Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `Y-uNJ'.N
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 rp.S4;=Q 9
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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 ~a8J"Wh
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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 FS r`Y
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分页支持类: m,v"N%k,
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java代码: EN()dCQHr
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package com.javaeye.common.util; HH3WZ^0>
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import java.util.List; B&#TbKp
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publicclass PaginationSupport { 6pI=?g
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publicfinalstaticint PAGESIZE = 30; L$h.VQv+
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privateint pageSize = PAGESIZE; w-R>gdm
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privateList items; Nhn5 iN1*
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privateint totalCount; EXg\a#4['
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privateint[] indexes = newint[0]; to^ &:
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privateint startIndex = 0; Ob?>zsx
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public PaginationSupport(List items, int )h,+>U@
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totalCount){ <DiD8")4
setPageSize(PAGESIZE); N
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setTotalCount(totalCount); ' eO4h^
setItems(items); &}VGC=F;d
setStartIndex(0); ~Rk%M$E9
} ;14[)t$
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public PaginationSupport(List items, int zWgNDYT~
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totalCount, int startIndex){ q"'^W<i
setPageSize(PAGESIZE); C',D"
setTotalCount(totalCount); m>$+sMZE
setItems(items); dl@
setStartIndex(startIndex); ,2DKp hh
} oDTt+b
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public PaginationSupport(List items, int :#"gQ^YNp
/}r%DND'
totalCount, int pageSize, int startIndex){ \y{Bnp5h
setPageSize(pageSize); 9M:wUYHT
setTotalCount(totalCount); HQK%Y2S
setItems(items); gAC}
setStartIndex(startIndex); !E,$@mvd
} B cd6~
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publicList getItems(){ NTuS(7m
return items; BQmg$N,F
} zht^gOs
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publicvoid setItems(List items){ 7qV_QZ!.
this.items = items; bqN({p&
} xIf,1g@Cq9
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publicint getPageSize(){ Z_D8}$!
return pageSize; ~K 8eRT
} .JZoZ.FAb
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publicvoid setPageSize(int pageSize){ %+ig7a:
this.pageSize = pageSize; sAfSI<L_
} <w(UDZ
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publicint getTotalCount(){ J2Ocf&y;
return totalCount; EE#4,d`J
} SJ^.#^)
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publicvoid setTotalCount(int totalCount){ 6BRQX\
if(totalCount > 0){ 1bF aQ50t
this.totalCount = totalCount; >,Zjlkh3
int count = totalCount / u^|XQWR$:
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pageSize; LpeQx\
if(totalCount % pageSize > 0) l|^p;z:d
count++; 9XX&~GW/
indexes = newint[count]; nV,qC.z
for(int i = 0; i < count; i++){ ` QXO+'j4
indexes = pageSize * t8\F7F P
+'2Mj|d@p
i; gpVZZ:~
} Yvs)H'n=
}else{ *oL?R2#7
this.totalCount = 0; vXLiYWo
} 63QMv[`,
} f{FW7T}O2
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publicint[] getIndexes(){ {*ATY+
return indexes; wAkpk&R
} g+t-<D"L5
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publicvoid setIndexes(int[] indexes){ Yw"o_
this.indexes = indexes; }L>}_NV\
} @X?DHLM
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publicint getStartIndex(){ eZIqyw
return startIndex; ?<]BLkx
} a&6 3[p.<}
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publicvoid setStartIndex(int startIndex){ {3@f(H m
if(totalCount <= 0) v{$X2z_$w
this.startIndex = 0; /qed_w.p
elseif(startIndex >= totalCount) 57* z0<
this.startIndex = indexes #Gx%PQ`
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[indexes.length - 1]; R22YKXU
elseif(startIndex < 0) 7/a[;`i*!
this.startIndex = 0; S3EY9:^C
else{ _?M34&.X
this.startIndex = indexes tisSj ?+
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[startIndex / pageSize]; XxcY
} !qS~YA
} pYa8iQ`6U;
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publicint getNextIndex(){ B\r2M`N5
int nextIndex = getStartIndex() + J:Ea|tXK^
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pageSize; /17Qhex
if(nextIndex >= totalCount) VdjS\VYe,
return getStartIndex(); U<gMgA
else #( F/P!qk
return nextIndex; JS<S?j?*/
} <qT[
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publicint getPreviousIndex(){ 0_q8t!<xJw
int previousIndex = getStartIndex() - K'%2 'd
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pageSize; ;{EIx*<d
if(previousIndex < 0) }(A`aB_
return0; FkY}6
else X]8(_[Y
return previousIndex; Q^prHn*@
} aUa.!,_dh
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} g>-pC a
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抽象业务类 g = ~Y\$&
java代码: U$v|c%6
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/** `)%z k W
* Created on 2005-7-12 r+n0M';0
*/ <*EMcZ
package com.javaeye.common.business; ?!^ow5"8
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import java.io.Serializable; k>E^FB=
import java.util.List; fb-Lp#!T39
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import org.hibernate.Criteria; :dq.@:+<R
import org.hibernate.HibernateException; 94VtGg=b}
import org.hibernate.Session; J{;XNf =
import org.hibernate.criterion.DetachedCriteria; \ne1Xu:hM
import org.hibernate.criterion.Projections; g%Bh-O9\
import ve($l"T
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org.springframework.orm.hibernate3.HibernateCallback; 7]W6\Z
import 5;'(^z-bL
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org.springframework.orm.hibernate3.support.HibernateDaoS 'L?e)u.
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upport; \c}_!.xj"
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import com.javaeye.common.util.PaginationSupport; <}7 5Xo
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public abstract class AbstractManager extends _D~l2M
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HibernateDaoSupport { } I>6 8dS[
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privateboolean cacheQueries = false; 9d&@;&al
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privateString queryCacheRegion; ypU-/}Cf,
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publicvoid setCacheQueries(boolean '
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cacheQueries){ /T_{k.
this.cacheQueries = cacheQueries; L $L/5/
} yPY}b_W
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publicvoid setQueryCacheRegion(String ;)~}/nR<a
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queryCacheRegion){ YP
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this.queryCacheRegion = "5<:Dj/W
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queryCacheRegion; |w5m2Z
} S[ch/
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publicvoid save(finalObject entity){ "<Ozoo1&w
getHibernateTemplate().save(entity); L4O.= *P1
} fGZ56eH:
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publicvoid persist(finalObject entity){ E{;F4wT_@
getHibernateTemplate().save(entity); v[;R(pt?
} )
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publicvoid update(finalObject entity){ /H4Z.|@
getHibernateTemplate().update(entity); /RVwhA+c
} lfvt9!SJ+/
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publicvoid delete(finalObject entity){ Y5c,O>T5Y
getHibernateTemplate().delete(entity); R
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} rn^cajO^
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publicObject load(finalClass entity, D:] QBA)C
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finalSerializable id){ ZnKjU ]m
return getHibernateTemplate().load IG+g7kDCY
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ql
(entity, id); mT:NC'b<9
} vtq$@#?~ b
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publicObject get(finalClass entity, kEgpF{"%n
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finalSerializable id){ 7|5X> yt
return getHibernateTemplate().get rjffpU
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(entity, id); <%o9*)F
} dGyrzuPJ
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publicList findAll(finalClass entity){ 44NMof8N
return getHibernateTemplate().find("from Gv[s86AP,
1=Z!ZY}}e
" + entity.getName()); 2&"qNpPtE
} 7}:+Yx
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publicList findByNamedQuery(finalString q9:g
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namedQuery){ /#WvC;B
return getHibernateTemplate V7b;qC'
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().findByNamedQuery(namedQuery); Q,K$)bM
} ({ O~O5k
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publicList findByNamedQuery(finalString query, (xfh 9=.
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finalObject parameter){ }*
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return getHibernateTemplate KomMzG:
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().findByNamedQuery(query, parameter); fat;5XL@
} @ ]40xKF
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publicList findByNamedQuery(finalString query, E!'6vDVC:
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finalObject[] parameters){ Ur]/kij
return getHibernateTemplate o%bf7)~s
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().findByNamedQuery(query, parameters); 6Df*wi!jI
} h@E7wp1'~
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publicList find(finalString query){ ;L,i">_%u[
return getHibernateTemplate().find (3Q$)0t
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(query); u^G Y7gah
} )=#e*1!b
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publicList find(finalString query, finalObject j]FK.G'
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parameter){ ),CKuq>
return getHibernateTemplate().find ? cXW\A(
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(query, parameter); I_5/e>9
} U
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public PaginationSupport findPageByCriteria 76bMy4re
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(final DetachedCriteria detachedCriteria){ l$1NI#&
return findPageByCriteria m.p$f$A_
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); dQ:F 5|p
} P1AC2<H
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public PaginationSupport findPageByCriteria Vpne-PW
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(final DetachedCriteria detachedCriteria, finalint /o%VjP"<
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startIndex){ Cdy,8*
return findPageByCriteria >+Ig<}p
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(detachedCriteria, PaginationSupport.PAGESIZE, d)S`.Q
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startIndex); !ej]'>V,X
} O2\(:tvw
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public PaginationSupport findPageByCriteria ]=VRct
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(final DetachedCriteria detachedCriteria, finalint e'>q( B
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pageSize, aW*k,\:e
finalint startIndex){ Q?;Tc.O"/
return(PaginationSupport) ' Ut4=@)
)
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getHibernateTemplate().execute(new HibernateCallback(){ 3<Zp+rD
publicObject doInHibernate 5@%.wb4
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(Session session)throws HibernateException { {aN pk,n
Criteria criteria = R|}N"J _
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detachedCriteria.getExecutableCriteria(session); ymyzbE
int totalCount = 5L:-Xr{
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((Integer) criteria.setProjection(Projections.rowCount Nf^<pT[*
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()).uniqueResult()).intValue(); }^iqhUvT F
criteria.setProjection *2u~5Kc<
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(null); }dop]{RG
List items = EwX&Cj".
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criteria.setFirstResult(startIndex).setMaxResults vue^bn
*
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(pageSize).list(); \7i_2|w
PaginationSupport ps = ;<N:! $p
m)} 01N4
new PaginationSupport(items, totalCount, pageSize, tnaFbmp
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startIndex); ('SId@
return ps; Qw:!Rw,x
} |bz%SB
}, true); BaW4 s4u
} uZtN,Un
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public List findAllByCriteria(final 6_4B!
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DetachedCriteria detachedCriteria){ / n_s"[I4
return(List) getHibernateTemplate !}z'"l4i
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().execute(new HibernateCallback(){ iW^J>aKy
publicObject doInHibernate dgF%&*Il]O
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(Session session)throws HibernateException { }1e4u{
Criteria criteria = UPU$SZAIx
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detachedCriteria.getExecutableCriteria(session); HK8sn1j
return criteria.list(); gr SF}y!3
} GM0Q@`d
}, true); H:]cBk^[,
} {?eUAB<
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public int getCountByCriteria(final zk
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DetachedCriteria detachedCriteria){ *$ g!/,
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ ,< x/
publicObject doInHibernate *u1q7JFQk
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(Session session)throws HibernateException { VFL^-tXnA^
Criteria criteria = "vSKj/]
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detachedCriteria.getExecutableCriteria(session); 4}h}`KZZ
return yl~_~<s6
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criteria.setProjection(Projections.rowCount +Cw_qS"=
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()).uniqueResult(); )"pvF8JR%3
} R~4X?@ZB
}, true); Q!;syJBb.
return count.intValue(); 1j$\ 48Z
} O`9c!_lis
} gHLI>ew*QR
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用户在web层构造查询条件detachedCriteria,和可选的 0cq@lT6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 93HVx#
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PaginationSupport的实例ps。 i=aR~
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ps.getItems()得到已分页好的结果集 &/? Ct!_
ps.getIndexes()得到分页索引的数组 l~rj7f;
ps.getTotalCount()得到总结果数 }_]AQN$'G
ps.getStartIndex()当前分页索引 e{5?+6KH
ps.getNextIndex()下一页索引 Or5?Gt
ps.getPreviousIndex()上一页索引 sQa;l]O:NC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 E$)| Kv^
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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 ^)Hf%
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一下代码重构了。 eBrNhE-[G]
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我把原本我的做法也提供出来供大家讨论吧: eWcqf/4?"
[CI&4) #
首先,为了实现分页查询,我封装了一个Page类: w(Z ?j%b
java代码: 32[}@f2q
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/*Created on 2005-4-14*/ b_31 \
package org.flyware.util.page; vFVUdxPOw
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/** !4vb{AH
* @author Joa VGV-t
* N'v3
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*/ )hZ7`"f,ZN
publicclass Page { t )zd'[
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/** imply if the page has previous page */ +.V+@!
privateboolean hasPrePage; 9(N
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/** imply if the page has next page */ $jN.yNm0
privateboolean hasNextPage; /MF
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/** the number of every page */ <b:%o^
privateint everyPage; Hb=#`
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/** the total page number */ VsQ|t/|#
privateint totalPage; ] 3{t}qY$A
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/** the number of current page */ |p6d]#z3
privateint currentPage; rwF$aR>9
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/** the begin index of the records by the current c{=Sy;i@
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query */ Bu{Kjv
privateint beginIndex; }>xwiSF?
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/** The default constructor */ ED&nrd1P
public Page(){ C? zS}ob
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} !#KKJ`uB"
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/** construct the page by everyPage cc[(w
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* @param everyPage ]Y\$U<YjO
* */ .@VZ3"
public Page(int everyPage){ !mNst$-H4
this.everyPage = everyPage; 24jf`1XFW
} W0gS>L_
I=0c\ U}
/** The whole constructor */ \OwF!~&
public Page(boolean hasPrePage, boolean hasNextPage, Unk/uk
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int everyPage, int totalPage, ],]Rv#`
int currentPage, int beginIndex){ fkxkf^g)
this.hasPrePage = hasPrePage; 1q}LO2
this.hasNextPage = hasNextPage; V:n0BlZ,B
this.everyPage = everyPage; a"vzC$Hxd
this.totalPage = totalPage; Lw>B:3e
this.currentPage = currentPage; [6!k:-t+
this.beginIndex = beginIndex; }t)+eSUA
} jx}&%p X
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/** .WF"vUp
* @return n7!T{+ge
* Returns the beginIndex. WPNB!"E98
*/ M)bQvjj
publicint getBeginIndex(){ cgb>Naa<
return beginIndex; h.\I
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} Tv ``\<
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/** c!Hz'W
* @param beginIndex 4Q|>k)H
* The beginIndex to set. <o(;~
*/ t<!m4Yd|#
publicvoid setBeginIndex(int beginIndex){ fd)8lK[KJ"
this.beginIndex = beginIndex; qezWfR`
} Z<vz%7w
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/** ytcLx77`:
* @return <XeDJ8
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* Returns the currentPage. N^;lp<{6?
*/ z9o]);dZ
publicint getCurrentPage(){ >dAl *T
return currentPage; IK -vcG
} K"!rj.Da
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/** @@Q4{o
* @param currentPage zIc6L3w$
* The currentPage to set. DsdM:u*s
*/ EavBUX$O
publicvoid setCurrentPage(int currentPage){ IL@yGuO,
this.currentPage = currentPage; n_QuuUB
} k\OZ'dS
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/** y_WC"
* @return Oc)n,D)0
* Returns the everyPage. :,8y8z$+
*/ g#I`P&
publicint getEveryPage(){ ;j0.#P:a
return everyPage; Q6
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} {\$S585
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/** 4!!|P
* @param everyPage maap X/J
* The everyPage to set. G@s:|oe
*/ c^|8qvS$
publicvoid setEveryPage(int everyPage){ Z!v,;MW
this.everyPage = everyPage; @[^ 3yC#
} eu(Fhs
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/** ~A0AB
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* @return =-dnniKW4
* Returns the hasNextPage. DFr$2Y3H
*/ Jk.x^
publicboolean getHasNextPage(){ 8r(Vz
return hasNextPage; lO@-*m$
} Vz mlKVE
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/** m-{DhJV
* @param hasNextPage Rxy|Ag/I;V
* The hasNextPage to set. kHK<~srB
*/ $
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publicvoid setHasNextPage(boolean hasNextPage){ U`*we43
this.hasNextPage = hasNextPage; ~D5
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} }-[l)<F:
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/** SrA6}kS
* @return as:=QMV
* Returns the hasPrePage. XU'(^Y8Imz
*/ ~vF*&^4Vh
publicboolean getHasPrePage(){ O!Ue0\1Kj0
return hasPrePage; 2Wcu.
} r,eH7&P9{
% 3#g-
/** v=^^Mr"Z^
* @param hasPrePage VmQ^F|
{
* The hasPrePage to set. wo9R:kQ
*/ 3r%v@8)!b
publicvoid setHasPrePage(boolean hasPrePage){ L'y0$
this.hasPrePage = hasPrePage; 6F^/k,(k4
} l"8g9z
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/** QmBHD;Gf
* @return Returns the totalPage. t(}Y /'
* 9ERdjS
*/ 5T/+pC$e=
publicint getTotalPage(){ XzAXcxC6G
return totalPage; 3\2&?VAjR
} >(:3H+
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/** ejg!1*H@n
* @param totalPage J#d,?
* The totalPage to set. .UxkTads
*/ H8HH) ^
publicvoid setTotalPage(int totalPage){ T3b0"o27
this.totalPage = totalPage; }5E H67
} 0yjYjIk"T
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} wgSFL6Ei
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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 \1R*M
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个PageUtil,负责对Page对象进行构造: hj=n;,a9
java代码: covCa )kf
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/*Created on 2005-4-14*/ tli*3YIw
package org.flyware.util.page; |QrVGm@2
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import org.apache.commons.logging.Log; El}~3|a?
import org.apache.commons.logging.LogFactory; ]_ LAy
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/** ; 180ct4
* @author Joa =>*}qen
* _bh$
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*/ >>=zkPy
publicclass PageUtil { 25G~rklk
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privatestaticfinal Log logger = LogFactory.getLog B4OFhtYE
}T%E;m-
(PageUtil.class); 1%@i4
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/** h6Vd<sV\tf
* Use the origin page to create a new page a;i}<n7
* @param page tm;\m!^X{
* @param totalRecords TPJuS)TU9
* @return uxW |&q
*/ 7WV"Wrl]
publicstatic Page createPage(Page page, int %i&am=
MDpx@.A,
totalRecords){ ][f 0ZMa
return createPage(page.getEveryPage(), fN`Prs A
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page.getCurrentPage(), totalRecords); BT:b&"AR[
} _J>Ik2EF
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/** 98}l`J=i
* the basic page utils not including exception ~LH).\V
@&h_+|:-
handler Q{hK+z`D
* @param everyPage &Ai+t2
* @param currentPage $9@Z\0
* @param totalRecords ?:PF;\U
* @return page %AMF6l[
*/ _=w=!U&W
publicstatic Page createPage(int everyPage, int CS^|="Zs
a/d8_(0
currentPage, int totalRecords){ nQw, /Lk
everyPage = getEveryPage(everyPage); ylmVmHmc
currentPage = getCurrentPage(currentPage); * se),CP!s
int beginIndex = getBeginIndex(everyPage, ~@^ pX*%i
OoOwEV2p_
currentPage); 2J(,Xf
int totalPage = getTotalPage(everyPage, m7,"M~\pX
m,J9:S<5;
totalRecords); FOa2VP%
boolean hasNextPage = hasNextPage(currentPage, s4 Uk5<
Si;eBPFH
totalPage); kKQD$g.z6
boolean hasPrePage = hasPrePage(currentPage); `C:J {`
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returnnew Page(hasPrePage, hasNextPage, f+Bv8 g
everyPage, totalPage, N[=R$1\Z
currentPage, o`jV d,aj
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beginIndex); *xKY>E+
} f<DqA/$
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privatestaticint getEveryPage(int everyPage){ 5X`m.lhUc
return everyPage == 0 ? 10 : everyPage; cTJG1'm
} ^O5PcV 3Eg
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MxJ
privatestaticint getCurrentPage(int currentPage){ r-}C !aF]
return currentPage == 0 ? 1 : currentPage; }8'bXG+
} XQ k,xQ
B?XqH_=0L
privatestaticint getBeginIndex(int everyPage, int BfvvJh_
p6{8t}
currentPage){ jivGkIj!8
return(currentPage - 1) * everyPage; O~bzTn
} M-f; ,>
x8rp Z
privatestaticint getTotalPage(int everyPage, int }!vJ+
,|R\ Z,s
totalRecords){ !uHVg(}
int totalPage = 0; /vPcg
sr$JFMTO11
if(totalRecords % everyPage == 0) !_1RQ5]^
totalPage = totalRecords / everyPage; vP&JL~
else BG20R=p
totalPage = totalRecords / everyPage + 1 ; 6c#1Do(W+
SQBe}FlktK
return totalPage; 9r,7>#IF
} oGZ%w4T
lGN{1djT
privatestaticboolean hasPrePage(int currentPage){ [)p>pA2GZj
return currentPage == 1 ? false : true; )6-!,D0 db
} }W"/h)q
.GDNd6[K7
privatestaticboolean hasNextPage(int currentPage, (^Hpe5h&
z/S}z4o/
int totalPage){ bu r0?q
return currentPage == totalPage || totalPage == &qFy$`"
Z:%~Al:
0 ? false : true; <bOi }
} $~.'Tnk)
>BlF<
d`X
n|I5ylt
} [[0u|`T/
$>PV6
||kUi=5
|Xk>a7X
odpjEeQC
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。 |`6*~ciUV
H(j983
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 0W>,RR)
?,x3*'-(
做法如下: w57D qG>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 L(qQ,1VY
r5aOQ
的信息,和一个结果集List: *U^7MU0
java代码: 3,-xk!W$L
r(cd?sL96R
n[`FoY
/*Created on 2005-6-13*/ /q >1X!Z
package com.adt.bo; .qk_m-o
OuF%!~V
import java.util.List; TW}nO|qw
e47N 9&4
import org.flyware.util.page.Page;
UB1/0o
La'XJ|>V
/** 2i_k$-
* @author Joa %Y// }
*/ gCY%@?YyN
publicclass Result { Z |CL:)h
-mK;f$X
private Page page; EG[Rda
i"o
%Gc
private List content; &ywU^hBh
=5m~rJ<{
/** Z]1jg>")
* The default constructor hUGP3ExC*
*/ }&O}t{gS*
public Result(){ 5WvtvSO
super(); /V@9!
} FpM0 %
%gE*x
#
/** u
=%1%p,
* The constructor using fields },LO]N|
* a"&Gs/QKSC
* @param page m3E`kW|
* @param content Wc
qUF"A
*/
+Q+>{HK
public Result(Page page, List content){ wXnluE
this.page = page; <*55d2
this.content = content; -3On^Wj]
} ii:E>O(0B
;XXB^,
/** #?EmC]N7
* @return Returns the content. 48Z0aA~+
*/ CDU$Gi
publicList getContent(){ %qqX-SF0C
return content; ruQ1Cph
} RO+N>Wkt
HJeZm
/** Gm2q`ki
* @return Returns the page. w[X/|O
*/ qmx4hs8sh
public Page getPage(){ s/0S]P]}f
return page; DYFfq
} #XPY\n^k
7dbGUbT
/** ?(d<n
* @param content oi:!YVc
* The content to set. NP^j5|A*"
*/ Oq3]ZUVa
public void setContent(List content){ KJ;;825?
this.content = content; `}Z`aK
} [Y_CRxa\u
>q7/zl
/** mxfmK +'_
* @param page qPG>0
O
* The page to set. A,;V|jv9
*/ M4`.[P4
publicvoid setPage(Page page){ /l&$B
this.page = page; nA?Ks!9T
} EYD24
} z[~ph/^
gJC~$/2
O4.`N?Xq
GLE/ 1
7`_`V&3s
2. 编写业务逻辑接口,并实现它(UserManager, Z& W*@(dX
p.|NZXk%%a
UserManagerImpl) }a?( }{z-
java代码: X&14;lu%p
g<(\# F}/
#l?E2
U4WL
/*Created on 2005-7-15*/ P ")1_!
package com.adt.service; |.EC>D/
&kp`1kv":
import net.sf.hibernate.HibernateException; jC}2>_#m(
QxI^Bx
import org.flyware.util.page.Page; O; #qG/b1
Hru~Y}V
import com.adt.bo.Result; (@&+?A"6`
QRKr2:o{
/** :qe.*\
c
* @author Joa ?hh#@61
*/ z<u*I@;
publicinterface UserManager { Xdtyer%
D(&XmC[\Y
public Result listUser(Page page)throws O=;}VZ<9
_my!YS5n
HibernateException; !}pvrBS
ews{0
} nc/F@HCB
V
krjs0
gHmy?+)
&cHA xker
UsQh+W"?
java代码: UrJrvx
PyQ
P K,
/k O
<o&
/*Created on 2005-7-15*/ }u?DK,R
package com.adt.service.impl; 6O0CF}B*
iwx*mC{|A
import java.util.List; YM.Q?p4g
>%1mx\y^
import net.sf.hibernate.HibernateException; -4!S?rHwd+
GMW,+
import org.flyware.util.page.Page; NPjNkpWm&=
import org.flyware.util.page.PageUtil; }$X/HK
c>.=;'2
import com.adt.bo.Result; `m+o^!SGe
import com.adt.dao.UserDAO; Bb9/nsbE
import com.adt.exception.ObjectNotFoundException; p|9Eue3j2
import com.adt.service.UserManager; %s*F~E
.6HHUy
/** $3)Z>p
* @author Joa @T@lHc
*/ f{+n$Cos
publicclass UserManagerImpl implements UserManager { ~U$ioQy<
wT@{=s,
private UserDAO userDAO; /k^!hI"4c
WinwPn+9
/** ?w5>Z/V
* @param userDAO The userDAO to set. (t_%8Eu
*/ B6J<
publicvoid setUserDAO(UserDAO userDAO){ 26B+qXEt
this.userDAO = userDAO; 94Q?)0W$
} q)Qg'l^f
*wp>a?sG\
/* (non-Javadoc) 8'|_O
* @see com.adt.service.UserManager#listUser ,%<ICusZ
ZZ2vdy38
(org.flyware.util.page.Page) /0z#0gNp
*/ "rU
2g
public Result listUser(Page page)throws #,B+&SK{
V_"UiN"o
HibernateException, ObjectNotFoundException { !Y^3% B%
int totalRecords = userDAO.getUserCount(); Hkzx(yTi
if(totalRecords == 0) '1vm]+oM
throw new ObjectNotFoundException 88g|(k/
0f9*=c
("userNotExist"); `/RcE.5n\@
page = PageUtil.createPage(page, totalRecords); HIsB)W&%@
List users = userDAO.getUserByPage(page); dh K<5E
returnnew Result(page, users); d<_#Q7]I4
} vugGMP;D(
6x iCTs0@
} ;GV~MH-F
w{89@ XRC
~ya@ YP]';
2#)z%K6T
ioJ|-@!#o
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #,CK;h9jy!
V)jF]u~g
询,接下来编写UserDAO的代码: E'+?7ZGWj
3. UserDAO 和 UserDAOImpl: yt[*4gF4
java代码: Xv2Q8-}w
jUGk=/*]e
+nz0ZQ9 a
/*Created on 2005-7-15*/ X|4_}b> x
package com.adt.dao; vM?jm!nd
"1z#6vw5a
import java.util.List; [ XBVES8
Lhmb=
@
import org.flyware.util.page.Page; pE381Cw
?.Lq`~T`
import net.sf.hibernate.HibernateException; GZzBATx
sh)[|?7z
/** 7p_B?r
* @author Joa ^,{ r[}
*/ 4_W*LG~2s
publicinterface UserDAO extends BaseDAO { g]Z@_
6H^=\
publicList getUserByName(String name)throws OJT%?P%@{
}NY! z^
HibernateException; ycj\5+g
Rj!9pwvT
publicint getUserCount()throws HibernateException; +j(7.6ia
w)Z-, J
publicList getUserByPage(Page page)throws kK_9I (7c
pSdtAv
HibernateException; l]~mB~
71G\b|5
} fb?YDM
'cPE7uNT
!EOYqD
@&f~#Xe
ukc<yc].+?
java代码: Jxsch\
Nin7AOO
Kr%w"$<
/*Created on 2005-7-15*/ J936o3F_
package com.adt.dao.impl; Aa}Nr5{O|
k]=lo'bF4
import java.util.List; X}ft7;Jpy
(w1$m8`=
import org.flyware.util.page.Page; s(pNg?R
C`["4
import net.sf.hibernate.HibernateException; Qb#iT}!p%
import net.sf.hibernate.Query; vVf%wei^#
TpRI+*\
import com.adt.dao.UserDAO; dhV6r
~S~4pK
/** h
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* @author Joa S!8q>d,%L
*/ UTVqoCHA
public class UserDAOImpl extends BaseDAOHibernateImpl UO4z~
W%@0Y m`7
implements UserDAO { )St`}qu;
"@UyUL
/* (non-Javadoc) k{J\)z
* @see com.adt.dao.UserDAO#getUserByName pcNpr`
JQDS3v=1$
(java.lang.String) z-JYzxL9
*/ NeR1}W
publicList getUserByName(String name)throws "L+NN|
J[al4e^
HibernateException { ,qwVDYJ
String querySentence = "FROM user in class md;jj^8zj
Bk@&k}0
com.adt.po.User WHERE user.name=:name"; -=GmI1:=$4
Query query = getSession().createQuery u9j1>QU
h3j`X'
(querySentence); YQ`88z
query.setParameter("name", name); r<!/!}fE,
return query.list(); ~F[JupU
} hVW1l&s
t#2szr+
/* (non-Javadoc) >0S(se$
* @see com.adt.dao.UserDAO#getUserCount() Le2rc*T
*/ ?*:BgaR_
publicint getUserCount()throws HibernateException { +6s6QeNS8
int count = 0; F7\nG}#s
String querySentence = "SELECT count(*) FROM FW:V<{f
]SUW"5L-
user in class com.adt.po.User"; AZva
Query query = getSession().createQuery [/U5M>#n
OjsMT]
(querySentence); y*T@_on5
count = ((Integer)query.iterate().next o'=i$Eb
C ett*jm_
()).intValue(); )j}v3@EM5
return count; -IS$1
}
!SThK8j$7
$|VD+[jSV
/* (non-Javadoc) $k^&
X
`
* @see com.adt.dao.UserDAO#getUserByPage =\gK<Xh
^C~t)U
(org.flyware.util.page.Page) ;aDYw [
*/ Q|7;Zsd:
publicList getUserByPage(Page page)throws @=qWwt4~
K~A@>~vFb
HibernateException { %<\tN^rP
String querySentence = "FROM user in class Id{Ix(O
~;@\9oPpz%
com.adt.po.User"; rTzXRMv@o
Query query = getSession().createQuery QeQxz1
z'}z4^35,
(querySentence); @+hO,WXN
query.setFirstResult(page.getBeginIndex()) : 2A\X' @
.setMaxResults(page.getEveryPage()); ~vKDB$2
return query.list(); m6o o-muAr
} ;-VXp80J
xG|lmYt76
} gW^0A)5
y<m}dW6[\
{cmV{ 4Yx
\Wb3JQ)
`gdk,L]
至此,一个完整的分页程序完成。前台的只需要调用 v,c;dlg_
Vkl]&mYRz
userManager.listUser(page)即可得到一个Page对象和结果集对象 n!L}4Nmp
/gP"X1.
的综合体,而传入的参数page对象则可以由前台传入,如果用 UVD*GsBk
1 Ay.^f
webwork,甚至可以直接在配置文件中指定。 KNSMx<GP
F@1Eg
下面给出一个webwork调用示例: p*|Ct
java代码: M-A{{q
Ur(< ]
%8lWJwb7u
/*Created on 2005-6-17*/ *a' I
package com.adt.action.user; G!U
`8R
BrsBB"<o,
import java.util.List; oT9qd@uQ0:
m'U>=<!D
import org.apache.commons.logging.Log; )|
F O>
import org.apache.commons.logging.LogFactory; a.up&g_$
import org.flyware.util.page.Page; &,'CHBM
y|(?>\jBl
import com.adt.bo.Result; |fPR7-
import com.adt.service.UserService; )OZ
import com.opensymphony.xwork.Action; w%~Mg3|
-NUA
/** in2m/q?
* @author Joa D YTC2
*/ bl[2VM7P
publicclass ListUser implementsAction{ ^F87gow%`B
90">l^HX=
privatestaticfinal Log logger = LogFactory.getLog \'+P5,
r[3 2'E
(ListUser.class); Q$x
3uH\@
Nx<fj=VJ
private UserService userService; 43Ua@KNi
PDpDkcy|QM
private Page page; k.wm{d]J
{=, +;/0
privateList users; ^@;P -0Sy
P=.T|l1
/* ^TAf+C^Ry
* (non-Javadoc) 3e1^r_YI
* B dxV [SF
* @see com.opensymphony.xwork.Action#execute() DS=Dg@y
*/ {$'oKJy*
publicString execute()throwsException{ dyt.(2
Result result = userService.listUser(page); )pw53,7>aN
page = result.getPage(); uwu`ms7z 2
users = result.getContent(); P.kf|,8L
return SUCCESS; `FAZAC\
} ~/;shs<9EM
`Lr|KuFN
/** @O
HsM?nW
* @return Returns the page. }M &hcw<
*/ 1
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public Page getPage(){ Y"E*#1/
return page; ,ZvlKN
} 2 P9{?Y
vn ^*
/** 6 IKi*}
* @return Returns the users. I~25}(IDZ"
*/ ]_2<uK}fg
publicList getUsers(){ r-5xo.J'
return users; +g%Ah
} #fxdZm,
i"#zb&~nF
/** k];fQ7}m<0
* @param page (ljoD[kZ
* The page to set. (w?W=guHu
*/ zI'c 'X1,
publicvoid setPage(Page page){ D"X`qF6U7
this.page = page; [[KIuW~ot
} |L~RC
=8EGB\P
/** .gA4gI1kH
* @param users 7
'{wl,u
* The users to set. cTLW}4m%g
*/ La\|Bwx
publicvoid setUsers(List users){ td|O #R
this.users = users; XO}v8nWV
} w s7LDY&(
~4M?[E&
/** d*Kg_He-
* @param userService =p&uQ6.i+
* The userService to set. IvM>z03
*/ xcQ:&q
publicvoid setUserService(UserService userService){ n(jrK9]
this.userService = userService; s^GE>rf
} Pi=B\=gs
} 3|0OW
Jk
}N@+bNh~
8C<%Y7)/
<Y ^)/ s
@!%HEs!# #
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, h
F *c
A'T: \Wl
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 en29<#8TO
+EM^
么只需要: |. LE`
java代码: ?xtP\~
xU'% 6/G
V)cL=4G
<?xml version="1.0"?> Mgg m~|9)
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^qV6khg
]/od p/jm
1.0//EN" "http://www.opensymphony.com/xwork/xwork- MO_;8v~0
I|)U>bV
1.0.dtd"> AHn
Yfxv_
z:JJ>mxV
<xwork> SHN'$f0Mb
YfVZ59l4y6
<package name="user" extends="webwork- bw OG|\
I5w>*F
interceptors"> R<e ~Cb-
pSS8 %r%S'
<!-- The default interceptor stack name w~WW2w
(r"2XXR
--> r*t\F&D
<default-interceptor-ref fk(h*L|sI
YFs!,fw'
name="myDefaultWebStack"/> {S5j;
%#@5(_'
<action name="listUser" h3P ^W(=&
C7_#D O6"
class="com.adt.action.user.ListUser"> 8o!LgT5
<param "%K[kA6
AR7]~+X
name="page.everyPage">10</param> *hkNJ
<result zl@hg<n
"[\),7&03
name="success">/user/user_list.jsp</result> I=K|1
</action>
U].3vju`c
oPR?Ar
</package> SJ8|~,vL
Oi\,clR^[o
</xwork> p=]z`t
swG!O}29OX
2q%vd=T
;<nQl,2N
Y]H,rO
H]VoXJ\*
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 0R}F(tjw
nBGcf(BE.$
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。 R9O1#s^
Un\
T}
c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Q ;$NDYV1
obSLy
Ed
GJn ~x
?TY/'-M5
tz/NR/[
我写的一个用于分页的类,用了泛型了,hoho /%i: (Ny
#iP5@:!Wm~
java代码: ')1p
yo_;j@BGR
4,?ZNyl
package com.intokr.util; 3nX={72<b
}TwSSF|}3
import java.util.List; vs(x;zpJ
Hjc *WTu
/** cUc:^wvLS
* 用于分页的类<br> GbJVw\5Z*
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "UTAh6[3oD
* */A ~lR|
* @version 0.01 ZoroK.N4A%
* @author cheng ,nz3S5~
*/ 6:qh%ZR
public class Paginator<E> { U$ 22 r b
privateint count = 0; // 总记录数 tqicyNL
privateint p = 1; // 页编号 &,C;_3
privateint num = 20; // 每页的记录数 _4~q&?}V
privateList<E> results = null; // 结果 C
vWt
0p1~!X=I
/** D4\
*
,w
* 结果总数 Q(h/C!rKe
*/ M 3c
publicint getCount(){ yf2$HF
return count; p+; La
} }<g-0&GLm
#wfb-`,5&9
publicvoid setCount(int count){ {=<m^
5b9
this.count = count; "wj-Qgz
} )9z3T>QW
.|<+-Rsj
/** _X]S`e1F
* 本结果所在的页码,从1开始 |ZJ<N\\h-
* (v1~p3H
* @return Returns the pageNo. oO][X
*/ 4-Cca
publicint getP(){ `rZS\A
return p; 1$1P9x@H
} CyD)=e{
5nv1%48Ri
/** fm&pxQjg
* if(p<=0) p=1 6;#Rd|
* ]c\d][R N
* @param p %
n~
'UA
*/ )@a_|q@V
publicvoid setP(int p){ x0$# 8
if(p <= 0) (?lKedA>2
p = 1; zb& 3{,
this.p = p; jxTYW)E
} {q|Om?@
J:oAzBFpA
/** EN{o3@ O'
* 每页记录数量 lq}g*ih
*/ M*7:-Tb]C
publicint getNum(){ tLo_lLn*~%
return num; q-TDg0
} ,BE4z2a
%rq/jC
/** %3mh'Z -[f
* if(num<1) num=1 d{*e0
*/ T7~Vk2o%(
publicvoid setNum(int num){ DBk]2W|i
if(num < 1) POt8G
num = 1; vbSycZ2M7
this.num = num; o2W^!#]=
} eGj[%pk
=uD^#AX
/** ?<6yKxn
* 获得总页数 0t(js_
*/ $&jte_hv
publicint getPageNum(){ =9L1Z \f
return(count - 1) / num + 1; go
B'C
} u @#fOu
p-JGDjR0G
/** 2tI ,`pSU
* 获得本页的开始编号,为 (p-1)*num+1 @tg4rl
*/ <T+{)FV
publicint getStart(){
B`wrr8"Rz
return(p - 1) * num + 1; 0=Mu|G|Z
} _FtsO<p)"
>m#bj^F\
/** 9#b/D&pX5
* @return Returns the results. ^b^}6L'Z
*/ }b=Cv?Zg$m
publicList<E> getResults(){ _q=ua;I&
return results; p}K.-S`MQ
} %hCd*[Z}j
u?I 2|}#
public void setResults(List<E> results){ l" +q&3Zx
this.results = results; .T\_4C
} @23~)uiZa
R/Z
zmb{
public String toString(){ d34BJ<
StringBuilder buff = new StringBuilder 8ib%CYR
MkX=34oc^
(); }0~X)Vgm(
buff.append("{"); 2VaKt4+`
buff.append("count:").append(count); qA5 Ug
buff.append(",p:").append(p); 3H,?ZFFGz
buff.append(",nump:").append(num); J/B`c(
buff.append(",results:").append jchq\q)_z
{pk]p~
(results); R(p3*t&n
buff.append("}"); W(\^6S)
return buff.toString(); O#?@'1
} "? ON0u9
5%RiM|+
} z4{:X Da
yoG*c%3V?
4}F~h