Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5T;M,w6DV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D<$~bUkxR
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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 i"%X[(U7
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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
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分页支持类: g\&[;v
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java代码: ?)x>GB(9ZN
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package com.javaeye.common.util; lk{
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import java.util.List; ]Mi
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publicclass PaginationSupport { Z^,C><Yt
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publicfinalstaticint PAGESIZE = 30; i rMZLc6
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privateint pageSize = PAGESIZE; `O(ec
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privateList items; Etty{r}
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privateint totalCount; Mk"+*G
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privateint[] indexes = newint[0]; 5R}Qp<D[^
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privateint startIndex = 0; LY2oBX@fC
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public PaginationSupport(List items, int q}e"E
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totalCount){ <qN0Q7
setPageSize(PAGESIZE); EZaWEW
setTotalCount(totalCount); /kE3V`es
setItems(items); 9@
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setStartIndex(0); 9K~2!<
} Ql
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public PaginationSupport(List items, int 3}=r.\]U
:S}!i?n
totalCount, int startIndex){ ~C=I{qzF+
setPageSize(PAGESIZE); 1C\OL!@L
setTotalCount(totalCount); D_
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setItems(items); lxy_O0n
setStartIndex(startIndex); |t*(]U2O0
} t
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public PaginationSupport(List items, int /
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totalCount, int pageSize, int startIndex){ cjt<&b*
setPageSize(pageSize); \#.,@g
setTotalCount(totalCount); x@I*(I
setItems(items); <l]P
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setStartIndex(startIndex); py.lGywb_
} q65KxOf`
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publicList getItems(){ l
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return items; \O5`R-
} |m7U^
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publicvoid setItems(List items){ gRv5l3k
this.items = items; #j
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} P'f
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publicint getPageSize(){ {'VP_ZS1v
return pageSize; r(xh5{^x
} ,gGIkl&
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publicvoid setPageSize(int pageSize){ cHOtMPyQ
this.pageSize = pageSize; MTo<COp($
} nmZz`P9g
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publicint getTotalCount(){ "V-k_d "
return totalCount; vN:gu\^-
} 8uq^Q4SU
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publicvoid setTotalCount(int totalCount){ k8H@0p
if(totalCount > 0){ {Vw+~8
this.totalCount = totalCount; d4KTwn5g
int count = totalCount / I Wcgh`8
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pageSize; ,T@+QXh
if(totalCount % pageSize > 0) i^Vb42 %y
count++; IvGQ7
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indexes = newint[count]; "s!!\/^9C
for(int i = 0; i < count; i++){ 0+MNu8t
indexes = pageSize * twElLOE
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} $U%M]_
}else{ Z-|.j^n
this.totalCount = 0; |S.G#za
} Oxs O
} }a?PBo`
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publicint[] getIndexes(){ ~_opU(;f
return indexes; aX`"V/
} +v.uP [H
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publicvoid setIndexes(int[] indexes){ @_s`@,=
this.indexes = indexes; Ie{98
} Qt` hUyL
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publicint getStartIndex(){ ]&6# {I-
return startIndex; HS> (y2}'
} !/]F.0
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publicvoid setStartIndex(int startIndex){ K~'!JP8@
if(totalCount <= 0) x|4m*>Ke
this.startIndex = 0; F5UvD[i
elseif(startIndex >= totalCount) ?>c*[>LpZ
this.startIndex = indexes 6.
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[indexes.length - 1]; YXCltME
elseif(startIndex < 0) np2oXg%
this.startIndex = 0; e RY2.!
else{ aT}Mn(F*?
this.startIndex = indexes ?;84 M@
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[startIndex / pageSize]; R_9 &V!fl
} S(NH# ^
} t8X$M;$
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publicint getNextIndex(){ 6v8HR}iK
int nextIndex = getStartIndex() + yg({g
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pageSize; HYVSi3[
if(nextIndex >= totalCount) MKVz'-`u
return getStartIndex(); tGt/=~n9
else hojP3 [
return nextIndex; ]xGo[:k|E
} 5ncjv@Aa
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publicint getPreviousIndex(){ s18o,Zs'
int previousIndex = getStartIndex() - lGrp^
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pageSize; |;xm-AM4r
if(previousIndex < 0) A/5??3H
return0; ZEY="pf
else TljN!nv]
return previousIndex; *u
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} #I>
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} cr GFU?8
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抽象业务类 xPBSJhla
java代码: A:|dY^,:?*
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/** zED#+-7
* Created on 2005-7-12 U'(Exr[
*/ L{`S^'P<
package com.javaeye.common.business; 5mzOr4*0
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import java.io.Serializable; =BD} +(3
import java.util.List; %=p:\+`VI
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import org.hibernate.Criteria; BR&T,x/d
import org.hibernate.HibernateException; EY3x o-H
import org.hibernate.Session; 'I$-h<W
import org.hibernate.criterion.DetachedCriteria; 8:#\g
import org.hibernate.criterion.Projections; SZUhZIz&
import 0e./yPTT
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org.springframework.orm.hibernate3.HibernateCallback;
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import 05sWN 0
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org.springframework.orm.hibernate3.support.HibernateDaoS 1XfH,6\8i
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upport; Yz<,`w5/6~
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import com.javaeye.common.util.PaginationSupport; nP]tc
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public abstract class AbstractManager extends IZ){xI
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HibernateDaoSupport { !LGnh
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privateboolean cacheQueries = false; s|40v@M
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privateString queryCacheRegion; Wp2W:JX:
@|I:A
publicvoid setCacheQueries(boolean R$>]7-N}
@ P:b\WCI
cacheQueries){ IE;Fu67wi
this.cacheQueries = cacheQueries; l>(w]
} 48}L!m @
cb36 ~{
publicvoid setQueryCacheRegion(String ZD$W>'m{F
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queryCacheRegion){ ! z!lQ~
this.queryCacheRegion = euxkw]`h6
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queryCacheRegion; Qu 7#^%=
} )gX7qQ
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publicvoid save(finalObject entity){ 4}i2j
getHibernateTemplate().save(entity); SW94(4qo
} O
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publicvoid persist(finalObject entity){ ,(1n(FZ
getHibernateTemplate().save(entity); wEQ7=Gyx
} B: '}SA{
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publicvoid update(finalObject entity){ "o| f
getHibernateTemplate().update(entity); |)%]MK$;
} I
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publicvoid delete(finalObject entity){ M lv
getHibernateTemplate().delete(entity); /mdPYV
} tVAWc$3T
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publicObject load(finalClass entity, ]1 V,_^D
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finalSerializable id){ WO}l&Q
return getHibernateTemplate().load 8Ce|Q8<8]
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(entity, id); KC"#
} _oV;Y`_
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publicObject get(finalClass entity, 7g* "AEk
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finalSerializable id){ Ffvv8x
return getHibernateTemplate().get 8vk*",
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(entity, id); mYU7b8x_
} v?BVUH>#9
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publicList findAll(finalClass entity){ 4t C-msTf
return getHibernateTemplate().find("from A-=B#U F
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" + entity.getName()); ] "ZL<?3g
} .o27uB.
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publicList findByNamedQuery(finalString |"K<
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namedQuery){ gY\g+df-
return getHibernateTemplate yN'<iTh
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().findByNamedQuery(namedQuery); ZWtlO P#]
} /w!!jj^
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publicList findByNamedQuery(finalString query, bqo+b{i\
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finalObject parameter){ [N35.O6P6u
return getHibernateTemplate 5s5GBJ?
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().findByNamedQuery(query, parameter); X0QY:?
} "8.to=Lx
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publicList findByNamedQuery(finalString query, /~8<;N>,+
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finalObject[] parameters){ ^~p^N <
return getHibernateTemplate {6y@;Fd
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().findByNamedQuery(query, parameters); 3Y;<Q>roT
} 9_$i.@L1
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publicList find(finalString query){ yLC5S3^1\"
return getHibernateTemplate().find &J]|pf3m
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(query); eX{:&Do
} B4&K2;fg_
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publicList find(finalString query, finalObject _`oP*g =
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parameter){ >}uDQwX8
return getHibernateTemplate().find *y}<7R
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(query, parameter); p)x*uqSd
} =7e|e6
4 !q4WQ ;
public PaginationSupport findPageByCriteria ?cZ#0U
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(final DetachedCriteria detachedCriteria){ 5W Z9z-6
return findPageByCriteria nDFF,ge;a#
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -(Zi
} #4yh-D"
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public PaginationSupport findPageByCriteria (t.OqgY
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(final DetachedCriteria detachedCriteria, finalint i[+cNJ|$B0
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startIndex){ #"T< mM7
return findPageByCriteria >~%EB?8
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(detachedCriteria, PaginationSupport.PAGESIZE, 1#Ls4+]5
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startIndex); 7])cu>/
} rnkq.
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public PaginationSupport findPageByCriteria 7A@iu*t
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(final DetachedCriteria detachedCriteria, finalint odPdWV,&*
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pageSize, WGK:XfOBQ
finalint startIndex){ tM%
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return(PaginationSupport) u@@0YUa
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getHibernateTemplate().execute(new HibernateCallback(){ G1!yPQa7d
publicObject doInHibernate 34Fc
oud);
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(Session session)throws HibernateException { eZck$]P(6H
Criteria criteria = 76} a
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detachedCriteria.getExecutableCriteria(session); z5>
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int totalCount = +=N!37+G
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((Integer) criteria.setProjection(Projections.rowCount 5PRS|R7
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()).uniqueResult()).intValue(); 7GFE5>H
criteria.setProjection Jc3Z1 Tt
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(null); d3IMQ_k
List items = 2_i9
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criteria.setFirstResult(startIndex).setMaxResults yu~o9
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(pageSize).list(); O'WBO"
PaginationSupport ps = y8!#G-d5
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new PaginationSupport(items, totalCount, pageSize, {,9^k'9
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startIndex); y-1!@|l0:6
return ps; iPuX
} ]zt77'J
}, true); K<g<xW* X
} Ofm?`SE*|
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public List findAllByCriteria(final >QcIrq%=
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DetachedCriteria detachedCriteria){ Qm >x?
return(List) getHibernateTemplate =.Hq]l6+
$oo`]R_
().execute(new HibernateCallback(){ d41DcgG'j(
publicObject doInHibernate m4r!Ck|
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(Session session)throws HibernateException { 2C&G'@>
Criteria criteria = AWG;G+
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detachedCriteria.getExecutableCriteria(session); O^L#(8bC
return criteria.list(); jMAZ4M
} sx]kH$
}, true); ?nwFc3qw
} 5.TeH@(
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public int getCountByCriteria(final C@ns`Eh8w
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DetachedCriteria detachedCriteria){ ~Q3y3,x
Integer count = (Integer) V9 J`LQ\0
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getHibernateTemplate().execute(new HibernateCallback(){ *?o`90HHP[
publicObject doInHibernate c?/R=/H
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(Session session)throws HibernateException { !4 =]@eFk
Criteria criteria = pVa9g)+z}
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detachedCriteria.getExecutableCriteria(session); ]}za
return JK/VIu&!
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criteria.setProjection(Projections.rowCount *%#Sa~iPo
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()).uniqueResult(); q-lejVS(g
} 6`JY:~V"
}, true); Ob~7r*q
return count.intValue(); bZKlQ<sI
} 6]D%|R,Q#}
} Y;uQq-C P
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用户在web层构造查询条件detachedCriteria,和可选的 vhz[ H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~0T;T
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PaginationSupport的实例ps。 mV'XH
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ps.getItems()得到已分页好的结果集 Jjr&+Q^3Tu
ps.getIndexes()得到分页索引的数组 ,'%wadOo
ps.getTotalCount()得到总结果数 m,X8Cy|vQ
ps.getStartIndex()当前分页索引 KccI Yn~
ps.getNextIndex()下一页索引 e,cSB!7
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [(kC/W)!
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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 2vLV1v$,q
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一下代码重构了。 S!@h\3d8{
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我把原本我的做法也提供出来供大家讨论吧: /qwl;_Jcf
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首先,为了实现分页查询,我封装了一个Page类: eJ"je@vvrK
java代码: W3M1> (
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/*Created on 2005-4-14*/ ->S# `"@$
package org.flyware.util.page; w40 -K5wt>
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/** \ y}!yrQ
* @author Joa _+*+,Vx
* O}Mu_edM
*/ 5z=.Z\M`8
publicclass Page { :+?w>
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/** imply if the page has previous page */ Ss$/Bh>hN
privateboolean hasPrePage; M7PGs-l
D~T;z pS
/** imply if the page has next page */ l6~wm1vO
privateboolean hasNextPage; _rakTo8BY
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/** the number of every page */ ;Im%L=q9GL
privateint everyPage; E},^,65
h( V:-D
/** the total page number */ 3I.0jA#T&/
privateint totalPage; <oKoz0!
8ZN"-]*
/** the number of current page */ oQL$X3S
privateint currentPage; s.IYPH|pn
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/** the begin index of the records by the current WFm\ bZ.
=#so[Pd
query */ SsBiCctn
privateint beginIndex; F[5sFkM7
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dc=}c/6x
/** The default constructor */ x;@wtd*QB
public Page(){ Ej#pM.
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} 'i;/?'!W6
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/** construct the page by everyPage #O,;3S
* @param everyPage s,|"s|P
* */ Tg yY 9
public Page(int everyPage){ KSgYf;
this.everyPage = everyPage; (`)ZR%i
} S-2@:E
vhE^jS<Tg
/** The whole constructor */ M$$Lsb [
public Page(boolean hasPrePage, boolean hasNextPage, (CR]96n
kD\7wz,ui
h#~\-j9>
int everyPage, int totalPage, Qk[YF
int currentPage, int beginIndex){ 08MY=PC~R
this.hasPrePage = hasPrePage; (,XbxDfM
this.hasNextPage = hasNextPage; VBq|j"o0"
this.everyPage = everyPage; g5@P
this.totalPage = totalPage; kesuM3
this.currentPage = currentPage; #gc v])to
this.beginIndex = beginIndex; 2kkqPBc_
} k}hTSL
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/** 7wz9x8 \t
* @return _L%
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* Returns the beginIndex. pZ)N,O3
*/ FByA4VxB
publicint getBeginIndex(){
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return beginIndex; iPCDxDLN3V
} K:L_y1!T
5MHcgzyp
/** #D ]P3
* @param beginIndex ^|UD&6 dx
* The beginIndex to set. KbGz3O'u
*/ :>K8oE
publicvoid setBeginIndex(int beginIndex){ t->I# t7
this.beginIndex = beginIndex; :ZsAWe{%,J
} sL4j@Lt
60--6n
/** yN{TcX
* @return Csf!I@}Z
* Returns the currentPage. M97MIku~9
*/ vX}#wDNP
publicint getCurrentPage(){ <^(>o
return currentPage; T8NDS7&?
} aL^
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/** xU;/LJ6
* @param currentPage (Tv~$\=
* The currentPage to set. @bF4'M
*/
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publicvoid setCurrentPage(int currentPage){ ^^T
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this.currentPage = currentPage; RMs+pN<5
} Ny5$IIFe
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/** /2>.*H_2
* @return NnRX 0]
* Returns the everyPage. &a!MT^anA~
*/ !X4m6gRaP
publicint getEveryPage(){ S1a6uE
return everyPage; SsCV}[
} ?+G
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@iBaJ"*,
/** 2*5pjd{Kt
* @param everyPage o@[oI\Vr!
* The everyPage to set. vw6DHN)k
*/ \rM5@
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publicvoid setEveryPage(int everyPage){ ows3%
this.everyPage = everyPage; +}x\|O
} O39f
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/** fL~@v-l#~
* @return !g4u<7
* Returns the hasNextPage. ymb{rKkN3
*/ *h
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publicboolean getHasNextPage(){ _)ZxD--Qg
return hasNextPage; ;T :]?5W!
} pEq }b+-
4 u=v
/** 2= zw!
* @param hasNextPage ,t
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* The hasNextPage to set. gX]ewbPDQ
*/ |ITh2m
publicvoid setHasNextPage(boolean hasNextPage){ f~:wI9
this.hasNextPage = hasNextPage; c2wgJH!g
} `+!F#.
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/** -"6Z@8=
* @return ^@f.~4P*I
* Returns the hasPrePage. heScIe
N^`
*/ p^)w$UL}}
publicboolean getHasPrePage(){ LRqlK\
return hasPrePage; j8W<iy
} 0M!GoqaA
m,)o&ix1
/** uxlrJ1~M
* @param hasPrePage v}TFM
* The hasPrePage to set. {gb` %J
*/ CU@}{}Yl
publicvoid setHasPrePage(boolean hasPrePage){ dWP<,Z>
this.hasPrePage = hasPrePage; R$bDj>8
} SBg|V
m4?a'z"
/** qIwsK\^p
* @return Returns the totalPage. 4q\&Mb3
* 3fxcH
*/ I ZBY*kr
publicint getTotalPage(){ Y+{jG(rg.F
return totalPage; NUFW
SL>
} _&N}.y)+t
dP?QPky{9
/** $"ACg!=M
* @param totalPage ;tC$O~X
* The totalPage to set. V[0
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*/ &qP0-x)
publicvoid setTotalPage(int totalPage){ bnZ H
this.totalPage = totalPage; nP_)PDTFp
} ART0o7B
t==\D?Rt
} y@r g_Paq
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8^67,I-c
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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 ]CDUHz
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个PageUtil,负责对Page对象进行构造: CU:HTz=
java代码: g3f;JB
QUDpAW
NAOCQDk{
/*Created on 2005-4-14*/ MlR]+]
package org.flyware.util.page; -vv_6ZL[
0:JNkXZ:
import org.apache.commons.logging.Log; QCO,f
import org.apache.commons.logging.LogFactory; {E0\mZ2
w?Pex]i{
/** uU=!e&3
* @author Joa mbns%%GJU
* Tj+U:#!!~
*/ S]NT +XM
publicclass PageUtil { =#vJqA
_9'hmej
privatestaticfinal Log logger = LogFactory.getLog 7^syu;DT9Y
t N4-<6
(PageUtil.class); / ;+Mz*
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/** R_b4S%jhx
* Use the origin page to create a new page b!r%4Ah
* @param page qkqtPbQ 7
* @param totalRecords c
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* @return `g<0FQA
*/ w
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publicstatic Page createPage(Page page, int b,X+*hRt
\VWgF)_
totalRecords){ 7Ah
return createPage(page.getEveryPage(), LTB
rg[X
Bg}l$?S
page.getCurrentPage(), totalRecords); BkP4.XRI
} ;*0nPhBw0>
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/** %cBOi_}}~
* the basic page utils not including exception iNc!zA4
N6`U)=2o>h
handler iCCe8nK
* @param everyPage -/2B fIq
* @param currentPage @$iZ9x6t
* @param totalRecords =
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* @return page 4o"?QV:
*/ 0f@9y
publicstatic Page createPage(int everyPage, int 6)BPDfU,
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currentPage, int totalRecords){ T2_iH=u
everyPage = getEveryPage(everyPage); ?#Y:2LqP C
currentPage = getCurrentPage(currentPage); R x( yn
int beginIndex = getBeginIndex(everyPage, ;G[0%z+*
;WAa4r>
currentPage); ,.h@tN<C
int totalPage = getTotalPage(everyPage, EwmNgmYq
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totalRecords); }9glr]=
boolean hasNextPage = hasNextPage(currentPage, jGT|Xo>t
jT!?lqr(Rb
totalPage); %hlgLM
boolean hasPrePage = hasPrePage(currentPage); sVGQSJJ5
y0-UO+;
returnnew Page(hasPrePage, hasNextPage, }Q@~_3,UJ
everyPage, totalPage, "n)AlAV@
currentPage, =:!>0~
__zHe-.m
beginIndex); 9C=*>I27?
} _#MKp H
/DP0K
@%
privatestaticint getEveryPage(int everyPage){ 8_o~0lb
return everyPage == 0 ? 10 : everyPage; |5ge4,}0
} 3rd8mh&l
EJRkFn8XG'
privatestaticint getCurrentPage(int currentPage){ Ke=+D'=
return currentPage == 0 ? 1 : currentPage; 6kMkFZ}+
} aGfp"NtL
D[}^G5
privatestaticint getBeginIndex(int everyPage, int 9|[uie
,7k-LAA
currentPage){ e6bh,BwgQq
return(currentPage - 1) * everyPage; OhMJt&s9P=
} Z`86YYGK
{jH'W)nR
privatestaticint getTotalPage(int everyPage, int H?!DcUg CC
Pf<yLT]
totalRecords){ =9W\;xE S
int totalPage = 0; bC~I}^i\
KU*aJl_n,
if(totalRecords % everyPage == 0) $4~Z]-38#A
totalPage = totalRecords / everyPage; GNEPb?+T
else 9_,f)2)~W
totalPage = totalRecords / everyPage + 1 ; bM5o-U#^ C
0FY-e~xr
return totalPage; KV$4}{
} A_WaRYG
;E[Q/
tr:w
privatestaticboolean hasPrePage(int currentPage){ ,hT.Ok={36
return currentPage == 1 ? false : true; RjTGm=1w
} eO(U):C2
Hb::;[bm:
privatestaticboolean hasNextPage(int currentPage, ^6R(K'E}
|$e'yx6j
int totalPage){ =6O*AJ
return currentPage == totalPage || totalPage == [p~,;%
s;=C&N5g
0 ? false : true; s@5~HyeI
} ?FjnG_Uz`D
y Vm>Pj6
h3&|yS|
} Mp>(cs
EApbaS}Up
5ya^k{`+ZO
vp.?$(L^@/
{V[}#Mf
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 J|DZi2o
-W<1BJE
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 S4[#[w`=
_ZFEo< `'
做法如下: o kA<
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %D8.uGsh
3+s$K(% I
的信息,和一个结果集List: pMy:h
java代码: "y&`,s5}
.UNV &R0
!U>WAD9
/*Created on 2005-6-13*/ vNrn]v=|}7
package com.adt.bo; Z
b$]9(RS
Qubu;[0+a
import java.util.List; 6]d]0TW_
qP<D9k>
import org.flyware.util.page.Page; X<Z(,B
3X1 1Gl
/** R3l{.{3p2
* @author Joa zxCx2.7
*/ $7c,<=
publicclass Result { 3\Q 9>>
/e?0Iv"
8>
private Page page; dt,Z^z+"E
d[J_iD{ &
private List content; ^r(My}
D9A%8[Yo
/** jVQ89vf
~
* The default constructor RR
^7/-
*/ DyiJ4m}kh
public Result(){ `o295eiY(b
super(); la_c:#ho
} C !Srv7
\3^ue0
/** 1ONkmVtL
* The constructor using fields gCC7L(1
* t(-,mw
* @param page zU+q03l8Ur
* @param content '!8-/nlv1
*/ 2M'dTXz
public Result(Page page, List content){ *wj5( B<y
this.page = page; 16~E
this.content = content; z]+L=+,,
} rf:H$\yw
HOFxOBV
/** kDWEgnXK,v
* @return Returns the content. 7#%Pry
*/ ,&WwADZ-s
publicList getContent(){ =urGs`\
return content; 4}v|^_x-i
} bIyg7X)/
\rzMgR$/rj
/** (BeJ,K7
* @return Returns the page. 6`@J=Q?
*/ #o4tG
public Page getPage(){
Pap6JR{7
return page; 2a48(~<_
} U|%}B(
+jwHYfAK)
/** `w\P- q
* @param content 9yC22C:
* The content to set. tOLcnWt
*/ tMX$8W0
c
public void setContent(List content){ 62qjU<Z
this.content = content; A8Q^y
AP^
} {#k[-\|;
CL4N/[UM
/** 8Ejb/W_
* @param page *1<kYrB
* The page to set. iI";m0Ny
*/ Gw$ 5<%sB
publicvoid setPage(Page page){ ~<n.5q%Z
this.page = page; )B0%"0?`8
} >!xyA;
} /0XMQy
Tgr,1)T
uoI7'
:Nv
+lqGf
ji1vLu4|t
2. 编写业务逻辑接口,并实现它(UserManager, 0zB[seyE
"O4A&PJD
UserManagerImpl)
r9})~>
java代码: 5P-t{<]tx
([dd)QU
X$ZVY2
/*Created on 2005-7-15*/ A!B.+p[G
package com.adt.service; 4v hz`1
u6ULk<<\
import net.sf.hibernate.HibernateException; ()?83Xj[c
LsuOmB| ^
import org.flyware.util.page.Page; (jDz[b#OPz
}r5yAE
import com.adt.bo.Result; MkPQ@so
KddCR&
/** PVBz~rG
* @author Joa ~E7IU<B
*/ =,#--1R7g
publicinterface UserManager { d/&>
`[i
I1U2wD
public Result listUser(Page page)throws w&aZ 97{
}Pg}"fb^
HibernateException; m"iA#3l*=
:]@c%~~!&
} I'BhN#GhX
S-7&$n
_Ns EeKU
K8sRan[4}
_V-K yK
java代码: p/HDG
^T:u
2H)4}5H
o'!=x$Ky
/*Created on 2005-7-15*/ P.,U>m
package com.adt.service.impl; 6p)AQTh>
Q,&Li+u|
import java.util.List; *7jz(iX
0B]q /G(
import net.sf.hibernate.HibernateException; +y?Ilkk;j
W8^m-B&
import org.flyware.util.page.Page; zl|z4j'Irc
import org.flyware.util.page.PageUtil; yijP
ro{!X, _$,
import com.adt.bo.Result; 4V')FGB$
import com.adt.dao.UserDAO; Dp
](?Yr
import com.adt.exception.ObjectNotFoundException; j )6
import com.adt.service.UserManager; tbd=A]B-
tTLg;YjN
/** 05`"U#`:
* @author Joa |h\7Q1,1~2
*/ &Vz$0{d5
publicclass UserManagerImpl implements UserManager { 3S:Lce'f
:hX[8u
private UserDAO userDAO; >CqzC8JF
E[]5Od5#
/** 9Rnypzds
* @param userDAO The userDAO to set. }aVZ\PDg
*/ 3 !@
publicvoid setUserDAO(UserDAO userDAO){ "d_wu#fO)
this.userDAO = userDAO; YNEwX$)M,B
} JNfL
jfE)<
?BnU0R_r]
/* (non-Javadoc) cQU;PH]
* @see com.adt.service.UserManager#listUser -Z"4W
"+F'WCJ-(*
(org.flyware.util.page.Page) y>P+"Z.K%}
*/ $oK&k}Q
public Result listUser(Page page)throws *|fF;-#v
+(3_V$|Dv
HibernateException, ObjectNotFoundException { ::|~tLFu
int totalRecords = userDAO.getUserCount(); qz-QVY,
if(totalRecords == 0) 2X?GEO]/4
throw new ObjectNotFoundException KUAzJ[>
TN2Ln?[xU
("userNotExist"); j~Aq-8R=
page = PageUtil.createPage(page, totalRecords); kOYUxr.b
List users = userDAO.getUserByPage(page); 4+RR`I8$Ge
returnnew Result(page, users); @%]A,\
} 4I$Y(E}
AI-*5[w#A
} *VZ|Idp
hH8&g%{2
$F2Uv\7=
dZU#lg
iVXt@[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lK0ny>RB
[0 F~e
询,接下来编写UserDAO的代码: $.SBW=^V
3. UserDAO 和 UserDAOImpl: \#{PV\x:Nn
java代码: *;Jb=
/T w{JO#Q
6_Fr \H
/*Created on 2005-7-15*/
P8tdT3*6/
package com.adt.dao; :
uncOd.
g^'h4qOa
import java.util.List; ,&P
4%N"
VfX^iG r
import org.flyware.util.page.Page; ->sxz/L
~dYCY_a
import net.sf.hibernate.HibernateException; e8F]m`{_"
Y2u\~.;oq
/** CL=%eSsuD
* @author Joa C0wtMD:G
*/ #S}orWj
publicinterface UserDAO extends BaseDAO { B>,eHXW
>t+U`6xK
publicList getUserByName(String name)throws
=@HS
/eF@a!
HibernateException; S
/hx\TzC
;M:AcQZ|_
publicint getUserCount()throws HibernateException; UVo`jb|>
o
aSzI5J]/=
publicList getUserByPage(Page page)throws `q^#u
V(MYReaPC]
HibernateException; f[@96p?a[
DXs an
} :<QknU}dwy
d*@T30
e97G]XLR
<xI<^r'C9e
U"PcNQy
java代码: (2g
a:}K
;8s L
f9.?+.^_
/*Created on 2005-7-15*/ hyI7X7Hy
package com.adt.dao.impl; 77P\:xc
<J/ =$u/
import java.util.List; ma.84~m
J]F&4O
import org.flyware.util.page.Page; m{\
&
k
uzYB`H<
import net.sf.hibernate.HibernateException; *_(X$qfoW
import net.sf.hibernate.Query; Nu5|tf9%A
%5o2I_Cjz
import com.adt.dao.UserDAO; )l3Uf&v^f
dljE.peL
/** ARKM[]
* @author Joa NXW*{b
*/ u,^CFws_
public class UserDAOImpl extends BaseDAOHibernateImpl l2D*b93
bJ~H
implements UserDAO { DB'v7
Ij0
st-{xC#N#
/* (non-Javadoc) 8Q'Emw |
* @see com.adt.dao.UserDAO#getUserByName $%bSRvA
l/.{F ;3F
(java.lang.String) 5\ mRH
*/ uYh!04u
publicList getUserByName(String name)throws 02;jeZ#z
/0s1;?
HibernateException { 3$|/7(M&DA
String querySentence = "FROM user in class Pvxb6\G&d
-`O{iHfM|P
com.adt.po.User WHERE user.name=:name"; f1 ;
Query query = getSession().createQuery VD;*UkapZx
m'o dVZ7
(querySentence); .wfydu)3
query.setParameter("name", name); SE'Im
return query.list(); d:=' Xs
} t R^f]+Up
LrB
0x>
/* (non-Javadoc) x~5uc$
* @see com.adt.dao.UserDAO#getUserCount() R~vGaxZ$
*/ d$t"Vp
publicint getUserCount()throws HibernateException { Q:}]-lJg
int count = 0; MpV<E0CmE
String querySentence = "SELECT count(*) FROM /bo}I-<2
Z)?$ZI@
user in class com.adt.po.User"; <kh.fu@.Q
Query query = getSession().createQuery -F 5BJk
honh'j
(querySentence); $0])%
count = ((Integer)query.iterate().next 6u[fCGi%
3I6ocj[,
()).intValue(); }vndt*F
return count; (b&g4$!x&5
} #:K=zV\
8Fn\ycX#"l
/* (non-Javadoc) tsXKhS;/w
* @see com.adt.dao.UserDAO#getUserByPage +
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zl0{lV
(org.flyware.util.page.Page) Ak'=l;
*/ _imuyt".+
publicList getUserByPage(Page page)throws c%H' jB[
K~W(ZmB
HibernateException { EVmBLH-a
String querySentence = "FROM user in class 6^`iuC5
X\^nV
com.adt.po.User"; [doEArwn
Query query = getSession().createQuery s68(jYC7[
dlu*s(O"
(querySentence); ?qh-#,O9B
query.setFirstResult(page.getBeginIndex()) "{q#)N
.setMaxResults(page.getEveryPage()); #{i*9'
return query.list(); waMF~#PJlt
} }7 N6nZj`
= Xgo}g1
} "Q?+T:D8|
HDe\Oty_
CPz<iU
?ZF):}rvZ
Ailq,c
至此,一个完整的分页程序完成。前台的只需要调用 6v`3/o
GZ%vFje_
K
userManager.listUser(page)即可得到一个Page对象和结果集对象 HC iRk1
V_7\VKR
的综合体,而传入的参数page对象则可以由前台传入,如果用 P9v(5Z00|d
mLCDN1UO{
webwork,甚至可以直接在配置文件中指定。 }b_Ob
#QNN;&L]R
下面给出一个webwork调用示例: AA\a#\#Z3
java代码: dN8Mfa)
Q}BMvR 9w
z^bS+0S5x!
/*Created on 2005-6-17*/ VAPeMO
ck
package com.adt.action.user; U]PB)
">V1II
7
import java.util.List; >|f"EK}m!
l\<.*6r
import org.apache.commons.logging.Log; fO<40!%9cQ
import org.apache.commons.logging.LogFactory; gOF^?M11x
import org.flyware.util.page.Page; rN0<y4)!
A3]A5s6
import com.adt.bo.Result; zdN[Uc+1Bd
import com.adt.service.UserService; b:==:d:0s
import com.opensymphony.xwork.Action; z.Cj%N
o'2eSm0H
/** PK|-2R"M
* @author Joa 35\ |#2qw6
*/ W+h2 rv
publicclass ListUser implementsAction{ <-VBb[M#
s.J4&2Q
privatestaticfinal Log logger = LogFactory.getLog c^}y9% 4c
80lei
(ListUser.class); '*J+mZt N
BJ|l
private UserService userService; fU>l:BzJK
6bm 7^e(
private Page page; ,#Z%0NLe
[LoQYDku
privateList users; HP# SR';E
o1AbB?%=
/* l=DF)#>w
* (non-Javadoc) AtQ.H-8r
* $*q|}Tvl#
* @see com.opensymphony.xwork.Action#execute() :ld~9
*/ { 'b;lA]0
publicString execute()throwsException{ 5m8u :6kQu
Result result = userService.listUser(page); )/RG-L
page = result.getPage(); 4'QX1p
users = result.getContent(); -^_2{i
return SUCCESS; /7}pReUj
} "i0>>@NR'
CsZ~LQ=DB
/** s6H.Q$3L
* @return Returns the page. a?[[F{X9^
*/ Iz0$T.T
public Page getPage(){ 8(1*,CJQg
return page; sfF ~k-
} ~I||"$R
@KQ>DBWQM
/** '1mk;%
* @return Returns the users. $|K:
9
*/ juF9:Eah
publicList getUsers(){ \.L jA_
return users; "J(M. Y
} J!:BCjRdw
wf8{v
/** YBt=8`r
* @param page J(]|)?x2
* The page to set. kL8rqv^
*/ 9c@M(U@Yh
publicvoid setPage(Page page){ w;'XqpP$*|
this.page = page; ~?\U];l
} q?!HzZ
uu6 JZp
/** |
0
* @param users }UPC~kC+Z
* The users to set. t^01@ejM+
*/ 3](hMk,}
publicvoid setUsers(List users){ /.]u%;%r[
this.users = users;
2%@tnk|@
} ajSB3}PN
M@[W"f
Wq
/** 6KddHyFz
* @param userService Ci`o;KVj
* The userService to set. DNGyEC
*/ O#)1zD}
publicvoid setUserService(UserService userService){ ,L& yKS@
this.userService = userService; KA2>[x2
} 8pnD6Lp>
} *w0!C:mL&
+[76 _EXy
]IV{;{E)
x}/jh
C.?^] Y
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, n]g"H
$8\u
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 "xlR>M6e
H_&to3b(
么只需要: MG?,,8s O
java代码: m)A:w.o
;@Zuet
<$s6?6P
<?xml version="1.0"?> 5]&sXs
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }O\IF}X
i:s=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _r:Fmn_%-
ad}8~6}_&
1.0.dtd"> )U~|QdZ
MT!Y!*-5
<xwork> cN@_5
J4+K)gWB
<package name="user" extends="webwork- 7Fj8Mp|
-,yp?<
interceptors"> >6S7#)0T
|enLv12Gm
<!-- The default interceptor stack name r D@*xMW
Z5t^D|
--> r^5%0_F]
<default-interceptor-ref &g;!n&d zP
p_I^7 $
name="myDefaultWebStack"/> $b`nV4p
b-ss^UL
<action name="listUser" UVux[qX<
S%- kN;
class="com.adt.action.user.ListUser"> %SC Jmn2
<param
,IB\1#
].Yz
=:
name="page.everyPage">10</param> Erw1y,mF
<result NF0_D1Goi
#G#gc`S-,
name="success">/user/user_list.jsp</result> =\lw.59
</action> # Wi?I=,
~61b^L}$
</package> d.?}>jl
#@oB2%&X?
</xwork> VpJKH\)Rt(
b? o
lk>\6o:
]EKg)E
[gT}<W
Ba[,9l[
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 W yM1s+@
- VJx)g
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。 loIb}8
a <C?- g|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 JOuyEPy
opH!sa@U
*;@wPT
1 !_p
1r=cCM
我写的一个用于分页的类,用了泛型了,hoho A,F~*LXm
qFWN._R
java代码: Srx:rUCv
F` 7v
t,r]22I,`
package com.intokr.util; 2PAu>}W*
~Ykn|$_"I
import java.util.List; m%6VwV7U
,<IomA:q4
/** Nf([JP% 4
* 用于分页的类<br> 0Fb];:a
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9)7$U QY
* 0g[ %)C
* @version 0.01 YVccO~!8
* @author cheng !~|-CF0z=
*/ S L
5k^|
public class Paginator<E> { G:1d6[Q5{
privateint count = 0; // 总记录数 ":
vGs_$
privateint p = 1; // 页编号 y@!M<#SEzG
privateint num = 20; // 每页的记录数 2 {?]W/&fS
privateList<E> results = null; // 结果 ;j%I1k%A
b$klm6nMvm
/** k\[(;9sf.
* 结果总数 d@ K-ZMq
*/ O2 >c|=#
publicint getCount(){ 5TJd9:\Af
return count; bY#BK_8 :
} Dy.i^`7\
N" L&Z4Z
publicvoid setCount(int count){ l$&~(YE f
this.count = count; Os<E7l zqO
} F6}RPk\=i
J$51z
/** 3q73L<f
* 本结果所在的页码,从1开始 =dPokLXn
* Kkp dcc
* @return Returns the pageNo. 0Ncpi=6
*/ @e<(o
UE
publicint getP(){ k4iiL<|
return p; yU!1q}L!
} G$f%]A1
I4"p]>Y"
/** qS\#MMsTd
* if(p<=0) p=1 kL1<H%1'
* ?5EH/yV;
* @param p =|-=4.b+|
*/ l^	d
publicvoid setP(int p){ B,\VLX
if(p <= 0) t}eyfflZ
p = 1; %]Z4b;W[Y
this.p = p; '{AB{)1
} ~uc7R/3ss
qA GjR!=^
/** ]P3m=/w
* 每页记录数量 12lX-~[["
*/ MoFM'a9
publicint getNum(){ (|BY<Ac3
return num; Ip'tB4Mq
} ]i#p2?BR
h&i*=&<HP6
/** yIL=jzm`7
* if(num<1) num=1 cuN ]}=D
*/ tQ{/9bN?P
publicvoid setNum(int num){ ;+wB!/k,
if(num < 1) W#bYz{s.
num = 1; tle`O)&uo
this.num = num; D[yyFo,z
} ]$ "eGHX
8NHm#Z3Ol
/** ^+76^*0
* 获得总页数 e>z"{ u(F0
*/ :rL%,o"
publicint getPageNum(){ l?*DGW(t{
return(count - 1) / num + 1; %(6IaqJ[
} 2'@m'4-N
#`u}#(
/** gko=5|c,@
* 获得本页的开始编号,为 (p-1)*num+1 $!_
X9)e
*/ 6&x\!+]F8
publicint getStart(){ '<o3x$6
*
return(p - 1) * num + 1; 4SI~y;c)
} W,@F!8
V#oz~GMB
/** x{:U$[_
* @return Returns the results. wGti|7Tu*
*/ vntJe^IaFd
publicList<E> getResults(){ AU\=n,K7
return results; *Y(59J2
} Y ]([K.I=
1w=.vj<d8
public void setResults(List<E> results){ NVb}uH*i
this.results = results; Y2DL%'K^
} tA#$q;S
*|=D 0
public String toString(){ kK=VG<
:M
StringBuilder buff = new StringBuilder ;}+M2Ec51
8@rYT5e3c
(); ceG\Q2
buff.append("{"); aLh(8 ;$
buff.append("count:").append(count); sYS
8]JU
buff.append(",p:").append(p); #p(c{L!
buff.append(",nump:").append(num); t,9+G<)>H
buff.append(",results:").append 2V@5:tf
*5PQ>d
G
(results); naaKAZ!S
buff.append("}"); |<c9ZS+
return buff.toString(); ,7s>#b'
} w<H Xe
Leb
Kzqe
} G^ GIHdo
U(f@zGV
B!Wp=9)G