Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 s0k`p<q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :F{:Z*Fi0
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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 q(.:9A*0
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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 !,Va(E|=
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。 -/ g B|J
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分页支持类: &'}RrW-s
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java代码: znaUB v_
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package com.javaeye.common.util; b{]z
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import java.util.List; Zy(W^~NT
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publicclass PaginationSupport { ]2\VweV
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publicfinalstaticint PAGESIZE = 30; )Cc q4i
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privateint pageSize = PAGESIZE; w &(|e <
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privateList items; O^^C;U@U<1
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privateint totalCount; -2 A(5B9Fq
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privateint[] indexes = newint[0]; %Cv D-![0
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privateint startIndex = 0; ` M3w]qJ<}
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public PaginationSupport(List items, int (KF=On;=Y
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totalCount){ .b6VQCS~9
setPageSize(PAGESIZE); Ksy -e{n
setTotalCount(totalCount); j&Wl0
setItems(items); >w^YO25q
setStartIndex(0); ~?FpU
} Ju
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public PaginationSupport(List items, int [3--(#R\}?
7TDy.]
totalCount, int startIndex){ 86mp=6@
setPageSize(PAGESIZE); |]ZYa.+:
setTotalCount(totalCount); =MLcm^b
setItems(items); OC<5E121>Y
setStartIndex(startIndex); .P MZX%*v
} -QmO1U
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public PaginationSupport(List items, int FWHNj.r
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totalCount, int pageSize, int startIndex){ ~;&m*2
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setPageSize(pageSize); @Q/-s9b
setTotalCount(totalCount); 2g>SHS@1>
setItems(items); fIwV\,s
setStartIndex(startIndex); jr!?v<NoX
} _cJ2\`M
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publicList getItems(){ LM-J !44
return items; hijgF@
}
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publicvoid setItems(List items){ '_/Bp4i
this.items = items; fmiz,$O4?
} T<w5vqFDu
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publicint getPageSize(){ uec!RKE
return pageSize; uJ5Eka
} m:WyuU<
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publicvoid setPageSize(int pageSize){ D*F4it.
this.pageSize = pageSize; D6Goa(!9d
} eQD)$d_5
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publicint getTotalCount(){ -!N&OZ+R
return totalCount; 0Emr<n
} q"<ac qK
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publicvoid setTotalCount(int totalCount){ vL\&6n~M>
if(totalCount > 0){ <B6&I$Wc+
this.totalCount = totalCount; d)R:9M}v
int count = totalCount / WeQk<y
( 2n>A D_
pageSize; V8HnUuz
if(totalCount % pageSize > 0) pk3<|
count++; 6u`)QUmItg
indexes = newint[count]; C~N/A73gF
for(int i = 0; i < count; i++){ %y|)=cm[
indexes = pageSize * L_+k12lm
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i; R@6zGZ1
} jlBanGs?
}else{ I]Dl /
this.totalCount = 0; F;l$.9? .s
} OQ>x5?um
} mysetv&5
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publicint[] getIndexes(){ CO2C{~Q5
return indexes; ]zQo>W$
} ;r>snJ=M
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publicvoid setIndexes(int[] indexes){ bVL9vNK
this.indexes = indexes; 3plzHz ,x
} 'C
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publicint getStartIndex(){ _&j}<K$-(
return startIndex; _`_%Y(Xat
} nM-h&na{s
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publicvoid setStartIndex(int startIndex){ bD[!/'4eJ
if(totalCount <= 0) M5*{
this.startIndex = 0; -R%<.]fJ
elseif(startIndex >= totalCount) DV\`Wv
this.startIndex = indexes @1 U&UH
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[indexes.length - 1]; H*Kj3NgY
elseif(startIndex < 0) e=Z,
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this.startIndex = 0; Sz^5b!
else{ ;zIP,PMM
this.startIndex = indexes spGB)k,^
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[startIndex / pageSize]; ;IVDr:
} 8ZKo_I\
} h|h>u
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publicint getNextIndex(){ |pmZ.r
int nextIndex = getStartIndex() + LwK+:4$
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pageSize; q&Gz ]
if(nextIndex >= totalCount) eOXHQjuj
return getStartIndex(); /qx0TDB
else 8 XICF
return nextIndex; $`wMX{
} H~+ l7OhV
awOd_![c'
publicint getPreviousIndex(){ mFSw@CC
int previousIndex = getStartIndex() - H]$)Eg%6
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pageSize; 't_[dSO
if(previousIndex < 0) t: IN,Kl4
return0; FRS>KO=3
else {2+L@
return previousIndex; ;[W"mlM
} <IC~GqXv
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} cFJ-Mkll
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抽象业务类 aAA9$
java代码: 3nu^l'WQ
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/** sz)oZPu|
* Created on 2005-7-12 RgGyoZ
*/ _x?uU
package com.javaeye.common.business; ObE,$_ k
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import java.io.Serializable; ~,BIf+\XF
import java.util.List; g*F '[Z."
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import org.hibernate.Criteria; :LQ5u[g$\
import org.hibernate.HibernateException; K,e w >U
import org.hibernate.Session; x#Q>J"g
import org.hibernate.criterion.DetachedCriteria; )DeA}e?F
import org.hibernate.criterion.Projections; >A<bBK#
import v k?skN@
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org.springframework.orm.hibernate3.HibernateCallback; :pF_GkG
import a?6ab+7#
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org.springframework.orm.hibernate3.support.HibernateDaoS Qed.4R:o
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upport; gt ";2,;X
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import com.javaeye.common.util.PaginationSupport; m@Qt.4m%g
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public abstract class AbstractManager extends r.T<j.\
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HibernateDaoSupport { :Pg}Zz <
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privateboolean cacheQueries = false; q~59F@
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privateString queryCacheRegion; )6w}<W*1E
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publicvoid setCacheQueries(boolean T`9u!#mT=
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cacheQueries){ :Mcu
this.cacheQueries = cacheQueries; gi-Yqco
} RiTa \
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publicvoid setQueryCacheRegion(String Ik[s
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queryCacheRegion){ sU!6 hk
this.queryCacheRegion = d~?X/sJ t
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queryCacheRegion; +E; 2d-x*p
} sU"}-de
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publicvoid save(finalObject entity){ Sje wuIi1
getHibernateTemplate().save(entity); JIFU;*PR1
} #CnHf
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publicvoid persist(finalObject entity){ %\kOLE2`
getHibernateTemplate().save(entity); q\q=PB6r
} ErT{(t7
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publicvoid update(finalObject entity){ 7]BW[~77
getHibernateTemplate().update(entity); `- \/$M9s=
} 3GmeD/6
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publicvoid delete(finalObject entity){ qA:#iJ8w
getHibernateTemplate().delete(entity); )$&dg2[
} if)Y9:{r^
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publicObject load(finalClass entity, #k$)i[aI-
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finalSerializable id){ ~+H"
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return getHibernateTemplate().load -wv6s#"u
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(entity, id); VN'Wq7>6
} W>=o*{(YO
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publicObject get(finalClass entity, 4_D@ST%
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finalSerializable id){ 5I,gBT|B
return getHibernateTemplate().get jr /lk
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(entity, id); :qvI%1cP=
} kwud?2E
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publicList findAll(finalClass entity){ e2+BWKaU
return getHibernateTemplate().find("from =X!IHd0
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" + entity.getName()); om3`[r[{
} yfDAk46->6
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publicList findByNamedQuery(finalString Z/6qG0feJ
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namedQuery){ Z Dhx5SL&
return getHibernateTemplate !~ZP{IXyo
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().findByNamedQuery(namedQuery); axk"^gps
} s 1ge0~p3
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publicList findByNamedQuery(finalString query, }6-ZE9H-v
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finalObject parameter){ \#rO!z
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return getHibernateTemplate ya
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().findByNamedQuery(query, parameter); o]LRzI
} P(SZ68
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publicList findByNamedQuery(finalString query, 7$k8%lI;>
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finalObject[] parameters){ a{!r`>I\f
return getHibernateTemplate 3SBZ>
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().findByNamedQuery(query, parameters); ;XC@=RpX
} U{ ;l0 2S
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publicList find(finalString query){ AY SSa 1}
return getHibernateTemplate().find [Qdq}FYr
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(query);
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} %@R~DBS
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publicList find(finalString query, finalObject 4.K'\S
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parameter){ %gcc
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return getHibernateTemplate().find 1#
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(query, parameter); ?`zgq>R}w[
} quo^fqS&a
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public PaginationSupport findPageByCriteria =/+#PVO
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(final DetachedCriteria detachedCriteria){ eX2<}'W<
return findPageByCriteria d'l$$%zJ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); `!G7k
} (D{Ys'{q
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public PaginationSupport findPageByCriteria 0+b0<
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(final DetachedCriteria detachedCriteria, finalint NNa1EXZ[
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startIndex){ z}.D"
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return findPageByCriteria \NX Q
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(detachedCriteria, PaginationSupport.PAGESIZE, /.=r>a}l
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startIndex); DI&MC9j(
} YCw('i(|
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public PaginationSupport findPageByCriteria q2_`v5t
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(final DetachedCriteria detachedCriteria, finalint LQ-6vrbs
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pageSize, 3D)b*fPc
finalint startIndex){ ?z"KnR+?Q
return(PaginationSupport) `<j_[(5yb
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getHibernateTemplate().execute(new HibernateCallback(){ *(*+`qZL{(
publicObject doInHibernate gvnj&h.GV
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(Session session)throws HibernateException {
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Criteria criteria = j[P8
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detachedCriteria.getExecutableCriteria(session); kd;'}x=5yP
int totalCount = !%mi&ak(Rn
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((Integer) criteria.setProjection(Projections.rowCount Q-zdJt
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()).uniqueResult()).intValue(); Yb=6C3l@
criteria.setProjection wk02[
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(null); [[qwaI
List items = CW:gEm+
67J*&5? |
criteria.setFirstResult(startIndex).setMaxResults w{'2q^>6*
2z983^
(pageSize).list(); 4YJ=q% G
PaginationSupport ps = jNy?[
)
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new PaginationSupport(items, totalCount, pageSize, Q[s2}Z!N;
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startIndex); |5xz l
return ps; )o8g=7Jm
} Q-R}qy5y
}, true); V_;9TC
} `)[dVfxA
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public List findAllByCriteria(final M^ 5e~y
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate U1Yo7nVf
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().execute(new HibernateCallback(){ 'XTs
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publicObject doInHibernate h#{T}[
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(Session session)throws HibernateException { ypA: P
Criteria criteria = EDN(eh(_
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detachedCriteria.getExecutableCriteria(session); nC~fvyd<P
return criteria.list(); :l~E E!
} ~|R[O^9B
}, true); >I-g[*
} >38
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public int getCountByCriteria(final a9[< ^
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DetachedCriteria detachedCriteria){ Bn-J_-%M
Integer count = (Integer) +a]j[#
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getHibernateTemplate().execute(new HibernateCallback(){ aRKv+{K
publicObject doInHibernate k
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(Session session)throws HibernateException { 6_U|(f
Criteria criteria = n{=7 yK
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detachedCriteria.getExecutableCriteria(session); n4>cERfa
return h]P/KVqR.
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criteria.setProjection(Projections.rowCount WW3
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()).uniqueResult(); ;\s~%~\
} _:5=|2-E
}, true); 6To:T[ z#
return count.intValue(); -gSj>b7T
} q5?L1
} 966<I56+
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用户在web层构造查询条件detachedCriteria,和可选的 "!a`ygqpT
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >i`8R
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PaginationSupport的实例ps。 !u%9;>T7
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ps.getItems()得到已分页好的结果集 6oA~J]<
ps.getIndexes()得到分页索引的数组 1C'P)f28
ps.getTotalCount()得到总结果数 bx7\QU+
ps.getStartIndex()当前分页索引 F(E<,l2[
ps.getNextIndex()下一页索引 V{FE [v_
ps.getPreviousIndex()上一页索引 ?C~X@sq
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 JE9>8+
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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 t]r7cA
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一下代码重构了。 H1C%o0CPY
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我把原本我的做法也提供出来供大家讨论吧: \KNdZC?V2
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首先,为了实现分页查询,我封装了一个Page类: rV~T>x
java代码: `11#J;[@G
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/*Created on 2005-4-14*/ C>.]Bvg
package org.flyware.util.page; >&$ $(Bp
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/** <{$ev&bQ
* @author Joa KU1+<OCh
* b}ySZlmy
*/ 9X
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publicclass Page { a/`c ef
j~+[uzW98
/** imply if the page has previous page */ ?R|fS*e2EB
privateboolean hasPrePage; ) 1lJ<g#
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/** imply if the page has next page */ s5c! ^,L8
privateboolean hasNextPage; N,WI{*
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/** the number of every page */ DZHrR:q?e
privateint everyPage; t`
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/** the total page number */ c*y$bf<
privateint totalPage; LVPt*S= /
ke3HK9P;
/** the number of current page */ - XE79 fQ
privateint currentPage; q`/amI0
1VhoJGH;C
/** the begin index of the records by the current IUh5r(d 68
5en
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query */ L eG7x7n
privateint beginIndex; .\z|Fr
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/** The default constructor */ 8CHb~m@^$
public Page(){ .nj?;).
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} /E`l:&89)
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/** construct the page by everyPage {ED(O-W
* @param everyPage 5]4<!m
* */ s`8M%ZLu
public Page(int everyPage){ OYqYI!N/
this.everyPage = everyPage; "C$!mdr7
} TEaD-mY3
jjS{q,bo
/** The whole constructor */ f_i"/xC-/
public Page(boolean hasPrePage, boolean hasNextPage, `-72>F ;T
4
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int everyPage, int totalPage, -V;0_Nx7p
int currentPage, int beginIndex){ p|bc=`TD
this.hasPrePage = hasPrePage; ,<uiitOo
this.hasNextPage = hasNextPage; l5\B2 +}7
this.everyPage = everyPage; bqg]DO$*
this.totalPage = totalPage; /%J&/2Wz
this.currentPage = currentPage; <
"L){$
this.beginIndex = beginIndex; ?)Czl4J
} ]YisZE4s
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/** 9A/Kn]s(jj
* @return 8!o{W=m^4
* Returns the beginIndex. +E q~X=x
*/ / K_e;(Y_
publicint getBeginIndex(){ lRF_ k
return beginIndex; 48 c
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} H y.3ccZ0
y (c|5CQ
/** $L<_uqSk
* @param beginIndex I{?E /Sc
* The beginIndex to set. 7"a`-]Ap
*/ APHtJoS
publicvoid setBeginIndex(int beginIndex){ :|n>H+Y
this.beginIndex = beginIndex; X%4uShM
} `5k6s,
o@<6TlZM
/** c:h.J4mv
* @return )}k?r5g
* Returns the currentPage. c{m
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*/ gCk y(4
publicint getCurrentPage(){ =E{{/%u{{S
return currentPage; 9%3 r-U=
} F$6])F
dPH!
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/** u/!mN2{Rd
* @param currentPage !\&7oAs=I
* The currentPage to set. fcE/
*/ .UT,lqEkv
publicvoid setCurrentPage(int currentPage){ {0A[v}X ~
this.currentPage = currentPage; hVT=j ?~
} DSDl[;3O{s
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/** A/$KA'jX
* @return A1k&`
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* Returns the everyPage. PNxVW
*/ [/+dHW|
publicint getEveryPage(){ #U!(I#^3
return everyPage; Kbz7
} @ V7ooo!
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/** }GoOE=rhY
* @param everyPage P[#WHbn
* The everyPage to set. qOcG|UgF
*/ aV?}+Y{#
publicvoid setEveryPage(int everyPage){ A5.'h<
this.everyPage = everyPage; (.quX@w"m
} ,rH)}C<Q+
&-8-xw#.
/** ~P]HG;$?n
* @return ArmL,
* Returns the hasNextPage. \[IdR^<YM
*/ +%Bf
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publicboolean getHasNextPage(){ WB=<W#?w7%
return hasNextPage; ?G>5 D`V
} w371.84
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/** 4ye`;hXy
* @param hasNextPage Y&05
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* The hasNextPage to set. ](9{}DHV
*/ G7/?hky 0.
publicvoid setHasNextPage(boolean hasNextPage){ qh)!| B
this.hasNextPage = hasNextPage; -9H!j4]T?
} DX%8.@
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/** q*RaX
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* @return ltr;pc*)
* Returns the hasPrePage. F"m}mf
*/ *(\;}JF-
publicboolean getHasPrePage(){ Gh gvRR$
return hasPrePage; St7D.|
} 1)/T.q<D"
ktw!T{
/** tZNad
* @param hasPrePage #o r7T^
* The hasPrePage to set. f<> YYeY
*/ Xg!|F[i
publicvoid setHasPrePage(boolean hasPrePage){ $vw}p.
this.hasPrePage = hasPrePage; V&,<,iNN
} /_k hFw
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/** %B {D
* @return Returns the totalPage. L
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* e\
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*/ Cj4b]*Q,
publicint getTotalPage(){ YAC zznN
return totalPage; )(ZPSg$/F
} zy/tQGTr@
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/** wh7a|
* @param totalPage Y3MR:{}
* The totalPage to set. k,NU,^ &
*/ &W!d}, ;
publicvoid setTotalPage(int totalPage){ a5U2[Ko80
this.totalPage = totalPage; ^d5./M8Bd
} 7].IT(
3 ?|; on
} <0Egkz3s
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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 E'BH7JV
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个PageUtil,负责对Page对象进行构造: FUqhSW
java代码: <C.$Db&9
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/*Created on 2005-4-14*/ ?9r,Y;,H
package org.flyware.util.page; G}dOx}kT
#PLB$$
import org.apache.commons.logging.Log; a4a[pX,5
import org.apache.commons.logging.LogFactory; a@=36gx)
: {N3o:
/** DHumBnQ
* @author Joa !,JT91
* /DG`Hg
*/ U9p.Dh~)vG
publicclass PageUtil { KGE-RK
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privatestaticfinal Log logger = LogFactory.getLog mKFHT
7E75s)KH
(PageUtil.class); !qGx(D{\
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/** hIO4%RQj_
* Use the origin page to create a new page vzrD"
* @param page q(ET)xCeD
* @param totalRecords pffw5Tc
* @return ZLio8
*/ MoR-8vnJ
publicstatic Page createPage(Page page, int b} U&bFl
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totalRecords){ GwpBDMk
return createPage(page.getEveryPage(), g d}TTe
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page.getCurrentPage(), totalRecords); Hv7D+j8M
} }Keon.N?
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/** ZR q}g:
* the basic page utils not including exception e}O -I
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handler UE`4$^qs
* @param everyPage -^xKG'uth
* @param currentPage b;;Kxi:7$}
* @param totalRecords &{4Mo,x
* @return page D%Jc?6/I#3
*/ 1>@|
publicstatic Page createPage(int everyPage, int 4k2c mM$
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currentPage, int totalRecords){ "O1*uwm
everyPage = getEveryPage(everyPage); 6p]R)K>wS
currentPage = getCurrentPage(currentPage); 79B`w
#
int beginIndex = getBeginIndex(everyPage, |`;1p@w"
^sn>p}Tg
currentPage); "`gZy)E
int totalPage = getTotalPage(everyPage, *0@;
kD=
$No>-^)
totalRecords); |e;z"-3
boolean hasNextPage = hasNextPage(currentPage, >iWf7-:
BaTOh'52
totalPage); ^]!1 'xg
boolean hasPrePage = hasPrePage(currentPage); Yl~?MOk
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returnnew Page(hasPrePage, hasNextPage, ?gMrcc/{
everyPage, totalPage, R qjDMN:
currentPage, pW^ ?g|_}
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beginIndex); I4X+'fW,
} #\S$$gP
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privatestaticint getEveryPage(int everyPage){ 70*iJ^|
return everyPage == 0 ? 10 : everyPage; U
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} nV xMo_
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privatestaticint getCurrentPage(int currentPage){ s!fY^3
return currentPage == 0 ? 1 : currentPage; S9#N%{8P
} [W;dguh
Csm!\I
privatestaticint getBeginIndex(int everyPage, int F`V[G(f+r
wp GnS
currentPage){ Rf0\CEc
return(currentPage - 1) * everyPage; JEF7hJz~
} YM*6W?
'2J6%Gg
privatestaticint getTotalPage(int everyPage, int QV7c9)<]'}
o@` E.4
totalRecords){ _@;3$eB
int totalPage = 0; XoiYtx53
/F}\V
^
if(totalRecords % everyPage == 0) ?CZD^>6
totalPage = totalRecords / everyPage;
:ItW|
else 2bxMIr
totalPage = totalRecords / everyPage + 1 ; H;Qn?^
q]%bd[zkz
return totalPage; Fsj&/:
q
} vA-p}]%
.%b_3s".
privatestaticboolean hasPrePage(int currentPage){ ^JVP2L>o*
return currentPage == 1 ? false : true; Vd>.fb\U2
} s@[t5R
U7%pOpO!
privatestaticboolean hasNextPage(int currentPage, 4S EC4yO
.EZ{d
int totalPage){ D#[ :NXahn
return currentPage == totalPage || totalPage == (E(:F[.S
j/mp.'P1k
0 ? false : true; +Q]'kJ<s
} ugPI1'f
tskODM0Zf
&b")`p&K
} @,`=~_J
n}'.6
]hVXFHrR
LA %al @
gOmyFHv.
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 I>o;
%}
|(v=1#i
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 v4~Xv5|w^F
_W@Fk)E6N
做法如下: =/!S
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 aDv/kFfn
-mw\?\2{
的信息,和一个结果集List: q&6=oss!
java代码: ?,DbV|3_\
oYErG],
Xq!tXJ)
/*Created on 2005-6-13*/ Cwf$`?|W
package com.adt.bo; Rj;e82%%N
"UnSZ[;t
import java.util.List; .ehvhMuG|
<FT\u{9$
import org.flyware.util.page.Page; #$C]0]|
q=i<vcw
/** LK/V]YG
* @author Joa n$Fm~iPo,
*/ H{zuIN/.1
publicclass Result { W2Z]?l;vQQ
0BE^qe
private Page page; ByvqwJY
Y[?Wt/O;
private List content; arL&^]JnZ,
G6VHl:e7z
/** (w
B[ ]O$@
* The default constructor 0)a?W,+O
*/ !Y(qpC:$
public Result(){ &'\+Z
super(); gt (nZ
} A8(PI)Ic.
qk1D#1vl
/** #h|< >
* The constructor using fields \9zC?Cw
* yP]W\W'
* @param page C,u.!g;lm
* @param content !iOu07<n&D
*/ +@7R,8
public Result(Page page, List content){ /2cOZ1G;
this.page = page; ) <~7<.0
this.content = content; ?7a[|-
} ovFfTP<3V
s>I}-=.(Q
/** =ab}.dWC
* @return Returns the content. b"bj|qF~E
*/ k]5L\]>y
publicList getContent(){ rdg1<Z
return content; -~ Q3T9+
} t}l<#X5
uB5o
Ghu-
/** t[,\TM^h}0
* @return Returns the page. IxR:a(
*/ LnX^*;P5t
public Page getPage(){ -;z\BW5y
return page; dUSuhT
} 5L#M7E
x#j_}L!V;
/** C ( ;7*]
* @param content
b6BIDuRb
* The content to set. YO+d+5
*/ q[K)bg{HB
public void setContent(List content){ m:CpDxzbf
this.content = content; <{kj}nxz
} J1t?Qj;f3
*n5g";k|
/** iJeT+}
* @param page }clNXtN
* The page to set. 5]+eLKXB
*/ &>{L"{
publicvoid setPage(Page page){ | 'G$}]H
this.page = page; v}@6"\
} q1Mk_(4oJ
} i%w'Cs0y
%SXqJW^:
r; !us~
5S bSz!s`$
c2"OpI
2. 编写业务逻辑接口,并实现它(UserManager, YN[D^;}
'?t{-z,
UserManagerImpl)
t-/^ O
java代码: "p\KePc;@
gO36tc:ce
7\lc aC@
/*Created on 2005-7-15*/ u e~1144
package com.adt.service; tnntHQ&b
4V5*6O9(u
import net.sf.hibernate.HibernateException; E)bP}:4V
#D8)rs.9
import org.flyware.util.page.Page; )DMbO"7
3{z }[@N
import com.adt.bo.Result; >EjBknl
b-XBs7OAx
/** FliN@RNo
* @author Joa "`zw(
*/ |kD?^Nx
publicinterface UserManager { T^W8_rm*3
&bb*~W-
public Result listUser(Page page)throws on|>"F`pb
u#QQCgrs
HibernateException; 'WoX-y
Sob+l'U$
} 2J$Uz,@
gnt[l0m
7 m%|TwJN
@VFg XN
j43HSY7@
java代码: xhv)rhu@
~mU#u\r(*
=n!8>8d
/*Created on 2005-7-15*/ klKt^h-
package com.adt.service.impl; Q_S
fFsY
3? "GH1e
import java.util.List; oc.x1<Nd
(RF6K6~
import net.sf.hibernate.HibernateException; ;(A'XA4
6N
<?eZ9eB
import org.flyware.util.page.Page; 4*]`s|fbu
import org.flyware.util.page.PageUtil; ;lldxS
>:Ec
import com.adt.bo.Result; -J:vYhq|g
import com.adt.dao.UserDAO; &o(?
}W
import com.adt.exception.ObjectNotFoundException; XOoND
import com.adt.service.UserManager; (1R,
99x]DY
/** <K~#@.^`
* @author Joa |<S9nZg%p
*/ (fl2?d5+C
publicclass UserManagerImpl implements UserManager { r mhB!Lo
;X>KP,/r$
private UserDAO userDAO; /D~:Ufw
Vs(;al'
/** yl*S|= 8;k
* @param userDAO The userDAO to set. U i;o/Z3
*/ 6Dch+*4*@
publicvoid setUserDAO(UserDAO userDAO){ >13= 4S
this.userDAO = userDAO; 'RhMzPmY>
} n*V^Qf
7 @ZL(G
/* (non-Javadoc) /3fo=7G6
* @see com.adt.service.UserManager#listUser *E>YLkg]
LY"/ Q
(org.flyware.util.page.Page) [}Nfs3IlBw
*/ (jXgJ" m
public Result listUser(Page page)throws ?tOzhrv
;2$^=:8
HibernateException, ObjectNotFoundException { ky*-_
int totalRecords = userDAO.getUserCount(); #nnP.t m
if(totalRecords == 0) @|M10r9E
throw new ObjectNotFoundException I".r`$XZ
6@ +
>UZr\
("userNotExist"); r$+9grm<
page = PageUtil.createPage(page, totalRecords); b'G4KNW
List users = userDAO.getUserByPage(page); 6SpkeXL
returnnew Result(page, users); N$.''D?7D
} edch'H^2+P
@0aUWG!k
} $0WAhq
s%Z3Zj(,8(
mZORV3bN
,ihTEw,t(
a/_ `1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 3Z`oI#-x
4Hu.o 7
询,接下来编写UserDAO的代码: ^0VI J)y
3. UserDAO 和 UserDAOImpl: *Owq_)_(|
java代码: UO</4WJ
K[sfsWQ.
y- g5`@
/*Created on 2005-7-15*/ &u8BGMl2
package com.adt.dao; <yeG0`}t
:R_(+EK1
import java.util.List;
pNDL:vMWP
0 {w?u %'
import org.flyware.util.page.Page; t4nAy)I)P
%_5B"on
import net.sf.hibernate.HibernateException; %H:!/'45
WL>"hkx
/** Yx,
* @author Joa P
/Js!e<\
*/ TkK- r(=
publicinterface UserDAO extends BaseDAO { M6?* \9E
!X8:#a(
publicList getUserByName(String name)throws a7Z PV1k
kfn5y#6NZ
HibernateException; k;"=y)@o
h:l\kr|9
publicint getUserCount()throws HibernateException; 2;A].5>l
,]>Eg6B,u
publicList getUserByPage(Page page)throws nF05p2Mh
{>Zc#U'
HibernateException; ]zu"x9-`
zK33.HY
} #b:8-Lt:M
kz+P?mopm
a(bgPkPP
.HMO7n6)8l
R}*e% EG/
java代码: %3Y&D]
6kHAoERp
iN_G|w[d
/*Created on 2005-7-15*/ !J.qH%S5
package com.adt.dao.impl; m7fmQUk
ze]2-B4
import java.util.List; P#6y
Ig]Gg/1G
import org.flyware.util.page.Page; qbmy~\ZY
t(^c]*r~
import net.sf.hibernate.HibernateException; POdG1;)
import net.sf.hibernate.Query; 5PG%)xff*
8LB+}N(8f
import com.adt.dao.UserDAO; |eJ4"OPC
M&xfQNE
/** m>~%.
(/x
* @author Joa F.K7w
*/ m@)K]0g<f
public class UserDAOImpl extends BaseDAOHibernateImpl 59IxY
?
J'|qFS
implements UserDAO { 5|";L&`
nRJcYl~
Y
/* (non-Javadoc) Td}#o!4!
* @see com.adt.dao.UserDAO#getUserByName _yumUk-QW
]k5l]JB
(java.lang.String) 8I3"68c_a
*/ jCxw|tmgq
publicList getUserByName(String name)throws q@H?ohIH
3S ,D~L^
HibernateException { NFv9%$l-
String querySentence = "FROM user in class ]_@5LvI
W& w-yZ
com.adt.po.User WHERE user.name=:name"; Xh;Pbm|K
Query query = getSession().createQuery t(}\D]mj
k?KKb
/&b
(querySentence); #O*
ytZ
query.setParameter("name", name); 3w#kvtDVm
return query.list(); +-1t]`9k4
} #toKT_
1
@tVfn}
/* (non-Javadoc) Y[#i(5w
* @see com.adt.dao.UserDAO#getUserCount() "8>*O;xk
*/ Ns?y)
G>:
publicint getUserCount()throws HibernateException { H"6Sj-<=
int count = 0; w-pdpbHV
String querySentence = "SELECT count(*) FROM ]G#og)z4
t?iCq1
user in class com.adt.po.User"; v=$v*W
Query query = getSession().createQuery ]z;%%'gW6
*^ g7kCe(
(querySentence); T]Pp\6ff
count = ((Integer)query.iterate().next ORD@+ {
" P c"{w
()).intValue(); %s6|w=.1
return count; !O~EIz
} y4^6I$M7V
!inonR
/* (non-Javadoc) l
2y_Nz-;
* @see com.adt.dao.UserDAO#getUserByPage Zqc+PO3lw
T}jryN;J5
(org.flyware.util.page.Page) a`|&rggN
*/ J.N%=-8
publicList getUserByPage(Page page)throws 8HS1^\~(6l
`9SuDuw;s
HibernateException { -Xb]=Yf-
String querySentence = "FROM user in class ]W-l1
P33x/#VVE
com.adt.po.User"; u(S~V+<@Z
Query query = getSession().createQuery v `9IS+Z
2&S*> (
(querySentence); n(\5Z&
query.setFirstResult(page.getBeginIndex()) HZ* <BjE:"
.setMaxResults(page.getEveryPage()); VQI
return query.list(); 9
N[k ?kUZ
} c$ya{]a
ov.7FZ+
} 6&5p3G{%0
I4.^I/c(
5B)Z@-x2
B[w~bW|K
p)NhV
至此,一个完整的分页程序完成。前台的只需要调用 WLqwntzk
%{Ez0XwGCn
userManager.listUser(page)即可得到一个Page对象和结果集对象 S7vT=
df; -E
的综合体,而传入的参数page对象则可以由前台传入,如果用 PBc.}TSGj
x<W`2Du
webwork,甚至可以直接在配置文件中指定。 R/&Bze
,{!~rSq-l
下面给出一个webwork调用示例: W7r1!/ccj
java代码: Ju4={^#
Lwm2:_\_b
cPZD#";f
/*Created on 2005-6-17*/ )>abB?RZ
package com.adt.action.user; :yO.Te
F
u^&2T(xGi
import java.util.List; P]hS0,sE<(
h)2W}p{a4=
import org.apache.commons.logging.Log; dP}=cZ~
import org.apache.commons.logging.LogFactory; KAH9?zI)M
import org.flyware.util.page.Page; 2A'!kd$2
U`Bw2Vdk]S
import com.adt.bo.Result; Uv?s <
import com.adt.service.UserService; Q$r1beA
import com.opensymphony.xwork.Action; ('BFy>@
OLp;eb1g
/** J-yj&2
* @author Joa aUUr&yf_L
*/ ;dgxeP;mp
publicclass ListUser implementsAction{ #
Un>g4>Rh
:I*G tq
privatestaticfinal Log logger = LogFactory.getLog |d =1|C%,
o\6A]T=R
(ListUser.class); f.SV-{O_
x@/ N9*
private UserService userService; h.+{cOA;n
Gu?OyL
private Page page; %GG:F^X#
t '
_Au8
privateList users; p w(eWP
r6k0=6i
/* xLhN3#^m
* (non-Javadoc) S3EM6 `q'
* F=)9z+l#
* @see com.opensymphony.xwork.Action#execute() Ln-/
9'^
*/ ~H"Q5Hr
publicString execute()throwsException{ %6r MS}
Result result = userService.listUser(page); ,[fn? s r
page = result.getPage(); Nb;xJSl ox
users = result.getContent(); l,5<g-r
V
return SUCCESS; l+g\xUP
} A<-Prvryt
5=]q+&y\H
/** r#ES|
* @return Returns the page. xDv5'IGBb
*/
x|C[yu^c
public Page getPage(){ I{#&!h>]U
return page; T;!7GW4E
?
} pt[H5
.PjJ g^^
/** 4JF)w;X}
* @return Returns the users. mHcxK@qw
*/ e`gOc*
publicList getUsers(){ IRy!8A=X
return users; ::bK{yZm
} fNjxdG{a
=fk+"!-i%"
/** %@JNX}Y'
* @param page .
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* The page to set. LS1r}cl
*/ 5cLq6[uO
publicvoid setPage(Page page){ }2dz];bR
this.page = page; Bc1[^{`bq^
} bMWL^ *I
\GA6;6%Oo
/** s%Ez/or(T
* @param users I{>U 7i
5
* The users to set. N$#518
*/ }py6H[
publicvoid setUsers(List users){ 9e^HTUFbG
this.users = users; $x_6
.AOZ,
} *]uo/g
LObS
7U
/** H(f~B<7q
* @param userService rzmd`)g
* The userService to set. (pY'v/ a-
*/ w#V{'{DKp
publicvoid setUserService(UserService userService){ "{a-I=s\C
this.userService = userService; Vy*&po[
} X;$g7A
} :0K[fBa
}*vUOQQp*
/>1Ndj
/58]{MfrJ
q:Lw!'Zh
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, N^i<A2'6S;
}~gBnq_DDU
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 S0X%IG
E+XpgR5
么只需要: 8)I,WWj
java代码: UuDT=_1Sh
m(Hb! RT
Fqtgw8
<?xml version="1.0"?> FFE IsB"9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fAx7_}k/ m
"&jWC
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;qM
I3 wF
InI^,&<
1.0.dtd"> M9mC\Iz[
M7D@Uj&xx(
<xwork> 9OIX5$,S;
&S\q*H=}i
<package name="user" extends="webwork- @WcK<Qho
(W*~3/@D
interceptors"> {\tHS+]
^A9D;e6!-
<!-- The default interceptor stack name K(*QhKX
%EC{O@EAk
--> R <kh3T
<default-interceptor-ref %<^B\|d'?
\SB~rz"A
name="myDefaultWebStack"/> ]-
ce/Z[B+d
<action name="listUser" f-at@C1L%L
%onUCN<O`
class="com.adt.action.user.ListUser"> g? 7%
<param AGwFD
/SLAg&
name="page.everyPage">10</param> e_Cns&
<result HS1Gy/6'
;Od;q]G7L
name="success">/user/user_list.jsp</result> "S$4pj`<
</action> x,kZ>^]&b
[X >sG)0S~
</package> ] r8
hMv
" oWiQ{\IP
</xwork> <28L\pdG`
qw]:oh&G
,~;_-
I]S8:w![
%lL^[`AR
7"L`|O?8)
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 +q z"+g
FcR(uv<
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 hY5G=nbO*
VUfV=&D-*g
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3Q-i%7l
oBVYgv)
OG\TrW-ug
%m\dNUz4g
,^dyS]!d$
我写的一个用于分页的类,用了泛型了,hoho _J<^'w^;%
P%Fkd3e+
java代码: yn;h.m [):
V?{[IMRC
-49z.(@ki
package com.intokr.util; d1=kHU4_9
=F>@z4[P-
import java.util.List; MGUzvSf
7
S^iGe
/** ?sb
Ob
* 用于分页的类<br> p h[
^ve
* 可以用于传递查询的结果也可以用于传送查询的参数<br> z"`q-R }m
* 3`9H
* @version 0.01 ]6wo]nV[P
* @author cheng eQBR*@x
*/ I+ZK \?Rs
public class Paginator<E> { =ytB\e
privateint count = 0; // 总记录数 '\[o>n2
privateint p = 1; // 页编号 kNX"Vo]1
privateint num = 20; // 每页的记录数 ^X$k<n A;
privateList<E> results = null; // 结果 igNZe."V
#q2cVN1
/** YyR)2j1O
* 结果总数 Aj`zT'
*/ 5B+>28G%
publicint getCount(){ >Le L%$
return count; _c}@Fi+E
} R-Y |;
rDNz<{evj
publicvoid setCount(int count){ k(Z+(Y'{q~
this.count = count; /|{Yot
e
} y=!"++T]B<
p1B~:9y9X
/** XW!a?aLNX
* 本结果所在的页码,从1开始 k(n{$
* &m=Xg(G~c
* @return Returns the pageNo. }{Y)[w#R
*/ (<?6X9F:N
publicint getP(){ V=";vRS8
return p; ?2ZggV
} b-}nv`9C
>h3r\r\n3
/** )+]8T6~
N
* if(p<=0) p=1 q$vATT
* b2OVg
+3
* @param p F.P4c:GD
*/ !;'.mMO&%
publicvoid setP(int p){ r&AX
if(p <= 0) =2HR+
p = 1; &
[)1LRt_
this.p = p; e|:#Y^
} N>z<v\`
b2;+a(
/** k/+-Tq;
* 每页记录数量 O[O`4de9
*/ 9W$d'IA
publicint getNum(){ +QNFu){G
return num; $~UQKv>
} AJ-p|[wPz
"kC uCc
/** [jl'5l d
* if(num<1) num=1 Uf^zA/33
*/ Kg0Vbzvb
publicvoid setNum(int num){ G_E U/p<Q
if(num < 1) ~.qzQ_O/
num = 1; wN,DTmtD
this.num = num; m=&j2~<i
} ODn6%fp%
rK%<2i
/** ajIgL<x
* 获得总页数 5Z{h!}Y
*/ %AbA(F
publicint getPageNum(){ J{$+\
return(count - 1) / num + 1; h?wNmLre
} ]=v_u9;
m x@F^
/** y=y=W5#;77
* 获得本页的开始编号,为 (p-1)*num+1 FoM4QO
*/ f(.@]eu
X
publicint getStart(){ reml|!F-)
return(p - 1) * num + 1; 6x KbK1W
} }>vf(9sF`
wD>tR
SW
/** SX)giQLU
* @return Returns the results. c)8V^7=Q
*/ &0*l=!:G^
publicList<E> getResults(){ }J}a;P4
return results; c-z2[a8
} -L>\ 58`
WN9<
public void setResults(List<E> results){ q0Fq7rWP
this.results = results; ZN!OM)@:!
} ?vL\VI9
=G9%Hz5~:
public String toString(){ a~YFJAkg9
StringBuilder buff = new StringBuilder L-_dq0T
0;z-I"N
(); yoTbIQ
buff.append("{"); (A2x
buff.append("count:").append(count); Y(IT#x?p
buff.append(",p:").append(p); Vm.&JVb
buff.append(",nump:").append(num); UF)rBAv(/
buff.append(",results:").append Zd@'s.,J
LO@.aJpp
(results); %Kd&A*
buff.append("}"); 5T,Doxo
return buff.toString(); gwk$|aT@
} ia15r\4j)
<{@?c
} MdK!Y
.J' 8d"+
4?XX_=+F|