Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )6-9)pH@)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b*EXIzQ
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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 wfR&li{
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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 zXZir7NfM
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分页支持类: MzkkcQLK
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java代码: ^:KO_{3E
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package com.javaeye.common.util; 0fArF*
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import java.util.List; /Vww?9U;
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publicclass PaginationSupport { IRW^ok.'b!
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publicfinalstaticint PAGESIZE = 30; tU@zhGb
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privateint pageSize = PAGESIZE; iPj~I
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privateList items; Z9K})47T
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privateint totalCount; DHw<%Z-J
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privateint[] indexes = newint[0]; s{}]D{bc
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privateint startIndex = 0; 7TX2&kMoc
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public PaginationSupport(List items, int UvJ;A
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totalCount){ b5a.go
setPageSize(PAGESIZE); F<|t\KOW
setTotalCount(totalCount); IG ~`i I
setItems(items); (xpn`NA
setStartIndex(0); vFv3'b$;G
} G~,:2
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public PaginationSupport(List items, int p3(2?UO!
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totalCount, int startIndex){ 646JDX[o
setPageSize(PAGESIZE); Fhf<T`
setTotalCount(totalCount); >jg0s)RA'
setItems(items); A8r^)QJP{
setStartIndex(startIndex); A7Po 3n%Q
} u<xo/=Z
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public PaginationSupport(List items, int L2UsqVU
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totalCount, int pageSize, int startIndex){ lLhL`C!
setPageSize(pageSize); i3$$,W!
setTotalCount(totalCount); d+eZub94U
setItems(items); Yk!/ow@.
setStartIndex(startIndex); iUi>y.}"P
} w_tJ7pz8T
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publicList getItems(){ 6%G-Vs]*2
return items; [iP#VM-N
} p>w]rE:}
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publicvoid setItems(List items){ /] ^#b
this.items = items; ^D%Za'
} b aV>N[F&
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publicint getPageSize(){ Lh.b5Q|
return pageSize; ]`g@UtD9`
} mHc>"^R
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publicvoid setPageSize(int pageSize){ $;N* c H~
this.pageSize = pageSize; "qz3u`[o
} "Jq8?FoT
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publicint getTotalCount(){ nI.x
return totalCount; k <iTjI*N
} i:]*P
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publicvoid setTotalCount(int totalCount){ -a,-J]d0+
if(totalCount > 0){ l e4?jQQ@L
this.totalCount = totalCount; #DU26nCL
int count = totalCount / CC=d I
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pageSize; `.jzuX
if(totalCount % pageSize > 0) [epi#]m
count++; |1b_*G4|
indexes = newint[count]; H %JaZ?(
for(int i = 0; i < count; i++){ "5R~(+~<@
indexes = pageSize * tG vG
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i; X|f7K
} 58\&/lYW
}else{ !* Ti}oIo&
this.totalCount = 0; Z>c3
} #6Fez`A
} _.IxRk)T
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publicint[] getIndexes(){ McH>"`
return indexes; -}O1dEn.
} vE@!{*
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publicvoid setIndexes(int[] indexes){ )'17r82a
this.indexes = indexes; lO&3{dOYE
} %~L>1ShtU
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publicint getStartIndex(){ S#)Eom?V
return startIndex; m8'C_U^89
} :I -V_4b
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publicvoid setStartIndex(int startIndex){ p&+;w
if(totalCount <= 0) f Vb-$
this.startIndex = 0; +a-6Q ~
elseif(startIndex >= totalCount) eP*lI<NQ1
this.startIndex = indexes 7K)6^r^
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[indexes.length - 1]; t`*! w|}(1
elseif(startIndex < 0) *Qugv^-
this.startIndex = 0; 0/S_e)U
else{ ^O^l(e!3
this.startIndex = indexes HGm 3+,
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[startIndex / pageSize]; O3TQixE
} pw7[y^[Qg
} 5>BK%`
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publicint getNextIndex(){ WVVJ
int nextIndex = getStartIndex() + q _-7i
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pageSize; 6-?66gmT
if(nextIndex >= totalCount) UnI48Y
return getStartIndex(); ylt`*|$
else J[f;Xlh
return nextIndex; pZ/>[TP(%F
} ,-7R(iMd
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publicint getPreviousIndex(){ sC9&Dgkk
int previousIndex = getStartIndex() - A&nU]R8S
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pageSize; W 4F \}A
if(previousIndex < 0) E<yW\
return0; XC.%za8
else jDQZQ NS
return previousIndex; s
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} ]XI*Wsn
5 ~TdD6}
} [Q=dCX9%
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抽象业务类 m!<\WN6g
java代码: X7s
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/** Mn)@{^
* Created on 2005-7-12 mdRU^n
*/ =$]uoA
package com.javaeye.common.business; 6`f2-f9%iq
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import java.io.Serializable; N!g9*Z
import java.util.List; ANgw"&&>(
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import org.hibernate.Criteria; 66fO7OJs
import org.hibernate.HibernateException; o865(<p
import org.hibernate.Session; F&&$Qn_+
import org.hibernate.criterion.DetachedCriteria; OF\rgz
import org.hibernate.criterion.Projections; L'u\w
import O BN2 ) j
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org.springframework.orm.hibernate3.HibernateCallback; Uw47LP
import o<N nV
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org.springframework.orm.hibernate3.support.HibernateDaoS L'F<ev
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upport; qHxqQ'ks;
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import com.javaeye.common.util.PaginationSupport; JU4qzi
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public abstract class AbstractManager extends () j=5KDu
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HibernateDaoSupport { 92EWIHEWZ
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privateboolean cacheQueries = false; KQ~i<1&j
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privateString queryCacheRegion; B'fb^n<
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publicvoid setCacheQueries(boolean |o\8
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cacheQueries){ lBaR
this.cacheQueries = cacheQueries; )a-Du$kd
} "sG=wjcw^
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publicvoid setQueryCacheRegion(String -4cXRv]
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queryCacheRegion){ YGrg
this.queryCacheRegion = 8?%-'z.
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queryCacheRegion; !_"fP:T>
}
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publicvoid save(finalObject entity){ Ry'= ke
getHibernateTemplate().save(entity); !P-^O
} wYmM"60
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publicvoid persist(finalObject entity){ !1ED~3/X
getHibernateTemplate().save(entity); v#!%GEg1r
} |]c8jG\h
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publicvoid update(finalObject entity){ tQjLOv+?=
getHibernateTemplate().update(entity); :$n=$C-wp
} \ioH\9
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publicvoid delete(finalObject entity){ 'nwx9]q
getHibernateTemplate().delete(entity); 9pX&ZjYP-
} ,]d,-)KX8
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publicObject load(finalClass entity, =17t-
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finalSerializable id){ ?nmn1`UT
return getHibernateTemplate().load RS^lKJ1 U
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(entity, id); 3J5!oF{H
} 4 XAQVq5
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publicObject get(finalClass entity, vMm1Z5S/
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finalSerializable id){ k@'#@
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return getHibernateTemplate().get hUF5fZqii
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(entity, id); fc
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} nYX@J6!
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publicList findAll(finalClass entity){ ^G.B+dG@`x
return getHibernateTemplate().find("from +>r/ 0b
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" + entity.getName()); r_-_a(1R:
} +Nt2
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publicList findByNamedQuery(finalString K[!&b0O
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namedQuery){ vuoQz\
return getHibernateTemplate lw<c2C
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().findByNamedQuery(namedQuery); u)~C;f)
} Y9&,t\ q
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publicList findByNamedQuery(finalString query, DKBSFm{~Q
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finalObject parameter){ %|^fi8!:|
return getHibernateTemplate dF2nEaN0%
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().findByNamedQuery(query, parameter); ce7CcHQ?B
} Bq$rf < W
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publicList findByNamedQuery(finalString query, Z7= `VNHc
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finalObject[] parameters){ #g]vc_V
return getHibernateTemplate Kq;8=xP[
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().findByNamedQuery(query, parameters); ;e1ku|>$
} uA#P'?
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publicList find(finalString query){ _t^{a]/H
return getHibernateTemplate().find `#;e)1
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(query); BEre*J
} z}*9uZ
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publicList find(finalString query, finalObject U
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parameter){ N _86t
return getHibernateTemplate().find p_${Nj
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(query, parameter); \uaJ@{Vug
} osX8eX]\
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public PaginationSupport findPageByCriteria e,Uo#T6J
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(final DetachedCriteria detachedCriteria){ V0P>YQq9s
return findPageByCriteria Q|D @Yd\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @NNq z
} LC'{p
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public PaginationSupport findPageByCriteria PqiB\~o@Z
@CZT
(final DetachedCriteria detachedCriteria, finalint K otrX
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startIndex){ fvdU`*|n)
return findPageByCriteria -bSSP!f
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(detachedCriteria, PaginationSupport.PAGESIZE, ".<DAs j
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startIndex); Na?!;1]_
} tX>
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public PaginationSupport findPageByCriteria 9mmCp&~Z
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(final DetachedCriteria detachedCriteria, finalint HLV2~5Txc
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pageSize, 4DL) rkO
finalint startIndex){ nh!a)]c[
return(PaginationSupport) er!DYv
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getHibernateTemplate().execute(new HibernateCallback(){ y&?6FY
publicObject doInHibernate '<ZlGFt'n
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(Session session)throws HibernateException { #]ypHVE
Criteria criteria = JU^lyi!
8>WC5%f*
detachedCriteria.getExecutableCriteria(session); \\u<S=G
int totalCount = =A!@6Nw
#nK>Z[
((Integer) criteria.setProjection(Projections.rowCount :$m}UA-9
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()).uniqueResult()).intValue(); LYaZ1*
criteria.setProjection xx{PespNt
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(null); }}>q2y
List items = s3R(vd
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criteria.setFirstResult(startIndex).setMaxResults /M3Y~l$
@M5#S7q";
(pageSize).list(); FMClSeO7
PaginationSupport ps = n=c
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new PaginationSupport(items, totalCount, pageSize, 06N}k<10O
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startIndex); /q5v"iX]T
return ps; RWgNo#<
} &'}RrW-s
}, true); TTt#a6eJ
} .tzG_
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public List findAllByCriteria(final lMg+R<$~I
@]-jl}:]
DetachedCriteria detachedCriteria){ :=\Hoz
return(List) getHibernateTemplate B hp-jq'!B
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().execute(new HibernateCallback(){ EodQ*{l
publicObject doInHibernate Xt@Z}B))pu
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(Session session)throws HibernateException { }7
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Criteria criteria = t_qNq{
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detachedCriteria.getExecutableCriteria(session); zBk'{[y9L
return criteria.list(); \3S8 62B7
} D~$r\]av
}, true);
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} zN"J}r:
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public int getCountByCriteria(final P%(O|
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DetachedCriteria detachedCriteria){ 'zGo?a
Integer count = (Integer) #~l(]h@
)
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getHibernateTemplate().execute(new HibernateCallback(){ K3x.RQQ-
publicObject doInHibernate 4*cU<
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(Session session)throws HibernateException { 6DuEL=C
Criteria criteria = KNLfp1!
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detachedCriteria.getExecutableCriteria(session); Wu_kx2h
return V*iH}Y?^p
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criteria.setProjection(Projections.rowCount 5yiK+-iTs
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()).uniqueResult(); J_v$YwE
} M #=]
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}, true); dRaNzK)M
return count.intValue(); YGPy@-,E
} 0 SNIYkGE
} V` 1/SQX
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用户在web层构造查询条件detachedCriteria,和可选的 [.S#rGYk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0#S W!b|%
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PaginationSupport的实例ps。 cvfr)K[0
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ps.getItems()得到已分页好的结果集 JMz;BAHT
ps.getIndexes()得到分页索引的数组 Gmq/3tw
ps.getTotalCount()得到总结果数 ?hWwj6i&
ps.getStartIndex()当前分页索引 =<X?sj5
ps.getNextIndex()下一页索引 `P8Vh+7u
ps.getPreviousIndex()上一页索引 PUBWZ^63
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 'b#0t#|TM
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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 Wr3mQU
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一下代码重构了。 8qu2iPOcZ
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我把原本我的做法也提供出来供大家讨论吧: {jho&Ai
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首先,为了实现分页查询,我封装了一个Page类: S<WdZ=8sA
java代码: D[mSmpjE6&
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/*Created on 2005-4-14*/ aP8H`^DFX>
package org.flyware.util.page; |&[L?
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/** n ;$5Cq!v=
* @author Joa HaYE9/xS
* 2#<xAR
*/ k?z98 >4
publicclass Page { bX*Hi#J~A
nM-h&na{s
/** imply if the page has previous page */ L2pp6bW
privateboolean hasPrePage; _-9@qe
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/** imply if the page has next page */ DV\`Wv
privateboolean hasNextPage; 3'c0#h@VD
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/** the number of every page */ ywb4LKD
privateint everyPage; +S R+x/?z
kRTwaNDOD
/** the total page number */ -x'z
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privateint totalPage; e|p$d:#!
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/** the number of current page */ h|h>u
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privateint currentPage; 5fm?Lxr&?
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/** the begin index of the records by the current sp5eVAd
Q`rF&)Q5
query */ BvR-K\rx
privateint beginIndex; eOXHQjuj
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/** The default constructor */ Pj4/xX
public Page(){ =9z[[dQ|L
%_(H{y_!
} 9(5OeH6o?
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/** construct the page by everyPage '^Ql]% _
* @param everyPage MH{GR)ng:9
* */ {2+L@
public Page(int everyPage){ z j/!In
this.everyPage = everyPage; ~5 *5
} y-j\zK
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/** The whole constructor */ QR
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public Page(boolean hasPrePage, boolean hasNextPage, 5Pd"h S
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int everyPage, int totalPage, ,WG<hgg-U)
int currentPage, int beginIndex){ fuA&7gNC
this.hasPrePage = hasPrePage; &3$z4df
this.hasNextPage = hasNextPage; m^#rB`0;L
this.everyPage = everyPage; d , Y#H0`
this.totalPage = totalPage; `8I&7c
this.currentPage = currentPage; L
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this.beginIndex = beginIndex; %^8^yZz
} RtCkV xaEx
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/** ?APeR,"V
* @return S=nP[s
* Returns the beginIndex. 3Te^
*/ 9:!gI|C
publicint getBeginIndex(){ i-'9AYyw
return beginIndex; K"0PTWt
} i@B[ eta
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/** Qed.4R:o
* @param beginIndex \MmI`$
* The beginIndex to set. w1Ec_y {
*/ VB?Ohk]<
publicvoid setBeginIndex(int beginIndex){ ^kgBa2 7
this.beginIndex = beginIndex; %<\6TZr
} !Yw3 d
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/** ]a!xUg!S
* @return q~59F@
* Returns the currentPage. ;i"*Ll>Q)
*/ Y)$ ;Ax-D
publicint getCurrentPage(){ 2{Chu85
return currentPage; ynB _"mg
} Hw|AA?,0-
u@.>Z{h
/** 2PeR
* @param currentPage #!$GH_
* The currentPage to set. UTSL
*/ J8"[6vI d~
publicvoid setCurrentPage(int currentPage){ LS5vW|]w
this.currentPage = currentPage; :mS# h@l
} 2<][%> '
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/** Z{
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* @return t2V0lyeL
* Returns the everyPage. \y88d4zX
*/ 5hbJOo0BZ
publicint getEveryPage(){ h8X g`C\
return everyPage; 1tJg#/?
} u- o--q
u1~9{"P*
/** %\kOLE2`
* @param everyPage iajX ~kv
* The everyPage to set. _kdL'x
*/ )'hH^(Yu
publicvoid setEveryPage(int everyPage){ I"t(%2*q
this.everyPage = everyPage; /% I7Vc
} N~ ?{UOZd
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/** R.s^o]vT
* @return "ywh9cp
* Returns the hasNextPage. iz~
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*/ e|rg;`AW
publicboolean getHasNextPage(){ oM2UzB{(
return hasNextPage; c=;:R0_'t
} ?6k}ii!c
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/** VN'Wq7>6
* @param hasNextPage Y9=(zOqv
* The hasNextPage to set. ^@"H1
*/ mrJQ#
publicvoid setHasNextPage(boolean hasNextPage){ `s]4AKBO
this.hasNextPage = hasNextPage; i,nm`Z>u
} enTW0U}
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/** JI/_ce
* @return X>I)~z}9#
* Returns the hasPrePage. S/`%Q2za4
*/ s3 ;DG
publicboolean getHasPrePage(){ e*
return hasPrePage; #"ftI7=42
} ur\qOX|{
ycJg%]F*5
/** $LHa?3
* @param hasPrePage {&[9iIf
* The hasPrePage to set. 8*SP~q
*/ 3^StIw{X
publicvoid setHasPrePage(boolean hasPrePage){ S\wW)Pv8
this.hasPrePage = hasPrePage; n q19Q)
} aP&D9%5
}6-ZE9H-v
/** &6j<c a
* @return Returns the totalPage. \@~UDP]7
* zD)pF1,7:8
*/ DOQc"+
publicint getTotalPage(){ fIocq
return totalPage; +-a&2J;J'
} oW$s
xS
f&x0@Q/eON
/** W0zbxJKjd
* @param totalPage [,~TaP}m
* The totalPage to set. U{ ;l0 2S
*/ M0c9pE
publicvoid setTotalPage(int totalPage){ AY SSa 1}
this.totalPage = totalPage; b}G24{
} _0pO8o-x
q+a.G2S
} =6=_/q2
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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 ue8qIZH
l12$l<x&M
个PageUtil,负责对Page对象进行构造: [WB{T3j
java代码: tVqmn
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M]HgIL@9#
/*Created on 2005-4-14*/ (shK
package org.flyware.util.page; me\cLFw
]Y.deVw3i
import org.apache.commons.logging.Log; 7W9~1
.SC
import org.apache.commons.logging.LogFactory; R<zG^m
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/** ^ie^VY($
* @author Joa C2<CWPn<
* 'FzN[% K"
*/ S^cH}-+
publicclass PageUtil { fA^7^0![
*mBJ?{ !
privatestaticfinal Log logger = LogFactory.getLog x7RdZC
\NX Q
(PageUtil.class); 1Qh`6Ya f
=f:(r'm?r.
/** Y'Z+, CNf
* Use the origin page to create a new page ~E=\t9r
* @param page kA7(CqUW
* @param totalRecords mYNEz
@
* @return E=/[s]@5
*/ ~H[%vdR
publicstatic Page createPage(Page page, int ,vG<*|pn
TRKgBK$,
totalRecords){ %HSl)zEo>C
return createPage(page.getEveryPage(), 3AlqBXE"Z<
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page.getCurrentPage(), totalRecords); g-yi xU
} ~4)Y#IxL
X^< >6|)
/** 16@);Ot
* the basic page utils not including exception -{9Gagy2&
m1.B\~S3
handler jxy1
* @param everyPage 3ViM ?p
* @param currentPage /qxJgoa
* @param totalRecords yty`2$O
* @return page =p&sl;PsLw
*/ 4w{-'M.B
publicstatic Page createPage(int everyPage, int 1.SkIu%
5a(<%Q
<"
currentPage, int totalRecords){ 74zSP/G'
everyPage = getEveryPage(everyPage); 7aQcP
currentPage = getCurrentPage(currentPage); 7nz!0I^
int beginIndex = getBeginIndex(everyPage, Isovwd
{TL +7kiX/
currentPage); F@hYA
int totalPage = getTotalPage(everyPage, jNy?[
)
d.pp3D9/
totalRecords); Q
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boolean hasNextPage = hasNextPage(currentPage, *=vlqpG
JCQ:+eqt
totalPage); '; /84j-3F
boolean hasPrePage = hasPrePage(currentPage); p(7QAd4
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returnnew Page(hasPrePage, hasNextPage, DuF7HTN[K
everyPage, totalPage, M^ 5e~y
currentPage, /R%^rz'w
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beginIndex); M}!A]@
} j??tmo
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privatestaticint getEveryPage(int everyPage){ <*YO~S(R
return everyPage == 0 ? 10 : everyPage; O|UxFnB}
} /S/aUvN
l(Cf7o!
privatestaticint getCurrentPage(int currentPage){ ~|R[O^9B
return currentPage == 0 ? 1 : currentPage; uu>lDvR*
} /{DaPqRa
6wpU6NU
privatestaticint getBeginIndex(int everyPage, int T_~KxQ
M5Wl3tZL
currentPage){ Za!w#j%h
return(currentPage - 1) * everyPage; BPWnck=%
} l^,qO3ES
SOH%Q_
privatestaticint getTotalPage(int everyPage, int d~<QAh#rG
_>v0R'
totalRecords){ XOxB
(0@
int totalPage = 0; q2!'==h2i
6{7 3p@
if(totalRecords % everyPage == 0) ycjJbL(.
totalPage = totalRecords / everyPage; ;\s~%~\
else M]B3vPA/v
totalPage = totalRecords / everyPage + 1 ; 3G&0Ciet
&A"e,h(^
return totalPage; p1
4d,}4W
} K_##-6>
BVAr&cu
privatestaticboolean hasPrePage(int currentPage){ lzoeST
return currentPage == 1 ? false : true; ;>C9@S+
} P/`m3aSzX.
"!a`ygqpT
privatestaticboolean hasNextPage(int currentPage, \c68n
M,JA;a, _
int totalPage){ %|jzEBz@
return currentPage == totalPage || totalPage == leIy|K>\m
a hwy_\
0 ? false : true; ,|iy1yg(
} <Cr8V'c
*]'qLL7d
hpjUkGm5
} aG
Ef#A
bpnv &EG
nFj-<!
QmHwn)Ly
6s5b$x
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。
{WKOJG+.
@% H8"A
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 5&G
5eA
2R] XH
0
做法如下: @9<S*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0`Gai2\1@
R|H[lbw
的信息,和一个结果集List: FbBX}n
java代码: PnJ*Zea
u/#&0_
P
u6p5:oJj,
/*Created on 2005-6-13*/ shy
package com.adt.bo; :4iU^6
Hy;901( %
import java.util.List; E+Im~=m$
-^Rb7 g-
import org.flyware.util.page.Page; eB7>t@ED
n_u`B|^Pj
/** EFwL.'Fh
* @author Joa W8x[3,gT
*/ gjQ=8&i
publicclass Result { []rT? -
ret0z|
private Page page; M`bL5J;
r/^tzH's
private List content; 0w'|d@*wV
>j)
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/** pY,O_
t$
* The default constructor ^aT;aP^l
*/ Dw*Arc+3V
public Result(){ ^A- sS~w
super(); ^~,
ndH{
} l3BD
<PB2S
n'ehB%"
/** PK_Fx';ke^
* The constructor using fields zdqnL^wb
* N:OD0m%`)
* @param page 90?,-6
* @param content V8\$`NEP
*/ [4ee <J
public Result(Page page, List content){ *$JB`=Q
this.page = page; a6k(9ZF
this.content = content; fWd~-U0M^
} E3LBPXK
r7RU"H:j8
/** Z6NJ)XQy6F
* @return Returns the content. qP qy4V.;
*/ >H)^6sJ;%b
publicList getContent(){ 'xQna+ %h
return content; jT{f<P0
} \ibCR~W4
Q6eN+i2 ;
/** Zo'/^S
* @return Returns the page. >6XDX=JVI
*/ c%jsu"
public Page getPage(){ ?_8%h`z
return page; o*-h%Z.
} |OOXh[y
&K+
/** ^@ M [t<
* @param content DakLD~H;
* The content to set. ]NbX`'
*/ +g)_4fV0|
public void setContent(List content){ A S`2=w
this.content = content; #NWZ k.S
} >'eB2
t3pZjdLJd
/** B%TXw#|
* @param page P8"6"}B;T
* The page to set. ht2
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*/ D&4u63^
publicvoid setPage(Page page){ yI3Q |731)
this.page = page; ]cn/(U`
} ?]s%(R,B5
} ~5FS|[1L
1NuR/DO
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Y
@bc[
eas
>_&~!Y.Z=
2. 编写业务逻辑接口,并实现它(UserManager, P/C&R-{')
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t:5
Im
UserManagerImpl) umZlIH[7
java代码: D8)O4bh
&/sGh0
oK#\HD4U
/*Created on 2005-7-15*/ kw6cFz
package com.adt.service; j#7wyi5q
zt-'SY
import net.sf.hibernate.HibernateException; +8Of-ZUx
/_$~rW
import org.flyware.util.page.Page; 8$2l^
BPwI8\V
import com.adt.bo.Result; f<g>dQlE
ov?.:M
/** Fl B, (Cm
* @author Joa 7vii9Am7
*/ M4zX*&w.T
publicinterface UserManager { 44'=;/
"Q3PC!7X:5
public Result listUser(Page page)throws KYnW7|*
Sg/:n,68
HibernateException; ;%BhhmR)[
zY]Bu-S3
} CWE Ejl
C<r(-qO{5
=@Q#dDnFu%
,Adus M
/1IvLdPIu
java代码: ]cx"
/d{glOk
^^n+
/*Created on 2005-7-15*/ =#OHxM
package com.adt.service.impl; ZmEG<T05
`
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import java.util.List; "}S9`-Wd|
jHs<s`#h
import net.sf.hibernate.HibernateException; 1 ;_{US5FR
`V]egdO
import org.flyware.util.page.Page; 1;cv-W
import org.flyware.util.page.PageUtil; r{pI-$
aeG#:
Ln+{
import com.adt.bo.Result; ."~7 \E> t
import com.adt.dao.UserDAO; lAdOC5+JX
import com.adt.exception.ObjectNotFoundException; b}ySZlmy
import com.adt.service.UserManager; 9X
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a/`c ef
/** skk-.9
* @author Joa "2)+)Db
*/ :'5G_4y)h
publicclass UserManagerImpl implements UserManager { xDPQG`6
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private UserDAO userDAO; *]{9K
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~
/** T^/Gj|N*
* @param userDAO The userDAO to set. z1Bj_u{
*/ SRA|7g}7W
publicvoid setUserDAO(UserDAO userDAO){ !Z#_X@NFc
this.userDAO = userDAO; D__lqboz
} K!IF?iell
- XE79 fQ
/* (non-Javadoc) 844tXMtPB\
* @see com.adt.service.UserManager#listUser p{A}p9sjx
1$='`@8I
(org.flyware.util.page.Page) LP5eFl`|T
*/ ^ 4u3Q
public Result listUser(Page page)throws o7_MMeQ4
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8h
HibernateException, ObjectNotFoundException { s=H/b$v
int totalRecords = userDAO.getUserCount(); c[wQJc
if(totalRecords == 0) kWZ/ej
throw new ObjectNotFoundException D%c7JK
,omp F$%
("userNotExist"); s`8M%ZLu
page = PageUtil.createPage(page, totalRecords); 6.
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z
List users = userDAO.getUserByPage(page); w\"n!^ms
returnnew Result(page, users); 1R5\GKF6o
} l|@/?GaH
E3CiZ4=5
} AmT|%j&3
~pd1)
%\(y8QV
"!%w9
dO 1-c`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 s${T*)S@G
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询,接下来编写UserDAO的代码: .LXh]I*
3. UserDAO 和 UserDAOImpl: '(3Nopl
java代码: |d/x~t=
G+#| )V
BNL8hK`D
/*Created on 2005-7-15*/ z:ru68
package com.adt.dao; 9A/Kn]s(jj
/%ODJ1 M
import java.util.List; Z,|1G6f@
"Cyo<|
import org.flyware.util.page.Page; Q.pEUDq/
Se^/VVm
import net.sf.hibernate.HibernateException; w-0O j
a'_MhJ zs
/** J'G`=m"-'
* @author Joa ?l\gh1{C
*/ G*vpf~q?
publicinterface UserDAO extends BaseDAO { +!L_E6pyXE
X%4uShM
publicList getUserByName(String name)throws o@<6TlZM
in=k:j,U0
HibernateException; c{m
;"ZCFS
O]Ry3j
publicint getUserCount()throws HibernateException; e_>rJWI}
BDRYip[Sa
publicList getUserByPage(Page page)throws DuO%B
#FQm/Q<0
HibernateException; eZR8<Z%
>?G|Yz*kEJ
} 9z|>roNe
XvA0nEi
b2}QoJ@`
DSDl[;3O{s
m]-v IUpb
java代码: x;ICV%g/
L!8 -:)0b
8zCGMhd
/*Created on 2005-7-15*/ 2vh!pez_
package com.adt.dao.impl; 9?g]qy,1)
sO{0hZkc
import java.util.List; Y6;0khp
wQdW
lon
import org.flyware.util.page.Page; M k'n~.mb
(jo(bbpj
import net.sf.hibernate.HibernateException; aV?}+Y{#
import net.sf.hibernate.Query; A5.'h<
{x&jh|f`g
import com.adt.dao.UserDAO; s!j(nUd/
+/@ZnE9s
/** os(Jr!p_=
* @author Joa (AM,4)lW,
*/ +9Hk+.
public class UserDAOImpl extends BaseDAOHibernateImpl Z0F>"Z_qn
I(?|Ox9"?
implements UserDAO { 4ye`;hXy
Y&05
*b"
/* (non-Javadoc) &aevR^f+
* @see com.adt.dao.UserDAO#getUserByName PFDWC3<
"#\bQf}
(java.lang.String) +}(B856+
*/ ?9('o\N:
publicList getUserByName(String name)throws AG$-U2ap
?) ,xZ1"
HibernateException { St3(1mApl
String querySentence = "FROM user in class bW
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y1\^v_.^
com.adt.po.User WHERE user.name=:name"; St7D.|
Query query = getSession().createQuery Zm;
+Ku>
)HzITsFZKT
(querySentence); #a'x)$2;R|
query.setParameter("name", name); :`>+f.)
return query.list(); ,$6MM6W;-F
} ~\)&{'
QzFv ;
/* (non-Javadoc) #H|j-RM2
* @see com.adt.dao.UserDAO#getUserCount() Y%CL@G60
*/ M;p q2$
publicint getUserCount()throws HibernateException { !(ux.T0
int count = 0; l6`d48U
String querySentence = "SELECT count(*) FROM y9G 57D
S)'q:`tZo
user in class com.adt.po.User"; dnX`F5zd
Query query = getSession().createQuery qs
c-e,rl
Pu%>j'A
(querySentence); |Z7bd^
count = ((Integer)query.iterate().next !{]v='
>e$^#\D
()).intValue(); %\{?(baOA
return count; C(t6;&H
} bF Y)o Z
/<?X-IDz.{
/* (non-Javadoc) y8~)/)l&
* @see com.adt.dao.UserDAO#getUserByPage
S9"y@F
<
VU+ s7L0
(org.flyware.util.page.Page) 6B;_uIq5
*/ _[OEE<(
publicList getUserByPage(Page page)throws HyX4ob[X
_@~kYz
HibernateException { KEVy%AP=*h
String querySentence = "FROM user in class 7Yw\%}UL
G|G?h
com.adt.po.User"; c7nk~K[6
Query query = getSession().createQuery E=1/
l#vw
L15
(querySentence); u.L8tR:(
query.setFirstResult(page.getBeginIndex()) m/F(h-?
.setMaxResults(page.getEveryPage()); : {N3o:
return query.list(); In9|n^=H@
} ^SSOh#
-Ib+ /'
} N13;hB<
'3_B1iAv
zUUxxS_?
@8M2'R\
QWW7I.9r
至此,一个完整的分页程序完成。前台的只需要调用 I`$I0
/glnJ3
userManager.listUser(page)即可得到一个Page对象和结果集对象 *6x^w%=A
&CeF^
的综合体,而传入的参数page对象则可以由前台传入,如果用 wyzBkRg.
komxot[[
webwork,甚至可以直接在配置文件中指定。 >*i8RqU
"1`i]Y\'
下面给出一个webwork调用示例: %:;[M|.
java代码: v^18o$=K",
h, 6S$,UI
>RqT7n8h
/*Created on 2005-6-17*/ Lz>{FOR
package com.adt.action.user; o`1V
/
-qt}
import java.util.List; BM$tywC
pQMpkAX
import org.apache.commons.logging.Log; & Dl'*|
import org.apache.commons.logging.LogFactory; OTHd1PSOu
import org.flyware.util.page.Page; ;YXr G
Ty4%du6?d
import com.adt.bo.Result; yJ`1},^
import com.adt.service.UserService; F-7b`cF9[r
import com.opensymphony.xwork.Action; yb.|7U?/x
4C9"Q,o%&
/** rB&j"p}Q
* @author Joa nTy,Jml
*/ f,
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publicclass ListUser implementsAction{ aU8Ti8A>
AFB 7s z
privatestaticfinal Log logger = LogFactory.getLog : )"jh`
i~s9Ot
(ListUser.class); |e;z"-3
=qR7-Q8B
private UserService userService; ABe^]HlH
jc~*#\N
private Page page; V #\ZS{'J
3k[<4-
privateList users; (Rg!km%2T
d8
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/* +-YuBVHL
* (non-Javadoc) hsVJ&-#
* 6V6g{6W,/
* @see com.opensymphony.xwork.Action#execute() u{nWjqrM*5
*/ \C2P{q/m
publicString execute()throwsException{ -L50kk>h
Result result = userService.listUser(page); nMdN$E
page = result.getPage(); ="[](X^ l
users = result.getContent(); X%1.mTU~K
return SUCCESS; `iayh
} o-<_X&"a|5
w|FVqX
/** Csm!\I
* @return Returns the page. 0?;Hmq3
*/ l3#dfW{
public Page getPage(){ p6l@O3
return page; DCzPm/#b
} X*yp=qI
,u^0V"hJ
/** pV|?dQ
* @return Returns the users. !vp!\Zj7o
*/ >N1]h'q>
publicList getUsers(){ ^(JbJ@m/
return users; F j('l
} ^JVP2L>o*
s@[t5R
/** v oS"X
* @param page 0HuRFl
* The page to set. A.x}%v,E
*/ TaO;r=2
publicvoid setPage(Page page){ >^GCSPe
this.page = page; s1$#G!'
} Cj9O[
v/+}FS=
/** &b")`p&K
* @param users zd4y5/aoS
* The users to set. q/-j`'A_pb
*/ +F&]BZ
publicvoid setUsers(List users){ (KImqB$i.
this.users = users; 2.2a2.I1
} `(suRp8!
JwVC?m).
/** =usDI<3r
* @param userService NKhR%H
* The userService to set. q&6=oss!
*/ A1}+j-D7!y
publicvoid setUserService(UserService userService){ >d
V@9
this.userService = userService; '#::ba[9w
} Wc>)/y5$
} v+bjC
xxcDd_z
NRF%Qd8I/2
B^Mtj5Oc
+p6\R;_E
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, j6(IF5MqP
/G+gk0FW
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 (jFE{M$-
0BE^qe
么只需要: U (7P X`1
java代码: )nxIxr0d-
Cbvl( (
-" K:ve(K
<?xml version="1.0"?> Z=8CbS).
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork x%ag.g2I
[4rMUS7-m"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;]x5;b9`
gt (nZ
1.0.dtd"> ;-^9j)31+F
)'|W[Sh?
<xwork> .: ;Hh~
=U`c
}dhS
<package name="user" extends="webwork- 1)Bi>X
.3&OFM
interceptors"> d'fpaLV
iPpJ`i#@+
<!-- The default interceptor stack name zNJyF;3
=:8=5tj
--> <yO9j
<default-interceptor-ref 7Q}@L1A9F,
h
l'k_<a*
name="myDefaultWebStack"/> gdNp2b
7/!C
<action name="listUser" Dy@NgHe
l #z`4<
class="com.adt.action.user.ListUser"> o?+e_n=
<param e91d~
FWTl:LqFO
name="page.everyPage">10</param> P"@^'yR5WK
<result /loNOutw
xTm&`Xo
name="success">/user/user_list.jsp</result> XhV"<&v
</action> --)[>6)I
#eyx
</package> B*N 8:u
l= S_#
</xwork> KL~sEli
Kp;o?5H
L$Z_j()2
h1)\.F4G
dL)5~V8s
_'a4I;
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 sH: &OaA
{v
0(0
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。 I!'(>VlP7
$,42h
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 1bs95Fh9Q
vb!KuI!:p
3$;v# P$%N
K\Q
1/})
c7wgjQ[
我写的一个用于分页的类,用了泛型了,hoho &>+Z$ZD
)6WU&0>AU8
java代码: S3cQC`^
M!'tD!NWc
N6'Y
N10
package com.intokr.util; ;\.&FMi
m#'9)%t!J
import java.util.List; s:P-F0q!&
ZVU)@[s
/** 5]+eLKXB
* 用于分页的类<br> w2GY,,R
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 6j#5Ag:
* XWV ~6"
* @version 0.01 ljmHX2p
* @author cheng (qdk
&
*/ 2Y{9Df
public class Paginator<E> { 4+:u2&I
privateint count = 0; // 总记录数 b\mN^P~>A
privateint p = 1; // 页编号 rD?o97
privateint num = 20; // 每页的记录数 s]OXB {M
privateList<E> results = null; // 结果
t-/^ O
7lu;lAAP
/** J(60eTwQ
* 结果总数 P6rL;_~e
*/ [MG:Ym).2`
publicint getCount(){ 4V5*6O9(u
return count; UqbE
} \W!<xE
0"Hf6xz
publicvoid setCount(int count){ (aLnbJeJ
this.count = count; QKxuvW
} nor`w,2VF
s!Vtwp9
/** ~Tolz H!
* 本结果所在的页码,从1开始 5E}i<}sq5
* S1JB]\
* @return Returns the pageNo. on|>"F`pb
*/ u#QQCgrs
publicint getP(){ \)hmg
return p; R?R6|4
} ZN^Q!v
x($1pAE
/** ( ;q$cKy
* if(p<=0) p=1 DlP=R
* N !:&$z-
* @param p ~mU#u\r(*
*/ =n!8>8d
publicvoid setP(int p){ klKt^h-
if(p <= 0) Q_S
fFsY
p = 1; Ghz)=3
this.p = p; dc *#?G6^
} #PGExN3e
BDA\9m^3
/** >:Ec
* 每页记录数量 R?k1)n
*/ Z|.. hZG
publicint getNum(){ P`0aU3pl
return num; M II]sF
} m-K6y7t
aOOY_S
E
/** mtp[]
* if(num<1) num=1 ;a|A1DmZ
*/ e_e|t>nQ
publicvoid setNum(int num){ u:k#1Nn!
if(num < 1) Vs(;al'
num = 1; #t\Oq9}^
this.num = num; tfsG
P]9$
} 7~
2X/
[69aTl>/
/** /#HY-b
* 获得总页数 v^pE=f*/
*/ PGJ?=qXr#
publicint getPageNum(){ /lUb9&yV
return(count - 1) / num + 1; #Ew}@t9
} =i.[|g"
(jXgJ" m
/** ?tBEB5
* 获得本页的开始编号,为 (p-1)*num+1 7dLPy[8";t
*/ J{91 t |
publicint getStart(){ ='f>p+*c%
return(p - 1) * num + 1; "8N]1q:$4
} f-#fi7
nBQG.3
/** @$aCUJ/mE
* @return Returns the results. R8axdV9(
*/ 5s0H4 ?S
publicList<E> getResults(){ edch'H^2+P
return results; @0aUWG!k
} c~cYN W:
6oC(09
public void setResults(List<E> results){ VF4F7'
this.results = results;
n1v%S"^
} 1m&(3%#{
dJ$}]
public String toString(){ PR Y)hb;1
StringBuilder buff = new StringBuilder 6(wpf^br2
`XTu$+
(); K[sfsWQ.
buff.append("{"); b2z~C{l
buff.append("count:").append(count); 1=s%.0
buff.append(",p:").append(p); -.xs=NwB.|
buff.append(",nump:").append(num); &9'6hMu
buff.append(",results:").append 0 {w?u %'
J,k{Bm
(results); E*[X\70
buff.append("}"); \wMr[_LW
return buff.toString(); -~jM=f$
} e-Eoe_k
.
a~J.0co
} Lq yY??\@
H -`7T;t~
(fq>P1-