Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XI:+EeM?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f*:N*cC
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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 /l$fQ:l
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 GPizR|}h
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分页支持类: 03AQB;.
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java代码: KYy oN
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package com.javaeye.common.util; [?=DPE%
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import java.util.List; m^zD']
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publicclass PaginationSupport { f'MRC
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publicfinalstaticint PAGESIZE = 30; A
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privateint pageSize = PAGESIZE;
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privateList items; Vx:uqzw#
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privateint totalCount; 4uH}
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privateint[] indexes = newint[0]; z8r?C
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privateint startIndex = 0; &xvNR=K[`
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public PaginationSupport(List items, int e\O625
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totalCount){ P8H2v_)X&
setPageSize(PAGESIZE); SmRFxqtN
setTotalCount(totalCount); unRFcjEa
setItems(items); @+_pj.D
setStartIndex(0); NGRXNh+
} FjI1'Ah\
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public PaginationSupport(List items, int fB&i{_J
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totalCount, int startIndex){ z
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setPageSize(PAGESIZE); VZe'6?#
setTotalCount(totalCount); Q<DXDvL
setItems(items); >s!k"s,
setStartIndex(startIndex); Y9
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} xT( pB-R
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public PaginationSupport(List items, int 9xK#(M
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totalCount, int pageSize, int startIndex){ WRRR "Q$
setPageSize(pageSize); !b+!] 2~g}
setTotalCount(totalCount); P(o>UDy
setItems(items); t8; nP[`
setStartIndex(startIndex); :o87<)
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} +;*4.}
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publicList getItems(){ J9f]=1`
return items; [g}0.J`_
} ![eY%2;<
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publicvoid setItems(List items){ &LG|YvMY6
this.items = items; eYn/F~5-
} '
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publicint getPageSize(){ n
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return pageSize; HX,i{aWWy
} ~0o>B$xJ
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publicvoid setPageSize(int pageSize){ 56u_viZ=8
this.pageSize = pageSize; ~9,Fc6w4`+
} sHV?njZd
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publicint getTotalCount(){ \4
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return totalCount; `,Y3(=3Xe?
} rmFcSolt,f
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publicvoid setTotalCount(int totalCount){ \IEuu^
if(totalCount > 0){ |oePB<N
this.totalCount = totalCount; \@T;/Pj{[
int count = totalCount / sPl3JP&s
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pageSize; h0A%KL
if(totalCount % pageSize > 0) &" 5Yt&{
count++; 91nB?8ZE6,
indexes = newint[count]; %h;1}SFl0
for(int i = 0; i < count; i++){ TTWiwPo59
indexes = pageSize * |+JC'b?,
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} Z.rhM[*+0C
}else{ >z%WW&Z'
this.totalCount = 0; ~BE=z:
} :~ 	
} tO D}&
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publicint[] getIndexes(){ ]US!3R^
return indexes; AM#s2.@
} :QHh;TIG=<
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publicvoid setIndexes(int[] indexes){ r^ '
this.indexes = indexes; RMid}BRE
} DK'S4%;Sp
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publicint getStartIndex(){ Gv[(0
return startIndex; Y:Jgr&*,z
} dQAF;L
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publicvoid setStartIndex(int startIndex){ QF22_D<.}J
if(totalCount <= 0) 0HQTe>!
this.startIndex = 0; b&d4(dk
elseif(startIndex >= totalCount) *iyc,f^w
this.startIndex = indexes jR+kx:+
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[indexes.length - 1]; #BgiDLh
elseif(startIndex < 0) +CXq41g"c
this.startIndex = 0; {d)L0KXK
else{ hvA|d=R(
this.startIndex = indexes m%.[|sZ3EM
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[startIndex / pageSize]; uu>R)iTQ%S
} Zw<<p|{)<
} ?+%bEZ`
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publicint getNextIndex(){ V?jWp$
int nextIndex = getStartIndex() + #/_ VY.
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pageSize; r]aI=w<(f
if(nextIndex >= totalCount) WD*z..`
return getStartIndex(); WY5HmNX3E
else i'1MZ%.
return nextIndex; I=
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} PIoBK CJ
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publicint getPreviousIndex(){ -[h|*G.J
int previousIndex = getStartIndex() - M=4b
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pageSize; m}>Q#IVZ
if(previousIndex < 0) A>RK3{7
return0; }gE^HH'
else <7gv<N6BQf
return previousIndex; _kBx2>qQ
} Jc` tOp5
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} 5{v uN)K3
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抽象业务类 UgZL<}
java代码: g'2;///
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/** mHH>qW{`
* Created on 2005-7-12 .*J /F$
*/ PR,8c
package com.javaeye.common.business; VtGZB3
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import java.io.Serializable; aB`jFp-
import java.util.List; T#[#w*w/
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; $s 'n]]Wq
import org.hibernate.Session; g8"H{u
import org.hibernate.criterion.DetachedCriteria; n?9FJOqi
import org.hibernate.criterion.Projections; d'b9.ki\
import 7*He 8G[W
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org.springframework.orm.hibernate3.HibernateCallback; }_7
import k<NxI\s8]
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org.springframework.orm.hibernate3.support.HibernateDaoS 7")~JBH
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upport; tX,x% (
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import com.javaeye.common.util.PaginationSupport; +/" \.wYv
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public abstract class AbstractManager extends 2zuQeFsK
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HibernateDaoSupport { I<+:Ho=6
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privateboolean cacheQueries = false; N:Ir63X*#
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privateString queryCacheRegion; Q^* 33
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publicvoid setCacheQueries(boolean 3.KNAObO
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cacheQueries){ J@#rOOu
this.cacheQueries = cacheQueries; tZu1jBO_Q4
} s=556
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publicvoid setQueryCacheRegion(String k~,
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queryCacheRegion){ O%px>rdkY
this.queryCacheRegion = ud"Kko Rt
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queryCacheRegion; wxT(ktE
} QV4FA&f&
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publicvoid save(finalObject entity){ Yb1Q6[!
getHibernateTemplate().save(entity); a>Zp?*9
} sk
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publicvoid persist(finalObject entity){ k+Z2)j"
getHibernateTemplate().save(entity); [khXAf1{Q
} g}L>k}I?!W
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publicvoid update(finalObject entity){ l kyK
getHibernateTemplate().update(entity); 2IUd?i3~l
} ;mPX8bT
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publicvoid delete(finalObject entity){ *dPbV.HCl
getHibernateTemplate().delete(entity); 81w"*G5AM
} c%1{l]
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publicObject load(finalClass entity, Mz\l
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finalSerializable id){ <y&&{*KW8m
return getHibernateTemplate().load Ys&)5j-
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(entity, id); ? PpS4Rd
} e*U6^Xex
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publicObject get(finalClass entity, R'" c
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finalSerializable id){ 'g3T'2"`5
return getHibernateTemplate().get +(^HL3
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(entity, id); u(\O@5a
} -Zp BYX5e_
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publicList findAll(finalClass entity){ sV\K[4HG
return getHibernateTemplate().find("from LWhPd\
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" + entity.getName()); ia_lP
} "M3;>"`G
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publicList findByNamedQuery(finalString S5d
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namedQuery){ 1l Cr?
return getHibernateTemplate OkfxX&n
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().findByNamedQuery(namedQuery); \Pcn D$L
} dC|6z/
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publicList findByNamedQuery(finalString query, `*U$pg
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finalObject parameter){ t[@>u'YKt
return getHibernateTemplate \O\q1
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().findByNamedQuery(query, parameter); QHc([%oV
} O%N. ;Ve
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publicList findByNamedQuery(finalString query, jL'`M%8O
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finalObject[] parameters){
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return getHibernateTemplate e`OQ6|.k8
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().findByNamedQuery(query, parameters); 5$+ssR_?k
} iRbe$v&N
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publicList find(finalString query){ 0/9]TIc
return getHibernateTemplate().find ivyaGAF}+o
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(query); YPf?
} `b%lojT.
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publicList find(finalString query, finalObject e =r
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parameter){ )nFyHAy-
return getHibernateTemplate().find u05Yy&(f
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(query, parameter); $mh\`
} D9?.Ru0.
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public PaginationSupport findPageByCriteria 0U H]
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(final DetachedCriteria detachedCriteria){ Z#bO}!
return findPageByCriteria yMTO 5~U{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -a &<Un/
} 4e#$-V
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public PaginationSupport findPageByCriteria )%3T1
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(final DetachedCriteria detachedCriteria, finalint C4P<GtR9
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startIndex){ qb/}&J7+
return findPageByCriteria o. ;Vrc
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(detachedCriteria, PaginationSupport.PAGESIZE, o:fe`#t
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startIndex); CxZh^V8LP
} l`i97P?/W
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public PaginationSupport findPageByCriteria 2E[7RBFY+\
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(final DetachedCriteria detachedCriteria, finalint ]JV'z<
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pageSize, (QJe-)0_y
finalint startIndex){ rp{|{>'`.q
return(PaginationSupport) x3Y)l1gh
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getHibernateTemplate().execute(new HibernateCallback(){ tiHR&v
publicObject doInHibernate q$mc{F($D
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(Session session)throws HibernateException { .V?[<}OJn
Criteria criteria = 8/BMFRJ
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detachedCriteria.getExecutableCriteria(session); D
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int totalCount = \6JOBR
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((Integer) criteria.setProjection(Projections.rowCount #mA(x@:*
OTdijQLY
()).uniqueResult()).intValue(); AyOibnoZ2E
criteria.setProjection rxH]'6kP
1{
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(null); qS FtQ4
List items = jWv'`c
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criteria.setFirstResult(startIndex).setMaxResults E3]WRF;l
So'.QWzX
(pageSize).list(); =4a:)g'
PaginationSupport ps = +8T^q,
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new PaginationSupport(items, totalCount, pageSize, ~~Ezt*lH
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startIndex); .
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return ps; Cl]?qH*:
} @XV&^l-
}, true); ACdPF_Y]
} h%Nd89//
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public List findAllByCriteria(final A>1$?A8Q
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DetachedCriteria detachedCriteria){ I}3F'}JV<
return(List) getHibernateTemplate 4^F%bXJ)
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().execute(new HibernateCallback(){ O'mcN*
publicObject doInHibernate hEQyaDD;
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(Session session)throws HibernateException { r~j
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Criteria criteria = DylO;+
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detachedCriteria.getExecutableCriteria(session); YAOfuas]j
return criteria.list(); ?<TJ}("/
} 89g
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}, true); JfIXv
} MK=oGzK
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ V0>X2&.A
Integer count = (Integer) >8>!wi9U
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getHibernateTemplate().execute(new HibernateCallback(){ =GPXuo
publicObject doInHibernate 3k`Q]O=OU
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(Session session)throws HibernateException { v$|~
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Criteria criteria = 3SP";3+
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detachedCriteria.getExecutableCriteria(session); m-vn5OX
return K)7T]z`
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criteria.setProjection(Projections.rowCount 8(L$a1#5W
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()).uniqueResult(); G?1GkR
} 5@w6pda
}, true); W2
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return count.intValue(); oAQQ OtpZN
} /\w4k
} f^uiZb
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用户在web层构造查询条件detachedCriteria,和可选的 \9)5b8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <l{oE?N
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PaginationSupport的实例ps。 &zdS9e-fF
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ps.getItems()得到已分页好的结果集 Rql/@j`JX
ps.getIndexes()得到分页索引的数组 ga5Q
ps.getTotalCount()得到总结果数 9\_AB.Z:
ps.getStartIndex()当前分页索引 V`^*Z}d9
ps.getNextIndex()下一页索引 ("2X8(3z
ps.getPreviousIndex()上一页索引 fp' '+R[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~~W.]>f
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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 $oBs%.Jp
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一下代码重构了。 :?6HG_9X
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我把原本我的做法也提供出来供大家讨论吧: &Hb%Q! ^Kb
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首先,为了实现分页查询,我封装了一个Page类: 7g\v (P
java代码: o$*(N
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/*Created on 2005-4-14*/ 5n3yc7NPP
package org.flyware.util.page; \f9WpAY
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/** ,hn#DJ)
* @author Joa
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* 7;EDU
*/ cRLw)"|
publicclass Page { ,HZ%q]*:~
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/** imply if the page has previous page */ 2{79,Js0
privateboolean hasPrePage; uy{O
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/** imply if the page has next page */ A8'RM F1
privateboolean hasNextPage; ^Arv6kD,
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/** the number of every page */ tbS hSbj
privateint everyPage; Cn~VJ,l
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/** the total page number */ YSP\+ZZ
privateint totalPage; ]Dq6XR
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/** the number of current page */ b Hr^_ogN
privateint currentPage; IuXgxR%
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/** the begin index of the records by the current $${I[2R)
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query */ 7{m>W!
privateint beginIndex; 3``JrkPI
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/** The default constructor */ t2dsYU/
public Page(){ sX1DbEjj[o
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} w"'
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/** construct the page by everyPage :h(HKMSk1
* @param everyPage ?X|)0o
* */ [MIgQ.n
public Page(int everyPage){ cY5&1Shb~
this.everyPage = everyPage; 05wkUo:9
} v@\S$qU2
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/** The whole constructor */ _.s,gX
public Page(boolean hasPrePage, boolean hasNextPage, Qt.*Z;Gs
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int everyPage, int totalPage, f;'*((
int currentPage, int beginIndex){ >=N-P<%
this.hasPrePage = hasPrePage; lh;fqn`
this.hasNextPage = hasNextPage; 8jz>^.-o
this.everyPage = everyPage; !aT:0m$:9c
this.totalPage = totalPage; ?}?"m:=
this.currentPage = currentPage; Ow;thNN
this.beginIndex = beginIndex; _[6sr7H!
} kkl'D!z2g
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/** h.Qk{v
* @return 7!J-/#!
* Returns the beginIndex. Jqxd92 bI
*/ "1a;);S=*)
publicint getBeginIndex(){ |ke0G
return beginIndex; %+'Ex]B
} 2K:A4)jZ
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/** i9ySD
* @param beginIndex Vlx.C~WYn
* The beginIndex to set. }TTghE!
*/ <+*0{8?0
publicvoid setBeginIndex(int beginIndex){ f/Y&)#g>k
this.beginIndex = beginIndex; #zsaQg,
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} +?)7l
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/** v< P0f"GH
* @return a"@f< wU~
* Returns the currentPage. $OZ= L
*/ kZ5#a)U<
publicint getCurrentPage(){ Z^'~iU-?
return currentPage; !.UE} ^TV
} ?|ZbQz(bL
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/** zQ+Mu^|u+
* @param currentPage D9+qT<ojN
* The currentPage to set. 3wfcGQn|sD
*/ C_J@:HlJ
publicvoid setCurrentPage(int currentPage){ 336ETrG^0
this.currentPage = currentPage; s)WA9PiC
} ~\am%r>
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/** ^}P94( oz
* @return >5t!
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* Returns the everyPage. qWH^/o
*/ J$6WU z:?
publicint getEveryPage(){ Z]Bv
return everyPage; P^OmJ;""D
} }-fHS;/
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/** O7 ;=g!j
* @param everyPage nT?+^Ruc
* The everyPage to set. 2OoANiX
*/ L(|K{vH h]
publicvoid setEveryPage(int everyPage){ 1Le8W)J
this.everyPage = everyPage; gnH{_
} tMw65Xei6b
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/** ,\i*vJ#f
* @return X$UK;O
* Returns the hasNextPage. ?3~t%Q`
*/ vb[0H{TT2
publicboolean getHasNextPage(){ "73*0'm
return hasNextPage; jSpj6:@B
} l,J>[Q`<
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/** =0?5hxM d
* @param hasNextPage Movm1*&=
* The hasNextPage to set. KKsVZ~<6u
*/ ^N^G?{EV/#
publicvoid setHasNextPage(boolean hasNextPage){ sUlf4<_zW
this.hasNextPage = hasNextPage; [2,D] e
} I/w;4!+)
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/** ;t*SG*Vi
* @return Gy\]j
* Returns the hasPrePage. (l%?YME
*/ 68j1svz9
publicboolean getHasPrePage(){ ,<
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return hasPrePage; HN7tIz@Frc
} Jk%5Fw0
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/** C<=rnIf'
* @param hasPrePage
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* The hasPrePage to set. m]V#fRC
*/ \d;)U4__!
publicvoid setHasPrePage(boolean hasPrePage){ IM1&g7Qs2
this.hasPrePage = hasPrePage; =Fc]mcJ69
} [\3ZMH
*
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/** rA
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* @return Returns the totalPage. se.HA
* ?lkB{-%rQ
*/ @2T8H
publicint getTotalPage(){ }vh
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return totalPage; _FOIMjh%N
} d:hnb)I$*
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/** nl}LT/N
* @param totalPage |yz[mP*;o
* The totalPage to set. FaCW +9B
*/ 07Yak<+~
publicvoid setTotalPage(int totalPage){ w)|9iL8
this.totalPage = totalPage; pfZ[YC-
} FdE?uw
hrnE5=iY
} &jY|
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Qw5-/p=t
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个PageUtil,负责对Page对象进行构造: WyOav6/*K^
java代码: 1n<4yfJ
4AzDWK@/
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/*Created on 2005-4-14*/ AS]8rH
package org.flyware.util.page; ;`/a. /bc
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import org.apache.commons.logging.Log; s<LnUF1b
import org.apache.commons.logging.LogFactory; x"sbm
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/** a&0g0n6
* @author Joa pq
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* cBqbbZyUk
*/ d BB?A~
publicclass PageUtil { c/ImK`:)4a
cz,CL/rno
privatestaticfinal Log logger = LogFactory.getLog OLIMgc(W
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(PageUtil.class); q]yw",muT
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/** D}
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* Use the origin page to create a new page k={1zl ;
* @param page sCw>J#@2>
* @param totalRecords UF^[?M =
* @return 6O,k! y>
*/ #w%-IhP
publicstatic Page createPage(Page page, int 7[P-;8)tq
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totalRecords){ 0^tY|(b3/M
return createPage(page.getEveryPage(), E`.hM}h
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page.getCurrentPage(), totalRecords); Xg]Cq"RJC
} Rd7U5MBEF
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/** eI"pRH*f
* the basic page utils not including exception %\-E
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h STcL:b
handler _cJ)v/]
* @param everyPage N$Ad9W?T
* @param currentPage 5.ab/uk;M
* @param totalRecords @:RoY vk$
* @return page Dqo#+_v
*/
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publicstatic Page createPage(int everyPage, int *Sdx:G~gp
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currentPage, int totalRecords){ ~tWh6-:|{J
everyPage = getEveryPage(everyPage); c_ncx|dUs
currentPage = getCurrentPage(currentPage); LI@BB:)[
int beginIndex = getBeginIndex(everyPage, #8M?y*<I
:QP1!
currentPage); ~}j+~
int totalPage = getTotalPage(everyPage, f8[O]MrO;
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totalRecords); ,x1OQ jtY
boolean hasNextPage = hasNextPage(currentPage, @@^iN~uf
y akRKiz\
totalPage); pt"9zkPj
boolean hasPrePage = hasPrePage(currentPage); T0dD:s N
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returnnew Page(hasPrePage, hasNextPage, a(6h`GHo
everyPage, totalPage, @*<0:Q|m
currentPage, Nc(CGl:
mST8+R@S
beginIndex); Lhp&RGy
} UH6 7<_mK
9vyf9QE;
privatestaticint getEveryPage(int everyPage){ JDR_k
return everyPage == 0 ? 10 : everyPage; Uc:NW
} e(/F:ZEh
!@ ]IJ"\
privatestaticint getCurrentPage(int currentPage){ *GoTN
return currentPage == 0 ? 1 : currentPage; ssLswb
} >w<w*pC
U!-Nx9
privatestaticint getBeginIndex(int everyPage, int E \DA3lq
:0B 7lDw
currentPage){ Z5(9=8hB/
return(currentPage - 1) * everyPage; X-nC2[tu'W
} mj$Ucql
6 /YJA*
privatestaticint getTotalPage(int everyPage, int Le?g,c
>Y8\f:KQ
totalRecords){ uarfH]T{
int totalPage = 0; FfM^2`xP
MZ$uWm`/
if(totalRecords % everyPage == 0) 5C1EdQ4S0
totalPage = totalRecords / everyPage; (o IGp
else |?VJf3A
totalPage = totalRecords / everyPage + 1 ; -GFZFi
CnL=s6XD'
return totalPage; PlH~um[J
} -!_8>r;Q4
Kw`CN
privatestaticboolean hasPrePage(int currentPage){ BZ:tVfg.
return currentPage == 1 ? false : true; T 'c39
} B2j1GJEO
=[]6NjKS,
privatestaticboolean hasNextPage(int currentPage, ciODTq?
3E*m.jX
int totalPage){ [s[ZOi!;I
return currentPage == totalPage || totalPage == e^\e;>Dh>
Gqd|F>
0 ? false : true; l~;>KjZg
} \t=0rFV)t
Godrz*"
=W3
K6w
} rWL;pM<
) %Fwfb
lvWwr!w
?< b{
J?3/L&seA
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。 )pHlWi|h
7?R600OA
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 dWQsC|
GKo&?Tj)
做法如下: 8-x-?7
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 70 7( LG
o p9dYjG7
的信息,和一个结果集List: b*?u+tWP_
java代码: ?p@J7{a
`5@F'tKQ
K{ar)_V/
/*Created on 2005-6-13*/ .c-a$39
package com.adt.bo; &$/
#"lW,V
d)vP9vXy
import java.util.List; oV:oc,
D;C';O
import org.flyware.util.page.Page; IANSpWea?
o0 C&ol_
/** 1]G)41
* @author Joa (|^m9v0:
*/ RN(I}]] a
publicclass Result { \i_E}Ii0
.^{%hc*w4
private Page page; WChP,hw
hNN[dj R
private List content; /dYv@OU?
p@G7}'|eyA
/** nU_O|l9
* The default constructor -Ty~lZ)TDT
*/ !}TsFa
public Result(){ kh0cJE\_^
super(); 4uIYX
} EpAgKzVpJ
Z71m(//*}
/** e7U\gtZ.
* The constructor using fields {zAI-?#*u
* qazA,|L!
* @param page +\Vm t[v
* @param content Kb?{^\FiU
*/ ~'_cBJ
'XD
public Result(Page page, List content){ ;yJ:W8U]+;
this.page = page; o]oiJvOr
this.content = content; &+2l#3}
} ,_3hbT8Q
tz@MZs09
/** 1.!U{>$
* @return Returns the content. }9S}?R
*/ 0y9 b0G
publicList getContent(){ KRaL+A
return content; LQR2T5S/Q,
} 4qie&:4j
F]3Y,{/V
/** s7Agr!>f
* @return Returns the page. B`}um;T#~,
*/ P'Rw/co
public Page getPage(){ iT-coI
return page;
*V6|
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} '{d@Gc6.
B'}?cG]
/** p)IL(_X)
* @param content y>a?<*Y+e
* The content to set. y'_8b=*
*/ Ym6d'd<9(
public void setContent(List content){ {.:$F3T
this.content = content; [%.v;+L
} 3gi)QCsk
E^i]eK*"
/** &$
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* @param page KG'i#(u[
* The page to set. ]Btkoad
*/ hk~/W}sI
publicvoid setPage(Page page){ W" 5nS =d%
this.page = page; 7<yc:}9nx
} LCHMh6
} TQ4@|S:OF
{6'Xz
L|'^P3#7`
>pU9}2fpT
-* ,CMw
2. 编写业务逻辑接口,并实现它(UserManager, $O%{l.-O
nYyhQX~]B
UserManagerImpl) @RoZd?
java代码: ^LMgOA(7
,'X"(tpu@
L^+rsxR
/*Created on 2005-7-15*/ VPUVPq~&
package com.adt.service; "}]$ag!`q$
(GSP3KKo*G
import net.sf.hibernate.HibernateException; Cu[-<>my
(>v'0RA
import org.flyware.util.page.Page; \/NF??k,jk
?%s>a8w
import com.adt.bo.Result; x}] 56f
BN_h3|)
/** |9I)YD
* @author Joa ~ nsb
*/ 4V,.Oi
publicinterface UserManager { $GJT
x|6]+?l@6
public Result listUser(Page page)throws '.mepxf< f
k +-w%
HibernateException; _[2@2q0
S&-K!XyJ
} oh9
;_~
jm^.E\_
|YJ83nSO~
]O@$}B];)
d?2V2`6
java代码: &|hK79D
2c9?,Le/;
]b4WfIu
/*Created on 2005-7-15*/ *M.xVUPr
package com.adt.service.impl; (eN7s_
j6rN t|
import java.util.List; ";K w?
>fPo_@O
import net.sf.hibernate.HibernateException; QZ a.c
pO`KtagL
import org.flyware.util.page.Page; P49\A^5S!
import org.flyware.util.page.PageUtil; @+u>rS|IB
d ]P~
import com.adt.bo.Result; &k}f"TX2
import com.adt.dao.UserDAO; "s+4!, k
import com.adt.exception.ObjectNotFoundException; r"7n2
import com.adt.service.UserManager; 4DA34m(
~^mUu`@r
/** [{x}# oRSE
* @author Joa xnP!P2
*/ ^jdU4
publicclass UserManagerImpl implements UserManager { t^rw@$"}
t'qYM5
private UserDAO userDAO; %By Pwu:f
9j,g&G.K
/**
n>M`wF>
* @param userDAO The userDAO to set. .w2 ID
*/ .Mt3ec<
publicvoid setUserDAO(UserDAO userDAO){ 22\!Z2@T/
this.userDAO = userDAO; EYAaK^ &
} \(o"/*
f-b],YE
/* (non-Javadoc) /R)wM#&
* @see com.adt.service.UserManager#listUser >[}oH2oi
hx;f/EPx
(org.flyware.util.page.Page) OrY[
*/ ^Co-!jM
public Result listUser(Page page)throws Zi!Ta"}8
r* *zjv>
HibernateException, ObjectNotFoundException { M^FY6TT4O
int totalRecords = userDAO.getUserCount(); c`;\sW-_W
if(totalRecords == 0) zzqJeIS
throw new ObjectNotFoundException Uzu6>yT
[M?2axOC
("userNotExist"); HgI!q<)
page = PageUtil.createPage(page, totalRecords); x]~TGzS
List users = userDAO.getUserByPage(page); w0pMH p'Y
returnnew Result(page, users); W yL+HB}
} dAo;y.3
Rj8%% G-pt
} 8%?y)K^
D
K1B9t{T
MmuT~d/
kB\{1;
E~'mxx~i
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {T){!UVp!
*b~6 B M$
询,接下来编写UserDAO的代码: p?@ %/!S
3. UserDAO 和 UserDAOImpl: @mp`C}x"0&
java代码: je4l3Hl
bDI%}k9#
6@S6E(^
/*Created on 2005-7-15*/ :2 ;Jo^6Se
package com.adt.dao; KyvZ?R
Tb/TP3N
import java.util.List; M>8J_{r^
I[\~pi,
import org.flyware.util.page.Page; UM}u(;oo%)
}pc9uvmIJ
import net.sf.hibernate.HibernateException; O] _4pP
7nZPh3%
/** e#eVc'=cDR
* @author Joa x&}]8S)
*/ *GP2>oEM
publicinterface UserDAO extends BaseDAO { jG5HW*>k0
nB[-KS
publicList getUserByName(String name)throws '%)R}wgV
*{o7G a
HibernateException; 0D X_*f
.6B\fr.za
publicint getUserCount()throws HibernateException; <g4}7l8
.R9Z$Kbq
publicList getUserByPage(Page page)throws e|~MJu+1
XR5KJl
HibernateException; Xlo7enzY
wb-yAQ8
} IgT`on3Y
t>"%exdoZ
sE1cvAw9l
Z 6jEj9?O
Mf}M/Fh
java代码: wBPo{
ITu19WG
En5oi
/*Created on 2005-7-15*/ [3%mNNk
package com.adt.dao.impl; M>Q]{/V7T
lOIk$"Ne
import java.util.List; x 3@-E
oFY!NMq}:
import org.flyware.util.page.Page; ON ?Y
Df
jYsAL=oh,*
import net.sf.hibernate.HibernateException; c/{FDN
import net.sf.hibernate.Query; >.h:Y5
,Z.sGv
import com.adt.dao.UserDAO; Rx%S<i;9
^5mc$~1`
/** _n&Nw7d2
M
* @author Joa ngY%T5-
*/ n,la<N]
public class UserDAOImpl extends BaseDAOHibernateImpl Bq0 \T
0,
/--p#G h'
implements UserDAO { t6+m` Kq
)?n'ZhsX
/* (non-Javadoc) "Fz.#U
* @see com.adt.dao.UserDAO#getUserByName "gM^o
>rnVTK
(java.lang.String) Z$oy;j99y
*/ h}bfZL
publicList getUserByName(String name)throws E?m~DYnU
q76POytV|
HibernateException { 0=d2_YzSf
String querySentence = "FROM user in class ;C]Ufk
h}b:-a
com.adt.po.User WHERE user.name=:name"; xNz(LZ.c
Query query = getSession().createQuery #-hO\
QdC
UHBXq;?&q
(querySentence); K^-1M?
query.setParameter("name", name); w~'xZ?
return query.list(); 9&Y@g)+2
} *zfgO pK
:yay:3qv
/* (non-Javadoc) h8rW"8Th
* @see com.adt.dao.UserDAO#getUserCount() Fu7:4+
*/ x)5}:b1B=
publicint getUserCount()throws HibernateException { 5*0zI\
int count = 0; jX53 owZ
String querySentence = "SELECT count(*) FROM [^H2'&]
xn8KOwX%
user in class com.adt.po.User"; Et>#&Nw8
Query query = getSession().createQuery qTO6I5u
Z\0Rw>#
(querySentence); 3;nOm =I
count = ((Integer)query.iterate().next a6p0_-MF
0^;2
()).intValue(); K g@'mG
return count; f%Q)_F[0D4
} jm0p%%z
_=v#"l
/* (non-Javadoc) +z
>)'#
* @see com.adt.dao.UserDAO#getUserByPage VK}4<u
y@P%t9l
(org.flyware.util.page.Page) De $AJl
*/ "W<Y1$Y=Y
publicList getUserByPage(Page page)throws _0/unJl`
Dc9uq5l
HibernateException { k.@![w\ea
String querySentence = "FROM user in class #A63?kDE&&
8-$t7bV5
com.adt.po.User"; ?W/.'_
Query query = getSession().createQuery 0zt]DCdY
dj gk7
(querySentence); uo F.f$%"
query.setFirstResult(page.getBeginIndex()) ^$c#L1
C
.setMaxResults(page.getEveryPage()); |OQ]F
return query.list(); `FHudSK
} F^ q{[Z
4vhf!!1
} R|;BO:S1
1#vy# '
G5ATR<0m
sqkWQ`Ur
AGhenDNV
至此,一个完整的分页程序完成。前台的只需要调用 *X5)9dq
]>3Y~KH(
userManager.listUser(page)即可得到一个Page对象和结果集对象 'Waazk[@O
X2w)J?pv
的综合体,而传入的参数page对象则可以由前台传入,如果用 X+vKY
I8H3*DE
webwork,甚至可以直接在配置文件中指定。 K.tNV{OL
W"{Ggk`
下面给出一个webwork调用示例: l1KMEGmG
java代码: hCxg6e<[
hA=uoe\
y:G%p3h)[
/*Created on 2005-6-17*/ m$0W^u
package com.adt.action.user; EOPx4+o
CTMC78=9}
import java.util.List; Nc[@QC{
A l[ZU
import org.apache.commons.logging.Log; wO??"${OH
import org.apache.commons.logging.LogFactory; R >x d*A
import org.flyware.util.page.Page; Y;'<u\^M"
D
0Xl`0"'
import com.adt.bo.Result; wMa8HeBE\
import com.adt.service.UserService; %ms%0%
import com.opensymphony.xwork.Action; U-|]A\`)I
ly0R'4j \
/** g_>&R58
* @author Joa y^2#;0W
*/ qHt/,w='Q
publicclass ListUser implementsAction{ VKa+[
*V>?m6y/
privatestaticfinal Log logger = LogFactory.getLog 7FX4|]
Pz)lq2Zm9
(ListUser.class); h nydH-;cz
*ug~LK5Y.
private UserService userService; \w9}O2lL
WfPb7T
private Page page; =m.Nm -g
>$Y/B=e
privateList users; xAmtm"
S^O9}<2g
/* YQ0#j'}/
* (non-Javadoc) ^[<BMk
* @ @[xTyA
* @see com.opensymphony.xwork.Action#execute() Nt>^2Mv
*/ fit{n]g
publicString execute()throwsException{ 6w.E Sm
Result result = userService.listUser(page); vCa8`m
page = result.getPage(); 3%v)!dTa<^
users = result.getContent(); Vl.,e1)6
return SUCCESS; :Cq73:1\B
} NuZ2,<~9
]b-2:M
/** )O'LE&kQ|
* @return Returns the page. {f06Ki
*/ Gxr\a2Z&r%
public Page getPage(){ -wU]L5uP
return page; (/y8KG3
} =<]`'15"V
&V4Zmn?UU
/** d/_D|ivZ=
* @return Returns the users. b6k`R4S3
*/ o78u>O y
publicList getUsers(){ sn"((BsO<
return users; ^'3c%&Zf3
} jY6GWsh:9
(p]FI# y
/** ?Y"%BS+pt
* @param page 161P%sGx2
* The page to set. ,Ckcc
*/ :7e*- '
publicvoid setPage(Page page){ gt{kjrTv&
this.page = page; _CD~5EA:
} WD5J2EePT
2A_1 E\
/** MQ,K%_m8
* @param users IQ&PPC
* The users to set. WNR]GI
*/ s|C[{n<_
publicvoid setUsers(List users){ s8-RXEPb
this.users = users; <4rnOQ:
} p)biOG
{-A|f
/** h'y"`k-
* @param userService yr\ClIU
* The userService to set. 0%%1:W-
*/ ?Q:SVxzUd
publicvoid setUserService(UserService userService){ I`_2Q:r
this.userService = userService; j!+jLm!l
} 1$Hou
} Q4XlYgIV2A
oh5'Isb$
sL@\,]Y
)>@S8v,(
]_C"A
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, Pe`mZCd^
t/ \S9
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 WI\a
@$
7 GrT
么只需要: @=kgK[t
9
java代码: ky2]%cw
)kep:-wm
^ZMbJe%L
<?xml version="1.0"?> rrL.Y&DTK
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork FJn-cR.n
o~$O$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Bx45yaT
suE K;Bk9
1.0.dtd"> Nu7>G
&S4*x|-C&
<xwork> Fk=SkSky
;nSF\X(;{
<package name="user" extends="webwork- y[N0P0r l:
)rEl{a
interceptors"> Y` }X5(A@
@i#JlZM_
<!-- The default interceptor stack name V$ZclV2:Ih
N.*)-O
--> Kq[4I[+R
<default-interceptor-ref kZe<<iv
W&5/1``u\
name="myDefaultWebStack"/> q7 PCMe
O9daeIF0#
<action name="listUser" GDSV:]hL
^E^`"
class="com.adt.action.user.ListUser"> J9lZ1,22
<param 4iA F<|6s
:#:|:q.]
name="page.everyPage">10</param> !E$$FvL
<result n])#<0
Wt/;iq"
name="success">/user/user_list.jsp</result> xn*$Ty+
</action> y#Dh)~|k
oU|G74e6
</package> V'9.l6l
4Y(@
KUb
</xwork> iC3z5_g*@
+2`BZ}5y
PC9,;T&7_
~| j
eNT
Q:b0M11QR
qfsPX6]
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 d,GOP_N8I
"3^tVX%$\[
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 9FDu{4:
vRe{B7}p;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |gE1P/%k
l cl|o3yQ
hDxq9EF
wPg/.N9H
/\%<VBx ?q
我写的一个用于分页的类,用了泛型了,hoho rZ?:$],U!
JpS}X\]i
java代码: zT>!xGTu7~
6*i**
G _cJI
package com.intokr.util; F*P0=DD
^;EhKG
import java.util.List; $Ivjcs:
sZrVANyqb
/** gGMfy]]R
* 用于分页的类<br> 6+$2rS$1V
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -;9
}P
* coAXYn
* @version 0.01 5{'hsC
* @author cheng HoPpUq5,
*/ f3O6&1D
public class Paginator<E> { r *K
privateint count = 0; // 总记录数 !JA;0[;l=
privateint p = 1; // 页编号 Cu7{>"
privateint num = 20; // 每页的记录数 529b. |
privateList<E> results = null; // 结果 = Pv_,%
#I=EYl=Vvi
/**
7IxeSxXH
* 结果总数 "0HUaU,e
*/ L('1NN2
publicint getCount(){ $e+sqgU
return count; 7I;kh`H$(f
} (H_dZL
'?C6P5fm
publicvoid setCount(int count){ 7Bj,{9^aJ
this.count = count; iTHwH{!
} x)C}
j*>J1M3E
/** *?<N3Rr*
* 本结果所在的页码,从1开始 x^K4&'</
* HJ&P[zV^
* @return Returns the pageNo. [oh06_rB
*/ zA5nr`
publicint getP(){ e \Qys<2r
return p; F;Q,cg M
} s!(R
L3{(Bu
/** 2Wzx1_D"a
* if(p<=0) p=1 HTh?&u\QG
* |mtW)
* @param p ZxvH1qx8
*/ es7;eH*O9
publicvoid setP(int p){ 8$NVVw]2,
if(p <= 0)
YNBM\Q
p = 1; `4*I1WZW
this.p = p; :UdW4N-
} _=$~l^Y[
,1ev2T
/** .RpJZ[E
* 每页记录数量 Xmr}$<<=
*/ +0Q
publicint getNum(){ :^y!z1\2(7
return num; lgews"
} WX4sTxJK
^
9+
Qxv
/** v*.R<-X:
* if(num<1) num=1 )=f}vHg$
*/ O?OAXPK2
publicvoid setNum(int num){ ExG(*[l
if(num < 1) |:S6Gp[\O
num = 1; 2}&ERW
this.num = num; 6La[( )
} )|*Qs${tF
d7^
`
/** v_zt$bf{Y
* 获得总页数 q=3>ij{v
*/ c+l1l0BA
publicint getPageNum(){ ZuGSR GX'
return(count - 1) / num + 1; KZ2[.[(Ph
} 3A,N1OXG
WRZpu95v
/** StJb-K/_cL
* 获得本页的开始编号,为 (p-1)*num+1 -`'|z+V
*/ 8;gi8Y
publicint getStart(){ [r`KoHwdm
return(p - 1) * num + 1; +,spC`M6h
} N1'"7eg/
^ = C>
/** O: :FB.k
* @return Returns the results. 4$R!)
*/ [#GBn0BG)
publicList<E> getResults(){ 3uYLA4[-B
return results; l`\L@~l n
} d.f0OhQ
=b%f@x_U1
public void setResults(List<E> results){ s:_hsmc"
this.results = results; x/<ow4C
} mW{;$@PLF"
N[
=I
public String toString(){ w"0$cL3
StringBuilder buff = new StringBuilder br=e+]C Y)
!sX$?P%U
(); |it*w\+M
buff.append("{"); >Cr"q*
buff.append("count:").append(count); q]{gAGe~
buff.append(",p:").append(p); <~mqb=qA$
buff.append(",nump:").append(num); 2xN7lfu1RB
buff.append(",results:").append uL)MbM]
1te^dh:Vp
(results); 7=fM}sk
buff.append("}"); "\*)KH`C
return buff.toString(); Vu(NP\Wm
} 6 :4GI
; Pk"mC
} ZJ{DW4#t
lH3.q4D
5
-=lm`X<: