Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .gZZCf&?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 igDyp0t
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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 >HkhAJhW
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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 a}.Y!O&
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分页支持类: CdhSp$>
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java代码: Pl~P- n
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package com.javaeye.common.util; K^i"9D)A
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import java.util.List; ^GXEJU7U
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publicclass PaginationSupport { )bWrd$X
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publicfinalstaticint PAGESIZE = 30; oK-!(1A-
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privateint pageSize = PAGESIZE; !
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privateList items; UxPGv;F
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privateint totalCount; t9*=
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privateint[] indexes = newint[0]; $N.`)S<
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privateint startIndex = 0; 52<~K
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public PaginationSupport(List items, int _.f@Y`4d
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totalCount){ {,V$*
setPageSize(PAGESIZE); QAaF@Do
setTotalCount(totalCount); dF2@q@\.+
setItems(items); w#{l4{X|
setStartIndex(0); Oc-u=K,B
} +{&+L0DfH~
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public PaginationSupport(List items, int |a(Q4 e/,
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totalCount, int startIndex){ U(3(ZqP
setPageSize(PAGESIZE); /oDpgOn
setTotalCount(totalCount); IgA.%}II}
setItems(items); aiR5/
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setStartIndex(startIndex); %AgA -pBp
} 83?1<v0%
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public PaginationSupport(List items, int BQU/Qo DY
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totalCount, int pageSize, int startIndex){ nhT;b,G.Z
setPageSize(pageSize); {jG.=}/Dk
setTotalCount(totalCount); S2}Z&X(
setItems(items); Z3n~&!
setStartIndex(startIndex); afy/K'~
} >e_%M50
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publicList getItems(){ 5h(jeT8"
return items; B$DZ]/<
} ^cb)f_90
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publicvoid setItems(List items){ 7%tR&F -u
this.items = items; i ha9!kf
} _y-B";Vmm
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publicint getPageSize(){ 0k.v0a7%
return pageSize; :B+Rg cqi
} n`QO(pZ6+
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publicvoid setPageSize(int pageSize){ .o"<N
this.pageSize = pageSize; pzAoq)gg:
} 9c6 '
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publicint getTotalCount(){ 5Fr;
return totalCount; fo;6huz
} m1i4 ,
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publicvoid setTotalCount(int totalCount){ k~R{Y~W!!
if(totalCount > 0){ |""=)-5N
this.totalCount = totalCount; '6+Edu~Ho)
int count = totalCount / + q
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pageSize; )ib7K1GJ
if(totalCount % pageSize > 0) _o&94&
count++; 7|K3WuLL
indexes = newint[count]; sK `<kbj
for(int i = 0; i < count; i++){ \a?K?v|8
indexes = pageSize * x'zihDOI
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i; q;ZLaX\bFl
} 8s~\iuk
}else{ .hc|t-7f
this.totalCount = 0; \hrrPPD1z
} TZ:34\u
} })KJ60B
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publicint[] getIndexes(){ ,TEuM|
return indexes; _Q)d+Fl
} z;[gEA+I
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publicvoid setIndexes(int[] indexes){ AvyQ4xim+
this.indexes = indexes; r)OO&. P@j
} B>sCP"/uV
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publicint getStartIndex(){ ;*W=c
return startIndex; 3mk=ZWwv
} KUF$h Er
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publicvoid setStartIndex(int startIndex){ #FEa 5
if(totalCount <= 0) h (qshbC}
this.startIndex = 0; `0Yt1Z&
elseif(startIndex >= totalCount) XO 0>t{G
this.startIndex = indexes D*CIE\+
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[indexes.length - 1]; c/b%T
elseif(startIndex < 0) f( ]R/'o
this.startIndex = 0; ri#,ec|J
else{ ri"?,}(
this.startIndex = indexes 9!5b2!JL
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[startIndex / pageSize]; ?hxK/%)
} sP9 ^IP
} wDB)&b
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publicint getNextIndex(){ Y=5!QLV4
int nextIndex = getStartIndex() + {`+bW"9
#D/$6ah~m
pageSize; Bh\
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if(nextIndex >= totalCount) $eK8GMxZ#
return getStartIndex(); /uC+.B9k
else 2ZU@>W
return nextIndex; PZKbnu
} p^p'/$<6_
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publicint getPreviousIndex(){ dD[v=Z_
int previousIndex = getStartIndex() - bs:C1j\&
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pageSize; ;~}-AI-
if(previousIndex < 0) d8xk&za
return0; [P.@1mV
else w;lx:j!Vp$
return previousIndex; 9QX&7cs&[
} M/n[&
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} N5:D8oWWXR
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抽象业务类 Xulh.:N}
java代码: #nU@hOfg
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/** ?3]h~(=
* Created on 2005-7-12 H=JP3ID>{
*/ H j>L>6>
package com.javaeye.common.business; FiV^n6-F`
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import java.io.Serializable; V/QTYy1
import java.util.List; d+gk q\
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import org.hibernate.Criteria; }0k"SwX
import org.hibernate.HibernateException; 9b{g+lMZo
import org.hibernate.Session; >i><s>=I`
import org.hibernate.criterion.DetachedCriteria; ')C_An>X6
import org.hibernate.criterion.Projections; /t%"Dh8x
import Q1N,^71
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org.springframework.orm.hibernate3.HibernateCallback;
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import % xH>0
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org.springframework.orm.hibernate3.support.HibernateDaoS pAPQi|CN
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upport; a=}">=]7
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import com.javaeye.common.util.PaginationSupport; ^c;skV&S
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public abstract class AbstractManager extends S`'uUvAA
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HibernateDaoSupport { nU">> 1!U
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privateboolean cacheQueries = false; {
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privateString queryCacheRegion; Og%zf1)aZM
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publicvoid setCacheQueries(boolean eBLHT
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cacheQueries){ &Hp\("
this.cacheQueries = cacheQueries; aaqjE
} *YEIG#`
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publicvoid setQueryCacheRegion(String 6|(7G64{
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queryCacheRegion){ P[J qJi/H
this.queryCacheRegion = EC\rh](d
1
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queryCacheRegion; .q;RNCUt
} Liz6ob
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publicvoid save(finalObject entity){ ?M1 QJ
getHibernateTemplate().save(entity); hTNYjXj
} ^PCL^]W
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publicvoid persist(finalObject entity){ |SJ%
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getHibernateTemplate().save(entity); N?u2,h-
} Wf&G9Be?8
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publicvoid update(finalObject entity){ {t IoC;Y
getHibernateTemplate().update(entity); K+aJ`V
} TJGKQyG$L
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publicvoid delete(finalObject entity){ -<VF6k<
getHibernateTemplate().delete(entity); V1+o3g{}
} R/KWl^oNj
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publicObject load(finalClass entity, 3T#3<gqM[
}X.8.S'
finalSerializable id){ p44uozbK
return getHibernateTemplate().load F@*r%[S/
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(entity, id); ;U:o'9^9T
} hE3jb.s(>
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publicObject get(finalClass entity, {&AT}7
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finalSerializable id){ &cv/q$W4
return getHibernateTemplate().get &T4Cn@
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(entity, id); @RG3*3(
} Ra,on&OP`*
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publicList findAll(finalClass entity){ &[\arwe)
return getHibernateTemplate().find("from !P3tTL!*L
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" + entity.getName()); 6/[h24d
} Q0cf]
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publicList findByNamedQuery(finalString 4w
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namedQuery){ J'oz P^N
return getHibernateTemplate Z|7I }i
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().findByNamedQuery(namedQuery); 6I'VXdeN
} W;j)ux7jMY
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publicList findByNamedQuery(finalString query, u(Q(UuI
(?=(eo<N
finalObject parameter){ p~y
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return getHibernateTemplate %x)U8
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().findByNamedQuery(query, parameter); "alO"x8t
} 1>*<K/\qg
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publicList findByNamedQuery(finalString query, 2QD
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finalObject[] parameters){ oieLh"$
return getHibernateTemplate y3$\ m
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().findByNamedQuery(query, parameters); MZ[g|o!)v
} jWjK -q@Y
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publicList find(finalString query){ x}24?mP
return getHibernateTemplate().find ]nGA1 S{
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(query); '4S@:.D`
} Vc<n6
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publicList find(finalString query, finalObject .=<pU k 3G
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parameter){ 9%veUvY
return getHibernateTemplate().find f;6d/?= ~
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(query, parameter); uZI:Kt#
} Y&%0 eI!
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public PaginationSupport findPageByCriteria p#NZ\qJ
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(final DetachedCriteria detachedCriteria){ 1a4 $.
{
return findPageByCriteria V,,iKr@TG
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Qc/J"<Lx
} B*Xh$R
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public PaginationSupport findPageByCriteria qa#F}aGd
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(final DetachedCriteria detachedCriteria, finalint <<6#Uz.1
"aH]4DO
startIndex){ )^3655mb
return findPageByCriteria VUhu"h@w%
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(detachedCriteria, PaginationSupport.PAGESIZE, ~0:c{v;4
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startIndex); 5T*7HC[
} U{m:{'np(H
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public PaginationSupport findPageByCriteria $80/ub:R
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(final DetachedCriteria detachedCriteria, finalint 2j|Eh
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pageSize, CdjGYS
finalint startIndex){ 21Opx~T3
return(PaginationSupport) T!r7RS
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getHibernateTemplate().execute(new HibernateCallback(){ tc Z~T
publicObject doInHibernate Nq3P?I(<
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(Session session)throws HibernateException {
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Criteria criteria = Fh;(1X75I
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detachedCriteria.getExecutableCriteria(session); 6cvm\opH
int totalCount = ,\IZ/1
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((Integer) criteria.setProjection(Projections.rowCount FB`HwE<
=nl,5^
()).uniqueResult()).intValue(); 7085&\9
criteria.setProjection {,ljIhc,
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IF
(null); i)ctrdP-
List items = ,v+SD\7|
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criteria.setFirstResult(startIndex).setMaxResults .nN7*))Fj
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(pageSize).list(); pOXEM1"2A
PaginationSupport ps =
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new PaginationSupport(items, totalCount, pageSize, S/|8'x{<
,??|R`S
startIndex); GupKM%kM
return ps; z&8#1'
} bhRpYP%x
}, true); ~F-,Q_|-
} e;$s{CNo
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public List findAllByCriteria(final *MNY1+RJ
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DetachedCriteria detachedCriteria){ %k~=iDk@
return(List) getHibernateTemplate 7RZ7q@@fgh
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().execute(new HibernateCallback(){ Z,z^[Jz
publicObject doInHibernate Nb6HM~
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(Session session)throws HibernateException { bF.Aj8ZQ
Criteria criteria = Ok@5`?08
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detachedCriteria.getExecutableCriteria(session); _Cxs"to
return criteria.list(); |7 argk+
} bFpwq#PDW>
}, true); L\UYt\ks
} zK&`&("4C
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public int getCountByCriteria(final ^6=nL<L
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DetachedCriteria detachedCriteria){ CAX U
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Integer count = (Integer) tP\Utl-0
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getHibernateTemplate().execute(new HibernateCallback(){ ~Oq(JM
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publicObject doInHibernate p(Sfw>t(
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(Session session)throws HibernateException { bV"0}|A~K
Criteria criteria = -6?5|\
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detachedCriteria.getExecutableCriteria(session); qU"+0t4
return A
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criteria.setProjection(Projections.rowCount &0
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()).uniqueResult(); q|~9%Pujg
} P^
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}, true); |2mEowAd
return count.intValue(); pvX\kX3}
} t({:TQ
} C&Rv)j
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用户在web层构造查询条件detachedCriteria,和可选的 Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2 Y%$6NX
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PaginationSupport的实例ps。 N/Z<v* i"
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ps.getItems()得到已分页好的结果集 4re^j4L~o
ps.getIndexes()得到分页索引的数组 Oq[tgmf
ps.getTotalCount()得到总结果数 90Q}9T\
ps.getStartIndex()当前分页索引 (}'0K?
ps.getNextIndex()下一页索引 .Zo8KwkFY
ps.getPreviousIndex()上一页索引 #\fApRL
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7GpSWM6
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 TTS}, `
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一下代码重构了。 9^XT,2Wwf
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我把原本我的做法也提供出来供大家讨论吧: 7n5bI\
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首先,为了实现分页查询,我封装了一个Page类: bq]af.o*
java代码: )0YMi!&j`
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/*Created on 2005-4-14*/ ` O-$qT,_
package org.flyware.util.page; YaDr6)
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/** A6=
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* @author Joa Vf,t=$.[Q
* VQ2)qJ#l
*/ MX]<tR `
publicclass Page { l\JoWL
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/** imply if the page has previous page */ P'R!"
#
privateboolean hasPrePage; [*Wq6n
BNnGtVAbZ
/** imply if the page has next page */ bR(rZu5
privateboolean hasNextPage; L6O*aZ|
&dH/V-te
/** the number of every page */ KYZ/b8C
privateint everyPage; 0PjWfM8%
[g`P(?
/** the total page number */ %[l5){:05
privateint totalPage; p$0G EYwM
`,3;#.[D
/** the number of current page */ /z.Y<xOc
privateint currentPage; TW"
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/** the begin index of the records by the current WnyEdYA
nRzD[3I
query */ YAYPof~A$l
privateint beginIndex; TmxhP
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/** The default constructor */ ZEYT17g]
public Page(){ C4Z}WBS(
)v
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} R?Vs8?
@GNNi?EY
/** construct the page by everyPage #N.W8mq
* @param everyPage G>&Ta p>
* */ j^-E,YMC
public Page(int everyPage){ 1t w>C\
this.everyPage = everyPage; Uus%1hC%a
} ^lud2x$O^C
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/** The whole constructor */ 0}tf*M+a
public Page(boolean hasPrePage, boolean hasNextPage, gG*]|>M JI
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# bc$[%_
int everyPage, int totalPage, )WuU?Tn&
int currentPage, int beginIndex){ (&t741DN|
this.hasPrePage = hasPrePage; K9O%SfshF
this.hasNextPage = hasNextPage; BPs|qb-
this.everyPage = everyPage; ;n]GHqzY_
this.totalPage = totalPage; u5zL;C3O
this.currentPage = currentPage; g^ .g9"
this.beginIndex = beginIndex; O=m_P}K
} Se~<Vpo
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/** @pq2Z^SQ H
* @return :x88
* Returns the beginIndex. R<(kiD\?]
*/ J,q6
publicint getBeginIndex(){ bvn%E
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return beginIndex; ,'!x9 `
} v3\
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/** |p_\pa1&
* @param beginIndex 8[v9|r
* The beginIndex to set. [l#
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*/ "-
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publicvoid setBeginIndex(int beginIndex){ ={g.Fn(_
this.beginIndex = beginIndex; R%Xhdcn7
}
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/** vtx3a^
* @return r{LrQ
* Returns the currentPage. D@W[Nd5MJ
*/ ;@ <E
publicint getCurrentPage(){ '0b!lVe
return currentPage; "R< c
} >;qAj!'
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/** Y9<N#h#
* @param currentPage xgp 6lO [
* The currentPage to set. 2eC`^
*/ ,]Gi942
publicvoid setCurrentPage(int currentPage){ 3[{RH*nHD
this.currentPage = currentPage; <ztcCRov
} jK(]eiR$S
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/** ~SzHIVj:6
* @return g$/C-j4A[
* Returns the everyPage. 7=hISQMsVP
*/ hnYL<<AA
publicint getEveryPage(){ 57|RE5]|!
return everyPage; 18eB\4NlD
} #jqcUno
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/** ztEM>xsk
* @param everyPage PKjM1wqaG@
* The everyPage to set. wH0m^?a!3
*/ 0FAe5
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publicvoid setEveryPage(int everyPage){ XM#xxf* Y
this.everyPage = everyPage; Ht,+KbB
} ).$q9G
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/** (5/>arDn
* @return Gnthz0\]{
* Returns the hasNextPage. w7E7r?)Wl|
*/ ^'G,sZ6'Nh
publicboolean getHasNextPage(){ #S|DoeFs
return hasNextPage; Dg=!d)\
} ]EWEW*'j
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/** PZ.q
* @param hasNextPage NsN =0ff
* The hasNextPage to set. ^q}cy1"j"
*/ BM>'w,$KL
publicvoid setHasNextPage(boolean hasNextPage){ _&R lR
this.hasNextPage = hasNextPage; gp(: o$
} %0Mvd;#[
cii!
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/** U9t-(`[j?
* @return Z=.$mFE\
* Returns the hasPrePage. lF#p1H>\
*/ %1Nank!Zj
publicboolean getHasPrePage(){ kn9e7OO##
return hasPrePage; w!--K9
} 61pJVOe
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/** u`
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* @param hasPrePage *LOUf7`
* The hasPrePage to set. i$gH{wn\`
*/ $'%.w|MJp
publicvoid setHasPrePage(boolean hasPrePage){ J.Fy0W@+k4
this.hasPrePage = hasPrePage; E(-@F%Q
} $mu*iW\{
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/** :lE_hY
* @return Returns the totalPage. VdOcKP.
* @<ILF69b
*/ | IB4-p
publicint getTotalPage(){ }8eu 9~
return totalPage; /Bs42uJ3
} _%]x-yH!@
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/** 73kU\ux
* @param totalPage o"j$*o=
* The totalPage to set. 3%L@=q
*/ h/pm$9A
publicvoid setTotalPage(int totalPage){ TGH"OXV*@
this.totalPage = totalPage; z(eAhK}6?
} g T{WH67u
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} +x]3 -s
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 *ry}T=
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个PageUtil,负责对Page对象进行构造: {1;R&
java代码: 2(AuhZ>
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/*Created on 2005-4-14*/ b_Dd$NC
package org.flyware.util.page; g[Q+DT
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import org.apache.commons.logging.Log; KBa ]s q_
import org.apache.commons.logging.LogFactory; t.Yf8Gy
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/** ./35_Vy/O
* @author Joa Ajm4q_
* vYg>^!Q
*/ yJ4ZB/ZQ
publicclass PageUtil { B!1h"K5.($
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privatestaticfinal Log logger = LogFactory.getLog 6d(D>a
G@zJf)u}
(PageUtil.class); TPVB{
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/** s#H_QOE
* Use the origin page to create a new page SW}?y%~
* @param page Rga
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* @param totalRecords \Oxyc}&
* @return #z+?t
*/ 8.:WMH`
publicstatic Page createPage(Page page, int [@_W-rA
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totalRecords){ *yv@B!r
return createPage(page.getEveryPage(), xqb*;TBh*
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page.getCurrentPage(), totalRecords); F*T$n"^
} 20# V?hX3
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/** qrf90F)
* the basic page utils not including exception i5aY{3!
h[mJ=LIrg
handler V8#NXUg<!
* @param everyPage 7,zE?KG /
* @param currentPage ~=Q^]y,
* @param totalRecords J0Gjo9L
* @return page Y,Lx6kU
*/ GVhy
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publicstatic Page createPage(int everyPage, int p zZ+!d
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;
currentPage, int totalRecords){ /+1(,S
everyPage = getEveryPage(everyPage); VeSQq
currentPage = getCurrentPage(currentPage); b:cy(6G(
int beginIndex = getBeginIndex(everyPage, VVDW=G
Nz}PcWF/
currentPage); D^gS.X ^
int totalPage = getTotalPage(everyPage, ac\( [F-
6bPl(.(3
totalRecords); C57m{RH
boolean hasNextPage = hasNextPage(currentPage, u-_1)'
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totalPage); +~~2OU L
boolean hasPrePage = hasPrePage(currentPage); Z&79: 9=#>
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-
returnnew Page(hasPrePage, hasNextPage, oEX^U4/=
everyPage, totalPage, AVm+
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currentPage, T2 S fBs
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beginIndex); s_a jA
} NJ]3qH
0)M8Tm0$
privatestaticint getEveryPage(int everyPage){ bAbR0)
return everyPage == 0 ? 10 : everyPage; tJ
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} N/ f7"~+`
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privatestaticint getCurrentPage(int currentPage){ T@Y, 7ccpd
return currentPage == 0 ? 1 : currentPage; 9?8PMh.
} tU5uL.( O
UoPY:(?;i
privatestaticint getBeginIndex(int everyPage, int 0{g*\W*+~
0y6M;"&~E
currentPage){ B]@25
return(currentPage - 1) * everyPage; /isalOT
} j:xC\b47"
"VZXi_P
privatestaticint getTotalPage(int everyPage, int DU0/if9.
^lAM /
totalRecords){ 7@
)
int totalPage = 0; 5nUJ9sqA
ZZ7qSyBs?
if(totalRecords % everyPage == 0) I O:*F0
totalPage = totalRecords / everyPage; Qr9;CVW
else dH!z<~
totalPage = totalRecords / everyPage + 1 ; T*f/M
@phVfP"M
return totalPage; KWZhCS?[(
} qh:Bc$S
0]kKF<s
privatestaticboolean hasPrePage(int currentPage){ b:D92pH
return currentPage == 1 ? false : true; MDU#V
} Y.\x.Hg
;~EQS.Qp
privatestaticboolean hasNextPage(int currentPage, )](ls@*
)63
$,y-;$
int totalPage){ 3o%vV*
return currentPage == totalPage || totalPage == P"8Ix
jYFJk&c
0 ? false : true; E4L?4>V@\
} l6ym <V(1p
n7cy[%yT
+cfEyiub
} 3R3H+W0{
#GE]]7:Na
P[2!D)A
S^eem_C
x,!Dd
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。 c3^!S0U
nt#9j',6Rn
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 ~v+kO~
YQn<CjZ8af
做法如下: P.'.KZJ:WD
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %.Ma_4o
Z
.eR1\IAm
的信息,和一个结果集List: ,~1'L6Ri?
java代码: V4:/LNq_]
:V(LBH0
jYHn J}<
/*Created on 2005-6-13*/ d:@+dS
package com.adt.bo; nm-
0%ul6LvM
import java.util.List; ;xZ+1zmL0
2R[v*i^S
import org.flyware.util.page.Page; %MeAa?G-#
mn7I# ~
/** BNfj0e 5b
* @author Joa #\0m(v
*/ 3iCe5VF
publicclass Result { H9mN nZ_k
U.e!:f4{
private Page page; u?=mh`
,/\`Rc^n
private List content; ';tlV
u
;@wa\H[3v2
/** uNN/o}Qx
* The default constructor )|~&(+Q?]
*/ EYT^*1,E*
public Result(){ _:r8UVAT.
super(); q+?&w'8
} -9b=-K.y
:Y99L)+=/
/** Dvg'
* The constructor using fields Kxsd@^E
* U%h.l
* @param page Tn7Mt7 h
* @param content 1)X|?ZD]F
*/ '12m4quO
public Result(Page page, List content){ |]&3*%b@
this.page = page; Wg|6{'a
this.content = content; +^AdD8U
} LIDi0jbrq
3f`Uoh+
/** vMzL+D2)
* @return Returns the content.
b] 5dBZ(
*/ Ua}R3^_)a
publicList getContent(){ f#s 6 'g
return content; NS[ Z@@
} y" =?l
(Y~/9a4X
/** *).
* @return Returns the page. ,a5q62)q
*/ L1kn="5
public Page getPage(){ D[>:az`
return page; L'wR$
} ui?@:=
_{o 3 y"DZ
/** c]*yo
* @param content ~BI`{/O=
* The content to set. o "r
*/ Ic3a\FTr\
public void setContent(List content){ 1feVFRx'
this.content = content; ub?dfS9$_
} u&*[
T>'w]wi
/** =sWK;`
* @param page V dJ
* The page to set. J{4=:feIC?
*/ 2z;nPup,
publicvoid setPage(Page page){ >_Tyzl>z
this.page = page; 56Lxr{+X
} IfH/~EtX
} OTYkJEC8\N
Lq3<&$
VK/L}^=GOO
m2m
;|rr
;Qt%>Uo8
2. 编写业务逻辑接口,并实现它(UserManager, n%WjU)<
N(i.E5&9
UserManagerImpl) ByE@4+9
java代码: bRggt6$z
8yIBx%"4MH
E;H9]*x/
/*Created on 2005-7-15*/ [kkhVi5;A
package com.adt.service; SDbkPx
_|; d
D
import net.sf.hibernate.HibernateException; i\uj>;B
OGW3Pe0Z'
import org.flyware.util.page.Page; jc3Q3Th/zn
NVQ.;" 2w
import com.adt.bo.Result; Fsl="RB7f
\R9izuc9
/** l_;6xkv4
* @author Joa ]D~Ibv{Y
*/
ld"rL6
publicinterface UserManager {
K#6@sas
/)RH-_63
public Result listUser(Page page)throws W9}
,f
+P9eE,WR
HibernateException; ZJ+ad,?,
E>/~:
} G]$EIf'
?c8(<_I+
W8x&:5Fc)3
iDcYyNE
# bjK]+
java代码: p7{H
"AC
LB({,0mcX
;,uATd|
/*Created on 2005-7-15*/ V^!^wLLi
package com.adt.service.impl; s1sn,?
Xk'Pc0@a
import java.util.List; CY.92I@S
B1Pi+-t
import net.sf.hibernate.HibernateException; 'C`Ykjf
QrFKjmD<
import org.flyware.util.page.Page; @+~>utr
import org.flyware.util.page.PageUtil; [+l6x1Am
v>nBdpjXh
import com.adt.bo.Result; G=Lg5`3;,
import com.adt.dao.UserDAO; Yv)c\hm(7j
import com.adt.exception.ObjectNotFoundException; eU`O=uE
import com.adt.service.UserManager; Qc!3y>Y=_
h-O;5.m-P
/** ai?N!RX%H
* @author Joa `'5vkO>
*/ >z/.8!#Q
publicclass UserManagerImpl implements UserManager { z`$c4p6G6
o%`=+-K
private UserDAO userDAO; Qv'x+GVW]
Q}l~n)=
/** O&y`:#
* @param userDAO The userDAO to set. }kItVx
*/ K1R?Qt,qDF
publicvoid setUserDAO(UserDAO userDAO){ ]9_}S
this.userDAO = userDAO; bWlYQ
} oP4+:r)LKD
f52P1V]
/* (non-Javadoc) \RPwSx
* @see com.adt.service.UserManager#listUser <I2ENo5?
&Ruq8n<
(org.flyware.util.page.Page) h6?Z
*/ %\|{_]h}y
public Result listUser(Page page)throws 3HuGb^SNg
@OFxnF`
HibernateException, ObjectNotFoundException { ;PMh>ZE`
int totalRecords = userDAO.getUserCount(); olL? 6)gC
if(totalRecords == 0) |6^%_kO!|
throw new ObjectNotFoundException IoK/ 2Gp
Px*<-t|R-
("userNotExist"); GP %hf{
page = PageUtil.createPage(page, totalRecords); 4 83rU
List users = userDAO.getUserByPage(page); zA.0Sm
returnnew Result(page, users); < FO=PM
} vp*+Ckd
"dDrw ]P;
} f^"pZS
fn5-Tnsq*
gGM QRRq
:{lP9%J-
SA=>9L,2
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 YOrq)_ l
pz)>y&_o
询,接下来编写UserDAO的代码: SZ$WC8AX
3. UserDAO 和 UserDAOImpl: ^eO/?D8~h
java代码: hh%?E\qM
]cmX f
Z(Y:
/*Created on 2005-7-15*/ ey4.Hj#T
package com.adt.dao; ez*QP|F*9
a@qc?
import java.util.List; (1GU
XM`
H@s7
import org.flyware.util.page.Page; {N/%%O.b
6W=V8
import net.sf.hibernate.HibernateException; $YcB=l
/}L2LMIm
/** PcU~1m1
* @author Joa 6Xm'^T
*/ e3 :L]4t
publicinterface UserDAO extends BaseDAO { Ur>1eN%9'
{)!>e
publicList getUserByName(String name)throws S5y.H
GbL1<P$V
HibernateException; fPPP|
bDtb6hL
publicint getUserCount()throws HibernateException; .#|?-5q/iN
hdrsa}{g
publicList getUserByPage(Page page)throws +>vKI8g*RH
!%('8-x%
HibernateException; 9_O4yTL
pxd=a!(
} wT::b V{
gC/ e]7FNr
VK1B}5 /
l&qCgw
@CL#B98jl
java代码: X
V;j6g
kv3Dn&<rJ
%60 OS3
/*Created on 2005-7-15*/ %|D)%|Z
package com.adt.dao.impl; H%>4z3n
Wx{E\ l
import java.util.List; wLXJ?iy3
SNH 3C1
import org.flyware.util.page.Page; 4.jRTL5-oj
bP9ly9FH
import net.sf.hibernate.HibernateException; ~RuX2u-2&u
import net.sf.hibernate.Query; 6,3o_"J!
d)YlD]I
import com.adt.dao.UserDAO; >{IPt]PCn
tZ9i/ =S
/** bhpku=ov
* @author Joa ] [MtG
*/ 0^-1d2Z~
public class UserDAOImpl extends BaseDAOHibernateImpl Jd>~gA}l
qMNWw\k
implements UserDAO { lZcNio
^}d]O(
/* (non-Javadoc) e}e8WR=B
* @see com.adt.dao.UserDAO#getUserByName RQx8Du<
2L^)k?9>g+
(java.lang.String) ilL0=[2
*/ ,94<j,"
publicList getUserByName(String name)throws `R[ZY!=+
Fr8GGN~/
HibernateException { -[V-f> :
String querySentence = "FROM user in class // o.+?S
$>XeC}"x68
com.adt.po.User WHERE user.name=:name"; ZYwcB]xEz
Query query = getSession().createQuery LmF ,en5
;hX( /T
(querySentence); I9*cEZ!l=e
query.setParameter("name", name); jV3PTU
return query.list(); I#M3cI!X?
} senK(kbc
`Z?wj@H1`
/* (non-Javadoc) ~f1g"
* @see com.adt.dao.UserDAO#getUserCount() )|F|\6:ne
*/ *x"80UXL
publicint getUserCount()throws HibernateException { DmiBM6t3N
int count = 0; )u)=@@k21
String querySentence = "SELECT count(*) FROM _/s"VYFZ
hArY$T&MB
user in class com.adt.po.User"; ~7P)$[
Query query = getSession().createQuery V8?}I)#(7
4>hHUz[_
(querySentence); W lMcEje
count = ((Integer)query.iterate().next j9+$hu#a
u/zBz*zh
()).intValue(); du3f'=q6|
return count; ETe4I`d{
} :HkBP90o
Y`|+sND
/* (non-Javadoc) J-F".6i5
* @see com.adt.dao.UserDAO#getUserByPage "F<CGSo
n|SV)92o1
(org.flyware.util.page.Page) \hB BG8=&
*/ l4Xz r:]
publicList getUserByPage(Page page)throws 'rD6MY
6OES'3 Cy
HibernateException { *eVq(R9?T
String querySentence = "FROM user in class XpIiJry!6
/:&!o2&1H
com.adt.po.User"; _FLEz|%~
Query query = getSession().createQuery 3^ Yc%
24mdhT|
(querySentence); *sho/[~_
query.setFirstResult(page.getBeginIndex()) }I"C4'(a
.setMaxResults(page.getEveryPage()); w2)Ro:G
return query.list(); Hd|l6/[xz
}
`zwz
Wgq|Q*
} (L_-!=e
5jdZC(q5a
[|u^:&az
])x1MmRg\
<#63tN9
至此,一个完整的分页程序完成。前台的只需要调用 WL$^B@gXQ
j=_rUc'Me
userManager.listUser(page)即可得到一个Page对象和结果集对象 mCtS_"W
Pf?kNJ*Tv)
的综合体,而传入的参数page对象则可以由前台传入,如果用 o_b[ *
DT1gy:?L
webwork,甚至可以直接在配置文件中指定。 g;IlS*Ld
^?69|,
下面给出一个webwork调用示例: g8),$:Uw
java代码: 73WSW/^F
.=_p6_G
T X`X5j
/*Created on 2005-6-17*/ r );R/)&
package com.adt.action.user; ZSMed(//b
^6 6!f 5^W
import java.util.List; k_=SDm a
2pS<;k`
import org.apache.commons.logging.Log; fGgt[f[
import org.apache.commons.logging.LogFactory; lG*Rw-?a
import org.flyware.util.page.Page; -DDA b(2*
:fRXLe1=
import com.adt.bo.Result; 0r]n
0?x
import com.adt.service.UserService; B(
[x8A]
import com.opensymphony.xwork.Action; D{|q P
nE4
<QtZ6-;_f
/** ]]xKc5CT
* @author Joa ]5W$EvZ9)
*/ wZrFu(_
publicclass ListUser implementsAction{ 4.6$m
7AG|'s['=
privatestaticfinal Log logger = LogFactory.getLog ;%|im?
NgNGq\!
(ListUser.class); 95 ;{ms[
Jx*cq;`Vee
private UserService userService; B|(g?
H$6RDMU
private Page page; K/4@2vF
>DL
privateList users; $QX$r N
k(Yz2
/* ];r!
M0
* (non-Javadoc) +vc +9E.?9
* A`c22Ls]
* @see com.opensymphony.xwork.Action#execute() Z[vx0[av&
*/ 6)HmE[[F
publicString execute()throwsException{ ~G@NWF?7
Result result = userService.listUser(page); [X(m[u '%
page = result.getPage(); Q @}$b(b
users = result.getContent(); H7O~So*N5
return SUCCESS; u ExLj6
} p l)":}/)
Iil2R}1
/** tZxx#v`
* @return Returns the page. $m`Dyu
*/ .Xg.,kW
public Page getPage(){ whI{?NP
return page; ~$!,-r
} <J%qzt}
Fwm$0=BXL
/** j
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* @return Returns the users. g&RpE41x
*/ WC_.j^sW
publicList getUsers(){ j/v>,MM
return users; 4+olyBht
} v gW(l2,@
y"?`MzcJ0
/** * :"*'
* @param page >=k7#av
* The page to set. s>9I#_4]
*/ %<i sdvF
publicvoid setPage(Page page){ q NGR6i
this.page = page; Kq7r+A
} C&O8fNB_
K#FD$,c~
/** ^Ks1[xc* `
* @param users kV-<[5AWW
* The users to set. QW..=}pL
*/ j;$f[@0o
publicvoid setUsers(List users){ qw+7.h#V
this.users = users; -J]?M
} Y XhZWo{B
o*T?f)_[p
/** R6~6b&-8
* @param userService 9FEhl~&
* The userService to set. [_N1
.}e
*/ pI@71~|R
publicvoid setUserService(UserService userService){ cGE{dWz
this.userService = userService; 9G6)ja?W
} /OKp(u;)z
} U=v>gNba
^;II@n
i
AyJl:aN^
\Y,P
]W3u~T*
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, R0M>'V?e
lG6&uMvo
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 _d!sSyk`
:7@[=n
么只需要: >$kFYb>~q
java代码: mjOxmwo
['QhC( {
%>&~?zrq
<?xml version="1.0"?> .p{lzI9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork TT/=0^"
[KUkv
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5ncW
s)
!fs ~ >
1.0.dtd"> mq{Z
Q'
9#H0|zL
<xwork> $d1ow#ROgy
8y<mHJ[B
<package name="user" extends="webwork- padV|hF3(e
.0nT*LF
interceptors"> oVqx)@$K
BTsvL>Wy
<!-- The default interceptor stack name yS)k"XNb
M5[#YG'FlQ
--> '"Cqq{*
<default-interceptor-ref =$}`B{(H
2SU'lh\E
name="myDefaultWebStack"/> +;H=_~b
pg!mOyn
<action name="listUser" )~P<ruk>,C
kFJ]F |^7
class="com.adt.action.user.ListUser"> uP7|#>1%
<param e?\Od}Hbw
r<]^.]3zj
name="page.everyPage">10</param> depCqz@
<result 'bv(T2d~~
0$XrtnM
name="success">/user/user_list.jsp</result> b5p;)#
</action> p-C{$5&
O1
1>_$O|dE
</package> q89yW)XG
$IKN7
</xwork> WOYZ
AzGbvBI&V
@8YuMD;
fk#Ggp<
M/[9ZgDc
WUDXx %
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 VuBi_v6
U:/_T>f%
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 4J[bh
oOQan
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4!glgEE*
<^Q`
y
xoSBMf
Xp^>SSt:4
sx9[#6~{Y
我写的一个用于分页的类,用了泛型了,hoho [xs`Pi
~O~we
java代码: wS2N,X/Y
or`"{wop
bF@iO316H
package com.intokr.util; Dx3Sf}G
`
KbRKPA`
import java.util.List; zHj_q%A
I>3G"[t
/** 9/\=6vC|
* 用于分页的类<br> FLlL0Gu
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Bsz;GnD|r
* ?y{"OuRf.
* @version 0.01 l5k]voG
* @author cheng DB1Y`l
*/ Y0OVzp9 b
public class Paginator<E> { xeHqC9Ou
privateint count = 0; // 总记录数 HPWjNwM
privateint p = 1; // 页编号 #KSB%
privateint num = 20; // 每页的记录数 [TpW$E0H
privateList<E> results = null; // 结果 i
`8Y/$aT
@l2AL9z$m>
/** jd DcmR
* 结果总数 -Kf'02
*/ [26([H
publicint getCount(){ 7<ES&ls_
return count; !NOvKC!
} /9yA.W;
cXokq
publicvoid setCount(int count){ Ie;}k;?-
this.count = count; >G+?X+9
} 4a~9?}V:
fx4X!(w!B
/** mk~Lkwl
* 本结果所在的页码,从1开始 Vi>kK|\b
* WS0RvBvb
* @return Returns the pageNo. \oGZM0j
*/ :U;ZBs3
publicint getP(){ m;LeaD}0
return p; ~F]- +|
} B6Tn8@O
3' 6>zp
/** ^Sr`)vP
* if(p<=0) p=1 " mE<r2=@
* R\=y/tw0H
* @param p F3a"SKMW
*/ A]vQ1*pnk
publicvoid setP(int p){ Hca)5$yL
if(p <= 0) x2TCw
p = 1; 2S8/
lsB
this.p = p; .,x08M
} }g _#.>D+
Tr}c]IP*
/** 6q8qq/h)
* 每页记录数量 _B|g)Rdv
*/ 413r3/
publicint getNum(){ e:.Xs
return num; bLoYg^T/
} Wm.SLr,o0
BZx#@356N
/** gzHjD-g-<
* if(num<1) num=1 ]0dp^%
*/ rYq8OZLi
publicvoid setNum(int num){ ?(U>
)SvF
if(num < 1) `^afbW
num = 1; f.'o4HSj
this.num = num; zYj8\iER
} A0WQZt!FEN
`)H.TMI
/** Z!|nc.
* 获得总页数 )r1Z}X(#d
*/ mrd(\&EhA
publicint getPageNum(){ Ef$xum{
return(count - 1) / num + 1; .'7o,)pJ<
} JCaT^KLz
o,Ew7~u
/** +V7*vlx-
* 获得本页的开始编号,为 (p-1)*num+1 1rE hL
*/ P/Sv^d5=e
publicint getStart(){ Mk[_yqoCO
return(p - 1) * num + 1; *+qXXCA
} vC J
FQ(=Fnqn
/** Yq)
wE|k/
* @return Returns the results. v=SC*
*/ <h7C_^L10\
publicList<E> getResults(){ )X| uOg&|
return results; 4U>
} "W:'cIw
>48zRi\N
public void setResults(List<E> results){ Fv5@-&y$W
this.results = results; Ty#L%k}-t
} t91v%L
N9:xtrJ]_J
public String toString(){ v D}y%}
StringBuilder buff = new StringBuilder b\VY)=U
+l&ZN\@0X
(); ]eP&r?B
buff.append("{"); 4(
^Ht
buff.append("count:").append(count); bv$)^
buff.append(",p:").append(p); )0RH"#,2L
buff.append(",nump:").append(num); 01#a
buff.append(",results:").append {Sd{|R_
t~ Q{\!
(results); Eh0R0;l5>
buff.append("}"); Y R#_<o
return buff.toString(); g;eMsoJG
} + lU:I
WQ =C5^u
} ~ N_\V
|ay W _5}
<q%buyQna