Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 GzJ("RE0)v
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 qqm7p
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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 Cst:5m0!
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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 pa7Iz^i
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分页支持类: 6[-N})
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java代码: ews4qP
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package com.javaeye.common.util; 4FmT.P
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import java.util.List; U!GG8;4
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publicclass PaginationSupport { e}Y|'bG
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publicfinalstaticint PAGESIZE = 30; <i~MBy.
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privateint pageSize = PAGESIZE; ebbC`eFD
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privateList items; rt\i@}
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privateint totalCount; gAy,uP~,
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privateint[] indexes = newint[0]; $6BD6\@
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privateint startIndex = 0; H_RVGAbU
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public PaginationSupport(List items, int IF<?TYy=3B
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totalCount){ {Z>OAR#
setPageSize(PAGESIZE); X 8TwMt
setTotalCount(totalCount); Iz'*^{Ssm
setItems(items); O-rHfIxY
setStartIndex(0); +doZnU,
} -}l iG
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public PaginationSupport(List items, int PD@]2lY(
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totalCount, int startIndex){ (T1)7%Xs
setPageSize(PAGESIZE); '\I.P
setTotalCount(totalCount); p'lL2n$E
setItems(items); !,rp|
setStartIndex(startIndex); gZ!vRO<%
} wnaT~r@U'
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public PaginationSupport(List items, int "3kIQsD|j
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totalCount, int pageSize, int startIndex){ Mlr\#BO"9
setPageSize(pageSize); B~/:["zTh&
setTotalCount(totalCount); @M[t|
setItems(items); }Y/uU"t
setStartIndex(startIndex); Ap&Bwo 8b
} dgLE/r?
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publicList getItems(){ d ] J5c
return items; y{>d&M|
} C;#-2^h
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publicvoid setItems(List items){ _7j-y 9V
this.items = items; d!+8
} [P5+}@t
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publicint getPageSize(){ 9,7IsT8
return pageSize; ;^waUJ\Z
} 9oOr-9t3
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publicvoid setPageSize(int pageSize){ J{W<6AK\S
this.pageSize = pageSize; f(Vr &X
} U)Cv_qe
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publicint getTotalCount(){ hn:
return totalCount; -O.q$D=as
} |7$Fr[2d
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publicvoid setTotalCount(int totalCount){ '&?OhSeN
if(totalCount > 0){ D%L}vugxK
this.totalCount = totalCount; ZPrL)']
int count = totalCount / ~ YQC!x
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pageSize; 7 &y'\
if(totalCount % pageSize > 0) D6cqON0a.
count++; 3lw
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indexes = newint[count]; (;RmfE'PX
for(int i = 0; i < count; i++){ \-XQo
indexes = pageSize * 1SddZ5
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i; ^gP pmb<x
} ,BGaJ|k
}else{ :#CQQ*@
this.totalCount = 0; wc&%icF*cr
} &L&6y()G
} W4
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publicint[] getIndexes(){ H/qv%!/o
return indexes; Ne{2fV>8Ay
} [PVem
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publicvoid setIndexes(int[] indexes){ `a$-"tW~j
this.indexes = indexes; drr
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} JQ-O=8]
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publicint getStartIndex(){ .UxbwTup
return startIndex;
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} u\LbPk
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publicvoid setStartIndex(int startIndex){ G/l 28yt
if(totalCount <= 0) N~c Y ~a
this.startIndex = 0; 2~yYwX
elseif(startIndex >= totalCount) ^[]q/v'3m!
this.startIndex = indexes CC?L~/gPN
)Sz2D[@n
[indexes.length - 1]; ${(c`X
elseif(startIndex < 0) k!9LJ%Xh
this.startIndex = 0; AoL2Wrk]\B
else{ P0R8
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this.startIndex = indexes t0$}
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[startIndex / pageSize]; ,;RAPT4
} s8i@HO
} SSoD}N
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publicint getNextIndex(){ Y9YE:s
int nextIndex = getStartIndex() + nT(Lh/
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pageSize; eouxNw}F1
if(nextIndex >= totalCount) WA~PE` U
return getStartIndex(); PubO|Mf
else lCyBdY9n
return nextIndex; hUL5V1-j
} ]3u$%vc
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publicint getPreviousIndex(){ L[Z
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int previousIndex = getStartIndex() - y `)oD0)Fj
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pageSize; W3AtO
if(previousIndex < 0) UbWeE,T~S
return0; bSK> p3
else %Z:07|57I[
return previousIndex; S,Y\ox-
} `5J`<BPs
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} itH`
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抽象业务类 hv]}b'M$
java代码: orT%lHwjL
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/** nnw5
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* Created on 2005-7-12 pn5A6
#
*/ Mg7nv\6
package com.javaeye.common.business; F.N4Q'2Z
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import java.io.Serializable; 8y9`xRy
import java.util.List; Cob<N'.
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import org.hibernate.Criteria; e!eUgD
import org.hibernate.HibernateException; d]fo>[%Xr
import org.hibernate.Session; ")gd)_FOS
import org.hibernate.criterion.DetachedCriteria; GjHV|)^
import org.hibernate.criterion.Projections; Qp]-:b
import .}xF2'~E/
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org.springframework.orm.hibernate3.HibernateCallback; oU\Q|mN(
import y2_^lW%
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org.springframework.orm.hibernate3.support.HibernateDaoS ,_G((oS40
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upport; f@G3,u!]i
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import com.javaeye.common.util.PaginationSupport; :J
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public abstract class AbstractManager extends Kuj*U'ed7t
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HibernateDaoSupport { E/<5JhI9~
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privateboolean cacheQueries = false; TB oN8cB}
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privateString queryCacheRegion; 2D?V0>/
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publicvoid setCacheQueries(boolean QqF&lMH
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cacheQueries){ &5x
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this.cacheQueries = cacheQueries; -pF3q2zb
} $ts%SDM
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publicvoid setQueryCacheRegion(String K6 {0`'x
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queryCacheRegion){ \G+uK:PC,
this.queryCacheRegion = +nLsiC{&
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queryCacheRegion; Vm3e6Y,K
} AV t(e6H
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publicvoid save(finalObject entity){ \[!k`6#t7
getHibernateTemplate().save(entity); <`rl[C{
} r )pg9}+
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publicvoid persist(finalObject entity){ N:_U2[V^d
getHibernateTemplate().save(entity); MDyPwv\
} 4mqA*c%6S
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publicvoid update(finalObject entity){ o<J_?7c~}
getHibernateTemplate().update(entity); |=xK-;qs
} g_T[m*
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publicvoid delete(finalObject entity){ t%B ,ATW
getHibernateTemplate().delete(entity); )q+Qtz6D
} qjtrU#n
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publicObject load(finalClass entity, h_SDW %($
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finalSerializable id){ 6)@Y 41H]C
return getHibernateTemplate().load &+K:pU?[$
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(entity, id); |q(
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} [r)Hm/_=|U
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publicObject get(finalClass entity, oD@~wcMIT0
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finalSerializable id){ xDJs0P4
return getHibernateTemplate().get SF7p/gG
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(entity, id); :X66[V&eH
} u4W2{
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publicList findAll(finalClass entity){ ~boTh
return getHibernateTemplate().find("from aYmC LLj
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" + entity.getName()); `Dn"<-9:
} O%Mi`\W@
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publicList findByNamedQuery(finalString 7I_1Lnnf
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namedQuery){ Bq20U:f
return getHibernateTemplate A-8[8J
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().findByNamedQuery(namedQuery); )w8h2=l
} NU*6MT4
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publicList findByNamedQuery(finalString query, "%aJ'l2
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finalObject parameter){ 3|Q:tt'|#
return getHibernateTemplate "8Ud&o
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().findByNamedQuery(query, parameter); Y5~_y?BX
} nlsQf3
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publicList findByNamedQuery(finalString query, ]@W.5!5H
Uk u~"OGC
finalObject[] parameters){ @<ba+z>"~4
return getHibernateTemplate P9/5M4]tt
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().findByNamedQuery(query, parameters); v1yNVs\}
} IYq)p
/
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publicList find(finalString query){ .0:twj
return getHibernateTemplate().find [s-Km/
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(query); yWa-iHWC
} y!SElKj
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publicList find(finalString query, finalObject 'aQ"&GX@
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parameter){ I3QK~ V*j)
return getHibernateTemplate().find yz}Agc4.I
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(query, parameter); W6t"n_%?"
} >!|Hns
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public PaginationSupport findPageByCriteria 0/d+26lR
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(final DetachedCriteria detachedCriteria){ <wge_3W#
return findPageByCriteria ~3Y)o|D3
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); gG0P &9xz
} Kc+;"4/#q
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public PaginationSupport findPageByCriteria j4L )D
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(final DetachedCriteria detachedCriteria, finalint "VxZnT
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startIndex){ @Iz vObK
return findPageByCriteria TC1#2nE&T
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(detachedCriteria, PaginationSupport.PAGESIZE, ;7"}I
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startIndex); *ktM<N58
} OPR+K ?
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public PaginationSupport findPageByCriteria r>1M&Y=<
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(final DetachedCriteria detachedCriteria, finalint Y,OSQBgk
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pageSize, 6LRI~*F=3
finalint startIndex){ m!3L/UZ
return(PaginationSupport) V3fd]rIP
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getHibernateTemplate().execute(new HibernateCallback(){ h
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publicObject doInHibernate <JE-#i
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(Session session)throws HibernateException { jW5n^Y)
Criteria criteria = "$KU+?
8;YeEW5
detachedCriteria.getExecutableCriteria(session); )&}\2NK6L
int totalCount = {yQeLION
%"~\Pu*>
((Integer) criteria.setProjection(Projections.rowCount N!>Gg|@~
nj99!"_
()).uniqueResult()).intValue(); @O#4duM4Qz
criteria.setProjection CZ*c["x2
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(null); h%
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List items = ;hi+.ng_
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criteria.setFirstResult(startIndex).setMaxResults hc}dS$=C
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(pageSize).list(); 7q*L-Xe]k
PaginationSupport ps = f>i6f@
(SV(L~T_
new PaginationSupport(items, totalCount, pageSize,
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(.a:jL$
startIndex); xg~q'>
return ps; _ETG.SYq
} +v:t
}, true); .8hB <G
} 8jW{0&ox)
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public List findAllByCriteria(final `T2RaWR4=
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DetachedCriteria detachedCriteria){ %m]9";
return(List) getHibernateTemplate } 5i0R
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@?
().execute(new HibernateCallback(){ 6>ZUx}vYj
publicObject doInHibernate <d~P;R(@
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(Session session)throws HibernateException { +HNY!fv9
Criteria criteria = `2\vDy1,j
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detachedCriteria.getExecutableCriteria(session); ''S*B|:
return criteria.list(); ?1JVzZ4H
} ;Pik},
}, true); l-4T Tg
} PVvNu5k
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public int getCountByCriteria(final bFk >IifN
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DetachedCriteria detachedCriteria){ `#B|l+baq
Integer count = (Integer) $},Y)"mI
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getHibernateTemplate().execute(new HibernateCallback(){ ~TwjcI*/
publicObject doInHibernate tjc3;9
/gT$ d2{
(Session session)throws HibernateException { hXdc5 ?i?
Criteria criteria = _#xS1sD
@Y+YN;57
detachedCriteria.getExecutableCriteria(session); p@] \ N
return v
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criteria.setProjection(Projections.rowCount \G}EI|Wo
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()).uniqueResult(); d{2+>
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} 1P(rgn:8e
}, true); rLO1Sv
return count.intValue(); IFNs)*
} T6MlKcw,t
} @s RRcP~
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用户在web层构造查询条件detachedCriteria,和可选的 |f1 S&b.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 lR[[]Yn
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PaginationSupport的实例ps。 KB49~7XjQ@
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ps.getItems()得到已分页好的结果集 f<WP<!N%
ps.getIndexes()得到分页索引的数组 aP^,@RrL
ps.getTotalCount()得到总结果数 j*@^O`^v
ps.getStartIndex()当前分页索引 -L@4da[]i
ps.getNextIndex()下一页索引 Xdj` $/RI
ps.getPreviousIndex()上一页索引 >2tQ')%DJ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <?'d\B
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 `%}SK~<R
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一下代码重构了。 ;Z|X` <6g
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我把原本我的做法也提供出来供大家讨论吧: mne4u W
-
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首先,为了实现分页查询,我封装了一个Page类: (c;F%m|
java代码: -Yx'qz@
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/*Created on 2005-4-14*/ 1'DD9d{qN
package org.flyware.util.page; _7es_w}R
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/** |PR8P!'
* @author Joa l"^'uGB'
* Oz(0$c
*/ 1y@d`k`t:
publicclass Page { pEgQ)
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/** imply if the page has previous page */ Z .6M~
privateboolean hasPrePage; !$N^Ak5#
{`,dWjy{%
/** imply if the page has next page */ _/Ky;p.
privateboolean hasNextPage; Xkcy~e
+bpUb0.W
/** the number of every page */ D/QSC]"
privateint everyPage; >d-By
("0 7t/||
/** the total page number */ R6l`IlG`
privateint totalPage; A;ip
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/** the number of current page */ B1)gudP`
privateint currentPage; {3n|=
JDPn
/** the begin index of the records by the current {a aI<u
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query */ }jHS
privateint beginIndex; A|>~/OW=@
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/** The default constructor */ lz2B,#
public Page(){ 3z7SK Gy
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} Tbf't^Ot$
MLwh&I9)
/** construct the page by everyPage i) v
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* @param everyPage <q@/Yy32
* */ @@~OA>^
public Page(int everyPage){ j}9][Fm1*
this.everyPage = everyPage; )e&U'Fx
} n;&08M5an}
EB R,j_
/** The whole constructor */ ]}7FTMGbY
public Page(boolean hasPrePage, boolean hasNextPage, ipzv]c&
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int everyPage, int totalPage, kaM=Fk=t
int currentPage, int beginIndex){ zq]I"0Bi.
this.hasPrePage = hasPrePage; 2I'gT$h
this.hasNextPage = hasNextPage; S -$ L2N
this.everyPage = everyPage; $ 9bIUJ
this.totalPage = totalPage; %oPW`r
this.currentPage = currentPage; >YG1sMV-J
this.beginIndex = beginIndex; ;75m 9yGo
} %siBCjvo=
ay~c@RXW
/** 9N1Uv,OtB
* @return {A!1s;
* Returns the beginIndex. ^h wF=
*/ 9! 'qLO
publicint getBeginIndex(){ f</'=k
return beginIndex; SURbH;[
} 9*s''=
u|]{|Ya'%
/** 6/{V#.(
* @param beginIndex E"i<fr
T
* The beginIndex to set. %L;z ~C
*/ ',Y`XP"Q
publicvoid setBeginIndex(int beginIndex){ l Tpn/
this.beginIndex = beginIndex; O3ij/8f
} ivTx6-]
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/** K]c|v
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* @return scr`] tD
* Returns the currentPage. pO]{Y?X:
*/ %3p~5jhm1
publicint getCurrentPage(){ }
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return currentPage; nV`n=x
} DX3xWdnr
Xn:5pd;?B6
/** Q\H1=8
* @param currentPage '7BJ.
* The currentPage to set. >~%!#,C(|U
*/ $MW-c*5a
publicvoid setCurrentPage(int currentPage){ =Sjr*)<@j
this.currentPage = currentPage; 87&BF)]
} YdgDMd-1
NT(gXEZ
/** r.-U=ql
* @return YoC{ t&rY
* Returns the everyPage. Cn\5Vyrl
*/ h>0R!Rl8
publicint getEveryPage(){ r0MUv}p#|L
return everyPage; =yT3#A~<G
} R1,.H92
k&JB,d-mJ%
/** *\gS 2[S
* @param everyPage \/qo2'V
j`
* The everyPage to set. s,z$Vt"h*K
*/ ^)i5.o\
publicvoid setEveryPage(int everyPage){ K!AW8FnHkZ
this.everyPage = everyPage; n,,hE_
} #.Q3}[M
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/** a"ct"g=
* @return /-C`*P=:u
* Returns the hasNextPage. (w1M\yodV
*/ .~3s~y*s
publicboolean getHasNextPage(){ ,Z3 (`ftC
return hasNextPage; B7'rbc'
} f{i~hVF
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/** `Zdeq.R]
* @param hasNextPage adCTo
* The hasNextPage to set. GbFtX\s+5j
*/ ]t2zwHo#
publicvoid setHasNextPage(boolean hasNextPage){ OEZ`5"j
this.hasNextPage = hasNextPage; +ConK>;
} &XvSAw+D@
@%FLT6MY
/** Q4;%[7LU
* @return T
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* Returns the hasPrePage. OV~]-5gau
*/ tVUC@M>'
publicboolean getHasPrePage(){ iY~.U`b`
return hasPrePage; NA :_yA"
} /m"#uC!\
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/** yuef84~
* @param hasPrePage E%.w6-
* The hasPrePage to set. i(Xz3L#(
*/ L- '{
publicvoid setHasPrePage(boolean hasPrePage){ sY-
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this.hasPrePage = hasPrePage; R5"5Z?'
} a+-X\qN
!^Ly#$-X
/** 6@rebe!&=
* @return Returns the totalPage. YK{E=<:
* "VIoVu
*/ KfPYH\0
publicint getTotalPage(){ `F(ghC
return totalPage; tz^2?wO
} q
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/** %&Fsk]T%:
* @param totalPage z+5ZUS2~&
* The totalPage to set. `)aIFAW
*/ On`T
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publicvoid setTotalPage(int totalPage){ dvc=<!"'S
this.totalPage = totalPage; #9/^)^k
} 7]8nW!h;
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} ZFxa2J~ ;
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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 ,N1I\f
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个PageUtil,负责对Page对象进行构造: 2{Johqf
java代码: *x<3=9V
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/*Created on 2005-4-14*/ *.,G;EC^
package org.flyware.util.page; pYBY"r
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import org.apache.commons.logging.Log; $sxm MP
import org.apache.commons.logging.LogFactory; [Yyb)Qf
vVyX[ZZ
/** p"dK,A5#)
* @author Joa AZ7m=Q97
* ~u.((GM
*/ +7V4mF!u
publicclass PageUtil { }o:sU^Pwa
}\?]uNH
privatestaticfinal Log logger = LogFactory.getLog f\vy5''
/\wm/Yx?S
(PageUtil.class); 'V`Hp$r
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/** v1`*}.#
* Use the origin page to create a new page +t
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* @param page /@O$jlX5I
* @param totalRecords -tH ^Deo
* @return JBK(Nk
*/ C[JGt9{Y
publicstatic Page createPage(Page page, int }~O`(mnD}K
\:5M0
totalRecords){ =U`9_]~1c@
return createPage(page.getEveryPage(), O/ih9,
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page.getCurrentPage(), totalRecords); YVW`|'7)|
} y?-zQs0
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/** W }
* the basic page utils not including exception -L6V)aK&
Q13>z%Rge
handler ^V?W'~
* @param everyPage 0K:3?Ik
* @param currentPage JU`5K}H<
* @param totalRecords \\(3gB.Gd
* @return page L3J .Oh
*/ _0Z8V[
publicstatic Page createPage(int everyPage, int nsjrzO79L8
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currentPage, int totalRecords){ A>B_~=
everyPage = getEveryPage(everyPage); \1f&D!F]b
currentPage = getCurrentPage(currentPage); mGC! 7^_D`
int beginIndex = getBeginIndex(everyPage, ZD#{h J-
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currentPage); 3q)y;T\yW
int totalPage = getTotalPage(everyPage, g+pj1ycw/
;NPbEPL[5
totalRecords); \ sc's7
boolean hasNextPage = hasNextPage(currentPage, >mCS`D8
egn9O
totalPage); iZ;y(
boolean hasPrePage = hasPrePage(currentPage); m[$pj~<\
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returnnew Page(hasPrePage, hasNextPage, "8*5!anu-
everyPage, totalPage, j= vlsW
currentPage, `&/~%>
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beginIndex); *Hed^[sO
} ( SiwO.TZ
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privatestaticint getEveryPage(int everyPage){ i"GCm`
return everyPage == 0 ? 10 : everyPage; 9*CJWS;
} p;P
cD
BW{&A&j
privatestaticint getCurrentPage(int currentPage){ Uy;e5<<
return currentPage == 0 ? 1 : currentPage; U%4s@{7
} ATkx_1]KM-
-;RW)n^n
privatestaticint getBeginIndex(int everyPage, int }WM!e"
"]kq,j^]
currentPage){ $guaUe[x
return(currentPage - 1) * everyPage; yN:U"]glC
} 4&}dA^F
ZB'ms[
privatestaticint getTotalPage(int everyPage, int LG:Mksd8=4
MzpDvnI9
totalRecords){ 2&KM&NX~
int totalPage = 0; 2E_d$nsJ
~`!{5:v
if(totalRecords % everyPage == 0) }:xj%?ki
totalPage = totalRecords / everyPage; x2$Y"b?vz
else MgrJ ;?L
totalPage = totalRecords / everyPage + 1 ; ODyKS;
t<H@c9{;*
return totalPage; DEN (pA\
} ^hyp}WN
.:A&5Y-
privatestaticboolean hasPrePage(int currentPage){
v7#`b}'W
return currentPage == 1 ? false : true; @z<IsAE
} c?7Wjy
OqlP_^Zz7p
privatestaticboolean hasNextPage(int currentPage, BQF7S<O+
"iPX>{'En
int totalPage){ mY0FewwTy
return currentPage == totalPage || totalPage == *]+5T-R% $
rpMjDjW
0 ? false : true; /~}<[6ZGCY
} mj|TWDcj+
>O/1Lpl.3
%P HYJc
} %?i~`0-:n%
BU=;rz!;
ZO\x|E!b
~ "stI
]Z=O+7(r
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。 ! ~3zp L
"S^""5
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 g$9EI\a
%Z!3[.%F
做法如下: Vm]u-R`{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "D[/o8Hk
/A"UV\H`f
的信息,和一个结果集List: bd[%=5
java代码: uj^l&"
df@G+v0_1
atYe$Db
/*Created on 2005-6-13*/ m=Fk
package com.adt.bo; 'l&bg 8K9
/;9iDjG
import java.util.List; h-6zQs
]^BgSC
import org.flyware.util.page.Page; ~xakz BE
~%Xs"R1c,
/** D!5{CQl
* @author Joa C)qy=lx%
*/ q&d5V~q
publicclass Result { NjP7?nXSx
CCp&+LRvR
private Page page; ; wKsi_``@
_}3NLAqg
private List content; 3JXKpk?
Kp?j\67S
/** G*'1[Bu
* The default constructor ["ML&2|o
*/ 9ELRn@5.
public Result(){ Io\tZXB
super(); -H9WwFk
} B0dv_'L}L
X(dHhO
/** 6
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* The constructor using fields 1/ <Z6 ?U
* 6hAMk<kx?i
* @param page P?$Iht.^
* @param content EU4j'1!&g<
*/ .g52p+Z#
public Result(Page page, List content){ ]JvZ{fA%*
this.page = page; r0j+P%
this.content = content; ' T%70)CM~
} Ot([5/K
$ i;_yTht
/** x
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* @return Returns the content. )Oix$B!-
*/ D9;s%
publicList getContent(){ E)]RQ~jY?
return content; >@uF ye$
} B0$.oavC
k.Q4oyei
/** 6y
* @return Returns the page. a
n,$Z,G#K
*/ _&}z+(Ug
public Page getPage(){ <nbc
RO.
return page; d6+{^v$#
} 5~\GAjf
%W,V~kb
/** {bMOT*X=A
* @param content :,1kSM%r
* The content to set. dO|n[/qL0
*/ |nT+W|0U
public void setContent(List content){ #1<Jwt+
this.content = content; IfzZ\x
.
} -cs$E2
-
D,&o=EU
/** 8s)(e9Sr
* @param page t>%+[7?6
* The page to set. qJYEsI2M
*/ 66Bx,]"6
publicvoid setPage(Page page){ h7cE"m
this.page = page; 2R>!Wj'G+o
} @@} ]qT*
} f&88N<)
@r9[&
GRj#1OqL
6<m9guv
08F~6e6a8
2. 编写业务逻辑接口,并实现它(UserManager, I6RF;m:Jw
tde&w=ec
UserManagerImpl) F%`O$uXA
java代码: TDZ p1zpXb
DA9f\q
/{FSG!
/*Created on 2005-7-15*/ 35Cm>X
package com.adt.service; Be~In~~
[['
(,,r
import net.sf.hibernate.HibernateException; rkWiGiisM
:3.!?mOe2
import org.flyware.util.page.Page; 8 GW0w
#55_hY#
import com.adt.bo.Result; hL}AgY@
z\+Ug9Of
/** (;cvLop
* @author Joa @JU
Xp
*/ prO ~g
publicinterface UserManager { IUSV\X9
j+NsNIJq
public Result listUser(Page page)throws -mqL[ h,
W~d^ *LZt
HibernateException; U}^`R,C
`*w!S8} m;
} 7 p[NuU*Gg
(%SKTM
%%qg<iO_
{I]>!V0j!
Gc2:^FVlh
java代码: uow{a*qd6
|ohCA&k%;
`=19iAp.
/*Created on 2005-7-15*/ zr^"zcfz&
package com.adt.service.impl; <P0&!yN
?eOw8Rom
import java.util.List; Fb<fQIa
gRg8D{
import net.sf.hibernate.HibernateException; Q1[EiM3
=H/ 5
import org.flyware.util.page.Page; @Jc^ur
import org.flyware.util.page.PageUtil; -v{LT=,O
=.2)wA"e'
import com.adt.bo.Result; NQIbav^5
import com.adt.dao.UserDAO; y!/:1BHlm
import com.adt.exception.ObjectNotFoundException; yyc4'j+
import com.adt.service.UserManager; oN&U@N/>aU
L)9uBdF
/** ((T6z$:hA
* @author Joa *Z2#U?_
*/ +XpQ9Cd
publicclass UserManagerImpl implements UserManager { !MEA@^$#
cg_j.=M-
private UserDAO userDAO; m
e2$ R>@
CMC9%uq
/** $mcq/W
* @param userDAO The userDAO to set. 3h**y
%^
*/ KhZ\q|5
publicvoid setUserDAO(UserDAO userDAO){ YWhp 4`m
this.userDAO = userDAO; 'Oa(]Br[
} I;+>@Cn(g<
*s$:"g-
/* (non-Javadoc) ?9ScKN
* @see com.adt.service.UserManager#listUser +
;_0:+//
}E#1Z\)
(org.flyware.util.page.Page) g^[BnP)I
*/ 3.w &e0Es
public Result listUser(Page page)throws 67]!xy
a}V<CBi
HibernateException, ObjectNotFoundException { x/uC)xm
int totalRecords = userDAO.getUserCount(); O]80";Uv
if(totalRecords == 0) $aDkZj
throw new ObjectNotFoundException sDP8!
} bm ^`QY
("userNotExist"); .wf$]oQQ
page = PageUtil.createPage(page, totalRecords); =&#t("
List users = userDAO.getUserByPage(page); 5q
_n69b
returnnew Result(page, users); rFhi:uRV
} Cp^`-=r+
m(CAXq-t
} W3w$nV
1)J'
pDa
rnRWL4
y;=/S?L.:
"GB493=v
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 l^R1XBP
Mu/hTTiNx
询,接下来编写UserDAO的代码: ].
0;;v6)
3. UserDAO 和 UserDAOImpl: hFMT@Gy
java代码: J
Mm'JK?
Ah_0o_Di
C~R,,
/*Created on 2005-7-15*/ x\5v^$
package com.adt.dao; %s ">:
:|\)=4
import java.util.List; +l;A L5h
s_cur-
import org.flyware.util.page.Page; KEo?Cy?%ff
<uvA([r=Vq
import net.sf.hibernate.HibernateException; mOntc6&]
Lrq e:\
/** RKb (
* @author Joa XvI Y=~
*/ Zb$P`~(%
publicinterface UserDAO extends BaseDAO { ?JMy
%a|m[6+O
publicList getUserByName(String name)throws i Ie{L-Na
"z4V@gk
HibernateException; 'wVi>{?
t)hi j&wzu
publicint getUserCount()throws HibernateException; wVkRrFJ
Le*gdoW .
publicList getUserByPage(Page page)throws |'](zEwq
`Hd~H
HibernateException; $fG~;`T
4nKlW_{,
} WB3YN+Xl3
Lc_cB`
);d"gv(]D
4rUOk"li
,P^4??' o
java代码: r>g5_"FL
U
U@
b)7v-1N
/*Created on 2005-7-15*/ yny1i9
y
package com.adt.dao.impl; {9-n3j}
0X}0,
import java.util.List; sF~!qag4q'
BVu{To:g
import org.flyware.util.page.Page; `&i\q=u+
b{}ao
import net.sf.hibernate.HibernateException; uA~?z:~=
import net.sf.hibernate.Query; =h|xlT
jbp?6GW
import com.adt.dao.UserDAO; nJY3 1(p
l`."rei%)
/** bp>M&1^KY
* @author Joa d0;<Cw~Tl
*/ B!((N{4H+
public class UserDAOImpl extends BaseDAOHibernateImpl "mc ]^O
Or:P*l
implements UserDAO { mq+<2 S
]MnQ3bWq"j
/* (non-Javadoc) =)nJ'}x
* @see com.adt.dao.UserDAO#getUserByName .qs5xGg#9
$^`@ lyr
(java.lang.String) P.-
`[
*/ (: @7IWZf@
publicList getUserByName(String name)throws w+iIay
^y[- e9O|
HibernateException { <aQ5chf7
String querySentence = "FROM user in class I-m Bj8^;
_2w8S\
com.adt.po.User WHERE user.name=:name"; 3f(tb%pa5
Query query = getSession().createQuery N)4R.}
l<:\w.Gl
(querySentence); m(IyW734I
query.setParameter("name", name); f0
kz:sZ9
return query.list(); $ EexNz
} C/MQY:X4
^/~C\
(
/* (non-Javadoc) ;),vUu,k
* @see com.adt.dao.UserDAO#getUserCount() GQDW}b8
*/ A+hA'0isF@
publicint getUserCount()throws HibernateException { aUq2$lw1
int count = 0; Dq+S'x~>
String querySentence = "SELECT count(*) FROM Rw)=<XV)6
( e4#9
user in class com.adt.po.User"; Y|E rVf4
Query query = getSession().createQuery wY"BPl]b
Y6m:d&p=}
(querySentence); /xCX. C
count = ((Integer)query.iterate().next P DwBSj
jmF)iDvjuZ
()).intValue(); 2^y*O
return count; yiMqe^zy
} PQP|V>g
KpT=twcK
/* (non-Javadoc) rp=Y }
* @see com.adt.dao.UserDAO#getUserByPage w%- S5#
,,]<f*N
(org.flyware.util.page.Page) wK0],,RN,h
*/ ~>XqR/v
publicList getUserByPage(Page page)throws NRazI_Z
(Ta (Y=!uq
HibernateException { Wpc8T="q
String querySentence = "FROM user in class %:Z_~7ZR
yw >Frb5p
com.adt.po.User"; =3dd1n;8>
Query query = getSession().createQuery wH+|
&C
1vdG\$
(querySentence); LIn2&r:U
query.setFirstResult(page.getBeginIndex()) A45!hhf
.setMaxResults(page.getEveryPage()); k|^`0~E
return query.list(); 5]K2to)>`
} B7PdavO#
US\h,J\Ju
} K94bM5O 1
1p8hn!V
T\"-q4+=C
WZ=$c]gG
._q<~_~R
至此,一个完整的分页程序完成。前台的只需要调用 rTqGtmulG
z
fu)X!t^
userManager.listUser(page)即可得到一个Page对象和结果集对象 U:bnX51D4
)FN$Jlo
的综合体,而传入的参数page对象则可以由前台传入,如果用 E6zPN?\ <
F>eo.|'
webwork,甚至可以直接在配置文件中指定。 gv1y%(`|n(
FM7`q7d
下面给出一个webwork调用示例: /!fJ`pu!
java代码: zbj V>5
nH B
?}#Iu-IA
/*Created on 2005-6-17*/ g} pD%
package com.adt.action.user; %e:[[yq)G
0~ o,^AW
import java.util.List; e m
}b]eiPWN
import org.apache.commons.logging.Log; T3@34}*
import org.apache.commons.logging.LogFactory; hD{
`j
import org.flyware.util.page.Page; Nh\o39=
f{2I2kJr
import com.adt.bo.Result; J?Oeuk~[D
import com.adt.service.UserService; :*s@L2D6
import com.opensymphony.xwork.Action; D 9UM8Hxi
k 7:Z\RGy
/** U+zntB
* @author Joa V[n,fEPBr
*/ ja6V*CWb
publicclass ListUser implementsAction{ D@kf^1G
;=WwJ Np~
privatestaticfinal Log logger = LogFactory.getLog '4CD
}
KDb`g}1Q
(ListUser.class); 0{
3-'3w ,
private UserService userService; Jhfw$ DF
E6z&pM8<8
private Page page; .y lvJ$
)S;3WnQ)
privateList users; txE+A/>i9
:(@P
*"j
/* )_Z^oH ]<
* (non-Javadoc) ,T$ GOjt
* 3R-5&!i
* @see com.opensymphony.xwork.Action#execute() M6GiohI_"P
*/ }Rw6+;
publicString execute()throwsException{ X4{<{D`0t8
Result result = userService.listUser(page); S&QXf<v
page = result.getPage(); BWNI|pq)v
users = result.getContent(); SM8_C!h:
return SUCCESS; >P]gjYN
} xsiJI1/68
Z{gm4YV
/** ;#9ioGx
* @return Returns the page. %>5>wP
*/ _?bO
/y_y
public Page getPage(){ Ubgn^+AI
return page; 7D1$cmtH
} 3_`)QYU'
\0vs93>?
/** |* ^LsuFb
* @return Returns the users. H \'1.8g/
*/ ZCViZWo
publicList getUsers(){ 64]8ykRD-
return users; DEbMb6)U
} jOzi89
^bP`Iv
/** y#th&YC_b
* @param page 1z4_QZZ.NG
* The page to set. -y{(h%6
*/ pb)kN%
publicvoid setPage(Page page){ gS8+S\2
this.page = page; *,IK4F6>:
} - Ry+WS=
EB*C;ms
/** &AWrM{e
* @param users *")*w> R
* The users to set. A=IpP}7J
*/ esj6=Gh
publicvoid setUsers(List users){ 2pU'&8
this.users = users; DR,7rT{$
} '#h ORQB
5-y*]:g(
/** Q J-|zS.W
* @param userService U^7bj
* The userService to set. 4 Yv:\c
*/ VBw5[
publicvoid setUserService(UserService userService){ 0{vH .b
@
this.userService = userService; GC' e
} ir"t@"Y;o
} x)GheM^
zBu@a:E%H
9t6c*|60#n
H7z)OaM
K&Bbjb_|
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, Em^~OM3U$q
M=lU`Sm
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 .a7RGT3]m
C=]<R<Xy
么只需要: MkL2I+*
java代码: _U-`/r o
9}m?E<6&
GBT|1c'i
<?xml version="1.0"?> !|UX4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork X^K^az&L
/t`\b
[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- cz{`'VN}`
{\CWoFht>
1.0.dtd"> 0c`nk\vUy
c)B3g.C4m
<xwork> 6h2keyod
V7r_Ubg@K
<package name="user" extends="webwork- JJ%@m;~
CbC[aVA=
interceptors"> /e|Lw4$@S
u!5q)>Wt(
<!-- The default interceptor stack name `[g$EXX
_+NjfF|
--> 2#sFY/@
<default-interceptor-ref [DH4iG5
$
P5K
name="myDefaultWebStack"/> Pd\4hy
Fa[^D~$l*
<action name="listUser" )Uy%iE*
!Q15qvRS
class="com.adt.action.user.ListUser"> *DC/O(
0
<param I;%1xdPt
\X _}\_c,d
name="page.everyPage">10</param> _uLpU4# ?
<result BDvkY
,]7ouH$H}
name="success">/user/user_list.jsp</result> HI 1T
</action> 7Q9Hk(Z9
OKlR`Vaty
</package> D
5n\h5
] xHiy+
</xwork> H-+U^@w
nJ]7vj,rB
4
ZnQpKg
GdI,&|/
Zk((VZ(y
R20 .dA_N
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 G3io!XM)D
/MY's&D(
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。 vj%"x/TP
#e-K It
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 QK[^G6TI
$f0u
19qHWU^0V
Pz{MYw
4KtD
k
我写的一个用于分页的类,用了泛型了,hoho oI/_WY[t
][jwy-Uy;
java代码: ; _c&J&I
=VzJ>!0
j \jMN*dmV
package com.intokr.util; hmGlGc,lf
Ye&/O<G'V
import java.util.List; \-pwA j?
i/+^C($'f
/** Os'E7;:1h
* 用于分页的类<br> //BJaWq
* 可以用于传递查询的结果也可以用于传送查询的参数<br> [|oG}'Xz
* 1C{0 R.
* @version 0.01 C/Tk`C&
* @author cheng N=C t3
*/ `e<IO_cg
public class Paginator<E> { JX&]>#6|E
privateint count = 0; // 总记录数 m;l[flQ~
privateint p = 1; // 页编号 0*b8?e
privateint num = 20; // 每页的记录数 jH9PD8D\
privateList<E> results = null; // 结果
~deS*
pI-Qq%Nwt
/** U1y!R<qlp
* 结果总数 v1~l=^4&
*/ H`)eT6:|/
publicint getCount(){ Q4-d|
return count; `WOoC
} ftTD-d
.O1w-,=
publicvoid setCount(int count){ nMzt_Il I
this.count = count; Hq 5#.rZ#
} ejZ-A?f-K
y,`n9[$K\
/** =K} Pfh
* 本结果所在的页码,从1开始 PL&>pM
* pJ}U'*Z2
* @return Returns the pageNo. l+F29_o#
*/ }.)R#hG?
publicint getP(){ Kt*fQ
`9
return p; / ^d9At614
} ^6kl4:{idE
Z40k>t
D
/** nc:/GxP
* if(p<=0) p=1 g 4=1['wW
* t;VMtIW+E
* @param p c=\ _[G(
*/ _]o7iqtv
publicvoid setP(int p){ iXo;e
if(p <= 0) VQH48{X
p = 1; [k\VUg:P
this.p = p; Zqm%qm:
} X5/j8=G H`
'uL$j=vB
/** yg'CL/P
* 每页记录数量 W`9{RZ'
*/ vw!7f|Pg ~
publicint getNum(){ "KK}}$>
return num; ,H"}Rw
} 1q!k#Cliu
1$03:ve1
/** KyX2CfW}t
* if(num<1) num=1 C('D]u$Hdk
*/ &%j`WF4p
publicvoid setNum(int num){ _0rt.NRD
if(num < 1) qzxWv5UH
num = 1; 5A`>3w{3n
this.num = num; 0Sd>*nC
} L]z8'n,
YT!iI
/** @-S7)h>~
* 获得总页数 :2c(.-[`
*/ 6/L[`n"G
publicint getPageNum(){ _VdJFjY?zc
return(count - 1) / num + 1; >$rH,Er
} +
>dC
Uz_ob9l<#H
/** D.{vuftu
* 获得本页的开始编号,为 (p-1)*num+1 ==?wG!v2 h
*/ Q3l>xh
publicint getStart(){ |+Rx)
return(p - 1) * num + 1; jbS@6 *_
} h/\Zq
OXM=@B<"
/** S;Sy.Lp
* @return Returns the results. lH_pG ~
*/ >ph=?MKD
publicList<E> getResults(){ E]~#EFc
return results; z. hq2v
} U9`Co&Z2
4uO88[=
public void setResults(List<E> results){ xM<aQf\j
this.results = results; ?SYmsaSr5
} ,x&WE@tD|
@*xP A
public String toString(){ t&43)TPb.
StringBuilder buff = new StringBuilder U`~L}w"
Pl'lmUR
(); E.m2- P;4
buff.append("{"); h#UPU7;
buff.append("count:").append(count); Z<d=v3q
buff.append(",p:").append(p); \\R<HuTY
buff.append(",nump:").append(num); {f4jE#a>v
buff.append(",results:").append _X?_|!;J
[^a7l$fmi
(results); C~>0K,C0^
buff.append("}"); sSKD"
return buff.toString(); C3=0st$
} \bF<f02P
R$u1\r1I
} F7C+uGTs
4Hf'/%kW
XLiwE$:t%