Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XotiKCk|Aq
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y5@#leM
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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 4Fu:ov
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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 h2S!<
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分页支持类: ;*{"|l qe
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java代码: "mk@p=d
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package com.javaeye.common.util; "FD`1
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import java.util.List; =Ff _)k
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publicclass PaginationSupport { zG\& ZU
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publicfinalstaticint PAGESIZE = 30; kh4., \'
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privateint pageSize = PAGESIZE; fk*I}pDx
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privateList items; {{:QtkN
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privateint totalCount; s78MXS?py
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privateint[] indexes = newint[0]; ]3D>ai?
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privateint startIndex = 0; iY,FfuE
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public PaginationSupport(List items, int NZb}n`:
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totalCount){ %~e+H|
setPageSize(PAGESIZE); Q6 oM$qiM
setTotalCount(totalCount); 0-P,zkK_v
setItems(items); g)Tr#
setStartIndex(0); REg&[e+%
} n[KL Y!
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public PaginationSupport(List items, int OA7YWk<K
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totalCount, int startIndex){ ]Y3NmL
setPageSize(PAGESIZE); 11^.oa+`
setTotalCount(totalCount); H*H~~yQ
setItems(items); MD):g@
setStartIndex(startIndex); @?2ES@G+Ji
} )FdS;]
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public PaginationSupport(List items, int {1eW*9
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totalCount, int pageSize, int startIndex){ |NdWx1
setPageSize(pageSize); Q]{ `m
setTotalCount(totalCount); i7XM7+}
setItems(items); gbrn'NT
setStartIndex(startIndex); BHu%x|d
} 0f5c#/7C9
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publicList getItems(){ rD;R9b"J
return items; C+L_f_6]
} *t{^P*pc
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publicvoid setItems(List items){ #b
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this.items = items; <dGph
} -Hh.8(!XoO
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publicint getPageSize(){ GYt|[GC
return pageSize; )61X,z
} / q| o
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publicvoid setPageSize(int pageSize){ 8B`w!@hf
this.pageSize = pageSize; Fhrj$
} ,p>@:C/M
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publicint getTotalCount(){ hHk9O?
return totalCount; $KVCEe!X
} `%/w0,0
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publicvoid setTotalCount(int totalCount){ K`0'2
if(totalCount > 0){ $(]E$ek
this.totalCount = totalCount; ]7{
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int count = totalCount / bo-L|R&O
n_{az{~
pageSize; `aDVN_h{6
if(totalCount % pageSize > 0) +QEP:#qZw
count++; Q*N{3G!
indexes = newint[count]; R $@$
for(int i = 0; i < count; i++){ "-Yj~
indexes = pageSize * yNhRh>l
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i; mb>8=hMg
} 5uX-onP\[
}else{ W6s-epsRmT
this.totalCount = 0; gW-mXb
} /PKu",Azj
} LC4W?']/
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publicint[] getIndexes(){ &;naaV_2T
return indexes; TT oW>RP#
} 1+#E|YWJ
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publicvoid setIndexes(int[] indexes){ lhPxMMS`j
this.indexes = indexes; +!K*FU=).
} u}.mJDL
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publicint getStartIndex(){ !;U oZ~
return startIndex;
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} >qVSepK3
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publicvoid setStartIndex(int startIndex){ L6"V=^Bq
if(totalCount <= 0) kEp{L
this.startIndex = 0; j[A:So
elseif(startIndex >= totalCount) [:zP]l.|
this.startIndex = indexes ^'n;W<\p)
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[indexes.length - 1]; "Hk7s+%
elseif(startIndex < 0) SZUo RWx
this.startIndex = 0; =6
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else{ z%1& t4$
this.startIndex = indexes 0DFVB%JdI
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[startIndex / pageSize]; [$c"}=g[+
} &`,Y/Cbw
} @*E=O |
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publicint getNextIndex(){ Q
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int nextIndex = getStartIndex() + <.2jQ#So
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pageSize; y'!"GrbZ
if(nextIndex >= totalCount) uvAJJIae'
return getStartIndex(); ?G<ISiABQC
else fB 0X9iV6j
return nextIndex; 6OB3%R'p
} h\2iArw8
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publicint getPreviousIndex(){ 1aZGt2;
int previousIndex = getStartIndex() - D"2bgw
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pageSize; H>Ucmd;ay
if(previousIndex < 0) dUUg}/
return0; +i#s |kKs\
else }>EWFE`
return previousIndex; H:P7G_!\
} M?AKJE j5
qi
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} ^wD`sj<Qg
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抽象业务类 Ss0I{0
java代码: 8 C9ny}
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/** d tE"1nR
* Created on 2005-7-12 NwxDxIIH/)
*/ S>)[n]f
package com.javaeye.common.business; %WC^aKfY
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import java.io.Serializable; 2m"cK^
import java.util.List; do*aE
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import org.hibernate.Criteria; ?bpVdm!
import org.hibernate.HibernateException; G8 q<)
import org.hibernate.Session; Uu52uR
import org.hibernate.criterion.DetachedCriteria; M[+#*f.T}
import org.hibernate.criterion.Projections; m\XG7uo~
import hzU(XW
.
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org.springframework.orm.hibernate3.HibernateCallback; =ZO lE|4
import ]1pB7XL
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org.springframework.orm.hibernate3.support.HibernateDaoS t-5Y,}j
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upport; ~L>86/hP,N
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import com.javaeye.common.util.PaginationSupport; 6^!fuIZ;_
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public abstract class AbstractManager extends c-v-UO%
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HibernateDaoSupport { hsT&c|
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privateboolean cacheQueries = false; ?z <-Ww
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privateString queryCacheRegion; "Zx<hL*
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publicvoid setCacheQueries(boolean 9UVT]acq
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cacheQueries){ 1;DRcVyS+
this.cacheQueries = cacheQueries; V#b=mp
} B^]PKjLNZ
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publicvoid setQueryCacheRegion(String H
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queryCacheRegion){ ~
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this.queryCacheRegion = ?Pa(e)8\
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queryCacheRegion; 'n
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} =*I|z+
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publicvoid save(finalObject entity){ 3kk^hvB+f
getHibernateTemplate().save(entity); Ibu9AwPm
} {~uTi>U
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publicvoid persist(finalObject entity){ b$%Kv(
getHibernateTemplate().save(entity); E4>}O;m0
} qv}ECQ
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publicvoid update(finalObject entity){ ><Zu+HX
getHibernateTemplate().update(entity); q5L^>"
} ."=%]l0
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publicvoid delete(finalObject entity){ la)^`STh
getHibernateTemplate().delete(entity); AS@(]T#R
} 2%L`b"9}V
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publicObject load(finalClass entity, )XGz#C_P
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finalSerializable id){ =*jFaj
return getHibernateTemplate().load ""XAUxo
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(entity, id); eBs.RR
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}
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publicObject get(finalClass entity, R ZQH#+*t}
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finalSerializable id){ j6Sg~nRh
return getHibernateTemplate().get M?UUT8,
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(entity, id); <n 06(9BF
} @+H0D"
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publicList findAll(finalClass entity){ T'vI@i9
return getHibernateTemplate().find("from c9fz x
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" + entity.getName()); RJzIzv99m
} kHylg{i{"
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publicList findByNamedQuery(finalString \20}/&
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namedQuery){ GT)7VF rL
return getHibernateTemplate @$n
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().findByNamedQuery(namedQuery); `6J7c;:
} X,_K
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publicList findByNamedQuery(finalString query, c6#E gN,X
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finalObject parameter){ U|x Hy+N
return getHibernateTemplate D|*w6p("z
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().findByNamedQuery(query, parameter); 5;HGS{`
} v-d"dC`
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publicList findByNamedQuery(finalString query, ){w{#
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finalObject[] parameters){ -5+Yz9pv[
return getHibernateTemplate B K+P
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().findByNamedQuery(query, parameters); i79$D:PcLa
} *oz#YGNm
2#R$-*;#
publicList find(finalString query){ a-Y6ghs
return getHibernateTemplate().find _!qD/[/
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(query); >Ti%Th,
} J(d[05x0
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publicList find(finalString query, finalObject a;Y:UwD9*
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parameter){ 1Ub=RyB
return getHibernateTemplate().find k}H7bZug
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(query, parameter); '~K]=JP
} KFHZ3HZ:>
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public PaginationSupport findPageByCriteria =3QhGFd
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(final DetachedCriteria detachedCriteria){ ub-e! {
return findPageByCriteria D^6iQW+.P
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); V~j^
} OxGfLeP.R!
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public PaginationSupport findPageByCriteria 1b3k|s4
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(final DetachedCriteria detachedCriteria, finalint \DS*G7.A+&
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startIndex){ SDO:Gma
return findPageByCriteria 'LPyh ;!f
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(detachedCriteria, PaginationSupport.PAGESIZE, (9I(e^@]
F +(S-Qk1
startIndex); [BD`h
} ZAn @NA=
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public PaginationSupport findPageByCriteria 7WS$fUBi
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(final DetachedCriteria detachedCriteria, finalint re[5lFQ~Z
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pageSize, }k-8PG =
finalint startIndex){ XdCP!iq*8
return(PaginationSupport) E#:!&{O
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getHibernateTemplate().execute(new HibernateCallback(){ /Tm+&Jd
publicObject doInHibernate ?[zw5fUDS
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(Session session)throws HibernateException { InbB2l4G
Criteria criteria = UzaAL9k
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detachedCriteria.getExecutableCriteria(session); M9R'ONYAa
int totalCount = ~:7y!=8#
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1
((Integer) criteria.setProjection(Projections.rowCount ub~ t}
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()).uniqueResult()).intValue(); z~vcwiYAP
criteria.setProjection 27ZqdHd
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(null); Zw0KV%7hD
List items = ]dNNw`1\V
9h\RXVk{tA
criteria.setFirstResult(startIndex).setMaxResults Jk>vn+q8P^
T.;{f{
(pageSize).list(); ["Ts7;q9[
PaginationSupport ps = {Z8GG
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new PaginationSupport(items, totalCount, pageSize, /}~=)QHH
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startIndex); 3W[?D8yi)
return ps; D
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} a)pc+w#
}, true); mbkt7. ,P
} /Z:NoTGn
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public List findAllByCriteria(final w6!97x
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DetachedCriteria detachedCriteria){ uthW
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return(List) getHibernateTemplate r+C4<-dT
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().execute(new HibernateCallback(){ Fnak:R0
publicObject doInHibernate Ez|NQ:o
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(Session session)throws HibernateException { *4%pXm;
Criteria criteria = EOu[X'gLr
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detachedCriteria.getExecutableCriteria(session); q`r| DcN~
return criteria.list(); 4Z%1eOR9V
} /A,w{09G
}, true); rIFW1`N}i
} b-VtQ%Q
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public int getCountByCriteria(final K9Mz4K_
@z ",1^I
DetachedCriteria detachedCriteria){ #tu>h
Integer count = (Integer) d~~, 5E
} uS0N$4
getHibernateTemplate().execute(new HibernateCallback(){ N!~]D[D
publicObject doInHibernate ;]grbqXVE
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(Session session)throws HibernateException { Pp!4Ak4TT9
Criteria criteria = ZtO$kK%q;
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detachedCriteria.getExecutableCriteria(session); e7"T37
return pTq DPU
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criteria.setProjection(Projections.rowCount J/e]
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()).uniqueResult(); "!zJQl@
} [yN+(^i
}, true); WC<[<uI*
return count.intValue(); W=^.s>7G
} wl]3g
} gQ0,KYmI3_
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2
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用户在web层构造查询条件detachedCriteria,和可选的 +U<YM94?
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 g=nb-A{#
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PaginationSupport的实例ps。 uFSU|SDd.
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ps.getItems()得到已分页好的结果集 _x(hlHFk
ps.getIndexes()得到分页索引的数组 $Okmurnn
ps.getTotalCount()得到总结果数 .5a>!B.I
ps.getStartIndex()当前分页索引 _2G _Io
ps.getNextIndex()下一页索引 hJ ^+asr
ps.getPreviousIndex()上一页索引 b]z_2h~`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r craf4%
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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 @ywtL8"1~
/gF)msUF
一下代码重构了。 /xJD/"Y3&
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我把原本我的做法也提供出来供大家讨论吧: &6OY^6<
af |mk@
首先,为了实现分页查询,我封装了一个Page类: 6k;5T
java代码: 6vbKKn`ST
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/*Created on 2005-4-14*/ X<8|uP4
package org.flyware.util.page; I ==)a6^
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/** +Xw%X3o)
* @author Joa zs]ubJC@
* >&;J/ME
*/ ]'Eg2(wy
publicclass Page { zGU MH7 M
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/** imply if the page has previous page */ iT==aJ=~/&
privateboolean hasPrePage; V WZpEi
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/** imply if the page has next page */ I"czo9Yspd
privateboolean hasNextPage; W8^A{l4
ho{%7\
/** the number of every page */ neM)(` gp
privateint everyPage; G 0pq'7B
:Y /aT[
/** the total page number */ H( .9tuA
privateint totalPage; udUc&pX
|MGT8C&^!
/** the number of current page */ #1$4<o#M
privateint currentPage; M5:.\0_
3Ed
/** the begin index of the records by the current eGQ4aQhi
q-Z<.GTq
query */ m-uXQS^@G
privateint beginIndex; Vc9Bg2f5
":+d7xR?o
</_QldL_
/** The default constructor */ ,H6P%
public Page(){ zNo,PERG
@Ik5BT
} o`Z3}
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/** construct the page by everyPage Vn5%%?]J
* @param everyPage yT OZa-
* */ ib(|}7Je
public Page(int everyPage){ bgE]Wk0
this.everyPage = everyPage; 0o$RvxJ
} 0(+<uo~6p1
m33&obSP
/** The whole constructor */ i5le0lM
public Page(boolean hasPrePage, boolean hasNextPage, JmCHwyUK?
?0X$ox
@Un/,-ck
int everyPage, int totalPage, Ue Ci{W
int currentPage, int beginIndex){ !%R):^R8
this.hasPrePage = hasPrePage; %_:L_VD@
this.hasNextPage = hasNextPage; 19GF%+L
,
this.everyPage = everyPage; <$?#P#A
this.totalPage = totalPage; sT1OAK\^
this.currentPage = currentPage; U3Gg:onuE
this.beginIndex = beginIndex; [\Wl~
a l
} I_f%%N%
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/** fsOlg9
* @return PtuRXx
* Returns the beginIndex. BDfMFH[1
*/ X_X7fRC0
publicint getBeginIndex(){ gHp4q!SJ7
return beginIndex; yx?oxDJg
} :K~@JlJd
R-pON4D"*
/** 1d49&-N
* @param beginIndex <FkaH8,7
* The beginIndex to set. n5~Dxk
*/ PYi<iSr
publicvoid setBeginIndex(int beginIndex){ ,s%+vD$O^
this.beginIndex = beginIndex; RvA "ug.*
} 2d|^$$#`
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/** 2UYtEJ(?`{
* @return `_LQs9J0J
* Returns the currentPage. X n0HJ^"_
*/ xp:I(
publicint getCurrentPage(){ z<t2yh(DF
return currentPage; uHquJQ4
} YYI0iM>
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/** v,Kum<oi?
* @param currentPage ]+ub
R;
* The currentPage to set. 1^NC=IS9z
*/ 6%t6u3
publicvoid setCurrentPage(int currentPage){ [YlRz
this.currentPage = currentPage; $ H@
} oAN,_1v)
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/** EK>x\]O%T
* @return `>KNa"b%$
* Returns the everyPage. &'e+`\
*/ aO |@w"p8
publicint getEveryPage(){ =4x6v<
return everyPage; uh9b!8
} V
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z I9jxwXU
/** ysp,:)-%G@
* @param everyPage fMf;
* The everyPage to set. s3ASA.*
*/ bp8sZK"z
publicvoid setEveryPage(int everyPage){ dh{py
this.everyPage = everyPage; Da! fwth
} !|VtI$I>x
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/** s$f9?(,.Ay
* @return 5R.jhYAj
* Returns the hasNextPage. #%GBopv
*/ kQ\l7xd
publicboolean getHasNextPage(){ )qX.!&|I
return hasNextPage; lgt&kdc%o
} &9v8
Q!-"5PX
/** yWc%z6dXC
* @param hasNextPage Pt-mLINvG
* The hasNextPage to set. :k_)Bh?+
*/ N>L)2WKFT
publicvoid setHasNextPage(boolean hasNextPage){ )=glN<*?
this.hasNextPage = hasNextPage; ?:GrM!kq76
} zBI2cB8;P
R^@`]dX$
/** p `oB._
R
* @return ,lCFe0>k!=
* Returns the hasPrePage. +c]D2@ctG
*/ S~z$=IiB
publicboolean getHasPrePage(){ Y -BZV |
return hasPrePage; K vPLA{
} H^B,b!5i
xV`)?hEXFh
/** -{?xl*D
* @param hasPrePage "{S4YA
* The hasPrePage to set. kSge4?&
*/ !eb{#9S*
publicvoid setHasPrePage(boolean hasPrePage){ \l[AD-CZPh
this.hasPrePage = hasPrePage; N-}OmcO]e
} XkW@"pf&Fh
@/01MBs;
/** b<r*EY
* @return Returns the totalPage. [r]<~$
* 8j]QnH0&
*/ C2iOF /4
publicint getTotalPage(){ m=pH G
return totalPage; RAEN
&M
} ept:<!4
{9@E[bWp#
/** DB jUHirK
* @param totalPage \Ff]}4
* The totalPage to set. ]=|iO~WN
*/ `N7erM
publicvoid setTotalPage(int totalPage){ &8%^o9sH
this.totalPage = totalPage; Iw$T'I+4W
} w3fD6$
Uq%|v
} "$"<AKCwS
x )q$.u+
~Wm'~y>
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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 Br$/hn=
'/ueY#eG
个PageUtil,负责对Page对象进行构造: x1CMW`F
java代码: 4^6Oh#p0
>Zf*u;/dW$
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/*Created on 2005-4-14*/ q{yzux
package org.flyware.util.page; gs@^u#O
z;0]T=g
import org.apache.commons.logging.Log; [ifQLsHA
import org.apache.commons.logging.LogFactory; 4g.S!-H@R
S[rfcL"
/** ?K.!^G
* @author Joa 1Ji"z>H*
* at3YL[,[Z
*/ Uzn
publicclass PageUtil { eLyIQo W
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privatestaticfinal Log logger = LogFactory.getLog jd+HIR
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(PageUtil.class); 9I|Q`j?p`
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/** Oo\~'I
* Use the origin page to create a new page giN(wPgYP
* @param page LR17ilaa'
* @param totalRecords @[rlwwG,
* @return [9p@uRE
*/ mL,{ZL ^
publicstatic Page createPage(Page page, int l4^8$@;s
NXE1v~9V
totalRecords){ "yXqf%CGE
return createPage(page.getEveryPage(), Y}x_ud,
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page.getCurrentPage(), totalRecords); okW'}@jD
} Pb :6nH=
=gB{(
/** ~1{~iB2G
* the basic page utils not including exception ~#zb
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handler Y7yzM1?t
* @param everyPage @qsOWx`l$
* @param currentPage ^A;ec
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* @param totalRecords y|.dM.9V
* @return page A<g5:\3
*/ `,wX&@sN
publicstatic Page createPage(int everyPage, int l%xeM!}
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currentPage, int totalRecords){ Au?(_*/0
everyPage = getEveryPage(everyPage); l}Vg;"1'J
currentPage = getCurrentPage(currentPage); gE!`9 #..
int beginIndex = getBeginIndex(everyPage, 5YiBw|Z7 "
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currentPage); "\1V^2kMr
int totalPage = getTotalPage(everyPage, yj`xOncE}
C_hIPMU=
totalRecords); odq3@
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boolean hasNextPage = hasNextPage(currentPage, l_=kW!l
<gr2k8m6$
totalPage); m9m~ 2
boolean hasPrePage = hasPrePage(currentPage); h1?.x
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returnnew Page(hasPrePage, hasNextPage, n~&e>_;(.
everyPage, totalPage, \cq.M/p
currentPage, q/YO5>s15
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beginIndex); o Bp.|8-
} 5 s2/YG=
e-o$bf%
privatestaticint getEveryPage(int everyPage){ !]WC~#|{B
return everyPage == 0 ? 10 : everyPage; 4>[tjz.?k
} B.[5N;c
["?WVXCF8|
privatestaticint getCurrentPage(int currentPage){ QnDLSMx)
return currentPage == 0 ? 1 : currentPage; fm,:8%
} V=H}Ecd
`_+m3vHG
privatestaticint getBeginIndex(int everyPage, int O Bp/:]
%O&C\{J
currentPage){ p$%g$K
return(currentPage - 1) * everyPage;
PYYO-Twg
} _:;j)J0
-
e"XEot~
privatestaticint getTotalPage(int everyPage, int 1HNX6
z0&I>PG^
totalRecords){ ]r1C
int totalPage = 0; W.U|mNJ$
\~q cYp
if(totalRecords % everyPage == 0) o!t1EPJE*
totalPage = totalRecords / everyPage; -wV0Nv(V8
else 38q0iAH
totalPage = totalRecords / everyPage + 1 ; 'r?OzFtxh
[ w1"
return totalPage; \8X8NCM
} (vf5qF^
1]XIF?_Dm
privatestaticboolean hasPrePage(int currentPage){ c'6$`nC
return currentPage == 1 ? false : true; F1o"H/:n
} ?rH=< #@
> 'KQL?!F
privatestaticboolean hasNextPage(int currentPage, >pl*2M&
oE4hGt5x{
int totalPage){ _A/ ]m4
return currentPage == totalPage || totalPage == :WnXoL
|tS~\_O/
0 ? false : true; cB[.ET$
} 4)nQBFX
/L"&'~
;42D+q=s
} ;w}5:3+
w]0jq
U6
gBG.3\[
Uyyw'Ni
k||DcwO
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。 +#<"o#gZ
RsDI7v
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 #8d$%F))
p{Gg,.f!HM
做法如下: wbId}!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 WH$
Ls('
oYN# T=Xi
的信息,和一个结果集List: 62LQUl]<
java代码: *ha9Vq@X
$bKa"T*
Fw5r\J87c
/*Created on 2005-6-13*/ K\ \UF
package com.adt.bo; [0e]zyB+
M O/-?@w
import java.util.List; CQ3{'"b
w65
$ R
import org.flyware.util.page.Page; i=<(fq
h(G(U_V-Od
/** ~qT+sc!t
* @author Joa
'[#uf/~W
*/ P5P<-T{-c
publicclass Result { n1W}h@>8
:r/rByd'
private Page page; ;"nEEe]?
HnqZ7%jeN
private List content; U-s6h;^O
3^us;aOr
/** qO9_e
* The default constructor o&~z8/?LA
*/ wEMUr0Hq
public Result(){ c(AjM9s
super(); &4DV]9+g
} V*'9yk"
E|Grk
/** `czXjZE
* The constructor using fields L4;n$=e
* d*,|?Ar*b
* @param page VuZmX1x)N
* @param content Ck.GN<#-^P
*/ (|5g`JDG
public Result(Page page, List content){ I$wP`gQh
this.page = page; _bks*.9}3b
this.content = content; Gf'V68,l$
} xI~\15PhG
uj/le0
/** ZcO!cR&*'J
* @return Returns the content. hoeTJ/;dm
*/ R/O_*XY
publicList getContent(){ 1ck2Gxn
return content; W^+bgg<.
} =8dCk\/
R4JO)<'K&
/** qW<: `y
* @return Returns the page. {YbqB6zaM
*/ M3F8@|2
public Page getPage(){ a<gzI
return page; n(f&uV_):
} 9au)K!hN
s_Dl8O4u
/** i]$7w! r&
* @param content 65J'uN
* The content to set. 6U+#ADo
*/ G%kXr$?W
public void setContent(List content){ ?0;b}Xl-
this.content = content; ?I/,r2ODLh
} c@q>5fR/c
l2`8]Qr
/** T)Nis~
* @param page 9 [I ro
* The page to set. #t(?8!F
*/ a*IJ)'S
publicvoid setPage(Page page){ G(0bulq
this.page = page; ld@f:Zali
} _Wb-&6{
} v*BA\&
P7y[9|^
!s)$_tG
X}usyO'pW
)sS<%Xf
2. 编写业务逻辑接口,并实现它(UserManager, Jc%>=`f
&&<^wtznO
UserManagerImpl) !J6s^um
java代码: CWN=6(y
Y+=@5+G
(wY%$kW4
/*Created on 2005-7-15*/ gCm?nb)
package com.adt.service; 7e=a D~f
\qTn"1bQ
import net.sf.hibernate.HibernateException; YHRI U Yd
&'](T9kg=
import org.flyware.util.page.Page; Nm081ic2<
4*9Dh
import com.adt.bo.Result; F#<PFT4i
.$OInh
/** 1)PR]s:-m@
* @author Joa r?+u}uH
*/ /Bwea];^Q
publicinterface UserManager {
8DI|+`OgW
R$3JbR.
public Result listUser(Page page)throws p.}[!!m P
p4AXQuOP
HibernateException; e-K 8K+7
oF6MV&q/
} D&^:hs@
EqmJXDm
BxT~1SBFq
UQdQtj1'
Cg|uHI*
java代码: 88*RlxU
yR$_$N+E
( gFA? aD<
/*Created on 2005-7-15*/ &sNID4FR
package com.adt.service.impl; Vl z T
`x#~-
import java.util.List; GSFT(XX
s+w<!`-
import net.sf.hibernate.HibernateException; Y'HF^jv]R
N*MR6~z4
import org.flyware.util.page.Page; 0* "j:V
import org.flyware.util.page.PageUtil; =dw1Q
AP7W)S
import com.adt.bo.Result; R`?^%1^N
import com.adt.dao.UserDAO; lKD@2
import com.adt.exception.ObjectNotFoundException; Uy1xNb/d
import com.adt.service.UserManager; [O)Zof
;VH]TKkk
/** jlP7'xt1%
* @author Joa ,qHG1#^
*/ ).S<{zm7
publicclass UserManagerImpl implements UserManager {
_NZHrN
:58'U|
private UserDAO userDAO; ]VH@\
f
WuQYEbap
/** X]*/]Xx
* @param userDAO The userDAO to set. (j I|F-i
*/ yy74>K
publicvoid setUserDAO(UserDAO userDAO){ 3d<HIG^W}
this.userDAO = userDAO; H44&u](8{
} |G@)B!>
3,5wWT]
)
/* (non-Javadoc) N9PM.nbd%
* @see com.adt.service.UserManager#listUser Iz8^?>X
!U!E_D.O
(org.flyware.util.page.Page) 2"'8x?.V
*/ Cr%r<*s
public Result listUser(Page page)throws Os!22 O
;$E[u)l
HibernateException, ObjectNotFoundException { M(E_5@?3
int totalRecords = userDAO.getUserCount(); *Kkw,qp/
if(totalRecords == 0) t5APD?5 c
throw new ObjectNotFoundException "3MUrIsB>
4<K`yU]"
("userNotExist");
*4:/<wI!
page = PageUtil.createPage(page, totalRecords); xwxj j
List users = userDAO.getUserByPage(page); h3IkOh4|h
returnnew Result(page, users); `4q}D-'TF8
} kZ}u
<^_?hN8.
} @]tGfr;le&
15:@pq\
"6.p=te
$I36>
yy1r,dw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <3x#(ms!!
Lx{N%;t*E
询,接下来编写UserDAO的代码: z\Y^x9
3. UserDAO 和 UserDAOImpl: F.5b|&@
java代码: hNo>)$v!s
IR8&4qOs
mO>
M=2A
/*Created on 2005-7-15*/ +|<b0Xd
package com.adt.dao; aF"Z!HD
Hc%\9{zH
import java.util.List; =M#?* e
-b}S3<15@
import org.flyware.util.page.Page; X4G55]D$>
05 Q8`
import net.sf.hibernate.HibernateException; y;Ln ao7i
pe%)G6@G
/** Ur(o&,
* @author Joa .6F3;bg R7
*/ U3K<@r
publicinterface UserDAO extends BaseDAO { h}>/Z3*
=hOa
0X=
publicList getUserByName(String name)throws ZC*d^n]x.
3a}`xCO5
HibernateException; mZVOf~9E
51ebE`
publicint getUserCount()throws HibernateException; U(=9&c@]
PjW+V`
publicList getUserByPage(Page page)throws c\{}FGC
C'2 =0oou
HibernateException; 97wy;'J[u
~+ wamX3
} g
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hr6e 1Er
2\\3<
@h$0S+?:
[(F<|f:n
java代码: dd7nO
:]
F'$S!K58
4`P2FnJ?
/*Created on 2005-7-15*/ O)JUY*&I5
package com.adt.dao.impl; EJ ~kZ3
,wi=!KzX
import java.util.List; 9PqgBq
U"Hquo
import org.flyware.util.page.Page; \u-e\w
PbHh?iH
import net.sf.hibernate.HibernateException; M .`
import net.sf.hibernate.Query; K!c@aD:#
|kNGpwpI
import com.adt.dao.UserDAO; ls7A5 <
U.7y8#qf3R
/** [ky6E*dV`
* @author Joa {3(.c, q@
*/ Z;~[@7`
public class UserDAOImpl extends BaseDAOHibernateImpl 9Y%?)t.2
E5BgQ5'
implements UserDAO { 'b?.\Bm;
|z]2KjF&w-
/* (non-Javadoc) :t{vgi D9
* @see com.adt.dao.UserDAO#getUserByName )USC
]z=Vc#+!
(java.lang.String) ?g;ZbD
*/ 3!9 yuf
publicList getUserByName(String name)throws n`z+ w*
&:CjUaP@
HibernateException { k-pEBhOH
String querySentence = "FROM user in class u1{ym_
Y0B1xL@
com.adt.po.User WHERE user.name=:name"; m?VRX.>
Query query = getSession().createQuery m_"p$m;
9N
D+w6"
(querySentence);
2ZG1n#
query.setParameter("name", name); _|
return query.list(); -+=:+LhSMb
} ,;iBeqr5
@fH&(@
/* (non-Javadoc) c\MsVH2|
* @see com.adt.dao.UserDAO#getUserCount() A$%!9Cma
*/ CTkN8{2S
publicint getUserCount()throws HibernateException { ki~y@@3I
int count = 0; \}x'>6zr2
String querySentence = "SELECT count(*) FROM ff}a <w
+e8>?dkq
user in class com.adt.po.User"; LJ(n?/z%
Query query = getSession().createQuery 6=,#9C9
CFJjh^
~=
(querySentence); ^[,s_34V
count = ((Integer)query.iterate().next ~x4B/zW?
oCKM5AVWsv
()).intValue(); Hg9.<|+yo
return count; <@e+-$
} |[37:m
p + l_MB
/* (non-Javadoc) C. Ja;RFq
* @see com.adt.dao.UserDAO#getUserByPage O GFE*
~`\9Q
(org.flyware.util.page.Page) xe6_RO%
*/ E! I
publicList getUserByPage(Page page)throws 1n`1o-&l-
a}Fk x
HibernateException { pH\^1xj
=
String querySentence = "FROM user in class zd9]qo
inB PT~y
com.adt.po.User"; &=-e`=qJ'6
Query query = getSession().createQuery ]`@]<6
*F
szGn<
(querySentence); r6n5 Jz
query.setFirstResult(page.getBeginIndex()) "@{4.v^}!
.setMaxResults(page.getEveryPage()); T")i+v
return query.list(); pYfV~Q^3
} IypWVr
Vj=Xcn#*8
} fi&uB9hc
c3V]'~
!2Y!jz
?]W~ qgA
kPO6gdwq$
至此,一个完整的分页程序完成。前台的只需要调用 _3.G\/>[K
p/hvQyE
userManager.listUser(page)即可得到一个Page对象和结果集对象 |0L=8~M(j
e?!L}^f6X
的综合体,而传入的参数page对象则可以由前台传入,如果用 w#xeua|*I#
7<3U? ]0
webwork,甚至可以直接在配置文件中指定。 z+k=|RMau
,!I?)hwOC
下面给出一个webwork调用示例: p?V?nCv1O
java代码: 9fNu?dE
Ak6MPuBB-
+mc[S
/*Created on 2005-6-17*/ {Z#e{~m#
package com.adt.action.user; >I4p9y(u
^XBzZ!h|
import java.util.List; 4bi NGl~
zj>aaY
import org.apache.commons.logging.Log; h`5YA89
import org.apache.commons.logging.LogFactory; [0&'cu>
import org.flyware.util.page.Page; M@~~f
_%'L@[ H
import com.adt.bo.Result; eyT>wma0
import com.adt.service.UserService; PFS;/
import com.opensymphony.xwork.Action; x6^l6 N
tlV &eN
/** D0/DI
* @author Joa veUa|Bx.(v
*/ J3e:Y!
publicclass ListUser implementsAction{ /2;dH]o0
]cm6 |`pz
privatestaticfinal Log logger = LogFactory.getLog Xnv@H:$mxk
(#6AKr9K
(ListUser.class); &~~aAg
`KpFH.k.K
private UserService userService; c~}={4M]
oZvA~]x9\
private Page page;
76-jMcGi
{~bIA!kAFI
privateList users; 0n:?sFY>
?;|@T ty%
/* b!0DH[XKV
* (non-Javadoc) O' +"d%2'
* Q2/MnM
* @see com.opensymphony.xwork.Action#execute() L[?nST18%
*/ Kt
W6AZJ
publicString execute()throwsException{ {p`mfEE(
Result result = userService.listUser(page); q,B3ru.?d
page = result.getPage(); e>l,(ql
users = result.getContent(); i:o}!RZ>
return SUCCESS; ZFS7{:
} nbI=r+
A4G,}r *n
/** `)R?nVb
* @return Returns the page. AF^T~?t
*/ RU2c*q$^X
public Page getPage(){ xvU]jl6d
return page; d0(Cn}m"c
} mxQR4"]jY
Q>.BQ;q]
/** ^P`NMSw
* @return Returns the users. wV\%R,bZj
*/ iF!mV5#
publicList getUsers(){ P|e`^Frxt
return users; pDu{e>S|:
} *AZ?~ i^o
v`JF\"}S
/** R7K!A
%
* @param page .xO
_E1Ku;
* The page to set. !;%y$$gxh
*/ /XcDYMKgh
publicvoid setPage(Page page){ dY} pN"
this.page = page; H@{Objh1
} 4j>fI)FUW
lT]=&m>
/** ;UYc
* @param users `} =yG_!A
* The users to set. g\Wj+el}
*/ 9UwLF`XM
publicvoid setUsers(List users){ #G_F`&
this.users = users; Sw)i1S9
} F|9+ +)
Bv$UFTz
/** ;7Y[c}V1^
* @param userService jM~Bu.7 i6
* The userService to set. TyF{tuF
*/ 2i\Q@h
publicvoid setUserService(UserService userService){ 17}$=#SX
this.userService = userService; l&Z
Sm
} =SAV|
} dpwD8Q<
U
\m4T3fy
'-vE%U@<
#'@ilk/.
mOP4z'
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, f~=r*&U
X7aYpt;
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 3HZ~.
J~KX|QY.S
么只需要: jd 1jG2=f
java代码: %j7:tf=
k=[pm5ZvT~
I"@p aLZ
<?xml version="1.0"?> q"akrI38
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ['cz;2{:W
4KXc~eF[M"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- %-+j
GIT#<+"
1.0.dtd"> IG< H"tQ
J8?2R^;{
<xwork> !\-WEQrp\
>"v9iT
<package name="user" extends="webwork- pMR,#[U<
a(;!O}3_)(
interceptors"> {uU 2)5i2-
$ rUSKm#
<!-- The default interceptor stack name ACg;CTBb
prtK:eGe2
--> 03=5Nof1
<default-interceptor-ref ?]#OM_,8
3J~0O2
name="myDefaultWebStack"/> W@.Ji B
j8++R&1f]
<action name="listUser" f'X9HU{Cz
.oqIZ\iik
class="com.adt.action.user.ListUser"> hmpr%(c `
<param 5.vG^T0w
,:)`+v<
name="page.everyPage">10</param> 1!1!PA9u
<result ZF6c{~D
1@>$ Gcc
name="success">/user/user_list.jsp</result> 0K`[,$Y
</action> 9CJ(Z+;OM
+5!&E7bcd
</package> {u"8[@@./
:@eHX&
</xwork> H4:&%"j7
s$w;q\1z
LlHa5]E@6
aJhxc<"e
7I9aG.;
^{F_a
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 :z&7W<
8|@9{
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。 e(?]SU|
=2Cj,[$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 wM~H(=s`D
wi_'iv
SmhGZ
5'KA'>@
aUc|V{Jp
我写的一个用于分页的类,用了泛型了,hoho /( hUfYm0
iEm ?
java代码: E5</h"1
u
8^{
SJ?cI!=x
package com.intokr.util;
=-"c*^$]
jQS 6J+F]
import java.util.List; ) ;FS7R
]p7jhd=
/** T/pqSmVpM
* 用于分页的类<br> j8Cho5C
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 15U (={
* ,ho3
* @version 0.01 c!#:E`
* @author cheng 5T@aCC@$h
*/ ?QZ"JX])
public class Paginator<E> { E&`Nh5 JfC
privateint count = 0; // 总记录数 ]e'fa/I
privateint p = 1; // 页编号 JH8}Ru%Z
privateint num = 20; // 每页的记录数 l{Dct\ #s
privateList<E> results = null; // 结果 K2{aNvR)t
:9|\Z|S(I
/** _oG&OJ@
* 结果总数 bq>_qpr
*/ =K\r-'V
publicint getCount(){ *=AqM14 @
return count; bD^b
} ;G\8jP'
zZ=pP5y8
publicvoid setCount(int count){ #P<N^[m
this.count = count; Hnk:K9u.B:
} -fS.9+k0/
EV pi^>M
/** #|[
M?3
* 本结果所在的页码,从1开始 6eFp8bANN#
* ^r6!l.
* @return Returns the pageNo. ;&V s4
*/ >J9oH=S6
publicint getP(){ }e2VY
return p; vS\Nd1~ ?
} SAYLG
+{<#(}
/** ^ D%FX!$
* if(p<=0) p=1 ziPR>iz-
* YNwp/Y
* @param p km~Ll
*/ bKg8rK u
publicvoid setP(int p){ 2i;7{7
if(p <= 0) :cB=SYcC%
p = 1; oVFnlA
this.p = p; ;oZ)Wt
} %D$]VSP;
0:w"M<80
/** eET&pP3Rp
* 每页记录数量 AIMSX]m
*/ a=cvCf
publicint getNum(){ Ar*^;/
return num; jTO),
v:w
} b 5yW_Ozdh
hj'(*ND7z
/** CI353-`
* if(num<1) num=1 MZ+^-@X
*/ ls@i".[
publicvoid setNum(int num){ *Kdda}
J+
if(num < 1) p
sL?Y
num = 1; #(An6itl
this.num = num; IxLhU45
} O nQdq^UB
.7K7h^*F
/** `]Q:-h
* 获得总页数 'AN>`\mR$
*/ =[b)1FUp
publicint getPageNum(){ RuII!}*
return(count - 1) / num + 1; (x/k.&
} X 1
57$
okbQ<{9
/** [!!Q,S"
* 获得本页的开始编号,为 (p-1)*num+1 rj(T~d4
*/ }gJ (DbnV
publicint getStart(){ 93Co}@Y;Y+
return(p - 1) * num + 1; h1'\:N`
} pe^u$YE
ns6(cJ^a
/** Fu!RhsW5j
* @return Returns the results. J8mdoVt
*/ SkmT`*v@
publicList<E> getResults(){ dFKM
8_jH
return results; ^0/j0]O
} ;L']e"G
ZK>WW
public void setResults(List<E> results){ 0PlO(",a
this.results = results; w!fE;H8w6
} |PC*=ykT3
j~!X;PV3
public String toString(){ ~l)-wNqR4r
StringBuilder buff = new StringBuilder J0@X<Lt U
Q~Hy%M%R3
(); @Y1s$,=xB
buff.append("{"); l1f\=G?tmU
buff.append("count:").append(count); O)[1x4U
buff.append(",p:").append(p); vM5k_D
buff.append(",nump:").append(num); 8ji_#og
buff.append(",results:").append y3fGWa*7e
U&?v:&c#&n
(results); Ytl4kaYS
buff.append("}"); EOCN&_Z;
return buff.toString(); 6oGYnu;UZ
} Uu `9"
Mnscb
} gP;&e:/3
Q)IKOt;N]
xL\0B,]