Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `2.2; Vk
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K6nGC
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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 Qz9*o
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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 z-;2)RkV2
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分页支持类: B?p18u$i#l
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java代码: /
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package com.javaeye.common.util; F3pBk)>a\
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import java.util.List; ;!H|0sv
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publicclass PaginationSupport { Cp[
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publicfinalstaticint PAGESIZE = 30; 6|AD]/t^K
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privateint pageSize = PAGESIZE; qt{{q
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privateList items; eV)'@8p
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privateint totalCount; i |IG
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privateint[] indexes = newint[0]; f!n0kXVu6U
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privateint startIndex = 0; (M,IgSn9
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public PaginationSupport(List items, int 6x 8P}?
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totalCount){ E3==gYCe*
setPageSize(PAGESIZE); ~qj09
setTotalCount(totalCount); @.SuHd
setItems(items); TqN4OkCm/
setStartIndex(0); Z<^TO1xs9B
} 67{>x[
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public PaginationSupport(List items, int !Ey=
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totalCount, int startIndex){ 32KL~32Y
setPageSize(PAGESIZE); UoSzxL
setTotalCount(totalCount); i9Tq h
setItems(items); W`2Xn?g
setStartIndex(startIndex); Y&JK*d
} n13#}i{tm
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public PaginationSupport(List items, int 1*o=I-nOa
l=.h]]`;
totalCount, int pageSize, int startIndex){ j|/4V
setPageSize(pageSize); a/v!W@Zz}
setTotalCount(totalCount); X:1&Pdi
setItems(items); 5B76D12
setStartIndex(startIndex); C~:@ETcbil
} DtrR< &m
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publicList getItems(){ g!*5@k|C
return items; 7Fd`MTo
} !CO1I-yL
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publicvoid setItems(List items){ ~R!M.gY[rK
this.items = items; y
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} ]#*S. r]
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publicint getPageSize(){ 5gZ6H/.
return pageSize; G&LOjd2
} N(W;\>P
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publicvoid setPageSize(int pageSize){ ~Y.I;EPKt
this.pageSize = pageSize; vz1yH%~E
} j[e<CGZ
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publicint getTotalCount(){ xS>d$)rIj
return totalCount; 2uln)]
} 4,)EG1
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publicvoid setTotalCount(int totalCount){ H/?@UJ5m
if(totalCount > 0){ RL|d-A+;
this.totalCount = totalCount; do$+ Eh
int count = totalCount / v+b#8
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pageSize; R5KOai!
if(totalCount % pageSize > 0) "xK#%eJjWd
count++; N9}27T+4
indexes = newint[count]; 9>I&Z8J$M
for(int i = 0; i < count; i++){ -\dcs?
indexes = pageSize *
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i; Z,Z4Sp
} I)YUGA5
}else{ SE7mn6,%\
this.totalCount = 0; Ua2wa A
} mY1Gm|
} 49?wEm#
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publicint[] getIndexes(){ \)'5V!B|s
return indexes; !+(c/ gwBh
}
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publicvoid setIndexes(int[] indexes){ &`^PO$
this.indexes = indexes; V<&^zIJUR
} L}M%z9K`h
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publicint getStartIndex(){ UrRYK-g
return startIndex; iz-B)^8.
} ~4V-{-=0a7
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publicvoid setStartIndex(int startIndex){ #9e 2+5s
if(totalCount <= 0) [fZhfZ)<
this.startIndex = 0; Xf%vfAf
elseif(startIndex >= totalCount) =_=0l+\}
this.startIndex = indexes P|tNmv[;
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[indexes.length - 1]; 4L _AhX7
elseif(startIndex < 0) "~:P-]`G
this.startIndex = 0; 'Y22HVUX
else{ j^)=<+Q;=
this.startIndex = indexes S[5OTwa8L
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[startIndex / pageSize]; W1
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} HXb^K
} @*&`1
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publicint getNextIndex(){ %{B4M#~
int nextIndex = getStartIndex() + "BA&
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pageSize; SNrX(V::z
if(nextIndex >= totalCount) j*_>/gi
return getStartIndex(); 9|l6.$Me/
else k[a5D/b
return nextIndex; ;-quK%VO!
} 3U9leY'2N
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publicint getPreviousIndex(){ (YY!e2
int previousIndex = getStartIndex() - lGXr-K?+Y
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pageSize; Bp/k{7
if(previousIndex < 0) p>1Klh:8.'
return0; <Q@{6
else gg&Dej2{
return previousIndex; G7k.YtW
} }_fVv{D
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} I3AxKA
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抽象业务类 GiKmB-HO
java代码: :1gcLsF
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/** NC%)SG \
* Created on 2005-7-12 uWkuw5;
*/ rW[7
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package com.javaeye.common.business; ar:qCq$\
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import java.io.Serializable; l TJM}K
import java.util.List; :o_6
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import org.hibernate.Criteria; v;:. k,E0
import org.hibernate.HibernateException; vqRW^>~-B
import org.hibernate.Session; 6D29s]h2
import org.hibernate.criterion.DetachedCriteria; ee*E:Ltz\
import org.hibernate.criterion.Projections; f/pr
import K~14;
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org.springframework.orm.hibernate3.HibernateCallback; Jm3iYR+,
import y2@8?
Ombvp;
org.springframework.orm.hibernate3.support.HibernateDaoS h"(HDn q
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upport; Os)}kkja
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import com.javaeye.common.util.PaginationSupport; a*?,wmzl
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public abstract class AbstractManager extends !po29w:S
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HibernateDaoSupport { cp5
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privateboolean cacheQueries = false; gg QI
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privateString queryCacheRegion; h9j/mUwV
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publicvoid setCacheQueries(boolean z/t+t_y
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cacheQueries){ bS*oFm@u
this.cacheQueries = cacheQueries; /;xmM2B'
} T^.W'
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publicvoid setQueryCacheRegion(String =xPBolxm5U
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queryCacheRegion){ usOIbrQ
this.queryCacheRegion = S<DS|qOo
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queryCacheRegion; v1~`76^
} Oxr?y8C~
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publicvoid save(finalObject entity){ J2Eb"y>/;
getHibernateTemplate().save(entity); Pt8 U0)i)
} 'E~[I"0
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publicvoid persist(finalObject entity){ X5wYfN
getHibernateTemplate().save(entity); Wj#Gm
} 5mF"nY&lI
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publicvoid update(finalObject entity){ AV^Sla7|_
getHibernateTemplate().update(entity); ^n8r mh_%
} NRZ>03w
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publicvoid delete(finalObject entity){ @M ]7',2"
getHibernateTemplate().delete(entity); yf7$m_$C'
} i*Ee(m]I
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publicObject load(finalClass entity, |\S p IFH1
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finalSerializable id){ jwZBWt )5
return getHibernateTemplate().load kc-v(WIC
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(entity, id); nK5FPFz8
} &[4lP~
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publicObject get(finalClass entity, 4O** %!|
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finalSerializable id){ l*z.20^P
return getHibernateTemplate().get >6"u{Qmr
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(entity, id); -P|st;?#
} 6zJfsKf$
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publicList findAll(finalClass entity){ L/n?1'he
return getHibernateTemplate().find("from 2q,> *B?
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" + entity.getName()); Wf>scl`s
} o$_,2$>mn
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publicList findByNamedQuery(finalString ]M5w!O!
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namedQuery){ ?O<D&CvB
return getHibernateTemplate cN\Fgbt
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().findByNamedQuery(namedQuery); QSq0{
} v\:P_J
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publicList findByNamedQuery(finalString query, { |[n>k
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finalObject parameter){ #0;ULZ99aH
return getHibernateTemplate yxz"9PE/P
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().findByNamedQuery(query, parameter); sHQ82uX
} %\2w
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publicList findByNamedQuery(finalString query, I@<\DltPi
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finalObject[] parameters){ .#[==
return getHibernateTemplate uWE
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}L.&@P<
().findByNamedQuery(query, parameters); *c6o#[l
} eAD uk!Iq
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publicList find(finalString query){ 1f zHmD
return getHibernateTemplate().find l4+Bs!i`
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(query); ^N\$oV$
} a{FCg%vD)
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publicList find(finalString query, finalObject CFU'-
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parameter){ 1SGLA"r
return getHibernateTemplate().find x<es1A'u6
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(query, parameter); o6[aP[~F
} |kXx9vGq@
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public PaginationSupport findPageByCriteria 2)zAX"#/
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(final DetachedCriteria detachedCriteria){ FELDz7DYya
return findPageByCriteria 3</gK$f2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ghb Jty`
} J>XMaI})U
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public PaginationSupport findPageByCriteria P@wu k1
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(final DetachedCriteria detachedCriteria, finalint FbWcq_
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startIndex){ ~DYv6-p%
return findPageByCriteria . h7`Q{
Z/f%$~Ch
(detachedCriteria, PaginationSupport.PAGESIZE, <+mYC'p
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startIndex); DZ7<-SFU
} @z-%:J/$
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public PaginationSupport findPageByCriteria t)
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(final DetachedCriteria detachedCriteria, finalint 5SNa~
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pageSize, %qYiE!%&
finalint startIndex){ t3//
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return(PaginationSupport) ;n~-z5)
!|#W,9
getHibernateTemplate().execute(new HibernateCallback(){ ?~p]Ey}~9
publicObject doInHibernate c&GVIrJ
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(Session session)throws HibernateException { fZ5zsm'N
Criteria criteria = 8h%oJ4da
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detachedCriteria.getExecutableCriteria(session); p-Jp/*R5
int totalCount = 9z$fDs}.q
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((Integer) criteria.setProjection(Projections.rowCount [Ep%9(SgA'
D02(6|
()).uniqueResult()).intValue(); G8t9Lx
criteria.setProjection !w;oVPNg
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(null); psFY=^69o
List items = }83a^E9L
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criteria.setFirstResult(startIndex).setMaxResults aJ/}ID
=}D9sT
(pageSize).list(); y2{uEbA
PaginationSupport ps = !jTtMx
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new PaginationSupport(items, totalCount, pageSize, :2zga=)g
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startIndex); h%%ryQQ&<
return ps; J6[V7R[\
} {KGEv%
}, true); tSVWO]<
} [Xyu_I-c
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public List findAllByCriteria(final >_J9D?3S
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DetachedCriteria detachedCriteria){ |8q:sr_
return(List) getHibernateTemplate !*eDT4a
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().execute(new HibernateCallback(){ !7hjA=0
publicObject doInHibernate
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(Session session)throws HibernateException { {U'\2Ge<m
Criteria criteria = $-MVsa9>I
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detachedCriteria.getExecutableCriteria(session); .mbqsb]&Y
return criteria.list(); @u @~gEt
} 9]Fi2M
}, true); 9$?Sts}6&
} D
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public int getCountByCriteria(final ]?6Pt:N2
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DetachedCriteria detachedCriteria){ hGy[L3{
Integer count = (Integer) )! eJW(
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getHibernateTemplate().execute(new HibernateCallback(){ X`6"^
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publicObject doInHibernate 7 'q *(v
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(Session session)throws HibernateException { smUSR4VK
Criteria criteria = /rIyW?& f
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detachedCriteria.getExecutableCriteria(session); sg8[TFX@Z
return OUk"aAo
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criteria.setProjection(Projections.rowCount {vq| 0t\-
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()).uniqueResult();
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} o (k{Ed
}, true); _a#k3r
return count.intValue(); j'k
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} DL*vF>v
} E<l/o5<nC
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.* )e24`
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用户在web层构造查询条件detachedCriteria,和可选的 uGv|!UQw
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 FUarI5#fwF
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PaginationSupport的实例ps。 :h(`eC
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ps.getItems()得到已分页好的结果集 \_ V*Cs
ps.getIndexes()得到分页索引的数组 Gl@{y (
ps.getTotalCount()得到总结果数 aeISb83Y |
ps.getStartIndex()当前分页索引 * bd3^mP
ps.getNextIndex()下一页索引 Z}TLk^_[
ps.getPreviousIndex()上一页索引 F"bz<{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (6.uNLr
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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 {l)$9!
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一下代码重构了。 .L+XV y
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我把原本我的做法也提供出来供大家讨论吧: ,sIC=V +
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首先,为了实现分页查询,我封装了一个Page类: (-g*U#
java代码: =#/Kg_RKL
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/*Created on 2005-4-14*/ K8aqC{
package org.flyware.util.page; ":_II[FPY
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/** R!%nzL@e&`
* @author Joa a3>/B$pE
* PR
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*/ `XhH{*Q"X
publicclass Page { !uQT4<g
t&xoi7!$
/** imply if the page has previous page */ >Jmla~A
privateboolean hasPrePage; &yvvea]
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/** imply if the page has next page */ iCPm7AU
privateboolean hasNextPage; Wk<fNHg
0k5-S~_\
/** the number of every page */ '< U&8?S
privateint everyPage; -B H/)$-$
;NR|Hi]
/** the total page number */ A<ds+0
privateint totalPage; uYMn VE"
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/** the number of current page */ :YI5O/gsk?
privateint currentPage; =3.dgtH
-;7xUNQ
/** the begin index of the records by the current "_q~S$i^
Sv T0%2
query */ 1o`1W4Q
privateint beginIndex; E ?Mgbd3
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/** The default constructor */ n.&7lg^X
public Page(){ SO=gG 2E
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} 2n,z`(=
&{V |%u}v
/** construct the page by everyPage gS5REC4I/
* @param everyPage !?nO0Ao-$
* */ vN'+5*Cgy6
public Page(int everyPage){ !fzS' pkk.
this.everyPage = everyPage; !+%gJiu:
} [UA*We 1
,*J@ic7"
/** The whole constructor */ s/tLY/U/
public Page(boolean hasPrePage, boolean hasNextPage, XgC^-A w
f6%k;R.Wz
9j:]<?D,A
int everyPage, int totalPage, kk /#&b2
int currentPage, int beginIndex){ ENuL!H>;*
this.hasPrePage = hasPrePage; C2}y#A I
this.hasNextPage = hasNextPage; v>]g="5}8
this.everyPage = everyPage; @G"nkB
this.totalPage = totalPage; QN#"c
this.currentPage = currentPage; bzFac5n)Q
this.beginIndex = beginIndex; _y~6b{T
} L5bq\
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/** FJc8g6M
* @return 7|5kak>=
* Returns the beginIndex. @3.Z>KONx
*/ uge r:cD
publicint getBeginIndex(){ 9\4x<*
return beginIndex; AioW*`[WjA
} Wx:v~/r
I=kqkuW
/** O>' }q/
* @param beginIndex 1
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* The beginIndex to set. &<N8d(
*/ KnkmGy
publicvoid setBeginIndex(int beginIndex){ ^Kz?SO
this.beginIndex = beginIndex; I?'*vAW<
} 8\rca:cF
p(n0(}eVC'
/** ~6f/jCluR%
* @return G'\[dwD,u
* Returns the currentPage. yv4x.cfI2W
*/ \6|y~5Hw{r
publicint getCurrentPage(){ 1eD#-tzV
return currentPage; pTCD1)
} K=N&kda
dHDtY$/_
/** 3gUY13C}:p
* @param currentPage .b,\.0N
* The currentPage to set. 2 nyK'k
*/ G<?RH"RZr
publicvoid setCurrentPage(int currentPage){ peVY2\1>R
this.currentPage = currentPage; cg8/v:B
} @rYZ0`E9
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/** LO_Xrj
* @return VeWh9:"bJ
* Returns the everyPage. *:CTIV5N0
*/ !igPyhi,hl
publicint getEveryPage(){ @&m [w'tn
return everyPage; NPH(v`
} FEk9a^Xyx
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/** X%YZQc9
* @param everyPage CH4Nz'X2
* The everyPage to set. 6>WkisxG
*/ !
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publicvoid setEveryPage(int everyPage){ b$'%)\('g
this.everyPage = everyPage; 5;XC!Gz
} %$&eC
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/** >V^8<^?G
* @return R|RGoGE6g
* Returns the hasNextPage. MGF!ZZ\
*/ JP Dxzp
publicboolean getHasNextPage(){ lf(+]k30
return hasNextPage; wrkw,H
} P'Y(f!%
u0wu\
/** j
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* @param hasNextPage 1|p\rHGd
* The hasNextPage to set. <sC(a7i1
*/ fQ 9af)d
publicvoid setHasNextPage(boolean hasNextPage){ K>'4^W5d,
this.hasNextPage = hasNextPage; xQZOGq
} %1{S{FB
q?j7bp]
/** e)HFI|>
* @return wf ]Wm
* Returns the hasPrePage. s>DFAu!
*/ \*MZ1Q*x
publicboolean getHasPrePage(){ L"YQji!
return hasPrePage; <W!T+sMQj
} >7WT4l)7!b
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/** .Yk}iHcW.
* @param hasPrePage 4M"'B A<
* The hasPrePage to set. Ue9d0#9
*/ |}77'w :
publicvoid setHasPrePage(boolean hasPrePage){ #sU>L=
this.hasPrePage = hasPrePage; w?D=
} A@3'I ;
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/** ar@,SKU'K
* @return Returns the totalPage. ~[!Tpq5
* MTwzL<@$
*/ b|87=1^m[
publicint getTotalPage(){ 9+(b7L
return totalPage; %{ U (y#
} @^0}w k
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/** F~v0CBcAL
* @param totalPage \/dOv[
* The totalPage to set. p_xJKQS
*/ c*owP
publicvoid setTotalPage(int totalPage){ g#P]72TQ
this.totalPage = totalPage; |+h x2?Nv
} k6 OO\=
&LV'"2ng8
} Z&@P<
\ $TM=Ykj
c
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l )r^|9{
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 0]ai*\,W7~
sfVzVS[
个PageUtil,负责对Page对象进行构造: `_&vvJPn@!
java代码: K
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/*Created on 2005-4-14*/ M\ wCZG
package org.flyware.util.page;
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import org.apache.commons.logging.Log; D{7sfkcJ
import org.apache.commons.logging.LogFactory; Eb,M+c?
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/** [g==#[
* @author Joa = m|<~t
* 2n"-~'3\
*/ dM"5obEb
publicclass PageUtil { Y xnZ0MY
DW,Z})9
privatestaticfinal Log logger = LogFactory.getLog s&%r?
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(PageUtil.class); Yi-,Pb?
{DVMs|5;^
/** 5/hgWG6.t
* Use the origin page to create a new page ga'G)d3oS
* @param page {#=o4~u%;H
* @param totalRecords . Z`xNp
* @return U4"&T,'lTL
*/ )REegFN@
publicstatic Page createPage(Page page, int 55b/giX
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totalRecords){ s4Jy96<
return createPage(page.getEveryPage(), W T @XHwt
4U$M0 =
page.getCurrentPage(), totalRecords); a U<+ `
} h5vetci/
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/** MO1H?Uhx
* the basic page utils not including exception (\'lV8}U
E.B6u, Te
handler A'uubFRL2[
* @param everyPage cr18`xU
* @param currentPage IUWJi\,
* @param totalRecords PE_JO(e;Xm
* @return page n-?zH:]GG{
*/ B0g?!.#23
publicstatic Page createPage(int everyPage, int 2Z9ck|L>
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currentPage, int totalRecords){ HKC&grp
everyPage = getEveryPage(everyPage); Wa!C2nB
currentPage = getCurrentPage(currentPage); `OZiN;*|
int beginIndex = getBeginIndex(everyPage, xNJ*TA[+
nh+h3"-d
currentPage); Ix@nRc'
int totalPage = getTotalPage(everyPage, ~1Ffu x
ZlMS=<hgFx
totalRecords); 6m:$RW
boolean hasNextPage = hasNextPage(currentPage, p`"Ic2xPJ
uowdzJ7
totalPage); x=W5e
^0?
boolean hasPrePage = hasPrePage(currentPage); 1Si$Q
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returnnew Page(hasPrePage, hasNextPage, Yi`DRkp]3
everyPage, totalPage, L8pKVr
currentPage, ihct~y-9W
?5[$d{ Gjl
beginIndex); !6 kn>447Y
} &`g^b^i
H-%
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privatestaticint getEveryPage(int everyPage){ v# fny
return everyPage == 0 ? 10 : everyPage; _GoFwVO
} T0o0_R
r0<zy_d'
privatestaticint getCurrentPage(int currentPage){ LCSJIt
return currentPage == 0 ? 1 : currentPage; uesIkJ^Q[
} j3R}]F'C*
f?QP(+M5.
privatestaticint getBeginIndex(int everyPage, int Rx@0EPV
7a4Z~r27/
currentPage){ qnU`Q{
return(currentPage - 1) * everyPage; .|:R#VW
} Gfepm$*%
U*BI/wZ
privatestaticint getTotalPage(int everyPage, int 2%-/}'G*
/RF&@NJE5
totalRecords){ F:Yp1Wrb <
int totalPage = 0; 4^^=^c
jU{~3Gn?
if(totalRecords % everyPage == 0) 94lz?-j
totalPage = totalRecords / everyPage; ~'Korxa
else US<l4
totalPage = totalRecords / everyPage + 1 ; _Q*,~ z~
OL.{lKJ3DV
return totalPage; cVaGgP}\
} 0c&DSL}6
Gl4f:`
privatestaticboolean hasPrePage(int currentPage){ ~kI$8oAry
return currentPage == 1 ? false : true; K;R!>p}t
} YCG$GD
TOx@Y$_9Q8
privatestaticboolean hasNextPage(int currentPage, 0<Rq
Q^'xVS_.
int totalPage){ ^ b{~]I
return currentPage == totalPage || totalPage == >=Na, D
Ibv`/8xh
0 ? false : true; p3IhK>
} )|&FBz;
k7nke^,|
dFk$rr>q
} #_'^oGz`
h\|T(597.
>4?735f=x
6"2IV
8&y#LeM1TT
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。 W#L/|K!S
T9YrB
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 s[t?At->
rL/H{.@$`
做法如下: `Js"*[z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1Uc/r>u9
C)&BtiUN/
的信息,和一个结果集List: =]L ALw
java代码: eB<R"Yvi
EuKkIr/(
=BO>Bi&&
/*Created on 2005-6-13*/ C:vVFU|4
package com.adt.bo; |cl*wFm|3
lG`%4}1
import java.util.List; .6pVt_f0/
V+$fh2t
import org.flyware.util.page.Page; ._6Q "JAB
nCLEAe$W\=
/** =AX"'q
* @author Joa j^m pkv<P
*/ H6MG5f_
publicclass Result { &Y2Dft_K
"BC;zH:
private Page page; :d|~k
3
5p)e c
private List content; R-Gg= l5
:;w#l"e7<
/** Eu[/* t+l
* The default constructor Eg_ram`\R
*/ a6 "-,Kg
public Result(){ $v1_M1
super(); H
;)B5C
} 0\wW%3C
ZtX
CPA!
/** KAnq8B!h
* The constructor using fields (JT
273
* Pk`3sfz
* @param page CTQJ=R"
* @param content ~L"?C
*/
=tc!"{
public Result(Page page, List content){ )<
p
~
this.page = page; xks Me
this.content = content; 2k^'}7G%
} |Zdl[|kX
}qBmt>#
/** 5Rae?*XH
* @return Returns the content. yVyh\u\
*/ "Ve9\$_s
publicList getContent(){ $-paYQ4
return content; a[E}o<{
} 1/J6<FVq
j7J'd?l
/** nPUD6<bF
* @return Returns the page. #cqI0ny?G
*/ I
MG^L
public Page getPage(){ NJg )S2]7
return page; 4-oaq'//BT
} x!n8Wx
)Cd.1X8
/** ur[^/lxx0
* @param content $#E!/vVwD7
* The content to set. N{uVh;_
*/ plM:7#eA
public void setContent(List content){ ,OFNV|S$
this.content = content; yV*4|EkvW
} m"wP]OQH*+
^p3W}D
/** ]#vi/6\J
* @param page sEi9<$~R@0
* The page to set. b8glZb*$
*/ gKtgW&PYm
publicvoid setPage(Page page){ =X7_!vSv
this.page = page; $ByP 9=|
} a`>H69(bU
} #gXxBM
iWIq~t*,H]
/|isRh|
\J(kM,ZJ
9T0g%&
2. 编写业务逻辑接口,并实现它(UserManager, `yO'-(@"gY
BO.Db``
UserManagerImpl) q`UaJ_7
java代码: 0e1-ZP CDj
~EU\\;1Rmq
WWATG=
/*Created on 2005-7-15*/ #\\|:`YV
package com.adt.service; L[!||5y
.AZwVP<
import net.sf.hibernate.HibernateException; gj
I>tz}
)W&{OMr
import org.flyware.util.page.Page; W:K '2j
PlCj<b1D:
import com.adt.bo.Result; gyuBmY
K|I<kA~!H
/** |qBcE
* @author Joa JX{_,2*$
*/ <>)N$$Rx&
publicinterface UserManager { _PSOT5{
',/2J0_
public Result listUser(Page page)throws Y(R.<LtY
$=) Pky-~
HibernateException; {(I":rt#
(%mV,2|:20
}
Z58{YC Y
PbsxjP
n]i#&[*A(
K~B
=}.gU WV
java代码: P>(FCX
;; ;=)'o
n~.$iN
/*Created on 2005-7-15*/ GxEShSGOE
package com.adt.service.impl; wxYGr`f
ZB`d&!W>
import java.util.List; 6@eF|GoP
:>U+HQll
import net.sf.hibernate.HibernateException; E;[Uhh|78!
dT[JVl+3=
import org.flyware.util.page.Page; pTXF^:8
import org.flyware.util.page.PageUtil; A0:rn\$l3
W#=,FZT
import com.adt.bo.Result; W1EYVXN
import com.adt.dao.UserDAO; N1B$z3E*
import com.adt.exception.ObjectNotFoundException; 9Vo*AK'&U
import com.adt.service.UserManager; 8:>V'j
X-#&]^d
/** V1~@
* @author Joa DTSf[zP/
*/ #'0Yzh]qc
publicclass UserManagerImpl implements UserManager { 6q6xqr:W
72 |O&`O
private UserDAO userDAO; e~d=e3mBp
h9/fD5
/** "%p7ft
* @param userDAO The userDAO to set. T^(> 8/O
*/ [:cvy[}v@
publicvoid setUserDAO(UserDAO userDAO){ 9bspf {
this.userDAO = userDAO; 2TNK
} kDI?v6y5
!?=U{^|7y
/* (non-Javadoc) O1bW, n(
* @see com.adt.service.UserManager#listUser ;lvcg)}l
T6QRr}8`/J
(org.flyware.util.page.Page) uxB`
*/ M X8|;t
public Result listUser(Page page)throws @`dlhz
*@H\J e`
HibernateException, ObjectNotFoundException { gKQV99
int totalRecords = userDAO.getUserCount(); W"GW[~
h
if(totalRecords == 0) eLnS1w2
throw new ObjectNotFoundException 1m#.f=u{R
P%gA`j
("userNotExist"); EO~L.E%W
page = PageUtil.createPage(page, totalRecords); kwL|gO1L
List users = userDAO.getUserByPage(page); 7ej u%d
returnnew Result(page, users); >7zC-3
} lo(C3o'
w jD<"p;P
} +`_0tM1
oQObr
O9p s?{g
m\X\Xp~A
J=k=cFUX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 N9-7YQ`D
oLh ,F"nB
询,接下来编写UserDAO的代码: 8-B7_GoJ+B
3. UserDAO 和 UserDAOImpl: ;o9ixmT<-o
java代码: \~"Ub"~I
}\Rmwm-
&9fQW?Czs
/*Created on 2005-7-15*/ ?_i>Kx
package com.adt.dao; V~ORb1
mfN'+`r
import java.util.List; 5af0- hj
brs`R#e \
import org.flyware.util.page.Page; ninWnQq
7HBf^N.
import net.sf.hibernate.HibernateException; zh*D2/r
FK593z
/** f?51sr
* @author Joa 849,1n^
*/ :C(/yg
publicinterface UserDAO extends BaseDAO { #[bL9R5NC
}#7rg_O]>
publicList getUserByName(String name)throws yV )fJ_
fg3Jv*
HibernateException; &UOxS W
DZtpY{=Z
publicint getUserCount()throws HibernateException; >Vjn]V5y
!@F { FR
publicList getUserByPage(Page page)throws f|FS%]fCxk
t4[q:[1
HibernateException; HyVV,q^E
ws+ '*7
} ^`'\eEa
;Pt8\X
/HpM17
+tT"
~x\uZ^:
java代码: ypx~WXFK
W.MZN4=
_huJ*W7lR
/*Created on 2005-7-15*/ wW1VOj=6V"
package com.adt.dao.impl; {zvaZY|K"
m^}|LB:5
import java.util.List; Cl<!S`
P:4"~]}
import org.flyware.util.page.Page; dAx
? ,
i[IFD]Xy!j
import net.sf.hibernate.HibernateException; Lo{wTYt:J
import net.sf.hibernate.Query;
,"(G
)>:~XA|?
import com.adt.dao.UserDAO; A}(]J!rc
pE)NSZ
/** Ee2P]4_d
* @author Joa "u!gfG?oH
*/ dX cbS<
public class UserDAOImpl extends BaseDAOHibernateImpl QQ .?A(U7
\ +%~7Bi]z
implements UserDAO { ~p?ArZb
XNWtX-[^@
/* (non-Javadoc) e^>>"tr
* @see com.adt.dao.UserDAO#getUserByName ['=O>YY
"Zgwe,#
(java.lang.String) EGUlLqP6e
*/ 7,+eG">0
publicList getUserByName(String name)throws x?{UWh%
pqb'L]
HibernateException { Op ar+|p\
String querySentence = "FROM user in class k77 3h`;
KD &nLm!
com.adt.po.User WHERE user.name=:name"; cQ j`W
*
Query query = getSession().createQuery I"88O4\@
Hyy b0c^=
(querySentence); "kyCY9)%
query.setParameter("name", name); ?n`m
return query.list(); ?[Lk]A&"L2
} GpeW<%
\P
hTX[W%K
/* (non-Javadoc) Bdt6 w(`^
* @see com.adt.dao.UserDAO#getUserCount() &L+uu',M0c
*/ Snf_{A<
publicint getUserCount()throws HibernateException { gM3:J:N
int count = 0; pX SShU#
String querySentence = "SELECT count(*) FROM z!"vez
kL*P 3
0
user in class com.adt.po.User"; #uhUZq
Query query = getSession().createQuery 2e1KF=N+
6WY/[TC-
(querySentence); @=Q!a (g
count = ((Integer)query.iterate().next RhE~-b[X
Ik0g(-d
()).intValue(); (?|M'gZ
return count; p"ytt|H
} p0@^1
GEWjQ;g
/* (non-Javadoc) v745FIy<
* @see com.adt.dao.UserDAO#getUserByPage {|?^@
'[{<aEo
(org.flyware.util.page.Page) UucI>E3?P{
*/ X/~uF9a'<
publicList getUserByPage(Page page)throws b"h'7 C/
Jbu2y'zE
HibernateException { bqcCA91
String querySentence = "FROM user in class AEyvljv
]u|fLK.|
com.adt.po.User"; b5NVQ8Mq
Query query = getSession().createQuery 8F}drK9>F
1hG#
(querySentence); z%wh|q
query.setFirstResult(page.getBeginIndex()) |sZqqgZ-
.setMaxResults(page.getEveryPage()); p'K`K\X
return query.list(); jzbq{#
} R@o&c%K"
'o-4'
} ,QcS[9$
.G O0xnm
;o9h|LRs
dht0PZdx?
=u<:'\_
至此,一个完整的分页程序完成。前台的只需要调用 dkC[SG`
cV+?j}"*+
userManager.listUser(page)即可得到一个Page对象和结果集对象 L^sjV/\oW
&jP1Q3
的综合体,而传入的参数page对象则可以由前台传入,如果用 oACAC+CP
Nc:s+ o
webwork,甚至可以直接在配置文件中指定。 bF"l0
jS
``-N2U5
下面给出一个webwork调用示例: L'= \|r
java代码: R=z])
entU+O r
-'&/7e6>y
/*Created on 2005-6-17*/ [;u#79aE
package com.adt.action.user; MR#*/Iw~
za_b jE
import java.util.List; ;+9OzF ;
sK}AS;:
import org.apache.commons.logging.Log; Fv$tl)p*
import org.apache.commons.logging.LogFactory; gQn%RPMh
import org.flyware.util.page.Page; :$WO"HfMSn
'FErk~}/4s
import com.adt.bo.Result; %fj5;}E.
import com.adt.service.UserService; 6cH8Jr _
import com.opensymphony.xwork.Action; ORExI.<`W
}t H$:Z
/** r]3-}:vU
* @author Joa ]@{Lx>Oh"
*/ 9kL,69d2
publicclass ListUser implementsAction{ k#].nQG
.xRdKt!p
privatestaticfinal Log logger = LogFactory.getLog zPby+BP
n|i:4D
(ListUser.class); }Le]qR9Y]
Tuln#<:
private UserService userService;
I1Q!3P
s2<!Zb4
private Page page; 7~7L5PRW
6r)P&J
privateList users; kK? SG3
idI w7hi4
/* /DQYlNa
* (non-Javadoc) -%asHDQ{
* #D`@G8~(
* @see com.opensymphony.xwork.Action#execute() XqTguO'
*/ um2a#6uo
publicString execute()throwsException{ xcB\Y:
Result result = userService.listUser(page); iGyetFqKw
page = result.getPage(); Pe,>ny^J1
users = result.getContent(); \x<8
return SUCCESS; \-\>JPO~<
} /5@YZ?|#2
uFkl^2
/** fLDrit4_Q
* @return Returns the page. $RD~,<oEm
*/ 384n1?
public Page getPage(){ RN$vKJk
return page; f}:C~L!
} j}+3+ 8D
sZ `Tv[
/** QS#@xhH
* @return Returns the users. (,|,j(=]
*/ ":]Xr!e
publicList getUsers(){ xGd60"w2
return users; (v]%kXy/G
} "zEl2Xn28_
'Y?-."eKh
/** X~{6$J|]#i
* @param page WgNA%.|,
* The page to set. oi #B7
*/ s QDgNJbU
publicvoid setPage(Page page){ jPh<VVQ$@
this.page = page; BA;r%?MRL
} wh:;G`6S
"j>X^vn
/** ]N>ZOV,>
* @param users }M07-qIX{
* The users to set.
s*uA3}j
*/ z/7q#~J,
publicvoid setUsers(List users){ 8Pn
this.users = users; 4I4m4^
} ~f<']zXv
nrEI0E9
/** l}nV WuD
* @param userService Iiy5;:CX:q
* The userService to set. >"W^|2R
*/ $AK
^E6
publicvoid setUserService(UserService userService){ G]lGoa}]`u
this.userService = userService; {yn,u)@r9S
} H<Snp)
} Ycr3$n]e
Aztrq
Xaz "!
WjVBz
EC?5GNGT,
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, 9*"
>8Oa(9 n
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 @@Ib^sB%
?2@^O=I
么只需要: 4D65VgVDM
java代码: d`sZ"8}j
?:R ]p2 ID
a;o0#I#Si
<?xml version="1.0"?> cU;Bm}U
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork e@3SF
!j!w$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C[FHqo9M?H
l*ltS(?
1.0.dtd"> yfl?\X{
n_kwtWX(
<xwork> I~7iIUD
W8W7<ml0A
<package name="user" extends="webwork- jg$qp%7i%
^G4YvS(
interceptors"> [6VB&
zs=3e~o3
<!-- The default interceptor stack name k*1Lr\1
,_V V;P
--> rWht},-|1
<default-interceptor-ref Y3 $jNuV
Ip8ml0oG
name="myDefaultWebStack"/> ')xOL=w
w:\} B'u
<action name="listUser" [F<E0rjwM
e-dkvPr
class="com.adt.action.user.ListUser"> .`D'eS6b
<param :8b'HhjM
qT#e
-.G
name="page.everyPage">10</param> !Fl'?Kz
<result O:?3B!wF
^Iw$(
name="success">/user/user_list.jsp</result> cSt)Na~C
</action> '!m6^*m|c
/A9RmTb
</package> v ,")XPY
(3n "a'
</xwork> Yjoe|
t}+/GSwT
Q}#Je.;
ny-:%A
W9SU1{*9
e:O,$R#g
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 }40T'y
+O/b[O'0
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Sa g)}6+
2cCiHEL #
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 #/>TuJc
ImN'o4vo
G9:XEEN
D:T]$<=9
-,8LL@_
我写的一个用于分页的类,用了泛型了,hoho m. pm,
gPd
K%"B@
java代码: fo ~uI(rk
l<6GZ
4!dc/K
package com.intokr.util; d]DV\*v
C8m 9H8Qm
import java.util.List; TIGtX]`
A.>mk598
/** X%yG{\6:
* 用于分页的类<br> UWT%0t_T
* 可以用于传递查询的结果也可以用于传送查询的参数<br> a7g;8t-&
* ovKM;cRs/
* @version 0.01 kX8C'D4 gX
* @author cheng l*l*5hA
*/ Qu|CXUk
public class Paginator<E> { M=iTwK
privateint count = 0; // 总记录数 h%/BZC^L]|
privateint p = 1; // 页编号 ed6@o4D/kf
privateint num = 20; // 每页的记录数 =UKxf
privateList<E> results = null; // 结果 -Q20af-
xO|r<R7d7
/** \V-N~_-H
* 结果总数 jrp>Y:
*/ nXT`7
publicint getCount(){ CXq[VYM&X
return count; Cx TAd[az
} b6-N2F1Fs
P)vD?)Q
publicvoid setCount(int count){ C5~~$7k0
this.count = count; ji ?Hw
} M`Q$-#E:
w5>[hQR\
/** YYQvt
* 本结果所在的页码,从1开始 H~FI@Cf$L
* WZ-~F/:c%
* @return Returns the pageNo. cQEUHhRg!
*/ cC-8.2
publicint getP(){ owIpn=8|Q
return p; Tri\5O0lPs
} @_do<'a
xX&B&"]5
/** PMAz[w,R~
* if(p<=0) p=1 Em!- W5*s
* &'u|^d
* @param p f\2IKpF2
*/ |u>V>
PN
publicvoid setP(int p){ ~uhW~bT
if(p <= 0) BdD]HXB|_
p = 1; 0z/*JVka
this.p = p; Tf3CyH!k
} H@(O{ 9Yl;
p4P=T@:
/** J.UNw8z
* 每页记录数量 5len}){
*/ #&.Znk:@.f
publicint getNum(){ $UzSPhv[
return num; z@`o(gh
} |"}rdOV)
qxI$F
/** ]zYIblpde
* if(num<1) num=1 BvP\c_
*/ =K:[26
publicvoid setNum(int num){ cq[9#@
4=
if(num < 1) ! t!4CY
num = 1; kEh\@x[
this.num = num; 2WS*c7Ct
} uUjjAGZ
0PkX- .
/** _WNbuk0
* 获得总页数 $2W#'_K+
*/ {H/%2
publicint getPageNum(){ pEwo}NS*H
return(count - 1) / num + 1; Mst%]@TG
} DCp8rvUI
O[ z0+Q?6Z
/** K3mP 6Z#2
* 获得本页的开始编号,为 (p-1)*num+1 +2{ f>KZ
*/ -Y524
publicint getStart(){ JLm3qIC
return(p - 1) * num + 1; d*tWFr|J-
} pJFn
8&!J
uzxwJs'fz
/** ,Mw93Kp
Va
* @return Returns the results. 5=V"tQ&d9U
*/ Z=8&`
publicList<E> getResults(){ 4P#jMox
return results; -n7@r
} oO;L l?~
~0,v Q
public void setResults(List<E> results){ #)}BY"C%
this.results = results; _Yo)m|RaB
} K\ Wzh;
@{b5x>KX
public String toString(){ V06*qQ[
StringBuilder buff = new StringBuilder CE
M4E
te[uAJ1 N
(); D`QMlRzXy
buff.append("{"); c9c]1XJ
buff.append("count:").append(count); <U$YJtEK
buff.append(",p:").append(p); 8G)~#;x1
buff.append(",nump:").append(num); ZNH-0mk
buff.append(",results:").append #8XmOJ"W3k
!r.-7hR $
(results); -Y+pLvG*
buff.append("}"); wxBHlgK4z
return buff.toString(); *
4J!@w
} TNh&g.
GTB\95j]
} (su7*$wV
1VYH:uGuAU
_t,aPowX