Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 SY$%!!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )>Lsj1qk
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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 V.-?aXQ *
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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 ~<Lf@yu-{
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分页支持类: Cir =(
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java代码: xLD6A5n,[
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package com.javaeye.common.util; `Eu(r]:W
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import java.util.List; HJ'93,
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publicclass PaginationSupport { R_N<j
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publicfinalstaticint PAGESIZE = 30; 7O9s5
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privateint pageSize = PAGESIZE; G^(&B30V
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privateList items; V?O%k d
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privateint totalCount; jo |q,t
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privateint[] indexes = newint[0]; b #^aM
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privateint startIndex = 0; EU@mrm?
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public PaginationSupport(List items, int =Hx~]1
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totalCount){ hZ'oCRM
setPageSize(PAGESIZE); QlS5B.h,
setTotalCount(totalCount); x ?V/3zW
setItems(items); 6_y|4!,:W
setStartIndex(0); 3'"M31iA
} op|mRJBq;
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public PaginationSupport(List items, int {4QOUqA u
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totalCount, int startIndex){ 7>zKW?
setPageSize(PAGESIZE); @*uX[)
setTotalCount(totalCount); 9V],X=y~
setItems(items); J@GfO\
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setStartIndex(startIndex); vaf9b}FL
} YT5>pM-%
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public PaginationSupport(List items, int 0o<qEo^
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totalCount, int pageSize, int startIndex){ }]~}DHYr
setPageSize(pageSize); NqZRS>60v
setTotalCount(totalCount); '<0q"juXE
setItems(items); q%k+x)
setStartIndex(startIndex); TN
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} bSr 'ji
r9M={jC
publicList getItems(){ Z M+Hb_6f
return items; tRy
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} ZmULy;{<)
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publicvoid setItems(List items){ UC1!J
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this.items = items; +r0eTP=zf
} VRX"
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publicint getPageSize(){ Jrk^J6aa
return pageSize; qp W#!Vbx
} 2ZO'X9
j>o +}p?3I
publicvoid setPageSize(int pageSize){ B
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this.pageSize = pageSize; <]'"e]
} @g75T` N
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publicint getTotalCount(){ 0H3T'J%r
return totalCount; Q@2tT&eL
} GVEWd/:X(
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publicvoid setTotalCount(int totalCount){ Y(y9l{'
if(totalCount > 0){ W"kw>JEt
this.totalCount = totalCount; VM]IL%AN
int count = totalCount / &{ {DS
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pageSize; N}Ks[2
if(totalCount % pageSize > 0) ,z1!~gIal
count++; ,w%oSlOu
indexes = newint[count]; i$ L]X[
for(int i = 0; i < count; i++){ eUkoVr
indexes = pageSize * JQ_gM._3
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i; CjQ"o Qw
} 5FSv"=
}else{ v1C.\fL
this.totalCount = 0; Tq84Fn!HJ>
} T'M66kg
} _g 4/%
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publicint[] getIndexes(){ F36ViN\b
return indexes; yb{Q, Dz
} O4/n!HOb
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publicvoid setIndexes(int[] indexes){ ;x-H$OZX
this.indexes = indexes; |2@en=EYk
} v{2DBr
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publicint getStartIndex(){ b#g
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return startIndex; P!y`$Ky&
} yK077zH_
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publicvoid setStartIndex(int startIndex){ WkaR{{nM
if(totalCount <= 0) =u8D!AxT
this.startIndex = 0; fT3*>^Uv
elseif(startIndex >= totalCount) T@|l@xm~L
this.startIndex = indexes |WAD $3
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[indexes.length - 1]; g6g$nY@Jm
elseif(startIndex < 0) hoR=%pC*
this.startIndex = 0; #jZ@l3
else{ {KDgK
this.startIndex = indexes 9U)t@b
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[startIndex / pageSize]; 0i\',h}9
} h4anr7g{
} EF=dXm/\
7"q+"0G
publicint getNextIndex(){ Q0cY/'>4
int nextIndex = getStartIndex() + x48'1&m
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pageSize; tKZ&1E
if(nextIndex >= totalCount) `\jTpDV_W
return getStartIndex(); h.V]f S
else ADGnBYE
return nextIndex; &|N%#pYS
} vWl[l
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publicint getPreviousIndex(){ }t|Plz
int previousIndex = getStartIndex() - 7%9)C[6NSs
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pageSize; T^$g N|
if(previousIndex < 0) <jUrE[x
return0; >`89N'lZBm
else %l}Q?Z
return previousIndex; 0)AM-/"
} BF36V\
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} vJRnBq+y
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抽象业务类 Y}LLOj@L
java代码: tqf&N0*
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/** dC`tN5
* Created on 2005-7-12 _1sMY hI
*/ pp~3@_)b
package com.javaeye.common.business; ]4Y/x i-
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import java.io.Serializable; lc[XFc
import java.util.List; a}KK{Vqo`
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import org.hibernate.Criteria; @P:R~m2
import org.hibernate.HibernateException; 4.|-m.a
import org.hibernate.Session; Y{Da+
import org.hibernate.criterion.DetachedCriteria; e&QS#k
import org.hibernate.criterion.Projections; z2w;oM$g
import 'y9*uT~
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org.springframework.orm.hibernate3.HibernateCallback; wE$s'e
import 5"JU?e59M
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org.springframework.orm.hibernate3.support.HibernateDaoS [ -ISR7D
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upport; r C_d$Jv
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import com.javaeye.common.util.PaginationSupport; TDlZ!$g(
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public abstract class AbstractManager extends q2e]3{l3
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HibernateDaoSupport { 6&89~W{
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privateboolean cacheQueries = false; iJdP>x
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privateString queryCacheRegion; 3Y
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publicvoid setCacheQueries(boolean +UxI{,L
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cacheQueries){ 4\M8BRuE
this.cacheQueries = cacheQueries; 4`nqAX~'f
} L=,OZ9aA
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publicvoid setQueryCacheRegion(String qZaO&"q
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queryCacheRegion){ D?e"U_
this.queryCacheRegion = +W9]ED
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queryCacheRegion; `=79i$,,t
} -!cIesK;<
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publicvoid save(finalObject entity){ Dl%?OG<
getHibernateTemplate().save(entity); 9x=3W?K:,
} %[wTz$S"
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publicvoid persist(finalObject entity){ =7 VCtd/
getHibernateTemplate().save(entity); :NuR>~
} d.`&0
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publicvoid update(finalObject entity){ 3DW3LYo{
getHibernateTemplate().update(entity); 2F1ZAl
} *g1L$FBG
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publicvoid delete(finalObject entity){ ic-IN~J-
getHibernateTemplate().delete(entity); ASW4,% cl
} Ep mJWbU
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publicObject load(finalClass entity, jYWw.g<
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finalSerializable id){ {"m0)G,G
return getHibernateTemplate().load p1D()-
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(entity, id); HT"gT2U+
} @EHIp{0.
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publicObject get(finalClass entity, IIxJqGN:
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finalSerializable id){ s~J=<)T*6
return getHibernateTemplate().get <F7V=Er
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(entity, id); WmNYO,>
} uEx9-,!
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publicList findAll(finalClass entity){ nUc;/
return getHibernateTemplate().find("from VD$Eb
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" + entity.getName()); /s|{by`we4
} :y#T9R9
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publicList findByNamedQuery(finalString o.Oq__ >$H
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namedQuery){ )TU<:V
return getHibernateTemplate )iU^&@[S
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().findByNamedQuery(namedQuery); J &YQ]l
} =g~W%})
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publicList findByNamedQuery(finalString query, ;cKH1
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finalObject parameter){ \9)#l#m
return getHibernateTemplate 9#k0_vDoW
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().findByNamedQuery(query, parameter); *N F$1
} 3qi_]*dD
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publicList findByNamedQuery(finalString query, q8xd*--#
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finalObject[] parameters){ *HE^1IEl
return getHibernateTemplate L8&D(wh/f
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().findByNamedQuery(query, parameters); !msNEE@[
} -(#-I$z
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publicList find(finalString query){ ;`(R7X
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return getHibernateTemplate().find MBw-*K'?zB
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(query); _1|$P|$P.
} JA^v
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publicList find(finalString query, finalObject #BY`h~&T
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parameter){ 6/tI8H3E
return getHibernateTemplate().find dE5D3ze
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(query, parameter); pQWHG#?7
} #NN ewzC<*
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public PaginationSupport findPageByCriteria ^jD1vUL 2:
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(final DetachedCriteria detachedCriteria){ \+nGOvM
return findPageByCriteria " aq'R(/`c
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Men
(detachedCriteria, PaginationSupport.PAGESIZE, 0); .DguR2KT
} Vz%OV}\
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public PaginationSupport findPageByCriteria TDNf)Mm
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(final DetachedCriteria detachedCriteria, finalint o3N] `xD'
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startIndex){ 6f)2 F<
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return findPageByCriteria L}%dCe
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(detachedCriteria, PaginationSupport.PAGESIZE, edvFQ#,d
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startIndex); ]lBGyUJn
} g(hOg~S\E
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public PaginationSupport findPageByCriteria 'g)n1 {
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(final DetachedCriteria detachedCriteria, finalint d=3'?l`
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pageSize, T!2=*~A
finalint startIndex){ jqnCA<G~B-
return(PaginationSupport) D'_Bz8H!p
}< 5F
getHibernateTemplate().execute(new HibernateCallback(){ C~4PE>YtTv
publicObject doInHibernate +wO#'D
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(Session session)throws HibernateException { ~DF:lqwWP
Criteria criteria = TNwKda+
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detachedCriteria.getExecutableCriteria(session); v;EQ, NL
int totalCount = <a^Oj LLU
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((Integer) criteria.setProjection(Projections.rowCount >mq,}!n
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()).uniqueResult()).intValue(); jd-glE,Y/
criteria.setProjection K^[#]+nQ
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(null); Ao9R:|9
List items = DcD{*t?x
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criteria.setFirstResult(startIndex).setMaxResults JXqr3Np1
?>
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(pageSize).list(); GqKsK
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PaginationSupport ps = hJ;$A*Y
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new PaginationSupport(items, totalCount, pageSize, Wp0
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startIndex); YT#3n
return ps; aA'TD:&p1
} s5&@Cxzl
}, true); `~BZ1)@
} tY|8s]{2
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public List findAllByCriteria(final G}d-(X
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DetachedCriteria detachedCriteria){ p#P~Q/;
return(List) getHibernateTemplate |N /G'>TS
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().execute(new HibernateCallback(){ N)2f7j4C&
publicObject doInHibernate Z.PBu|Kx
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(Session session)throws HibernateException { 23F/\2MSG
Criteria criteria = NAC_pM&B
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detachedCriteria.getExecutableCriteria(session); 7- d.ZG
return criteria.list(); wK_]/Q-L
} :mppv8bh
}, true); -Z-f1.Dm5
} )u%je~Vw
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public int getCountByCriteria(final feM6K!fL`
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DetachedCriteria detachedCriteria){ bm~W
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Integer count = (Integer) C4$:mJ>y
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getHibernateTemplate().execute(new HibernateCallback(){ 1T&Rc4$Sn7
publicObject doInHibernate jKIxdY:U
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(Session session)throws HibernateException { 9pn>-1NJ
Criteria criteria = BaI $S>/Q
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detachedCriteria.getExecutableCriteria(session);
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return
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criteria.setProjection(Projections.rowCount gmKGy@]
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()).uniqueResult(); nQX+pkJ
} (IqZ@->nw
}, true); /1=4"|q>h'
return count.intValue(); MM_k
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} _9 .(a
} fEf_F
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用户在web层构造查询条件detachedCriteria,和可选的 d_UN0YT<
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 v4,h&JLt
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PaginationSupport的实例ps。 g,tjm(
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ps.getItems()得到已分页好的结果集 M-L2w"
ps.getIndexes()得到分页索引的数组 LsEXM-
ps.getTotalCount()得到总结果数 H={DB
ps.getStartIndex()当前分页索引 <#=N
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ps.getNextIndex()下一页索引 /@ !CKh`
ps.getPreviousIndex()上一页索引 :o-,SrORM
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q\Q{sv_
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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 #4MBoN(3
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一下代码重构了。 ptatzp]c#
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我把原本我的做法也提供出来供大家讨论吧: 6vuq1
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首先,为了实现分页查询,我封装了一个Page类: jUv!9Y}F
java代码: Ee)[\Qjn
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/*Created on 2005-4-14*/ ~CB[9D=
package org.flyware.util.page; OaJB=J%
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/** _\Q^x)w6
* @author Joa t"hYcnC
* }I|u'#n_
*/ T{V/+RM
publicclass Page { 8`4<R6]LKB
M` q?Fk
/** imply if the page has previous page */ E J$36
privateboolean hasPrePage; {,*"3O:\:
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/** imply if the page has next page */ [b%:.bjY
privateboolean hasNextPage; )vmA^nU>
V@>r*7\F
/** the number of every page */ GRb*EeT
privateint everyPage; ] h-,o
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q)H1pwxD
/** the total page number */ u p.Q>28r
privateint totalPage; l Z#o+d2Y
/V3=KY`_J
/** the number of current page */ F:*W5xX
privateint currentPage; sK{l 9
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/** the begin index of the records by the current .Ha'p.
56^+;^f^`
query */ JdIlWJY
privateint beginIndex; CTWn2tpW
t+5E#!y
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/** The default constructor */ &_JD)mM5
public Page(){ CkJCi
7.DtdyM
} ,Jc m+Wb
^w ] /
/** construct the page by everyPage lb'GXd %
* @param everyPage vN2u34
* */ d(g^M1m
public Page(int everyPage){ [
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this.everyPage = everyPage; 91Uj}n%
} iX0iRC6f
pF
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/** The whole constructor */ #cj6{%c4
public Page(boolean hasPrePage, boolean hasNextPage, fc/ &X
? uYu`Ojzr
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int everyPage, int totalPage, 8ElKD{.BU8
int currentPage, int beginIndex){ Z%I
this.hasPrePage = hasPrePage; ;'81jbh
this.hasNextPage = hasNextPage; jTLSdul+
this.everyPage = everyPage; z4&iK)x
this.totalPage = totalPage; vG \a1H
this.currentPage = currentPage; ?Ma~^0
this.beginIndex = beginIndex; ypJ".
} S1D@vnZ3O\
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/** Wrr cx(
* @return :4^\3~i1X
* Returns the beginIndex. hFiIW77s2
*/ piU/&
publicint getBeginIndex(){ c/_+o;Bc
return beginIndex; M$0u1~K
} -s 6![eV
qlA7tU2p&
/** k`GA\&zt
* @param beginIndex odg<q$34
* The beginIndex to set. ,39aF*r1Q
*/ `R"I;qV
publicvoid setBeginIndex(int beginIndex){ ]7;\E\o
this.beginIndex = beginIndex; 0* /{4)r
} BTM),
w2
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/** )sho*;_o
* @return :ss,Hl
* Returns the currentPage. XUuu-wm:}
*/ 97K[(KE
publicint getCurrentPage(){ ljKrj
return currentPage; 88c<:fK
} $lhC{&tBV
7LO%#No",
/** C/(M"j M
* @param currentPage ]v#r4Ert
* The currentPage to set. c1%H4j4/
*/ CRbdAqofV
publicvoid setCurrentPage(int currentPage){ fX
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this.currentPage = currentPage; w
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} E~LTb)
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/** nenU)*o
* @return Mwgu93?
* Returns the everyPage. lo'W1p
*/ q5>v'ZSo
publicint getEveryPage(){ F@R1:M9*
return everyPage; ~tOAT;g}q
} Q[+ac*F=Y
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/** &qS[%K )
* @param everyPage w`l{LHrR
* The everyPage to set. &K/FyY5
*/ \^#~@9
publicvoid setEveryPage(int everyPage){ K(XN-D/c
this.everyPage = everyPage; 8u!"#S#>a
}
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/** iMfngIs |
* @return XJ2^MF2BU
* Returns the hasNextPage. kh%{C]".1
*/ 3=W!4
publicboolean getHasNextPage(){ 9o>8o
return hasNextPage; Z'H5,)j0R
} ?8W("W
g#]wLm#
/** @y31NH(
* @param hasNextPage ,RN:^5 p
* The hasNextPage to set. "QvmqI>
*/ QMEcQV>
publicvoid setHasNextPage(boolean hasNextPage){ (|wz7AY2
this.hasNextPage = hasNextPage; R0oKbs{
} WW~+?g5
G|\^{5
/** f<A5?eKw
* @return .Vq)zi1<
* Returns the hasPrePage. ]tY
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*/ &CwFdx:Ff
publicboolean getHasPrePage(){ r=c<--_@
return hasPrePage; N25V]
} ;;A2!w{}[i
97)/"i e
/** m[k_>e\u
* @param hasPrePage 85;b9k&\M
* The hasPrePage to set. ?'"X"@r5
*/ 9;xM%
publicvoid setHasPrePage(boolean hasPrePage){ TNJG#8 n%Y
this.hasPrePage = hasPrePage; MQKfJru7
} |pa$*/!NT
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/** Et_V,s<|
* @return Returns the totalPage. 0| ;
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* UU8pz{/
*/ HK+/:'Pu
publicint getTotalPage(){ jSc#+_y
return totalPage; zS]8V?`
} 7)%+=@
.CSS}4
/** <'G~8tA%v
* @param totalPage Xv@SxS-5l
* The totalPage to set. L4L2O7
*/ ){r2T1+-%
publicvoid setTotalPage(int totalPage){ qF iLh9=D
this.totalPage = totalPage; \
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} R>`}e+-D
4`Ic&c/
} sKyPosnP
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ly WwGR
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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 @xc',I
:R.&`4=X
个PageUtil,负责对Page对象进行构造: DQwGUF'(
java代码: &F}"Z(B<wK
^uJU}v:
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/*Created on 2005-4-14*/ 9Ct`
package org.flyware.util.page; ud fe
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import org.apache.commons.logging.Log; n4lutnF
import org.apache.commons.logging.LogFactory; |j3'eW&=
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sl
/** !`bio cA
* @author Joa ,7XtH>2s
* SR*wvQnOx
*/ H'F6$ypoS
publicclass PageUtil { >%E([:$A
m0{ !hF[^
privatestaticfinal Log logger = LogFactory.getLog ) _ I,KEe
5d@t7[]
(PageUtil.class); ( )sTb>L
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/** 7=]i~7uy
* Use the origin page to create a new page ,
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* @param page +\Q?w?DE|
* @param totalRecords m*X[ Jtr
* @return 'B0{U4?
*/ Jgu94.;5
publicstatic Page createPage(Page page, int -CH`>
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totalRecords){ [7m1Q<
return createPage(page.getEveryPage(), ny-7P;->8
I]!^;))
page.getCurrentPage(), totalRecords); d2s OYCKe
} g]UBZ33y
q2:K4
/** Q
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* the basic page utils not including exception B^D(5
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handler q %A?V_
* @param everyPage )5fQ$<(Z
* @param currentPage HyiFy7j
* @param totalRecords .}')f;jH5<
* @return page !se0F.K
*/ W0jZOP5_.$
publicstatic Page createPage(int everyPage, int [#YE^[*qK
H&b3{yOa
currentPage, int totalRecords){ )rLMIk
everyPage = getEveryPage(everyPage); BK,sc'b
currentPage = getCurrentPage(currentPage); l<(Y_PE:
int beginIndex = getBeginIndex(everyPage, ~7!7\i,Y8\
v&FF|)$
currentPage); w#i[_
int totalPage = getTotalPage(everyPage, ZDL']*)'
z'p:gv]
totalRecords); Da$r `
boolean hasNextPage = hasNextPage(currentPage, g/UaYCjM
Y,8KPg@W
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); 0tk#Gs[
VCy5JH
returnnew Page(hasPrePage, hasNextPage, clI*7j.4E#
everyPage, totalPage, gfU-"VpHE
currentPage, &/.hx(#d
V E2tq k%
beginIndex); ;DnUQj
} c^8o~K>w84
+*oS((0s
privatestaticint getEveryPage(int everyPage){ d+iR/Ssc
return everyPage == 0 ? 10 : everyPage; e7u^mJ
} ZV}X'qGaq
+D#Z n!P
privatestaticint getCurrentPage(int currentPage){ 8&"(WuZ@
return currentPage == 0 ? 1 : currentPage; zq5'i!s !0
} z<gu00U7
4(?G6y)
privatestaticint getBeginIndex(int everyPage, int aKF*FFX
Q-rL$%~='
currentPage){ Y<\^7\[x
return(currentPage - 1) * everyPage; 'cDx{?
} cD1o"bq
&$`hQgi
privatestaticint getTotalPage(int everyPage, int ihT~xt
URcR
totalRecords){ AgF5-tz6x
int totalPage = 0; +)nT|w45
iV.p5FD
if(totalRecords % everyPage == 0) .'[/|4H
totalPage = totalRecords / everyPage; M^rM-{?<
else
>95TvJ
totalPage = totalRecords / everyPage + 1 ; Hg}I]!B
{mE! Vf
return totalPage; p<WFqLe(":
} 7=4 A;Ybq
VVWM9x
privatestaticboolean hasPrePage(int currentPage){ RaSz>-3d
return currentPage == 1 ? false : true; e2$]g>
} .V6-(d
E&
36H
privatestaticboolean hasNextPage(int currentPage, A CNfS9M_w
[AEBF2OIv
int totalPage){ TY;U2.Ud
return currentPage == totalPage || totalPage == NCA{H^CL
@D`zKYwX1
0 ? false : true; i`%.
} N$?cX(|7
!Q-wdzsp?
V9x8R
} e1
*__'
zvv:dC/p<
)He#K+[}^4
fm1X1T .
dw@E)
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]8 U ~Iy
]0c Pml
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 KiLvI,9y
z)F#u:t
做法如下: `NwdbKX
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 juToO
w5]"ga>Y
的信息,和一个结果集List: Tc
ZnmN
java代码: w'Z!;4E0
7x.%hRk
pt:;9hA
/*Created on 2005-6-13*/ !^U6Z@&/R
package com.adt.bo; {j(4m
X7aXxPCq1
import java.util.List; 6(56,i<#/
& %}/AoU
import org.flyware.util.page.Page; TW`mxj_J2
g jG2
/** mp`PE=
* @author Joa O{KB0"s>i
*/ <Mgf]v.QS
publicclass Result { ~] =?b)B
((3t:
private Page page; t\5c@j p
~
}KzJiL
private List content; %u]6KrG18b
#t71U a
/** rFag@Z"["
* The default constructor #!!AbuhzK{
*/ <4F7@q,V
public Result(){ ;:#U6?=t
super(); 3\!F\tqD \
} oo'w-\2]p
#-x@"+z
/** KvFR8s
* The constructor using fields *d*oS7
* |i)lh_iN
* @param page 5 Rz/Ri\c=
* @param content <A~GW
'HB
*/ e&J3N
public Result(Page page, List content){ 9$tl00
this.page = page; N2~$rpU3
this.content = content; cIw
eBDl
} ;bHfn-X
hjY0w
/** x72G^`Wv
* @return Returns the content. ?M&4pO&Y
*/ OCx5/ 88X
publicList getContent(){ ~"mj;5Id
return content; 0M!0JJy#*
} Vq}r_#!Q
eOrYa3hQ
/** QP\yaPE
* @return Returns the page. \.>.c g
*/ g37q/nEv
public Page getPage(){ G*\sdBW!k
return page; _'JRo%{xGX
} iPU% /_>
?iln<%G
/** @%B4;c
* @param content qyv"Wb6+
* The content to set. 6+%-GgPf
*/ %_tk7x
public void setContent(List content){ X(GV6mJ4
this.content = content; q:yO92Ow
} Xu]h$%W
1pCkWe
/** 7zI5PGWw
* @param page V<-htV
* The page to set. *-z4 <LAa
*/ p37|zX
publicvoid setPage(Page page){ ^gm>!-Gx
this.page = page; A7'b Nd6f9
} 3i(J on/p
} uu3M{*}
i`~~+6`J
+ zDc
Yq0# #__
X8b#[40:
2. 编写业务逻辑接口,并实现它(UserManager, {bTeAfbf]
n#>5?W
UserManagerImpl) ;C_ >
java代码: *aG"+c6|
*:#Z+7x
]
Qu}N:P9l?X
/*Created on 2005-7-15*/ h2&y<Eg >
package com.adt.service; Vi,Y@+4
Y`]rj-8f0B
import net.sf.hibernate.HibernateException; ,eK2I Ao
q2Rf@nt
import org.flyware.util.page.Page; $`Rxn*}V4#
#7C6yXb%
import com.adt.bo.Result; VKf6|ae
BvI 0v:
/** CXa Ld7nMX
* @author Joa sy.:T]ZH
*/ cKpQr7]ur
publicinterface UserManager { AY@k-4
5Jd`
^U
public Result listUser(Page page)throws kd`YSkZ
EP0a1.C
HibernateException; OequU'j
)]}$
} >Qk97we'9
ER2V*,n@
7V/Zr
?1$\pq^
HSql)iT
java代码: &z QWIv
l]u7.~b
Cn/q=
/*Created on 2005-7-15*/ 7yUvL8p-
package com.adt.service.impl; xZg7Jg
[U']kt
import java.util.List; bQpoXs0w;
#8E?^d
import net.sf.hibernate.HibernateException; Hi7G/2t@`
8'%+G
import org.flyware.util.page.Page; "Y(%oJS]D
import org.flyware.util.page.PageUtil; ]]3Q*bq4
q!@c_o
import com.adt.bo.Result;
T"B8;|
import com.adt.dao.UserDAO; sOC|
B
import com.adt.exception.ObjectNotFoundException; p Mh++H]"
import com.adt.service.UserManager; )=Y-f?o!
G
"c/a8
/** R{ 4u|A?9
* @author Joa T#/ 11M$uQ
*/ g!\QIv1D
publicclass UserManagerImpl implements UserManager { W7T"d4
_&=9 Ke
private UserDAO userDAO; BMF3XcH~G
X)y*#U
/** MKe *f%
* @param userDAO The userDAO to set. I'P.K| "R
*/ 4(;20(q]
publicvoid setUserDAO(UserDAO userDAO){ CCy.
this.userDAO = userDAO; wV?[3bEhM
} + f 6}p
vo.EM1x
/* (non-Javadoc) hOV_Oqe4?
* @see com.adt.service.UserManager#listUser 1k`|[l^
<%(f9j
(org.flyware.util.page.Page) 7%X+O8
*/ fA;x{0CAMX
public Result listUser(Page page)throws m9uUDq#GJ
tPA"lBS !
HibernateException, ObjectNotFoundException { oX2r?.j#M
int totalRecords = userDAO.getUserCount(); )y5iH){!
if(totalRecords == 0) FmR\`yY_,
throw new ObjectNotFoundException lej^gxj/2
_5Bu [I
("userNotExist"); <)"iL4 kDI
page = PageUtil.createPage(page, totalRecords); )~G8 L Z
List users = userDAO.getUserByPage(page); NCp%sGBmG
returnnew Result(page, users); OfW%&LAMQ
} ~LSy7$rz
YqkA&qL]#;
} @RQ+JYQi
.!9Vt#
"hz>{oe
i^~sn `o
v)TUg0U=,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e-1;dX HL
g+VRT,r
询,接下来编写UserDAO的代码: +~@7"
|d
3. UserDAO 和 UserDAOImpl: tYF$#Nor#k
java代码: EwC5[bRjUp
}`?7\\6
IwOfZuS
/*Created on 2005-7-15*/ #V,LNX)
package com.adt.dao; 9{T 8M
E`U&Z
import java.util.List; tvv[$b&
rGGS]^
import org.flyware.util.page.Page;
uT#Acg
oXvdR(Sb^
import net.sf.hibernate.HibernateException; ik8|9m4/
3{6ps : w
/** o$*bm6o
* @author Joa Q=dw 6
*/ Au~+Zz|mQ
publicinterface UserDAO extends BaseDAO { A3m{jbh
q|?`Gsr
publicList getUserByName(String name)throws LNWqgIq
{H/8#y4qp&
HibernateException; V}j%gy`
"tEj`eR
publicint getUserCount()throws HibernateException; \z&03@Sw
J{aQ1)
publicList getUserByPage(Page page)throws tvGg@Xs\
hqdC9?\
HibernateException; 't||F1X~J
>|y>e{P
} ,ZsYXW
7g {g}
Cij$GYkv
>aNbp
|k/`WC6As.
java代码: }x{rTEq
]t8{)r
JI28O8
/*Created on 2005-7-15*/ {Q}!NkF1
package com.adt.dao.impl; "FD<^
_Ac/i r[,:
import java.util.List; WK/b=p|#o
f>.`xC{
import org.flyware.util.page.Page; !3O,DhH>MC
/F\>Z]
import net.sf.hibernate.HibernateException; ){?mKB5
import net.sf.hibernate.Query; u?LW+o
"H
wVK
import com.adt.dao.UserDAO; BT
y]!%r'
v4nvZ6
/** 0(Yh~{
* @author Joa oAIY=z
*/ *93l${'
public class UserDAOImpl extends BaseDAOHibernateImpl Tw`F?i~
H8(0.IR
implements UserDAO { we6+2
(CKhY~,/u
/* (non-Javadoc) Vu_7uSp,)
* @see com.adt.dao.UserDAO#getUserByName My'9S2Y8nv
^K1~eb*K
(java.lang.String) :HQ8M*o
*/ +H2m<
publicList getUserByName(String name)throws xMO[3D&D
g] 7{5
HibernateException { /y+;g{
String querySentence = "FROM user in class vWPM:1A
r&H=i
com.adt.po.User WHERE user.name=:name"; 60Xl.
Query query = getSession().createQuery [qO5~E`;
2ID*U d*
(querySentence); $9LGdKZ_D
query.setParameter("name", name); B;Q`vKY
return query.list(); yoq\9* ?u^
} YD0vfwh
%RfY`n
/* (non-Javadoc) P>yG/:W;
* @see com.adt.dao.UserDAO#getUserCount() Zi2Eu4p l{
*/ =H.<"7
publicint getUserCount()throws HibernateException { E< io^
int count = 0; Mo:!jS~a(Z
String querySentence = "SELECT count(*) FROM E-BOIy,
0XBBA0tq
user in class com.adt.po.User"; E.zYi7YUKK
Query query = getSession().createQuery XZUB*P}]D
d=xI
(querySentence); ;L\!g%a
count = ((Integer)query.iterate().next {Oc?C:aI=
T_5*iwI
()).intValue(); ~#IWM+I
return count; "G i+zkVm
} |g: '')>[
X-*KQ+?
/* (non-Javadoc) {Kq*5Aq8
* @see com.adt.dao.UserDAO#getUserByPage mTrI""Jsu;
=DmPPl{
(org.flyware.util.page.Page) (IO\+
*/ LXTipWKz
publicList getUserByPage(Page page)throws ZYl-p]\*y
6I5[^fv45G
HibernateException { )Ta]6
String querySentence = "FROM user in class ^-csi
/:*R -VdF
com.adt.po.User"; n##w[7B*
Query query = getSession().createQuery "W,"qFx
?h>%Ix
(querySentence); .5Z,SGBf
query.setFirstResult(page.getBeginIndex()) nkr,
.setMaxResults(page.getEveryPage()); OW[/%U>
return query.list(); 0s+rd&
} 8`rAE_n`%
)M|O;~q
} ^Xt]wl*]+
H;b'"./
`0n 7Cyed
]6i_d
Wj
至此,一个完整的分页程序完成。前台的只需要调用 E:dT_x<Y
#Kb)>gzT
userManager.listUser(page)即可得到一个Page对象和结果集对象 I2Or&
_
7DHT)9lD/
的综合体,而传入的参数page对象则可以由前台传入,如果用 Hjo:;s
RJ`/qXL
webwork,甚至可以直接在配置文件中指定。 ]ukj]m/@
JJbM)B@-
下面给出一个webwork调用示例: :`Zl\!]E`o
java代码: $+)x)1
am$-sh72
=`7)X\i@z
/*Created on 2005-6-17*/ C7fi1~
package com.adt.action.user; !kHyLEV
,pGCgOG#}c
import java.util.List; u1pYlu9IW
s6eq?1l3
import org.apache.commons.logging.Log; B 3,ig9
import org.apache.commons.logging.LogFactory; Fm[?@Z&wP
import org.flyware.util.page.Page; Vqv2F @.
DY+8m8!4H
import com.adt.bo.Result; e)
/u>I
import com.adt.service.UserService; !z4Hj{A_
import com.opensymphony.xwork.Action; -c<1H)W
rTH[?mkf4
/** ?XTg%U
* @author Joa |]2eGrGj4
*/ 3Oig/KZ
publicclass ListUser implementsAction{ Yf2+@E
vI:bl~
privatestaticfinal Log logger = LogFactory.getLog ,{mf+ 3&$,
w3]0
!)t1
(ListUser.class); u_/OTy
'mY,>#sT
private UserService userService; {]/Jk07
Q,M/R6i-
private Page page; 2dV\=vd
83 ^,'Z
privateList users; "=Fn.r4I
U~zN*2-
/* Pi]s<3PL
* (non-Javadoc) WY.\<$7
* scPq\Qd?O
* @see com.opensymphony.xwork.Action#execute() %&Q7;?
*/ DHu jpZXQ
publicString execute()throwsException{ E*!zJ,@8
Result result = userService.listUser(page); *IO;`k q,;
page = result.getPage(); k
@/SeE
users = result.getContent(); Wp9
2sm+
return SUCCESS; .5Z@5g`
} 3vGaT4TDx
U*+!w@
.
/** |@bNd7=2d
* @return Returns the page. ,aj+mlZd2
*/ %>z8:oJ
public Page getPage(){ mLxwJ
return page; r@@eC['
} %[bO\,
%RD7=Z-z
/** J/&*OC
* @return Returns the users. E,yzy[gl
*/ O t4+VbB6
publicList getUsers(){ 0|+hm^'_
return users; :M?')
} !&:W1Jkp(
O
|I:[S},
/** m&jt[
* @param page q
]R @:a/
* The page to set. 17[t_T&Ak9
*/ M0IqQM57N
publicvoid setPage(Page page){ X|n[9h:%
this.page = page; VFaK>gQ
} [@?.}!
h*X%:UbW
/** . eag84_
* @param users eRqexqO!
* The users to set. rxK[CDM,
*/ d~f0]O
publicvoid setUsers(List users){ 9qO:K79|
this.users = users; rpP+20 v
} 0~L8yMM
U!UX"r
/** qxCL
* @param userService 2d J)4
* The userService to set. `r0
qn'*
*/ n7!Lwq2
publicvoid setUserService(UserService userService){ lJQl$Wx^
this.userService = userService; 7)It1i-
} &\D<n;3
} Sw9mrhzJfe
G;#t6bk
IhKas4
+z?f,`.*
.$}zw|,q
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, FZ.Yn
!rmo*-=^=
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 T[9jTO?W2
2i'-lM=
么只需要: btz3f9
java代码: +O:pZz
+#"Ic:
(V%vFD1)
<?xml version="1.0"?> X!HSS/'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^>}[[:( 6/
[67f; ?b
1.0//EN" "http://www.opensymphony.com/xwork/xwork- hr"+0KeX
ZjbG&oc
1.0.dtd"> XlcDF|?{.
Evgq}3
<xwork> 0JL6EL>_
k.f:nv5JO
<package name="user" extends="webwork- iP\&fZY_
I8wVvs;k
interceptors"> E6\~/=X=%
[?o vJ
<!-- The default interceptor stack name {'bkU9+
TZ_'nB~
--> *1]k&#s
<default-interceptor-ref _[Wrd?Z
6D]G*gwk[
name="myDefaultWebStack"/> /faP]J)
:v ~q
<action name="listUser" ~l(tl[
B9Tztg
class="com.adt.action.user.ListUser"> \B+SzW
<param wq`Kyhk
1ORi]`
name="page.everyPage">10</param> Q"_T040B
<result ,'DrFlI
kF~e3A7C
name="success">/user/user_list.jsp</result> :rc[j@|pH
</action> ~a,'
]* Ki7h|B
</package> 1MFpuPJk
| (9FV^_
</xwork> $ aBSr1
6HQwL\r79
A{T@O5ucj
m|gd9m$,?
D??/=`|8
dp W%LXM_
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 UC$+&&rO
n,LKkOG
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。 ]KT,s].
[:'?}p
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 p arG
J~`%Nj5>
$F$R4?_
@n'ss!h
YQsc(6
我写的一个用于分页的类,用了泛型了,hoho Y|jesa {x
`;GGuJb \
java代码: Upen/1 bA
m3e49 bP
LZ: \V)5+
package com.intokr.util; T<GD !j(
7OHw/-j\
import java.util.List; nOzTHg8
[)c|oh%
/** 84cH|j`w
* 用于分页的类<br> 4u7>NQUDu
* 可以用于传递查询的结果也可以用于传送查询的参数<br> nL~
b
* m(]IxI
* @version 0.01 Ka2tr]+s
* @author cheng SXF_)1QO\W
*/
!}48;P l
public class Paginator<E> { /a)=B)NH
privateint count = 0; // 总记录数 ay[*b_f
privateint p = 1; // 页编号 GQWTQIl]
privateint num = 20; // 每页的记录数 d'D\#+%>=
privateList<E> results = null; // 结果 ?"u-@E[m
A2S9h,t
/** S*:w\nXP~
* 结果总数
>ON.ftZi
*/ &$im^0`r_
publicint getCount(){ :N:8O^D^<
return count; )S?}huX
} (LPD
S`.-D+.68
publicvoid setCount(int count){ F\72^,0
this.count = count; IQv>{h}
} F'*4:WD7
- mXr6R?
/** {mGWMv
* 本结果所在的页码,从1开始 VHNiTp
* }Cf[nGh|B
* @return Returns the pageNo. M lwQ_5O
*/ !-~(*tn
publicint getP(){ [GM<Wt0
return p; ^q2zqC
} ywte\}
ZeV)/g,w
/** P://Zi6>
* if(p<=0) p=1 S45_-aE
* ,BAF?}04=
* @param p Z8UM0B=i
*/ @kymL8"2w
publicvoid setP(int p){ v:;cTX=x`#
if(p <= 0) 5!*a,$S
p = 1; q>X2=&1
this.p = p; D3ad2vH
} *h6i9V%'
1A`";E&
/** 49GCj`As
* 每页记录数量 ?>&Zm$5V
*/ s6uAF(4,
publicint getNum(){ Cn '=_1p
return num; U 7?ez
} pXa? Q@6
N3) v,S-
/** ~G:7*:[b
* if(num<1) num=1 cw{[B%vw
*/ Y?cw9uYB
publicvoid setNum(int num){ |&vuK9q
if(num < 1) o5R40["
num = 1; Xi.?9J`@
this.num = num; YvX I
} gZv<_0N
Hc9pWr"N
/** EVsZ:Ra^k
* 获得总页数 t;3.;
*/ Y[4B{
publicint getPageNum(){ g (k|"g`*
return(count - 1) / num + 1; RUKSGj_NJ
} FO$Tn+\ 6
-&}E:zoe
/** OFv} jT
* 获得本页的开始编号,为 (p-1)*num+1 566Qikw2
*/ lfP|+=^B
publicint getStart(){ pkx>6(Y
return(p - 1) * num + 1; vKf=t&gqr
} IIkJ"Qg.
f'dI"o&^/d
/** Km7
* @return Returns the results. $(U|JR@
*/ wn&2-m*a
publicList<E> getResults(){ mZyTo/\0
return results; wQT'~'kL
} 6*7&X#gG
q0wVV
public void setResults(List<E> results){ (6nw8vQ
this.results = results; HenJlo
} ~@lNBF
X[<9+Q-&
public String toString(){ at!?"u
StringBuilder buff = new StringBuilder :F&WlU$L
)w-?|2-w5
(); CCV~nf
buff.append("{"); C#>C59
buff.append("count:").append(count); tUQ)q
buff.append(",p:").append(p); d/1XL[&
buff.append(",nump:").append(num); s9iM hCu|
buff.append(",results:").append \BL9}5y
@#apOoVW>
(results); SCij5il%
buff.append("}"); VzesqVx
return buff.toString(); 5oS\uX|
} o6 /?WR 9
VM[8w`
} @d\F; o<
"|if<hx+
3nO|A: t