Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 OyIw>Wfv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #'`{Qv0,
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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 vY3h3o
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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 [-w%/D%@
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。 .xkM.g4{~
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分页支持类: c71y'hnT
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java代码: |-H&o]
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package com.javaeye.common.util; Z\sDUJ
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import java.util.List; %yC,^
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publicclass PaginationSupport { |s_GlJV.
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publicfinalstaticint PAGESIZE = 30; 1Y,Z
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privateint pageSize = PAGESIZE; :4|4 =mkr
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privateList items; ~TtiO#,t
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privateint totalCount; /9X7A;O
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privateint[] indexes = newint[0]; 7+*WH|Z@
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privateint startIndex = 0; iy"*5<;*DD
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public PaginationSupport(List items, int O6Y0XL
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totalCount){ :T~ [
setPageSize(PAGESIZE); EQ_aa@M7
setTotalCount(totalCount); h+,@G,|D
setItems(items); gqR(.Pu
setStartIndex(0); Wp,R^d
} F'Z,]b'st3
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public PaginationSupport(List items, int )/P}?`I
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totalCount, int startIndex){ uAk.@nfiEv
setPageSize(PAGESIZE); ?7A>+EY
setTotalCount(totalCount); a q-~B~c`g
setItems(items); GvAb`c=
setStartIndex(startIndex); =~gvZV-<
} a'T;x`b8U,
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public PaginationSupport(List items, int x1a:u
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totalCount, int pageSize, int startIndex){ <3
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setPageSize(pageSize); '%;m?t%q
setTotalCount(totalCount); Dp:BU|r
setItems(items); vQ.R{!",>
setStartIndex(startIndex); EM_d8o)`B
} gM]:Ma
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publicList getItems(){ Gm`8q}<I
return items; .)3 <Q}>
} TqQ[_RKg2
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publicvoid setItems(List items){ Nboaf
this.items = items; OTv)
} \7_y%HR
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publicint getPageSize(){ zm# ?W
return pageSize; iow"n$/
} Ul# r
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publicvoid setPageSize(int pageSize){ 3' 'me
this.pageSize = pageSize; IGgL7^MF
} ,: ^u-b|
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publicint getTotalCount(){ *^r}"in
return totalCount; iDD$pd,e\
} fV~~J2IK
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publicvoid setTotalCount(int totalCount){ #K&Gp-
if(totalCount > 0){ +,l-Nz
this.totalCount = totalCount; 'fW-Y!k%
int count = totalCount / ;@J}}h'y
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pageSize; @+DX.9
if(totalCount % pageSize > 0) fsXy"#mOkD
count++;
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indexes = newint[count]; tBSW|0
for(int i = 0; i < count; i++){ R!1p^~/
indexes = pageSize * {)Xy%QV
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i; 62u4-}JzF
} #z42C?V
}else{ cb bFw
this.totalCount = 0; d5 -qZ{W
} r<\u6jF
} ,z6~?6m
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publicint[] getIndexes(){ qSQ~D(tO
return indexes; 1*7@BP5
} Zd&S@Z
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publicvoid setIndexes(int[] indexes){ HT@=evV
this.indexes = indexes; 4K74=r),i
} ]'S^]
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publicint getStartIndex(){ t,'<gI
return startIndex; JtZ7ti
} =M-p/uB]
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publicvoid setStartIndex(int startIndex){ s^SJY{
if(totalCount <= 0) ]^]wP]R_
this.startIndex = 0; t<qiGDJ<d
elseif(startIndex >= totalCount) nFn5v'g
this.startIndex = indexes N g,j#
}7X%'Bg=M
[indexes.length - 1];
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elseif(startIndex < 0) p[cX O=
this.startIndex = 0; adw2x pj
else{ I:.s_8mH}
this.startIndex = indexes M3AXe]<eC1
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[startIndex / pageSize]; @PU [:;
} PW4q~rc=:
} ntY]SK%Z
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publicint getNextIndex(){ _4f;<FL
int nextIndex = getStartIndex() + W9)&!&<o
v>56~AJ
pageSize; 1eKT^bgM
if(nextIndex >= totalCount) svSVG:48
return getStartIndex(); E'8;10s
else Dzbz)Zst
return nextIndex; &wX]_:?
} cnLro
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publicint getPreviousIndex(){ KTv$
int previousIndex = getStartIndex() - -YE^zzh
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pageSize; y)*RV;^
if(previousIndex < 0) H>C=zo,oiC
return0; -HuA
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else x"~JR\yzKJ
return previousIndex; wS*E(IAl
} Y ay?=Y{
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} A=4OWV?
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抽象业务类 xkn;,`t^lJ
java代码: v2?ZQeHr_(
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/** W4N{S.#!
* Created on 2005-7-12 F5Va+z,jg
*/ j@9T.P1
package com.javaeye.common.business; ;);kEq/=P
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import java.io.Serializable; Y0>y8UV
import java.util.List; BzzTGWq\
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import org.hibernate.Criteria; xfQ1T)F3g
import org.hibernate.HibernateException; [vgtc.V
import org.hibernate.Session; wj+*E6o-n
import org.hibernate.criterion.DetachedCriteria; $^P0F9~0
import org.hibernate.criterion.Projections; ZW}_DT0
import 7L??ae
]-q;4.
org.springframework.orm.hibernate3.HibernateCallback; nR~(0G,H
import nK,w]{<wG!
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org.springframework.orm.hibernate3.support.HibernateDaoS KSvE~h[#+
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upport; o@Oqm> ]SS
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import com.javaeye.common.util.PaginationSupport; OCUr{Nh
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public abstract class AbstractManager extends YMgNzu
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HibernateDaoSupport { weQ_*<5%
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privateboolean cacheQueries = false; yw!{MO
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privateString queryCacheRegion; q@qsp&0/
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publicvoid setCacheQueries(boolean Y}/-C3)
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cacheQueries){ :
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this.cacheQueries = cacheQueries; `g,..Ns-r
} ZEQ Ex]Y
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publicvoid setQueryCacheRegion(String /B3i C#?
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queryCacheRegion){ O}P`P'Y|'
this.queryCacheRegion = *fdTpXa
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queryCacheRegion; Rv=YFo[B
} Vj-h;rB0z
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publicvoid save(finalObject entity){ >V937
getHibernateTemplate().save(entity); %$I;{-LD
} rUl+
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publicvoid persist(finalObject entity){ 9z0p5)]n>
getHibernateTemplate().save(entity); phK/
} S 5U;#H
_&x%^&{
publicvoid update(finalObject entity){ C}X\|J
getHibernateTemplate().update(entity); n?Q|)2 2
} .N3mb6#[R
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publicvoid delete(finalObject entity){ SKtr tm
getHibernateTemplate().delete(entity); -} +[
} ~dSr5LUD
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publicObject load(finalClass entity, s.#`&Sd>
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finalSerializable id){ l.]xB,k
return getHibernateTemplate().load h 0|s
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(entity, id); >usL*b0%
} *I+Q~4
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publicObject get(finalClass entity, ,I9bNO,%JK
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finalSerializable id){ >eaaaq9B-
return getHibernateTemplate().get No$3"4wk
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(entity, id); HsWk*L `y
} QWU[@2@%r
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publicList findAll(finalClass entity){ D=$)n_F
return getHibernateTemplate().find("from #z(]xI)"
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" + entity.getName()); Q/?$x*\>
} [K Qi.u
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publicList findByNamedQuery(finalString $xqa{L%B
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namedQuery){ #G3<7PK
return getHibernateTemplate |:o4w
ni<(K
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().findByNamedQuery(namedQuery); %xW"!WbJ|
} YR70BOxK
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publicList findByNamedQuery(finalString query, 6b,V;#Anj
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finalObject parameter){ NlqImM=r,
return getHibernateTemplate >~f]_puT
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().findByNamedQuery(query, parameter); N mG#
} QPx^_jA
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publicList findByNamedQuery(finalString query, N+|d3X!
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finalObject[] parameters){ 0J|3kY-n>
return getHibernateTemplate h1RSVp+?n
"4Nt\WQ
().findByNamedQuery(query, parameters); XZf$K _F&M
} jdN`mosJ
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publicList find(finalString query){ RCrCs
return getHibernateTemplate().find ;a/E42eN;
:0/7, i
(query); TC('H[
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} #mT"gs
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publicList find(finalString query, finalObject sKWfXCd
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parameter){ "Q<MS'a
return getHibernateTemplate().find VTM/hJmwJ
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(query, parameter); =|=(l)8
} &m3lXl
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public PaginationSupport findPageByCriteria dr(*T
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(final DetachedCriteria detachedCriteria){ "%_+-C<L4
return findPageByCriteria ]'cs.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +vH4MwG$.&
} J,hCvm
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public PaginationSupport findPageByCriteria PCvWS.{
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(final DetachedCriteria detachedCriteria, finalint <%d>v-=B
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startIndex){ }C:r9?T
return findPageByCriteria \zY!qpX<
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(detachedCriteria, PaginationSupport.PAGESIZE, ~&T~1xsFJ
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startIndex); LLo;\WGZ
} dG{A~Z z
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public PaginationSupport findPageByCriteria 0@(&eH=
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(final DetachedCriteria detachedCriteria, finalint ;jXgAAz7
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pageSize, vdZW%-A&\
finalint startIndex){ d$RIS+V
return(PaginationSupport) ]lbuy7xj63
}6#
getHibernateTemplate().execute(new HibernateCallback(){ 1^}+=~
publicObject doInHibernate g(052]
f 2.HF@
(Session session)throws HibernateException { q'DW~!>qX
Criteria criteria = ^#$n~]s
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detachedCriteria.getExecutableCriteria(session); bsX[UF
int totalCount = 53D]3
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((Integer) criteria.setProjection(Projections.rowCount d~H`CrQE*
?}0 ,o.
()).uniqueResult()).intValue(); *g%yRU{N
criteria.setProjection %A`+WYeuX
t!XwW$@
(null); vt8By@]:
List items = n[z+<VGwC
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criteria.setFirstResult(startIndex).setMaxResults +2{Lh7Ks
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(pageSize).list(); khe}*y
PaginationSupport ps = u[YGm:}
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new PaginationSupport(items, totalCount, pageSize,
)2.Si#
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startIndex); e=
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return ps; yAt^;
} +whDU2 "
}, true); q1,~
} fu5=k:/c
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public List findAllByCriteria(final KPF1cJ2N
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DetachedCriteria detachedCriteria){ \dVOwr
return(List) getHibernateTemplate v+XJ*N[W
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().execute(new HibernateCallback(){ vzM^$V
publicObject doInHibernate .]^?<bG
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(Session session)throws HibernateException { G[=c
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Criteria criteria = pP_LR
ks}
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detachedCriteria.getExecutableCriteria(session); t_^4`dW`
return criteria.list(); C]6O!Pb0
} ~}P,.QQ
}, true); &ncvGDGi
} ]G\}k
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public int getCountByCriteria(final s AkdMo
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DetachedCriteria detachedCriteria){ rp$'L7lrX
Integer count = (Integer) V`- 9m$
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getHibernateTemplate().execute(new HibernateCallback(){ >7|VR:U?B
publicObject doInHibernate Ac@VGT:9
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(Session session)throws HibernateException { uT"rq:N
Criteria criteria = G\i9:7 `
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detachedCriteria.getExecutableCriteria(session); OXA7w.^
return *wearCPeJ
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criteria.setProjection(Projections.rowCount h{Y",7]!
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()).uniqueResult(); gdc<ZYcM
} Xvu(vA
}, true); tw;}jh
return count.intValue(); 1Mzmg[L8
} 1M 6D3d_
} as|<}:V
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用户在web层构造查询条件detachedCriteria,和可选的 la!~\wpa
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 T)/eeZ$
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PaginationSupport的实例ps。 P:c w|Q
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ps.getItems()得到已分页好的结果集 54T`OE
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ps.getIndexes()得到分页索引的数组 /m1\ iM\
ps.getTotalCount()得到总结果数 zX[U~.
ps.getStartIndex()当前分页索引 ';CNGv -
ps.getNextIndex()下一页索引 0mE 0 j
ps.getPreviousIndex()上一页索引 Ud?Q%)X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (.:e,l{U%
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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 l?e.9o2-
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一下代码重构了。 r!v\"6:OM
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我把原本我的做法也提供出来供大家讨论吧: 4hB]vY\T
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首先,为了实现分页查询,我封装了一个Page类: wk^B"+Uhy
java代码: IGl9g_18
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/*Created on 2005-4-14*/ BmT! aue
package org.flyware.util.page; i!Ba]n
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/** _BufO7`.
* @author Joa K(4_a``05
* 5BIY<B+i
*/ U^PgG|0N
publicclass Page { dtDFoETz
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/** imply if the page has previous page */ '1[Ft03
privateboolean hasPrePage; cAw/I@jG
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/** imply if the page has next page */ 4W75T2q#
privateboolean hasNextPage; 2?C)&
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/** the number of every page */ /vt3>d%B;
privateint everyPage; :gv"M8AP
F59 TZI
/** the total page number */ W9&=xs6
privateint totalPage; }e1ZbmW
&]Tmxh(
/** the number of current page */ l1I#QB@5n
privateint currentPage; WJi]t9 3
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/** the begin index of the records by the current 4g/dP^
mpyt5#f
query */ y_)FA"IkE
privateint beginIndex; Ry&6p>-
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e-;}366}
/** The default constructor */ R2NZ{"h
public Page(){ 6Wn1{v0
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} ;uW FHc5@B
ib m4fa
/** construct the page by everyPage }p
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* @param everyPage /r 5eWR1G
* */ y =@N|f!
public Page(int everyPage){ 4H/OBR
this.everyPage = everyPage; SbZ6t$"
} st*gs-8jJ;
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/** The whole constructor */ Ri'n
public Page(boolean hasPrePage, boolean hasNextPage, +ZYn? #IQ
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int everyPage, int totalPage, NK+o1
int currentPage, int beginIndex){ KvSG;
this.hasPrePage = hasPrePage; \vNU,WO
this.hasNextPage = hasNextPage; buC{r,
this.everyPage = everyPage; $b\P|#A
this.totalPage = totalPage; x-c"%Z|
this.currentPage = currentPage; bt *k.=p
this.beginIndex = beginIndex; d9ihhqq3}
} A&{Nh` q
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/** pAEx#ck
* @return ~[: 2I
* Returns the beginIndex. *Ex|9FCt$
*/ 1YA% -~
publicint getBeginIndex(){ ;S{(]K7i
return beginIndex; Ac6=(B
} %y@AA>x!
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/** 'qi}|I
* @param beginIndex P>L +t`'
* The beginIndex to set. <3iMRe
*/ 0(Ij%Wi,
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; J,G
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} )0MB9RMk1
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/** }G=M2V<L
* @return X]=t>
* Returns the currentPage. $e\M_hp*J
*/ `/g
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publicint getCurrentPage(){ [lAp62i5
return currentPage; wr4:Go`
} NI5``BwpO
n%-0V>
/** E]6
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* @param currentPage Bx!-"e
* The currentPage to set. _@g;8CA
*/ tkhCw/
publicvoid setCurrentPage(int currentPage){ YqG7h,F
this.currentPage = currentPage; ]4{H+rw
} -M2yw
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/** iE{&*.q_}>
* @return _ |p8M!
* Returns the everyPage. j|n R"!
*/
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publicint getEveryPage(){ 598i^z{~0%
return everyPage; Al'3?
} ZuIefMiG~+
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/** tgaO!{9I?
* @param everyPage u>$t'
* The everyPage to set. X8|EHb<
*/
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publicvoid setEveryPage(int everyPage){ `6YN3XS
this.everyPage = everyPage; K^$=dLp
} ':W[ A
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/** ] - .aL
* @return -N@|QK>
* Returns the hasNextPage. y]imZ4{/
*/ N7_"H>O$0U
publicboolean getHasNextPage(){ >+waX"e
return hasNextPage; r/sNrB1U"y
} X.V~SeS
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/** |3%8&@ho
* @param hasNextPage C>~TI,5a3
* The hasNextPage to set. Tr|JYLwF
*/ .o8t+X'G
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; S$k&vc(0
} ]d`VT)~vje
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/** B:QHwzd
* @return i&k7-<
* Returns the hasPrePage. L(o15
*/ yBRC*0+Vy
publicboolean getHasPrePage(){ 7rPF$ \#
return hasPrePage; iOdpM{~*
} 5?L<N:;J_
>{Tm##@,k
/** Z=
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* @param hasPrePage [r-p]"R
* The hasPrePage to set. aoTP[Bp
*/ hEk$d.!}
publicvoid setHasPrePage(boolean hasPrePage){ ZN6Z~SL_i~
this.hasPrePage = hasPrePage; "mNq&$
} ^t"'rD-I
FN;^"H
/** {e5= &A
* @return Returns the totalPage. ZB&6<uw
* ETLD$=iS
*/ L+QLLcS~EM
publicint getTotalPage(){ Fx+*S3==%e
return totalPage; Ev P{p
} i?~3*#IpD
!Uc T RI
/** y?:.;%!E
* @param totalPage xm@_IL&P
* The totalPage to set. qFNes)_r
*/ 2
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publicvoid setTotalPage(int totalPage){ @I*{f
this.totalPage = totalPage; |CzSU1ma
} frQ{iUx
;GI&lpKK
} bTu9;(
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 '=6\v!
"Pf~iwfw
个PageUtil,负责对Page对象进行构造: e]tDy0@
java代码: {V-v-f
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/*Created on 2005-4-14*/ m9A!D
package org.flyware.util.page; z~Q>V]a>;
/SrAW`;"
import org.apache.commons.logging.Log; N"1B/u
import org.apache.commons.logging.LogFactory; d:{O\
7`YEH2
/** (b6NX~G-:
* @author Joa l0hlM#
* /OJ`c`>Q:
*/ BX^tR1
publicclass PageUtil { ;Q&5,<
N)j
;ZG\p TCA
privatestaticfinal Log logger = LogFactory.getLog nJLFfXWx
gGS=cdlV
(PageUtil.class); S@ f9c
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/** gl_^V&c
* Use the origin page to create a new page -B\HI*u
* @param page c7E11 \%&Z
* @param totalRecords 7`hP?a=
* @return XF_pN[}
*/ ',4iFuY
publicstatic Page createPage(Page page, int T${Q.zHY[!
N{~YJ$!8
totalRecords){ ]]juN
return createPage(page.getEveryPage(), ED&
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9
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page.getCurrentPage(), totalRecords); f0aKlhEC
} gOOPe5+ J
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/** .@Dxp]/B}
* the basic page utils not including exception 0k(a VkZ I
{&T_sw@[
handler ^Js9 s8?$
* @param everyPage b,%C{mC
* @param currentPage +XYE {E5
* @param totalRecords ")HFYqP>9
* @return page 9pxc~=
*/ x~j`@k,;
publicstatic Page createPage(int everyPage, int oFGhNk
;l-!)0U
currentPage, int totalRecords){ &q|K!5[k
everyPage = getEveryPage(everyPage); }XM(:|8J,
currentPage = getCurrentPage(currentPage); x7x\Y(@
int beginIndex = getBeginIndex(everyPage, `%Al>u5
Q'mM3pq4r
currentPage); kd$D 3S^{
int totalPage = getTotalPage(everyPage, az|N-?u
5j-YM
totalRecords); ;?g6QIN9
boolean hasNextPage = hasNextPage(currentPage, ^Zy%fv,
y
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totalPage); M_w<m
boolean hasPrePage = hasPrePage(currentPage); `P;s8~
7;(UF=4
returnnew Page(hasPrePage, hasNextPage, ^UhBH@ti
everyPage, totalPage, JO"<{ngsQ
currentPage, DXK}-4"\
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beginIndex); Z@@K[$
} fn6J*[`
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privatestaticint getEveryPage(int everyPage){ Z} r*K%
return everyPage == 0 ? 10 : everyPage; =+MPFhvg!
} .JiziFJ@mj
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privatestaticint getCurrentPage(int currentPage){ x`IEU*z#
return currentPage == 0 ? 1 : currentPage; ([LSsZ]sj
} 4u47D$=
["e3Ez
privatestaticint getBeginIndex(int everyPage, int 5=?\1`e1[
o"BoZsMk
currentPage){ WYYa/,{9.
return(currentPage - 1) * everyPage; "E?2xf|.
} Hi`//y*92H
@)&=%
privatestaticint getTotalPage(int everyPage, int n%s]30Xs
PJrtMAcKq
totalRecords){ xDoC(
int totalPage = 0; JOLaP@IPT
cFnDmtI:
if(totalRecords % everyPage == 0) l.bYE/F0&
totalPage = totalRecords / everyPage; pWsDzb6?%
else Gvqxi|
totalPage = totalRecords / everyPage + 1 ; T+K):ug
P{+T<bk|
return totalPage; 8j\cL'
} \:ak ''
r|PB*`
privatestaticboolean hasPrePage(int currentPage){ |:<f-j7t~
return currentPage == 1 ? false : true; zEy N)
} 8j %Tf;
o/Q;f@
privatestaticboolean hasNextPage(int currentPage, !pdb'*,n
O[)kboY
int totalPage){ 5m(^W[u `
return currentPage == totalPage || totalPage == Q &K
rOOT8nkR#
0 ? false : true; b4ONh%
} A_5P/ARmI
0h\smqm
|3[Wa^U5
} ndz]cx
vucxt }Ti
g:dH~>
2!J&+r
K;z7/[%
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Uu(SR/R}
}m;,Q9:+m^
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 o-OHjFfB
iv;Is[<o
做法如下: M`i\VG
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {I #]@,
\EtQ5T*u
的信息,和一个结果集List: a^zibPG
java代码: nd1+"-,q
h*$y[}hDuv
g^{@'}$
/*Created on 2005-6-13*/ m(#LhlX
package com.adt.bo; ?fjuh}Q5h
#[~pD:qqM
import java.util.List; Zk"eA'"\
/}
WDU
import org.flyware.util.page.Page; 7 Vo$(kj
kB|B
/** $m1z-i;/
* @author Joa =mpVYA
*/ v`zJb00DT
publicclass Result { gSUcx9f]
9:1Q1,-i!-
private Page page; hB>oJC
"4+WZR]
private List content; 0rDh}<upjk
i/ )am9
/** Tewb?:
* The default constructor @jSYB+D
*/ sVv xHkt@
public Result(){ a\E:sPM'>
super(); |>27B
} Z}l3l`h!
~r`9+b[9{
/** iS Gq!D
* The constructor using fields SB|Qa}62
* '~&X wZ&
* @param page D
(mj7oB
* @param content ;y\IqiA{o
*/ (Dl$k Gn
public Result(Page page, List content){ W$OG(m!W>
this.page = page; cKim-
this.content = content; K3;nY}\>
} sOJQ,"sB
\$\ENQ;Nk
/** "*5hiTr8+
* @return Returns the content. dA0.v+Foz"
*/ @EpIh&
publicList getContent(){ X+S9{X#Cm
return content; O_DtvjI'
} C/kW0V7
"C19b:4H
/** |J}Mgb-4
* @return Returns the page.
L0@SCt
*/ uv(Sdiir8
public Page getPage(){ -Sx\Xi"<o=
return page; 7~aM=8r
} I@%t.%O Jp
#Xb+`'
/** &<J[Q%2
* @param content WIf0z#JMJm
* The content to set. %_L\z*+
*/ 5>j)kx=J9
public void setContent(List content){ i9A+gtd
this.content = content; [[Fx[
} pDcjwlA%
/[)qEl2]K
/** 5sJJGv#6
* @param page H_ox_
u}
* The page to set. i2(1ki/|O
*/ s,n0jix@
publicvoid setPage(Page page){ ^!z[t\$
this.page = page; <$~mE9a6
} %S nd\
} lM{
+!-G,
NchXt6$i9
(B_\TdQ
"xHg qgFyO
OJzs Q
2. 编写业务逻辑接口,并实现它(UserManager, D-(w_$#
3G~@H>j
UserManagerImpl) Z1Z1@2 T
java代码: (%xwl
>W`4aA
oifv+oY
/*Created on 2005-7-15*/ kO{s^_qR^c
package com.adt.service; /)(#{i*
;Tc`}2
import net.sf.hibernate.HibernateException; xs:n\N
;R?I4}O#R8
import org.flyware.util.page.Page; %V{7DA&C
uYil ?H{kH
import com.adt.bo.Result; 2e9es
fKeT~z{~
/** q**G(}K
* @author Joa 5qoSEI-m
*/ ANSFdc
publicinterface UserManager { KiOcu=F
;Uu(zhbj
public Result listUser(Page page)throws 6 9NQ]{1
$K'|0
HibernateException; EEZw_ 1
MR<;i2p
} C[Dav&=^F
aj,T)oDbt6
I=9!Rs(QF
z`FCs,?K
B0WJ/)rK<
java代码: ez!C?
8o0%@5M
'n$%Ls}S
/*Created on 2005-7-15*/ ql?=(b;D
package com.adt.service.impl; hk;7:G
(BfgwC)
import java.util.List; Zg`Mz
_?
S"k*6U
import net.sf.hibernate.HibernateException; 'hv k
qt^T6+faaQ
import org.flyware.util.page.Page; ZMLg;-T.&4
import org.flyware.util.page.PageUtil; 5-0{+R5v
jSuL5|Gui
import com.adt.bo.Result; cEd+MCN
import com.adt.dao.UserDAO; mL`5 uf
import com.adt.exception.ObjectNotFoundException; Eb>78k(3I)
import com.adt.service.UserManager; (S`2[.j
mzc
4/<th
/** S (N\cw$
* @author Joa r~n sN*t
*/ VZ](uF BY
publicclass UserManagerImpl implements UserManager { 1`9xIm*9w
@%lBrM
private UserDAO userDAO; zyg
}F
e^Ky<*Y
/** &o97u4xi
* @param userDAO The userDAO to set. ,qrQ"r9
*/ 4bJZmUb
publicvoid setUserDAO(UserDAO userDAO){ ]B]*/
this.userDAO = userDAO; ;6{@^
} N**g]T
0`
ee#):
-p
/* (non-Javadoc) 4T<Lgb
* @see com.adt.service.UserManager#listUser )){9&5,0:
IMl!,(6;
(org.flyware.util.page.Page) ^~HQC*
*/ [j:[
public Result listUser(Page page)throws F0UVo
13&0rLS
HibernateException, ObjectNotFoundException { .eO?Z^
int totalRecords = userDAO.getUserCount(); g}U3y'
if(totalRecords == 0) la?Wnw
throw new ObjectNotFoundException t/PlcV_M"
$4T2z-
("userNotExist"); |xvy')(b
page = PageUtil.createPage(page, totalRecords); 0%
#<c p
List users = userDAO.getUserByPage(page); <ExZ:ip
returnnew Result(page, users); tpTAeQ*:d
} I]y.8~xs
%9#gB
} 1#4PG'H
cl*PFQp9j
@M8|(N%
~|AwN [
r]Ff{la5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @hImk`&[N
#vqo -y7@
询,接下来编写UserDAO的代码: KyO8A2'U
3. UserDAO 和 UserDAOImpl: $VQtwuYt
java代码: =FT98H2*|
z]bwnJfd
{gaai
/*Created on 2005-7-15*/ ?[MsQQd~
package com.adt.dao; tDCw-
KB!|B.ChN(
import java.util.List; ;eZ#b jw-d
$eBX
import org.flyware.util.page.Page; `O8b1-1q~
OLj\-w^
import net.sf.hibernate.HibernateException; nPgeLG"00
W Qc>
/** ?P7]u>H
* @author Joa <(e8sNe
*/ |J~eLh[d
publicinterface UserDAO extends BaseDAO { hwDbs[:
X5*C+ I=2
publicList getUserByName(String name)throws ow' lRHZ
(?b@b[D~4
HibernateException; 9r2IuS0
$.489x+'Z
publicint getUserCount()throws HibernateException; 5Y3i|cj
X}6#II
publicList getUserByPage(Page page)throws *$M'`vj:
V8~jf-\$b
HibernateException; Sj(F3wY
STA4 p6
} ='E$-_
=)OC|?9C\
=[<m[.)i
g+C!kaC)
S?0)1O
java代码: NS,5/t
Z2bcCIq4
i$KpDXP\
/*Created on 2005-7-15*/ ]fI/(e_U
package com.adt.dao.impl; 4E:bp
W];EKj,3W
import java.util.List; &wetzC)
BD#.-xWV
import org.flyware.util.page.Page; e[t<<u3"
41 vL"P
K
import net.sf.hibernate.HibernateException; i
NWC6y
import net.sf.hibernate.Query; -NBiW6b~
m!OMrZ%)}
import com.adt.dao.UserDAO; \BI/G
|k{-l!HI
/** U~2`P
* @author Joa oT|m1aGE
*/ ,`8Y8
public class UserDAOImpl extends BaseDAOHibernateImpl '7im
dy>|cj
implements UserDAO { - n6jG}01b
RX2{g^V7
/* (non-Javadoc) s-VSH
* @see com.adt.dao.UserDAO#getUserByName fH8!YQG8$
&VWlt2-R0h
(java.lang.String) Cv=GZGn-
*/ g9my=gY
publicList getUserByName(String name)throws 4rU!4l
G7* h{nE
HibernateException { cUDg M
String querySentence = "FROM user in class !@
YXZ
nD,{3B#
com.adt.po.User WHERE user.name=:name"; ;</Twm;:
Query query = getSession().createQuery wX'}4Z=C~
$rG<uO
(querySentence); a1MFjmq
query.setParameter("name", name); 2#_38=K=@
return query.list(); 5`E))?*"Pe
} \T-~JQVj
`HX3|w6W;
/* (non-Javadoc) [D'Gr*5~{
* @see com.adt.dao.UserDAO#getUserCount() 3LlU]
*/ px9>:t[P
publicint getUserCount()throws HibernateException { 2go>
int count = 0; f e
$Wu
String querySentence = "SELECT count(*) FROM o VB"f
b5e@oIK
user in class com.adt.po.User"; uiBTnG"
Query query = getSession().createQuery M'1HA
:nQp.N*p
(querySentence); RFG$X-.e
count = ((Integer)query.iterate().next i|\{\d
a]VGUW-
()).intValue(); $<ddy/4
return count; GF--riyfB
} amB@N6*
\}inT_{g
/* (non-Javadoc) Y~"9L|`f/
* @see com.adt.dao.UserDAO#getUserByPage wTpD1"_R
r7)@M%A
(org.flyware.util.page.Page) @%@zH%b
*/ FUaNiAr[
publicList getUserByPage(Page page)throws _JOP[KHb
)45_]tk>
HibernateException { 4-:7.I(hq
String querySentence = "FROM user in class =p\Xy*
,sb1"^Wc
com.adt.po.User"; ~|)
9RUXr>
Query query = getSession().createQuery 4S *,\ q]q
!z=pP$81
(querySentence); &
QY#3yj=
query.setFirstResult(page.getBeginIndex()) ]R Mb,hJ
.setMaxResults(page.getEveryPage()); H,>#|F
return query.list(); 'H=weH
} Gm&2R4 )EP
U4_"aT>My
} gGKKs&n7
: z~!p~
w4:<fnOM
@
u1Q-:
J#7(]!;F
至此,一个完整的分页程序完成。前台的只需要调用 R[yL_>
z
Z%/W)t
userManager.listUser(page)即可得到一个Page对象和结果集对象 )bYez
H%Y%fQ~^
的综合体,而传入的参数page对象则可以由前台传入,如果用 dB`b9)Tk0z
YMAQ+A!
webwork,甚至可以直接在配置文件中指定。 ^"tqdeCb=
I>((o`
下面给出一个webwork调用示例: g[!Cj,
java代码:
gNa#|
hh&Js'd
&N{zkMf
/*Created on 2005-6-17*/ %\yK5V5
package com.adt.action.user; 0QR.
%}F"*.
import java.util.List; zPQ$\$7xB
om7`w
]
import org.apache.commons.logging.Log; D9ywg/Q91
import org.apache.commons.logging.LogFactory; bhKV +oN
import org.flyware.util.page.Page; slSR=XOG
zH+<bEo=1=
import com.adt.bo.Result; P|N?OocE
import com.adt.service.UserService; tQ0=p|
T]
import com.opensymphony.xwork.Action; ]hUKuef
?-{IsF^
/** )[DpK=[N^p
* @author Joa ;xW{Ehq-h
*/ eG^z*`**
publicclass ListUser implementsAction{ /'Bdq?!B&
/\~W$.c
privatestaticfinal Log logger = LogFactory.getLog M,L@k
3*\8p6G
(ListUser.class); i;HH !
TaN
V~c(]K)-
private UserService userService; 0|Q.U
.jum "va%
private Page page; -4`sqv ]
QX/]gX
privateList users; #wD7 \X-f
di<B ~:l58
/* sWW\bK0B4
* (non-Javadoc) y7;
5xF?q
* Heohe|an
* @see com.opensymphony.xwork.Action#execute() t;XS;b%
*/ g)N54WV
publicString execute()throwsException{ (lb`#TTGx
Result result = userService.listUser(page); &U0WkW
page = result.getPage();
/Ef4EX0
users = result.getContent(); |QqWVelc
return SUCCESS; q @*UUj@
} eHROBxH&
WnO DDr
/** +cw{aI`a8
* @return Returns the page. U;>B7X;`E4
*/ >";%2u1
public Page getPage(){ YRu%j4Tx
return page; ^~*8 @v""
} FP@A;/c
UR\ZN@O
/** =jBL'|k5
* @return Returns the users. 8ipW3~-4
*/ %8g$T6E[<2
publicList getUsers(){ 0c-QIr}m
return users; 2:n|x5\H
} ,FS?"Ni
T*p|'Q`
/** _dY:)%[]
* @param page ],$6&Cm
* The page to set. =QTmK/(|B
*/ v6KL93
publicvoid setPage(Page page){ C,R,:zR
this.page = page; 4Z],+?.[
} #VQ36pCd
% M+s{ l
/** /;b.-v&
* @param users I@+lFG
* The users to set. vFR
1UPF
*/ 7!mJhgGc
publicvoid setUsers(List users){ 9c:5t'Qt5.
this.users = users; Age-AJ
} - =yTAx
wiKCr/
/** .M}06,-
* @param userService _82<|NN:
* The userService to set. D@2Ya/c
*/ ^CO#QnB @
publicvoid setUserService(UserService userService){ kaV%0Of]
this.userService = userService; }t}38%1i
} MyK^i2eD
} -Zttj /K
G|<] Ma9x
b,zR5R^D;
;;D%
l^m+
|c]> Q
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 2c!h2$w
Z<w,UvJa
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
>_n:_
4b]IazL)
么只需要: 9F/|`
java代码: gjO
*h3`
wYC9~ms-
g2!0vB>
<?xml version="1.0"?> u_h=nk
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork e1:u1(".
a"MTQFm'
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
Cl%V^xTb
"<7$2!
1.0.dtd"> `>dIF.
b;SFI^
<xwork> YL;SxLY
,ZLG7e
<package name="user" extends="webwork- /IrKpmbq
L;L2j&i%v)
interceptors"> U$MWsDn
?<-wHj)
<!-- The default interceptor stack name Y=PzN3
oM/B.U2a
--> L;
@aE[#z
<default-interceptor-ref _a?wf!4>P
Q1]V|S;)X
name="myDefaultWebStack"/> ]Fb8.q5(Y
s$IcDuBu
<action name="listUser" 8/Lu'rI
ajf_)G5X P
class="com.adt.action.user.ListUser"> [^cs~
n4
<param ")fOup@ ^a
Ky=(urAd
name="page.everyPage">10</param> pb,{$A
<result 4Sd+"3M
1Kp?bwh"u
name="success">/user/user_list.jsp</result> 0V{>)w!Fo
</action> $%lHj+(
>\N$>"~a
</package> wY."Lw> 6
Ubn
</xwork> @G^j8Nl+J}
H@VBP
Q}Q
Y j,9V],
&Z;Eu'ia
5%vP~vy_}
sE(X:[Am
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 .D>A'r8U
D'U\]'.
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。 +H5 jRw
F#zQQ)(Pf
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 i4 y(H
m-Mhf;
PX+"" #
p\4h$."
Br_3qJNVP
我写的一个用于分页的类,用了泛型了,hoho 2b{@]Fp
ylo]`Nq
java代码: TXY
AX!Md:s
/3xFd)|Ds
package com.intokr.util; 7$E2/@f
%3#b6m~
import java.util.List; CNpCe-%&
EbHUGCMO
/** 7`j|tb-
* 用于分页的类<br> O&gy(
* 可以用于传递查询的结果也可以用于传送查询的参数<br> P,s)2 s'nZ
* #t5JUi%in*
* @version 0.01 >d1aE)?
* @author cheng {|t?
*/ |\yDgs%EGy
public class Paginator<E> { 7z0;FW3>9
privateint count = 0; // 总记录数 v=8~ZDY
privateint p = 1; // 页编号 x<)!$cg
privateint num = 20; // 每页的记录数 ?CL z@u~
privateList<E> results = null; // 结果 _&8KB1~
)^QG-IM
/** F~11 _
* 结果总数 {d{WMq$
*/ kC,DW%Ls
publicint getCount(){ j$JV(fz
return count; G5X|JTzpu<
} g/J^K*3]
<3J=;.\6
publicvoid setCount(int count){ d-_93
this.count = count; kG~ivB}x
} "X!_37kQ
Jf8'N
ot
/** &El[
* 本结果所在的页码,从1开始 g
tSHy*3]
* g]TI8&tP!L
* @return Returns the pageNo. PdE)m/
*/ dzk?Zg
publicint getP(){ >u%[J!Y;;
return p; eN7yjd'Y6
} PT=2LZ
QjT#GvHY
/** Xl
'\krz
* if(p<=0) p=1 iI/'!85
* r.W"@vc>
* @param p 1&x0+~G
*/ %'p|JS
publicvoid setP(int p){ Sd/d [
if(p <= 0) LqH?3):
p = 1; &nY2u-Q
this.p = p; :5qqu{GL
}
e>s.mH6A
^AC+nko*
/** lj% ;d'
* 每页记录数量 [s&
y_[S
*/ \ &|w;
publicint getNum(){ vb4G_X0S
return num; u6CMRZ$
} 22H=!.DJ
S7\jR%pb
/** M4$4D?
* if(num<1) num=1 Zzzi\5&gU
*/ iJ~iJ'vf
publicvoid setNum(int num){ |cBF-KNZ
if(num < 1) w{UKoU
num = 1; u9[w~U#
this.num = num; |Z +E(F
} \H'CFAuF
~wQ WWRk
/** =,1zl}PR
* 获得总页数 }j5@\c48
*/ I(r5\A=
publicint getPageNum(){ ~(L<uFU V
return(count - 1) / num + 1; ZYp-dlEXq
} :/?R9JVI
{ /Q?
/** ob()+p.k K
* 获得本页的开始编号,为 (p-1)*num+1 *1 eTf
*/ '3kL=(
publicint getStart(){ aABE= 9Y
return(p - 1) * num + 1; we@En
.>f
} $f@-3/V6{
?&t|?@
/** M<me\s)
* @return Returns the results. 0.,&B5)
*/ 41_sSqq;^
publicList<E> getResults(){ Tx&qp#FS
return results; #._6lESK
} ]k%KTvX*G
pJ@DHj2@
public void setResults(List<E> results){ >ww1:Sn
this.results = results; R^w >aZoJ
} ?VHwYD.B
5v03<m0`y
public String toString(){ p9bxhnn|
StringBuilder buff = new StringBuilder B7^n30+L
h4xf%vA(;
(); jMN@x]6w
buff.append("{"); ^bgm0,M
buff.append("count:").append(count); ROiX=i
buff.append(",p:").append(p); 0}3'h#33=
buff.append(",nump:").append(num); hdWp
buff.append(",results:").append '%/u103{e
*/m~m?
(results); 3lEU$)QA3
buff.append("}"); k*+ZLrT
return buff.toString(); oXOO 10
} d}G."wnG9,
6je%LHhL
} s)ajy^6'M
1$!K2=%OXj
@9Pn(fd]