Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 OH 13@k
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4"pU\g
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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 6HZVBZhM
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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 3T/&T`T+c
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分页支持类: X"sJiF S
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java代码: [V_+/[AA)
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package com.javaeye.common.util; ";;!c. !^
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import java.util.List; &smZ;yb|'h
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publicclass PaginationSupport { ~)VI`36X
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publicfinalstaticint PAGESIZE = 30; [FZq'E"87
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privateint pageSize = PAGESIZE; w"37sv
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privateList items; I1#MS4;$^
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privateint totalCount; ^wD`sj<Qg
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privateint[] indexes = newint[0]; S503b*pM
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privateint startIndex = 0; 7xFZJ#
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public PaginationSupport(List items, int ~N2=44e
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totalCount){ [k0/ZfFwV
setPageSize(PAGESIZE); uQ&> Wk
setTotalCount(totalCount); 1=,y+Xpw
setItems(items); hzU(XW
setStartIndex(0); E*IP#:R
} (tX)r4VU
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public PaginationSupport(List items, int <s7cCpUFP
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totalCount, int startIndex){ C,A/29R,s
setPageSize(PAGESIZE); a4gX@&it_k
setTotalCount(totalCount); +KD7Di91<K
setItems(items); rL&Mq}7QK
setStartIndex(startIndex); 9UVT]acq
} nM Z)x-
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public PaginationSupport(List items, int 2gZ nrU
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totalCount, int pageSize, int startIndex){ s2GF*{
setPageSize(pageSize); r/HCWs|
setTotalCount(totalCount); (Zd(?">i
setItems(items); f0j]!g
setStartIndex(startIndex); pkae91
} dgIH`<U$
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publicList getItems(){ U4^c{KWS
return items; f$6N
} xb<|m2<)H
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publicvoid setItems(List items){ gua7<z6=eh
this.items = items; 1+WVh7gF
} tpC^68*F
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publicint getPageSize(){ aK95&Jyw&
return pageSize; S2;^
} 80_w_i +
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publicvoid setPageSize(int pageSize){ 5h`L W AB
this.pageSize = pageSize; ooUVVp
} y.J>}[\&x
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publicint getTotalCount(){ Q}OloA(+
return totalCount; FZ?eX`,
} m7g*zu2#
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publicvoid setTotalCount(int totalCount){ kx?Yin8K
if(totalCount > 0){ (lVMy\
this.totalCount = totalCount; 1 =C12
int count = totalCount / @R50M (@W
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pageSize; MiIxj%,(
if(totalCount % pageSize > 0) vN\[2r%S
count++; gqy>;A:kO
indexes = newint[count]; B K+P
for(int i = 0; i < count; i++){ xh$yXP0/
indexes = pageSize * t_w\k_
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i; ]!"w?-h Si
} <tFq^qB
}else{ h7q{i|5
this.totalCount = 0; 5l1R")0`t_
} #jg-q|nd
} U\H[.qY-
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publicint[] getIndexes(){ W1X3ArP]m8
return indexes; SfC* ZM}<
} sV,Yz3E<u$
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publicvoid setIndexes(int[] indexes){ #<b\B qYG
this.indexes = indexes; vw;aL#PP
} 7)jN:+4N
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publicint getStartIndex(){ [BD`h
return startIndex; g^+p7G
} bKM*4M=k
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publicvoid setStartIndex(int startIndex){ ;!S5P(
if(totalCount <= 0) JS^DyBXc
this.startIndex = 0; /Tm+&Jd
elseif(startIndex >= totalCount) s0;a j<J
this.startIndex = indexes 4h|*r !
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[indexes.length - 1]; xH:L6K/c
elseif(startIndex < 0) z+Fu{<#(
this.startIndex = 0; ]b%U9hmL^f
else{ .(q'7Q Z/
this.startIndex = indexes A(E}2iP9=
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[startIndex / pageSize]; L5I!YP#v
} :Q("
} E,.PT^au
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publicint getNextIndex(){ B;(U?gC
int nextIndex = getStartIndex() + #%nV\ Bl
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pageSize; &Ril[siw
if(nextIndex >= totalCount) {guOAT-w
return getStartIndex(); fub04x)
else ?j/FYi
return nextIndex; W.[!Q`
} 4RVqfD
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publicint getPreviousIndex(){ ) dk|S\
int previousIndex = getStartIndex() - 4Z%1eOR9V
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pageSize; MF< ZB_@
if(previousIndex < 0) oFP8s[B
return0; (+(@P*c1
else vq(#Ih2
return previousIndex; D#1R$4M=
} ]$L5}pE3
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} <!>\
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抽象业务类 ;:
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java代码: wl]3g
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/** Wj,s/Yr:
* Created on 2005-7-12 -)(=~|,Pq/
*/ J$yq#LBbR@
package com.javaeye.common.business; ^wBlQmW7J
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import java.io.Serializable; j36YIz$a
import java.util.List; _N|%i J5
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import org.hibernate.Criteria; /jJD
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import org.hibernate.HibernateException; `$JvWN,kB
import org.hibernate.Session; '(B -{}l
import org.hibernate.criterion.DetachedCriteria; 7mYcO3{5{
import org.hibernate.criterion.Projections; Vxap+<m
import }_KzF~
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org.springframework.orm.hibernate3.HibernateCallback; w*XM*yJHU
import %pq.fZI
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org.springframework.orm.hibernate3.support.HibernateDaoS nm#23@uZ4K
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upport; BkB_?^Nv8
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import com.javaeye.common.util.PaginationSupport; hOk9 y=
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public abstract class AbstractManager extends Vv+nq_
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HibernateDaoSupport { UZs '[pm)
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privateboolean cacheQueries = false; 8[J%TWq%9
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privateString queryCacheRegion; El9T>!Z
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publicvoid setCacheQueries(boolean /Q@4HV
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cacheQueries){ Hb*Z_s
this.cacheQueries = cacheQueries; </_QldL_
} v[uVAbfQ
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publicvoid setQueryCacheRegion(String j7&#R+f
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queryCacheRegion){ =I'iD0eR
this.queryCacheRegion = Y<W9LF
}bw^p.ci
queryCacheRegion; `?=3[
} d4IQ;u
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publicvoid save(finalObject entity){ p9i7<X2&
getHibernateTemplate().save(entity); !U@ETo
} 83vZRQw
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publicvoid persist(finalObject entity){ ' u<I S/w
getHibernateTemplate().save(entity); ^n~Kr1}nj
} A*0X~6W
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publicvoid update(finalObject entity){ r+%3Y:dZE
getHibernateTemplate().update(entity); _hV34:1F
} hb8oq3*x
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publicvoid delete(finalObject entity){ RvA "ug.*
getHibernateTemplate().delete(entity); bl!pKOY
} 4IZAJqw(*
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publicObject load(finalClass entity, $G0e1)D
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finalSerializable id){
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return getHibernateTemplate().load kPy7e~
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(entity, id); IW nG@!
} _^{RtP#=
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publicObject get(finalClass entity, 4Kj8i
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finalSerializable id){ [%LGiCU]
return getHibernateTemplate().get aC9iNm8w
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(entity, id); &/' O?HWl
} dh{py
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publicList findAll(finalClass entity){ FDiDHOR
return getHibernateTemplate().find("from W1o6Sh8v(
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" + entity.getName()); C4X3;l Z%S
} L1`^M
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publicList findByNamedQuery(finalString 0 "@J*e#
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namedQuery){ xZq, kP^
return getHibernateTemplate _,F\%}
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().findByNamedQuery(namedQuery); `mZ1!I-T
} i%f
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publicList findByNamedQuery(finalString query, k=Wt57jt
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finalObject parameter){ /HqD4GDoug
return getHibernateTemplate =RWY0| f
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().findByNamedQuery(query, parameter); fe6Op
} _Co
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publicList findByNamedQuery(finalString query, l) KN5V
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finalObject[] parameters){ Pa; *%7
return getHibernateTemplate Sxy3cv53
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().findByNamedQuery(query, parameters); 2mx }bj8
} 4Im}!q5;:<
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publicList find(finalString query){ )5<dmK@
return getHibernateTemplate().find JO87rG
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(query); @6U&7!
} f|!@H><
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publicList find(finalString query, finalObject m|Z[8Tup
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parameter){ el^<M,7!
return getHibernateTemplate().find !VfVpi+-
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(query, parameter); jd+HIR
} @:9mTP7
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public PaginationSupport findPageByCriteria PO2]x:
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(final DetachedCriteria detachedCriteria){ M?$tHA~OX
return findPageByCriteria hn/SS
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); URTJA<r8D
} *41WZ E
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public PaginationSupport findPageByCriteria y+VRD
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(final DetachedCriteria detachedCriteria, finalint C4C!-12
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startIndex){ E~Y%x/oX
return findPageByCriteria lU3Xd_v
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(detachedCriteria, PaginationSupport.PAGESIZE, rmnnV[@o
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startIndex); `udZ =S"/L
} `VOLw*Ci
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public PaginationSupport findPageByCriteria jM(!!AjpC
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(final DetachedCriteria detachedCriteria, finalint tgm(tDL
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pageSize, [6Nzz]yy
finalint startIndex){ !]WC~#|{B
return(PaginationSupport) d e~3:
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getHibernateTemplate().execute(new HibernateCallback(){ V -9z{
publicObject doInHibernate
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%O&C\{J
(Session session)throws HibernateException { cE]#23
Criteria criteria = Z{.L_]$I
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detachedCriteria.getExecutableCriteria(session); 15~+Ga4
int totalCount = zzBq b\Ky
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((Integer) criteria.setProjection(Projections.rowCount 'r?OzFtxh
su]ywVoRT
()).uniqueResult()).intValue(); `<l|XPv
criteria.setProjection
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(null); } "ts
List items = 6Bm2_B
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criteria.setFirstResult(startIndex).setMaxResults k-vxKrjZ/
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(pageSize).list(); @$'1
PaginationSupport ps = D+
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new PaginationSupport(items, totalCount, pageSize, P%Ux-0&
5{|\h}
startIndex); KGX?\#-
return ps; )Z 3fytY
} NeyGIEP
}, true); H{T)?J~
} VI`x
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public List findAllByCriteria(final [}_ar
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DetachedCriteria detachedCriteria){ fJC,ubP[5
return(List) getHibernateTemplate @]h#T4z'
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().execute(new HibernateCallback(){ :+,qvu!M7
publicObject doInHibernate '17u
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(Session session)throws HibernateException { Ic/<jFZXM
Criteria criteria = U-s6h;^O
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detachedCriteria.getExecutableCriteria(session); !J'xk
return criteria.list(); HF\L`dJX?
} uS|Zkuk[!
}, true); U%45qCU
} d*,|?Ar*b
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public int getCountByCriteria(final %3VwCuE
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DetachedCriteria detachedCriteria){ *qBMt[a
Integer count = (Integer) 1^Zx-p3J
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getHibernateTemplate().execute(new HibernateCallback(){ %9NGVC
publicObject doInHibernate l>&)_:\
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(Session session)throws HibernateException { $@&bK2@.(
Criteria criteria = y9)l,@D
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detachedCriteria.getExecutableCriteria(session); Hab9~v ]
return y~S[0]y>
t8)Fkx#8}
criteria.setProjection(Projections.rowCount l2`8]Qr
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()).uniqueResult(); H[Pb Wy:
} Z21XlbK
}, true); BS|-E6E<
return count.intValue(); P7y[9|^
} *BO4"3Z
} In;z\"NN4
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用户在web层构造查询条件detachedCriteria,和可选的 bL[PNUG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 g<dCUIbcQ
1)PR]s:-m@
PaginationSupport的实例ps。 TwhK>HN
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ps.getItems()得到已分页好的结果集 /pge 7P
ps.getIndexes()得到分页索引的数组 RU>vnDaC
ps.getTotalCount()得到总结果数 <|`@K|N
ps.getStartIndex()当前分页索引 \rN_CBM
ps.getNextIndex()下一页索引 8|tm`r`*Az
ps.getPreviousIndex()上一页索引 %5KR}NXX6
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V$_0VN'+Z
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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 ,6bMfz
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一下代码重构了。 =iQm_g
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我把原本我的做法也提供出来供大家讨论吧: Ww@;9US 3
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首先,为了实现分页查询,我封装了一个Page类: 4a |Fx
java代码: T> 'Vaxo
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/*Created on 2005-4-14*/ ^k(eRs;K
package org.flyware.util.page; csM|VNE>
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/** C941@I
* @author Joa T6r~OV5
* &NQR*Tn
*/ )It4al^\
publicclass Page { 5mNXWg7#]
UhTr<(@
/** imply if the page has previous page */ $I36>
privateboolean hasPrePage; $?-o
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/** imply if the page has next page */ |Z^g\l.j{
privateboolean hasNextPage; z{0;%E
tQaCNS$=
/** the number of every page */ ;T+U&U0d|
privateint everyPage; <xjv7`G7
jFTV\|C
/** the total page number */ vaOL6=[#:g
privateint totalPage; .6F3;bg R7
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/** the number of current page */ C+?s~JL
privateint currentPage; faOWhIG
&:#8ol(n5b
/** the begin index of the records by the current PjW+V`
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query */ 08?MS_
privateint beginIndex; 7U`S9DDwq
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1 "7#|=1/
/** The default constructor */ ]U1,NhZu
public Page(){ EJ ~kZ3
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} 9Pp|d"6]y
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/** construct the page by everyPage K!c@aD:#
* @param everyPage 3e6Y
* */ [ky6E*dV`
public Page(int everyPage){ i!$^NIcJ
this.everyPage = everyPage; &:I
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} dX@A%6#?
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/** The whole constructor */ EN)A"
public Page(boolean hasPrePage, boolean hasNextPage, n`z+ w*
}`N2ZxC0AQ
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int everyPage, int totalPage, 8Cs$NUU
int currentPage, int beginIndex){ MR_bq_)
this.hasPrePage = hasPrePage; )Ct*G=
N
this.hasNextPage = hasNextPage; (5q%0|RzRs
this.everyPage = everyPage; 51M^yG&M
this.totalPage = totalPage; AMD?LjY~
this.currentPage = currentPage; 1!(%<R
this.beginIndex = beginIndex; !UMo4}Y
} f3TlJ!!U
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/** #xP!!.DF(
* @return DqzA U7
* Returns the beginIndex. OOBcJC
*/ TA0D{
publicint getBeginIndex(){ ft/^4QcyAM
return beginIndex; j:e^7|.
} W>0"CUp
B80odU&
/** PNJe&q0*
* @param beginIndex fNqmTRu
* The beginIndex to set. ^V: "zzn&
*/ >nhE%:X>
publicvoid setBeginIndex(int beginIndex){ IypWVr
this.beginIndex = beginIndex; R#/?AD&
}
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/** 7rdw`
* @return "X5_-l
* Returns the currentPage. |0L=8~M(j
*/ b4v(k(<
publicint getCurrentPage(){ <rB3[IJo
return currentPage; Zlk,])9 Q
} o9ctJf=qn
v]:+`dV
/** *qPdZ
* @param currentPage \L ]
* The currentPage to set. _r\$NgJIM
*/ I7fb}j`/
publicvoid setCurrentPage(int currentPage){ J%\- 1
this.currentPage = currentPage; jC%35bi
} zLsb`)!
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/** ;8ET!&k*>E
* @return )N"Ew0U
* Returns the everyPage. 46bl>yk9<
*/ pb^,Qvnp
publicint getEveryPage(){ oZvA~]x9\
return everyPage; %9C`
} y?pD(u
b!0DH[XKV
/** +T0op4
* @param everyPage <4bz/^
* The everyPage to set. 7qe7Fl3
*/ /!GKh5|
publicvoid setEveryPage(int everyPage){ {O^TurbTFA
this.everyPage = everyPage; %K[daXw6E8
} _1^8xFe2
5@P%iBA4(3
/** `)R?nVb
* @return )K~w'TUr
* Returns the hasNextPage. hv*>%p
*/ Hjs}
publicboolean getHasNextPage(){ bfgz1
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return hasNextPage; Q%ruQ#
} AL$W +')
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/** *>jjMy n
* @param hasNextPage *E:x E/M!2
* The hasNextPage to set. F4Zn5&.)
*/ k$h [8l(<
publicvoid setHasNextPage(boolean hasNextPage){ ,c>N}*6h=W
this.hasNextPage = hasNextPage; aG%kmS&fv
} >':5?\C+-
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/** x97L6!
* @return <FY&h#
* Returns the hasPrePage. m0|K#^
*/ mN;+TN'?{
publicboolean getHasPrePage(){ St@l]u9
return hasPrePage; 7+}JgUh
} #~^btL'dHF
j{"z4Y4
/** "O*x' XhN
* @param hasPrePage o0ZIsrr
* The hasPrePage to set. .NJ|p=fy
*/ V8hO8
publicvoid setHasPrePage(boolean hasPrePage){ 740B\pc0
this.hasPrePage = hasPrePage; <} ,1Ncl
} -v+&pG?m
k[\a)WcY8
/** ;+ azeW^
* @return Returns the totalPage. nnwJYEi
* IG< H"tQ
*/ i|]7(z#OyI
publicint getTotalPage(){ hQRL,?
return totalPage; 2*[QZ9U[@
} E{4 e<%Y,
~.^AL}zm_
/** y6-XHeU
* @param totalPage O0T/#<Cn!
* The totalPage to set. hmpr%(c `
*/ VfSj E.|
publicvoid setTotalPage(int totalPage){ 4zjs!AK%
this.totalPage = totalPage; jVO{$j
} eQUe
>*
qnChM;)
} |4;UyHh
c6&Q^p|CF
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7I9aG.;
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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 AiP!hw/V$
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个PageUtil,负责对Page对象进行构造: x|i_P|Z
java代码: SmhGZ
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/*Created on 2005-4-14*/ E5</h"1
package org.flyware.util.page; a0=WfeT
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import org.apache.commons.logging.Log; GbI-SbE
import org.apache.commons.logging.LogFactory; d\]Yk]r
6gH{R$7L=
/** %<0eA`F4
* @author Joa W$0^(FH[
* q{0R=jb
*/ V5i*O3a~
publicclass PageUtil { [ sF(#Y:I
aNxAZMg
privatestaticfinal Log logger = LogFactory.getLog }}|)Yq
pav'1d%
(PageUtil.class); >UDd @
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/** q_kdCO{:df
* Use the origin page to create a new page #bX9Tu0
* @param page m3bCZ9iE
* @param totalRecords 6$\jAd|
* @return 4_A0rveP
*/ ntFT>g{B
publicstatic Page createPage(Page page, int @$9'@")
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totalRecords){ ziPR>iz-
return createPage(page.getEveryPage(), Gg Jf7ie4
':{>a28=
page.getCurrentPage(), totalRecords); 7%f&M>/
} El\%E"Tk%
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/** I/Jb!R ~
* the basic page utils not including exception k:jSbbQ
@+3kb.P%7
handler *g?Po+ef%
* @param everyPage }>)[<;M>%
* @param currentPage "&/-N[is
* @param totalRecords !?c|XdjZ
* @return page >B]'fUt5a
*/ T,aW8|
publicstatic Page createPage(int everyPage, int _SW3_8SuM.
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currentPage, int totalRecords){ MxT-1&XL
everyPage = getEveryPage(everyPage); sMu]
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currentPage = getCurrentPage(currentPage); ~e6Brq
int beginIndex = getBeginIndex(everyPage, h1'\:N`
i3rH'B-I.
currentPage); hjZKUMG(k
int totalPage = getTotalPage(everyPage, 89r DyRJ;
+$g}4
totalRecords); x)( |[
boolean hasNextPage = hasNextPage(currentPage, BD(Z5+EU1
uEX!xx?Q#
totalPage); .l.a(_R
boolean hasPrePage = hasPrePage(currentPage); ]]zPq<b2
293M\5:
returnnew Page(hasPrePage, hasNextPage, #B4%|v;`E?
everyPage, totalPage, c%MW\qx
currentPage, :Nz9xD$S5
dq]0X?[6
beginIndex); e)(wss+d7P
} @3zg=?3
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privatestaticint getEveryPage(int everyPage){ zG(\+4GE!
return everyPage == 0 ? 10 : everyPage; 9jw\s P@
} UEguF&
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privatestaticint getCurrentPage(int currentPage){ oz,e/v8~
return currentPage == 0 ? 1 : currentPage; #w' kV#
} b:TLV`>/&
HhvdqvIEG
privatestaticint getBeginIndex(int everyPage, int c-(UhN3WG
sVOyT*GY
currentPage){ |aVn&qK
return(currentPage - 1) * everyPage; / G7vwC
} B!?%O
c9&xe"v
privatestaticint getTotalPage(int everyPage, int oC0qG[yp9S
njputEGX
totalRecords){ a ?)NC
int totalPage = 0; AJF#Aw `o
2Eu`u!jhx
if(totalRecords % everyPage == 0) uC(V
totalPage = totalRecords / everyPage; %-1O.Q|f
else Y2~nBb
totalPage = totalRecords / everyPage + 1 ; ppVHLrUh
;EP:o%r
return totalPage; w|K'M?N14
} 4bYK}oS
8ap%?
privatestaticboolean hasPrePage(int currentPage){ 7_inJ$
return currentPage == 1 ? false : true; v@
lM3_rbO
} Na]:_K5Dp
^LoUi1j
privatestaticboolean hasNextPage(int currentPage, 6\q]rfQ
rE.;g^4p
int totalPage){ RwpdRBb
return currentPage == totalPage || totalPage == D$I5z.a
,)Znb=
0 ? false : true; j~[z2tV
} qKr8)}h
Ws|j#X<
:&V h?
} ?kbiMs1;u
c7x~{V8
4R1<nZ"e~
vunHNHltW0
LnH ?dy
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。 CYY=R'1:G{
$QLcH;+7t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8
Hg+H=?
2fnkw/
做法如下: 0=2@
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \Je0CD=e`
r\'A
i6
的信息,和一个结果集List: ) l:[^$=,
java代码: q_A!'sm@)
Vt:~q{9*k
iTgt}]L
/*Created on 2005-6-13*/ OR~8sU
package com.adt.bo; <lx+/o
&8Cu#^3
import java.util.List; mwHB(7YS,
$P^q!H4D
import org.flyware.util.page.Page; S2sQOM@
N4F.Y"R$(
/** 6xTuNE1
* @author Joa MyJ%`@+1
*/ 5\:^y'g[
publicclass Result { -*X a3/kQ
*x@Onj
private Page page; .WA-&b_
CQF:Rnb
private List content; 5Ha9lM2gh
5q3JI
/** gmw|H?]
* The default constructor cQCSe,$ W
*/ SJb&m-
public Result(){ . qO@Q =
super(); 2_HNhW
} EE&K0<?T|:
#Z?A2r!1
/** bzBEX mC
* The constructor using fields H1|?t+oP
* ype$ c
* @param page _.tVSVp
* @param content =_JjmTy;a
*/ >E;uU[v)I
public Result(Page page, List content){ 5Dm.K?l;
this.page = page; #A1%gIw<v2
this.content = content; 9-&Ttbb4)0
} sJL&:!}V>
^oBtfN>4
/** :~&~y-14
* @return Returns the content. FH?U(-
*/ \)#kquH/l
publicList getContent(){ 1H?
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return content; HVR /7&g
} ry`Ho8N
x-WmMfcz&
/** ak$f"py
x
* @return Returns the page. X`kk]8=
*/ lA|
5E?
public Page getPage(){ oK6tTK
return page; ?GKb7Oj
} >)fi^
q/4J.jL
/** 9UdM`v)(
* @param content rK' L6o
* The content to set. W9 GxXPA
*/ !Q2d(H>
public void setContent(List content){ XRM_x:+]
this.content = content; $v4.sl:x
} JFcLv=U
#^u$
/** eBZXI)pPh
* @param page 6a(yp3
* The page to set. dI.WK@W'o
*/ w1Nm&}V
publicvoid setPage(Page page){ g0xuxK;9c
this.page = page; "h{q#~s
} kj#?whK6~
} v|XTr,#
g/ T
| k&Ck
[L3=x;U
CM/H9Kz.
2. 编写业务逻辑接口,并实现它(UserManager, $O&b``
9&-dTayIz
UserManagerImpl) Sq>dt[7
java代码: DrKP%BnS
|HiE@
y`Wty@
/*Created on 2005-7-15*/ >:74%D0UF
package com.adt.service; yZ0-wI
g!g#]9j
import net.sf.hibernate.HibernateException; jD$,.AVvz
"@e3EX7h
import org.flyware.util.page.Page; =_.l8IYX$%
dN$0OS`s[
import com.adt.bo.Result; e>} s;H,
.[]r}[ lU
/** X&tF;<m^
* @author Joa Ep9nsX*
*/ ;km`P|<U
publicinterface UserManager { zJq~!#pZ
j8v8uZ;x
public Result listUser(Page page)throws 7x"R3
tqz3zIQ
HibernateException; k :(SCHf
\\iQEy<i
} "3X2VFwoJ
VACQ+
&|s0P
R6` WN
iOd&BB6
java代码: <wk!hTmW
qmkAg }2
HZ aV7dOZ8
/*Created on 2005-7-15*/ 1T"`vtR
package com.adt.service.impl; F|'>NL-=
&p'Y^zL-
import java.util.List; hr#M-K
{BP{C=p
import net.sf.hibernate.HibernateException; "M<8UE \n
d`QN^)F0#
import org.flyware.util.page.Page; iFd+2S%
import org.flyware.util.page.PageUtil; TJ10s%,V
8H%;WU9-
import com.adt.bo.Result; iN bIp"W
import com.adt.dao.UserDAO; }5ret
import com.adt.exception.ObjectNotFoundException; +5w))9@
import com.adt.service.UserManager; 2~Kgv|09
R[zpD%CI
/** $.Qkb@}
* @author Joa ]&o$b ]
*/ ;;!yC
publicclass UserManagerImpl implements UserManager { NxkGOAOE
..IfP@
private UserDAO userDAO; VpE*(i$
~8PZ5;g
/** u}#(.)a:
* @param userDAO The userDAO to set. 1vS#K=sb
*/ Ow+GS{-q
publicvoid setUserDAO(UserDAO userDAO){ LD+{o 4i
this.userDAO = userDAO; 216 RiSr*
} TJ2=m9Z
{0[tNth'h
/* (non-Javadoc) >BV^H.SO|1
* @see com.adt.service.UserManager#listUser x)
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]3D0R;
(org.flyware.util.page.Page) b_$4V3TA
*/ AiwOc+R
public Result listUser(Page page)throws tP:lP#9
BOX{]EOj
HibernateException, ObjectNotFoundException { T(#J_Y
int totalRecords = userDAO.getUserCount(); R}-(cc%5
if(totalRecords == 0) 4zXFuTr($
throw new ObjectNotFoundException F8nYV
>"??!|XG^
("userNotExist"); e6`Jbu+J<f
page = PageUtil.createPage(page, totalRecords); 0CWvYC%e
List users = userDAO.getUserByPage(page); '*Z1tDFS
returnnew Result(page, users); `XJG(Oas\
} R
MR;1
2*p
} YDIG,%uv
RF`.xQ26=
=-0/k;^
1D7nkAy
WltQ63u
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xzdf^Ce
GF"hx`zyJ
询,接下来编写UserDAO的代码: {dhXIs
3. UserDAO 和 UserDAOImpl: _:ReN_0
java代码: -Fi`Z$
Wvq27YK'
B?OFe'*
/*Created on 2005-7-15*/ o8 IL$:
package com.adt.dao; WO7z
8^kGS-+^
import java.util.List; /}((l%U E.
u0}vWkn\4
import org.flyware.util.page.Page; L 8c0lx}Nn
B |5]Jm]
import net.sf.hibernate.HibernateException; kGH }[w
s%vis{2
/** R6 y#S&]x
* @author Joa ^+*N%yr
*/ 5 )A1\
publicinterface UserDAO extends BaseDAO { *1ilkmL%
|5X^u+_
publicList getUserByName(String name)throws jSJqE_ 1
y|jl[pyg)
HibernateException; [ZNtCnv
zKyyU}LHH
publicint getUserCount()throws HibernateException; b10cuy|a/X
tl[Uw[
publicList getUserByPage(Page page)throws 'S20\hwt-
<kfnpB=
HibernateException; ({ +!`}GY
/?wtF4
} To\QjP-
OstQqV%@
GiJ *Wp
i"1Mfz~e
O+nEXS\rQ
java代码: jkQ*D(;p
k)i3
W6^5YH%
/*Created on 2005-7-15*/ jqz ux[6{
package com.adt.dao.impl; $6#CqWhI
L,HhbTRca
import java.util.List; `A,-@`p
gl~ecc
import org.flyware.util.page.Page; q?H|o(
!-g{[19\
import net.sf.hibernate.HibernateException; ]dF
,:8
import net.sf.hibernate.Query; 9G9t" {
?Lx24*5%
import com.adt.dao.UserDAO; ww)<E`eGi
-r!. 9q
/** dydc}n
* @author Joa "0$a)4]
*/ FK^p")i
public class UserDAOImpl extends BaseDAOHibernateImpl
T5|qRlW
biL s+\C
implements UserDAO { Z
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Vk`h2BV
/* (non-Javadoc) mJ<=n?{Z
* @see com.adt.dao.UserDAO#getUserByName Qu"8(Jk/
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q
(java.lang.String) _aq8@E~
*/ t;){D:]k
publicList getUserByName(String name)throws &]Q@7Nl7:l
o m!!Sl 3
HibernateException { /hpY f]t
String querySentence = "FROM user in class c|f<u{'
l\f*d6o
com.adt.po.User WHERE user.name=:name"; J;S
(>c
Query query = getSession().createQuery y3vdUauOn
dR
K?~1
(querySentence); bes<qy
query.setParameter("name", name); 4M^=nae
return query.list(); oxr#7Ei0d
} yyR0]NzYUD
I.I`6(Cb
/* (non-Javadoc) )i6mzzj5
* @see com.adt.dao.UserDAO#getUserCount() &`h{iK7
*/ R1PkTZP&
publicint getUserCount()throws HibernateException { =WyDp97@+
int count = 0; H!c@klD
String querySentence = "SELECT count(*) FROM u+dLaVlLJ
} FE>|1
user in class com.adt.po.User"; wDw[RW3
Query query = getSession().createQuery N[?N5~jG
OwuE~K7b{
(querySentence); aasoW\UG
count = ((Integer)query.iterate().next 5b5x!do
c7 ?_46J
()).intValue(); -Mip,EO
return count; P=qa::A
} #OZ>V3k
CZ8KEBl
/* (non-Javadoc) \TIT:1
* @see com.adt.dao.UserDAO#getUserByPage ]{!U@b
eFipIn)b
(org.flyware.util.page.Page) '|ad_M
*/ y~(h>gi,x
publicList getUserByPage(Page page)throws .n TwPrG
\-L&5x"x
HibernateException { U1Q:= yD
String querySentence = "FROM user in class rUTcpGH
}pDqe;a{
com.adt.po.User"; XWDL5K
Query query = getSession().createQuery ~W*FCG#E
=pr`'
(querySentence); "7U4'Y:E
query.setFirstResult(page.getBeginIndex()) 1f%1*L0>@
.setMaxResults(page.getEveryPage()); T
_r:4JS
return query.list(); oVnvO iAc
} 60P<4
"33Fv9C#bK
} rUwZMli
bw(a6qKK
#:jHp44J
V4hiGO[
Fiv3 {.
至此,一个完整的分页程序完成。前台的只需要调用 G, 44va
p5Z"|\
userManager.listUser(page)即可得到一个Page对象和结果集对象 <5d~P/,
FO+Zue.RS
的综合体,而传入的参数page对象则可以由前台传入,如果用 Moy <@+
svsq g{9z
webwork,甚至可以直接在配置文件中指定。 -#7'r<I9@
,NOsFO-`<
下面给出一个webwork调用示例: ~Io7]
java代码: j_/>A=OD
*lYVY)L
-^K"ZP1
/*Created on 2005-6-17*/ ^"2i
package com.adt.action.user; ~Uu4=
e%@'5k\SK
import java.util.List; 0\H\lKcK
;m0~L=w
import org.apache.commons.logging.Log; :Hn6b$Vy8
import org.apache.commons.logging.LogFactory; :uP,f<=)K
import org.flyware.util.page.Page; kh!FR u h
vhe>)h*B
import com.adt.bo.Result; VdPtPq1
import com.adt.service.UserService; ?OId\'q
import com.opensymphony.xwork.Action; O $LfuL
rr+|Zt
Y
/** l#m#c6;=
* @author Joa vV6<^W:9F
*/ Sw:7pByjI
publicclass ListUser implementsAction{ oNr-Q& C,
H[{F'c[e
privatestaticfinal Log logger = LogFactory.getLog E8!e:l
=Q
d.3E[AJa(
(ListUser.class); d<% z
1Dj2
B%"
d~5Y
private UserService userService; $}RJ,%~'x
!4]TXH0f
private Page page; O80<Z#%j`
@>u]4Jn
privateList users; \@WDV
l2`s! ,<>O
/* r/4``shg
* (non-Javadoc) [V^WGW2oY
* |"?M 1*g
* @see com.opensymphony.xwork.Action#execute() FI[A[*fi
*/ 3Q"<<pi!~
publicString execute()throwsException{ lun#^ J
Result result = userService.listUser(page); 1uG"f<TsR
page = result.getPage(); "&%I)e^
users = result.getContent(); ;>#wU'
return SUCCESS; <
nXL
} ht7l- AK
ATJWO1CtB
/** 7[w,:9& }
* @return Returns the page. TBs|r#
*/ 6{x(.=
public Page getPage(){ ,kF1T,
return page; C.~,qmOP
} Vdtry@Q
c$ao:nP)D
/** *Y,x|F
* @return Returns the users. YbR!+ 0\g
*/ M2d$4-<
publicList getUsers(){ yQU_>_!n
return users; FO=4:
} mN~ci 0
PjZvQ\Z
/** ?<V?wsp
* @param page b$4"i XSQ
* The page to set. XnDUa3
*/ 11TL~xFh
publicvoid setPage(Page page){ ~kQA7;`j$
this.page = page; N2B|SO''
} 'U1R\86M
*$yR*}A
/** _/F7?^j
* @param users Y?S!8-z
* The users to set. %Qc La//
*/ Hcl(3>Jn2
publicvoid setUsers(List users){ >v:y?A,
this.users = users;
5Ec6),+&
} {F3xJ[
prYs
$j
/** &{ay=Mj
* @param userService 5XO;N s
* The userService to set. Q7*SE%H
*/ JF # #
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publicvoid setUserService(UserService userService){ kv3E4,<9
this.userService = userService; 3_txg>P"
} 4~y(`\0?4
} %oq{L]C(rf
+Fuqchjq
M%Ji0v38
=5Q]m6-SgV
2-7IJ\
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, d^RxQuA
IHe/xQ@
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 j2ve^F:Q
1HXjN~XF
么只需要: *;1,5L
java代码: p=;=w_^y
O]lSWEe
e91aK
<?xml version="1.0"?> pv*,gSS
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Y'yH;Mz
DKne'3pH
1.0//EN" "http://www.opensymphony.com/xwork/xwork- TFH \K{DM
mk1bcK9
1.0.dtd"> DSC$i|
Px$/ _`H
<xwork> 0TCBQ~ "
{aY%gk?y#>
<package name="user" extends="webwork- plUZ"Tr
M\sN@+
interceptors"> eb.O#Y
3x5JFM
<!-- The default interceptor stack name [baiH|5>
t0o`-d(
--> =o
Xsb
<default-interceptor-ref ZNf6;%oGG
{)"iiJ
name="myDefaultWebStack"/> 6qRx0"qB
H18Tn!RDS
<action name="listUser" d
p2 F
#1`-*.u
class="com.adt.action.user.ListUser"> >xF/Pl
<param \Z]UA&v_
eAXc:222
name="page.everyPage">10</param> v\!Be[ ?
<result bvS(@
afv~r>q(-
name="success">/user/user_list.jsp</result> OZx
W?wnd
</action> AmaT0tzJC
]e^c=O`$
</package> }R1<
0~g
s>0't
</xwork> T,]7ICF#
j/>$,
$>GgB`
\Kl+ 5%L
X *&[u7No
]%|GmtqZs,
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 #bMuvaP~
Qj,]N@7
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 7[I}*3Q'
4kG,*3&2
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 S/^"@?z,vE
X}tVmO?
N$h{Yvbn
&0NFb^8+
.z
6fv
我写的一个用于分页的类,用了泛型了,hoho GqWB{$J;"
2W/?q!t
java代码: T?
tG~
])L
A42|
CZ(/=3,3n
package com.intokr.util; & @s!<9$W
I2 j}Am
import java.util.List; 4G$|Rx[{,
l7W 6qNB
/** <1FC%f/
* 用于分页的类<br> E0u~i59Z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> D[^m{ 9_
* 5!l0zLQPo
* @version 0.01 wS4.8iJ
* @author cheng RT)d ]u
*/ <z]cyXv/
public class Paginator<E> { J13>i7]L%
privateint count = 0; // 总记录数 aemc2b*
privateint p = 1; // 页编号 <4_X P.N
privateint num = 20; // 每页的记录数 5#> 8MU?&
privateList<E> results = null; // 结果 #gp,V#T
`|,`QqDQ
/** }*lUah,@
* 结果总数 +w.JpbQ&
*/ >c9a0A
publicint getCount(){ 11<Qxu$rL
return count; #tZ4N7
} |55N?=8
/G5d|P
publicvoid setCount(int count){ AT9q3
this.count = count; T-5nB>)
} h&`e) a>+
hg+X(0
/** :@ %4
* 本结果所在的页码,从1开始 y>72{
* DTaN"{
* @return Returns the pageNo. Ys,{8Y,7
*/ 3jlh}t>$l
publicint getP(){ zY|t0H
return p; `0P$#5?
} GG@md_
s}jHl8
/** F'B8v3
* if(p<=0) p=1 J]&y$?C
* 4F{)i
* @param p LM7$}#$R
*/ `FYv3w2
publicvoid setP(int p){ XVKfl3'%
if(p <= 0) 5]HS^II"
p = 1; RA G3o-
this.p = p; qQ"Fv|]~>
} NR -!VJQ
!1q 9+e
/** E}sO[wNPf
* 每页记录数量 |4T!&[r
*/ E-I-0h2
publicint getNum(){ 0%m)@ukb
return num; xKQ+{"?-^g
} {_S}H1,
zipS
]YD
/** Aj2OkD
* if(num<1) num=1 ~ECD`N<YF
*/ r6&54f
publicvoid setNum(int num){ ,Fi>p0bz
if(num < 1) ~$p2#AqX
num = 1; o(S{VGi,
this.num = num; hO';{Nl/$
} ?Rj ~f{%g
hir4ZO%Zt
/** \T<$9aNb
* 获得总页数 Gm(b/qDDe
*/ Kj<^zo%w
publicint getPageNum(){ ^}:#
return(count - 1) / num + 1; 3'^k$;^
} 6xZ=^;H
" )V130<
/** b|+wc6
* 获得本页的开始编号,为 (p-1)*num+1 ~-PjW#J%
*/ rk7QZVE
publicint getStart(){ R,|d`)T
return(p - 1) * num + 1; G(~;]xNW+
} r8,romE$
nWMmna.5
/** Kt"BE j
* @return Returns the results. k'#(1(xj
*/ ;gs
^%z
publicList<E> getResults(){ E;1Jh(58)b
return results; I_xXDr
} {W]=~*w
]79:yMD~ba
public void setResults(List<E> results){ ox%9Ph
this.results = results; N_pJk2E
} 1qf!DMcdZ
(iRide
public String toString(){ I =1+h
StringBuilder buff = new StringBuilder /w]!wM
R1& [S/
(); 55;g1o}}f
buff.append("{"); aBNZdX]vzO
buff.append("count:").append(count); dw TMq*e
buff.append(",p:").append(p); I('Un@hS
buff.append(",nump:").append(num); v>Mnl
buff.append(",results:").append Rr!Y3)f;
7^Ns&Q
(results); v{9t]s>B
buff.append("}"); X`fn8~5
return buff.toString(); C&6IU8l\
} 7f~Sf
_L@2_#h!
} ,2j.<g&
5vw{b?
Q4*fc^?u