Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Vin d\yvM
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 94"R&|
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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 ]>K%,}PS
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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 ,dKcxp~[
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分页支持类: JI5?,
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java代码: %"@KuqV
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package com.javaeye.common.util; =kohQ d.n
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import java.util.List; 9}t2OJS*h"
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publicclass PaginationSupport { t#oJr2
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publicfinalstaticint PAGESIZE = 30; H-?SlVsf
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privateint pageSize = PAGESIZE; EP7L5GZ-a
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privateList items; <LQwH23@
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privateint totalCount; -uN5DJSW
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privateint[] indexes = newint[0]; _OP75kv
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privateint startIndex = 0; %v:9_nwO)
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public PaginationSupport(List items, int r8+{HknB;
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totalCount){ LnvC{#TFO
setPageSize(PAGESIZE); s$J0^8Q~i
setTotalCount(totalCount); JC}y{R8
setItems(items); D_D<N(O
setStartIndex(0); X'e@(I!0
} 1Ah
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public PaginationSupport(List items, int Rer\='
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totalCount, int startIndex){ W"YFx*W
setPageSize(PAGESIZE); uG&xtN8
setTotalCount(totalCount); 8a|p`)lT
setItems(items); s2riayM9/
setStartIndex(startIndex); [Hy0j*
} u!?.vx<qy
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public PaginationSupport(List items, int GUE3|
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totalCount, int pageSize, int startIndex){ wz31e!/
setPageSize(pageSize); 6",1JH,;p
setTotalCount(totalCount); <i`Ipj
setItems(items); =l&7~
setStartIndex(startIndex); y} AkF2:
} I0sd%'Ht?
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publicList getItems(){ O8TAc]B
return items; Wcl@H @
} wqJ^tA!
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publicvoid setItems(List items){ gI6./;;x
this.items = items; p ElF,Y
} D`,W1Z#
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publicint getPageSize(){ 3i=+ [
return pageSize; fmY=SqQG-
} F#eZfj~
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publicvoid setPageSize(int pageSize){ 'J#u;KJ
this.pageSize = pageSize; E$=!l{Ms
} lNowH0K!D
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publicint getTotalCount(){ !"j?dQ.U;
return totalCount; v4=9T<[
} ComVY4,
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publicvoid setTotalCount(int totalCount){ 1|l'oTAA
if(totalCount > 0){ Y` Oz\W
this.totalCount = totalCount; 9lNO
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int count = totalCount / lX/s Q
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h
pageSize; d4t%/ Uh
if(totalCount % pageSize > 0) }&Ngh4/
count++; }p$>V,u
indexes = newint[count]; A
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for(int i = 0; i < count; i++){ thIuK V{CO
indexes = pageSize * pca `nN!
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} 3#`_t :"A
}else{ C|bnUN
this.totalCount = 0; x>d,\{U
} zBtlkBPu
} P!3)-apP\
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publicint[] getIndexes(){ DKnjmZ:J|
return indexes; _TY9!:&}q
} {DJ!T
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publicvoid setIndexes(int[] indexes){ S\b[Bq
this.indexes = indexes; CtJ*:wF
} F=!p7msRB
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publicint getStartIndex(){ 0+%{1JkJq
return startIndex; q">lP(t
} *UhYX)J
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publicvoid setStartIndex(int startIndex){ UJMM&
if(totalCount <= 0) s.`:9nj
this.startIndex = 0; t>"UenJt-
elseif(startIndex >= totalCount) P|HxD0c^u
this.startIndex = indexes e=&,jg?K
8Q
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[indexes.length - 1]; `ECT8
elseif(startIndex < 0) ZmeSm&
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this.startIndex = 0; _rt+OzZ*L
else{ hAX@|G.
this.startIndex = indexes jLo(Uf
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[startIndex / pageSize]; r0t4\d_&
} ^=`7]E [p
} 1=:=zyEEo
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publicint getNextIndex(){ 7.mY@
int nextIndex = getStartIndex() + CAg~K[
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pageSize; 1c8Nr&Jl
if(nextIndex >= totalCount) E#}OIZ\S
return getStartIndex(); #0>??]&r
else }#):ZPTs
return nextIndex; 3kfrOf.4h
} S"hA@j
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publicint getPreviousIndex(){ xe?!UCUb@
int previousIndex = getStartIndex() - d1CQ;,Df<
@9#l3
pageSize; ~+DPq|-O
if(previousIndex < 0) j"=F\S&!
return0; S;@nPzhc
else vDI$
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return previousIndex; t7GK\B8:
} 1%Hc/N-
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} ayF+2(vch)
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抽象业务类 p1tqwV
java代码: IE*eDj
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/** #<h//<
* Created on 2005-7-12 +}3l$L'bY
*/ u7||]|2
package com.javaeye.common.business; PY81MTv0;
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import java.io.Serializable; %M)LC>c
import java.util.List; rnAQwm-8O%
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import org.hibernate.Criteria; fh%|6k?#M
import org.hibernate.HibernateException; U]Y</>xGI
import org.hibernate.Session; Yzr)UJl*I
import org.hibernate.criterion.DetachedCriteria; -sjyv/%_
import org.hibernate.criterion.Projections; 7b8+"5~
import '#<4oW\]
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org.springframework.orm.hibernate3.HibernateCallback; #hMS?F|
import P;8nC:z L
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org.springframework.orm.hibernate3.support.HibernateDaoS WwDd62g
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upport; ohU}ST:9
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import com.javaeye.common.util.PaginationSupport; X!xmto
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public abstract class AbstractManager extends E.N@qMn~
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HibernateDaoSupport { C))x#P36
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privateboolean cacheQueries = false; !jWE^@P/B
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privateString queryCacheRegion; ?lca#@f(
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publicvoid setCacheQueries(boolean C'7DG\pr
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cacheQueries){ c/DK31K
this.cacheQueries = cacheQueries; 3\}>nE
} Z% DJ{!Hnh
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publicvoid setQueryCacheRegion(String %?hvN
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queryCacheRegion){ baoyU#X9
this.queryCacheRegion = ${)oi:K@:
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queryCacheRegion; riZ :#I
} 5OCt Q4u
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publicvoid save(finalObject entity){ h! Bg}B~
getHibernateTemplate().save(entity); OO2uE ;( 3
} VqUCcT
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publicvoid persist(finalObject entity){ GT7&>}FJ)
getHibernateTemplate().save(entity); ck< `kJ`b
} P;`Awp?
< 1%}8t"
publicvoid update(finalObject entity){ K491QXG
getHibernateTemplate().update(entity); +MZI \>
} uPq@6,+
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publicvoid delete(finalObject entity){ {O:{F?
getHibernateTemplate().delete(entity); ;W T<]
} >F>VlRg
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publicObject load(finalClass entity, "O'c.v?{x
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finalSerializable id){ HSWki';G
return getHibernateTemplate().load 80=LT-%#
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(entity, id); $%^](-
} 'ieTt_1.G
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publicObject get(finalClass entity, ohbU~R3{U
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finalSerializable id){ zYP6m3n
return getHibernateTemplate().get D>8p:^3g
<(@Z#%O9)
(entity, id); >|z:CX$]
} gxhdxSm=2
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publicList findAll(finalClass entity){ ]ag{sU@#
return getHibernateTemplate().find("from fgs@oaoZ
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" + entity.getName()); ^.R!sQ
} QJj='+R>
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publicList findByNamedQuery(finalString W+GC3W
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namedQuery){ L}CU"
return getHibernateTemplate ImG8v[Q
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().findByNamedQuery(namedQuery); Y6&v&dA;
} PJ;WNo8
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publicList findByNamedQuery(finalString query, ]\KVA)\
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finalObject parameter){ aoZ |@x
return getHibernateTemplate p5$}h,7
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().findByNamedQuery(query, parameter); c+&Kq.~K
} zt:
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publicList findByNamedQuery(finalString query, jhf#
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finalObject[] parameters){ \HbZ~I-
return getHibernateTemplate "o+?vx-
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().findByNamedQuery(query, parameters); F$DA/ {.D
} pH mqwB~|
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publicList find(finalString query){ '=vZAV`
return getHibernateTemplate().find )M.s<Y
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(query); L~-/'+
} 'bJGQ[c
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publicList find(finalString query, finalObject 6`O,mpPu4G
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parameter){
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return getHibernateTemplate().find L4Zt4Yuw
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(query, parameter); aaig1#a@1b
} tO{{ci$-T
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public PaginationSupport findPageByCriteria f]8MdYX(
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(final DetachedCriteria detachedCriteria){ $uHQl#!;
return findPageByCriteria }lIc{R@H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); a$|U4Eqo
} v1 8<~
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public PaginationSupport findPageByCriteria U;#KFZ+~
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(final DetachedCriteria detachedCriteria, finalint fgd2jr3T
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startIndex){ 8{jXSCP#
return findPageByCriteria ).^d3Kp
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(detachedCriteria, PaginationSupport.PAGESIZE, Cw+boB_tip
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startIndex); (U.Go/A#wE
} SvM\9
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public PaginationSupport findPageByCriteria LZn'+{\`
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(final DetachedCriteria detachedCriteria, finalint k`m7j[A]l
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pageSize, )$:1e)d
finalint startIndex){ pq{`WgA^
return(PaginationSupport) f\hMTebma$
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getHibernateTemplate().execute(new HibernateCallback(){ tLy:F*1i
publicObject doInHibernate ,,{;G'R|
0 #8
(Session session)throws HibernateException { @GN2v,WA?
Criteria criteria = 49MEGl;K0\
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detachedCriteria.getExecutableCriteria(session); T'5{p
int totalCount = 3^UdB9j;
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((Integer) criteria.setProjection(Projections.rowCount !1)aie+p6
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()).uniqueResult()).intValue(); ">bhxXeiN
criteria.setProjection M1kA- Xr
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(null); N[/<xW~x?4
List items = Ks%0!X?3q
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criteria.setFirstResult(startIndex).setMaxResults 6HY): M&?
eq6O6-
(pageSize).list(); ~*iF`T6
PaginationSupport ps = sC-o'13
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new PaginationSupport(items, totalCount, pageSize, C^)Imr
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startIndex); cdMSC7l!
return ps; |owr?tC
} O@Aazc5K
}, true); p1KhI;^
} qi,) l*?f
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public List findAllByCriteria(final y*iZ;Bv j
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DetachedCriteria detachedCriteria){ >G5aFk
return(List) getHibernateTemplate yvB]rz} i
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().execute(new HibernateCallback(){ =d{6=2Pt
publicObject doInHibernate 4zMvHe
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(Session session)throws HibernateException { 40kAGs>_
Criteria criteria = i6if\B
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detachedCriteria.getExecutableCriteria(session); 60+ zoL'
return criteria.list(); jSem/;
} +_]Ui| l
}, true); (]#^q8)]\9
} /I 7V\
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public int getCountByCriteria(final c u/"=]D
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DetachedCriteria detachedCriteria){ W;OGdAa_
Integer count = (Integer) _EMI%P&s
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getHibernateTemplate().execute(new HibernateCallback(){ GeR#B;{
publicObject doInHibernate ?Q]&;5o
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(Session session)throws HibernateException { FSEf0@O:
Criteria criteria = W> pe-
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detachedCriteria.getExecutableCriteria(session); rRe5Q
return f-F=!^.
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criteria.setProjection(Projections.rowCount {lds?AuK
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()).uniqueResult(); #`SAc`:n
} f+ r>ur}\)
}, true); ew1L+
return count.intValue(); R{@saa5I(>
} UdO8KD#r3
} SP%X@~d
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 MJ:c";KCq0
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PaginationSupport的实例ps。 mE<_oRM)
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ps.getItems()得到已分页好的结果集 84(Jo_9
ps.getIndexes()得到分页索引的数组 (@^9oN~}
ps.getTotalCount()得到总结果数 Oa/^A-'Q
ps.getStartIndex()当前分页索引 +p\E%<uQ
ps.getNextIndex()下一页索引 ;?Pz0,{h
ps.getPreviousIndex()上一页索引 1n`[D&?q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 KGgtEh|
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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 ]t0o%w
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一下代码重构了。 uc,>VzdB
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我把原本我的做法也提供出来供大家讨论吧: Mq91HmC(@
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首先,为了实现分页查询,我封装了一个Page类: Q`bXsH
java代码: 5p.rd0T]l3
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/*Created on 2005-4-14*/ H>+/k-n-
package org.flyware.util.page; 8#QT[H
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/** %wbdg&^
* @author Joa :j]6vp6
* ,ojJ;w5D
*/ ]G[ "TX,
publicclass Page { 5RLO}Vn]
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/** imply if the page has previous page */ sPK ]:iC
privateboolean hasPrePage; 1sXCu|\q
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/** imply if the page has next page */ "W5MZ
privateboolean hasNextPage; I!/EQO|
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/** the number of every page */ .w4|$.H
privateint everyPage;
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/** the total page number */ dg|+?M^9`
privateint totalPage; g+o$&'\
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/** the number of current page */ qK'mF#n0#
privateint currentPage; s`x2Go
e, sS.
/** the begin index of the records by the current ^$oa`B^2JM
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query */ ]:f.="
privateint beginIndex; ^?e[$}
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/** The default constructor */ cs2-jbRn
public Page(){ 72|g zm
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} z"6o|]9I
z_(l]Ern}
/** construct the page by everyPage #Shy^58$
* @param everyPage jO"/5x26
* */ +/&rO,Ql
public Page(int everyPage){ @C-dCC?
this.everyPage = everyPage; m !:F/?B
} Ps0Cc _
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/** The whole constructor */ D0#U*tq;
public Page(boolean hasPrePage, boolean hasNextPage,
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int everyPage, int totalPage, ]Z[3 \~?
int currentPage, int beginIndex){ ULew ~j
this.hasPrePage = hasPrePage; U$D:gZ
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; A#$l;M.3R
this.totalPage = totalPage; '0f!o&?g
this.currentPage = currentPage; EW]DzL3
this.beginIndex = beginIndex; >0kL9_9{
} <2*+Y|Lk2
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/** e[k\VYj[
* @return 0uKm)t/
* Returns the beginIndex. Rq15AR
*/ 4P Sbr$
publicint getBeginIndex(){ k&yBB%g
return beginIndex; PM*lnd#J
} wOUCe#P|r
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/** :TrP3wV_
* @param beginIndex o
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* The beginIndex to set. +2E~=xX
*/ ~ DLxIe
publicvoid setBeginIndex(int beginIndex){ r(]Gd`]
this.beginIndex = beginIndex; U;&s=M0[
} d>M 0:
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/** lN.&46
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* @return F\+9u$=
* Returns the currentPage. #5;4O{
*/ gd3MP^O1
publicint getCurrentPage(){ /pe.?Zd
return currentPage; MXVCu"g%
} %_]O|(
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/** -XECYwTh
* @param currentPage +L?;g pVE&
* The currentPage to set. = r=/L
*/ B%Oi1bO
publicvoid setCurrentPage(int currentPage){ -b%' K}.C
this.currentPage = currentPage; 6#d+BBKIc
} Md:*[]<~
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/** )$Fw<;4
* @return @6 jKjI
* Returns the everyPage. ;).QhHeg>
*/ 7B _Wz9y
publicint getEveryPage(){ 5;{*mJ:F
return everyPage; Wi)N/^;n
} !H^R_GC
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/** #I yM`YB0
* @param everyPage Gd&G*x
* The everyPage to set. 1g!%ej
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*/ GB>h8yXH
publicvoid setEveryPage(int everyPage){ +],2smd@N
this.everyPage = everyPage; ~}YgZ/U7T
} "(F:'J} X
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/** 7Il
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* @return .@(MNq{"6
* Returns the hasNextPage. _#U hXXD
*/ z<"\I60Fe
publicboolean getHasNextPage(){ U,/9fzgd
return hasNextPage; ;hDIoSz
} $>~4RXC
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/** T7G{)wm
* @param hasNextPage 6l?KX
* The hasNextPage to set. >*w(YB]/$V
*/ d cht8nX7~
publicvoid setHasNextPage(boolean hasNextPage){ tIX|oWC$q
this.hasNextPage = hasNextPage; =WOYZ7
} ,J-YfL^x6*
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/** JENq?$S
* @return `Oi6o[a
* Returns the hasPrePage. n@e|PWu
*/ a67NWH
publicboolean getHasPrePage(){ Xo4K!U>TzZ
return hasPrePage; fl9J
} N'5!4JUI
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/** {u7_<G7
* @param hasPrePage [ \i1I`7pE
* The hasPrePage to set. Q5v_^O<!
*/ bF3}L=z
publicvoid setHasPrePage(boolean hasPrePage){ @6DV?VL
this.hasPrePage = hasPrePage; -,xsUw4
} My>{;n=}
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/** 0Z[8d0
* @return Returns the totalPage. i3y>@$fRL\
* 'v3>"b
*/ ZYW=#df R
publicint getTotalPage(){ Oz,/y3_
return totalPage; a_(vpD^
} ;l b@o,R :
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/** zwX1&rN
* @param totalPage w0t||qj^>"
* The totalPage to set. 4THGHS^
*/ ?Da!QH
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publicvoid setTotalPage(int totalPage){ 8BJ&"y8H
this.totalPage = totalPage; 3m`y?Dd
} [^-DFq5@
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} hI1}^;
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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 $'VFb=?XrK
'%9e8C|
个PageUtil,负责对Page对象进行构造: q>ps99[=
java代码: tm}0kWx
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/*Created on 2005-4-14*/ fL&bN[XA"$
package org.flyware.util.page; J4ltHk.|
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import org.apache.commons.logging.Log; viY &D
import org.apache.commons.logging.LogFactory; MkG*6A
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/** `=3:*.T*
* @author Joa 4jl-?
* Ik4U+'z6
*/ &<sDbNS
publicclass PageUtil { j!P]xl0vOZ
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privatestaticfinal Log logger = LogFactory.getLog paW7.~3
R
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(PageUtil.class); oUBn:Ir@
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/** 7.l[tKh
* Use the origin page to create a new page B@Q Ate7
* @param page 4`7:gfrO,
* @param totalRecords h~
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* @return ]MP6VT
*/ @ zE>n
publicstatic Page createPage(Page page, int x;Jy-hMNl
xV4
#_1(
totalRecords){ dw!cDfT+
return createPage(page.getEveryPage(), >h7qI-
2 -uL
page.getCurrentPage(), totalRecords); LMrb
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} i7f/r.
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/** Xo>P?^c4?
* the basic page utils not including exception 0ZXG{Gp9S
$>;U^- #3
handler PI#xRKt
* @param everyPage _$?SK id|o
* @param currentPage 8I'c83w
* @param totalRecords <OcD [5
* @return page jR#g>MDKB
*/ O#E]a<N`
publicstatic Page createPage(int everyPage, int /K"koV;
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currentPage, int totalRecords){ iy{*w&p
everyPage = getEveryPage(everyPage); _kb
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currentPage = getCurrentPage(currentPage); A-&C.g
int beginIndex = getBeginIndex(everyPage, io$!z=W
r-+ .Ax4L"
currentPage); z17x%jXy
int totalPage = getTotalPage(everyPage, 1#9 Q1@'OS
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totalRecords); &C+pen)Z
boolean hasNextPage = hasNextPage(currentPage, nxP>IfSA
9air"4
totalPage); hSq3LoHV
boolean hasPrePage = hasPrePage(currentPage); sV+/JDl
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returnnew Page(hasPrePage, hasNextPage, <3iL5}
everyPage, totalPage, R;gN^Yjk:
currentPage, 0S0 ?\r
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beginIndex); +.T&U7xV
} wPYz&&W
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privatestaticint getEveryPage(int everyPage){ vJT
%ET
return everyPage == 0 ? 10 : everyPage; t3.;W/0_
} vcnUb$%
k1HukGa
privatestaticint getCurrentPage(int currentPage){ pzP~,cdf
return currentPage == 0 ? 1 : currentPage; iXt >!f*
} gf^"sfNk
@54D<Lj
privatestaticint getBeginIndex(int everyPage, int hTZaI *
pDO&I]S`q0
currentPage){ (5] |Kcp|
return(currentPage - 1) * everyPage; Rw\
LVRdA
} p`)(
#`rvL6W q}
privatestaticint getTotalPage(int everyPage, int EM+#h'%-
L<encPJt
totalRecords){ JB~79Lsdz
int totalPage = 0; NWuS/Ur`9
"MD
if(totalRecords % everyPage == 0) UUGwXq96i
totalPage = totalRecords / everyPage; Iq`:h&'!L
else A"8`5qa
totalPage = totalRecords / everyPage + 1 ; ,c#=qb8""
8*;88vW"2
return totalPage; sG`:mc~0
} q$Z.5EN
2XubM+6
privatestaticboolean hasPrePage(int currentPage){ x,a(O@
return currentPage == 1 ? false : true; 2B{~"<
} tY^ MP5*
<J4|FOz!=
privatestaticboolean hasNextPage(int currentPage, %]Gm
wiXdb[[#
int totalPage){ 8_6\>hW&
return currentPage == totalPage || totalPage == e#MEDjm/)g
S+G!o]&2
0 ? false : true; C~F do0D
} p}%T`e=Z9
01VEz
8[\
M[N$N`9
} B:om61Dn
`x2Q:&.H`
r]p
0O(
(a0q*iC%
5T)qn`%
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。 y -j3d)T
SnsOuC5Ah
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 kYBy\
t(YrF,
做法如下: j^
VAA\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _zq"<Q c
zrWkz3FN
的信息,和一个结果集List: T >XnVK
java代码: Zi5d"V[}T
IKx]?0sS
/ E~)xgPM<
/*Created on 2005-6-13*/ =c
3;@CO
package com.adt.bo; Ww&~ZZZ {
8.4 1EKr2
import java.util.List; !iBe/yb
Sq"O<FmI
import org.flyware.util.page.Page; *5'U3py
cs[_5r&:
/** SXfuPM
* @author Joa B -XM(Cj
*/ z DDvXz
publicclass Result { 5}d"nx
}!=}g|z#|
private Page page; +cS%b}O`$
-F.A1{l[.
private List content; *GxOiv7"4W
ag Za+a
/** UruD&=AMK
* The default constructor es}j6A1
*/ EHk(\1!V
public Result(){ cNX,%
super(); nA:\G":\y
} j{00iA}
=WFn+#&^
/** i7g+8zd8d
* The constructor using fields Id`?yt
* _&!%yW@
* @param page <i9pJGW
* @param content ~Pq(Ta
*/ d~B]s
public Result(Page page, List content){ "/ G^+u
this.page = page; f>$Ld1
this.content = content; ;Ml??B]C
} M{ #
)NG{iD{_]
/** %Z|]"=;6
* @return Returns the content. . C_\xb
*/ .kO!8Q-;%
publicList getContent(){ %n<u- {`
return content; MRzrZZ%LQ
} .I%p0ds1r
)aY^k|I
/** n{oRmw-
* @return Returns the page. +3B^e%`NPm
*/ N<bNJD}
public Page getPage(){ Pe_mX*0
return page; {=]1]IWt
} ub^v,S8O
uYW9kw>$
/** tEEeek(!
* @param content 99Jk<x
k
* The content to set. 0@;kD]Z
*/ ZZ 1s}TG
public void setContent(List content){ -&87nR(eW
this.content = content; VT.BHZ
} ^<L;"jl%
1eG@?~G
/** 4
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* @param page {4u8~whLp
* The page to set. d0(GE4+/
*/ BPAz.K Q
publicvoid setPage(Page page){ q0Rd^c
this.page = page; OE,uw2uaT
} a|B^%
} XRU^7@Ylks
9d ZE#l!Q
slSQ \;CDA
Qg]8~^Q<
`? ayc/TK
2. 编写业务逻辑接口,并实现它(UserManager, 8ut:cCrmg
b?&=gm%oU
UserManagerImpl) U'IJwGRP
java代码: W`zY\]
T*"15ppfk
ZSL:q%:.
/*Created on 2005-7-15*/ oS'M
package com.adt.service; bJ8~/d]+
DwTqj=l
import net.sf.hibernate.HibernateException; @D.]PZf
1iOQ8hD
import org.flyware.util.page.Page; Mp;yvatO
.BLF7>
M1
import com.adt.bo.Result; RfPRCIo
I"*;fdm
/** }@Mx@ S
* @author Joa
0>D:
*/ D8+68_BEM
publicinterface UserManager { ^Pc>/lY$Q%
0(9]m)e
public Result listUser(Page page)throws N7lWeF
yKR0]6ahA
HibernateException; .HTX7mA3
|.D_[QI
} t
>89(
k
1c=Roiq
xJ"CAg|B
{.7ve<K
,z}wR::%
java代码: o6e6Jw
Q>gU(
B"O5P>
/*Created on 2005-7-15*/ FrSeR9b
package com.adt.service.impl; a$p2I+lX
/f!_dJ^
import java.util.List; #k%3Ag
.ON+ (
#n
import net.sf.hibernate.HibernateException; vfT<%Kl!'
}K=TB}yY
import org.flyware.util.page.Page; J90q\_dY.
import org.flyware.util.page.PageUtil; J!p<oW)a!
I:;+n^N?
import com.adt.bo.Result; +zO]N&
import com.adt.dao.UserDAO; k0ItG?Cv
import com.adt.exception.ObjectNotFoundException; *\ECf.7jz
import com.adt.service.UserManager; !v>ew9
dgc&[
/** 2P}bG>M
* @author Joa U^$E'Q-VK
*/ -2*>`,Uu
publicclass UserManagerImpl implements UserManager { .6 T4 z7I
=,:K)
private UserDAO userDAO; ,2zKQ2z
X47!E
|*
/** X;EJ&g/
* @param userDAO The userDAO to set. |]ucHV
*/ )f*Iomp]@
publicvoid setUserDAO(UserDAO userDAO){ r+\/G{+=}
this.userDAO = userDAO; <GfVMD
} a%J/0'(d
?qT(3C9p
/* (non-Javadoc) w}k B6o]
* @see com.adt.service.UserManager#listUser ?r3e*qJGn
"c
Pz|~
(org.flyware.util.page.Page) QJXdb]Y^;
*/ 8/q*o>[?
public Result listUser(Page page)throws O@,i1ha%
*m&&1W_
HibernateException, ObjectNotFoundException { 4iBxPo(0
int totalRecords = userDAO.getUserCount(); !~JWYY
if(totalRecords == 0) JDhwN<0R
throw new ObjectNotFoundException j|4tiv>
rPTfpeqN)
("userNotExist"); 0yQe5i}
page = PageUtil.createPage(page, totalRecords); g
i4
List users = userDAO.getUserByPage(page); yq6LH
returnnew Result(page, users); 2OC dG
} RKe?.
[%~NM/xu<
} shK&2Noan
\=g!$
RV92qn
B
wE2x:Ge:
#W5Yw>$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /(zB0TEd
D_ ug-<QT
询,接下来编写UserDAO的代码: 3"tg+DncC
3. UserDAO 和 UserDAOImpl: 3-
)kwy6L
java代码: 9::YR;NY
{ _X#fq0}
3@HIpQM3
/*Created on 2005-7-15*/ t>oM%/H
package com.adt.dao; |"\lL9CT
W-XN4:,qI
import java.util.List; 8A_TIyh?
Y_lCcu#OA
import org.flyware.util.page.Page; Wa/geQE1<
mxhW|}_-j
import net.sf.hibernate.HibernateException; OfLM
7b,AQ9
/** G>j"cj
* @author Joa +V89J!7
*/ S41)l!+2
publicinterface UserDAO extends BaseDAO { f#c BQ~
=U_@zDD@V
publicList getUserByName(String name)throws I ,9~*^$
@`2ozi~lO
HibernateException; ] - h|]
c}\
d5R_L
publicint getUserCount()throws HibernateException; 0gi}"v
,s81rJ-
publicList getUserByPage(Page page)throws :|fl?{E
~,+[M-
HibernateException; 't ;/,+:V
g4T3?"xMB_
} FJlsWh4,6=
Xr)g
W7]mfy^
i59k"pNm
NN*Sb J0
java代码: >oB ?
yEnKUo[
2}@*Ki7
/*Created on 2005-7-15*/ KK .cDAR
package com.adt.dao.impl; s9kTuhoK
wEv*1y4
import java.util.List; rl41#6
a6 * Y%?
import org.flyware.util.page.Page; {cX7<7N
B8>FCF&}E
import net.sf.hibernate.HibernateException; 2nYiG)tg
import net.sf.hibernate.Query; roL]v\tr
^
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import com.adt.dao.UserDAO; XSls]o
s
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/** @US '{hO1p
* @author Joa AF
QnCl Of
*/ Q!M sy<v
public class UserDAOImpl extends BaseDAOHibernateImpl >sB=\
{<~s&EPd
implements UserDAO { X.:_"+I;
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/* (non-Javadoc) _i#@t7
* @see com.adt.dao.UserDAO#getUserByName Mj,2\ijNM
s+Cl
(java.lang.String) n9w j[t1/
*/ FBE @pd
publicList getUserByName(String name)throws ?|gGsm+
WMRYT"J?N]
HibernateException { 8UlB~fVg
String querySentence = "FROM user in class .Wd.)^?
/XbY<pj
com.adt.po.User WHERE user.name=:name"; EgCp:L{
Query query = getSession().createQuery mp muziH
8o%E&Jg:
(querySentence); M_|M&lR>
query.setParameter("name", name); )moo?Q
return query.list(); Py}!C@e
} rZb_1E<
l6yB_M
/* (non-Javadoc) `W
D*Q-&n
* @see com.adt.dao.UserDAO#getUserCount() @m }rQT
*/ 5IwX\
publicint getUserCount()throws HibernateException { `*|LI
int count = 0; H@Kl
String querySentence = "SELECT count(*) FROM zvWO4\
zS,%msT^A
user in class com.adt.po.User"; Y!Usce
Query query = getSession().createQuery (0O`A~M3
CvgPIrl
(querySentence); HFpjNR
count = ((Integer)query.iterate().next k
QB 1=c
*_}IeNc
()).intValue(); LS*{]@8q
return count; Sj,4=a
} m3h2/}%9`
1"*Nb5s
/* (non-Javadoc) U1OLI]P
* @see com.adt.dao.UserDAO#getUserByPage }6yxt9
q{jk.:;'
(org.flyware.util.page.Page)
qQ2
*/ :XNK-A W
publicList getUserByPage(Page page)throws 4'd;'SvF
}A)^XZ/
HibernateException { +5N^TnBtBL
String querySentence = "FROM user in class KzxW?Ji$S
mkKRC;
com.adt.po.User"; ZA 99vO
Query query = getSession().createQuery oX%PsS
<VauJB*R
(querySentence); #S/pYP`7
query.setFirstResult(page.getBeginIndex()) p
P_wBX
.setMaxResults(page.getEveryPage()); tF{{cd
return query.list(); D>!v_v6
} g: H[#I
B'P,?`
} btr x?k(
1o"y%*"
38zR\@'j]4
6x`\
J2x
od|N-R
至此,一个完整的分页程序完成。前台的只需要调用 D0,oml
}bj,&c
userManager.listUser(page)即可得到一个Page对象和结果集对象 )w3XN A_V
i2\\!s
的综合体,而传入的参数page对象则可以由前台传入,如果用 &km d<
+dPE!:
webwork,甚至可以直接在配置文件中指定。 c +"O\j'
{VrAh*#h
下面给出一个webwork调用示例: Vj9`[1}1Z
java代码: ~7eUt^SD;
qHcY
2LV
q?gQ
/*Created on 2005-6-17*/ ;mM\,
{Z
package com.adt.action.user; *$*nY [/5
iq[2H$
import java.util.List; o} bj!h]N
#I*ht0++
import org.apache.commons.logging.Log; 7csl1|U
import org.apache.commons.logging.LogFactory; /3"e3{uy
import org.flyware.util.page.Page; oIu,rjb
o
i,g
import com.adt.bo.Result; &
Q|f *T
import com.adt.service.UserService; iZVT% A+q
import com.opensymphony.xwork.Action; ;]8p:ME
H/ B^N,oi
/** CC]@`R5
* @author Joa Is#v6:#^
*/ 7J)Hwl
publicclass ListUser implementsAction{ yA`]%U((
[1[[$ Dr
privatestaticfinal Log logger = LogFactory.getLog <_FF~lj
JsoWaD
(ListUser.class); f;qKrw
z!uB&2C{k
private UserService userService; 55jY` b.
!:!@dC%8_
private Page page; ~O7cUsAi'
da7x 1n$D
privateList users; ]pucv!
jv?aB
/* k6 h^
* (non-Javadoc) 1v8:,!C
* dBi3ZCAF
* @see com.opensymphony.xwork.Action#execute() S+bWD7
*/ CUTEp/+
publicString execute()throwsException{ } cH"lppX
Result result = userService.listUser(page); SE7 (+r
page = result.getPage(); d}6AHS[
users = result.getContent(); rym\5
`)
return SUCCESS; L_CEY
} 3YZ3fhpw
/:c,v-
/** UmHJ/DI@
* @return Returns the page. !WVabdt
*/ MHzsxF|
public Page getPage(){ c# 4ZDjvm6
return page; w7]p9B
} [.yx2@W
PrYWha=c-
/** KE|u}M@v6
* @return Returns the users. &,gryBN
*/ ~d<`L[
publicList getUsers(){ iLQt9Hyk
return users; HS7
G_
} r^Rcjyc1
=;-ju@d
/** %RR|QY*
* @param page oqU#I~ -
* The page to set. -|iA!w#31
*/ }5c'ui!3H
publicvoid setPage(Page page){ eVNBhR}HS
this.page = page; t1_y1!uQ
} 7^Q$pT>
R~mMGz
/** i?s&\3--Y
* @param users 07WIa@Q
* The users to set. sN an"
*/ ~.y4
,-
publicvoid setUsers(List users){ Ph!NYi,
this.users = users; CIs1*:Q9
} t2%bHIG}
Nv$gKC6 ,G
/** 0:(dl@I)@
* @param userService a(t<eN>b!
* The userService to set. kjYO0!C
*/ !6i
publicvoid setUserService(UserService userService){ fw~%^*
this.userService = userService; [T?6~^m=
} :^.8 7>V7
} j$ i8@]
HFCFEamBMP
=.2cZwxX$
{m*J95[
If I$
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, 5'L}LT8p@
g7q]Vj
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 d4=u`2w
w"Y55EURB
么只需要: zyQEz#O
java代码: .6-o?=5
z&/
o
-<^Q2]PE;
<?xml version="1.0"?> ve/6-J!5Y.
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork dZ81\jdYv
hI#M {cz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5^qp&
^
cd5Zl
1.0.dtd"> \\pyu]z
(Y@|h%1W
<xwork> f(ec/0W
F$.s6Hh.
<package name="user" extends="webwork- )ZT0zIG
U=?"j-wN
interceptors"> $">NW&
i(
{qdhp_~^l
<!-- The default interceptor stack name ?fX8WRdh
rVW'KN
--> c!FjHlAnP
<default-interceptor-ref J_br%AG<p
H;8]GE2n
name="myDefaultWebStack"/> ^RDXX+
42[:s:
<action name="listUser" -Ce4px?3
@z?.P;f9#
class="com.adt.action.user.ListUser"> @x>2|`65Y
<param 03jBN2[!
5|={1Lp24g
name="page.everyPage">10</param> 0'2{[xF
<result :1
P VW9iT+c
name="success">/user/user_list.jsp</result> hl~F1"q)
</action> `-`iS?
_BA_lkN+D
</package> iSW73P;)
|*| a~t
</xwork> ':>*=&
1s\hJATfz
PSw+E';
<Q~7a
hF
xa^HU~
q`K-T_<
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 ?{Z0g+B1
I%WK*AORM
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。 5"]2@@b4
+>%+r
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $?Mz[X
Lj AIB(*
&_^<B7aC'k
W {/z-&
FPFYH?;$
我写的一个用于分页的类,用了泛型了,hoho C)kQi2T
F}4 0
java代码: x5Pt\/ow
6242qb
!`U<RlK7
package com.intokr.util; RN3D:b+
>mltE$|
import java.util.List; Q 8E~hgO
/Day5\Q#
/** {j@)sDMX
* 用于分页的类<br> ?b$zuJ]
* 可以用于传递查询的结果也可以用于传送查询的参数<br> BC[d={_-
* pU'sADC
* @version 0.01 ^( VB5p
* @author cheng P!ICno6[e
*/ i(kK!7W35
public class Paginator<E> { hjT1SW\I
privateint count = 0; // 总记录数 9m9=O&C~-<
privateint p = 1; // 页编号 *[YN|
privateint num = 20; // 每页的记录数 1"6k5wrIA
privateList<E> results = null; // 结果 8H b|'Q|^
'$^ F.2
/** J>PV{N
* 结果总数 Mdh"G @$n
*/ L`
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publicint getCount(){ B.WkHY%/
return count; j( :A
} jYZWf `X~
vw;
publicvoid setCount(int count){ >u2#<k]1&
this.count = count; @S92D6
} WcG&W>
Zi)8KO[/0
/** T480w6-@
* 本结果所在的页码,从1开始 PyF4uCn"H
* 7T Bo*-!
* @return Returns the pageNo. cyE2=
*/ C^tC} n1D(
publicint getP(){ _4]dPk#^
return p; l
d9#4D[#
} t1^96@m^
Xlw=R2`)~
/** 8[ OiG9b
* if(p<=0) p=1 2ow\d b
* Nf'9]I
* @param p Q1[s{,
*/ ?O?~|nI
publicvoid setP(int p){ bm.H0rHR4
if(p <= 0) QD~`UJe>
p = 1; b1o(CG(}*
this.p = p; !Esiq<Yh
} xGA0]
_
`pUArqf
/** o7seGw<$X
* 每页记录数量 ,;18:
*/ PBv43uIL
publicint getNum(){ VA.1JBQ
return num; }6N|+z.cU
} x6tY _lzJ
!W7ekPnK
/**
U8!njLC
* if(num<1) num=1 Hd`RR3J
*/ B)dynGF8i
publicvoid setNum(int num){ 2ZeL
if(num < 1) D
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num = 1; iH=@``Z
this.num = num; -;*Z!|e9
} Mw.+0R!T
w%\;|y4+
/** ZZ5yu* &
* 获得总页数 78-:hk
*/ quYZD6IH
publicint getPageNum(){ s#[Ej&2[=
return(count - 1) / num + 1; |O?Aj1g[c?
} o*xEaD
NM Ajt>t
/** 1<"kN^
* 获得本页的开始编号,为 (p-1)*num+1 xWm'E2
*/ ~/%){t/uLY
publicint getStart(){ 'z'm:|JW
return(p - 1) * num + 1; AtOB'=ph*
} RT>3\qhZ
ijB,Q>TgO
/** }2@$2YR[
* @return Returns the results.
dp"w=~53
*/ n6}1{\
publicList<E> getResults(){ W>y_q[m
return results; {UN z UaE
} ;xc
4
#N#[;M
public void setResults(List<E> results){ tWFJx}H
this.results = results; C@-JH\{\T#
} AUK7a
OjI*HC
public String toString(){ wF(FV4#gs
StringBuilder buff = new StringBuilder Yq_zlxd%F
i=4bY[y
(); Ow
I?(ruL'
buff.append("{"); u$"5SGI6
buff.append("count:").append(count); @b
zrJ7$
buff.append(",p:").append(p); DiX4wmQ
buff.append(",nump:").append(num); S]>_o "|HV
buff.append(",results:").append L[K_!^MZ
-*EJj>x
(results); bCF63(0
buff.append("}"); -1R~3j1_
return buff.toString(); i469<^A
} saV `-#
-h_v(s2
} SXL6)pX
9pgct6BO
F-Ea85/K@4