Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 M=+M8M`Iy
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^0Q'./A{&
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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 b,Lw7MY}[
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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 _BwKY#09Zp
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分页支持类: M[z3 f
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java代码: Y Z\@)D;
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package com.javaeye.common.util; %`oHemSy
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import java.util.List; ^$}/|d(
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publicclass PaginationSupport { P57GqT
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publicfinalstaticint PAGESIZE = 30; 9'X@@6b*'
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privateint pageSize = PAGESIZE; @Wz%KdXA
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privateList items; Dt|fDw$]D
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privateint totalCount; _'lmCj8L
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privateint[] indexes = newint[0]; E@mkm
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privateint startIndex = 0; _eh3qs:
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public PaginationSupport(List items, int nUqL\(UuY
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totalCount){ S2bexbp0o
setPageSize(PAGESIZE); R Y9.n
setTotalCount(totalCount); My],6va^
setItems(items); g+3Hwtl
setStartIndex(0); J7Sx!PQ
} [!Ao,rt?Vg
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public PaginationSupport(List items, int UtPwWB_YV
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totalCount, int startIndex){ X]MTaD.t
setPageSize(PAGESIZE); B/rzh? b
setTotalCount(totalCount); St_Sl:m$
setItems(items); $-e=tWkgv
setStartIndex(startIndex); )Z&HuEg{ZR
} ;8uHRcdQ
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public PaginationSupport(List items, int {H'X)n$
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totalCount, int pageSize, int startIndex){ yE<,Z%J[n
setPageSize(pageSize); py=i!vb&Z%
setTotalCount(totalCount); *iYMX[$
setItems(items); 5Vm Eyb
setStartIndex(startIndex); X4Lsvvz%@
} i:{:xKiC a
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publicList getItems(){ vyujC`61d
return items; N7a[B>+`
} d0TgqO{
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publicvoid setItems(List items){ VYHOk3
this.items = items; o;E(Kj
} !#C)99L"F
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publicint getPageSize(){ KoFv0~8Q
return pageSize; ";o~&8?)
} 7WXiG0
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publicvoid setPageSize(int pageSize){ s* @QT8%
this.pageSize = pageSize; aE}=^%D
} UC.8DaIPN
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publicint getTotalCount(){ xiEcEz'lk
return totalCount; z_'dRw
} &:-GI)[o
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publicvoid setTotalCount(int totalCount){ /\nJ
if(totalCount > 0){ 0=2H9v
this.totalCount = totalCount; U-ERhm>uk
int count = totalCount /
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.[#xQ=9`
pageSize; {npOlV
if(totalCount % pageSize > 0) /nwxuy
count++; :{x!g6bK@
indexes = newint[count]; y|$vtD%c
for(int i = 0; i < count; i++){ _xa}B,H
indexes = pageSize * ?56~yQF/2
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i; (\T8!s{AO
} \dC.%#
}else{ Cm9 9?K
this.totalCount = 0; 7k.d|<mRv
} MiRibHXI,
} ,xm;JXJ
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publicint[] getIndexes(){ Iv Y,9D
return indexes; 5`(((_Um+
} M-{b
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publicvoid setIndexes(int[] indexes){ oH!$eAU?
this.indexes = indexes; [lmHXf@1C
} MA~|y_V
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publicint getStartIndex(){
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return startIndex; zv8aV2?D
} F<6KaZ|
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publicvoid setStartIndex(int startIndex){ Fr1;)WV
if(totalCount <= 0) p~,a=
this.startIndex = 0; 67Af} >Q
elseif(startIndex >= totalCount) } S'I
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this.startIndex = indexes @9n
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[indexes.length - 1]; Z"teZ0H
elseif(startIndex < 0) Y&ct+w]%
this.startIndex = 0; 0"wbcAh)
else{
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this.startIndex = indexes Xq=!"E
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[startIndex / pageSize]; jKY Aid{-
} $Uv<LVd(
} eONeWY9
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publicint getNextIndex(){ T! &[
int nextIndex = getStartIndex() +
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pageSize; Zztt)/6*
if(nextIndex >= totalCount) ];d5X
return getStartIndex(); =]5DYRhX]
else $S($97IU=
return nextIndex; Nqo#sBS
} 3iwoMrp
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publicint getPreviousIndex(){ nN_94
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int previousIndex = getStartIndex() - (Fbm9(q$d
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pageSize; E :'
if(previousIndex < 0) 3isXgp8
return0; 7Ap~7)z[
else $v?! 6:
return previousIndex; rw=UK`
} *_"c!eW
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} %%-U.
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抽象业务类 61s2bt#
java代码: #(26t _a
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/** N18diP[C
* Created on 2005-7-12 f!uA$uLc
*/ +s*l#'Q
package com.javaeye.common.business; U4^p({\|-
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import java.io.Serializable; gn[$;*932z
import java.util.List; 0Z1H6qn
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import org.hibernate.Criteria; !e#I4,f n
import org.hibernate.HibernateException; QU,TAO
import org.hibernate.Session; LBbo.KxAe3
import org.hibernate.criterion.DetachedCriteria; cV=_GE
import org.hibernate.criterion.Projections; yTq(x4]
import Fy(nu-W
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org.springframework.orm.hibernate3.HibernateCallback; .1[2 CjQ
import /F8\%l+
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org.springframework.orm.hibernate3.support.HibernateDaoS ^b `>/>
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upport; u{{xnyl?
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import com.javaeye.common.util.PaginationSupport; "ZJ1`R=Mj
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public abstract class AbstractManager extends 4f*Ua`E_
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HibernateDaoSupport { 3Ld ;zW
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privateboolean cacheQueries = false; a m k42
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privateString queryCacheRegion; c[d'1=Qiy
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publicvoid setCacheQueries(boolean +O!M>
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cacheQueries){ W|-N>,G
this.cacheQueries = cacheQueries; vA7jZw
} <{z3p:\
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publicvoid setQueryCacheRegion(String v YmtpKNj%
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queryCacheRegion){ +q_lYGTiO
this.queryCacheRegion = PHiX:0zT
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queryCacheRegion; 6<Pg>Bg
} {@K2WB
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publicvoid save(finalObject entity){ ";Ig%]
getHibernateTemplate().save(entity); KutgW#+40
} ^qN1~v=hS
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publicvoid persist(finalObject entity){ n.qxxzEN
getHibernateTemplate().save(entity); 7%"\DLA
} ~:b:_ 5"
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publicvoid update(finalObject entity){ Gv+Tg/
getHibernateTemplate().update(entity); "KI,3g _V
} G$kwc
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publicvoid delete(finalObject entity){ kcz#8K]~
getHibernateTemplate().delete(entity); 5iI3u 7Mn1
} |KrG3-i3X
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publicObject load(finalClass entity, 6 r-n6#=
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finalSerializable id){ 8W<)c
return getHibernateTemplate().load 3;l>x/amk
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(entity, id); *=If1qZs
} Q|H cg|
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publicObject get(finalClass entity, a*8.^SdzR
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finalSerializable id){ K#sb"x`
return getHibernateTemplate().get N[bf.5T
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(entity, id); Oi[9b
} WAmoKZw2
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publicList findAll(finalClass entity){ <W%Z_d&Xv
return getHibernateTemplate().find("from j.N\U#3KK
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" + entity.getName()); Qp.!U~
} Aag)c~D
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publicList findByNamedQuery(finalString R}6la.mQ
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namedQuery){ 1@z@
return getHibernateTemplate 6')SJ*|yS
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().findByNamedQuery(namedQuery); KdMA58)
} !=:MG#p
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publicList findByNamedQuery(finalString query, f=O>\
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finalObject parameter){ PZg]zz=V4
return getHibernateTemplate -&D6w9w
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().findByNamedQuery(query, parameter); 1nTaKK
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} m:Cx~
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publicList findByNamedQuery(finalString query, ]JPPL4wAT
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finalObject[] parameters){ mf_'|
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return getHibernateTemplate i{[H3p8
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().findByNamedQuery(query, parameters); |Pl{Oo+
} !,!tNs1 K
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publicList find(finalString query){ '<D}5u72
return getHibernateTemplate().find ,vw`YKg
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(query); JP@m%Yj
} &:f'{>3z
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publicList find(finalString query, finalObject @5V Z
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parameter){ .+o>
return getHibernateTemplate().find sZBO_](S
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(query, parameter); "hY^[@7 W
} J,KTc'[
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public PaginationSupport findPageByCriteria A?KKZ{Pl
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(final DetachedCriteria detachedCriteria){ ibUPd."W
return findPageByCriteria Nh/ArugP5P
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); BW=6gZ_
} r74w[6(
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public PaginationSupport findPageByCriteria `9{C/qB
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(final DetachedCriteria detachedCriteria, finalint A_U0HVx_
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startIndex){ }mZ*f y0t
return findPageByCriteria e;r-}U
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(detachedCriteria, PaginationSupport.PAGESIZE, #|E. y^IC
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startIndex); cty#@?"e
} 8^i,M^f^{
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public PaginationSupport findPageByCriteria 4>`w9
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(final DetachedCriteria detachedCriteria, finalint Q[tz)99~
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pageSize, <_uv!N
finalint startIndex){ k
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return(PaginationSupport) :8T@96]P
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getHibernateTemplate().execute(new HibernateCallback(){ RM$S|y{L
publicObject doInHibernate ~h|L;E"
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(Session session)throws HibernateException { I65GUX#DV
Criteria criteria = :\We =oX
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detachedCriteria.getExecutableCriteria(session); (I
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int totalCount = c3-bn #
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((Integer) criteria.setProjection(Projections.rowCount e{S`iO
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()).uniqueResult()).intValue(); h8;"B
criteria.setProjection Mt0|`=64
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(null); mt7:`-
List items = Hb4rpAeP
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criteria.setFirstResult(startIndex).setMaxResults k Er7,c
EatDT*!
(pageSize).list(); e#{L~3
PaginationSupport ps = xSZw,
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new PaginationSupport(items, totalCount, pageSize, qILr+zH
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startIndex); $nWmoe)
return ps; aS2
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} B9\o:eY
}, true); _bsfM;u.%
} %VZ\4+8S
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public List findAllByCriteria(final ](pD<FfS]'
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DetachedCriteria detachedCriteria){ TA5M4r6
return(List) getHibernateTemplate X_2I4Jz]6
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().execute(new HibernateCallback(){ nK$m:=
publicObject doInHibernate H*IoJL6
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(Session session)throws HibernateException { :=@[FXD4
Criteria criteria = zvWQ&?&o2
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detachedCriteria.getExecutableCriteria(session); h Bw~l?G
return criteria.list(); iV=#'yY
} uOx$@1v,
}, true); f5v|}gMAX
} %iNDRLR%I
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public int getCountByCriteria(final k:.c(_2M
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DetachedCriteria detachedCriteria){ U_?RN)>j
Integer count = (Integer) ] $*cmk(Y
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getHibernateTemplate().execute(new HibernateCallback(){ {3>^nMv@e
publicObject doInHibernate AJ /_l;
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(Session session)throws HibernateException { 60Z)AQs;+J
Criteria criteria = HT'dft #
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detachedCriteria.getExecutableCriteria(session); W~4|Z=f
return &!=3Fbn
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criteria.setProjection(Projections.rowCount y[vjqfdmU
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()).uniqueResult(); 6Jm4?ex
} ,LvJ'N
}, true); Vz^:|qON
return count.intValue(); ]!QeJ'BLM
} q b'ka+X
} K67x.P Z
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用户在web层构造查询条件detachedCriteria,和可选的 Jad'8}0J
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2yNlQP8%
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PaginationSupport的实例ps。 YG% Zw
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ps.getItems()得到已分页好的结果集 h*Ej}_
ps.getIndexes()得到分页索引的数组 hOV+}P6
ps.getTotalCount()得到总结果数 3,GSBiK3}
ps.getStartIndex()当前分页索引 OG.`\G|
ps.getNextIndex()下一页索引 h)w<{/p(
ps.getPreviousIndex()上一页索引 W[YtNL;
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,}NG@JID
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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 7BC9cS(0w9
#xO`k1W.
一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: iVFnt!
2 `#|;x^<
首先,为了实现分页查询,我封装了一个Page类: Y}0 - &
java代码: hM;E UWv
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/*Created on 2005-4-14*/ 3T_-_5[c
package org.flyware.util.page; }JI5,d
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/** R^D~ic
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* @author Joa *?c~7ru
* JAgec` T%
*/ GU=h2LSi]
publicclass Page { [}FP_Su$6
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/** imply if the page has previous page */ ek.L(n,J|
privateboolean hasPrePage; ;]p#PNQ0
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/** imply if the page has next page */ /H\ZCIu/7
privateboolean hasNextPage; Nz2}Ma 2
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/** the number of every page */ ?L|@{RS{|
privateint everyPage;
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/** the total page number */ !j\yt
privateint totalPage; I 5
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/** the number of current page */ HgbJsv$
privateint currentPage; WWD\EDnS
~aBALD0D;
/** the begin index of the records by the current a
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query */ 8^+Qn/b_%
privateint beginIndex; R\6#J0&Y-
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/** The default constructor */ : wb\N'b
public Page(){ 7HFw*;
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} I/fERnHM/+
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/** construct the page by everyPage cLX~NPD/
* @param everyPage 4uD!-1LT@
* */ UtY<R
public Page(int everyPage){ I 8e{%PK
this.everyPage = everyPage; Gu9Ap<>!
} . [*6W.X
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/** The whole constructor */ c!E+&5|n
public Page(boolean hasPrePage, boolean hasNextPage, V&[|%jm&
J/WPffqD
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int everyPage, int totalPage, 'lg6<M%#[
int currentPage, int beginIndex){ 'd'*4 )]k
this.hasPrePage = hasPrePage; & Z*&&
this.hasNextPage = hasNextPage; q=Q5s?sQc
this.everyPage = everyPage; /id(atiF^
this.totalPage = totalPage; Lw1~$rZg
this.currentPage = currentPage; NgQ {'H[Y
this.beginIndex = beginIndex; ,,lrF.
} 2Q0fgH2
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/** `+{|k)2B
* @return 9Iy>oV
* Returns the beginIndex. szGp<xv_p
*/ mi6<;N2w|
publicint getBeginIndex(){ =X]$J@j
return beginIndex; e%u1O-*
} >ouHR*
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/** {H=DeQ
* @param beginIndex vrLI`3n]
* The beginIndex to set. H<Ed"-n$I<
*/ xOp8[6Ga'
publicvoid setBeginIndex(int beginIndex){ ;gP@d`s
this.beginIndex = beginIndex; $x)C_WZj?
} DgGGrV`
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/** wspZ Eu>C;
* @return LSs!U
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* Returns the currentPage. YP5V~-O/
*/ 2aNCcZw0
publicint getCurrentPage(){ vdyLwBz:
return currentPage; Mnn\y Tblp
} UMuRB>ey
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/** MDM/~Qpj_
* @param currentPage z
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* The currentPage to set. 3){ /u$iH.
*/ -U`]/
publicvoid setCurrentPage(int currentPage){ }uz*6Z(S
this.currentPage = currentPage; _e
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} w)2X0ev"
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/** Y&6vTU
* @return eZ'J,;
* Returns the everyPage. no~hYyW2
*/ RP?UKOc
publicint getEveryPage(){ {9S=:
return everyPage; wi-O}*O
} |gxT-ZM
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/** kC"lO'
* @param everyPage @8a1a3_F
* The everyPage to set. EZlcpCS
*/ ;'CWAJK
publicvoid setEveryPage(int everyPage){ PQ9.aJdw@-
this.everyPage = everyPage; yhhW4rz
} T1sb6CT
,<!_MNw[
/** 8VxjC1v+
* @return ?0QoYA@.$
* Returns the hasNextPage.
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*/ MhaN+N
publicboolean getHasNextPage(){ d}#G~O+y3v
return hasNextPage; +0lvQVdp}
} MLf,5f;e
gb:)t}|
/** 9)N/J\b
* @param hasNextPage sz4)xJgF(
* The hasNextPage to set. V bQ9o
*/ jLRUWg
publicvoid setHasNextPage(boolean hasNextPage){ )xwWig.
this.hasNextPage = hasNextPage; o0t/
} .b'hVOs{
"9mJ$us
/** <4V]>[{W
* @return ^wDZg`
* Returns the hasPrePage. yf5X=f.%@
*/ PO9<g%qTf
publicboolean getHasPrePage(){ doM}vh)6
return hasPrePage; N]qX^RSb
} (NPDgR/
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/** rWk4)+Tk
* @param hasPrePage 9;,_Qq
* The hasPrePage to set. Rf7*Ut
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*/ aI @&x
publicvoid setHasPrePage(boolean hasPrePage){ GjF'03Z4
this.hasPrePage = hasPrePage; ,#;%ILF4%
} P){F2&!P
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/** uEp
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* @return Returns the totalPage. M`{x*qR
* 1~X~"M
*/ B1\@ n$
publicint getTotalPage(){ w
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return totalPage; O}VI8OB(&
} ]u~6fknm
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/** nFE0y3GD8
* @param totalPage i^hgs`hvU
* The totalPage to set. sR%,l
*/ K.CwtUt`54
publicvoid setTotalPage(int totalPage){ b.Wf*I?
this.totalPage = totalPage; c o}o$}
} 7vBB <\
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} |UbwPL_L
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 WgBV,{C
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个PageUtil,负责对Page对象进行构造: i,G )kt'H
java代码: ((BuBu>
jtWI@04o09
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/*Created on 2005-4-14*/ _SS6@`X
package org.flyware.util.page; u#tLY/KA
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import org.apache.commons.logging.Log; dm4dT59
import org.apache.commons.logging.LogFactory; i2<dn)K[~-
m<ZwbD
/** XWo=?(iA
* @author Joa muSQFIvt
* ,nMc.
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*/ V0p@wG3
publicclass PageUtil { 8.vPh
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privatestaticfinal Log logger = LogFactory.getLog E|2klA^+*
z_XI,u}
(PageUtil.class); -B\`O*Q
=Ewa}$-
/** d OY+| P\
* Use the origin page to create a new page MmOGt!}9A
* @param page H9)$ #r6i
* @param totalRecords 64s9Dy@%F
* @return Q$iGpTL
*/ }-{l(8-
publicstatic Page createPage(Page page, int B1@c`BJ;9T
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totalRecords){ '{EBK
return createPage(page.getEveryPage(), 7M:0%n$
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page.getCurrentPage(), totalRecords); 8xUmg&
} Rs;,_
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/** /Ny/%[cu
* the basic page utils not including exception F'ZLN]"{
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handler wxPg*R+t
* @param everyPage Dbr(Wg
* @param currentPage FE1dr_i
* @param totalRecords Y=/3_[G
* @return page 1p,G8 v+B
*/ 'w.:I
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publicstatic Page createPage(int everyPage, int 57+^T}/>
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currentPage, int totalRecords){ De|@}@
everyPage = getEveryPage(everyPage); >fo &H_a
currentPage = getCurrentPage(currentPage); e*vSGT$KgL
int beginIndex = getBeginIndex(everyPage, (J Fa
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currentPage); iZ[o2Tre
int totalPage = getTotalPage(everyPage, ^~MHxF5d
URR|Q!D
totalRecords); N|q:wyS|
boolean hasNextPage = hasNextPage(currentPage, qd3B>f
zE.4e&m%Z?
totalPage); {NE;z<,*:
boolean hasPrePage = hasPrePage(currentPage); 9>le-}~
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returnnew Page(hasPrePage, hasNextPage, >C_! }~
everyPage, totalPage, f%*-PW^*
currentPage, ]-{T-*h:
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beginIndex); CNcH)2Mk
} wb 4 4
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privatestaticint getEveryPage(int everyPage){ vWfC!k-)b
return everyPage == 0 ? 10 : everyPage; iO#H_&L.p
} /[nt=#+
GLc+`,.
privatestaticint getCurrentPage(int currentPage){ f{ S)wE>;
return currentPage == 0 ? 1 : currentPage; p fAp2"
} 40%p
lNPj
? dSrY
privatestaticint getBeginIndex(int everyPage, int X+iA"B
[W{`L_"
currentPage){ R52q6y:<x
return(currentPage - 1) * everyPage; )IZ$R*Y{
} Y<#7E;aL
Kt}dTpVFr
privatestaticint getTotalPage(int everyPage, int `p1`Sxz?
*o"F.H{#N
totalRecords){ aKCCFHq t!
int totalPage = 0; "P<~bw5
|Z 3POD"9
if(totalRecords % everyPage == 0) f.+e
totalPage = totalRecords / everyPage; nk-6W4
else d:sUh
totalPage = totalRecords / everyPage + 1 ; 2b|vb}|t{
wK#UFOp
return totalPage; -ZihEyG?V
} B0Z*YsbXL
DU1,i&(
privatestaticboolean hasPrePage(int currentPage){ 5-u=ZB%p
return currentPage == 1 ? false : true; 62vz 'b
} *QLl
jGe
,u]kZ ]
privatestaticboolean hasNextPage(int currentPage, OgH Wmb
Vi#(x9.
int totalPage){ H`@x5RjS
return currentPage == totalPage || totalPage == >Ckb9A
Za}91z"
0 ? false : true; yx/:<^"-$
} X#eVw|
TR)'I
de ](l687I
} |u;5|i
2N)vEUyDV
7%w4?Nv3I
Wdy2;a<\{
mbS
&>
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。 M>I}^Zp!
89 (k<m
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 s_1]&0<
yobi$mnsy!
做法如下: Lwv9oa|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 _&w!JzpXT
H
uE*jQ
的信息,和一个结果集List: 80+"
x3r
java代码: N+}yw4lb
*2@q=R-1
-@#AQ\
/*Created on 2005-6-13*/ ied<1[~S
package com.adt.bo; .)W8
U [
|`O7>(h
import java.util.List; l_}c[bAUu
((?^B
import org.flyware.util.page.Page; Jn:GqO
,g\.C+.S
/** zSq+#O1#
* @author Joa e94csTh=
*/ ul% q6=f)
publicclass Result { $!fz87-p>
U\b,W&%P
private Page page; a{u)~:/G
PqP)<d'/
private List content; v=X\@27= ?
~^3B(feQ]
/** K, 35*
* The default constructor !J6k\$r
*/ 8"S0E(,mu
public Result(){ +$<m ;@mZ
super(); *~-~kv4-
} u|w[b9^r
Ig9$ PP+3
/** fCF9 3,?$
* The constructor using fields OY@/18D<>
* l5@k8tnz
* @param page $T*kpUXH}
* @param content s=KA(4p
*/ sa*hoL18
public Result(Page page, List content){ IXC: Q
this.page = page; 46$5f?Z
this.content = content; _/PjeEm
$p
} 8~4{e,} ,
]C'r4Ch^
/** EnfSVG8kB8
* @return Returns the content. E7 7Au;TL
*/ Pw+cpM8<
publicList getContent(){ =k &'ft
return content; $)PNf'5Zg
} R2r0'Yx
i #8)ad
/** &}*[-z
* @return Returns the page. gIT"nG=a4
*/ ON!1lS
public Page getPage(){ ^#_@Kq%th
return page; n.Ekpq\
} 1k;X*r#
Plt~l3_
/** sx|=*j,_
* @param content O~igwFe
* The content to set. `@eQL[Z9x
*/ edbzg#wy
public void setContent(List content){ EXo"F*gW
this.content = content; :5p`H
} Uv.{=H:
[{'` |
/** EK[~lIXg
* @param page OCF=)#}qd
* The page to set. X(N!y"z
*/ fF<~2MiKw
publicvoid setPage(Page page){ k`xPf\^tf
this.page = page; j].XVn,
} gh3_})8c
} 0(HUy`]>
'BtvT[KM
`Y8F}%i[
A)'{G
| [P!9e
2. 编写业务逻辑接口,并实现它(UserManager, ig jr=e
Un@d Wf6'
UserManagerImpl) zGA1
java代码: CO-9-sQx
_-^a8F>/19
r
",..{
/*Created on 2005-7-15*/ 8FU8E2zo
package com.adt.service; o yK'h9Wt1
PA&Ev0`+
import net.sf.hibernate.HibernateException; GK~uoz:^O
o4\\q66K
import org.flyware.util.page.Page; 'HzF/RKh
iTwb#Q=
import com.adt.bo.Result; 4ba[*R2
/&_$+Iun
/** J>TNyVaoQ
* @author Joa nD{o8;
*/ lvY[E9I0
publicinterface UserManager { WBK6Ug
4hz T4!15
public Result listUser(Page page)throws X @RS
/
SFv'qDA
HibernateException; +DU^"q=
SYkwM6
} l|9'M'a
8BE] A_X
nm Y_ )s
T\?$7$/V
0Ta&o-e
java代码: 9sG]Q[:.]
%PM&`c98z7
SMoJKr(:w#
/*Created on 2005-7-15*/ \2)D
package com.adt.service.impl; 70Jx[3vr
G!dx)v
import java.util.List; ^F,sV*
KW-GVe%8f
import net.sf.hibernate.HibernateException; =HMa<"-8
,.9k)\/V
import org.flyware.util.page.Page; mX 3p
import org.flyware.util.page.PageUtil; ZP{<f~;
DK)T2{:
import com.adt.bo.Result; 5(>SFxz"t
import com.adt.dao.UserDAO; }D># AFs6#
import com.adt.exception.ObjectNotFoundException; P q0%oz
import com.adt.service.UserManager; ja^_Lh9
Yw] 7@
/**
b:Z&;A|"{
* @author Joa @`$'sU
*/ Jvc:)I1NE7
publicclass UserManagerImpl implements UserManager { TyDh\f!w
Z_Wzm!:
private UserDAO userDAO; ]Hp>~Zvbb
@A4$k
dJ2
/** &AN1xcx\
* @param userDAO The userDAO to set. w4(L@1
*/ '2GnA ws^
publicvoid setUserDAO(UserDAO userDAO){ CP~mKmMV
this.userDAO = userDAO; _%q~K (::
} pO_IUkt
? D
_kQl
/* (non-Javadoc)
C];P yQS
* @see com.adt.service.UserManager#listUser ],_+J*
SE'!j]6jI
(org.flyware.util.page.Page) AdVc1v&>
*/ nl
qn:[BU
public Result listUser(Page page)throws =:aJZ[UU<2
@/F61Ut
HibernateException, ObjectNotFoundException { m>%b4M
int totalRecords = userDAO.getUserCount(); >))CXGE
if(totalRecords == 0) s3HVX'
throw new ObjectNotFoundException rUpe ;c
fqhL"Ah
("userNotExist"); o:D,,MkSw
page = PageUtil.createPage(page, totalRecords); zw['hqW
List users = userDAO.getUserByPage(page); 3V<@Vkf5
returnnew Result(page, users); I]^>>>p$
} tLBtE!J$[
HcgvlFb
} )rq |t9kix
&W,jR|B
5?lc%,-&
;%9]G|*{
#L~i|(=U5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 CuWJai:nQ;
&^r>Q`u
询,接下来编写UserDAO的代码: gxN>q4z
3. UserDAO 和 UserDAOImpl: J0?kEr
java代码: N7?B"p/
hbJ>GSoZ,
q0iJy@?A
/*Created on 2005-7-15*/ N-gYamlQ
package com.adt.dao; |;vQ"8J
<7M-?g:vj
import java.util.List; <eoie6@3
L=l&,ENy
import org.flyware.util.page.Page; d~Z\%4
c2y,zq|H
import net.sf.hibernate.HibernateException; &EfQ%r}C
"2l`XH
/** KwuucY
* @author Joa CIjc5^Y2
*/ 1^!SuAA@
publicinterface UserDAO extends BaseDAO { [d: u(
|_V(^b}
publicList getUserByName(String name)throws K:wI'N"N
FEaT}/h;
HibernateException; *yu}e)(0
WMSJU/-P
publicint getUserCount()throws HibernateException; AcC &Q:g
ffZ~r%25{
publicList getUserByPage(Page page)throws XBQt:7[<
!+eH8
HibernateException; S/nPK,^d2
iwotEl0*{
}
c0oHE8@
LQ jbEYp
YmziHns`b
OT9]{|7
Zw.8B0W
java代码: ]~({;;3o-
(W
~K1]
/yOx=V
/*Created on 2005-7-15*/ 1E+12{~m"i
package com.adt.dao.impl; lW+mH=
N3%X>*'
import java.util.List; [#PE'i4
M]x>u@JH
import org.flyware.util.page.Page; {.p.?
A,}M ^$@
import net.sf.hibernate.HibernateException; eS`VI+=@0
import net.sf.hibernate.Query; =]Wi aF
0MG>77
import com.adt.dao.UserDAO; 1Kg0y71"
a`xq
h2P
/** X8nos
* @author Joa ekM?
'9ez
*/ dY*q[N/pO
public class UserDAOImpl extends BaseDAOHibernateImpl RB 5SK#z
Harg<l
implements UserDAO { ^L[:DB{Z
3H,E8>Vd
/* (non-Javadoc) +iVEA(0&$
* @see com.adt.dao.UserDAO#getUserByName oQ!M+sRmF
8>Cr6m
(java.lang.String) YH&=cI@
*/ J K
k0f9)
publicList getUserByName(String name)throws uqMw-f/
([>ecS@eO
HibernateException { k]b*&.EY1
String querySentence = "FROM user in class iI3:<j
l
8nz({Mb9Z
com.adt.po.User WHERE user.name=:name"; dmFn0J-\
Query query = getSession().createQuery i"8mrWb
FFHq':v
(querySentence); !l:GrT8J
query.setParameter("name", name); odRiCiMH
return query.list(); Shn,JmR
} VYvfx
9&6j uL
/* (non-Javadoc) d*(aue=
* @see com.adt.dao.UserDAO#getUserCount() dG\wW@}J
*/ 8{ zX=
publicint getUserCount()throws HibernateException { !Ok(mgV$/
int count = 0; f5jl$H.
String querySentence = "SELECT count(*) FROM _z\/{
;b~ S/
user in class com.adt.po.User"; bJ^JK
Query query = getSession().createQuery 0-2|(9
Kc
Zt=|q$"
(querySentence); ua\t5M5
count = ((Integer)query.iterate().next mH*ldf;J;=
m[hL
GD'Fi
()).intValue(); E$8JrL
return count; TP }a9-9?
} . [|UNg
Xn7G2Yp
/* (non-Javadoc) 0;Z|:\P\=
* @see com.adt.dao.UserDAO#getUserByPage RObnu*
9 {4yC9Oz>
(org.flyware.util.page.Page) c-Lz luWi
*/ /y$Omc^
publicList getUserByPage(Page page)throws .RD<]BxJ
wxN)dB
HibernateException { J<)qw
String querySentence = "FROM user in class eUPa5{P
]#!uke Q
com.adt.po.User"; @]\fO)\f
Query query = getSession().createQuery nt.LiM/L
H]TdW;ZbZ
(querySentence); l|5 h
query.setFirstResult(page.getBeginIndex()) 1S{Biqi+
.setMaxResults(page.getEveryPage());
#]#9Xq
return query.list(); 9A.RD`fg
} X/_I2X
$|4@Zx4vf
} 7qKz_O
?R`S-
bcIae0LZ
eJDZ|$
| /.J{=E0K
至此,一个完整的分页程序完成。前台的只需要调用 ,'L>:pF3
i~B?p[
userManager.listUser(page)即可得到一个Page对象和结果集对象 G gO5=|
W4$o\yA]
的综合体,而传入的参数page对象则可以由前台传入,如果用 {Jr1K,
A40DbD\^ad
webwork,甚至可以直接在配置文件中指定。 F72#vS
j
_&KqmQ8$7
下面给出一个webwork调用示例:
:e1h!G
java代码: H MOIUd
P^Hgm
\;;M")$
/*Created on 2005-6-17*/ b,!C8rJ
package com.adt.action.user; ]m1fo'
!2!~_*sGe
import java.util.List; 5epI'D
_~FfG!H ^X
import org.apache.commons.logging.Log; n Ja!&G&
import org.apache.commons.logging.LogFactory; BR|!ya+_2
import org.flyware.util.page.Page; g)Z8WH$;H3
X$};K\I
import com.adt.bo.Result; y<`5
import com.adt.service.UserService; pwSgFc$z
import com.opensymphony.xwork.Action; RB>=#03
X'A`"}=_
/** -sJ1q^;f@
* @author Joa et5lfj
*/ |ufL s
publicclass ListUser implementsAction{ LqYyIbsvf
x8aOXN#w}
privatestaticfinal Log logger = LogFactory.getLog <ll?rPio"
Uha.8
(ListUser.class); % PzkV s
Q
z(n41@`
private UserService userService; lU
62$2
j-d&4,a:c
private Page page; c:7V..
}E ]l4N2
privateList users; %%ouf06.|
%|JiFDjp
/* #M|lBYdW}
* (non-Javadoc) p#jAEY p
* /V 09Na,N
* @see com.opensymphony.xwork.Action#execute() rmzzbLTu
*/ ld]*J}cw
publicString execute()throwsException{ 7:olStK
Result result = userService.listUser(page); MrB#=3pT
page = result.getPage(); m[xl)/e
users = result.getContent(); beo(7,=&
return SUCCESS; V3ht:>c9qs
} Ez~5ax7x
oaqH@`
/** pDlrK&;\z
* @return Returns the page. ,B'=$PO%
*/ uCr& `
public Page getPage(){ #dae^UjM
return page; OJpfiZ@Q_
} 1l$C3c
AwNr}9`
/** 3!l>\#q6
* @return Returns the users. qZ^
PC-
*/ "jyo'r
publicList getUsers(){ ={;pg(
return users; y#B=9Ri=z
} KV$&qM.
'(@q"`n
/** ':pDlUA
* @param page iY/2 `R
* The page to set. =KHb0d |.
*/ ~Pw9[ycn3
publicvoid setPage(Page page){ 0\XWdTj{
this.page = page; **%&|9He
} ]6B9\C.2-_
f;^ +q-Q
/** V?S}%-a
* @param users ~'%d]s+q
* The users to set. jKmjZz8L]%
*/ F2}Fuupb.
publicvoid setUsers(List users){ (|<S%?}J
this.users = users; i'li;xUhZ
} -c&=3O!
se %#U40*
/** `[5xncZ-
* @param userService GKIzU^f
* The userService to set. g7]S
*/ sPi
publicvoid setUserService(UserService userService){ `f}s<At
this.userService = userService; "b`#RohCi
} E2r5Pg
} 1ARtFR2C{b
39 }e
}W"
S. `y%t.GP
LSc^3=X
_MC',p&
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, ]Ik~TW&
;GM`=M4
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 Hj>9 #>b
}PK4
KRn
么只需要: 5z0Sns
java代码: ivgX o'=
y_Lnk=Q ^
RL4|!HzR
<?xml version="1.0"?> u;$qJjS
N
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork c9[{P~y
dY}5Kmt
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \@Cz 32wg
Ne+Rs+~4
1.0.dtd"> aQmS'{d?^
X'$H'[8;C
<xwork> } 9zi5o8
9ad)=3A&L
<package name="user" extends="webwork- k?7"r4Vc)S
D,.`mX
interceptors"> poafGoH-Y
h!dij^bD
<!-- The default interceptor stack name +ZjDTTk
&I-:=ir
--> z{3`nd,
<default-interceptor-ref 9`92
>
-%J9!(
name="myDefaultWebStack"/> %TI3Eb
A v>v\ :.>
<action name="listUser" Os[z>H?
-_9*BvS]R
class="com.adt.action.user.ListUser"> OH>Gc-V
<param Me z&@{
&V
axv$v}
name="page.everyPage">10</param> W[I[Xg&
<result VTL_I^p
O\Y*s
name="success">/user/user_list.jsp</result> =A,T:!}'
</action> r Yt|[Pk
*Jcd_D\-(1
</package> |(tl
a_LE
x$jLB&+ICz
</xwork> g
\S6>LG!
L %ac sb}
S^~"#
el$@^Wy&$
i;~.kgtq4
Ge=6l0
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 &^&0,g?To
9?sY!gXc
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。 gcwJ{&
9E5*%Hu_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 y)|d`qC\
IIMf\JdM
/Cwwz
LR.]&(kyd
%Qj$@.*:
我写的一个用于分页的类,用了泛型了,hoho <J~6Q
])qnPoQ<n
java代码: IN6L2/Q
CEkf0%YJ
,e 7
~G
package com.intokr.util; dL'oIBp
bRFZ:hu l
import java.util.List; ]7,0>
kn$SG
/** 66B,Krz1n
* 用于分页的类<br> {pXX%>
* 可以用于传递查询的结果也可以用于传送查询的参数<br> mK7SEH;
* ORX<ZOt1
* @version 0.01 Qg1kF^=
* @author cheng k=d_{2 ~
*/ !}mM"|<
public class Paginator<E> { jN=
!Q&^i[
privateint count = 0; // 总记录数 \{*`-Pv
privateint p = 1; // 页编号 r;(^]Soz
privateint num = 20; // 每页的记录数 LD WYFOGQ
privateList<E> results = null; // 结果 lGT[6S\as
:zIB3nT^
/** 4Af7x6a;
* 结果总数 HYdt3GtJ?
*/ ou)0tX3j
publicint getCount(){ :Eg4^,QX
return count; mm!JNb9(
} ZZ}HgPZ
phA{jJy?
publicvoid setCount(int count){ 4%yeEc;z
this.count = count; bB/fU7<{)u
} {P?p*2J'
AKLFUk
/** Y2uy@j*N
* 本结果所在的页码,从1开始 6~!7?FK
* nYC S %\"
* @return Returns the pageNo. %,8
"cM`D
*/ LDo~
publicint getP(){ j}}as
return p; qpf|.m
} $Vs5d=B
@v6{U?
/** sx[mbKj<
* if(p<=0) p=1 h=au`o&CG
* F CfU=4O
* @param p Cw.DLg
*/ 1X&scVw
publicvoid setP(int p){ \Z/0i|
if(p <= 0) 8"wavh|g4
p = 1; ^D
{v L
this.p = p; @-1VN;N
} `9f7H
6l|SGt\
/** '<C#"2
* 每页记录数量 bHs},i6
*/ l2!ztK1^
publicint getNum(){ *ES"^N/88
return num; :N4?W}r.
} dlV HyCW
RL"hAUs_1
/** Zq/=uB7Z
* if(num<1) num=1 ~05(92bK
*/ @A%\;oo
publicvoid setNum(int num){ .X4UDZQg
if(num < 1) 59_VC('
num = 1; gEq";B%?
this.num = num; p!LaR.8]
} 4Z{ r
wqQrby<
/** LgSVEQb6\|
* 获得总页数 5[+E?4,&
*/ =:^f6"p&Z
publicint getPageNum(){ WWIQ6EJO
return(count - 1) / num + 1; M ~6k[ew
} `uqsYY`V
+d8?=LX
/** 5[$Tpn#K7
* 获得本页的开始编号,为 (p-1)*num+1 -hO[^^i9
*/ lJ4&kF=t
publicint getStart(){ ]K>x:vMKH
return(p - 1) * num + 1; URxy*)
} EDGAaN*Q
m-|~tve
/** l$!g#?w
* @return Returns the results. :P\RiaZAT
*/ x4S0C[k
publicList<E> getResults(){ 'y:+w{I2o
return results; JiHk`e`
} G2_l}q~
x;>~;vmi
public void setResults(List<E> results){ qRA,-N
this.results = results; =M/($PA
} ,OaPrAt-
C'//(gjQ-G
public String toString(){ 1ml{oqNj
StringBuilder buff = new StringBuilder pr"~W8
Z^vcODeC$
(); ]bb`6 \h
buff.append("{"); VZ$FTM^b8
buff.append("count:").append(count); `Ot;KDz
buff.append(",p:").append(p); #Q_
d
buff.append(",nump:").append(num); E6y ?DXWH
buff.append(",results:").append &o*f*(C2
G~Mxh,aD$>
(results); M8'
GbF=1
buff.append("}"); xs3t~o3y
return buff.toString(); d<^o@
} aY@st]p
j; )-K 3Ia
} }CXL\,;
9-?[%8
T*sB Wn'am