Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0pCDEs
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3} l;
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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 gi
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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 0x6@{0
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分页支持类: bf{Ep=-
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java代码: we
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package com.javaeye.common.util; l; */M.B
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import java.util.List; MR[N6E6Mg
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publicclass PaginationSupport { xvHOY:
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publicfinalstaticint PAGESIZE = 30; zabw!@]
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privateint pageSize = PAGESIZE; w:n(pLc<
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privateList items; #dL5x{gV=
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privateint totalCount; yFIl^Ck%
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privateint[] indexes = newint[0]; #V,LNX)
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privateint startIndex = 0; E`U&Z
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public PaginationSupport(List items, int ]Pz|Oi+]
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totalCount){ F%9e@{
setPageSize(PAGESIZE); lrq>TJEcx
setTotalCount(totalCount); (q0No26;(
setItems(items); V,`!rJ
setStartIndex(0); [9'|7fdU
} hYs82P|2Ol
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public PaginationSupport(List items, int <aD'$(N5
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totalCount, int startIndex){ B!$V\Gs
setPageSize(PAGESIZE); cu)@P 0I
setTotalCount(totalCount); # w
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setItems(items); '
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setStartIndex(startIndex); 9<+;hH8J_r
} vQ?MM&6
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public PaginationSupport(List items, int 6tDg3`w>
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totalCount, int pageSize, int startIndex){ R?1idl)
setPageSize(pageSize); ~NTDG
setTotalCount(totalCount); nNkyOaK*4
setItems(items); r _{)?B
setStartIndex(startIndex); IptB.bYc
} GGYX!=]~
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publicList getItems(){ ]?v?Qfh2
return items; ez{P-qB
} Lg\8NtP
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publicvoid setItems(List items){ gPF}aaB6
this.items = items; Nv}U/$$S
} )*q7pO\cty
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publicint getPageSize(){ IBn'iE[>
return pageSize; TyxU6<>4J4
} 9;;]q?*
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publicvoid setPageSize(int pageSize){ My'9S2Y8nv
this.pageSize = pageSize; FN{H\W1cf
} 5?#OR!N
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publicint getTotalCount(){ 0:7v/S!:
return totalCount; r&H=i
} LS R_x$G+t
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publicvoid setTotalCount(int totalCount){ dXf]G6
if(totalCount > 0){ bUY:XmA
this.totalCount = totalCount; p 02nd.R6
int count = totalCount / f}evw K[S
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pageSize; %RfY`n
if(totalCount % pageSize > 0) P>yG/:W;
count++; Zi2Eu4p l{
indexes = newint[count]; =H.<"7
for(int i = 0; i < count; i++){ I{*.htt{
indexes = pageSize * tkm~KLWV&7
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i; rw40<SS"Z
} v%69]a-T
}else{ e{qp!N1!
this.totalCount = 0; +j)-L \
} 2fHIk57jP
} !9ceCnwbNN
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publicint[] getIndexes(){ i"2J5LLv
return indexes; @M1yBN
} &Cx yP_
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publicvoid setIndexes(int[] indexes){ y4)ZUv,}
this.indexes = indexes; =DmPPl{
} @4W\RwD
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publicint getStartIndex(){ HzgQI
return startIndex; \pBYWf
} wHo#%Y,Nmi
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publicvoid setStartIndex(int startIndex){ flm,r<*}
if(totalCount <= 0) P@! Q1pr
this.startIndex = 0; ~]6Oz;~<3
elseif(startIndex >= totalCount) fmZzBZ_
this.startIndex = indexes Kc-A-P &Ry
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[indexes.length - 1];
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elseif(startIndex < 0) $Nt]${0
this.startIndex = 0; mTb2d?NS
else{ CwH)6uA
this.startIndex = indexes 7DHT)9lD/
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[startIndex / pageSize]; 6U,U[MWJ
} $+)x)1
} JUaKj@a|
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publicint getNextIndex(){ i+T0}M<
int nextIndex = getStartIndex() + s6eq?1l3
u[6`Jr~
pageSize; =Y=^]ayO/
if(nextIndex >= totalCount) =%nqMV(y
return getStartIndex(); 6wvhvMkS
else {*5;:QnT
return nextIndex; R(7X}*@X
} g^<q L|
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publicint getPreviousIndex(){ d= T9mj.@
int previousIndex = getStartIndex() - ]=
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pageSize; H $qdU!c
if(previousIndex < 0) DT7-v4Zd
return0; T$8$9D_u
else :BZx)HxQ
return previousIndex; oRJP5Y5na
} (1r>50Ge
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} n9-q5X^e>
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抽象业务类 ` $x#_-Hn
java代码: o._#=7|(
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/** BoiIr[ (
* Created on 2005-7-12 kvO`]>#;$?
*/ %N_S/V0`
package com.javaeye.common.business; Ll E_{||h
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import java.io.Serializable; li'1RKr
import java.util.List; 0.+Z;j
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import org.hibernate.Criteria; W0?Y%Da(4m
import org.hibernate.HibernateException; 51(`wo>LS
import org.hibernate.Session; B6!<@*BI
import org.hibernate.criterion.DetachedCriteria; .]P;fCQmM
import org.hibernate.criterion.Projections; &fNE9peQFa
import S
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org.springframework.orm.hibernate3.HibernateCallback; a518N*]j
import uL2{v
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org.springframework.orm.hibernate3.support.HibernateDaoS qu~"C,
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upport; 0 c'2rx
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import com.javaeye.common.util.PaginationSupport; fOjt` ~ToI
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public abstract class AbstractManager extends #/sE{jm
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HibernateDaoSupport { `GN5QLg#}0
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privateboolean cacheQueries = false; ZtK%b+MBP
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privateString queryCacheRegion; "E[*rnsLN
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publicvoid setCacheQueries(boolean d~f0]O
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cacheQueries){ BMsy}08dQ
this.cacheQueries = cacheQueries; wk
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} ^VYZ%
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publicvoid setQueryCacheRegion(String r
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queryCacheRegion){ xA1pDrfC/
this.queryCacheRegion = 8{=(#]
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queryCacheRegion; %|6Q7'@p
} o6yZ@R
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publicvoid save(finalObject entity){ Fd.d(
getHibernateTemplate().save(entity); | (9FV^_
} l'8wPmy%N
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publicvoid persist(finalObject entity){ Gl:T
getHibernateTemplate().save(entity); AQU: 0
} JNCtsfd
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publicvoid update(finalObject entity){ [<$d@}O
getHibernateTemplate().update(entity); q9]L!V9Rv
} .Sw'Bo!Ee
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publicvoid delete(finalObject entity){ &h[}5
getHibernateTemplate().delete(entity); HKw4}FC*
} > PA,72e
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publicObject load(finalClass entity, ay[*b_f
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finalSerializable id){ C{^@. 8:
return getHibernateTemplate().load z5w|+9U
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(entity, id); fdHxrH>*
} *&MkkI#
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publicObject get(finalClass entity, 5(Oc"0''H
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finalSerializable id){ T0jJp7O
return getHibernateTemplate().get pdq h'+5
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(entity, id);
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} ,BAF?}04=
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publicList findAll(finalClass entity){ 7C^ nk
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return getHibernateTemplate().find("from >^N:A
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" + entity.getName()); iq-o$6Pg
} }FVX5/.'
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publicList findByNamedQuery(finalString 4pv:u:Z
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namedQuery){ IrC=9%pd$R
return getHibernateTemplate L;`t%1
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().findByNamedQuery(namedQuery); l[ k$O$jo
} :B~c>:
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publicList findByNamedQuery(finalString query, CXZeL 1+
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finalObject parameter){ :DJ@HY
return getHibernateTemplate =ndKG5
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().findByNamedQuery(query, parameter); xkovoTzV
} g (k|"g`*
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publicList findByNamedQuery(finalString query, T:$_1I $
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finalObject[] parameters){ ,vPF=wq
return getHibernateTemplate w3D_ c~
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().findByNamedQuery(query, parameters); ri
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} IIkJ"Qg.
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publicList find(finalString query){ Km7
return getHibernateTemplate().find $(U|JR@
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(query); |{T2|iJI
} iXFaQ
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publicList find(finalString query, finalObject oV`sCr5%
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parameter){ 0J~4
return getHibernateTemplate().find iY-dM(_:]
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(query, parameter); M %~kh"
} ZtVa*xl
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public PaginationSupport findPageByCriteria WmA578|l!
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(final DetachedCriteria detachedCriteria){ e=2D^G#qE
return findPageByCriteria @d\F; o<
_q 8m$4
(detachedCriteria, PaginationSupport.PAGESIZE, 0); *C \O]r:'
} AM>:AtY
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public PaginationSupport findPageByCriteria _Gu ;U@
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(final DetachedCriteria detachedCriteria, finalint Y{KJk'xN5W
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startIndex){ w8qI7/
return findPageByCriteria q`P:PRgM
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(detachedCriteria, PaginationSupport.PAGESIZE, duI8^&|
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startIndex); x+pFu5,
} e\<I:7%Rg
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public PaginationSupport findPageByCriteria Ot?rsr
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(final DetachedCriteria detachedCriteria, finalint B !XT:.+
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pageSize, i+;EuHf
finalint startIndex){ )l=j,4nn
return(PaginationSupport) F}X_I
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getHibernateTemplate().execute(new HibernateCallback(){ xInWcQ
publicObject doInHibernate ?CIa)dhu
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(Session session)throws HibernateException { 4T:ZEvdzf
Criteria criteria = /W9=7&R0
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detachedCriteria.getExecutableCriteria(session); &b_duWs
int totalCount = IY'S<)vOY
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((Integer) criteria.setProjection(Projections.rowCount KnuqU2<
{
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()).uniqueResult()).intValue(); s[hD9$VB>
criteria.setProjection [lf[J&}X
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(null); kW"N~Xw)
List items = V{][{5SR
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criteria.setFirstResult(startIndex).setMaxResults d$!ibL#o
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(pageSize).list(); O?@AnkOhn
PaginationSupport ps = l{<@[foc
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new PaginationSupport(items, totalCount, pageSize, zQ6otDZx
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startIndex); oZQu&O'
return ps; .A E(D7d6
} y&UsSS
}, true); gD-<^Q-
} &W1cc#(
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public List findAllByCriteria(final *cf#:5Nl
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DetachedCriteria detachedCriteria){ j
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return(List) getHibernateTemplate O[!]/qP+.
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().execute(new HibernateCallback(){ KcHW>IBxdv
publicObject doInHibernate jVr:O`
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(Session session)throws HibernateException { )<%GHDWL
Criteria criteria = V
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detachedCriteria.getExecutableCriteria(session); Wh,p$|vL
return criteria.list(); {$Qw]?Yv
} W 5-=,t
}, true); EsdA%`
} d4~!d>{n|c
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public int getCountByCriteria(final />H9T[3=
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DetachedCriteria detachedCriteria){ WOh?/F[@u
Integer count = (Integer) J%{>I
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getHibernateTemplate().execute(new HibernateCallback(){ [&51m^
publicObject doInHibernate m)V%l0
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(Session session)throws HibernateException { arm26YA-,
Criteria criteria = af)L+%Q%R
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detachedCriteria.getExecutableCriteria(session); l4RZ!K*X_"
return cJMp`DQzc
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criteria.setProjection(Projections.rowCount )
}(Po_
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()).uniqueResult(); |Y4c+6@_
} ^DD]jx
}, true); 9J*.'Y
return count.intValue(); K9]L>Wj
} ",Mr+;;:[
} 1
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用户在web层构造查询条件detachedCriteria,和可选的 ~7ZWtg;B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 W^k95%zBM
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PaginationSupport的实例ps。 id+ ~ V
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ps.getItems()得到已分页好的结果集 FF #T"y0Y
ps.getIndexes()得到分页索引的数组 IK1'" S|
ps.getTotalCount()得到总结果数 e>0gE`8A
ps.getStartIndex()当前分页索引 8
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;
ps.getNextIndex()下一页索引 u:.w/k%+
ps.getPreviousIndex()上一页索引 *+(rQ";x
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0CO@@`~4
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 o%7-<\qS
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一下代码重构了。 `*6|2
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我把原本我的做法也提供出来供大家讨论吧: eSQkW
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首先,为了实现分页查询,我封装了一个Page类: hC[=e`j
java代码:
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/*Created on 2005-4-14*/ VCfHm"'E8
package org.flyware.util.page; R2v9gz;W
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/** Z#.1p'3qm1
* @author Joa {CV+1kz
* K[kK8i+(
*/ &Ts!#OcB,
publicclass Page { )X-'Q -
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/** imply if the page has previous page */ cI P.5)Ca
privateboolean hasPrePage; 9w- )??
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/** imply if the page has next page */
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privateboolean hasNextPage; )7 q"l3e"u
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/** the number of every page */ +}O -WX?
privateint everyPage; mFg$;F
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/** the total page number */ s]%Cz \
privateint totalPage; f[1cN`|z
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/** the number of current page */ o!:Z?.!
privateint currentPage; 1l$2T
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/** the begin index of the records by the current XjF@kQeM=
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query */ Qn7T{ BW
privateint beginIndex; '{cSWa|
#
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/** The default constructor */ ]R_R`X?
public Page(){ nm@h5ON_
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} :a6LfPEAX
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/** construct the page by everyPage 7Y9#y{v1
* @param everyPage }9+;-*m/
* */ N$6e KJ]
public Page(int everyPage){ .Q%Hi7JMi
this.everyPage = everyPage; ~f h
} y6nP=g|')>
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/** The whole constructor */ se\f be ^0
public Page(boolean hasPrePage, boolean hasNextPage, ^1najUpQ_n
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int everyPage, int totalPage, xj3qOx$
int currentPage, int beginIndex){ Wd:pqhLh
this.hasPrePage = hasPrePage; %rylmioW>
this.hasNextPage = hasNextPage; V4+|D2
this.everyPage = everyPage; 3[ xdls
this.totalPage = totalPage; {Sf[<I
this.currentPage = currentPage; U05;qKgkDF
this.beginIndex = beginIndex; K6kz{R%`
} 2#>;cn\
hZx&j{
/** |}z)>E
* @return )A\
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* Returns the beginIndex. 4rU/2}.q
*/ ( zWBrCX
publicint getBeginIndex(){ <0})%V?-
return beginIndex; X:oOp=y]|
} t3@+idE b
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/** G&ck98
* @param beginIndex yp#!$+a}
* The beginIndex to set. 3YHEH\60^
*/ +>"s)R43
publicvoid setBeginIndex(int beginIndex){ ye(b 7CX
this.beginIndex = beginIndex; pey=zR!
} cUY-
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/** Xs~'M/>
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* @return [Fl_R[o
* Returns the currentPage. JOJ.79CT
*/ BU:;;iV8
publicint getCurrentPage(){ IRN,=
return currentPage; [d`E9&Hv3
} x3q^}sj%
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/** 39v Bsc
* @param currentPage @IL04' \
* The currentPage to set. `?z('FV
*/ B!wN%>U
publicvoid setCurrentPage(int currentPage){ Xdn&%5rI
this.currentPage = currentPage; LCivZ0?|X
}
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/** Z)7{~xq
* @return eC-&.Fl
* Returns the everyPage. |{#St-!-7
*/ `=(<!nXJx
publicint getEveryPage(){ bBi>BP=
return everyPage; v3DK0 MW
} pr<u
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/** ?/.])'&b
* @param everyPage HZ9 >4G3
* The everyPage to set. hkPMu@BI
*/ 2XR!2_)O5
publicvoid setEveryPage(int everyPage){ OeQ[-e
this.everyPage = everyPage; /nO_e
} y6$a:6
-b!?9T?}
/** x// uF
* @return "09v6Tx
* Returns the hasNextPage. <-1:o*8:}
*/ mZiKA-t
publicboolean getHasNextPage(){ fM.#FT??
return hasNextPage; ;Rv WF )
} w[GEm,ZC
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/** vd%AV(]<LJ
* @param hasNextPage H^'%$F?Ss
* The hasNextPage to set. 6$OmOCA%
*/ (VO'Kd
publicvoid setHasNextPage(boolean hasNextPage){ qlM<X?
this.hasNextPage = hasNextPage; P].Eb7I
} f}yRTR GJv
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/** +X#6dv$
* @return qb;b.P?~D$
* Returns the hasPrePage. *-ys}sX
*/ GG%;~4#2
publicboolean getHasPrePage(){ B*:I-5
return hasPrePage; 6D]fDeH\
} #|T"6jJaQ
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/** a(~X
* @param hasPrePage -\p&18K#
* The hasPrePage to set. ]Sj;\Iz
*/ kB?/_a`]
publicvoid setHasPrePage(boolean hasPrePage){ ktPM66`b
this.hasPrePage = hasPrePage; zf8SpQ2~
} u3Z]!l
7(D)U)9h
/** GH':Yk
* @return Returns the totalPage. jv v=
* onmpMU7w
*/ Cgln@Rz
publicint getTotalPage(){ *A`ZcO=
return totalPage; &KBDrJEX
} 0,-]O=
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/** T-yEn&r4)
* @param totalPage :Z/\U*6~
* The totalPage to set. W\-`}{B_/
*/ tJ_Y6oFm=
publicvoid setTotalPage(int totalPage){ @H$8;CRM
this.totalPage = totalPage; /pkN=OBR
} [(a3ljbRX
phG*It}
} '4 d4i
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 G:1QXwq\j
q {}5wM
个PageUtil,负责对Page对象进行构造: 2.</n}g
java代码: CB-;Jqb
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b 1.S21
/*Created on 2005-4-14*/ (e5Z^9X
package org.flyware.util.page; wO.d;SK
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import org.apache.commons.logging.Log; OcWKK!A
import org.apache.commons.logging.LogFactory; PA803R74
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/** #b&tNZ4!_
* @author Joa .3UJ*^(?
* Gjq7@F'
*/ m;4ti9
publicclass PageUtil { "9^b1UH<
M]k Q{(
privatestaticfinal Log logger = LogFactory.getLog %{IgY{X
6ERMn"[_w
(PageUtil.class); \z2y?"\?
OA6i/3 #8
/** a+J>
* Use the origin page to create a new page dHiir&Rd9`
* @param page At<MY`ka
* @param totalRecords e <{d{
* @return {T^D&i# o
*/ Q5dqn"?
publicstatic Page createPage(Page page, int JW><&hY$"
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totalRecords){ 9 4H')(
return createPage(page.getEveryPage(), $X-PjQb1Bb
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page.getCurrentPage(), totalRecords); \kUQe-:he
} 3mYW]
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/** 5tkKd4VfL
* the basic page utils not including exception GTfM *b
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handler h*JN0O<b
* @param everyPage S9$,.aq
* @param currentPage -le^ 5M7
* @param totalRecords 2.Ww(`swL
* @return page [~|k;\2 +
*/ 03|nP$g
publicstatic Page createPage(int everyPage, int (i(E~^O
,)d`_AD+5
currentPage, int totalRecords){ _~CJitR3
everyPage = getEveryPage(everyPage); .eVX/6,
currentPage = getCurrentPage(currentPage); d)biMI}<5
int beginIndex = getBeginIndex(everyPage, a]P%Y.?r
t1
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currentPage); G8w @C
int totalPage = getTotalPage(everyPage, +PsR*T
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totalRecords); _nzq(m1@
boolean hasNextPage = hasNextPage(currentPage, G6>sAOf
la)+"uW
totalPage); fk?!0M6d
boolean hasPrePage = hasPrePage(currentPage); ?(B}w*G~
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returnnew Page(hasPrePage, hasNextPage, By!u*vSev
everyPage, totalPage, "8zMe L
currentPage, BH^*K/^
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{^:
beginIndex); /o6ido
} n2AoEbd
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privatestaticint getEveryPage(int everyPage){ [{xY3WS
return everyPage == 0 ? 10 : everyPage; xA:;wV
} qR2cRepV
1z2v[S&pk
privatestaticint getCurrentPage(int currentPage){ b9i_\
return currentPage == 0 ? 1 : currentPage; BIx*(
} hB\BFVUSn/
twldwuN
privatestaticint getBeginIndex(int everyPage, int XZ$g~r
]!P6Z?
currentPage){ oui0:Vy<
return(currentPage - 1) * everyPage; MMaS
} u}R|q
oliVaavj
privatestaticint getTotalPage(int everyPage, int G&wYV[Ln
p.4Sgeh#
totalRecords){ e>!]_B1ad
int totalPage = 0; H|?r_Ns
:nnch?J_
if(totalRecords % everyPage == 0) VOATza`
totalPage = totalRecords / everyPage; at*DYZBjDB
else '5T:*Yh
totalPage = totalRecords / everyPage + 1 ; HH(2
5f@&XwD9
return totalPage; \Z%_dT}
} !VG
]~lc
srImk6YD
privatestaticboolean hasPrePage(int currentPage){ (l2n%LL]*
return currentPage == 1 ? false : true; *$('ous8
} V*%><r
yg|yoL'g
privatestaticboolean hasNextPage(int currentPage, O py{i#>
0!:%Ge_
int totalPage){ !]7L9TGn
return currentPage == totalPage || totalPage == 65+2+p
brCL"g|}
0 ? false : true; ct(euPU
} R>[G6LOG
'2<N_)43$
<1~_nt~(*
} K7q R
*'n=LB8R
URr{J}5
a(`"qS
Qq.Ja%Zq
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。 v)zxQuH]^
&y3;`A7,
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;a~/T
mLHl]xs4
做法如下: E.x<J.[Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .36]>8
)o::~ eu
的信息,和一个结果集List: &D7Mv5i0@
java代码: OR10IS
\&v)#w
#Y'ub
5s
/*Created on 2005-6-13*/ HIlTt
package com.adt.bo; BDi+*8
wFL7JwK:G
import java.util.List; 8(-N;<Ef2
<Um 5w1
import org.flyware.util.page.Page; #<w2xR]:
R8j\CiV17
/** OK:YnSk "
* @author Joa (%]M a
*/ P`n"E8"ab<
publicclass Result { TI^X gl~
C^
~[b
o
private Page page; AT"!Ys|
U;U19[]
private List content; vPu{xy
<'P+2(Oi
/** }Szs9-Wns
* The default constructor )dRBI)P
*/ @p9YHLxLjQ
public Result(){ \.`{nq
super(); \'P79=AU
} |+aD%'|
^ Mq8jw(2
/** J/A UOInh
* The constructor using fields IU rGJ#}O
* :h<QM$P<
* @param page (0S;eM&
* @param content -+ Mh('K
*/ ' "o2;J)7
public Result(Page page, List content){ q>dERN&
this.page = page; -Rr Qv(
this.content = content; O['5/:-
} [gE2;J0*
0d #jiG
/** bqm%@*fZo
* @return Returns the content. K]Z];C#)
*/ \yA*)X+
publicList getContent(){ d2<+Pp
return content; A!aki}aT~
} kntn9G
690;\O '
/** Gq;!g(
* @return Returns the page. z%[^-l-
*/ {s~t>R p+
public Page getPage(){ JCZ 5q9b
return page; } !RBH(m%
} Q`(.Blgm;
U
jB5Xks
/** 0^zp*u
* @param content iig@$
i#
* The content to set. D=!5l4
*/ ]ZM-c~nL
public void setContent(List content){ h<IPV'1
this.content = content; cR/z; *wr7
} ];au!
_o
.V\:)\<|
/** K6@9=_A
* @param page {qPu}?0
* The page to set. YV/JZc f
*/ gqQ"'SRw
publicvoid setPage(Page page){ " 2J2za
this.page = page; n~G-X
} &{H LYxh
} 5Ak6 q(\
y?yWM8
KPMId`kf
":,J<|Oy
c:sk1I,d~^
2. 编写业务逻辑接口,并实现它(UserManager, /yO|Q{C}M8
dSw%Qv*y
UserManagerImpl) sj\kp
ni
java代码: yUp"%_t0
x4nmDEpa
v\b@;H`
/*Created on 2005-7-15*/ }KCb5_MDF
package com.adt.service; 5>*~1}0T
"fX9bh^
import net.sf.hibernate.HibernateException; <\C/;
I!OV+utF
import org.flyware.util.page.Page; &]mZp&
HHU0Nku@ho
import com.adt.bo.Result; x]%'^7#v)
Yl!~w:O!o
/** xesZ7{ o
* @author Joa a= *qsgPGL
*/ b ?-VZA:
publicinterface UserManager { ,
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Q7vTTn\
public Result listUser(Page page)throws ~gAp`Q
G^Q8B^Lg
HibernateException;
{j{H@rHuy
eub2[,
} jx7b$x]
E,nxv+AQ
SlRQi:
;@R=CQ6
R&`; C<6}D
java代码: wxx3']:
y$7vJl.uS/
NEb M>1>^
/*Created on 2005-7-15*/ &rmXz6F
package com.adt.service.impl; ][IEzeI_LN
#OT8_D
import java.util.List; RMfKM!
vE
X?8 EPCk
import net.sf.hibernate.HibernateException; +KzbaBK
RrG5`2
import org.flyware.util.page.Page; sOY+X
import org.flyware.util.page.PageUtil; 3?+CP-T-j
N#Y|MfLc
import com.adt.bo.Result; =5v=<, ]
import com.adt.dao.UserDAO; Mt93YD-2+
import com.adt.exception.ObjectNotFoundException; mz'r<v2Tc
import com.adt.service.UserManager; %]m/fo4b
,3As
Ng
/** qz@k-Jqq
d
* @author Joa pp2,d`01[L
*/ ,_N+t:*#0
publicclass UserManagerImpl implements UserManager { iW
#|N^
fQkfU;5
private UserDAO userDAO; ]"2;x
XDt MFig
/** K|{IX^3)V
* @param userDAO The userDAO to set. 6`
8H k;
*/ RZgklEU
publicvoid setUserDAO(UserDAO userDAO){ 8nj^x?bn
this.userDAO = userDAO; @F-InfB8.
} JdK'~-L
>STAPrBp+
/* (non-Javadoc) S#{jyU9 ]
* @see com.adt.service.UserManager#listUser Bo#,)%80
,'nd~{pX"(
(org.flyware.util.page.Page) o
_G,Ph!7
*/ GI[TD?s
public Result listUser(Page page)throws 0|J]EsPxu
:]rb} 1nLB
HibernateException, ObjectNotFoundException { UD!-.I]
int totalRecords = userDAO.getUserCount(); xk:=.Qqh
if(totalRecords == 0) -91*VBrOd
throw new ObjectNotFoundException ].Sz2vI
x@)G@'vV|
("userNotExist"); %A$5mi^
page = PageUtil.createPage(page, totalRecords); '-l.2IUyT
List users = userDAO.getUserByPage(page); Ov-Y.+L:
returnnew Result(page, users); s?5vJ:M
Xr
} QhJuH_f 0
J85S'cwZZ
} 81}JX
M/mm2?4
x##0s5Qn
chE}TK
{44#<A<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 gWu<5Y=C
L+X:M/)
询,接下来编写UserDAO的代码: 5<>"d :9
3. UserDAO 和 UserDAOImpl: bk=ee7E7>
java代码: 0sA+5*mdM
fpa~~E-
W8_$]}G8E
/*Created on 2005-7-15*/ Rz#q68
package com.adt.dao; ;EB^1*AEw
5~[m]
import java.util.List; TYKs2+S6
6Vj=SYK
import org.flyware.util.page.Page; g.*DlD%%
Miz?t*|{[
import net.sf.hibernate.HibernateException; WS ^,@>A
]Zz.n5c
/** {SkE`u4Sz
* @author Joa jx{wOb~oO)
*/ b+CJRB1
publicinterface UserDAO extends BaseDAO { =/!RQQ|8o
\iP5.3C
publicList getUserByName(String name)throws U,K=(I7OBX
q5G`q&O5
HibernateException; v`@NwH<r
.b?Aq^i8
publicint getUserCount()throws HibernateException; ?C`r3
63i&<
publicList getUserByPage(Page page)throws 6f:u AFwG
\10KIAQ
HibernateException; wF9L<<&B
[MuZ^'dR
} jV[;e15+
xnfJruT
#W&o]FAA3y
JOz4O
uM\5GK
java代码: osl\j]U8
R nwFxFIQ
n@L@pgo%~
/*Created on 2005-7-15*/ D4\[D8pD
package com.adt.dao.impl; zW\s{
Sn0kJIb
}
import java.util.List; Ze[,0Y!u&
!B92W
import org.flyware.util.page.Page; ah%Ws#&
v[2&0&!K#
import net.sf.hibernate.HibernateException; QWnGolN
import net.sf.hibernate.Query; 1_b*j-j
+4
h!;i
import com.adt.dao.UserDAO; 9;'#,b*(
8ok=&Gq4
/** )o<^6Ic%7
* @author Joa ?%[~J
*/ "X^<g{]
public class UserDAOImpl extends BaseDAOHibernateImpl yIcTc
<=V{tl
implements UserDAO { d]Y;rqjue
WrSc@j&Ycv
/* (non-Javadoc) zPxR=0|
* @see com.adt.dao.UserDAO#getUserByName uorX;yekC
YVwpqOE.=
(java.lang.String) ,l6,k<
*/ YrJUs]A
publicList getUserByName(String name)throws 6Iqy"MQuq
XPU>} 4{
HibernateException { /OWwC%tM/
String querySentence = "FROM user in class p0WUF\"
)
$_1U!z
com.adt.po.User WHERE user.name=:name"; +C8O"
Query query = getSession().createQuery Y X^c}t}U
bY2R/FNL=
(querySentence); FGx)?
query.setParameter("name", name); mf3,V|>[\
return query.list(); DtFHh/X
} X!qK[b@Z
"qNFDr(WM
/* (non-Javadoc) !9WGZfK+0Y
* @see com.adt.dao.UserDAO#getUserCount() 0-S.G38{
*/ V:GypY)
publicint getUserCount()throws HibernateException { [9${4=Kq
int count = 0; N?ccG\t
String querySentence = "SELECT count(*) FROM U8Zb&6
Vf&U`K
user in class com.adt.po.User"; xy7A^7Li
Query query = getSession().createQuery @T~XwJ~
:31_WJ^
(querySentence); )0-A;X2
count = ((Integer)query.iterate().next hHN[K
iR nj N
()).intValue(); &liON1GLM
return count; U-9Aq
} RJ'[m~yl5X
!iKW1ks
/* (non-Javadoc) XnZ$%?$
* @see com.adt.dao.UserDAO#getUserByPage iHGVR
SG)Fk *1
(org.flyware.util.page.Page) ~^1y(-cw
*/ 0[l}@K?
publicList getUserByPage(Page page)throws +PjTT6
<"5l<E
HibernateException { N!(mM;1X)
String querySentence = "FROM user in class f%,S::%Ea
F<,pAxl~@
com.adt.po.User"; dn#I,xa`
Query query = getSession().createQuery KVa{;zBwl
X\h.@+f=
(querySentence); fWmc$r5n](
query.setFirstResult(page.getBeginIndex()) JB~^J5#[Oh
.setMaxResults(page.getEveryPage()); + +}!Gfc?s
return query.list(); [7I bT:ph
} 8OZj24*'DS
O JcS%-~
} /aI@2] |~
yjjq&Cn
.7.lr[$g
.t_t)'L
&s+l/;3
至此,一个完整的分页程序完成。前台的只需要调用 ']1n?K=A
8gP1]xD
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]3O&8,
/*qRbN
的综合体,而传入的参数page对象则可以由前台传入,如果用 Mk}T
y(J~:"}7)
webwork,甚至可以直接在配置文件中指定。 ^/"}_bR
nqo{]fn
下面给出一个webwork调用示例: ='h2z"}\Bn
java代码: NfvPE ]S
!q2zuxq!R
D.a>i?W
/*Created on 2005-6-17*/ Q/S ^-&~
package com.adt.action.user; -{\(s=%
#%"G[B
import java.util.List; Zk=,`sBC
iwK.*07+
import org.apache.commons.logging.Log; <gF]9%2E
import org.apache.commons.logging.LogFactory; m.K cTM%j
import org.flyware.util.page.Page; 9r? Z'~,Za
bTum|GWf
import com.adt.bo.Result; #dZs[R7h
import com.adt.service.UserService; 1C<cwd;9
import com.opensymphony.xwork.Action; CeYhn\m5K0
1B4Qj`:+0
/** h^\vk!Q-d
* @author Joa o]<Z3)
*/ ~!$"J}d}<
publicclass ListUser implementsAction{ X<%D@$
(Mk7"FC7
privatestaticfinal Log logger = LogFactory.getLog '0HOL)cIz
R(wUu#n$
(ListUser.class); "#~>q(4^
E8!`d}\#
private UserService userService; `dZ|Ko%k
} k2Q
private Page page; $:~;U xh=
Zonjk%tC
privateList users; :A zT=^S
sSW'SE?,<
/* wEjinP$2
* (non-Javadoc) +u$l]~St\
* ]DVr-f
~
* @see com.opensymphony.xwork.Action#execute() ?9~^QRLT
*/ 2o SM|
publicString execute()throwsException{ U ]<l-~|
Result result = userService.listUser(page); Lk(ESV;r
page = result.getPage(); T-] {gc
users = result.getContent(); &r1(1<
return SUCCESS; %66="1z0@
} XKWq{,Ks
{+J{t\`
/** ZwUBeyxS=c
* @return Returns the page. Q4u.v,sE
*/ ~IhM(Q*mO!
public Page getPage(){ "Vp
nr +6
return page; Fl`U{03
} iHPsRq!
NxHUOPAJc
/** O*~,L6# }
* @return Returns the users. D;R~!3f./b
*/ 0+CcNY9
publicList getUsers(){ c>LP}PGk
return users; u$d[&|`>_
} Q a (Sb
^\ [p6>
/** n6oOknCna
* @param page +YvF+E
* The page to set. YmC}q20;
*/ z x-[@G
publicvoid setPage(Page page){ cr!8Tp;2A
this.page = page; ^77W#{ Zs
} Qf~>5(,h
]yPK}u
/** Eg)24C R 4
* @param users
e}uK"dl(
* The users to set. vqeH<$WHvy
*/ 0f@+o}i=)
publicvoid setUsers(List users){ bN_e~ z
this.users = users; __g?xw
} g4ZUh@b~
!/p|~K
/** )E.AY
* @param userService _m9k2[N!
* The userService to set. +
+L7*1t
*/ 3=
=["hO
publicvoid setUserService(UserService userService){ TDo)8+.2z
this.userService = userService; _x.2&S89
} `Q*`\-8J
} *ak0(yLn)
|qX?F`
]'pfw9"f~
d_,My lk
{"'M2w:|D1
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, g@'XmT="_
A"7YkOfwH
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 Iy_5k8]
i*|HN"!
么只需要: E 3'I;
java代码: lj]M 1zEz&
8[@,i|kgg0
zLl-{Kk
<?xml version="1.0"?> 5X^\AW
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork OmBM)g
]+e
zg(C}
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 0o8`Y
7u"Q1n(h/
1.0.dtd"> Qb^{`
bVcJ/+Yx|
<xwork> sO) H#G
#f(a,,Uu'
<package name="user" extends="webwork- S5JMt;O
X8tPn_`x
interceptors"> Sv#MlS>
KOg,V_(I
<!-- The default interceptor stack name g}`g>&l5
ILCh1=?{9r
--> ;\th.!'rn
<default-interceptor-ref 46vC/
h_t`)]-
name="myDefaultWebStack"/> `n6cpX5
/'8%=$2Kw
<action name="listUser" iJOoO"Ai
i3XtrP""
class="com.adt.action.user.ListUser"> e_!h>=$%8
<param ~0CNCP
8T"L'{ggWB
name="page.everyPage">10</param> GQg
2!s(
<result ot7f?tF2<J
G9xl-ag+z
name="success">/user/user_list.jsp</result> ->qRGUW
</action> Ip{hg,>
X,3"4 SK
</package> #>_t[9;
();Z,A
</xwork>
C2LG@iCIE
YQ+8lANC
oBmv^=cH
3^Is4H_8
2G|}ENC
&2:WezDF
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 v$` 3}<3-
5<X"+`=9
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。 {B=64,D^7R
`!N.1RP _
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 c-zW
2;|61
FM3.z)>
K4Ed]hX
'n{=`e(}cI
zKk=R6w
我写的一个用于分页的类,用了泛型了,hoho QBmARQ
O|m-[]
java代码: CZy!nR!
Oc~<`C~
Hv"qRuQ?[
package com.intokr.util; 5a6d3u/
;|= 5)KE
import java.util.List; M G&vduu
<qoc)p=__
/** r"L:Mu
* 用于分页的类<br> $XyDw|z[
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ,o2x,I
* R74RJi&
* @version 0.01 SP=8v0
* @author cheng z\k6."e_&
*/ Ng&K5