Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ma)Y@Uw M
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Sc_#BD.
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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 LE%3..
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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 QCIH1\`jW
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分页支持类: $-H#M]Gq
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java代码: (%=[J/F/
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package com.javaeye.common.util; 0"]N9N;/
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import java.util.List; M >#kfSF+
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publicclass PaginationSupport { pJ!:mt
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; Ea#wtow|-
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privateList items; 2{:bv~*I0F
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privateint totalCount; %;$zR}
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privateint[] indexes = newint[0]; ;L (dmx?
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privateint startIndex = 0; lcR53X
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public PaginationSupport(List items, int = s^KZV
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totalCount){ tfW*(oU
setPageSize(PAGESIZE); Loo48
setTotalCount(totalCount); c `C
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setItems(items); >|Ps23J#
setStartIndex(0); 7<;87t]]
} <RH2G
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public PaginationSupport(List items, int <pJeiMo
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totalCount, int startIndex){ jI:5[. Y
setPageSize(PAGESIZE); C\#E1\d
setTotalCount(totalCount); uf4C+ci
setItems(items); 32j@6!
setStartIndex(startIndex); s @\UZC
} 0h ^&`H:
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public PaginationSupport(List items, int ?Ho~6q8O@
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totalCount, int pageSize, int startIndex){ Qz6Ry\u
setPageSize(pageSize); qXC>DGy
setTotalCount(totalCount); &}%rZU
setItems(items); iv@ey-,<
setStartIndex(startIndex); OtK=UtVI
} >(nb8T|
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publicList getItems(){ ], Xva`"
return items; 7J?`gl&C
} }@JPvIE
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publicvoid setItems(List items){ v53qpqc
this.items = items; Ovu!G
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} [AgS@^"sf5
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publicint getPageSize(){ rik-C7
return pageSize; zE$KU$
} AY3nQH
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publicvoid setPageSize(int pageSize){ Xi vzhI4
this.pageSize = pageSize; 3zi(|B[,?
} 1C)
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publicint getTotalCount(){ 2rK%fV53b
return totalCount; HAa$pGb
} ]3UEju8$
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publicvoid setTotalCount(int totalCount){ !58j xh
if(totalCount > 0){ q=Cc2|Ve
this.totalCount = totalCount; ~@g7b`t=la
int count = totalCount / gG5@ KD6k
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pageSize; ,|RS]I>X
if(totalCount % pageSize > 0) )y8 u+5^
count++; 8)n799<.
indexes = newint[count]; !e+ex"7
for(int i = 0; i < count; i++){ v 809/c*
indexes = pageSize * :f1Q0klwP
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} dG5p`N%
}else{ t\&u
this.totalCount = 0; q0* e1QL
} YXeL7W
} qo,uOi
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publicint[] getIndexes(){ #9=as Y
return indexes; NFDh!HUm
} RE*;_DF
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publicvoid setIndexes(int[] indexes){ /F/zMZGSA{
this.indexes = indexes; 8 cN[t.S
} QPL6cU$&R
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publicint getStartIndex(){ .&|Ivz6
return startIndex; s+9q`k^
} A}./ ;[
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publicvoid setStartIndex(int startIndex){ Atdr|2
if(totalCount <= 0)
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this.startIndex = 0; &35 6
elseif(startIndex >= totalCount) f8Z[prfP
this.startIndex = indexes 5X8GR5P
}cl~Vo-mp
[indexes.length - 1]; UJhmhI
elseif(startIndex < 0) vUlGE
this.startIndex = 0; k`#OXLR
else{ B;k3YOg
this.startIndex = indexes uL.)+E
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[startIndex / pageSize]; n2e#rn
} O7]p `Xi8
} ~Bw)rf,
% 3"xn!'vf
publicint getNextIndex(){ g>L4N.ZH_v
int nextIndex = getStartIndex() + 25:[VH$:4
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pageSize; H>zX8qP+
if(nextIndex >= totalCount) U-b(
return getStartIndex(); tWT,U[
else r4X0.
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return nextIndex; 7yUtG^'b
} 4Lg!54P8
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publicint getPreviousIndex(){ pfs'2AFj
int previousIndex = getStartIndex() - CrvL[6i
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pageSize; E:_m6
m
if(previousIndex < 0) {c(@u6l28
return0; 6\9
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else :NHP,"
return previousIndex; V8C62X
} =hw&2c
vZ&{
} _S$SL%;\
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抽象业务类 J*!_kg)>J
java代码: Rhfx
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/** ekR/X
* Created on 2005-7-12 \H^A@f
*/ l?f%2:}m
package com.javaeye.common.business; =x &"aF1
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import java.io.Serializable; 4\#b@1]}
import java.util.List; g,k} nkIT
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import org.hibernate.Criteria; I:l/U-b7h
import org.hibernate.HibernateException; 4qYT
import org.hibernate.Session; S;I>W&U
import org.hibernate.criterion.DetachedCriteria; r;7&U<j~Z
import org.hibernate.criterion.Projections; Ic<J]+Xq
import KUE}^/%z
MsD@pa
org.springframework.orm.hibernate3.HibernateCallback; E! s?amM4
import r@30y/C
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org.springframework.orm.hibernate3.support.HibernateDaoS cns~)j~
pm4'2B|)g
upport; =/Lwprj
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import com.javaeye.common.util.PaginationSupport; \F; S
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public abstract class AbstractManager extends \*
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HibernateDaoSupport { `pJWZ:3
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privateboolean cacheQueries = false; -Uo"!o>x|
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privateString queryCacheRegion; RAs5<US:
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publicvoid setCacheQueries(boolean !xRboPg
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cacheQueries){ ]nQC
this.cacheQueries = cacheQueries; uO{'eT~
} r.vezsH
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publicvoid setQueryCacheRegion(String },& =r= B
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queryCacheRegion){ qN@-H6D1=
this.queryCacheRegion = D:I6nSoC
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queryCacheRegion; TPi=!*$&
} %I^y@2A4`
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publicvoid save(finalObject entity){ Z]\IQDC
getHibernateTemplate().save(entity); ?,AWXiif
} ;p] f5R^
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publicvoid persist(finalObject entity){ .8~zgpK
getHibernateTemplate().save(entity); J.g4I|{
} ]ff5MY 36
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publicvoid update(finalObject entity){ eI:;l];G9
getHibernateTemplate().update(entity); v0uA]6:
} c)Ep<W<r1
x/]]~@:
publicvoid delete(finalObject entity){ w.9'TR
getHibernateTemplate().delete(entity); slRD /
} >ZjGs8&
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publicObject load(finalClass entity, lr-:o@q{
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finalSerializable id){ nLjc.Z\Bl
return getHibernateTemplate().load l99{ eD
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(entity, id); ADW>
} Au[H!J
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publicObject get(finalClass entity, zSM;N^X 8?
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finalSerializable id){ `xm4?6
return getHibernateTemplate().get se, 0Rvkt
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(entity, id); 4&a,7uVer
} -)dS`hM
?=^M(TA;
publicList findAll(finalClass entity){ %yJ
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return getHibernateTemplate().find("from UW@BAj@^@
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" + entity.getName()); X GhV?
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} %@4/W N
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publicList findByNamedQuery(finalString RbA.%~jjx*
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namedQuery){ SWZA`JVK
return getHibernateTemplate wNt-mgir-Q
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().findByNamedQuery(namedQuery); hJIF!eoI
} #Emz9qTsce
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publicList findByNamedQuery(finalString query, I'$}n$UvZ
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finalObject parameter){ `*to(
)
return getHibernateTemplate 7x ?2((
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().findByNamedQuery(query, parameter); <z+b88D
} !?%'Fy6t
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publicList findByNamedQuery(finalString query, 1E'/! |
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finalObject[] parameters){ 60`4
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return getHibernateTemplate 2-#:Y
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().findByNamedQuery(query, parameters); Er]lObfQo
} }G50?"^u
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publicList find(finalString query){ y!;PBsU%Sx
return getHibernateTemplate().find ~BJ~]~0P`
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(query); YKZk/m&H
} @uaf&my,P
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publicList find(finalString query, finalObject =e>#oPH
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parameter){ 14,Pf`5Sz
return getHibernateTemplate().find S5$sB{\R
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(query, parameter); >.]'N:5
} {g7[3WRy
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public PaginationSupport findPageByCriteria xO<$xx
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(final DetachedCriteria detachedCriteria){ W6>SYa
return findPageByCriteria },=0]tvZG#
$)fybnY
(detachedCriteria, PaginationSupport.PAGESIZE, 0); uv,_?x\'
} ydyGPZt
ctzaqsr
public PaginationSupport findPageByCriteria O!c b-
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(final DetachedCriteria detachedCriteria, finalint ?<#2raH-
Rt{`v<
startIndex){ BIr24N
return findPageByCriteria XazKS4(
p`i_s(u
(detachedCriteria, PaginationSupport.PAGESIZE, kK]^q|vb6
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startIndex); P=j89-e
} :Gdfpz-{?
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public PaginationSupport findPageByCriteria !QB(M@1
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(final DetachedCriteria detachedCriteria, finalint mu1Lg s$;
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pageSize, 0uf'6<f R
finalint startIndex){ =7Wr
return(PaginationSupport) "^~>aVuXf
$6c8<!B_
getHibernateTemplate().execute(new HibernateCallback(){ aFj)s?$4]K
publicObject doInHibernate H9^DlIv('
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(Session session)throws HibernateException { f8DF>]WW
Criteria criteria = -cjwa-9
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detachedCriteria.getExecutableCriteria(session); r#K;@wu2
int totalCount = zLs[vg.(
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t\
((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); jZm57{C#*?
criteria.setProjection l+>&-lX'
*Q<%(JJ
(null); 0ang^v;q
List items = ?\QEK
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criteria.setFirstResult(startIndex).setMaxResults O^D$ ~
]
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(pageSize).list(); QPi]5z?
PaginationSupport ps = ?s<'3I{F`
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new PaginationSupport(items, totalCount, pageSize, aqjS 5!qh
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startIndex); rKDMIECrm
return ps; kpM5/=f/@
} ;P-xKRU!Xx
}, true); 5N:THvh6o
} EV:y}
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public List findAllByCriteria(final wn'_;0fg
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DetachedCriteria detachedCriteria){ ^AWM/aY
return(List) getHibernateTemplate v'C`;I
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().execute(new HibernateCallback(){ ^/Id!Y7
publicObject doInHibernate QD0upYG
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(Session session)throws HibernateException { _5^p+
Criteria criteria = P`'Nv
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detachedCriteria.getExecutableCriteria(session); .1u"16_
return criteria.list(); _LV;q! /j
} &~+lXNXF
}, true); %f.(^<Gu
} R qS2Qo]
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public int getCountByCriteria(final A f@IsCOJ
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DetachedCriteria detachedCriteria){ Gw6*0&3')
Integer count = (Integer) .y {qsL^P
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getHibernateTemplate().execute(new HibernateCallback(){ t)74(
publicObject doInHibernate 8>Hnv]p
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(Session session)throws HibernateException { (5%OAjW
Criteria criteria = BzL>,um
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detachedCriteria.getExecutableCriteria(session); e,qc7BJzK
return |1G /J[E
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criteria.setProjection(Projections.rowCount jb8v3L
0+b1R}!2
()).uniqueResult(); IZczHHEL`b
} ir<HC 'D[
}, true); RYDV60*O6
return count.intValue();
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} ajuwP1I
} h
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用户在web层构造查询条件detachedCriteria,和可选的 r{.DRbn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <;:M:{RZY
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PaginationSupport的实例ps。 T_O\L[]p*
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ps.getItems()得到已分页好的结果集 *Z=K9y,IC
ps.getIndexes()得到分页索引的数组 U@dztX@u
ps.getTotalCount()得到总结果数 pS
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ps.getStartIndex()当前分页索引 s8.O L_e
ps.getNextIndex()下一页索引 (Vglcj
ps.getPreviousIndex()上一页索引 PA;RUe
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8'?V5.6?|~
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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 S/& _
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一下代码重构了。 2`/JT
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我把原本我的做法也提供出来供大家讨论吧: oqHI`Tu
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首先,为了实现分页查询,我封装了一个Page类: n.p6+^ES
java代码: &bBK#d*-u?
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/*Created on 2005-4-14*/ &=5
package org.flyware.util.page; T1c2J,+}R
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/** 4(Gs$QkSo|
* @author Joa T (]
* S',i
*/ pzmm cjEC
publicclass Page { DesvnV'{`
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/** imply if the page has previous page */ 5fPYtVm
privateboolean hasPrePage; fg"@qE-;
@kC>+4s!
/** imply if the page has next page */ nw[DI%Tp
privateboolean hasNextPage; K-F@OSK'
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/** the number of every page */ `W< 7.
privateint everyPage; saQA:W;
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/** the total page number */ 1XQJ#J1/
privateint totalPage; Oi +(`
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/** the number of current page */ >HO{gaRM
privateint currentPage; (qT_4b~
@54, I
/** the begin index of the records by the current j|!.K|9B
[?VYxX@
query */ jca7Cx`sm
privateint beginIndex; 68?oV)fE
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/** The default constructor */ b{qeu$G R
public Page(){ zq-"jpZG
JViglO1\
} xevG)m
e_s9E{(
/** construct the page by everyPage A,D67G<v`
* @param everyPage 'bp*hqG[
* */ 5\1Z"?
public Page(int everyPage){ 8$a4[s
this.everyPage = everyPage; gv$6\1
} 9{@ #tx
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/** The whole constructor */ G%~=hEK0
public Page(boolean hasPrePage, boolean hasNextPage, 9'F-D
T5_z^7d
+%(iGI{
int everyPage, int totalPage, .b>1u3
int currentPage, int beginIndex){ e&Z}struE
this.hasPrePage = hasPrePage; INSI$tA~
this.hasNextPage = hasNextPage; JG&`l{c9
this.everyPage = everyPage; %
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this.totalPage = totalPage; `C"Slz::
this.currentPage = currentPage;
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this.beginIndex = beginIndex; <y5V],-U
} RP'`\||*
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/** I$0JAy
* @return b9%}<w
* Returns the beginIndex. %98F>wl
*/ m)9N9Ii#)
publicint getBeginIndex(){ 3N6U6.Tqb
return beginIndex; D3Lu]=G
} l=*^FK]L`
4S|! iOY
/** UI|L;5
* @param beginIndex q]q(zUtU
* The beginIndex to set. @<Au|l`
*/ )l*H$8
publicvoid setBeginIndex(int beginIndex){ K[)N/Q
this.beginIndex = beginIndex; cAC2Xq
} Rt~Aud[
vfzGRr
/** ~J!a?]
* @return ,pir,Eozg
* Returns the currentPage. hABC
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*/ {n%-^9b1{&
publicint getCurrentPage(){ d}tn/Eu?B
return currentPage; EAo7(d@
} ~jAOGo/&6
3P Twpq1
/** :xZ/c\
* @param currentPage R[
S*ON
* The currentPage to set. 6,M>' s,N
*/ k6rX/ocu
publicvoid setCurrentPage(int currentPage){ uxk&5RY
this.currentPage = currentPage; 0TU~Q
} Pgf$GXE
>`=
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/** jo=XxA
* @return VuFMjY
* Returns the everyPage. @;_r`AT7
*/ qRsPi0;
publicint getEveryPage(){ N'Va&"&73>
return everyPage; aAO[Y"-:,Y
} |Z6rP-
x(3E#7>1
/** W-=~Afy
* @param everyPage U
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* The everyPage to set. rS/Q
*/ k<=.1cFh
publicvoid setEveryPage(int everyPage){ _Pa(5-S'KR
this.everyPage = everyPage; y%
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} ?PiJ7|
tc@v9`^_
/** ] =b?^'
* @return *r p@`W5
* Returns the hasNextPage. !6|Kpy8
*/ 2f`u?T
publicboolean getHasNextPage(){ 8gJ"7,}-'
return hasNextPage; IkH]W!_+
} `j[)iok
UBpYR>
<\
/** ywmx6q4MFL
* @param hasNextPage 9g>]m6
* The hasNextPage to set.
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*/ ]jG%<j9A
publicvoid setHasNextPage(boolean hasNextPage){ HoymGU`w
this.hasNextPage = hasNextPage; B9iH+
]W
} C5i]n? )S
~zRUJ2hD!
/** z|}Anc[\
* @return )<DL'
* Returns the hasPrePage. c G?RisSZ
*/ "My \&0-
publicboolean getHasPrePage(){ )Be}Ev#)Zx
return hasPrePage; ma~WJ0LM\
} %,a.431gi
#$K\:V+ 4
/** "pdG%$
* @param hasPrePage |GL#E"[&'
* The hasPrePage to set. itX<!
*/ \PU|<Ru.
publicvoid setHasPrePage(boolean hasPrePage){ PLg`\|
this.hasPrePage = hasPrePage; /,2Em>
} fcr\XCG7U
GUmOK=D >
/** Da_g3z
* @return Returns the totalPage. vwZ2kk!|i
*
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*/
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publicint getTotalPage(){ p:k>!8.Qho
return totalPage; SR%h=`t
} "J, ErnM
s4;SA
/** vhTte
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* @param totalPage u` `FD
* The totalPage to set. *<xEM-
*/ uV52ko,
publicvoid setTotalPage(int totalPage){ zvdtP'&uj
this.totalPage = totalPage; ~k+-))pf
} vov"60K
vxZvK0b620
} o{
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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 Ca*^U-
FX+Ra@I!
个PageUtil,负责对Page对象进行构造: v#(wc+[
java代码: G7M:LcX
7zgU>$i
Pd%o6~_*
/*Created on 2005-4-14*/ B<H5WI
package org.flyware.util.page; hCc_+/j|
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import org.apache.commons.logging.Log; Av_1cvR:
import org.apache.commons.logging.LogFactory; xQm!
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/** gK9@-e
* @author Joa x
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2]~-
* km}%7|R?
*/ +K;
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publicclass PageUtil { 3O:Z;YP:<
JyjS#BWi
privatestaticfinal Log logger = LogFactory.getLog bv4lgRE6Y
Z8 1]>
(PageUtil.class); /V2Ih
R8W{[@
/** =Mc*~[D/
* Use the origin page to create a new page bs
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* @param page t1 OnA#]/_
* @param totalRecords aHXd1\6m
* @return p4fU/
*/ <omSK-
T-
publicstatic Page createPage(Page page, int V[(zRGa{
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totalRecords){ W+cmn )8
return createPage(page.getEveryPage(), \{\*h /m
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page.getCurrentPage(), totalRecords); 'Wn'BRXq3
} Z0`Bn5
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/** .Lr;{B
* the basic page utils not including exception 7s4G|N[wR\
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handler 0/6f9A
* @param everyPage [O2xE037h`
* @param currentPage "@xI
* @param totalRecords #e}Q|pF
* @return page Ovxs+mQ
*/ %|*tL7
publicstatic Page createPage(int everyPage, int Kyq/'9`
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currentPage, int totalRecords){ CCNrjaA
everyPage = getEveryPage(everyPage); 2`9e20
currentPage = getCurrentPage(currentPage); bX Q*d_]WT
int beginIndex = getBeginIndex(everyPage, C*a>B,H
M2W4 RovfR
currentPage); `aD~\O
int totalPage = getTotalPage(everyPage, *P7 H=Yf&
UMILAoR
totalRecords); M4w,J2_8MK
boolean hasNextPage = hasNextPage(currentPage, ><V<}&:y$(
uZL,+Ce|
totalPage); LUc!a4i"fO
boolean hasPrePage = hasPrePage(currentPage); v6uR[18
]$oo1ssZ1
returnnew Page(hasPrePage, hasNextPage, pX8TzmIB0
everyPage, totalPage, A=JPmsj.
currentPage, wW
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:
E[\1
beginIndex); :[xFp}w{
} Y&!-VW
Y)H~*-vGu
privatestaticint getEveryPage(int everyPage){ O?L6Ues
return everyPage == 0 ? 10 : everyPage; i=T!4'Zu
} 6|:K1bI)
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privatestaticint getCurrentPage(int currentPage){ tAF#kBa\y_
return currentPage == 0 ? 1 : currentPage; + -~8t^
} ~ES6Qw`Oe
(SGX|,5X7
privatestaticint getBeginIndex(int everyPage, int 2>TOCBB"
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currentPage){ V1di#i:
return(currentPage - 1) * everyPage; tf[)Q:|
} "QSmxr
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privatestaticint getTotalPage(int everyPage, int {6Y |Z>
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totalRecords){ OD[q
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int totalPage = 0; Fi)(~ji:
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if(totalRecords % everyPage == 0) W% @r
totalPage = totalRecords / everyPage; Z<D8{&AjS
else tE'^O<
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totalPage = totalRecords / everyPage + 1 ; O]_a$U*6
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return totalPage; W_.WMbT
} rj}O2~W~4
W {A4*{
privatestaticboolean hasPrePage(int currentPage){ :3b.`s(M
return currentPage == 1 ? false : true;
6a}
} B SH2Kq
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privatestaticboolean hasNextPage(int currentPage, z@I'Ryalyc
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int totalPage){ Oh# z zo
return currentPage == totalPage || totalPage == %(&$CmS@
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0 ? false : true; +>3jMs~&
}
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} ^XX_ qC'1
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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。 .8wf {y
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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 "%}24t%
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做法如下: =kTHfdin&
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 dBw7l}
YdDP;,
DA
的信息,和一个结果集List: +=:_a$98
java代码: {p.^E5&
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/*Created on 2005-6-13*/ A+|bJ>q
package com.adt.bo; /!?b&N/d)
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import java.util.List; Fr~\ZL
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import org.flyware.util.page.Page; oam$9 q
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/** Mw3$QRM
* @author Joa 2?Y8hm
*/ NH;e|8
publicclass Result { 5,-g^o7
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private Page page; denxcDFu/~
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private List content; uwQgu!|x
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/** eR4ib-nS
* The default constructor JH| D
*/ oi
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public Result(){ 2Z(t/Zp>
super(); ny{S&f
} XHxJzYMc
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/** v4Wq0>o
* The constructor using fields ep~+]7\
* B`.aQ
* @param page L pq)TE#
* @param content pV(k6h
*/ qdLzB
public Result(Page page, List content){ je@&|9h
this.page = page; BYu(a
this.content = content; s>:gL,%c
} tmOy"mq67
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/** :-O$rm
* @return Returns the content. u(FOSmNkN
*/ :1Nc6G
publicList getContent(){ ZBR^$?nj
return content; pj<aMh
} Gk+R,:
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/** L){V(*K '
* @return Returns the page. $3B%4#s
*/ pdm(7^
public Page getPage(){ qtdkK LT
return page; vmEn$`&2t
} yZ 7)|j
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/** G62;p#
* @param content g)\ Tex<
* The content to set. x&^Xgi?
*/ :!l.ze{F
public void setContent(List content){ 1) K<x
this.content = content; [u;(4sa}
} y9?*H?f,
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/** t\LE\[XM>
* @param page ovOV&Zt
* The page to set. 7D,nxx(`
*/ ks sRwe%>;
publicvoid setPage(Page page){ @67GVPcxl
this.page = page; q+4dHS)x
} ~CHcbEWk)W
} "9dZ
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2. 编写业务逻辑接口,并实现它(UserManager, :R
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UserManagerImpl) ,aD~7QX1:
java代码: shL_{}
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/*Created on 2005-7-15*/ 5D=U.UdR
package com.adt.service; 6T+y m9
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import net.sf.hibernate.HibernateException; H" A@Q.'
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import org.flyware.util.page.Page; nu:l;+,VY
Z
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import com.adt.bo.Result; IY6Qd4157
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/** %-fS:~$
* @author Joa RTvOaZ
*/ 7)1%Z{Dy
publicinterface UserManager { 2Mq@5n
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public Result listUser(Page page)throws )Ghw!m
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HibernateException; Z_dL@\#|
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} ZU0*iA
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java代码: RTbV!I
b;*'j9ly
9bRUN<
/*Created on 2005-7-15*/ iD%a;]
package com.adt.service.impl; :6%ivS
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import java.util.List; S76MY&Vx23
4Ozcs'}
import net.sf.hibernate.HibernateException; Isvb;VT9L
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import org.flyware.util.page.Page; (RrC<5"
import org.flyware.util.page.PageUtil; lTN^c?
3LJ\y
import com.adt.bo.Result; #H
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import com.adt.dao.UserDAO; ek/zQM@%
import com.adt.exception.ObjectNotFoundException; FYu30
import com.adt.service.UserManager; `-cw[@uD
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/** ?li/mc.XG
* @author Joa )K::WqR%w)
*/ 0t"Iq71/
publicclass UserManagerImpl implements UserManager { [euR<i*I#
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private UserDAO userDAO; b KIL@AI
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/** ,CPAS}kS
* @param userDAO The userDAO to set. ~@QAa (P.
*/ mea}
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publicvoid setUserDAO(UserDAO userDAO){ 5 A5t
this.userDAO = userDAO; /zQx}U)TP
} J{kS4v*J
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/* (non-Javadoc) vr?u=_%Z
* @see com.adt.service.UserManager#listUser l=Jw6F+5
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(org.flyware.util.page.Page) 7B5b
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*/ V!yBH<X
public Result listUser(Page page)throws y0?HZ Xq
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HibernateException, ObjectNotFoundException { {%P2.:
int totalRecords = userDAO.getUserCount(); Fo%`X[ ?
if(totalRecords == 0) @;y@Hf'Jv
throw new ObjectNotFoundException *<[\|L:#]Z
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("userNotExist"); -k2|`t _
page = PageUtil.createPage(page, totalRecords); L\bcR
List users = userDAO.getUserByPage(page); 9H:J&'Xi7
returnnew Result(page, users); :f_oN3F p
} luac
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} Bf+~&I#E
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OUO'w6m!
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询,接下来编写UserDAO的代码: Vj8-[ww!
3. UserDAO 和 UserDAOImpl: U#w0 E G
java代码: iYw1{U
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/*Created on 2005-7-15*/ Nr)DU.f
package com.adt.dao; MU `!sb*
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import java.util.List; {,T=Siy
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import org.flyware.util.page.Page; 2S[:mnK
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import net.sf.hibernate.HibernateException; M)wNu
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/** @ <4 U &
* @author Joa ;<+Z}d/g9
*/ i=rA;2>
publicinterface UserDAO extends BaseDAO { H+gB|
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publicList getUserByName(String name)throws *&h]PhY
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HibernateException; R{aqn0M
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publicint getUserCount()throws HibernateException; a?Y> hvI
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publicList getUserByPage(Page page)throws ]y$/~(OW
q%]5/.J
HibernateException; #KHj.Vg
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} f/0k,~,*
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java代码: od,,2pwK+
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/*Created on 2005-7-15*/ :r:x|[3.
package com.adt.dao.impl; PBL=P+
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import java.util.List; F<*zL:-Z
c%
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import org.flyware.util.page.Page; cb. -AlqQ
%_>8.7
import net.sf.hibernate.HibernateException; 4JH^R^O<n
import net.sf.hibernate.Query; k@>(sXs
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import com.adt.dao.UserDAO; NKVLd_f k
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/** HA&hu/mw_
* @author Joa &=In
*/ UZ:z|a3
public class UserDAOImpl extends BaseDAOHibernateImpl jF#Dc[*
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implements UserDAO { ;1r|Bx <5
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/* (non-Javadoc) &$~irI
* @see com.adt.dao.UserDAO#getUserByName :/>Zky8,k
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(java.lang.String) DW)81*~g
*/ @FRas00)|
publicList getUserByName(String name)throws \r3SvBwhFv
8\?H`NN
HibernateException { _@_EQ!=
String querySentence = "FROM user in class sv6m)pwh
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com.adt.po.User WHERE user.name=:name"; S.U#lAn(
Query query = getSession().createQuery +7y#c20
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(querySentence); O6\c1ha
query.setParameter("name", name); =W gzj|Kr
return query.list(); +Je%8jH
} VwLo
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/* (non-Javadoc) L3*HgkQQ
* @see com.adt.dao.UserDAO#getUserCount() pMf
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*/ aZq7(pen
publicint getUserCount()throws HibernateException { y7Hoy.(
int count = 0; Xhpcu1nA
String querySentence = "SELECT count(*) FROM IGA4"\s
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user in class com.adt.po.User"; #w!ewC vt
Query query = getSession().createQuery 'sa>G
{s:"mkR
(querySentence); NBw{
count = ((Integer)query.iterate().next Jpn= ^f[rm
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()).intValue(); 79+i4(H
return count; >H,E3Z
} H=mFc@fh
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/* (non-Javadoc) UC.kI&A
* @see com.adt.dao.UserDAO#getUserByPage MIqH%W.ru
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(org.flyware.util.page.Page) UsdMCJ&G
*/ $3cZS
publicList getUserByPage(Page page)throws Io{BO.K*Y
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HibernateException { :OA;vp~$x
String querySentence = "FROM user in class Us%g&MWdpb
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com.adt.po.User"; /RWD\u<l
Query query = getSession().createQuery Qve5qJ
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(querySentence); ^,`]Q)P^
query.setFirstResult(page.getBeginIndex()) G[{Av5g mx
.setMaxResults(page.getEveryPage()); vTC{
return query.list(); ~m[Gp;pL
} J.]`l\
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} LyG`q3@
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w zi7pJjXh
$"?$r
至此,一个完整的分页程序完成。前台的只需要调用
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#8y"1I=i&
userManager.listUser(page)即可得到一个Page对象和结果集对象 (B03f$8}*_
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的综合体,而传入的参数page对象则可以由前台传入,如果用 3Z7gPU!H=
xE!b) @>S
webwork,甚至可以直接在配置文件中指定。 }nSu7)3$B
{`(MK6D8 c
下面给出一个webwork调用示例: Z/ L%?zH
java代码: 'lOQb)
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/*Created on 2005-6-17*/ lwIxn1n
package com.adt.action.user; N0N%~3
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import java.util.List; ,bP8"|e
a %?v/Ku
import org.apache.commons.logging.Log; e*d lGK3l
import org.apache.commons.logging.LogFactory; LLbI}:
import org.flyware.util.page.Page; Bj\Us$cZ
?a'EkZ.dB
import com.adt.bo.Result; 12: Q`
import com.adt.service.UserService; </R@)_'
import com.opensymphony.xwork.Action; }9FWtXAU^1
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/**
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* @author Joa Q5_ ,`r`
*/ 6rO^ p
publicclass ListUser implementsAction{ =5uhIU0O
jc@=
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privatestaticfinal Log logger = LogFactory.getLog I*/:rb
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(ListUser.class); 735l&(3A\
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private UserService userService; n8D'fvY
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private Page page; [jEA|rd~}
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privateList users; =`Ky N/
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/* x@:98P
* (non-Javadoc) kV3LFPf>0
* ?}EWfsA
* @see com.opensymphony.xwork.Action#execute() yA7O<p+
*/ )QmmI[,tq
publicString execute()throwsException{ Bgai|l
Result result = userService.listUser(page); z`D|O|#q
page = result.getPage(); +aqQa~}r
users = result.getContent(); 0
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return SUCCESS; !#E-p?O.
} v[?gM.SF
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/** C[;7i!Dv
* @return Returns the page. f/Z-dM\e
*/ jP<6Q|5F
public Page getPage(){ .mOm@<Xdg
return page; PE[5oH
} aD~S~L!
&]anRT#
/** 'uwq^b_
* @return Returns the users. =YtK@+| i
*/ DYew6B-
publicList getUsers(){ `eGp.[ffT
return users; DnN+W
} ")fgQ3XZ
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/** 77 ?TRC
* @param page P)ne^_
* The page to set. U)z1RHP|z
*/ DG3Mcf@5
publicvoid setPage(Page page){ =E~_F>SD
this.page = page; 2 m72PU<.
} bf\ Uq<&IJ
%,d+jBM
/** &d"scM5
* @param users )F0Q2P1I
* The users to set. TNcMrbWA
*/ ^q<EnsY
publicvoid setUsers(List users){ Zh?n;n}
this.users = users; q z!^<
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} -3XnUGK
LBcqFvj{&
/** x+1-^XvK
* @param userService /]nrxT
* The userService to set. 7 S%`]M4;
*/ Z,F1n/7
publicvoid setUserService(UserService userService){ ^;Yjs.bI`F
this.userService = userService; g
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} " &mwrjn"T
} mNX0BZ
rE\&FVx
>DW%i\k1V~
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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, #Vm)wH3
W'Qy4bl7C
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 wee5Nirw6
y!\q', F
么只需要: 2}ywNVS
java代码: a$Ghb]
&hzr(v~;
<Oj'0NK-
<?xml version="1.0"?> 'gk^NAG2^E
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ITjg]taD
X|60W
1.0//EN" "http://www.opensymphony.com/xwork/xwork- PC)V".W1
yIS&ZtBA
1.0.dtd"> x2g=%K=
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<xwork> Uz7V2r%]
JZD&u6tB
<package name="user" extends="webwork- JWQ.Efe
+#g4Crb
interceptors"> ]tEH `Kl
7L!q{%}
<!-- The default interceptor stack name (m=F
HOVzpj
--> jt&rOPL7
<default-interceptor-ref 1.j;Xo/+:V
`I5So-^&z
name="myDefaultWebStack"/> vslN([@JR
y Xi$w.gr
<action name="listUser" 2iWxx:e
"J3n_3+
class="com.adt.action.user.ListUser"> y~+U(-&.
<param y1Yrf,E
m=
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name="page.everyPage">10</param> G~Fjla\?Q
<result P vS\
&$_#{?dPt
name="success">/user/user_list.jsp</result> `~ R%}ID
</action> :FI4GR*?
xA"7a
</package> n)>nfnh
%ZZW
p%uf
</xwork> irzWk3@:
0'^zIL#.
62J-)~_
GvD{ I;
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}G[Qm2k
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 .tRWL!
8E\6RjM
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。 5TcirVO82
'~kAsn*/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 WiclG8l
Q
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npdpKd+*K"
{t<U:*n2
}\)O1
我写的一个用于分页的类,用了泛型了,hoho Wq]Lb:&