Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3 {$vN).
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <aztbq?
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 >3ax `8
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 @`$'sU
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分页支持类: L4,b ThSG
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java代码: Q2/65$nW
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package com.javaeye.common.util; B*Q 9g r
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import java.util.List; Z1#u&oX
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publicclass PaginationSupport { <d @9[]
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publicfinalstaticint PAGESIZE = 30; $=iw<B r
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privateint pageSize = PAGESIZE; jp_|pC'
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privateList items; #x;,RPw5
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privateint totalCount; \yl|*h3
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privateint[] indexes = newint[0]; !_vxbfZO
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privateint startIndex = 0; `^52IkM)
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public PaginationSupport(List items, int Y{D%v
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totalCount){ Z:dp/M}
setPageSize(PAGESIZE); P #O2MiG
setTotalCount(totalCount); f(Y_<%
setItems(items); k,[*h-{8
setStartIndex(0); >))CXGE
} t;BUZE_!0c
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public PaginationSupport(List items, int T]ls&cW5
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totalCount, int startIndex){ "$XX4w
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setPageSize(PAGESIZE); lDTHK2f
setTotalCount(totalCount); ,Cb3R|L8
setItems(items); 12a`,~
setStartIndex(startIndex); yL*]_
} gs5(~YiT6
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public PaginationSupport(List items, int } vmRm*8z
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totalCount, int pageSize, int startIndex){ ;eN
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setPageSize(pageSize); &W,jR|B
setTotalCount(totalCount); yEq7ueJ'
setItems(items); K#YQB3rX
setStartIndex(startIndex); .^?zdW
} $P=C7;
*!%lBt{2
publicList getItems(){ U}LW8886
return items; =eDIvNps
} EHk\Q\
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publicvoid setItems(List items){ DsejZ&
this.items = items; lG}#K^q
} H/c
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publicint getPageSize(){ Iko]c_W0
return pageSize; Ttt'X<9
} V5w1ET
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publicvoid setPageSize(int pageSize){ $@>0;i::
this.pageSize = pageSize; u.ggN=Z
} BDTL5N
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publicint getTotalCount(){ );$99t
return totalCount; TaN{xpo
} /8FmPCp}r
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publicvoid setTotalCount(int totalCount){ O$<>v\NC?
if(totalCount > 0){ :OG I|[
this.totalCount = totalCount; iQ;p59wSzL
int count = totalCount / KwuucY
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pageSize; {_QdB;VwH
if(totalCount % pageSize > 0) 1u
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count++; '+`[)w
indexes = newint[count]; ;V
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for(int i = 0; i < count; i++){ BmG(+;;&
indexes = pageSize * QO2cTk
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i; q` q;og
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} rO'DT{Yt
}else{ 5~L]zE
this.totalCount = 0; 9
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} ffZ~r%25{
} 5E&#Kh(I
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publicint[] getIndexes(){ _)M,p@!?=h
return indexes; F$C6( C?
} T5(S2^)o
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publicvoid setIndexes(int[] indexes){ Vw;Z0_C
this.indexes = indexes; '<R>cN"
} R4m{D
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publicint getStartIndex(){ Zt `Tg7m
return startIndex; i[v4[C=WB!
} hF%M!otcJ-
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publicvoid setStartIndex(int startIndex){ KK){/I=z
if(totalCount <= 0) Fx9-A8oIR
this.startIndex = 0; ZK5nN9`
elseif(startIndex >= totalCount) ?sf<cFF
this.startIndex = indexes 1E+12{~m"i
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[indexes.length - 1]; gcJ!_KZK
elseif(startIndex < 0) $[ {5+ *
this.startIndex = 0; g7 \=
else{ mdj%zJ8/
this.startIndex = indexes
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[startIndex / pageSize]; {.p.?
} /jY
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} Yj%]|E-
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publicint getNextIndex(){ ]&cnc8tC
int nextIndex = getStartIndex() + '![oLy
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pageSize; !"rPSGK*
if(nextIndex >= totalCount) xa>| k>I
return getStartIndex(); =>jp\A
else J:xGEa t
return nextIndex; B,%Vy!o
} dY*q[N/pO
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publicint getPreviousIndex(){ @60D@Y
int previousIndex = getStartIndex() - sV\_DP/l
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pageSize; *l2`- gbE
if(previousIndex < 0) c8l>OS5i3_
return0; j4.wd
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else +iVEA(0&$
return previousIndex; fz&B$1;8
} OQVrg2A%(
}9~^}99}
} I6>J.6luF9
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抽象业务类 uqMw-f/
java代码: $[gN#QW%
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/** /:{%X(8
* Created on 2005-7-12 O'y8q[2KE
*/ i+_LKHQN
package com.javaeye.common.business; SQKhht`M
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import java.io.Serializable; ]%Q!%uTh
import java.util.List; k6G
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import org.hibernate.Criteria; ?#xl3Z ;I
import org.hibernate.HibernateException; sX>u.
import org.hibernate.Session; ;nY#/%f
import org.hibernate.criterion.DetachedCriteria; =2Y;)wrF
import org.hibernate.criterion.Projections; Shn,JmR
import ><V*`{bD9)
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org.springframework.orm.hibernate3.HibernateCallback; O%bbyR2
import F3tps
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org.springframework.orm.hibernate3.support.HibernateDaoS SN{z)q
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upport; H;H=8'
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import com.javaeye.common.util.PaginationSupport; baxZ>KNi
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public abstract class AbstractManager extends dC11kqqj
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HibernateDaoSupport { /d`"WK,
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privateboolean cacheQueries = false; fgLjF,Y
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privateString queryCacheRegion; / 3A6xPOg
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publicvoid setCacheQueries(boolean OM*_%UF
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cacheQueries){ &C 9hT
this.cacheQueries = cacheQueries; 3h@]cWp
} FDHW'OP4
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publicvoid setQueryCacheRegion(String LPk@t^[
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queryCacheRegion){ Kxe\H'rR
this.queryCacheRegion = G\.~/<Mg+
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queryCacheRegion; Xn7G2Yp
} C2
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publicvoid save(finalObject entity){ a#oROb-*~
getHibernateTemplate().save(entity);
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} rp Nb.
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publicvoid persist(finalObject entity){ [ks_wvY:'
getHibernateTemplate().save(entity); /y$Omc^
} hor7~u+
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publicvoid update(finalObject entity){ bIQ,=EA1
getHibernateTemplate().update(entity); x4_IUIgh
} .)Tj}Im2p
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publicvoid delete(finalObject entity){ v.0qE}'
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getHibernateTemplate().delete(entity); ]#!uke Q
} ((y|?Z$
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publicObject load(finalClass entity, Fs+tcr/\[
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finalSerializable id){ GP:<h@:798
return getHibernateTemplate().load xtV+Le%
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(entity, id); +UzQJt/>>
} Y&|Z*s+
+}
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publicObject get(finalClass entity, bR\7j+*&
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finalSerializable id){ [W[{
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return getHibernateTemplate().get bS_#3T
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(entity, id); (vXr2Z<l
} Sp`l>BL
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publicList findAll(finalClass entity){ ycA<l"
return getHibernateTemplate().find("from PKm|?kn{0(
$l.*;h *
" + entity.getName()); qwTz7r
} i~B?p[
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publicList findByNamedQuery(finalString 0G%9
@^B
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namedQuery){ 5Xy(za
return getHibernateTemplate ;(Yb9Mr)z
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().findByNamedQuery(namedQuery); =SDex.ZK]
} 7h'
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publicList findByNamedQuery(finalString query, >w,L= z=
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finalObject parameter){ 7iB!Uuc
return getHibernateTemplate C6+ 5G-Z
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().findByNamedQuery(query, parameter); YAi-eL67l
} {v={q1
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publicList findByNamedQuery(finalString query, kHM Jh~
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finalObject[] parameters){ 0uy'Py@2<
return getHibernateTemplate # :+Nr
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().findByNamedQuery(query, parameters); z/?* h
} "2%z;!U1
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publicList find(finalString query){ zLJ>)v$81
return getHibernateTemplate().find `kKssU<
8}%F`=Y0
(query); =vThtl/azD
} c[@_t.%)
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publicList find(finalString query, finalObject Ou[K7-m%&
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parameter){ 79DNNj~
return getHibernateTemplate().find ixTjXl2g
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(query, parameter); ]3r}>/2(
} Upz)iOqLi
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public PaginationSupport findPageByCriteria iSfRJ:_&6
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(final DetachedCriteria detachedCriteria){ U1\EwBK8*T
return findPageByCriteria 3Tr,waV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *tjaac;z<J
} @f[-
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public PaginationSupport findPageByCriteria }n)0}U5;0
fy+5i^{=
(final DetachedCriteria detachedCriteria, finalint g-3^</_fZ
+'F;\E
startIndex){ y_PA9#v7
return findPageByCriteria #N{]
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(detachedCriteria, PaginationSupport.PAGESIZE, fECV\Z
s,R:D).
startIndex); rfV'EjiM}
} |n_N.Z
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public PaginationSupport findPageByCriteria E}wT5t;u
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(final DetachedCriteria detachedCriteria, finalint !ooi.Oz*Tu
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pageSize, z+Xr2B
finalint startIndex){ ^y,h0?Z9
return(PaginationSupport) 9J:|"@)N
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getHibernateTemplate().execute(new HibernateCallback(){ 4!sK>l!
publicObject doInHibernate X5owAc6
#-|fdcb
(Session session)throws HibernateException { Z+B*V)a=
Criteria criteria = [kg^S`gc#
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detachedCriteria.getExecutableCriteria(session); Kebr>t8^
int totalCount = cb-IRGF
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((Integer) criteria.setProjection(Projections.rowCount Gf8 ^nfr
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()).uniqueResult()).intValue(); *+v*VH
criteria.setProjection >/ _#+,
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(null); 6B]=\H
List items = =
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criteria.setFirstResult(startIndex).setMaxResults GVhqNy
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(pageSize).list(); ;gBR~W
PaginationSupport ps = ?22U0UF
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new PaginationSupport(items, totalCount, pageSize, :E}y
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8SpG/gl"
startIndex); h: yJ
return ps; a~Dk@>+P>
} `h'+4
}, true); /KvJjt'8
} _Q:z -si
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public List findAllByCriteria(final YPx+9^)
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DetachedCriteria detachedCriteria){ )bM,>x
return(List) getHibernateTemplate KBM*7raA
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().execute(new HibernateCallback(){ ZK;/~9KU
publicObject doInHibernate 4T3Z9KD!8
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(Session session)throws HibernateException { (:8a6=xQ
Criteria criteria = '$Z)2fn7
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detachedCriteria.getExecutableCriteria(session); 0{vT`e'
return criteria.list(); 'v^Vg
} Xz @#,F:@
}, true); u7mPp3ZYK
} /"J 6``MV
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public int getCountByCriteria(final PVg<Ovi^d
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DetachedCriteria detachedCriteria){ ]AQ}_dRi=
Integer count = (Integer) JPn)Op6
t Cb34Wpf
getHibernateTemplate().execute(new HibernateCallback(){ 6D
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publicObject doInHibernate T9R#.y,
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(Session session)throws HibernateException { s! 2[zJ19p
Criteria criteria = T; tY7;<
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detachedCriteria.getExecutableCriteria(session); ,=\.L_'
return <Q(E {c3"
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criteria.setProjection(Projections.rowCount !`%j#bv
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()).uniqueResult(); RWv4/=}(G
} K ,NmDc^
}, true); Mv%Qze,\V^
return count.intValue(); 27 XM&ZrZ
} MlYm\x8{M
} B!pz0K*uG
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用户在web层构造查询条件detachedCriteria,和可选的 xI{fd1
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e1a\--
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PaginationSupport的实例ps。 _U&HXQ8X
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ps.getItems()得到已分页好的结果集 #M|lBYdW}
ps.getIndexes()得到分页索引的数组 o3hgkoF
ps.getTotalCount()得到总结果数 ;Tr,BfV|Bf
ps.getStartIndex()当前分页索引 5e.aTW;U
ps.getNextIndex()下一页索引 >BO$tbU5b
ps.getPreviousIndex()上一页索引 |hxiARr4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 >)<?
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一下代码重构了。 0&sa#g2
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我把原本我的做法也提供出来供大家讨论吧: +ZNOvcsV
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首先,为了实现分页查询,我封装了一个Page类: u ,3B[
java代码: W9]z]6
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/*Created on 2005-4-14*/ (a#gCG\
package org.flyware.util.page; %<-OdyM
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/** I+H~ 5zq.
* @author Joa sR1_L/.
* 5?;<^J
*/ 7tlK'j'
publicclass Page { 0\:=KIY.
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/** imply if the page has previous page */ y#B=9Ri=z
privateboolean hasPrePage; @
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/** imply if the page has next page */ {WV"]O8IV
privateboolean hasNextPage; +]cf/_8+s
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/** the number of every page */ (0.oE%B",1
privateint everyPage; ;Va(l$zD
:
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/** the total page number */ syBpF:`-W
privateint totalPage; `hO%(9V9
yF(9=z"?
/** the number of current page */ pF8$83S
privateint currentPage; -c&=3O!
)).=MTk
/** the begin index of the records by the current S'34](9n6
T;(,9>Qsu
query */ dh`s^D6Q>
privateint beginIndex; e#Ao]gc
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/** The default constructor */ 8*u'D@0
public Page(){ *d C| X
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} o4p5`jOG@
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/** construct the page by everyPage |iUF3s|?
* @param everyPage C&Q[[k"kb
* */ |_p7vl"
public Page(int everyPage){ dY}5Kmt
this.everyPage = everyPage; NOs00 H
} sZ=!*tb-
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/** The whole constructor */ /E<Q_/'Z
public Page(boolean hasPrePage, boolean hasNextPage, m#BXxS#B<_
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int everyPage, int totalPage, {D8opepO)
int currentPage, int beginIndex){ Fy5:|CN
this.hasPrePage = hasPrePage; O<p=&=TD7
this.hasNextPage = hasNextPage; 9`92
>
this.everyPage = everyPage; VvIUAn
this.totalPage = totalPage; $)*qoV
this.currentPage = currentPage; &V+_b$
this.beginIndex = beginIndex; ,$t1LV;o=
} oX^N>w0F
&V
axv$v}
/** r(wf>w3
* @return O\Y*s
* Returns the beginIndex. ,1 H|{ <
*/ /
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publicint getBeginIndex(){ 2|?U%YrHWs
return beginIndex; <=|^\r
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} FP&Ykx~
pFd{Tdh
/** zfDfy!\2_
* @param beginIndex 3>3t(M|
* The beginIndex to set. LChwHkRHJI
*/ T-s[na(/L
publicvoid setBeginIndex(int beginIndex){ j}}as
this.beginIndex = beginIndex; 2xy{g&G
} G!F_Q7|-
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/** Wb^g{F!W
* @return R6GlQ G
* Returns the currentPage. S[/D._5QD%
*/ SrWmV@"y
publicint getCurrentPage(){ HZ{DlH;&
return currentPage; 5C-n"8&C&
} >Zm|R|{BE
vHymSU/J
/** <&1hJ)O
* @param currentPage V22Br#+
* The currentPage to set. f0{tBD!%
*/ up?S (.*B
publicvoid setCurrentPage(int currentPage){ FSZ :}Q
this.currentPage = currentPage; y>J6)F
=
} pug;1UZ
!r*JGv=
/** L_zB/(h
* @return .,p@ee$q
* Returns the everyPage. 'A/{7*,
*/ Co<F<eXe
publicint getEveryPage(){ B]#iZ,Tp
return everyPage; #@M'*X_%}K
} V8%( h[
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AgN@
/** bwjLMWEVq
* @param everyPage t/x]vCP,2D
* The everyPage to set. Zq/=uB7Z
*/ `g}en%5b\
publicvoid setEveryPage(int everyPage){ 2DBFY1[Pk
this.everyPage = everyPage; 5.Nc6$
N
} 8;,(D#p
59_VC('
/** 3=lQZi<]%
* @return cn$0^7?
* Returns the hasNextPage. p!LaR.8]
*/ u&Xn#fh
publicboolean getHasNextPage(){ ^12}#I
return hasNextPage; LtDGu})1
} >$A, B
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/** N?%FVF
* @param hasNextPage kgF x
* The hasNextPage to set. /T<,vR
*/ hQJ-
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publicvoid setHasNextPage(boolean hasNextPage){ 2\xEMec
this.hasNextPage = hasNextPage; l\=He
} KJ6:ZTbW
&K,rNH'R
/** +d8?=LX
* @return JZrZDW>M
* Returns the hasPrePage. B}h8c
*/ J#k.!]r,Y
publicboolean getHasPrePage(){ S\118TpD
return hasPrePage; <:0d%YB)
} lz0'E'%{P
EK^["_*A
/** u6p
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* @param hasPrePage V34]5
* The hasPrePage to set. EDGAaN*Q
*/ v<S?"#
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publicvoid setHasPrePage(boolean hasPrePage){ +JBYGYN&K
this.hasPrePage = hasPrePage; b@N*W]
} @1peJJ{
P/~kX_
/** 8IihG
\
* @return Returns the totalPage. fK9wr@1
*
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*/ D5fhOq+g
publicint getTotalPage(){ i<uk}
return totalPage; P*8DM3':
} )@.6u9 \
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/** ~f!iz~
* @param totalPage \_zp4Xb2
* The totalPage to set. ]g0\3A
*/ 8G
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publicvoid setTotalPage(int totalPage){ JNgl
this.totalPage = totalPage; b+ v!3|
} K.2l)aRd
x4bj?=+
} b!-F!Lq/+0
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ob;$yn7ZO1
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 i\u m;\
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个PageUtil,负责对Page对象进行构造: #i~2C@]
java代码: By-A1|4Cp`
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/*Created on 2005-4-14*/ WAt | J2
package org.flyware.util.page; Y^W.gGM
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import org.apache.commons.logging.Log; i=G.{.
import org.apache.commons.logging.LogFactory; XQ]5W(EP
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/** b!Z-HL6
* @author Joa "Gh?hU,WWZ
* Pq:GvM`
*/ r6*~WM|Sq7
publicclass PageUtil { 4-: TQp(
=5sUpPV(
privatestaticfinal Log logger = LogFactory.getLog !(EJ. |LH
f}1R,N_fC
(PageUtil.class); +u:Q+PkM
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/** 9e|]H+y
* Use the origin page to create a new page ^"!j m
* @param page ]M;aVw<!
* @param totalRecords TZ,kmk#
* @return szy^kj^2
*/ 9"YOj_z
publicstatic Page createPage(Page page, int S%7^7MSqA
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totalRecords){ _g(4-\
return createPage(page.getEveryPage(), &_EjP
hZ
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page.getCurrentPage(), totalRecords); MQv2C@K9F
} iYJzSVO
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/** 62X;gb
* the basic page utils not including exception ag$mc8-p[
6(`Bl$M9
handler ? }2]G'7?
* @param everyPage KF"&9nB
* @param currentPage )NwIEk>Tf
* @param totalRecords ?4U|6|1
* @return page y0R5YCq\":
*/ x]gf3Tc58
publicstatic Page createPage(int everyPage, int *@|EaH/
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currentPage, int totalRecords){ nSL
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everyPage = getEveryPage(everyPage); 'Zdjd]
currentPage = getCurrentPage(currentPage); /OpVr15
int beginIndex = getBeginIndex(everyPage, ;MqH)M
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currentPage); + a%Vp!y
int totalPage = getTotalPage(everyPage, tnbtfG;z#
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totalRecords); _z<y]?q
boolean hasNextPage = hasNextPage(currentPage, z@nJ-*'U8
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totalPage); EPQ~V
boolean hasPrePage = hasPrePage(currentPage); d85\GEF9i
ubn`w=w$
returnnew Page(hasPrePage, hasNextPage, qFo'"z`84
everyPage, totalPage, B*+3A!{s
currentPage, ic}M)S FD;
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beginIndex); Xj/U~
} f&w8o5=|I
O'~c;vBI
privatestaticint getEveryPage(int everyPage){ KKR@u(+"a
return everyPage == 0 ? 10 : everyPage; ,r{[l D^
} gHLBtl/
KWVEAHIn
privatestaticint getCurrentPage(int currentPage){ fI2/v<[
return currentPage == 0 ? 1 : currentPage; 0W|}5(C
} a}Db9 =
etX&o5A
privatestaticint getBeginIndex(int everyPage, int Yq;|Me{h
[TAW68f'
currentPage){ ~RV>V*l
return(currentPage - 1) * everyPage; } PD]e*z{Z
} "p43#
ESk<*-
privatestaticint getTotalPage(int everyPage, int lF]cUp#<
U2*g9Es
totalRecords){ ?*}^xXI/
int totalPage = 0; /P*mF^Y
#"^F:: b-
if(totalRecords % everyPage == 0) VZ?"yUZ Id
totalPage = totalRecords / everyPage; oyGO!j
else 3"O)"/"Q.
totalPage = totalRecords / everyPage + 1 ; CKShz]1
xkIRI1*!
return totalPage; +~O0e-d
} r)P^CZm
&UhI1mi]h
privatestaticboolean hasPrePage(int currentPage){ T~%}(0=m
return currentPage == 1 ? false : true; %RE-_~GF
} ;$|[z<1RdW
(U"Ub;[7
privatestaticboolean hasNextPage(int currentPage, z~TG~_s
bkQEfx.
int totalPage){ s? /#8 `
return currentPage == totalPage || totalPage == 4\)"Ih
LRO'o{4$E
0 ? false : true; G.2ij%Zz
} 9Foo8e
8r^~`rL
=VMV^[&>
}
y{hy
>hcA:\UPk
?Z-(SC
G=lcKtMdg
-!uut7Z|
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ^dB~#A1
OR[6pr@
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 BJI}gm2y
7XKPC+)1ya
做法如下: (pBOv:6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Bl5*sfjG
I@VhxJh
的信息,和一个结果集List: }mRus<Ax
java代码: v?zA86d_
JcsJfTI
)ndcBwQc"
/*Created on 2005-6-13*/ L8K=Q
package com.adt.bo; 4`F(RweGx
fY@Y$S`Fh
import java.util.List; ]M
AB
v. ,|#}0 o
import org.flyware.util.page.Page; T9r"vw
{6%vmMbJ
/** y,&UST
* @author Joa -lHSojq~H
*/ >jEn>H?
publicclass Result { :fI|>I
~
cjzhuH/y
private Page page; zx"'WM*
>$,A [|R
private List content; &V7@ TZ
QjH;'OVt
/** 70NQ9*AAy
* The default constructor %M{qr!?uj
*/ z -|gw.y
public Result(){ pKDP1S#<
super(); 1@Dp<Q
} 3V:{_~~
4 4bTx y
/** jf0D
* The constructor using fields OjxaA[$
* 2XhtK
* @param page sg"J00
* @param content 3-cCdn
*/ }ge~Nu>w
public Result(Page page, List content){ 1qWIku
this.page = page; 0yW#).D^b
this.content = content; ;h[p "
} 8wGq:@#=
,at"Q$)T
/** ,KvF:xqA
* @return Returns the content. $qkVu
*/ 4Q2=\-KFj
publicList getContent(){ D=}UKd
return content; C?@vBM}
} /BB(riG
]v=*WK
/** q$)$?"
* @return Returns the page. >]N}3J}47g
*/ *Ag</g@ h
public Page getPage(){ }{>)2S
return page; O@;;GJ
} <a/TDW
yOKpi&! r
/** shjc`Tqm
* @param content 5\RTy}w3x
* The content to set. L:$kd `v[
*/ KT1/PWa
public void setContent(List content){ oej5bAi
this.content = content; 6"@+Jz
} 0* Ox>O>
EBjSK/
/** MB]8iy8
* @param page @Qw~z0PE<l
* The page to set. ^(<Ecdz(
*/ |l\&4/SJ
publicvoid setPage(Page page){ -#0(Jm'
this.page = page; @c&}\#;
} E6"+\-e
} hLYy
[?rK9I&
GT$.#};u
+"8 [E~Bih
N$1ZA)M
2. 编写业务逻辑接口,并实现它(UserManager, lJaR,,
j`JY3RDD
UserManagerImpl) W;~ f865
java代码: (S1c6~
on?<3eED
2'O2n]{
/*Created on 2005-7-15*/ EfxW^zm)
package com.adt.service; C:S*juK
Ore>j+
import net.sf.hibernate.HibernateException; +ZH-'l
^)$(Fe<
import org.flyware.util.page.Page; 12
y=Eh
FT.6^)-
import com.adt.bo.Result; }DH3_M!
}^|g|xl!
/** uTsxSkHb/
* @author Joa s"u6po.'
*/ [
j'L*j
publicinterface UserManager { HgH\2QL3&
4n55{?Z
public Result listUser(Page page)throws j\W"P_ dpd
e/+_tC$@p@
HibernateException; 3khsGD@
#2*l"3.$.R
} MBy0Ky
ze* =7
\o-9~C\c*
r\#_b4-v3h
ZJL8"(/R
java代码: _v~c3y).
+ucj>g1(#
G- _h 2
/*Created on 2005-7-15*/ #G</RYM~m
package com.adt.service.impl; "*08?KA
%6A."sePO
import java.util.List; <( "M;C3y
nV/8u_
import net.sf.hibernate.HibernateException; N=Q<mj;,
9f UD68Nob
import org.flyware.util.page.Page; b02V#m;Z
import org.flyware.util.page.PageUtil; D~~"wos
I,[njlO:
import com.adt.bo.Result; Jo%`N#jG
import com.adt.dao.UserDAO; g.L~Z1-
import com.adt.exception.ObjectNotFoundException; ^\<nOzU?
import com.adt.service.UserManager; \X3Q,\H
@
tX'`4!{@+
/** a1^CpeG~
* @author Joa h%4aL38
*/ \!O3]k,r
publicclass UserManagerImpl implements UserManager { w&c6iFMd0
xIt' o(jQH
private UserDAO userDAO; Y-Iu&H+\
y]3`U
UvXD
/** |3LD"!rEx
* @param userDAO The userDAO to set. 7rIz
*/ 7j,-o
publicvoid setUserDAO(UserDAO userDAO){ qq
Vjx?bKe
this.userDAO = userDAO; W=E+/ZvPt
} { XI 0KiE
L{pz)')I
/* (non-Javadoc) x*`S>_j27=
* @see com.adt.service.UserManager#listUser }~I(e
|uUGvIsXn
(org.flyware.util.page.Page) #%Hk-a=>)#
*/ =g.R?H8cj5
public Result listUser(Page page)throws o7gYj\
w\V1pu^6@
HibernateException, ObjectNotFoundException { _#\e5bE=Z
int totalRecords = userDAO.getUserCount(); fyt ODsb>
if(totalRecords == 0) n>t&l8g%g
throw new ObjectNotFoundException 7Shau%2C
Dx)>`yJk$;
("userNotExist"); {^J/S}L]
page = PageUtil.createPage(page, totalRecords); V /.Na(C~
List users = userDAO.getUserByPage(page); 1iA0+Ex(j
returnnew Result(page, users); XAb%V'
} )2z<5 `
$Cgl$A
} wDQ@$T^vh
#}PQ !gZ
Q,ezAE
D=+md
nrBpq
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }Z/[ "
uOQ!av2"Rf
询,接下来编写UserDAO的代码: RGu`Jk
3. UserDAO 和 UserDAOImpl: f-.dL
java代码: t]3> X
7$"A2x
ZZs@P#]
/*Created on 2005-7-15*/ us5<18M5
package com.adt.dao; Fe[)-_%G
h6CAd-\x\
import java.util.List; %`EyG
^4 MJ
import org.flyware.util.page.Page; -(dtAo6
Wtwo1pp
import net.sf.hibernate.HibernateException; pD@:]VP
|2Vhj<6
/** ]KQv]'
* @author Joa 9T\uOaC"
*/ m&PB5s\=
publicinterface UserDAO extends BaseDAO {
P,Z
K
%K`th&331
publicList getUserByName(String name)throws bIWSNNV0F
JpRn)e'Z
HibernateException; bcR";cE
adcH3rV
publicint getUserCount()throws HibernateException; A`B>fI
UF&B7r
publicList getUserByPage(Page page)throws 0&~JC>S
6%a9%Is!O
HibernateException; -Qy@-s $
H|Y*TI2vf8
} U#iGR5&^3
&ir|2"HV
+`J~c|(
[+F6C
dEhFuNO<2
java代码: 0$qK: ze
dfA2G<Uc
Bq5-L}z
/*Created on 2005-7-15*/ /n2qW.qJ>
package com.adt.dao.impl; n2(`O^yd7C
aMJW__,
import java.util.List; 1gA^Qv~?
XtZeT~/7RT
import org.flyware.util.page.Page; zv-9z
R?3N><oh*
import net.sf.hibernate.HibernateException; c
W1`[b
import net.sf.hibernate.Query; j].=,M<dxE
S`Xx('!/|
import com.adt.dao.UserDAO; 4wkmgS
mP ]a}[
/** cq`!17"k
* @author Joa uv&4
A,h
*/ h ^.jK2I
public class UserDAOImpl extends BaseDAOHibernateImpl O[|_~v:^
j0b>n#e7
implements UserDAO { kt#t-N;}x
8U%y[2sT
/* (non-Javadoc) N;HG@B!m
* @see com.adt.dao.UserDAO#getUserByName -kP$S qR~
hz+O.k],?
(java.lang.String) rQ-,mq
*/ Rb_%vOM
publicList getUserByName(String name)throws y&W3CW\:
xV0:K=
HibernateException { kz"QS.${
String querySentence = "FROM user in class h+!@`c>)Y
pkE4"M!3=
com.adt.po.User WHERE user.name=:name"; B/_~j_n$m
Query query = getSession().createQuery
9+
A~(
eJ0Xfw%y%T
(querySentence); FfC\uuRe
query.setParameter("name", name); 6zp]SPY
return query.list(); gF2,Jm@"6
} zEKVyZd*{
m++=FsiX=
/* (non-Javadoc) FN<Sagj
* @see com.adt.dao.UserDAO#getUserCount() l`Ae&nc6
*/ 8Sk$o.Gy
publicint getUserCount()throws HibernateException { 8
KRo<
int count = 0; (]nX:t
String querySentence = "SELECT count(*) FROM Hva/C{Y
Ftdx+\O_i&
user in class com.adt.po.User"; %,+&Kl
I
Query query = getSession().createQuery z.~jqxA9
(j-_iOQ]i+
(querySentence); '-BD.^!!
count = ((Integer)query.iterate().next ,YBe|3
'si{6t|
()).intValue(); ,B:r^(}0j
return count; 2BO&OX|X
} vawS5b;
_/J`v`}G
/* (non-Javadoc) 3=("vR`!
* @see com.adt.dao.UserDAO#getUserByPage 'A,)PZL9i
R:`)*=rL%
(org.flyware.util.page.Page) +xuj ]J
*/ A!v:W6yiz
publicList getUserByPage(Page page)throws =u`tlN5pOT
wg4Ol*y'
HibernateException { <
w;490g
String querySentence = "FROM user in class P}"T3u\N
(sSGJS'X
com.adt.po.User"; E5IS<.
Query query = getSession().createQuery 61}eB/;7
tpa<)\7KJ
(querySentence); XG E.*aI
query.setFirstResult(page.getBeginIndex()) F+]cFx,/
.setMaxResults(page.getEveryPage()); X2E=2tXl`7
return query.list(); 3TRG] 5
} &Z(6i}f,Gp
t[/APm-k~>
} :eH\9$F`x;
YH&q5W,KX
!ou;yE&<,
tHEZuoi
I9<%fv
至此,一个完整的分页程序完成。前台的只需要调用 @V Sr'?7-
:_h#A}8Xd
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ek60[a
q<K/q"0-l
的综合体,而传入的参数page对象则可以由前台传入,如果用 k3T374t1b
? U* `!-
webwork,甚至可以直接在配置文件中指定。 !j&#R%D
"TVmxE%(
下面给出一个webwork调用示例: ~
\b~
java代码: # S(b2LEc
7u:QT2=&
_K B%g_{
/*Created on 2005-6-17*/ ;?v&=Z't.
package com.adt.action.user; uQ%3?bx)T
_:%i6c*"
import java.util.List; wlEK"kKU
DUwms"I,%
import org.apache.commons.logging.Log; (o^?i2)g
import org.apache.commons.logging.LogFactory; !gcea?I
import org.flyware.util.page.Page; @SI,V8i
dsg-;*%
import com.adt.bo.Result; /CUBs!
import com.adt.service.UserService; Bh&dV%'
import com.opensymphony.xwork.Action; a+j"8tHu$
O"#/>hmv-
/** kJ?AAPC
* @author Joa #8$"84&N.
*/ O=jzz&E+
publicclass ListUser implementsAction{ 4HpKKhv"
K'y|_XsBB)
privatestaticfinal Log logger = LogFactory.getLog @aP1[( m
:%h|i&B
(ListUser.class); \}!/z]u
aMGyV"6(-6
private UserService userService; F\jawoO9
,20l` :
private Page page; L4ZB0PmN'
}qR6=J+Dx
privateList users; #|T2`uYotf
0lOR.}]q
/* xUTTRJ(\
* (non-Javadoc) cdN =HM~I
* -e>Z!0
* @see com.opensymphony.xwork.Action#execute() D^}2ilk!
*/ <`?%Cz AO
publicString execute()throwsException{ Z@bSkO<Y
Result result = userService.listUser(page); {gxP_>
page = result.getPage(); #N;&^El
users = result.getContent(); h^,av^lg^
return SUCCESS; csA-<}S5]b
} @1 i<=r
Ro;I%j
/** mW~*GD~r
* @return Returns the page. s~ou$!|
*/ nb ?(zDJ8
public Page getPage(){ cI&XsnY
return page; Gzs$0Ki=
} Y[W :Zhl;
Rd<K.7&A}
/** C;%dZ
* @return Returns the users. "y5bODq3t
*/ x[u6_6=q9
publicList getUsers(){ qj4jM7
return users; w"W;PdH)
} x&r f]R
?6HnN0A)
/** IVVX3RI
* @param page #$]8WSl
* The page to set. ou{V/?rb
*/ :,
3S5!(y
publicvoid setPage(Page page){ :^-\KE`3
this.page = page; <\eRa{ef
} `xZ,*G7(*
|9p0"#4u
/** CSz+cS
* @param users :F9Oj1lM%
* The users to set. bkz/V/ Y
*/ *aq"c9
publicvoid setUsers(List users){ y.s\MWvv>u
this.users = users; ] g8z@r"b
} ML0_Uc3en
'ka$@,s :
/** 9Q*:II
* @param userService g1:%986jv
* The userService to set. H7k@Br
*/ 3w"_Onwk
publicvoid setUserService(UserService userService){ \}X[0ct2!
this.userService = userService; >
6=3y4tP
} ^8YBW<9
} |>1#)cONW
Cs\jPh;"
dpX Fx"4A
ru~!;xT
bAy\Sr
#/
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, \cf'Hj}
4eF{Y^
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 +zXcTT[V
9p1@Lfbj
么只需要: >&k`NXS|V
java代码: $=`d[04
- P"
YLS*uXB&.
<?xml version="1.0"?> %$'fq*8b
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork PS=q):R|
rQJ\Y3.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- f0R+Mz8{
r'lANl-v
1.0.dtd"> S<-5<Pg
9}L2$^#,NA
<xwork> 3}fhU{-c
G}LV"0?
<package name="user" extends="webwork- b|;h$otC
NqveL<r`
interceptors"> {wgq>cb
JT~Dr KI_
<!-- The default interceptor stack name jQ7-M4qO/
==oJhB
--> j,lI\vw<
<default-interceptor-ref mx}4iO:Xp
NciIqF
name="myDefaultWebStack"/> Pc7p2
a*:GCGe
<action name="listUser" mNEh\4ai
O%6D2d
class="com.adt.action.user.ListUser"> u } +?'B)
<param FvO,* r9
Oi]B%Uxy=
name="page.everyPage">10</param> Jr= fc*f
<result [LUqF?K&
=BJe}AV
name="success">/user/user_list.jsp</result> bTZ.y.sI
</action> atmW? Z
.:GOKyr(~
</package> #{^qBP[
g#Ta03\
</xwork> yy[ Y=
SLUQFoz}
BjA$^ i|8
SXN]${
@1<VvW=
JG7K-W|!c
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 |[>yJXxEL@
da_0{;wR
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+IRI|d
m(^N8k1K;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Plhakngj
@K}h4Yok
^zS;/%
Bu+?N%CBi
L6;'V5Mg72
我写的一个用于分页的类,用了泛型了,hoho Ta/u&t4
*"4l}&
java代码: pU[yr'D.r
{`T^&bk
,nGQVb
package com.intokr.util; TtKKU4 yp
ez)Ks`
import java.util.List; 5tzO=gO[
<`NsX
6t
/** 5hDy62PRr
* 用于分页的类<br> [N}QCy
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 25j\p{*
* lC,~_Yb
* @version 0.01 !IB}&m
* @author cheng +Z86Qz_
*/ b`,Sd.2=('
public class Paginator<E> { };EB[n
privateint count = 0; // 总记录数 [Fv,`*/sm
privateint p = 1; // 页编号 4\g[&
privateint num = 20; // 每页的记录数 !^v~hD$_q
privateList<E> results = null; // 结果 z|Yt|W
N:S2X+}(
/** $|TLt{ K
* 结果总数 6Z2|j~
*/ 9_e_Ne`i`?
publicint getCount(){ 3(vm'r&5n>
return count; zjSl;ru
} 7zJ2n/`m*
IN;9p w
publicvoid setCount(int count){ `&xdS H
this.count = count; Uj3HAu
} !c-MC|
wzJdS}Yy!y
/** n2Mpo\2
* 本结果所在的页码,从1开始 n:b,zssP
* W:6#0b"_#
* @return Returns the pageNo. 25 :v c0
*/ kC6Y?g
publicint getP(){ 4FZ/~Y1}
return p; H@~tJ\L
} gs0`nysM#
$#3[Z;\
/** Sm?|,C3V
* if(p<=0) p=1 7,V_5M;t
* jp@X,HES
* @param p rc~)%M<[2
*/ ;OD-?bC
publicvoid setP(int p){ H\N}0^ea
if(p <= 0) x K\i&A
p = 1; : yq2
XE%r
this.p = p; 6E:H
} /C5py-I
bn5O2
/** qt/6o|V
* 每页记录数量 PMW@xk^<Y
*/ >K1e=SY
publicint getNum(){ VGu(HB8n#
return num; .;.Zbhm
} 5MZv!N
4xg1[Z%:
/** Bss*-K]
* if(num<1) num=1 }J92TV
*/ `T ^0&#
publicvoid setNum(int num){ 7!FiPH~kM
if(num < 1) TBba3%
num = 1; a2i:fz=[
this.num = num; jsr)
} :`"-Jf
R!WDQGR(2
/** AN[pjC<
* 获得总页数 b9 li
*/ @\xEK5 SG
publicint getPageNum(){ I,,SR"
return(count - 1) / num + 1; aRI. &3-
} 99,=dzm
D!Nc&|X^
/** .h4Z\R`
* 获得本页的开始编号,为 (p-1)*num+1 v)nv"o[
*/ {#`wW`U^
publicint getStart(){ LmJ _$?o
return(p - 1) * num + 1; #UI`+2w
} Yl$@/xAa
l[m*csDk"
/** H1KXAy`&
* @return Returns the results. Zy:q)'D=
*/ K V?+9qa,
publicList<E> getResults(){ @Gw]cm
return results; 6"}F
KRR
} EM+! ph
0b8=94a{>
public void setResults(List<E> results){ yv>uzb`N
this.results = results; i.?rom
} _4#7 ? p
9Av{>W?
public String toString(){ b E40^e
StringBuilder buff = new StringBuilder In!^+j
b].U/=Hs
(); Zp6VH
buff.append("{"); eWD!/yr|
buff.append("count:").append(count); /l3Oi@\
buff.append(",p:").append(p); Gi$\th,
buff.append(",nump:").append(num); KZ^>_K&
buff.append(",results:").append wc"~8Ah
}j2t8B^&:
(results); D;+Y0B
buff.append("}"); {Dy,|}7s
return buff.toString(); Az#kE.8b*A
} -;qK_x
p-rQ'e
} [C~N#S[]
",,.xLI7
Q^l!cL| {