Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )h 6 w@TF
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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 Zqe$S
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 @J5TDq @
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分页支持类: 1,OkuyXy!>
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java代码: |XG&[TI- "
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package com.javaeye.common.util; G}l9 [lE
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import java.util.List; >jmHe^rH
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publicclass PaginationSupport { Uvc$&j^k
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publicfinalstaticint PAGESIZE = 30; 0',buJncV
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privateint pageSize = PAGESIZE; k\SqDmv
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privateList items; zvq}7,
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privateint totalCount; McS]aJfrk
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privateint[] indexes = newint[0]; rloxM~7!,)
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privateint startIndex = 0; ey9hrRMR
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public PaginationSupport(List items, int D8~\*0->
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totalCount){ k}nGgd6XD
setPageSize(PAGESIZE); 7_j t =sr
setTotalCount(totalCount); *}#HBZe(9
setItems(items); >cmz JS
setStartIndex(0); &XI9%h9|
} c1FSQ
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public PaginationSupport(List items, int b5]<!~Fv:`
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totalCount, int startIndex){ OMo /a%`
setPageSize(PAGESIZE); 90iveb21}
setTotalCount(totalCount); w;Fy/XQ
setItems(items); wX6-WQR
setStartIndex(startIndex); %rrD+
} |unvDXx-
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public PaginationSupport(List items, int H<ovIMd
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totalCount, int pageSize, int startIndex){ dZ*&3.#D5
setPageSize(pageSize); 37?X@@Z=
setTotalCount(totalCount); <v_Wh@m
setItems(items); Lh-Y5(c
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setStartIndex(startIndex); T1Z*>(M
} #"TYk@whWf
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publicList getItems(){ B+R|fQ
return items; l'2vo=IQ
} VE/m|3%t
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publicvoid setItems(List items){ }LX!dDuwA
this.items = items; #fx"tx6
} >Q"3dw
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publicint getPageSize(){ ';.y`{/
return pageSize; yD!GgnW
} ,d.5K*?aI
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publicvoid setPageSize(int pageSize){ ${ DSH
this.pageSize = pageSize; YaQ5Z-c
} +5R8mbD!
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publicint getTotalCount(){ 9|@5eN:N
return totalCount; &E!m(|6?+
} xi,fm
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publicvoid setTotalCount(int totalCount){ Lq6nmjL
if(totalCount > 0){ G'wW-|
this.totalCount = totalCount; ^aJ]|*m
int count = totalCount / :]8A;`G}
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pageSize; OQg}E@LZ
if(totalCount % pageSize > 0) Ho&f[T(
count++; |L}tAS`8
indexes = newint[count]; `@6y Wb:X
for(int i = 0; i < count; i++){ wJgGw5
indexes = pageSize * ^
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} O_
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}else{ `tKs|GQf
this.totalCount = 0; 7g o Rj
} hS%oQ)zvE
} Y~#.otBL&
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publicint[] getIndexes(){ mv$gL
return indexes; L1@<7?@X
} D7B g!*
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publicvoid setIndexes(int[] indexes){ brqmi<*9"[
this.indexes = indexes; (CYQ>)a
} v.,D,6qZ
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publicint getStartIndex(){ 3|URlz
return startIndex; 2j{T8F\]
} RO'b)J:j9
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publicvoid setStartIndex(int startIndex){ 9:E.Iy
if(totalCount <= 0) v//Drj
this.startIndex = 0; g+4x
elseif(startIndex >= totalCount) f/,8sGkX;
this.startIndex = indexes mGw*6kOIS
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[indexes.length - 1]; `w"ooK
elseif(startIndex < 0) h?->A#
this.startIndex = 0; `yRt?UQRS
else{ yOk]RB<'r
this.startIndex = indexes JY D\VaW
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[startIndex / pageSize]; @.QuIm8,
} ]==S?_.B3n
} M=5hp&=
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publicint getNextIndex(){ 0v3
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int nextIndex = getStartIndex() + R:44Gv7
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pageSize; ;T>.
if(nextIndex >= totalCount) ? y[i6yN9
return getStartIndex(); TSRl@QVy
else ~(.&nysZ-
return nextIndex; v dU)
} j>hBNz
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publicint getPreviousIndex(){ #BI Z|
int previousIndex = getStartIndex() - S$GWY^5}{
[](] "r
pageSize; mr XmM<
if(previousIndex < 0) ~8lB#NuN
return0; MeO2 cy!5q
else *adwCiB
return previousIndex; ooN?x31
} e1R<+`]
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} ,GF(pCZzG
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抽象业务类 G,@Jo[e
java代码: zm=|#f
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/** bxAHzOB(\
* Created on 2005-7-12 j=PM]
*/ ]
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package com.javaeye.common.business; Ez Xi*/
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import java.io.Serializable; %u*HNo
import java.util.List; k6|/ ik9C
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import org.hibernate.Criteria; a)rT3gl
import org.hibernate.HibernateException; 8 v<*xy
import org.hibernate.Session; -)!;45
import org.hibernate.criterion.DetachedCriteria; $gaGaB
import org.hibernate.criterion.Projections; `s_k+ g
import rTA#4.*&
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org.springframework.orm.hibernate3.HibernateCallback; M HKnHPv
import %ERR^
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org.springframework.orm.hibernate3.support.HibernateDaoS 6G>loNM^
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upport; x8RiYi+
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import com.javaeye.common.util.PaginationSupport; FLaj|Z~#)
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public abstract class AbstractManager extends _*u$U
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HibernateDaoSupport { n<DZb`/uHZ
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privateboolean cacheQueries = false; r.v.y[u
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privateString queryCacheRegion; !w:pb7+G
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publicvoid setCacheQueries(boolean 2 :&QBwr+;
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cacheQueries){ B8?j"AF
this.cacheQueries = cacheQueries; P+Sgbtc
} ZtX\E+mC
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publicvoid setQueryCacheRegion(String :VlMszy}B3
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queryCacheRegion){ MUMB\K*$
this.queryCacheRegion = "Q;Vy t
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queryCacheRegion; 9oj0X>| 1
} P
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publicvoid save(finalObject entity){ "VA'W/yv!
getHibernateTemplate().save(entity); <(BIWm*
} <E7y:%L[Go
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publicvoid persist(finalObject entity){ ;tfGhHpQn
getHibernateTemplate().save(entity); -z>m]YDH
} nC#SnyUO
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publicvoid update(finalObject entity){ E4xybVo@
getHibernateTemplate().update(entity); MG3xX;
} -
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publicvoid delete(finalObject entity){ oX?~
getHibernateTemplate().delete(entity); z"V`8D
} 68nPz".X
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publicObject load(finalClass entity, 3IQ-2 X--
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finalSerializable id){ k(_^Lq f-
return getHibernateTemplate().load q5>!.v
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(entity, id); ~oeX0l>F
} _>G=xKA#e
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publicObject get(finalClass entity, y1 Y
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finalSerializable id){ #6nuiSF
return getHibernateTemplate().get }*vO&J@z
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(entity, id); !FeNx*31i
} l!%V&HJV
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publicList findAll(finalClass entity){ -@/!u9l
return getHibernateTemplate().find("from r1.OLn?C
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" + entity.getName()); $H1igYc
} n;~6'fxe
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publicList findByNamedQuery(finalString )Z63 cr/
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namedQuery){ 5} 1qo7;
return getHibernateTemplate {EVHkQ+o
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().findByNamedQuery(namedQuery); BDPF>lPf<
} Lq{/r+tt/
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publicList findByNamedQuery(finalString query, %QX"oRMn0
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finalObject parameter){ Z/b,aZhB
return getHibernateTemplate @jD#Tn-*
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().findByNamedQuery(query, parameter); #,rP1#?
} B[[1=
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publicList findByNamedQuery(finalString query, RH&}'4JE:
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finalObject[] parameters){ y?8V'.f|
return getHibernateTemplate KL8WT6!RZ
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().findByNamedQuery(query, parameters); ph@2[rUp
} D0rqte
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publicList find(finalString query){ KPdlg.
return getHibernateTemplate().find q4ej7T8
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(query); eHH9#Vrhc$
} <`*v/D7\02
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publicList find(finalString query, finalObject l
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parameter){ &A~(9IV
return getHibernateTemplate().find E1Rz<&L
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(query, parameter); juBzpQYj
} -/J2;AkGH
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public PaginationSupport findPageByCriteria I}1<epd ,
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(final DetachedCriteria detachedCriteria){ a: [m;
return findPageByCriteria {;?bC'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3G-f+HN^E
} g<N3 L [
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public PaginationSupport findPageByCriteria ? p^ ':@=
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(final DetachedCriteria detachedCriteria, finalint EO\@#",a
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startIndex){ 7\JA8mm
return findPageByCriteria SLI358]$<
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(detachedCriteria, PaginationSupport.PAGESIZE, }J\KnaKo
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startIndex); dG'5: ,n/
} fO$~jxR.
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public PaginationSupport findPageByCriteria Nyo,6 AA
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(final DetachedCriteria detachedCriteria, finalint Wy,Tf*[
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pageSize, OPwO`pN
finalint startIndex){ @X*r5hjc
return(PaginationSupport) "M5&&\uT
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getHibernateTemplate().execute(new HibernateCallback(){ <y5f[HjLy
publicObject doInHibernate xT1{O `
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(Session session)throws HibernateException { #y%?A;
Criteria criteria = za@`,Yq
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detachedCriteria.getExecutableCriteria(session); DV!) n 6
int totalCount = Bn_@R`
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((Integer) criteria.setProjection(Projections.rowCount zSFqy'b.M-
#.n%$r
()).uniqueResult()).intValue(); =!%+ sem
criteria.setProjection -N[Q*;h|
" |l-NUe
(null); kGSB6
List items = ij=}3;L_!
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criteria.setFirstResult(startIndex).setMaxResults
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dv
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(pageSize).list(); P$= Y 5
PaginationSupport ps = cQMb+ Q2Yw
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new PaginationSupport(items, totalCount, pageSize, 4X &\/X
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startIndex); Q+\?gU]
return ps; 0UB,EI8
} 4F+n`{~
}, true); Ysk,9MR(F
} uE6;;Ir#mF
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public List findAllByCriteria(final ?>W4*8(
# N.(ZP
DetachedCriteria detachedCriteria){ ^{T3lQvt
return(List) getHibernateTemplate @{Q[M3l
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().execute(new HibernateCallback(){ dik+BBu5z
publicObject doInHibernate N'nqVYTU
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(Session session)throws HibernateException { lnFOD+y9
Criteria criteria = 0UmK S\P
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detachedCriteria.getExecutableCriteria(session); xPY/J#X$
return criteria.list(); jy] hP?QG
} Xh/i5}5 t
}, true); 3 G?^/nB
} J2`b:%[
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public int getCountByCriteria(final QM1-w^
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DetachedCriteria detachedCriteria){ 6ZBg/_m
Integer count = (Integer) +b.qzgH>r
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getHibernateTemplate().execute(new HibernateCallback(){ oVsj
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publicObject doInHibernate zv]-(<B
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(Session session)throws HibernateException { 6rEt!v #K[
Criteria criteria = R$&|*0
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detachedCriteria.getExecutableCriteria(session); \#[W8k<Z
return I72UkmK`
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criteria.setProjection(Projections.rowCount "-y\F}TE
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()).uniqueResult(); sQ/7Mc
} JbG\Ywi0]
}, true); t@1e9uR
return count.intValue(); ;^:9huN
} N:!XtYA<
} 0}q ij
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用户在web层构造查询条件detachedCriteria,和可选的 Z9ciS";L
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .s|n}{D_i
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PaginationSupport的实例ps。 $nQ; ++
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ps.getItems()得到已分页好的结果集 sMli! u
ps.getIndexes()得到分页索引的数组 M|FwYF^
ps.getTotalCount()得到总结果数 !h7`W*::
ps.getStartIndex()当前分页索引 \~Zj](#
ps.getNextIndex()下一页索引 ;C-5R U
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ps.getPreviousIndex()上一页索引 bslv_OxJ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dW<.
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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 ^o"9f1s 5
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一下代码重构了。 >DQl&:-)t
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我把原本我的做法也提供出来供大家讨论吧: :D-d`OyjG>
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首先,为了实现分页查询,我封装了一个Page类: 'Y6{89 y
java代码: J @"wJEF
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/*Created on 2005-4-14*/ dnNC
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package org.flyware.util.page; ;7 i0ko9
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/** CBs0>M/
* @author Joa }k
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* \Yz>=rY
*/ =]\,I'
publicclass Page { DkA cT[
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/** imply if the page has previous page */ O\XN/R3
privateboolean hasPrePage; HV&N(;@
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/** imply if the page has next page */ kxhvy,t
privateboolean hasNextPage; `HgT5}
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/** the number of every page */ QZ"Lh
privateint everyPage; @;fdf 3ian
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/** the total page number */ #_QvnQ?I
privateint totalPage; @?3u|m |Z
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/** the number of current page */ C:_!zY'z
privateint currentPage; * ?rw'
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/** the begin index of the records by the current EfcoJgX
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query */ 5X|=qZ
privateint beginIndex; /o.wCy,J<
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/** The default constructor */ g>_6O[;t%
public Page(){ `T{{wty
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} 2!-ZNd:(+
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/** construct the page by everyPage zW!3>(L/
* @param everyPage IW
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* */ 1G=1FGvP
public Page(int everyPage){ H-nk\ K<|
this.everyPage = everyPage; ya5;C"
} x5WFPY$wM
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/** The whole constructor */ z(:0@ 5
public Page(boolean hasPrePage, boolean hasNextPage, gvr"F
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int everyPage, int totalPage, .D-} 2<z
int currentPage, int beginIndex){ iJZqAfG{m?
this.hasPrePage = hasPrePage; s!9.o_k
this.hasNextPage = hasNextPage; [ j?n}D@L
this.everyPage = everyPage; y"]?TEd
this.totalPage = totalPage; '8 1M%KO
this.currentPage = currentPage; ]sd|u[:k
this.beginIndex = beginIndex; 0 oEw1!cY
} ]N*q3 y|)
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/** `5r*4N<
* @return - A
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* Returns the beginIndex. |<\o%89AM
*/ ~Hd{+0
publicint getBeginIndex(){ 'aBX>M
return beginIndex; y5kqnibh@
} U)=StpTT
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/** U? [a@Hj{
* @param beginIndex Op" \i
* The beginIndex to set. YjdCCju
*/ I+kGEHO}
publicvoid setBeginIndex(int beginIndex){ 8Focs p2
this.beginIndex = beginIndex; S`8
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} %Nwap~=H;
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/** .5 p"o-:D
* @return gGxgU$`#c
* Returns the currentPage. `J|bGf#
*/ jX-v9eaA
publicint getCurrentPage(){ elG<\[
return currentPage; S;kI\;
} #Q.A)5_
g>12!2}
/** SQDllG84E
* @param currentPage )'?3%$EM
* The currentPage to set. Rb
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*/ [w'Y3U\i
publicvoid setCurrentPage(int currentPage){ ?x7zYE,6
this.currentPage = currentPage; =H%c/Jty
} H5'/i;
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/** 5%,J@&5G s
* @return sMlY!3{Ix
* Returns the everyPage. X`/8fag
*/ /oKa?iT
publicint getEveryPage(){ FloCR=^H
return everyPage; 3jZPv;9OC
} Cp`)*P2
% 3d59O
/** "#\\p~D/<
* @param everyPage vnwS&;-k~
* The everyPage to set. 15U]/?jv8
*/ a'u:1C^\
publicvoid setEveryPage(int everyPage){ lK;|ciq"c7
this.everyPage = everyPage; Xb6X'rY
} L}5nq@Uu)
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/** @xIKYJyU
* @return LI1OocY.]
* Returns the hasNextPage. 21Mr2-#z
*/ .`*h2
publicboolean getHasNextPage(){ 6yH(u}!.
return hasNextPage; gg
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} ^h
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/** fGS5{dti
* @param hasNextPage 'qel3Fs"
* The hasNextPage to set. 7.U
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*/ {WJ9!pA!lk
publicvoid setHasNextPage(boolean hasNextPage){ 3H"bivK
this.hasNextPage = hasNextPage; {[&$W8Li
} K;j}qJvsb
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/** W
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* @return L-SWs8
* Returns the hasPrePage. DvL/xlN
*/ bDK%vx!_
publicboolean getHasPrePage(){ Q|T9tc->
return hasPrePage; N;N,5rxV
} ^}Vx5[
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/** ,Hq*zc c
* @param hasPrePage o}QtKf)W
* The hasPrePage to set. q8 jI
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*/ Ew.a*[W''
publicvoid setHasPrePage(boolean hasPrePage){ e:2e5gz
this.hasPrePage = hasPrePage; Qmbl_#
} |Iq#Q3w
?
}t[
/** ]&;M78^6
* @return Returns the totalPage. tUzef
* gxa@da
*/ "WPFZw:9
publicint getTotalPage(){ %N.qu_,IZ
return totalPage; w&U>w@H^
} Dq$co1eT
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/** h4N%(?7
* @param totalPage #}y(D{z c
* The totalPage to set. Fqr}zR)
*/ Y#[Wv1hi
publicvoid setTotalPage(int totalPage){ bi=IIVlH
this.totalPage = totalPage; F@C^nX9
} `y%1K|Y=
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} gJkvH[hDY
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 zLeId83>
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个PageUtil,负责对Page对象进行构造: B^{87YR
java代码: F~qiNV
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/*Created on 2005-4-14*/ "?[7oI}c&
package org.flyware.util.page; }zK/43Vx
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import org.apache.commons.logging.Log; #!h +K"wX
import org.apache.commons.logging.LogFactory; #c2InwZV
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/** r]0UF0#
* @author Joa nV$ctdusQ
* ":o1g5?
*/ fUJ\W"qya
publicclass PageUtil { pPezy:
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privatestaticfinal Log logger = LogFactory.getLog 4Pm+0=E
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(PageUtil.class); WecJ^{g>r{
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/** tFYIKiq2
* Use the origin page to create a new page <;?&<qMo,P
* @param page N%2UL&w#B
* @param totalRecords wu2AhMGmw
* @return -6()$cl}0
*/
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publicstatic Page createPage(Page page, int V
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totalRecords){ M~G1ZB
return createPage(page.getEveryPage(), F[
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page.getCurrentPage(), totalRecords); ,yC-QFQE
} ^z[-pTY
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/** AlQ!Q)y<@
* the basic page utils not including exception z"eh.&T
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handler 3xW;qNj:!l
* @param everyPage 'z#{'`$a
* @param currentPage SZ9xj^"g
* @param totalRecords RfT#kh/5
* @return page r|Y|uv0
*/ 4LU'E%vlC
publicstatic Page createPage(int everyPage, int Q7y6</4f
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currentPage, int totalRecords){ |wf:|%
everyPage = getEveryPage(everyPage); F_SkS?dB
currentPage = getCurrentPage(currentPage); tPS.r.0#^
int beginIndex = getBeginIndex(everyPage, Q<L.!%vu}
Q#@gOn=W\
currentPage); 6TE RQ
int totalPage = getTotalPage(everyPage, ?l_>rSly5
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totalRecords); pGi "*oZD
boolean hasNextPage = hasNextPage(currentPage, ou44vKzS
Rk
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totalPage); r +]
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boolean hasPrePage = hasPrePage(currentPage); (n-8p6x(
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returnnew Page(hasPrePage, hasNextPage, ?ng?>!
everyPage, totalPage, AWLKve_
currentPage, ,q#^_/?
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beginIndex); `hM:U
} r^P}xGGK
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privatestaticint getEveryPage(int everyPage){ I}Z[F,}*J
return everyPage == 0 ? 10 : everyPage; Y*``C):K%
} oll~|J^sg
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privatestaticint getCurrentPage(int currentPage){
9`^VuC'
return currentPage == 0 ? 1 : currentPage; ewgcpV|spn
} RlX;c!K
@+} Q<
privatestaticint getBeginIndex(int everyPage, int .i/]1X*;r^
i^uC4S~
currentPage){ JRA. ,tQc
return(currentPage - 1) * everyPage; mW 5L;>
} %_1~z[Dv
UhY
)rezh
privatestaticint getTotalPage(int everyPage, int N|Ua|^
ywk;
totalRecords){ $'X*L e@k
int totalPage = 0; hzPx8sO
ok'0Byo
if(totalRecords % everyPage == 0) a-Cp"pKlVY
totalPage = totalRecords / everyPage; @V]
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else c0<Y017sG
totalPage = totalRecords / everyPage + 1 ; ?9!tMRb
/Fh"Gl^
return totalPage; |i?AtOt@f
} N jq#@*>[p
^i-%FY_i5}
privatestaticboolean hasPrePage(int currentPage){ ]rn!+z
return currentPage == 1 ? false : true; w}NgFrL
} FEaf&'G]
2I ?HBz1v
privatestaticboolean hasNextPage(int currentPage, 7!oqn'#>A
:`3b|u=KZ
int totalPage){ +@%9pbM"z
return currentPage == totalPage || totalPage == H
gNUr5p
bq[Q
0 ? false : true; bdaZ{5^{
} ~8pf.^,fi
(P`{0^O"}
`yYgL@Zt
} .[2MPjg
.j}u'!LKul
5\=9&{WjND
,C&h~uRi#f
7=QV ^G
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 6-KC[J^Xo
4#2iL+
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ` V^#Sb
'R]Z9h
做法如下: z(\H.P#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 n+Ag |.,|
g=U?{<8.m
的信息,和一个结果集List: n;Iey[7_E`
java代码: G~B
V^
huKz["]z[
!%s7I^f*
/*Created on 2005-6-13*/ 3gabk/
package com.adt.bo; .k*2T<p$rC
4uftx1o
import java.util.List; c(Ha"tBJ
zi-+@9T
import org.flyware.util.page.Page; rXm!3E6JL
J$EEpL
/** 1MahFeQ[
* @author Joa %BG5[XQ7
*/ SD.ze(P
publicclass Result { l&|{uk
6op\g].P
private Page page; X^.r@tT
[ThzLk#m
private List content; ]cA~%$c89s
I9Sh~vTm=u
/** h{JVq72R
* The default constructor ^|K*lI/
*/ F
Qk;
public Result(){ -{7N]q)}
super(); BuvBSLC~
}
;<][upn
_$cBI_eA7
/** 3+$O#>
* The constructor using fields #-f^;=7
* (qG$u&
* @param page uf>w* [m5
* @param content W
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*/ 3PEs$m9e
public Result(Page page, List content){ "Jwz.,Y\
this.page = page; GbE3:;JI
this.content = content; ]e3nnS1*.
} Y~:7l5C
e5/_Vga
/** c"$_V[m
* @return Returns the content. kj#yG"3+
*/ >I!(CM":s$
publicList getContent(){ Iymz2
return content; <f*0 XJ#
} '
#mC4\<W8
}* t~&l0
/** gi6_la+
* @return Returns the page. aF=VJ+5
*/ o&O!Ur
public Page getPage(){ p(8\w-6
return page; B::?
} <>Im$N ai
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/** $d=lDN
* @param content zW _'sC
* The content to set. YH>n{o;-
?
*/ ;@
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public void setContent(List content){
:+=*
this.content = content; ex1ecPpN
} %Fv)$ :b
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/** '$zFGq
}}
* @param page
jZ;T&s
* The page to set. 3{l"E(qqZ
*/ t|m3b~Oyv
publicvoid setPage(Page page){ 24Fxx9g
this.page = page; 34=0.{qn
} xpk|?/6
} Cw}\t!*!
cPbz7
O2e"TH3
#L)rz u
hA8 zXk/'8
2. 编写业务逻辑接口,并实现它(UserManager, 9 ?8`"v
K?4(o u
UserManagerImpl) 63HkN4D4
java代码: ob{pQx7
1N+#(<x@,
hqPn~Tq
/*Created on 2005-7-15*/ |@BN+o;`Om
package com.adt.service; Pa}vmn1$
l+6(|"md
import net.sf.hibernate.HibernateException; Z-@}~#E
o1Ln7r.
import org.flyware.util.page.Page; R=PzR;8
F0Hbklr
import com.adt.bo.Result; +b+sQ<w?.
2#3R]zIO
/** 3U)8P6Fz
* @author Joa <Xx\F56zp
*/ %5%Wo(W'
publicinterface UserManager { N+5^h(~
''uI+>Y
public Result listUser(Page page)throws WFP\;(YV
BvF_9
HibernateException; >U?Bka!
^A`(
} / JB4 #i7
KU,w9<~i(
SWpUVZyd
c'";36y
8n5nHne
java代码: I&8m5F?$`
zF&UdS3
z :v, Vu
/*Created on 2005-7-15*/ Y)}%SP>,
package com.adt.service.impl; OPW"ABJ
?bAFYF0!I
import java.util.List; (PcK(C!}=\
1m;*fs
import net.sf.hibernate.HibernateException; 8"mW!M
mthl?,I|
import org.flyware.util.page.Page; DA`sm
import org.flyware.util.page.PageUtil; t<F]%8S
<0)ud)~u
import com.adt.bo.Result; ROS"VV<
import com.adt.dao.UserDAO; siYRRr
import com.adt.exception.ObjectNotFoundException; E5G"QnxR>N
import com.adt.service.UserManager; n~u3
m\M+pjz
/** 2,V+?'^j
* @author Joa +\GZ(!~
*/ y*h1W4:^-
publicclass UserManagerImpl implements UserManager { cuaNAJ
(%y c5+f!
private UserDAO userDAO; !]+Z%ed`%
V}fKV6 v9
/** > '
0 ][~
* @param userDAO The userDAO to set. 6h6?BQSE
*/ wZ8 MhE
publicvoid setUserDAO(UserDAO userDAO){ .*-w UBr
this.userDAO = userDAO; B36puz 0{
} OP`Jc$|6
?%/u/*9rj
/* (non-Javadoc) 68<Z\WP
* @see com.adt.service.UserManager#listUser ~X<cG=p~u
7[v@*/W@
(org.flyware.util.page.Page) !{tiTA
*/ ttFY
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public Result listUser(Page page)throws }BdVD t
i4zV(
HibernateException, ObjectNotFoundException { z<%g
#bo
int totalRecords = userDAO.getUserCount(); IAF;mv}'
if(totalRecords == 0) U5CPkH1
throw new ObjectNotFoundException @ Rx6 >52>
7X{bB
("userNotExist"); wK'! xH^
page = PageUtil.createPage(page, totalRecords); nt0\q'&
List users = userDAO.getUserByPage(page); 4 %)N(%u
returnnew Result(page, users); \DU^idp#
} Z%5nVsm:G
MATgJ`lsy
} \}Acq;
mw(c[.*%
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}\f(qw
]oeuIRyQ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 u-QO>3oY6
>bA$SN
询,接下来编写UserDAO的代码: ;EJPrDHTk
3. UserDAO 和 UserDAOImpl: n{^<&GWox
java代码: nx-1*
UOWIiu
j&dx[4|m:h
/*Created on 2005-7-15*/ dv'E:R(a
package com.adt.dao; PW*;S p
4e+BqCriC*
import java.util.List; Y@]);MyL
V~T`&
import org.flyware.util.page.Page; 9^PRX
_,_8X7
import net.sf.hibernate.HibernateException; F_nZvv[H?
tE]5@b,R
/** my ;
* @author Joa 5#0A`QO
*/ $N;"}Gz
publicinterface UserDAO extends BaseDAO { r(:
8!=~K
`6Ureui2?
publicList getUserByName(String name)throws @PQrmn6w
lf%b0na?r
HibernateException;
AanH{
731h
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publicint getUserCount()throws HibernateException; bQwdgc),s{
3P//H88LY
publicList getUserByPage(Page page)throws CKv&Re
J>=1dCK
HibernateException; %Kh2E2Pe
`'p`PyMt`
} 3 ppuQQ
uAu( +zV2
8[{|xh(
3`58ah
f}[H
`OF
java代码: !0Idp%
\Okc5;kB2
8f?rEI\0GD
/*Created on 2005-7-15*/ aS,a_b]
package com.adt.dao.impl; =op`fn%
Ovvny$
import java.util.List; 9nn>O?
6nh]* /
import org.flyware.util.page.Page; LeY+p]n~
( %[Tk[
import net.sf.hibernate.HibernateException; ZB828T3
import net.sf.hibernate.Query; aH%ZetLNJ
}6).|^]\'
import com.adt.dao.UserDAO; Mx8Gu^FW.d
u7HvdLql
/** Iz#yQ`
* @author Joa #(6) ^ (
*/ A2y6UzLYD
public class UserDAOImpl extends BaseDAOHibernateImpl -yoAxPDW
kI%peb?
implements UserDAO { h40'@u^W
~n
WsP}`n
/* (non-Javadoc) M;*$gV<x
* @see com.adt.dao.UserDAO#getUserByName 6/| 0+G^
R:"+ #Sq
(java.lang.String) )!e3.C|V1W
*/ AH^e]<2-
publicList getUserByName(String name)throws ABc)2"i:*
.U9R>#
HibernateException { &y70
String querySentence = "FROM user in class 8h|M!/&2
}!8nO;
com.adt.po.User WHERE user.name=:name"; abBO93f^
Query query = getSession().createQuery 'WQdr(
f])M04<
(querySentence); o~#f1$|Xn
query.setParameter("name", name); qe$33f*
return query.list(); Pt)S;6j
} ca(U!T68
GW3>&j_!d
/* (non-Javadoc) rfs (#
* @see com.adt.dao.UserDAO#getUserCount() Lz@$3(2
*/ w9f
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publicint getUserCount()throws HibernateException { 5;mRGY
int count = 0; KY$k`f6?P
String querySentence = "SELECT count(*) FROM '. (~
H<`\bej,
user in class com.adt.po.User"; &vkjmiAS
Query query = getSession().createQuery p&^J=_O
i@5)`<?
(querySentence); 537?9
count = ((Integer)query.iterate().next r<c #nD~K
:"<e0wDu[
()).intValue(); X&a:g
return count; M+poB+K.
} <~{du ?4n
oQT2S>cm^
/* (non-Javadoc) "_< 9PM1t
* @see com.adt.dao.UserDAO#getUserByPage byGn,m
dU]/$7
(org.flyware.util.page.Page) h?Nek+1'
*/ eY,O@'"8`
publicList getUserByPage(Page page)throws +-BwQ{92[:
5Fbs
WW2
HibernateException { 53Yxz3v
String querySentence = "FROM user in class +C+<BzR~A.
`G!M>h@
com.adt.po.User"; 2&he($HIzg
Query query = getSession().createQuery Wd8Ru/
sw;|'N$:<
(querySentence); &!L:"]=+
query.setFirstResult(page.getBeginIndex()) |=6_ xRyr
.setMaxResults(page.getEveryPage()); W.I\J<=V
return query.list(); Eectxyr?;N
} kWhr1wR1
m$wlflt
} 4)kG-[#
epg#HNP7^Y
,LhCFw{8?~
&nj&:?w
$s-Y%gc
至此,一个完整的分页程序完成。前台的只需要调用 YKZa$@fA?
Y?K{(szo ?
userManager.listUser(page)即可得到一个Page对象和结果集对象 ZnW@YC#9
y_p.Gzy(^}
的综合体,而传入的参数page对象则可以由前台传入,如果用 IiJZ5'{
lg$zGa?
webwork,甚至可以直接在配置文件中指定。 zMi; A6
^D{lPu
3
下面给出一个webwork调用示例: pH@]Y+W
java代码: YA:nOvd@O
IkPN?N
%NHkDa!
/*Created on 2005-6-17*/ lIRlMLuG
package com.adt.action.user; NZ0O,}m
)%d*3\Tsd
import java.util.List; QHq,/kWY
Ztr Cv?
import org.apache.commons.logging.Log; n>>Qn&ym
import org.apache.commons.logging.LogFactory; (kv?33
import org.flyware.util.page.Page; r!PpUwod
J aTp}#
import com.adt.bo.Result; #_93f
|
import com.adt.service.UserService; *)M49a*UD
import com.opensymphony.xwork.Action; !%)F J:p
TS2ZF{m
/** }7E^ZZ]f
* @author Joa 0'YG6(h
*/ G+UMBn
publicclass ListUser implementsAction{ 2;a(8^n
Zwz&