Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "fL:scq@0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w`UB_h#Bl
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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 .3t[M0sd
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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 ?sdVd
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。 x3MV"hm2
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分页支持类: gV91=Pj
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java代码: O)kC[e4
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package com.javaeye.common.util; )K4 |-<i
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import java.util.List; > 't=r
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publicclass PaginationSupport { 3BDAvdJ4.
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publicfinalstaticint PAGESIZE = 30; hp@giu7
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privateint pageSize = PAGESIZE; tT ~}lW)Y
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privateList items; wyMj^+ 2m
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privateint totalCount; ,)@Q,EHN;
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privateint[] indexes = newint[0]; hCQzD2
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privateint startIndex = 0; BHy#g>KUF
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public PaginationSupport(List items, int `i<;5s!rX
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totalCount){ Ig-9Y;hdmn
setPageSize(PAGESIZE); QU2\gAM
setTotalCount(totalCount); np}F [v
setItems(items); T9osueh4
setStartIndex(0); !=;^Grv>
}
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public PaginationSupport(List items, int (`>RwooE
;H9d.D8
totalCount, int startIndex){ :<YcV#!P
setPageSize(PAGESIZE); @kK${
setTotalCount(totalCount); Yc/Nz(m
setItems(items); k-@CcrepF
setStartIndex(startIndex); TPZZln'3
} /d ?)
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public PaginationSupport(List items, int Vv~rgNh
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totalCount, int pageSize, int startIndex){ {s6;6>-kPW
setPageSize(pageSize); 9[N+x2q
setTotalCount(totalCount); lX/6u
E_%
setItems(items); dq%7A=-
setStartIndex(startIndex); jhr{JApbJv
} u.YPb@
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publicList getItems(){ *z!!zRh3x
return items; m646|G5
} 2-Y%W(bEzs
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publicvoid setItems(List items){ oj /:
this.items = items; 3@kiUbq7Eu
} ]&`_5pS
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publicint getPageSize(){ I8;pMr6
return pageSize; |kyxa2F{
} wrv-"%u)
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publicvoid setPageSize(int pageSize){ :?2+'+%'
this.pageSize = pageSize; n8DWA`[ib
} 9JV(}v5[
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publicint getTotalCount(){ ^} P|L
return totalCount; 2s_shY<=}L
} ;Y5"[C9|
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publicvoid setTotalCount(int totalCount){ 4h\MSTF*
if(totalCount > 0){ 3/+9#
this.totalCount = totalCount; QkBT,c
int count = totalCount /
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pageSize; p&ytUTna
if(totalCount % pageSize > 0) n|dLK.Q
count++; W|_
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indexes = newint[count]; H)(@A W+-
for(int i = 0; i < count; i++){ P/5bNK!
indexes = pageSize * FVNxjMm,
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i; Y[k%<f
} 4vq,W_n.hQ
}else{ vi')-1Y
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this.totalCount = 0; w'oP{=y[
} ) E.KB6
} 6*u#^">,<
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publicint[] getIndexes(){ uF_gfjR[m
return indexes; 'L4@|c~x
} 9`yG[OA
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publicvoid setIndexes(int[] indexes){ t$^1A1Ef
this.indexes = indexes; Z[<rz6%cB
} ,rVm81-2
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publicint getStartIndex(){ r\Nf309~
return startIndex; !7"-9n
} O3WhO@`6)
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publicvoid setStartIndex(int startIndex){ :SUPGaUJ"
if(totalCount <= 0) 0Po",\^
this.startIndex = 0; 4vKp341B
elseif(startIndex >= totalCount) Bh$hgf.C
this.startIndex = indexes -Zc
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R L7OFfMe
[indexes.length - 1]; p!BZTwP
elseif(startIndex < 0) cf)2GoV>e
this.startIndex = 0; 0(\ybppx
else{ NPc]/n?vDj
this.startIndex = indexes L)H'g
-L>xVF-|:1
[startIndex / pageSize]; "W$,dWF
} fx(^}e
} =$;i
NPy{ =#k4
publicint getNextIndex(){ y33+^
int nextIndex = getStartIndex() + RO?5WJpPj
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pageSize; 3qU#Rg
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if(nextIndex >= totalCount) q'~?azg:
return getStartIndex(); Fw? ;Y%
else Q= IA|rN
return nextIndex; 8##-fv]
} 1Y!"C
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publicint getPreviousIndex(){ }mQ7N&cC
int previousIndex = getStartIndex() - ]ZKmf}A)1P
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pageSize; t:NTk(
if(previousIndex < 0) vn<z\wVbf
return0; }la\?I
else m`CcU`s
return previousIndex; 4UD<g+|
} :#W40rUb
}z:g}".4
} )\#w=P
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抽象业务类 ?Iy$'am]L
java代码: _ #]uk&5a
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/** lj0"2@z3"E
* Created on 2005-7-12 6p`AdDV
*/ [mX/]31
package com.javaeye.common.business; }9yAYZ0q{b
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import java.io.Serializable; Lt>"R! "x
import java.util.List; d\&{Ev9v
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import org.hibernate.Criteria; `F5iZWW1
import org.hibernate.HibernateException; .U|irDO
import org.hibernate.Session; nI4Kuz`dF
import org.hibernate.criterion.DetachedCriteria; R!IODXP=
import org.hibernate.criterion.Projections; ??eSGQ|
import "`]G>,r_
) *Mr{`
org.springframework.orm.hibernate3.HibernateCallback; +k|t[N
import JW[y
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org.springframework.orm.hibernate3.support.HibernateDaoS :L gFd
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upport; z%-Yz-G9
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import com.javaeye.common.util.PaginationSupport; 5|S|S))_Q
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public abstract class AbstractManager extends L1=+x^WQ
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HibernateDaoSupport { BUT{ }2+K
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privateboolean cacheQueries = false;
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privateString queryCacheRegion; d,kh6'g2@
9}p>='
publicvoid setCacheQueries(boolean .?{rd3[ec
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cacheQueries){ ^uB9EP*P
this.cacheQueries = cacheQueries; ?m.WqNBH7
} S9/oBxGN
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publicvoid setQueryCacheRegion(String cojtQD6
(T;4'c
queryCacheRegion){ ?/ xk
this.queryCacheRegion = gzfs9e
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queryCacheRegion; hTgWqp
} PwP;+R};|
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publicvoid save(finalObject entity){ A&EVzmj-+X
getHibernateTemplate().save(entity); Cm@e^l!
} DM
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publicvoid persist(finalObject entity){ ~ [L4,q
getHibernateTemplate().save(entity); l&3f<e
} NIZN}DnP
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publicvoid update(finalObject entity){ h^_Sd"l3
getHibernateTemplate().update(entity); ~2
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} `4^-@}
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publicvoid delete(finalObject entity){ _<tWy+.
getHibernateTemplate().delete(entity); :|cC7,S
} X(sHFVU+
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publicObject load(finalClass entity,
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finalSerializable id){ _,*ld#'s
return getHibernateTemplate().load W/03L, 1
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(entity, id); 9G njJ
} hP1}Do
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publicObject get(finalClass entity, pxm{?eBz
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finalSerializable id){ -L%J,f[&,
return getHibernateTemplate().get 1, 5"sQ$
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(entity, id); YrlOvXW
} "^sh:{
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publicList findAll(finalClass entity){ <dzfD;
return getHibernateTemplate().find("from CeL`T:]r
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" + entity.getName()); Ik{[BRzUgt
} ;. jnRPo";
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publicList findByNamedQuery(finalString VVY#g%(K
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namedQuery){ >K]s)VuWR
return getHibernateTemplate 'Xj9sAB
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().findByNamedQuery(namedQuery); <{$0mUn;s|
} M0Eq
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publicList findByNamedQuery(finalString query, !~X[qT
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finalObject parameter){ >`\f,yql6
return getHibernateTemplate ahezDDR-.i
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().findByNamedQuery(query, parameter); 5R^e
} )ro3yq4??
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publicList findByNamedQuery(finalString query, o}EipTL
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finalObject[] parameters){ "9mVBa|Q
return getHibernateTemplate DeqTr:
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().findByNamedQuery(query, parameters); +7yirp~`K
} y2"PKBK\_
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publicList find(finalString query){ :exgdm;N
return getHibernateTemplate().find c?@WNv
+rT%C&ze
(query); 82w;}(!
} lr>:S
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publicList find(finalString query, finalObject wUUDq?!k\
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parameter){ )C?bb$
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return getHibernateTemplate().find VD=}GY33=
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(query, parameter); R$[nYw
} XwI~ 0
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public PaginationSupport findPageByCriteria . X(^E
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(final DetachedCriteria detachedCriteria){ Cxn<#Kf\-<
return findPageByCriteria FG-v71!h#
q_0So}
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;3\oU$'
} YH_mWN\Wu
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public PaginationSupport findPageByCriteria aT9+]
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(final DetachedCriteria detachedCriteria, finalint ^]x%z*6
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startIndex){ i}fAjS:W
return findPageByCriteria t r)[6o#
*$U+
(detachedCriteria, PaginationSupport.PAGESIZE, 87QK&S\
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startIndex); _(#HQd,i
} <K^{36h
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public PaginationSupport findPageByCriteria $0uh8RB
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(final DetachedCriteria detachedCriteria, finalint Uavr>-
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pageSize, GM1z@i\5
finalint startIndex){ }}R?pU_
return(PaginationSupport) IJWUNKqo=
H2f!c{t$p
getHibernateTemplate().execute(new HibernateCallback(){ =[N=mC
publicObject doInHibernate P}YtT3.K
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(Session session)throws HibernateException { 2#<)-Cak
Criteria criteria = kTC'`xv
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detachedCriteria.getExecutableCriteria(session); 4rcNBmA,
int totalCount = bOEO2v'cQ
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((Integer) criteria.setProjection(Projections.rowCount kAu-=X
5=;LHS*
()).uniqueResult()).intValue(); vbo|q[z
criteria.setProjection 3YKJN4
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(null); ~}lYp^~:J
List items = ,M4G_U[
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criteria.setFirstResult(startIndex).setMaxResults -<g&U*/E
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(pageSize).list(); n!Dr:$
PaginationSupport ps = OouIV3
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new PaginationSupport(items, totalCount, pageSize, jOkc'
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startIndex); fbTq?4&Q
return ps; &:>3tFQSH
} \?$`dA [
}, true); (6y[,lYH
} Fjs:rZ#{
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public List findAllByCriteria(final Z<yLu'48)A
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DetachedCriteria detachedCriteria){ xj ?#]GR
return(List) getHibernateTemplate ^"\3dfzKM
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().execute(new HibernateCallback(){ Qkvg85
publicObject doInHibernate J]!&E~Y
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(Session session)throws HibernateException { 2bs={p$}a
Criteria criteria = 3jI
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9}[UZN6
detachedCriteria.getExecutableCriteria(session); Q.U
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return criteria.list(); VRb+-T7"
} J1s~w`,
}, true); Jbv[Ql#
} ]+"25V'L
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public int getCountByCriteria(final !J6;F}Pd/
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DetachedCriteria detachedCriteria){ [%uj+?}6O
Integer count = (Integer) A_y]6~Mu?~
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getHibernateTemplate().execute(new HibernateCallback(){ $_ BoG
publicObject doInHibernate ~6Xr^An/Z
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(Session session)throws HibernateException { qxQuXF>:#
Criteria criteria = <Jf[N=
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detachedCriteria.getExecutableCriteria(session); TQ,KPf$0U
return |zkZF|-
)bgaqca_{
criteria.setProjection(Projections.rowCount .c5)`
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()).uniqueResult(); baO'FyCs9&
} 9cnLf#
}, true); yrF"`/zv6|
return count.intValue(); SSAf<44e
} LmZ"_
} Y'{F^VxA/
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用户在web层构造查询条件detachedCriteria,和可选的 }eK.\_t=
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1iJa j
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PaginationSupport的实例ps。 ?;YymD_
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ps.getItems()得到已分页好的结果集 JW}O`H9
ps.getIndexes()得到分页索引的数组 +V `*
ps.getTotalCount()得到总结果数 l+UUv]:1
ps.getStartIndex()当前分页索引 T&q0TBT
ps.getNextIndex()下一页索引 \3WQ<t)W
ps.getPreviousIndex()上一页索引 Wb%t6N?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 EY^+ N>
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 rizWaw5E!8
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一下代码重构了。 Fd;%wWY.zm
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我把原本我的做法也提供出来供大家讨论吧: U~GQ JR
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首先,为了实现分页查询,我封装了一个Page类: VK>Cf>
java代码: (Zoopkxw
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/*Created on 2005-4-14*/ KL\hV .6
package org.flyware.util.page; d` X1cG
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/** He)!Ez\X
* @author Joa _Q9I
W
* z=6zc-$y 9
*/ !T"jvDYH
publicclass Page { {fI"p;|
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/** imply if the page has previous page */ ae>B0#=
privateboolean hasPrePage; IBz)3gj J
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/** imply if the page has next page */ F#)@ c
privateboolean hasNextPage; E}g)q;0v|2
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/** the number of every page */ _KJ!C!
privateint everyPage; n+57# pS7
NHQi_U
/** the total page number */
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privateint totalPage; tUk)S
b!JrdJO,DP
/** the number of current page */ dT7!+)s5-
privateint currentPage; ;R([w4[~
3_ ZlZ_Tq
/** the begin index of the records by the current [tk6Kx8a
M.9w_bW]#D
query */ WRp0.
privateint beginIndex; dUH+7.\
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/** The default constructor */ |@BX*r
public Page(){ [=TD)o>W(p
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} 7d^ ~.F
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/** construct the page by everyPage @y2cC6+'t
* @param everyPage oc"7|YG
* */ \DcO.`L
public Page(int everyPage){ J,*+Ak
~
this.everyPage = everyPage; hrW2#v
} 8 .t3`FGH
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/** The whole constructor */ <~zPt&C]V
public Page(boolean hasPrePage, boolean hasNextPage, :n,x?bM
?|Ey WAL
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int everyPage, int totalPage, j@R"AP}
int currentPage, int beginIndex){ * .g[vCy
this.hasPrePage = hasPrePage; @a i2A|
this.hasNextPage = hasNextPage; 9y*2AaxW
this.everyPage = everyPage; t 7D~JAx6
this.totalPage = totalPage; { u3giB
this.currentPage = currentPage; $ZkT G
this.beginIndex = beginIndex; |RL\2j|
} ,W BKN)%u
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/** EE-wi@
* @return phR:=Ox|1
* Returns the beginIndex. ,uPN\`.u8
*/ >P ~j@Lv
publicint getBeginIndex(){ P)O:lYX
return beginIndex; ^Rh}[
} *!9=?
L=dQ,yA
/** %c@PTpAM
* @param beginIndex *j<{3$6Ii
* The beginIndex to set. ?}U?Q7vx@@
*/ w:ASB>,!
publicvoid setBeginIndex(int beginIndex){ ZgfhNI\
this.beginIndex = beginIndex; Z*'<9l_1
} |G/U%?`
C]&/k_k
/** ?)H:.]7-x
* @return Sd/7#
* Returns the currentPage. vxS4YR b
*/ V
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publicint getCurrentPage(){ urg^>n4V]
return currentPage; *M.,Yoj
} .{-X1tJ7
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/** V\AY =u
* @param currentPage 3WM*4
* The currentPage to set. 1amEQ
*/ ~UHjc0
publicvoid setCurrentPage(int currentPage){ = |E8z
u%
this.currentPage = currentPage; \,#;gS"
} BIEq(/-
5,+fM6^V
/** `FwE^_9d
* @return AH?[K,3
* Returns the everyPage. KquuM ]5S
*/ .Rt~d^D@
publicint getEveryPage(){ ix"BLn]YZ
return everyPage; #pyFIUr=w
} RL[F 9g
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/** v\E6N2.S
* @param everyPage #/5eQTBD
* The everyPage to set. vdigw.=z
*/ ZYt1V"2VJ
publicvoid setEveryPage(int everyPage){ ;ik,6_/Y
this.everyPage = everyPage; WcY $=\7
} NKc<nYdK?
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/** -hq^';,
* @return 7yjun|Lt}X
* Returns the hasNextPage. I>q!co9n
*/ H^dw=kS
publicboolean getHasNextPage(){ J #5V>7G
return hasNextPage; "MK2QIo
} $)~ :H-
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wd
/** ]^8CtgC
* @param hasNextPage {-Gh 62hDg
* The hasNextPage to set. &DjA?0`J
*/ bk&kZI.D
publicvoid setHasNextPage(boolean hasNextPage){ #=)!\
this.hasNextPage = hasNextPage; dc0&*/`:
} ^rd%{6m
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/** RI+Y+z
* @return .IM]B4m
* Returns the hasPrePage. AxeQv'e
*/ 6"NtVfui
publicboolean getHasPrePage(){ X(BX+)YR
return hasPrePage; M!i*DU+SE
} *sau['Ha
i6$HwRZm#
/** L2_[M'
* @param hasPrePage Q}cti/
* The hasPrePage to set. B_D0yhh
*/ zeq")A
publicvoid setHasPrePage(boolean hasPrePage){ @n=&muC}
this.hasPrePage = hasPrePage; zhbSiw
} S}cR+d1}h
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/** SurreD<x
* @return Returns the totalPage. ?:&2iW7z
* @^DVA}*b)
*/ e"*1l>g
publicint getTotalPage(){ $:# :"
return totalPage; w~:F?
} i8p$wf"aW
m#R"~ >
/** Qv
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* @param totalPage |ICn/r~
* The totalPage to set. L8H:,} 2
*/ 1wH6 hN,
publicvoid setTotalPage(int totalPage){ ^>>9?
this.totalPage = totalPage; ,F*HZBNFZ
} O jNOvh&N
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} eo@8?>}{X
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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 {p$@)b
m9\"B3sr
个PageUtil,负责对Page对象进行构造: X
@pm !c#
java代码: ExN$J
4q:8<*W=
Jt#HbAY
/*Created on 2005-4-14*/ KhP_U{)D
package org.flyware.util.page; U&{w:P
8aC=k@YE
import org.apache.commons.logging.Log; _n!>*A!
import org.apache.commons.logging.LogFactory; Kv9FqrDj
Lb?q5_
/** )q.ZzijG/
* @author Joa 8 R7w$3pp\
* , s otZT
*/ 7h0u7 N
publicclass PageUtil { q@~{g[
^Sj;~
privatestaticfinal Log logger = LogFactory.getLog 7+}WU 4
[8q`~S%-]
(PageUtil.class); XT*/aa-1'
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/** D(TG)X?
* Use the origin page to create a new page N{ $?u
* @param page p|NY.N
* @param totalRecords nP<u.{q
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* @return <L11s%5-
*/ /hmDePo}
publicstatic Page createPage(Page page, int ~-y&C%
{0np
totalRecords){ |(2#KMEWa
return createPage(page.getEveryPage(), b:r8r}49
_cC1u7U9
page.getCurrentPage(), totalRecords); 10.ZBfn
} rNKeY48\
_~{J."q
/** P;-.\VRu
* the basic page utils not including exception
2VUN
r%WHYhD
handler Oo-4WqRJ
* @param everyPage m/jyc#
L:u
* @param currentPage %'=2Jy6h
* @param totalRecords "KS"[i!3j
* @return page 7'65+c[&
*/ gmn b
publicstatic Page createPage(int everyPage, int evD=]iVD
#_`p
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currentPage, int totalRecords){ ^$C&{%
everyPage = getEveryPage(everyPage); :VWN/m
currentPage = getCurrentPage(currentPage); |(TEG.<g
int beginIndex = getBeginIndex(everyPage, Y2'HP)tfIw
rBU)@I pDG
currentPage); .qKfhHJ
int totalPage = getTotalPage(everyPage, o8H\l\(
98| v.d
totalRecords); FGie*t
boolean hasNextPage = hasNextPage(currentPage, >R_m@$`
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totalPage); 6d6Dk>(V
boolean hasPrePage = hasPrePage(currentPage); US^%pd
$T:;KcW)
returnnew Page(hasPrePage, hasNextPage, <P ?gP1_zi
everyPage, totalPage, kOdpW
currentPage, kP/<S<h,g
Y2tBFeWY
beginIndex); !4gHv4v;
} n[r1h=?j3
ujN~l_4
privatestaticint getEveryPage(int everyPage){ {dP6fr1z
return everyPage == 0 ? 10 : everyPage; $)c[FR~a
} MxI*ml8z?
5Ma."?rW
privatestaticint getCurrentPage(int currentPage){ o0F,!}
return currentPage == 0 ? 1 : currentPage; KHx;r@{<
} O"kb*//
ZR0 OqSp]
privatestaticint getBeginIndex(int everyPage, int 'vu]b#l3
ZZwIB3sNhf
currentPage){ zBwqIJfM
return(currentPage - 1) * everyPage; u|.|dv'mbp
} :xq{\"r
"VHT5k
privatestaticint getTotalPage(int everyPage, int ~`^kP.()
BB9eQ:
xO
totalRecords){ $cuBd
int totalPage = 0; #`U?,>2q
\CE+P5
if(totalRecords % everyPage == 0) R.l!KIq
totalPage = totalRecords / everyPage; 0%;| B
else UWhHzLcXh
totalPage = totalRecords / everyPage + 1 ; !FyO5`v
PX0N7L
return totalPage; 1:-
M<=J?f
} oOLA&N-A~
,3eN&
privatestaticboolean hasPrePage(int currentPage){ }.U(Gxu$
return currentPage == 1 ? false : true; OC-d5P
} wu11)HFL|z
uOKD#
privatestaticboolean hasNextPage(int currentPage, bG* l_
?/5<}W#7}
int totalPage){ xluAjOQ6
return currentPage == totalPage || totalPage == hVT>HER
f\=,_AQ
0 ? false : true; ZAeJTCCk
} ]9'F<T= $_
v0(}"0
VKu_l
} <0hVDk~
K4E2W9h
#lSGH 5Fp?
>ifys)wg>
zVe,HKF/
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。 "}%j'
$sb@*K}:4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 H8B.c%_|U
p[%~d$JUq
做法如下: dD'KP4Io@
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 n ~ &ssFC
wv\"(e7(
的信息,和一个结果集List: r4gLoHD)
java代码: nygeR|:\
vl}}h%BC
53pfo:1'
/*Created on 2005-6-13*/ Xs"d+dc
package com.adt.bo; tQyQ+1
WLh!L='{BK
import java.util.List;
mI:D
k\/es1jOEh
import org.flyware.util.page.Page; Dp#27Yzc
t1oTZ
/** FEopNDy@y
* @author Joa NU{eoqaT
*/ 0pB'^Q{
publicclass Result { P@n
rcgM.
\k6OP
private Page page; < 0S\P=\
'u%_Ab_H
private List content; iWUxB28
e$Y7V
/** RLLL=?W@
* The default constructor tpeMq-
*/ n[v`F
public Result(){ JlE+CAny
super(); FOPmvlA\-<
} H.l
WHM+H4
Po\+zZjo
/** 8(A
k
* The constructor using fields w)YTHY(k;
* &?y|Pn
* @param page |\"%Dy[m
* @param content ww%4MHPp8
*/ QZO<'q`L
public Result(Page page, List content){ +:c}LCI9<
this.page = page; yd45y}uS;F
this.content = content; U}=H1f,
} M3GFKWQI,`
6/(Z*L"~6k
/** <3=k
* @return Returns the content. JE$$6X
*/ LA6Ik_-F
publicList getContent(){ ~+RrL,t#
return content; *_Pkb.3R
} jlUT9Zp
s <$*A;t
/** qe0ZM-C_
* @return Returns the page. cyL|.2,
*/ oK"#*n
public Page getPage(){ Av/y
return page; [f$pq5f='
} &mA{_|>
#X5Tt ;
/** N$ 2Iz
* @param content vDc&m
* The content to set. [{ A5BE -
*/ IY2f$YV
public void setContent(List content){ 5hAs/i9_
this.content = content; tf9a- s
} 9w\C
vO&R
MSt@yKq
/** Z$)jPDSr
* @param page B|;?#okx
* The page to set. 4%TmW/yd
*/ 0J=
$ A
publicvoid setPage(Page page){ BT5~MYBl
this.page = page; kh>i#9Ie
} '}P$hP_d
} ]U 1S?p
+gb"}
cN
&23t/`
O0mQHpi:
AAc2u^spx
2. 编写业务逻辑接口,并实现它(UserManager, +2s][^-KV
z}7U>y6`
UserManagerImpl) E `%*lGu_
java代码: P$`k*
v
&=.7-iC|W
+j6^g*
/*Created on 2005-7-15*/ s!
sG)AR.J
package com.adt.service; j2%#xZ{33
mi sPJO&QD
import net.sf.hibernate.HibernateException; v #Q(g/^
B :1r;8{j
import org.flyware.util.page.Page; \&Oc}]
]#$rTWMl'
import com.adt.bo.Result; 0Jm)2@
"LVN:|!
/** +n<;);h
* @author Joa 45Q#6BtE
*/ 2|8$@*-\
publicinterface UserManager { kjR-p=}
hB]<li)"C
public Result listUser(Page page)throws Ng1[y4R}
X.ZY1vO
HibernateException; O'W[/\A56M
2fdC @V
} 0av2w5>af
z8w@pT
7!8R)m^1[
xa%2w]
mDIN%/S'
java代码: =$vy_UN
RsP^T:M}$
95 X6V
/*Created on 2005-7-15*/ KWT[b?
package com.adt.service.impl; DGx<Nys@B
"& q])3h =
import java.util.List; 3#c0p790
t3aDDu
import net.sf.hibernate.HibernateException; L>2gx$f
4:XVu
import org.flyware.util.page.Page; aw'o=/a8
import org.flyware.util.page.PageUtil; bRc~e@
[Z+E_Lbz
import com.adt.bo.Result; (0bXsfe
import com.adt.dao.UserDAO; @LDu08lr
import com.adt.exception.ObjectNotFoundException; }F)eA1
import com.adt.service.UserManager; ~^"s.Lsb
+ WFa4NZ
/** @)S d3xw[
* @author Joa *
n>YS
*/ |K$EULzz
publicclass UserManagerImpl implements UserManager { ] Y6y ]u
'xc=N
private UserDAO userDAO; o7s<G8;?
UL\gcZ
Zkl
/** Vb8{OD3PK
* @param userDAO The userDAO to set. :.NCS`z_
*/ hc5iIJ]
publicvoid setUserDAO(UserDAO userDAO){ AU
H_~SY
this.userDAO = userDAO; H-Or
} EN2/3~syO-
UNKXfe(X9
/* (non-Javadoc) CK RnkTTiV
* @see com.adt.service.UserManager#listUser F%e5j9X`
uze5u\
(org.flyware.util.page.Page) Je;HAhL
*/ g2&P
public Result listUser(Page page)throws CjlA"_!%E
ao)8ie
HibernateException, ObjectNotFoundException { E@^mlUf
int totalRecords = userDAO.getUserCount(); 4>I;^LHn
if(totalRecords == 0) D,;6$Pvg^
throw new ObjectNotFoundException G_n~1?
}h`ddo
("userNotExist"); bjGQ04da
page = PageUtil.createPage(page, totalRecords); 1
gx(L*y,
List users = userDAO.getUserByPage(page); {'eF;!!Dy
returnnew Result(page, users); ]5i]2r1
} (e6KSRh2fF
_'DZoOH|VE
} Hqm1[G)
BpZ17"\z
@k,}>Tk
A**PGy.Ni
I=Xj;\b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 d7Devs
k
=OF]xpI'&a
询,接下来编写UserDAO的代码: D<XRu4^;
3. UserDAO 和 UserDAOImpl: y5lhmbl: e
java代码: !7fVO2m T
9Kd:7@U
*%`jcF
/*Created on 2005-7-15*/ Hs6}~d
package com.adt.dao; B#;0{
/ :@X<
import java.util.List; Luu.p<
Z:s:NvFX
import org.flyware.util.page.Page; Pi:=0,"XOp
0}y-DCuQ
import net.sf.hibernate.HibernateException; |F^h>^
x
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/** >^hy@m
* @author Joa h|t\rV^
*/
-z$&lP]
publicinterface UserDAO extends BaseDAO { #^oF^!
@Tg +Kt
publicList getUserByName(String name)throws eMV@er|
8|iMD1
HibernateException; X mX
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publicint getUserCount()throws HibernateException; [E/}-m6g
4Gm (P~N
publicList getUserByPage(Page page)throws $*i"rlJC
gR:21*&cz
HibernateException; |Zrkk>GW:
0ge^pO\Z
} d8Kxtg
Y
=C.WM*= '
=3Hv
5.e.
BT
9K`uGu
java代码: !~~j&+hK\
v<U +&D{
M~&X?/8
/*Created on 2005-7-15*/ nzK"eNDN.
package com.adt.dao.impl; 3?R QPP
'U'#_mYG
import java.util.List; wam-=3W
86,$ I+
import org.flyware.util.page.Page; -P3;7_}]:h
,dIo\Lm
import net.sf.hibernate.HibernateException; "G`8>1tO_
import net.sf.hibernate.Query; Z w&_Wt
y3vm+tJc{
import com.adt.dao.UserDAO; ^9C9[$Q
\v}3j^Yu
/** 19t'
* @author Joa Yi+~}YP.E(
*/ ep3iI77/
public class UserDAOImpl extends BaseDAOHibernateImpl /4Lmu+G4
{Qla4U
implements UserDAO { #Qp.O@e
E@F:U*A6%
/* (non-Javadoc) xz$S5tgDQK
* @see com.adt.dao.UserDAO#getUserByName @0>3))
/Aq):T T
(java.lang.String) {?dW-
*/ b|HH9\
publicList getUserByName(String name)throws TGJ\f
zUhJr$N$
HibernateException { ?~5J!|r#
String querySentence = "FROM user in class Xqac$%[3
S(f V ,;Z
com.adt.po.User WHERE user.name=:name"; 8?7gyp!k_f
Query query = getSession().createQuery :>t?^r(
]'/ZSy,
(querySentence); ~t~5ctJ@
query.setParameter("name", name); mrfc.{`[
return query.list(); >%D=#}8l@
} _Vq7Gxy$R
~?c}=XL-
/* (non-Javadoc) wCb%{iowH
* @see com.adt.dao.UserDAO#getUserCount() <C'S#5,2
*/ Ay Obaa5
publicint getUserCount()throws HibernateException { 3[jk}2R';p
int count = 0; ^:RDu q
String querySentence = "SELECT count(*) FROM Nh[{B{k
ymsqJ
user in class com.adt.po.User"; Mwdw7MZ"S
Query query = getSession().createQuery 69v[*InSd
]cv|A^
(querySentence); 0+\~^
count = ((Integer)query.iterate().next ?Ze3t5Ll
",ic"
~
()).intValue(); Nv
iPrp>c
return count; ZREAEGi{
} (qP !x 2j
0P_Y6w+
/* (non-Javadoc) QJG]z'c+
* @see com.adt.dao.UserDAO#getUserByPage 63$ R')
2ju1<t,8)
(org.flyware.util.page.Page) }fo?K|Xx
*/ 79^on8 k}
publicList getUserByPage(Page page)throws A_t<SG5
O;A/(lPW+
HibernateException { ]rh)AE!Y(
String querySentence = "FROM user in class "iof -b=ys
8bX\^&N
com.adt.po.User"; \?} {wh8
Query query = getSession().createQuery &\C{,:[
rr[9sk`^H
(querySentence); rwxJR@Ttn
query.setFirstResult(page.getBeginIndex()) fuH Dif,
.setMaxResults(page.getEveryPage()); XKsG2>l-W
return query.list(); .~5cNu'#m
} K6,5C0
Mdh(Mp(w
} _OF8D
uREc9z`Q'
~P5!VNJ;r
Ej1 [ry
VmTk4?V4
至此,一个完整的分页程序完成。前台的只需要调用 |jV4]7Luq
dBG]J18
userManager.listUser(page)即可得到一个Page对象和结果集对象 'Ph4(Yg
EMH?z2iGd
的综合体,而传入的参数page对象则可以由前台传入,如果用 `.dTkL
^}8_tZs8\
webwork,甚至可以直接在配置文件中指定。 f (
`.q
)^!-Aj\x
下面给出一个webwork调用示例: U[S;5xeF.j
java代码: ^;YD3EZw
i[ BR"(
2|~&x~
/*Created on 2005-6-17*/ 5b B[o6+
package com.adt.action.user; -o#0Yt}3
>?e*;f$VdJ
import java.util.List; e_ 6
i896
JoZC+G
import org.apache.commons.logging.Log;
xuelo0h,
import org.apache.commons.logging.LogFactory; "0L@cOyG
import org.flyware.util.page.Page; /]xd[^
j.CC.[$g
import com.adt.bo.Result; YA^9, q6u?
import com.adt.service.UserService; N13 <!QQ
import com.opensymphony.xwork.Action; CWkm\=
No[xf9>t
/** &F#X0h/m=
* @author Joa bi^LpyEn
*/ i6m;2 UAa
publicclass ListUser implementsAction{ U(./LrM05
kX1hcAa
privatestaticfinal Log logger = LogFactory.getLog zMrZ[AU
Zt` ,DM
(ListUser.class); xs &vgel>
,75,~
private UserService userService; ij hMJ?3
{/7'uD\
H
private Page page; v;K\#uc_
JmYi&
privateList users; "E2
g7n&
.
~|^du<X
/* 0t4i'??
* (non-Javadoc) F"23>3
* v!`M=0k
* @see com.opensymphony.xwork.Action#execute() YgWnPp
*/ "Pys3=h
publicString execute()throwsException{ "Ln\ZYB]
Result result = userService.listUser(page); C1G Wi4)
page = result.getPage(); SwP h-6
users = result.getContent(); b'-gy0
return SUCCESS; 5?vIkf
} j#p3c
G#%
=R`k/
/** 56':U29.]
* @return Returns the page. Nq~bO_-I
*/ oW+R:2I~O
public Page getPage(){ Dkdm~~Rr
return page; E0oJ|My
} ^$#Q_Y|
ac&tpvij
/** !E7/:t4
* @return Returns the users. o`sn/x
*/ d7G'+B 1
publicList getUsers(){ rz.`$b
return users; N]=.I
} uPp(l4(+
ohh 1DsB
/** v^E5'M[A
* @param page oL6_Ya
* The page to set. 3> fuH'=
*/ ja>T nfu
publicvoid setPage(Page page){ [D?E\Nkk
this.page = page; er<~dqZ}]
} (Pu*[STTT
G/`_$ c
/** XnG!T$
* @param users k<f*ns
* The users to set. i/Hi
*/ (^Ln|3iz
publicvoid setUsers(List users){ -zTeIvcy5
this.users = users; )t.q[O`
} >ab=LDoM
:D/R
/** #e0+;kBh
* @param userService jf2E{48P
* The userService to set. 3~S~)quwP
*/ O0I/^
publicvoid setUserService(UserService userService){ F%|(pHk
this.userService = userService; kR_[p._
} PRUGUHY
} C eg6o&^
u@|yw)
# \M<6n{
EagI)W!s[
Fq3;7Cq=hD
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, bVrvb`0
d8K^`k+x
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
)Ob{]
1GNAx\(
么只需要: SVHtv0Nx
java代码: a&<<X:$Hy
s6
^JgdW
&,)tD62s
<?xml version="1.0"?> :H87x?e[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork := 8vy
RU'J!-w{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- HvngjP{>
f;Dz(~hw
1.0.dtd"> XU54skN
<*\J 6:^n
<xwork> 8;5/_BwMu
{F4:
<package name="user" extends="webwork-
g$97"d'
5-J-Tn
interceptors"> ~+g5?y
5SjS~9
<!-- The default interceptor stack name M1i|qjb:l
Psv!`K
--> "&ks83
<default-interceptor-ref 3_ >R's8P
i>~?XVU
name="myDefaultWebStack"/> Ob6vg^#
wVVe L$28
<action name="listUser" K$Ph$P@
g,;MV7yE
class="com.adt.action.user.ListUser"> F,
"x~C
<param cQR1v-Xt
+EB##
name="page.everyPage">10</param> bODl
q
<result uu:)jx i
Dn[1BWM/7
name="success">/user/user_list.jsp</result> `4=b|N+b"
</action> $1v5*E
(X9V-4
</package> 40<&0nn
u%pief
</xwork> 8%4`Yj=
EI;\of2,
t'J
fiGM
bm4W,
g U?)
*t_&im%E
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 =6sXZ"_Tw
s:ruCS
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。 J-}NFWR;t
?Z=v&d[o)
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 VC.?]'OqD
qEAF!iB]L
5-OvPTY`M
HZ}*o%O
gY9"!IVe+
我写的一个用于分页的类,用了泛型了,hoho l;.BlHyu
/K^cU;E,
java代码: (Y>MsqwWfC
xR:h^S^W ~
ueR42J%s
package com.intokr.util; .bE,Q9:
?@1'WD t
import java.util.List; p[b\x_0%c
ZYA(Bg^
/** +RkYW*|$S
* 用于分页的类<br> D}T,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> "" U_|JH-
* {9Y'v
* @version 0.01 `9ox?|iJ
* @author cheng )hug<D *h
*/ #*!$!c{
public class Paginator<E> { OLrD4 e
privateint count = 0; // 总记录数 9zJ`;1
privateint p = 1; // 页编号 %\l,X{X
privateint num = 20; // 每页的记录数 W%1S:2+Kl
privateList<E> results = null; // 结果 }>0
Kc=
~S3eatM$9
/** \ax%I)3
* 结果总数 }kj6hnQ
*/ L|X5Ru
publicint getCount(){ ^NDX4d;
return count; Nj0)/)<r+
} aJ8pJ{,P
rg,63r
publicvoid setCount(int count){ vNC0M:p,
this.count = count; f[b YjIX
} T Rw6$CR
Aq!['G
/** C~qhwwh
* 本结果所在的页码,从1开始 {0 ~0
* c*dww
* @return Returns the pageNo. 9#<Og>t2y
*/ 5-^%\?,x
publicint getP(){ 8-:k@W
return p; zc+;VtP|8
} >A&@W p1
F-^HN%
/** `VtwKt*
* if(p<=0) p=1 <+gl"lG
* ` a>vPW
* @param p l,.?-|Poa
*/ ozC!q)j
publicvoid setP(int p){ ]ufW61W6Ci
if(p <= 0) bSf(DSqx
p = 1; Zjg\jo
this.p = p; "ILWIzf.]
} @@IA35'tc
{yR)}r
/** Wq(l :W'
* 每页记录数量 R`2A-c
*/ L]d@D0.Z
publicint getNum(){ /\rq$W_
return num; <(4#4=ivP
} ,SF.@^o@a
Eap/7U1Q
/** y.p6%E_`
* if(num<1) num=1 fm%RNAPvc
*/ 7Zt\G-QV
publicvoid setNum(int num){ gvNZrp>e!
if(num < 1) -j_I_
num = 1; :(>9u.>l?5
this.num = num; -l H>8+
} | ",[C3Jg
xGfDz*t
/** 87KrSZ
* 获得总页数 c^O#O
*/ z,FTsR$x
publicint getPageNum(){ _I_?k+#WFe
return(count - 1) / num + 1; 1~DD9z
} 1G%PXrEj8
l&*)r;9
/** \bm6/fhA:
* 获得本页的开始编号,为 (p-1)*num+1 tvT8UW'
*/ Q)`gPX3F
publicint getStart(){ =nx:GT3&[
return(p - 1) * num + 1; -'[(Uzj
} Wi[m`#
-I-Uh{)j
/** *3O >J"
* @return Returns the results. zN+*R;Ds
*/ =kh>s$We
publicList<E> getResults(){ >:E*7
return results; pXh~#o6V
} K\+}q{
.^lbLN^2
public void setResults(List<E> results){ ie@`S&.8 T
this.results = results; x
XM!E
8
} e j%;%`C-
^Wfgwmh
public String toString(){ {R-82% X
StringBuilder buff = new StringBuilder vX0"S
8ts+'65|F
(); !I5~))E
buff.append("{"); RP,:[}mPl
buff.append("count:").append(count); $i:||L^8p
buff.append(",p:").append(p); u'i%~(:$\)
buff.append(",nump:").append(num); LkGf|yd_
buff.append(",results:").append s!ZW'`4!z
z8/xGQn
(results); pp]_/46nN
buff.append("}");
{kPe#n>xT
return buff.toString(); q{cp|#m#G
} 3z)"U
LxlbD#<V
} 7~"(+f
J+b!6t}mZn
KO"Jg-6r|