
/*Created on 2005-7-15*/ +?C7(-U>
package com.adt.service.impl; 8wzQr2:
5S%#3YHY2
import java.util.List; }vX/55
#Gu(h(Z s
import net.sf.hibernate.HibernateException; vsbD>`I
-+ Mh('K
import org.flyware.util.page.Page; ~" U^N:I"
import org.flyware.util.page.PageUtil; lT F#efcW
XCE<].w
import com.adt.bo.Result; o:RO(oA0?
import com.adt.dao.UserDAO; ]Cc8[ZC
import com.adt.exception.ObjectNotFoundException; od]1:8OF
import com.adt.service.UserManager; x^!LA,`j
udX!R^8jE
/** NS^+n4
* @author Joa <ta#2
*/ qoJ<e`h}
publicclass UserManagerImpl implements UserManager {
k<
g
/cZ-+cu
private UserDAO userDAO; Wg=4`&F^
0/b3]{skK
/** qfB!)Y
* @param userDAO The userDAO to set. G\H |\i
*/ K]Z];C#)
publicvoid setUserDAO(UserDAO userDAO){
MVe4[<
this.userDAO = userDAO; \yA*)X+
} SQI =D8
{'q(a4
/* (non-Javadoc) -ob1_0
* @see com.adt.service.UserManager#listUser hkvymHaG
t;)`+K#1:
(org.flyware.util.page.Page) ,gn**E
*/ ~5wT|d
public Result listUser(Page page)throws @DCw(.k*
d?1[xv;
HibernateException, ObjectNotFoundException { 9
IY1"j0O
int totalRecords = userDAO.getUserCount(); iVf8M$!m
if(totalRecords == 0) 9':MD0P/M
throw new ObjectNotFoundException #~;:i
;Qdw$NuW
("userNotExist"); Te&5IB-
page = PageUtil.createPage(page, totalRecords); `EzC'e
List users = userDAO.getUserByPage(page); {~~'
returnnew Result(page, users); s7na!A[
} oD7^9=#
_[ufH*
} 4lF?s\W:
#P-T4R
|C.[eHe&D
APL #-`XC
TWo.c _l
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @hIHvLpRB
_If:~mIs
询,接下来编写UserDAO的代码: _D~FwF&A
3. UserDAO 和 UserDAOImpl: 3v:c'R0
java代码: oh^QW`#(
cR/z; *wr7
OE_A$8L
/*Created on 2005-7-15*/ ];au!
_o
package com.adt.dao; $Rv(v%
y,vrMWDy
import java.util.List; qb7ur;
E0<$zP}V}F
import org.flyware.util.page.Page; QB#rf='
e6hfgVN
import net.sf.hibernate.HibernateException; ~ YCZvJ
o_&*?k*
/** XXZ <r
* @author Joa xC.Tipn>
*/ "*0h=x$
publicinterface UserDAO extends BaseDAO { _t;Mi/\P
!d3:`l<
publicList getUserByName(String name)throws p+O,C{^f
WxI_wRKx
HibernateException; dI$M9;
R}Z2rbt
publicint getUserCount()throws HibernateException; |;(0]
6`sS8Ar&u
publicList getUserByPage(Page page)throws |GnqfD
{{ /-v3n
HibernateException; 1JSKK.LuJV
zkmfu~_)
} c:sk1I,d~^
>Yt+LdG!-
@6:J$B~)u
$z* Y:vFP
a) 5;Od
java代码: Vo:Gp
=hDFpb,mr
ZT%Q:]B+
/*Created on 2005-7-15*/ f%5 s8)
package com.adt.dao.impl; ?_Y2'O
VqK/GWg
import java.util.List; !_#2$J*s^D
/DN!"
import org.flyware.util.page.Page; 2C_/T8
*Z
C$DW!-
import net.sf.hibernate.HibernateException; Hlye:.$
import net.sf.hibernate.Query; J}3 7 9
bO\E)%zp
import com.adt.dao.UserDAO; a>XlkkX
$3Srr*
/** qJf=f3
* @author Joa :Vl2\H=P
*/ ;Alw`'
public class UserDAOImpl extends BaseDAOHibernateImpl m03]SF(#3
7z^\}&
implements UserDAO { t~@~XI5
w*7BiZ{s<
/* (non-Javadoc) 0)T`&u3!
* @see com.adt.dao.UserDAO#getUserByName Ed=]RR4R
25CO_
(java.lang.String) F9 q9BH
*/ F1UTj"<e
publicList getUserByName(String name)throws #>@~3kGg
b Q6<R4
HibernateException { dyMj=e
String querySentence = "FROM user in class [
bB
Dhy@!EOS
com.adt.po.User WHERE user.name=:name"; vgvJ6$#
Query query = getSession().createQuery rLzN#Zoi
xD3Y-d9
(querySentence); '2BE"e
query.setParameter("name", name); ( 17=|s
return query.list(); {#X]D~;s+
} 8O0E;6b
A,'JmF$d
/* (non-Javadoc) B>"O~ gZ{#
* @see com.adt.dao.UserDAO#getUserCount() 1hnw+T<<W
*/ xU_Dg56z'&
publicint getUserCount()throws HibernateException { 3iC$ "9!p
int count = 0; c[QXc9
String querySentence = "SELECT count(*) FROM Yl!~w:O!o
s#*T(pY
user in class com.adt.po.User"; \vQjTM-7
Query query = getSession().createQuery v;m}<3@'
pk,]yi,ZF
(querySentence); Yf=Puy}q
count = ((Integer)query.iterate().next 3Sb'){.MT+
,
e6}p
()).intValue(); //_aIp
return count; h<8.0
} ?rG>SA>o
q V+gQ
/* (non-Javadoc) D3BT>zTGK
* @see com.adt.dao.UserDAO#getUserByPage d5O_~xf&
rbw5.NU
(org.flyware.util.page.Page) JL1z8Nu
*/ eub2[,
publicList getUserByPage(Page page)throws 'ixu+.ZL/
VkChRzhC
HibernateException { 1>"[b8a/
String querySentence = "FROM user in class 9X- w5$<
sWc_,[b
com.adt.po.User"; s
v}o%
Query query = getSession().createQuery eAPNF?0yh
CCQ38P@rv
(querySentence); a\BV%'Zqg
query.setFirstResult(page.getBeginIndex()) fI([vI
.setMaxResults(page.getEveryPage()); ~&
@UH
return query.list(); 71GyMtX
} #-*#? -
^OWA
} '!wI8f
tDk !]
wVms"U.
`$5 QTte
Arzyq_ Yk
至此,一个完整的分页程序完成。前台的只需要调用 v==b.
2=
{-fhp@;
userManager.listUser(page)即可得到一个Page对象和结果集对象 m\hzQ9
?Dr K2;q
的综合体,而传入的参数page对象则可以由前台传入,如果用 --}5%6
!iO%?nW;
webwork,甚至可以直接在配置文件中指定。 6yN8(&`
SZhW)0
下面给出一个webwork调用示例: #2~-I
java代码: th?w&;L
{#,eD
RrG5`2
/*Created on 2005-6-17*/ 7i$)iNW
package com.adt.action.user; sOY+X
f0lpwwe
import java.util.List; |pA
g$N/pg2>cT
import org.apache.commons.logging.Log; [10y 13
import org.apache.commons.logging.LogFactory; TOe=6Z5h
import org.flyware.util.page.Page; /#C}1emK
sBLf(Q,
import com.adt.bo.Result; Mt93YD-2+
import com.adt.service.UserService; :~Z-K\
import com.opensymphony.xwork.Action; }CCTz0[D"
H>qw@JiO!
/** 'Cv>V"X: `
* @author Joa Uf
?._&:
*/ 9
Y-y?Y
publicclass ListUser implementsAction{ J:!m49fF
p!OCF]r
privatestaticfinal Log logger = LogFactory.getLog abW[hp
ruKm_j#J
(ListUser.class); +=:*[JEK,U
'kC,pN{->
private UserService userService; N-9Vx#i
Sl!#!FGI
private Page page; /YLHg5n8+
2.>WR~\
privateList users; Sz_{ #-
Z?);^m|T
/* o;zU;pkB
* (non-Javadoc) @|jLw($Ly
* |K(2_Wp
* @see com.opensymphony.xwork.Action#execute() |g@n'^]
*/ 5C|Y-G
publicString execute()throwsException{ T.}wcQf&*
Result result = userService.listUser(page); e@ mjh,
page = result.getPage(); `u't
users = result.getContent(); ~fV\
X*
return SUCCESS; ^]cl:m=*
} =,])xzG%
T{"[Ih3Mbl
/** E0s|eA&
* @return Returns the page. p";5J+?(
*/ aJ{-m@/5
public Page getPage(){ e}u68|\EC
return page; 1LK`
} EDA%qNd]j
wi gs1
/** q9h3/uTv
* @return Returns the users. AVnH|31dC~
*/ C+m%_6<
publicList getUsers(){ zFba("E Z
return users; %2;Nj;
J$
} @|2L>N
c;13V(Djy
/** ]VkM)< +
* @param page +QZ}c@'r
* The page to set. H:k?#7D(
*/ nr{#Krkb
publicvoid setPage(Page page){ i!a.6Gq
this.page = page; )/y7Fh
} 3 i;sB
y v58~w*"
/** mM $|cge"
* @param users ^ 5D%)@~
* The users to set. ..K@'*u
*/ -`8pahI
publicvoid setUsers(List users){ #hZ`r5GvTj
this.users = users; 7G\a5
} vH?rln
j&Trvw<t
/** 3n!f'" T
* @param userService x<'<E@jpU;
* The userService to set. 1
O?bT,"b
*/ @PZ{(
publicvoid setUserService(UserService userService){ 3!u`PIQv
this.userService = userService; wU5.t-|`
} V"Sa9P{y"
} !0Mx Bem
-\9K'8 C
EEn8]qJC
j6: jN-z
=`KA@~XH4
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ;xl0J*r
chE}TK
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 VrIR!9%:
r6QshCA"
么只需要: Ht"?ajW{
java代码: \:m1{+l
KPrH1 [VU
&|K9qa~)Y
<?xml version="1.0"?> `6:B0-r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork qI%X/'
Z_h-5VU-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- j2RdBoCt
0sA+5*mdM
1.0.dtd"> KSAE!+
p>l:^-N;f
<xwork> I'E7mb<2
{ew;
/;
<package name="user" extends="webwork- 4o<rj4G>
#I"s{*
interceptors"> _M)
G
2j;9USZ
p
<!-- The default interceptor stack name %#<MCiaK
|Zk2]eUO+
--> y}U}AUt
<default-interceptor-ref sR4B/1'E
h5Ee*De
name="myDefaultWebStack"/> >i_ #q$o
x^79s_h5
<action name="listUser" 7tP%tp
ez
lv>^P>S(O
class="com.adt.action.user.ListUser"> bn%4s[CVb4
<param +P=IkbxAO
.|e8v _2J
name="page.everyPage">10</param> kW7$Gw]-
<result 4:9N]1JCb
mIZ6[ ?
name="success">/user/user_list.jsp</result> :2.<JUDM
</action> 0T7t.
z*UgRLKZD
</package> )*XD"-9
v&qL r+_7
</xwork> 2e9.U/9
ifcp!l+8
?2%;VKN4
a*&(cn
;pw9+zo^M
v`@NwH<r
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 /Nkxb&
.b?Aq^i8
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 5P{[8PZxbV
cLf<YF
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `W:z#uNG]
~1&WR`U
Ew JNpecX
TM5 Y(Q*
EsS$th)d
我写的一个用于分页的类,用了泛型了,hoho P1R5}i
2){O&8 A
java代码: PJYUD5
\U3v5|Q
?<` ;lu/eL
package com.intokr.util; ~F^tLi!5
M1icj~Jr
import java.util.List;
!zfKj0^
/i~x.i3
/** zI0d
* 用于分页的类<br> S Rk%BJ? ~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> NBL%5!'
* H:)_;k
* @version 0.01 @^Rl{p
* @author cheng UM/!dt}DnF
*/ {;N2 &S o
public class Paginator<E> { uM\5GK
privateint count = 0; // 总记录数 -xG6J.S
privateint p = 1; // 页编号 Bi2 c5[3
privateint num = 20; // 每页的记录数 sh R|
privateList<E> results = null; // 结果 K3Bw3j 9
e#)NYcr6
/** P{x6e/
* 结果总数 %Zp|1J'"
*/ \Si p
publicint getCount(){ ?qb35
return count; inFS99DKx
} l/,la]!T
qW`?,N)r
publicvoid setCount(int count){ fwvwmZW
this.count = count; !1=*"H%t
} v;`>pCal
U.5R3z
/** =Oq*9=v|
* 本结果所在的页码,从1开始 T(qTipq0
* ;:&|DN3;
* @return Returns the pageNo. QWnGolN
*/ vz~Oi
publicint getP(){ @mJ~?d95v
return p; Mg2 e0}{
} z)(W
x">
Rx.v/H
/** C5~n^I|
* if(p<=0) p=1 r6nnRN/S=
* :w-:B^VB
* @param p $}.+}'7$
*/ 1+gF fKq
publicvoid setP(int p){ |;7mDhj=
if(p <= 0) b8_F2
p = 1; |j-ng;
this.p = p; $_iE^zZaU^
} 4&=</ok6`0
JEk'2Htx
/** <:Mz2Rg
* 每页记录数量 aU~?&]
*/ E%DT;1
publicint getNum(){ qY$ [2]
return num; ]
j8bv3
} d!UxFY@
co~NXpqg
/** yQ$]`hr;
* if(num<1) num=1 uorX;yekC
*/ %S"85#R5E
publicvoid setNum(int num){ tRpY+s~Fq
if(num < 1) k qL.ZR
num = 1;
4g"%?xN
this.num = num; x(cv}#}S8
} ,~=]3qmbR
- om9 Z0e
/** 0ki- /{;
* 获得总页数 XPU>} 4{
*/ |1"&[ .
publicint getPageNum(){ EG`6T
return(count - 1) / num + 1; k#zDY*kj
} 9(J,&)J
n|{#5#
/** SDC'S]{ew
* 获得本页的开始编号,为 (p-1)*num+1 -iS^VzI|I
*/ ^?Mp(o
publicint getStart(){ *!ng)3#
return(p - 1) * num + 1; Ku%tM7 ad
} Ny^f'tsA
}%8ZN :
/** 0cE9O9kE
* @return Returns the results. 0U@#&pUc
*/ }L)[>
publicList<E> getResults(){ GTM0Qvf?
return results; u\Ylo.)b
} $TmEVC^0
vMB61 |O
public void setResults(List<E> results){ y $\tqQ
this.results = results; 8W{M}>;[9
} HWsV_VAw}
50QDqC-]XS
public String toString(){ W`_JERo
StringBuilder buff = new StringBuilder 7H5VzV
jkx>o?s)z
(); Zs
/>_w}
buff.append("{"); dI
,A;.
buff.append("count:").append(count); UuWIT3W>%
buff.append(",p:").append(p); _i}b]xfM
buff.append(",nump:").append(num); o 2Nu@^+
buff.append(",results:").append 0#9H;j<Op
wKLYyetM!
(results); e{@RBYX@+c
buff.append("}"); J`U]Ux/L
return buff.toString(); *,4rYb7I w
} W|m(Jh[w]
qC> tni%
} Vo@7G@7K(
Yi%lWbr
(|K+1R