Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 VUI|.76g
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 C7H/N<VAq
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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 XUuu-wm:}
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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 ljKrj
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分页支持类: 5OoN!TEM
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java代码: :VF<9@t
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package com.javaeye.common.util; ['%69dPh
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import java.util.List;
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publicclass PaginationSupport { &-5_f*{
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publicfinalstaticint PAGESIZE = 30; rp5(pV7*
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privateint pageSize = PAGESIZE; RxMH!^
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privateList items; -{`@=U
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privateint totalCount; c{[q>@y
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privateint[] indexes = newint[0]; Fq9Q+RNMZL
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privateint startIndex = 0; 9<Kj6t_
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public PaginationSupport(List items, int ,t)x{I;C)
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totalCount){ 0@2mXO9f"
setPageSize(PAGESIZE); !~Q2|r
setTotalCount(totalCount); IF]lHB
setItems(items); Cuc$3l(%
setStartIndex(0); Agrp(i"\@
} n ]dL?BJ
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public PaginationSupport(List items, int p _d:eZ
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totalCount, int startIndex){ GWvH[0
setPageSize(PAGESIZE); 9}z0J
setTotalCount(totalCount); QM?#{%31
setItems(items); XT;u<aJs
setStartIndex(startIndex); o!Rd ^
} 'Wa,OFd\8
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public PaginationSupport(List items, int 1".v6caW
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totalCount, int pageSize, int startIndex){ mqq;H}
setPageSize(pageSize); Qv-@Zt!8
setTotalCount(totalCount); 97)/"i e
setItems(items); :W@#) 1=
setStartIndex(startIndex); 85;b9k&\M
} GJqE!I,.
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publicList getItems(){ TNJG#8 n%Y
return items; MQKfJru7
} \p%3vRwS%p
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publicvoid setItems(List items){ UU8pz{/
this.items = items; HK+/:'Pu
} +{]xtQB=,{
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publicint getPageSize(){ Q]o C47(
return pageSize; ItVugI(^ C
} $H$j-)\D
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publicvoid setPageSize(int pageSize){ !;_H$r0
this.pageSize = pageSize; cwV]!=RtO
} 5[n(7;+gw
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publicint getTotalCount(){ h~wi6^{&Y
return totalCount; 5{$LsL
} OxGE%R,
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publicvoid setTotalCount(int totalCount){ W[+|}
if(totalCount > 0){ V(Yxh+KU
this.totalCount = totalCount; %7g:}O$
int count = totalCount / 1wW)tNKIF
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pageSize; &QNWL]
if(totalCount % pageSize > 0) l1]p'Liuu
count++; s}onsC
indexes = newint[count]; &F}"Z(B<wK
for(int i = 0; i < count; i++){ N$[$;Fm:
indexes = pageSize * lgpW@g
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i; ~afg)[(
} q$G,KRy/
}else{ jgS%1/&
this.totalCount = 0; ]59i>
} c]B$i*t
} -YD+(c`l
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publicint[] getIndexes(){ jp' K%P
return indexes;
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} Nm):9YQ/
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publicvoid setIndexes(int[] indexes){ _Jv
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this.indexes = indexes; &Z?ut*%S
} ,#W
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publicint getStartIndex(){ |y20Hi':
return startIndex; m5G \}8|
} 2&Nb
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publicvoid setStartIndex(int startIndex){ -*2Mf Mh
if(totalCount <= 0) &_5tqh
this.startIndex = 0; 1c+]gIe
elseif(startIndex >= totalCount) {YUIMd!Y
this.startIndex = indexes [7m1Q<
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[indexes.length - 1]; I]!^;))
elseif(startIndex < 0) d2s OYCKe
this.startIndex = 0; g]UBZ33y
else{ r}yG0c,
this.startIndex = indexes %r)avI
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[startIndex / pageSize]; 3?E8\^N\n
} rw)kAe31
} /MQU
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publicint getNextIndex(){ OdI\B
int nextIndex = getStartIndex() + Hx$c
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pageSize; *c[2C
if(nextIndex >= totalCount) S]sk7
return getStartIndex(); %7`f{|.
else !QmzrX}h
return nextIndex; qW 1V85FG
} y$hp@m'@C
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publicint getPreviousIndex(){ TO,rxf
int previousIndex = getStartIndex() - `IINq{Zk
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pageSize; A$g+K,.l
if(previousIndex < 0) G1 o70
return0; ^7]"kg DA
else fQ>4MKLw=d
return previousIndex; ]aCk_*U
} pS 4&w8s
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} eK /?%t
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抽象业务类 t]1ubt2W
java代码: T2?HRx
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/** 1G~S|,8p
* Created on 2005-7-12 aKF*FFX
*/ Q-rL$%~='
package com.javaeye.common.business; Y<\^7\[x
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import java.io.Serializable; cD1o"bq
import java.util.List; &$`hQgi
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import org.hibernate.Criteria; *5$&`&,
import org.hibernate.HibernateException; AgF5-tz6x
import org.hibernate.Session; +)nT|w45
import org.hibernate.criterion.DetachedCriteria; iV.p5FD
import org.hibernate.criterion.Projections; .'[/|4H
import ,G^[o,hS
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org.springframework.orm.hibernate3.HibernateCallback; i54md$Q^
import ^C&+
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org.springframework.orm.hibernate3.support.HibernateDaoS 4"\yf
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upport; ANH4IYd3
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import com.javaeye.common.util.PaginationSupport; 151tXSzLT
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public abstract class AbstractManager extends x2|6
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HibernateDaoSupport { ,gnQa
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privateboolean cacheQueries = false; !a1i Un9
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privateString queryCacheRegion; `29TY&p+"
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publicvoid setCacheQueries(boolean LU!1s@
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cacheQueries){ ")s!L"x
this.cacheQueries = cacheQueries; Q"a2.9Eo
} |c-LSs'\
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publicvoid setQueryCacheRegion(String cTZ)"^z!
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queryCacheRegion){ >Pe:I
this.queryCacheRegion = 5IMSNGS
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queryCacheRegion; 1TqF6`;+
} X7aXxPCq1
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publicvoid save(finalObject entity){ <z#BsnjW{
getHibernateTemplate().save(entity); #G_/.h@
} coQ[@vu
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publicvoid persist(finalObject entity){ 6i@ub%qq
getHibernateTemplate().save(entity); zjbE 7^N
} ?)A2Kw>2
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publicvoid update(finalObject entity){ y[HQBv
getHibernateTemplate().update(entity); *)VAaGUX>
} 7{BnXN[
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publicvoid delete(finalObject entity){ fDuwgY0
getHibernateTemplate().delete(entity); @vH2Vydu
} 5ouQQ)vA
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publicObject load(finalClass entity, *M!kA65'
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finalSerializable id){ ./maY1>T
return getHibernateTemplate().load 9EgP9up{6!
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(entity, id); :k!j"@r
} X7cWgo66T
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publicObject get(finalClass entity, *m_93J
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finalSerializable id){ u7k|7e=xk
return getHibernateTemplate().get ?R?Grw)`H
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(entity, id); ^tE_LL+ji|
} )*[
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publicList findAll(finalClass entity){ g3rRhS
return getHibernateTemplate().find("from w??c1)
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" + entity.getName()); Pf8u/?/
} x YT}>#[
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publicList findByNamedQuery(finalString +Jw{qQR/*
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namedQuery){ 6GOg_P
return getHibernateTemplate $r"A@69^RS
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().findByNamedQuery(namedQuery); <|JU(B
} a%n'%*0
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publicList findByNamedQuery(finalString query, v |ifI
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finalObject parameter){ u{+!&
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return getHibernateTemplate 6^ik|k|
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().findByNamedQuery(query, parameter); <3Fz>}V32
} J9a $AU*
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publicList findByNamedQuery(finalString query, Qtnv#9%Vi
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finalObject[] parameters){ ;.0LRWcJ
return getHibernateTemplate `e*61k5
b Fn(w:1Q
().findByNamedQuery(query, parameters); QT_^M1%
} )d_U)b7i
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publicList find(finalString query){ #ko6L3Pi
return getHibernateTemplate().find sy.:T]ZH
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(query); AY@k-4
} 5Jd`
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publicList find(finalString query, finalObject -R74/GBg
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parameter){ ~*kK4]lP
return getHibernateTemplate().find bZXlJa`'S
. =R=cA7
(query, parameter); 5*XH6g F
} _Ff".t<"
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public PaginationSupport findPageByCriteria ]0YDb~UB
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(final DetachedCriteria detachedCriteria){ hOn
return findPageByCriteria h{H]xe[Q
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); K
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} }
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public PaginationSupport findPageByCriteria 'F<Sf:?.p
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(final DetachedCriteria detachedCriteria, finalint &&*wmnWCS{
[[$Mh_MD
startIndex){ dL(4mR8
return findPageByCriteria D0KELAcY
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(detachedCriteria, PaginationSupport.PAGESIZE, E]?2!)mgce
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startIndex); yW:AVqE)t
} )Kr(Y.w
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public PaginationSupport findPageByCriteria iI}nW
@M9_j{A
(final DetachedCriteria detachedCriteria, finalint >!<V\
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pageSize, b2W; |
finalint startIndex){ I'P.K| "R
return(PaginationSupport) | 4%v"U
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getHibernateTemplate().execute(new HibernateCallback(){ LsnXS9_
publicObject doInHibernate >7W"giWP
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(Session session)throws HibernateException {
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Criteria criteria = nT)~w
s
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detachedCriteria.getExecutableCriteria(session); 8@Q"YA3d+
int totalCount = iAg}pwU
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((Integer) criteria.setProjection(Projections.rowCount R,XD6' Q
bf{Ep=-
()).uniqueResult()).intValue(); VgUvD1v?}
criteria.setProjection hN!.@L
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(null); m/cx|b3hqv
List items = l; */M.B
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criteria.setFirstResult(startIndex).setMaxResults S[ i$e
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(pageSize).list(); rC~_:uXtE
PaginationSupport ps = ,Qga|n8C
^75pV%<%
new PaginationSupport(items, totalCount, pageSize, .!9Vt#
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startIndex); i^~sn `o
return ps; v)TUg0U=,
}
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}, true); &C\=!r0j^
} ;%M2x5
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public List findAllByCriteria(final bW}b<(y
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DetachedCriteria detachedCriteria){ `AB~YX%(
return(List) getHibernateTemplate '! #On/
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().execute(new HibernateCallback(){ ]U#JsMS
publicObject doInHibernate 6_x}.bkIx=
T %$2k>
(Session session)throws HibernateException { Z+OAs0}mV
Criteria criteria = T<!\B]
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detachedCriteria.getExecutableCriteria(session); o$*bm6o
return criteria.list(); Q=dw 6
} oA5<[&~<
}, true); OA\vT${5
} %-T}s`Z
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public int getCountByCriteria(final &9S8al
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DetachedCriteria detachedCriteria){ @#'yPV1
Integer count = (Integer) z&\Il#'\m+
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getHibernateTemplate().execute(new HibernateCallback(){ cu)@P 0I
publicObject doInHibernate tj`tLYOZ@-
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(Session session)throws HibernateException { ))8Emk^Q{
Criteria criteria = )zo#1$C-
= E##},N"
detachedCriteria.getExecutableCriteria(session); L.R"~3
return IS3e|o*]MP
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criteria.setProjection(Projections.rowCount GG@iKL V
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()).uniqueResult(); $1:}(nO,
} 9[6G8;<D&
}, true); r _{)?B
return count.intValue(); j=`y
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} {ILp[&sL
} \HBVNBY
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用户在web层构造查询条件detachedCriteria,和可选的 Q"x`+?!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &ryl$!!3H
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PaginationSupport的实例ps。 Uqb]e?@
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ps.getItems()得到已分页好的结果集 9Ba%=
ps.getIndexes()得到分页索引的数组 JNU"5sB
ps.getTotalCount()得到总结果数 O6*'gnke
ps.getStartIndex()当前分页索引 *
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ps.getNextIndex()下一页索引 v9X7-GJ~
ps.getPreviousIndex()上一页索引 :HQ8M*o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -N /8Ho
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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 "t3uW6&
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一下代码重构了。 y@2vY[)3s
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我把原本我的做法也提供出来供大家讨论吧: Huc3|~9
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首先,为了实现分页查询,我封装了一个Page类: j3sz*:
java代码: >x|A7iWn{,
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/*Created on 2005-4-14*/ 2
package org.flyware.util.page; 0{^l2?mgSb
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/** :V5!C$QV
* @author Joa wI1M0@}PV
* Fyi?,,
*/ y{&{=1#
publicclass Page { |,M#8NOp:
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/** imply if the page has previous page */ : pE-{3I
privateboolean hasPrePage; +Tgy,oD0
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/** imply if the page has next page */ Mdy0!{d
privateboolean hasNextPage; S?,KgMVM
.&*
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/** the number of every page */ =DmPPl{
privateint everyPage; (IO\+
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/** the total page number */ V)WIfRs
privateint totalPage; b7>-aem@I
$w";*">:0
/** the number of current page */ 1%]{0P0?[
privateint currentPage; kp#c:ym
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/** the begin index of the records by the current On2Vf*G@|
~8Dd<4?F]
query */ M;S-ESQ
privateint beginIndex; U&d-? PI
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/** The default constructor */ RpaA)R,
public Page(){ $@ T6g
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} Z7KB?1{G
b& _i/n(
/** construct the page by everyPage ~PH1|h6
* @param everyPage E:dT_x<Y
* */ a-UD_|!
public Page(int everyPage){ (Ay4B*|!
this.everyPage = everyPage; g O\f:Pg
} |aOnV,}
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/** The whole constructor */ D/!eov4"
public Page(boolean hasPrePage, boolean hasNextPage, Js^r]=\F'
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p[k9C$@e}
int everyPage, int totalPage, +"N<-
int currentPage, int beginIndex){ ~YT>:Np
this.hasPrePage = hasPrePage; (`uC"M Lk
this.hasNextPage = hasNextPage; o<Rxt
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this.everyPage = everyPage; n_!]B_Vd$
this.totalPage = totalPage; ([4{n
this.currentPage = currentPage; f Dm}J
this.beginIndex = beginIndex; u[6`Jr~
} (-G(^Tn
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/** A]~i uUHm
* @return 8en#PH }
* Returns the beginIndex. 6wvhvMkS
*/ +~pc%3*
publicint getBeginIndex(){ !!D:V`F/d
return beginIndex; ytBxe]
} yrK--C8
tKqCy\-q
/** Ig?.*j ]
* @param beginIndex NdED8 iRc
* The beginIndex to set. )lngef
/D_
*/ WSpg(\Cs
publicvoid setBeginIndex(int beginIndex){ aBA#\eV
this.beginIndex = beginIndex; 2dV\=vd
} 83 ^,'Z
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/** o"+&^
* @return 7gR;
* Returns the currentPage. ` $x#_-Hn
*/ o._#=7|(
publicint getCurrentPage(){ 7+Jma! o
return currentPage; &0<R:K ?>N
} 7yCx !P;
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/** p6eDd"Y
* @param currentPage c402pj
* The currentPage to set. oe_[h]Hgl
*/ 5KPPZmO
publicvoid setCurrentPage(int currentPage){ G]3ML)l
this.currentPage = currentPage; :Ro"
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} F#37Qv
*mhw5Z=!
/** Uub%s`O
* @return gJ[q
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* Returns the everyPage. 'r?HL;,q
*/ MFdFZkpiV
publicint getEveryPage(){ eJ)KE5%n#
return everyPage; 0f#a_
} ]zR;%p
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/** 0|+hm^'_
* @param everyPage :M?')
* The everyPage to set. !&:W1Jkp(
*/ /*p?UW<*4
publicvoid setEveryPage(int everyPage){ Ai_|)
this.everyPage = everyPage; q!h*3mNm
} 02c.;ka3
[Jh))DIx
/** >fzzrD}]
* @return kFZu/HRI
* Returns the hasNextPage. >zx50e)
*/ u.K'"-xt4K
publicboolean getHasNextPage(){ 'FA)LuAok
return hasNextPage; TboHP/
} L!Zxc~
t:j07 ,1~
/** 6%hEs6-R
* @param hasNextPage [,?A$Z*Z|
* The hasNextPage to set. f+88R=-u6S
*/ .$s|T
publicvoid setHasNextPage(boolean hasNextPage){ nF
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this.hasNextPage = hasNextPage; xbH!:R;
} -N!soJ<
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/** aKU8"
5
* @return cM'[;u
* Returns the hasPrePage. lG^nT
*/ wNZS6JF.d
publicboolean getHasPrePage(){ S$_Ts1Ge6
return hasPrePage; -clg'Aa;.
} N*)8L[7_;
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/** ghd[G}
* @param hasPrePage j
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* The hasPrePage to set. Ty`=U>K|
*/ ~322dG
publicvoid setHasPrePage(boolean hasPrePage){ UU~;B
this.hasPrePage = hasPrePage; K~~*M?.Z
} cw-JGqLx
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/** KdQ|$t
* @return Returns the totalPage. FbNQ
* ^WYG?/{4
*/ EjCzou
publicint getTotalPage(){ -+2xdLa63
return totalPage; d1_*!LW$
} JRs[%w`kD
uC ;PP=z
/** q@yabuN@,j
* @param totalPage _I"<?sh3
* The totalPage to set. k.f:nv5JO
*/ iP\&fZY_
publicvoid setTotalPage(int totalPage){ I8wVvs;k
this.totalPage = totalPage; E6\~/=X=%
} [?o vJ
{'bkU9+
} TZ_'nB~
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4!W?z2ly~R
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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 &zDFf9w2{
}(IDPaJ
个PageUtil,负责对Page对象进行构造: \B+SzW
java代码: `fh_8%m]*
on&=%tCAL
Y-k~ 7{7
/*Created on 2005-4-14*/ nk.Eq[08
package org.flyware.util.page; f3B8,>
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import org.apache.commons.logging.Log; ^u&Khc~
y
import org.apache.commons.logging.LogFactory; "r3s'\
7n]%`Yb
/** nM}`H'0
* @author Joa $6%;mep
* 9rc
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*/ j@\/]oL^We
publicclass PageUtil { 'UCx^-
Gf.o{
privatestaticfinal Log logger = LogFactory.getLog #u(,#(P'#
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(PageUtil.class); X.5LB!I)
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/** J~`%Nj5>
* Use the origin page to create a new page $F$R4?_
* @param page UeeV+xU
* @param totalRecords Pt;Ahmi
* @return RIx6& 7$
*/ iFchD\E*o
publicstatic Page createPage(Page page, int UHHKI)(
.[s82c]]6
totalRecords){ Tz~ftf
return createPage(page.getEveryPage(), +>({pHZ<S
!Hj)S](F
page.getCurrentPage(), totalRecords); |^!@
} 5W-M8dc6
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/** rmJ847%y`
* the basic page utils not including exception .?]_yX
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50@B]
handler }-iOYSn
* @param everyPage kfECC&"
* @param currentPage K7Tell\`
* @param totalRecords JPKZU<:+V
* @return page M&-/&>n!
*/ "A3xX&9-q
publicstatic Page createPage(int everyPage, int ?"u-@E[m
Ux]@prA q
currentPage, int totalRecords){ 1yc@q8
everyPage = getEveryPage(everyPage); ~[6|VpGc:
currentPage = getCurrentPage(currentPage); !qv;F?2
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int beginIndex = getBeginIndex(everyPage, k] YGD
fdHxrH>*
currentPage); y5h[^K3
int totalPage = getTotalPage(everyPage, oPZ4}>uV
y Dw!u[:
totalRecords); sRnMBW.
boolean hasNextPage = hasNextPage(currentPage, wB"Gw` D
5(Oc"0''H
totalPage); FQl|<l6
boolean hasPrePage = hasPrePage(currentPage); AW68'G*m
hKYPH?b%
returnnew Page(hasPrePage, hasNextPage, :E*U*#h/
everyPage, totalPage, NWj@iyi<
currentPage, )5x?Qn (B
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beginIndex); A[a+,TN{
} P://Zi6>
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privatestaticint getEveryPage(int everyPage){ ,BAF?}04=
return everyPage == 0 ? 10 : everyPage; Z8UM0B=i
} -C<aB750O)
r U5'hK
privatestaticint getCurrentPage(int currentPage){ #IDCCD^1=
return currentPage == 0 ? 1 : currentPage; UlytxWkUX
} >^N:A
gp2)35
privatestaticint getBeginIndex(int everyPage, int {*Pp^r
![%,pip2/&
currentPage){ _r'M^=yx[
return(currentPage - 1) * everyPage; 3J<,2
} {Wo7=aR
TaG-^bX8B
privatestaticint getTotalPage(int everyPage, int wYG0*!Vj
3}Qh`+Yj]
totalRecords){ K4~Ox
int totalPage = 0; 5Bo)j_Qo
Z]d]RL&r
if(totalRecords % everyPage == 0) YZ@-0_Z
totalPage = totalRecords / everyPage; \f#ao<vQm
else Ymom 0g+f
totalPage = totalRecords / everyPage + 1 ; :DJ@HY
w4a7c
return totalPage; 5;Xrf=
} 6Tnzg`0I
]9Hy
"#Fz
privatestaticboolean hasPrePage(int currentPage){ Ea?.HRxl
return currentPage == 1 ? false : true; Ags`%(
} <&iBR
g!ww;_
privatestaticboolean hasNextPage(int currentPage, cK&oC$[r-
=@o}
int totalPage){ 63=m11Z4
return currentPage == totalPage || totalPage == 'o L8Z
;\N*iN#K
0 ? false : true; $EF@x}h:A
} d.A0(*k,
M-Bw9`#Jw
flqTx)xE
} 5@ug1F&
wn&2-m*a
mZyTo/\0
wQT'~'kL
6*7&X#gG
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。 _L":Wux
bSfQH4F
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 ZI7<E
!=:c8V
做法如下: [eRMlSXA
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 r;z A `
5,C,q%2
的信息,和一个结果集List: Df (6DuW
java代码: t=AR>M!w~
M %~kh"
Hik[pVK@
/*Created on 2005-6-13*/ 9&cZIP
package com.adt.bo; .E&~]<
kns]P<g
import java.util.List; |+;"^<T)l
2B7&Ll\>
import org.flyware.util.page.Page; )Yml'?V"
o6 /?WR 9
/** Cmj)CJ-
* @author Joa q@:&^CS
*/ LxT ]-
publicclass Result { YVT^}7#
DZue.or
private Page page; }8HLyK,4
i7FEjjGtG
private List content; :z\STXq
\+xsJbEV
/** 4"sP= C
* The default constructor $4&Ql
*/ `c(@WK4
public Result(){ rzu^br9X
super(); ;QYK {3R?
} q)*0G*
ArY'NE\Htt
/** #=rR[:M
* The constructor using fields 7F.,Xvw&@
* iwbjjQPr
* @param page V~;YV]1Y
* @param content S4w/
kml3
*/ iX=*qiVX
public Result(Page page, List content){ Qxwe,:
this.page = page; 5WUrRQ?E
this.content = content; C7{w I`~
} x+pFu5,
Ero3A'f
/** S~T[*Z/m
* @return Returns the content. X6)LpMm
*/ SpgVsz
publicList getContent(){ PsLCO(26
return content;
!ZRV\31%
} iQKfx#kt
om1 /9
/** XL:7$
* @return Returns the page. *XJSa
*/ i+;EuHf
public Page getPage(){ AF@C9s
return page; _PIk,!<
} hXCDlCO
.NKN2
/** 4:.M*Dz
* @param content /SiQw7yp%
* The content to set. ^N]*Zf~N?
*/ oW6.c]Vo
public void setContent(List content){ @:63OLlrG
this.content = content; |s:!LU&OL\
}
Dg@6o
LE;c+(CAU
/** qVfOf\x.e
* @param page *$QUE0
* The page to set. 5J,vH[E
*/ @bZb#,n]
publicvoid setPage(Page page){ PJ'l:IU
this.page = page; rZLMYM
} O'k"6sBb
} b#sO1MXv
ZM" t.
:z[SI{Y
<%5ny!]
M<SZ7^9<
2. 编写业务逻辑接口,并实现它(UserManager, [lf[J&}X
m\(a{x
UserManagerImpl) w"~T5%p
java代码: hYLu
]?^mb n
BsJClKp/
/*Created on 2005-7-15*/ uZfo[_g0S
package com.adt.service; j0J6ySlY
8=d9*lm
import net.sf.hibernate.HibernateException; \|M z'*
di|l?l^l
import org.flyware.util.page.Page; Cd4G&(=
B#=dz,}
import com.adt.bo.Result; rB4]TQ`c
G]{)yZ'}
/** dQ<EDtap
* @author Joa l{<@[foc
*/ u!O)\m-
publicinterface UserManager { +:b|I'S
r_QWt1K
public Result listUser(Page page)throws ~sOAm
E11"uWk`
HibernateException; CGQ`i
NOvN8.K%
} .A E(D7d6
Yv>% 5`
=dPrG=A
+S$x}b'5q
]c08`
java代码: v''$qMQ)
MZ0 J/@(
5( 3tPbm{
/*Created on 2005-7-15*/ GE|V^_|i
package com.adt.service.impl; vV%w#ULxE~
G3q\Z`|3h
import java.util.List; u
BvN*LQ
Kg56.$
import net.sf.hibernate.HibernateException; 2vynz,^ET
4v;/"4)'
import org.flyware.util.page.Page; 7v{Dwg
import org.flyware.util.page.PageUtil; ct`89~"
&U:;jlST9
import com.adt.bo.Result; $aEL>,X
import com.adt.dao.UserDAO;
W+e
import com.adt.exception.ObjectNotFoundException; ikUG`F%W
import com.adt.service.UserManager; 8< R#}
W_%Dg]l
/** 6:H@=fEv
* @author Joa %5'6^bT
*/ tks1*I$S<
publicclass UserManagerImpl implements UserManager { &4LrV+`$V
yTv#T(of
private UserDAO userDAO; L:7%W dyh
3{CXIS
/** p~qdkA<
* @param userDAO The userDAO to set. "~XAD(T6
*/ alyWp
publicvoid setUserDAO(UserDAO userDAO){ ol-U%J
this.userDAO = userDAO; G#UO>i0jy
} *~cq
(PFQ
O.i.<VD7
/* (non-Javadoc) C1hp2CW$5/
* @see com.adt.service.UserManager#listUser n}EH{k9#
A\LMmg
(org.flyware.util.page.Page) Q/I/>6M7UZ
*/ H>%K}Fh
public Result listUser(Page page)throws nwf(`=TC
O|d"0P
HibernateException, ObjectNotFoundException { ;tlvf?0!
int totalRecords = userDAO.getUserCount(); "_W[X
if(totalRecords == 0)
`ml
throw new ObjectNotFoundException L\aG.\
}gete'I
("userNotExist"); r[K%8Y8`
page = PageUtil.createPage(page, totalRecords); W|4:3c4
List users = userDAO.getUserByPage(page); R10R,*6>
returnnew Result(page, users); vr"O9L
w
} 0tK(:9S
xcty
} PY[nnoF"|
0l;TZf=H
P`^nNX]x+,
kZ$2Uss
@cukoLAn
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]V^ >aUlj
HQX.oW
询,接下来编写UserDAO的代码:
Z/RSZ-
3. UserDAO 和 UserDAOImpl: s^#B*
java代码: #ozui-u>
n&1q*
NYw>Z>TD8c
/*Created on 2005-7-15*/ g=n{G@ *N
package com.adt.dao; ^M0
]jjHIFX
import java.util.List; zc K`hS
{u~JR(C:
import org.flyware.util.page.Page; ]lqLC
9(6f:D
import net.sf.hibernate.HibernateException; 3N257]
Lcb5^e?'Q
/** r'8qZJgm
* @author Joa HAwdu1$8
*/ 5X&Y~w,poU
publicinterface UserDAO extends BaseDAO { 2u Zb2O
_0}u0fk
publicList getUserByName(String name)throws Ogv9_X8
>e>%AMzo[
HibernateException; m~04I~8vk
F/V-@SF
publicint getUserCount()throws HibernateException; bI+/0Xx
&n9&k
Em
publicList getUserByPage(Page page)throws ,Wv+Ek
~[<C6{
HibernateException; #zRHYZc'T|
5\V""fH
} KT[ZOtu
K
@RGvP
DQ<4`wE M
nr&bpA/
ijP`fM8
java代码: .exBU1Yk@
uP G\1
ml@;ngmp.
/*Created on 2005-7-15*/ `J]e.K
package com.adt.dao.impl; u8.F_'` z
_AzI\8m
import java.util.List; .do8\
>
a;iX.K
import org.flyware.util.page.Page; zzK<>@c
90#* el
import net.sf.hibernate.HibernateException; <2N{oK.
import net.sf.hibernate.Query; JR8|!Of@B
'i',M+0>jC
import com.adt.dao.UserDAO; S/"G=^~
7r&lW<:>
/** tk]D)+{u&c
* @author Joa 0<7sM#sI!
*/ auga`*
public class UserDAOImpl extends BaseDAOHibernateImpl Sl/]1[|mb
;4l8Qg
7
implements UserDAO { ?VlGTMaS+
~UJ.A<>Fh
/* (non-Javadoc) HjIIhl?UY
* @see com.adt.dao.UserDAO#getUserByName vJxEF&X
w?>f:2(=[
(java.lang.String) ~| b\1SR
*/ R2v9gz;W
publicList getUserByName(String name)throws !(
>U3N
LaO8)lqR
HibernateException { a*-9n-U@[k
String querySentence = "FROM user in class ( <YBvpt4>
^D<CoxG
com.adt.po.User WHERE user.name=:name"; yX4Vv{g
Query query = getSession().createQuery d(|q&b:
q8_(P&
(querySentence); ynv{
rMl
query.setParameter("name", name); BBM[Fy37!}
return query.list(); ,`JYFh M
} sC.b'1P
n&Ckfo_D
/* (non-Javadoc) \_WR:?l
* @see com.adt.dao.UserDAO#getUserCount() %cLS*=MO
*/ jYi,oE
publicint getUserCount()throws HibernateException { )by7[I0v
int count = 0; Tf~eH!~0
String querySentence = "SELECT count(*) FROM iLch3[p%
.<zKBv
user in class com.adt.po.User"; d\uN
Query query = getSession().createQuery ~n-Px)
XVkw/l
(querySentence); +}O -WX?
count = ((Integer)query.iterate().next #B<EMGH
}[Z'Sg]s
()).intValue(); g3].STz6w
return count; OKAU*}_
} 9j|v
D
+@=V}IO
/* (non-Javadoc) yAfwQ$Ll7
* @see com.adt.dao.UserDAO#getUserByPage s>m2qSu
`Jk0jj6Z
(org.flyware.util.page.Page) 0u1ZU4+EC
*/ QuqznYSY{
publicList getUserByPage(Page page)throws dpTsTU!\
arDl2T,igF
HibernateException { g!R7CRt%
String querySentence = "FROM user in class H,]8[qT<
._^}M<o L
com.adt.po.User"; 0W(mx-[H/
Query query = getSession().createQuery
][wb4$2
]R_R`X?
(querySentence); n9xP8<w8
query.setFirstResult(page.getBeginIndex()) Iz1x| EQ
.setMaxResults(page.getEveryPage()); [a04(
2g
return query.list(); `p&[b]b
} lhKn&U
Hl`OT5pNf
} `*Yw-HL
5>I-? Ki
JcWp14~e
4d`YZNvZW/
qFD ZD)K
至此,一个完整的分页程序完成。前台的只需要调用 3Rc*vVnI
)[ A-d(y=
userManager.listUser(page)即可得到一个Page对象和结果集对象 (iX8YP$ %
!gve]>M
的综合体,而传入的参数page对象则可以由前台传入,如果用 &cL1 EQ(
z~#;[bER
webwork,甚至可以直接在配置文件中指定。 qtExd~E
C<
9x\JY%
下面给出一个webwork调用示例: 2
^m}5:0
java代码: 6@s!J8!
f^FFn32u
7pm'b,J<
/*Created on 2005-6-17*/ "iA0hA
package com.adt.action.user; 3]l)uoNt/
~ubvdQEW
import java.util.List; hI'WfF!X
rW)h?, b
import org.apache.commons.logging.Log; =p8uP5H
import org.apache.commons.logging.LogFactory; BB6[(Z
import org.flyware.util.page.Page; ^O18\a
I.n,TJoz4J
import com.adt.bo.Result; xvV";o
import com.adt.service.UserService; BM<q;;pO
import com.opensymphony.xwork.Action; 9B!Sv/)y!r
mux/\TII
/** uZC=]Ieh
* @author Joa UDHWl_%L
*/ rP:g`?*V
publicclass ListUser implementsAction{ e0TYHr)X>3
}:0_%=)N<
privatestaticfinal Log logger = LogFactory.getLog ob\-OMNs@
K6kz{R%`
(ListUser.class); inWLIXC,
,X.[37
private UserService userService; z:>cQUYl
2aj1IBnz6/
private Page page; 8:$h&aBI
t(u2%R4<d
privateList users; Nap[=[rv
=6u@JpOl
/* `}EnY@*h
* (non-Javadoc) YNr"]SA@ ;
* B&]`OO>O
* @see com.opensymphony.xwork.Action#execute() i>YS%&O?
*/ F_Y]>,U
publicString execute()throwsException{ /'sv7hg+
Result result = userService.listUser(page); w\)K0RN
page = result.getPage(); 3YHEH\60^
users = result.getContent(); 4!IuTPmr
return SUCCESS; ye(b 7CX
} =SJ#6uFS
QQrldc(I
/** "'U^8NA2
* @return Returns the page. 4>d4g\Z0L
*/ $G".PWc
public Page getPage(){ Q;]JVT1
return page; KqK]R6>
} Ymz/:
gJQ#j~'
/** IRN,=
* @return Returns the users. #AJW-+1g.=
*/ =I# pXL
publicList getUsers(){ YnEyL2SuU
return users; NiZfaC6V
} RlOy,/-<
2:38CdkYp
/** '(.5!7?Qc
* @param page h.edb6
* The page to set. TTXF
r
*/ _4by3?<c
publicvoid setPage(Page page){ "`qk}n-
this.page = page; Bgxk>Y
} b j&!$')
0t7N yKU
/** i!a!qE.1
* @param users 287j,'vR
* The users to set. ^B<-.(F
*/ 4fi4F1 f
publicvoid setUsers(List users){ /HdXJL9B
this.users = users; QLJ\>
} L]=]/>jQ6
YK/? mj1x
/** Qc7*p]E&
* @param userService [+\He/M6
* The userService to set. w|f+OlPXq
*/ k8s)PN
publicvoid setUserService(UserService userService){ Cog }a
this.userService = userService; o<nM-"yWb
} In?rQiD9
} hk?i0#7W
A?MM9Y}K
TAYh#T=S
9K$
x2U
z qA>eDx
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, OeQ[-e
N3u06
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 \'2rs152
{,Z|8@Sl%
么只需要: y3efie {J
java代码: OLx;j+p
f&vMv.
^&;,n.X5Z
<?xml version="1.0"?> _WS8I>
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork y3;M$Jr
e#oK%
{A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]WMzWt:L
.i;.5)shsu
1.0.dtd"> LVUA"'6V
/4+L2O[
<xwork> ]Gi&:k
N8nt2r<h
<package name="user" extends="webwork- uihH")Mo
-7!L]BcZ.
interceptors"> V?OTP&+J%
lW"0fZ_x'E
<!-- The default interceptor stack name ~C{:G;Iy0
4rDVCXE
--> "EpH02{i
<default-interceptor-ref XVNJK-B
3/gR}\=
name="myDefaultWebStack"/> +X#6dv$
%oqKpD+
<action name="listUser" &Sg]P
=R:O`qdC4e
class="com.adt.action.user.ListUser"> %f CkR`:
<param '`;=d<'
yMdu
Zmkc
name="page.everyPage">10</param> ;%0kzIvP
<result bj`GGxzOb
iuj%.}
name="success">/user/user_list.jsp</result> b~UWFX#U
</action> a;bmlV04
<cZ/_+H%C
</package> >&\.{ aj
?<F([(
</xwork> &IXmy-w
p9jC-&:
(Q*x"G#4>
V0D&bN*
8Vz!zYl
@_t=0Rc
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 FI: H/e5[
Zrwd
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。 jv v=
wdt2T8`I/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ?#a&eW
-'O|D}
\A^8KVE!
(Zx--2lc
_8 r'R
我写的一个用于分页的类,用了泛型了,hoho _N:$|O#
'+Jy//5?
java代码: v5@4|u3ds
0Sk~m4fj(
w;Azxcw
package com.intokr.util; %AJ9fs4/
V5-!w0{
import java.util.List; %h(%M'm?
ie[X7$@
/** dLGHbeZ[(
* 用于分页的类<br> WL(Y1>|j
* 可以用于传递查询的结果也可以用于传送查询的参数<br> <o9i;[+H-
* tJ_Y6oFm=
* @version 0.01 f?ycZ
* @author cheng @H$8;CRM
*/ J0vQqTaT
public class Paginator<E> { MB:[: nX
privateint count = 0; // 总记录数 \^0>h`[
privateint p = 1; // 页编号 (xvg.Nby
privateint num = 20; // 每页的记录数 Q_p&~ PNy5
privateList<E> results = null; // 结果 iz;5:
N"<.v6Z
/**
E,\)tZ;,
* 结果总数 Id^q!4Th9
*/ IAzFwlO9
publicint getCount(){ .Y2Hd$rs
return count; p&$PsgR
} L8n?F#q
,d*1|oUw
publicvoid setCount(int count){ A",}Ikh='`
this.count = count; oj.J;[-
} G:1QXwq\j
Wm" q8-<<
/** 8.jf6
* 本结果所在的页码,从1开始 [(g2u@
* EdqB4-#7
* @return Returns the pageNo. T~$Eh6
D
*/ D1+1j:m
publicint getP(){ c2Z!Vtd
return p; F,)+9/S&
} [z\baL|
&,8Qe;
/** WI| -pzg
* if(p<=0) p=1 F0&ubspt