Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qQ^d9EK'?~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0HqPyM13Q
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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 +A@m9
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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 C
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分页支持类: iHPUmTus--
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java代码: ~p:?QB>1]
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package com.javaeye.common.util; kd yAl,
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}
import java.util.List; a0PE^U
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publicclass PaginationSupport { xk& NAB
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publicfinalstaticint PAGESIZE = 30; _6ZzuVv3/
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privateint pageSize = PAGESIZE; .46#`4av
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privateList items; }MP>]8Aq
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privateint totalCount; _BbvhWN&+
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privateint[] indexes = newint[0]; P$_&
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privateint startIndex = 0; 09'oz*v{#
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public PaginationSupport(List items, int H9U.lb
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totalCount){ @Gt`Ds9=
setPageSize(PAGESIZE); Or7
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setTotalCount(totalCount); GF*>~_Yr
setItems(items); @o6R[5(
setStartIndex(0); {?Od{d9
} pr_>b`p6
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public PaginationSupport(List items, int nob0T5G
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totalCount, int startIndex){ j
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setPageSize(PAGESIZE); 5MR,UgT
setTotalCount(totalCount); qw<HY$3=
setItems(items); /&r|ec5
setStartIndex(startIndex); TN\|fzj
} R:M,tL-l
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public PaginationSupport(List items, int nBkh:5E5%
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totalCount, int pageSize, int startIndex){ Ke!'gohv
setPageSize(pageSize); X3',vey
setTotalCount(totalCount); A|L'ih/
setItems(items); iPvuz7j=h
setStartIndex(startIndex); V^TbP.
} 7VAJJv3
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publicList getItems(){ 22&;jpL'?
return items; lj4o#^lC
} py
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publicvoid setItems(List items){ E"6X|I n
this.items = items; ! \sMR
} wksl0:BL
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publicint getPageSize(){ 19W:-Om
return pageSize; Y]Vq\]m\
} BRzfic:e
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publicvoid setPageSize(int pageSize){ "j^MB)YD
this.pageSize = pageSize; ]A^4}CK^<
} "hQgLG
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publicint getTotalCount(){ T]9m:zX9s
return totalCount; [ *>AN7W
} [c~kF+8
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publicvoid setTotalCount(int totalCount){ 9AQxNbs
if(totalCount > 0){ =n+ \\D
this.totalCount = totalCount; eTbg7"waA
int count = totalCount / mV)+qXC
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pageSize; /<{: I \<
if(totalCount % pageSize > 0) ]JXKZV8$0
count++; [M%._u,
indexes = newint[count]; dg_G s>?2
for(int i = 0; i < count; i++){ > 'i
indexes = pageSize * A6!F@Ic[
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} ?6"{!s{v
}else{ %\Wf^6Y^
this.totalCount = 0; -oP'4QVb
} ]rN#B-aAr
} R[jEvyD>(
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publicint[] getIndexes(){ ?!'ZfQ:zK
return indexes; iM]o"qOQm
} Nd@~>&F
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publicvoid setIndexes(int[] indexes){ (Un_!)
this.indexes = indexes; ,r8Tbk]m
} F(,UA+$A
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publicint getStartIndex(){ ;j%BK(5
return startIndex; 2=iH$v
} Vzl^Ka'
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publicvoid setStartIndex(int startIndex){ t0)<$At6J
if(totalCount <= 0) !?!C'-ps
this.startIndex = 0; .@ F]Pht
elseif(startIndex >= totalCount) <RNJ>>0
this.startIndex = indexes T~:|!`
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[indexes.length - 1]; O"G >wv
elseif(startIndex < 0) rXfy!rD_P_
this.startIndex = 0; bm% $86
else{ }"^'%C8EX
this.startIndex = indexes 9DQa
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[7FItlF%I
[startIndex / pageSize]; %w7pkh,
} p< "3&HA
} eKvV*[Na
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publicint getNextIndex(){ CQh,~
int nextIndex = getStartIndex() + A:l@_*C..
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pageSize; ^BQrbY
if(nextIndex >= totalCount) P
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return getStartIndex(); ^vilgg~
else rl2&^N
return nextIndex; :GpDg
} UMl#D>:C<
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publicint getPreviousIndex(){ $37
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int previousIndex = getStartIndex() - %ru;;h
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pageSize;
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if(previousIndex < 0) rgmF: C
return0; c(;a=n(E#
else DwHF[]v'
return previousIndex; YuZ"s55zU{
} N-
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} 3"n\8#X{
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抽象业务类 n_ lo`
java代码: &e-U5'(6v_
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/** LI2&&Mw
* Created on 2005-7-12 JM1R ;i6
*/ D%6;^^WyUx
package com.javaeye.common.business; GaX[C<Wt
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import java.io.Serializable; HK|ynBAo
import java.util.List; $`R6=\|
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import org.hibernate.Criteria; PxH72hBS
import org.hibernate.HibernateException; D?XM,l+
import org.hibernate.Session; JRo?s~Ih
import org.hibernate.criterion.DetachedCriteria; FFdBtB
import org.hibernate.criterion.Projections; b4^`DHRu6
import ;q N+^;,2
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org.springframework.orm.hibernate3.HibernateCallback; M@0;B30L
import )jrV#/m9
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org.springframework.orm.hibernate3.support.HibernateDaoS g~(E>6Y
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upport; jReXyRmo({
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import com.javaeye.common.util.PaginationSupport; u#}[ZoI
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public abstract class AbstractManager extends F 8B#}%JE
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HibernateDaoSupport { ,U(1NK8o
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privateboolean cacheQueries = false; Jgnhn>dHe
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privateString queryCacheRegion; a!O0,y
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publicvoid setCacheQueries(boolean 8Q_SRwN
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cacheQueries){ p<M\U"5Ye
this.cacheQueries = cacheQueries; Y>'|oygHA
} cM&{+el
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publicvoid setQueryCacheRegion(String EkziAON
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queryCacheRegion){ $56,$K`H
this.queryCacheRegion = xyI}y(CN1
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queryCacheRegion; As>_J=8} 3
} ?lP':'P
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publicvoid save(finalObject entity){ %2v4<icvq
getHibernateTemplate().save(entity); ,\NFt`]j
} y*X_T,K8
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publicvoid persist(finalObject entity){ )ZN|t?|
getHibernateTemplate().save(entity); qvPtyc^fN
} M![J2=
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publicvoid update(finalObject entity){ 720D V+o
getHibernateTemplate().update(entity); R?]02Q
} `]%|f
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publicvoid delete(finalObject entity){ %f]:I
getHibernateTemplate().delete(entity); <_7*67{
} P'_H/r/#
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publicObject load(finalClass entity, AJ=qn a
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finalSerializable id){ +llR204
return getHibernateTemplate().load !jTcsN%
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(entity, id); 8SGo9[U2
} &G-!qxe
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publicObject get(finalClass entity, _fKou2$yz
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finalSerializable id){ i*Z"Me
return getHibernateTemplate().get -PfX0y9n
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(entity, id); 6ZP"p<xX
} Q637N|01
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publicList findAll(finalClass entity){ `7r@a
return getHibernateTemplate().find("from maNl^i
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" + entity.getName()); r [*Vqcz
} <_-hRbS
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publicList findByNamedQuery(finalString Rd#WMo2Xd
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namedQuery){ Ys\Wj%6A
return getHibernateTemplate Rx}$0c0
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().findByNamedQuery(namedQuery); ~GZY 5HF
} ):[7E(F=
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publicList findByNamedQuery(finalString query, :0Rx#%u}#
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finalObject parameter){ uo@n(>}EL
return getHibernateTemplate vwxXgk
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().findByNamedQuery(query, parameter); ;;#qmGoE
} )% ~OH
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publicList findByNamedQuery(finalString query, Tu).K.p:
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finalObject[] parameters){ oY933i@l)P
return getHibernateTemplate v]B3m
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().findByNamedQuery(query, parameters); kH
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} Q$zO83
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publicList find(finalString query){ (pv+c,
return getHibernateTemplate().find e4 >_v('
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(query); 8@MV%MVy$
} xLK<W"%0
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publicList find(finalString query, finalObject ,F,X
,
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parameter){ 5\]Sv]s)R
return getHibernateTemplate().find xdp`<POn%
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(query, parameter); 6\g cFfo
} 7$CBx/X50)
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public PaginationSupport findPageByCriteria 5kCUaPu
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(final DetachedCriteria detachedCriteria){ 6WXRP;!Q
return findPageByCriteria b4[bL2J$h1
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y^$X*U/q%U
} W*Zkc:{eB
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public PaginationSupport findPageByCriteria : y%d
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(final DetachedCriteria detachedCriteria, finalint S[PE$tYT#t
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startIndex){ DtXrWS/
return findPageByCriteria #49kjv@
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(detachedCriteria, PaginationSupport.PAGESIZE, 3G}x;Cp\D
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startIndex); *U&0<{|T
} :~Wrf8UQ
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public PaginationSupport findPageByCriteria ywGd> @
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(final DetachedCriteria detachedCriteria, finalint }dgfqq
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pageSize, Oo5w?+t
finalint startIndex){ `6~Aoe
return(PaginationSupport) }$SavB#SBP
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getHibernateTemplate().execute(new HibernateCallback(){ ,,%i;
publicObject doInHibernate gQ Fjr_IS#
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(Session session)throws HibernateException { Xg|B \\
Criteria criteria = J:CXW%\ <q
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detachedCriteria.getExecutableCriteria(session); I>]oS(GNT
int totalCount = [>8}J"
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((Integer) criteria.setProjection(Projections.rowCount Z}mLLf E
3x{t(
()).uniqueResult()).intValue(); KL1/^1
criteria.setProjection !t$'AoVBq
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(null); EofymAi%
List items = \<JSkr[h!"
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criteria.setFirstResult(startIndex).setMaxResults 52:HNA\E/
R!\_rc1/
(pageSize).list(); v1o#1;
PaginationSupport ps = _=_Px@<Q
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new PaginationSupport(items, totalCount, pageSize, b6nsg|
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startIndex); Ktb\ b w
return ps; >`Y.+4mE
} ^Cu\VV
}, true); Aw$x;3y
} IUE~_7
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public List findAllByCriteria(final -+(jq>t
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DetachedCriteria detachedCriteria){ ALrw\qV
return(List) getHibernateTemplate }\tdcTMgS
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().execute(new HibernateCallback(){ [ey:e6,T9
publicObject doInHibernate |'P]GK
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(Session session)throws HibernateException { 4r>6G/b8*
Criteria criteria = 8ja$g,
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detachedCriteria.getExecutableCriteria(session); k;K)xb[w |
return criteria.list(); Sj]T
} _"?.!
}, true); 6G1@smP
} v\KA'PmiP
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public int getCountByCriteria(final -G}[AkmS
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DetachedCriteria detachedCriteria){ 6IBgt!=,
Integer count = (Integer) Yw4n-0g
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getHibernateTemplate().execute(new HibernateCallback(){ t[ubn+
publicObject doInHibernate tNO-e|~'
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(Session session)throws HibernateException { M2PAy! J
Criteria criteria = `NCwK6/i
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detachedCriteria.getExecutableCriteria(session); fsJ9bQm/
return U{7w#>V
.
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criteria.setProjection(Projections.rowCount 10)jsA
Bp_$.!Qy
()).uniqueResult(); }YB*]<]
} :o|\"3
}, true); \w/yF4,3<w
return count.intValue(); `IP/d
} +ln9c
} ^V ?<K.F
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用户在web层构造查询条件detachedCriteria,和可选的 R n}l6kbM
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *,e:]!*
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PaginationSupport的实例ps。 zz+$=(T:M
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ps.getItems()得到已分页好的结果集 -m)X]]~C
ps.getIndexes()得到分页索引的数组 pOGeruu?
ps.getTotalCount()得到总结果数 v=0(~<7B
ps.getStartIndex()当前分页索引 6g|*`x{
ps.getNextIndex()下一页索引 `bFff%_
ps.getPreviousIndex()上一页索引 I KqQ>Z-q~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ti5mIW\
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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 2Z-ljD&
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一下代码重构了。 O~T@rX9f
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我把原本我的做法也提供出来供大家讨论吧: /M|262%
kjg~n9#T
首先,为了实现分页查询,我封装了一个Page类: 4 8:>NW
java代码: wLi4G@jJ
3 jGWkby0
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/*Created on 2005-4-14*/ gbI^2=YT'
package org.flyware.util.page; mkYqpD7
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/** hWM<
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* @author Joa mtJ9nC
* '?!zG{x
*/ ~k!j+>yT
publicclass Page { 4,sJE2"[9
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/** imply if the page has previous page */ Q3
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privateboolean hasPrePage; w\(.3W7
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/** imply if the page has next page */ ABQa 3{v
privateboolean hasNextPage; OjFLPGRCh
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/** the number of every page */ +aJ>rR
privateint everyPage; x.f]1S7h[
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/** the total page number */ Rtb7|
privateint totalPage; K@sV\"U(*E
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/** the number of current page */ }@;ep&b*
privateint currentPage; UELy"z
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/** the begin index of the records by the current >64P6P;S
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query */ qCljo5Tq'
privateint beginIndex; U@HK+C"M|
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/** The default constructor */ v{(^1cX
public Page(){ 7uKNd
*%
{ &"CH]r
} X#*JWQO=
N"" BCh"
/** construct the page by everyPage N.\-
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* @param everyPage {>R:vH8
* */ *]AdUEV?
public Page(int everyPage){ - db_E#
this.everyPage = everyPage; P+s!|7'
} P*
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/** The whole constructor */ K%a%a6k`
public Page(boolean hasPrePage, boolean hasNextPage, t/cY=Wp
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int everyPage, int totalPage, =<{np
int currentPage, int beginIndex){ )+[ gd/<C.
this.hasPrePage = hasPrePage; {4G%:09~J
this.hasNextPage = hasNextPage; =h0,?]z
this.everyPage = everyPage; <~6h|F8
this.totalPage = totalPage; )Qe~8u@?
this.currentPage = currentPage; ;nodjbr,j
this.beginIndex = beginIndex; tKuVQH~D
} yKa{08X:
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/** EK;YiJ
* @return
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* Returns the beginIndex. cd(GvX'
*/ H,DM1Z9rz
publicint getBeginIndex(){ ~F4fFQ-yy
return beginIndex; E~]R2!9
} 9fhsIe
pi
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/** MCS8y+QK
* @param beginIndex ;D:9+E<>a
* The beginIndex to set. 7*
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*/ 4)@mSSfn.
publicvoid setBeginIndex(int beginIndex){ WU
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this.beginIndex = beginIndex; X$ s:>[H
} t=Xv;=daB
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/** E%rk[wI
* @return ;$smH=I
* Returns the currentPage. d8[J@M53|T
*/ L1cI`9
publicint getCurrentPage(){ ZUoxMm
return currentPage; X~lVVBO
} :-/M?,Q"
t.7?
/** \/: {)T~
* @param currentPage k< y>)
* The currentPage to set. N"]q='t
*/ .NYbi@bk(<
publicvoid setCurrentPage(int currentPage){ -I&m:A$4*
this.currentPage = currentPage; )%`^xR
} fA+,TEB~d
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/** fh](K'P#^
* @return p-Kz-+A [
* Returns the everyPage. / c AUl
*/ ti
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publicint getEveryPage(){ M luVx'
return everyPage; : cF[(i/k4
} /atW8 `&
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/** /ro=?QYb
* @param everyPage m9.{[K"
* The everyPage to set. n ~shK<!C
*/ -'t)=YJ
publicvoid setEveryPage(int everyPage){ "Y~:|?(@-
this.everyPage = everyPage; >'&p>Ad)
} (oEC6F
n=y[CKS
/** %-c*C $
* @return hw=
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* Returns the hasNextPage. 3HcQ(+Z
*/ nlW +.a[
publicboolean getHasNextPage(){ Zc
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return hasNextPage; j2QmxTa!
} /SrCElabP
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/** ?u "
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* @param hasNextPage mF,Y?ax
* The hasNextPage to set. zi]\<?\X
*/ &Low/Y'.jJ
publicvoid setHasNextPage(boolean hasNextPage){ |}(`kW
this.hasNextPage = hasNextPage; FaDjLo2'o
} '}B+r@YCN
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/** mi,E-
* @return G!>z;5KuS
* Returns the hasPrePage. e\!0<d
*/ t!r A%*
publicboolean getHasPrePage(){ j4|N-:
return hasPrePage; Kx;eaz:gx
} eHn7iuS8
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/** __|+w<]
* @param hasPrePage +trC,D
* The hasPrePage to set. +
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*/ i36eBjT
publicvoid setHasPrePage(boolean hasPrePage){ SL#0kc0x
this.hasPrePage = hasPrePage; hc>HQrd
} <{V(.=11
mID"^NOi#
/** 3?V_BUoON
* @return Returns the totalPage. c'%-jG)\
* SYCEQ5
-
*/ _B/dWA,P
publicint getTotalPage(){ >z%&xgOa
return totalPage; ]n_
k`
} psg)*'r
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/** ]:4*L
* @param totalPage Ju96#v+:
* The totalPage to set. @~!wDDS
*/ 8FKXSqhVM
publicvoid setTotalPage(int totalPage){ zgNc4B
this.totalPage = totalPage; zNxW'?0Z?
} c:<005\Bg
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} "B3N*R(["
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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 9Uj$K>:
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个PageUtil,负责对Page对象进行构造: 3I)VHMC
java代码: D~hg$XzK
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* w?N{.
/*Created on 2005-4-14*/
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package org.flyware.util.page; jQ2Ot <
gtk7)Uh
import org.apache.commons.logging.Log; x=b7': nQ
import org.apache.commons.logging.LogFactory; 5*l T.
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/** )Im#dVQs=
* @author Joa F`gi_;c
* *=]&&<
*/ ^(vs.U^U<
publicclass PageUtil { Gft%Mq
v
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privatestaticfinal Log logger = LogFactory.getLog +jS|2d
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(PageUtil.class); 6$kq aS##
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/** r^FhTzA=1
* Use the origin page to create a new page [fAV5U
* @param page GFeQ%l`7F
* @param totalRecords :~2vJzp@?
* @return 2% L LSa
*/ YB(Q\hT~\;
publicstatic Page createPage(Page page, int p1Jh0o8
ar__ Pf6r
totalRecords){ Jm xH"7hTE
return createPage(page.getEveryPage(), B8": 2HrW$
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page.getCurrentPage(), totalRecords); N5Q[n d
} =/s>Q l
s/$?^qtyC
/** qh9Z50E9
* the basic page utils not including exception ~Sj9GxTe
sDPs
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handler |TS>hwkI
* @param everyPage '[AlhBX
* @param currentPage w>pq+og&
* @param totalRecords ED=V8';D
* @return page XGYbnZ~
*/ RL!Oi|8
publicstatic Page createPage(int everyPage, int 9s\A\$("l
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currentPage, int totalRecords){ L2\#w<d
everyPage = getEveryPage(everyPage); ]V^iN=(_5
currentPage = getCurrentPage(currentPage); Xe$ I7iKD
int beginIndex = getBeginIndex(everyPage, RRmz"j>
ULs\+U
currentPage); ;_c;0)
int totalPage = getTotalPage(everyPage, 1oR7iD^
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totalRecords); >3p\m
boolean hasNextPage = hasNextPage(currentPage, [k.t WA,&
cpL7!>^=
totalPage); >0/i[k-dk
boolean hasPrePage = hasPrePage(currentPage); q!.byrod
)
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returnnew Page(hasPrePage, hasNextPage, ~IYUuWF(
everyPage, totalPage, - Ajo9H
currentPage, ] eotc2?u
ZGexdc%
beginIndex); wxKX{Bs
} ?qPo=~y01
SheM|I~de
privatestaticint getEveryPage(int everyPage){ .B7,j%1r
return everyPage == 0 ? 10 : everyPage; TrlZ9?3#D
} mWoAO@}Y
o}
J&E{Tk
privatestaticint getCurrentPage(int currentPage){ s^Y"' ` +
return currentPage == 0 ? 1 : currentPage; $Q &lSVQ
} K'L^;z6
r+A{JHnN
privatestaticint getBeginIndex(int everyPage, int KI)M JG:t
;O,+2VzP%^
currentPage){ 7?#J~.d5
return(currentPage - 1) * everyPage; 5x5@t
:
} #eoome2Q
/5S30 |K
privatestaticint getTotalPage(int everyPage, int uZNTHD
( /=f6^}
totalRecords){ MLXN Zd
int totalPage = 0; fT;s-v[`k
nEJq_
if(totalRecords % everyPage == 0) L{X_^
totalPage = totalRecords / everyPage; ^]H5h ]U'
else gqZ'$7So
totalPage = totalRecords / everyPage + 1 ; y&6FybIz
`95r0t0hh\
return totalPage; abuh`H#
} fY{1F
9Vg?{v!yn
privatestaticboolean hasPrePage(int currentPage){ ;y,5k?
return currentPage == 1 ? false : true; 3k\#CiB{
} g2BHHL;`
/Gd=n
privatestaticboolean hasNextPage(int currentPage, d(\%Os
sZjQ3*<-r
int totalPage){ G? ])o5
return currentPage == totalPage || totalPage == <`.X$r*
o)h_H;
0 ? false : true; QX!-B
} m,VOx7%n
=i$Fl{vH
{:Orn%Q
} ( Z619w
Yrb{ByO&
x.]i}mt
Q8T]\6)m
1#C4;3i,
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 b,5~b&<h
.8@$\ZRP
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 x6Bu F_.
YJ^]
u}
做法如下: bn#"?6Z2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Bn^0^J-
b+%f+zz*h
的信息,和一个结果集List: 3_ r*y9l
java代码: Hkk/xNP
?Y$JWEPJ
?iw!OoZ`
/*Created on 2005-6-13*/ o
m^0}$V
package com.adt.bo; A#K14Ayr
VQ(j pns5
import java.util.List; HguT"%iv
_>5(iDW0
import org.flyware.util.page.Page; Vp#JS3Y
E-4b[xNj*+
/** 6hw=
* @author Joa |ax3sAg
*/ sGi"rg#
publicclass Result { S
^"y4-2
\RNNg
private Page page; YpWPz %`:
{ME2ImD
private List content; oL!EYbFD'Z
rxe>}ZO
/** ,-$LmECg
* The default constructor ,g%0`SO
*/ D60aH!ft
public Result(){ 6w*dKInG[-
super(); x/NfZ5e0X
} O(#)m>A
&T+atL `N
/** %D UH@j
* The constructor using fields F5LuSy+v
* l>2E (Y|
* @param page $~~Jw]
* @param content p2Z?T}fa}&
*/ "An,Q82oHf
public Result(Page page, List content){ z#zI1Am(O
this.page = page; NvD7Krqwa
this.content = content; >NO[UX%yP
} D|lzGt
Y#]+Tm(+
/** g%ndvdb m
* @return Returns the content. ,MdV;j~"'
*/ m.JBOq=
publicList getContent(){ j5QuAU8
return content; .sxcCrQE
} h2)yq:87
e
h&IPU S
/** !SC`D])l
* @return Returns the page. bo,_&4?
*/ szb_*)k
public Page getPage(){ i#&z2h-b
return page; o906/5M
} xN>npP
GX)u|g
/** w~.f
* @param content wa(8Hl|Y
* The content to set. '@cANGg7[
*/ kj|6iG
public void setContent(List content){ 8|b3j^u
this.content = content; 2;[D;Y}
} teOe#*
s6ZuM/Q
/** jG6]A"pr
* @param page H ;7(}:.
* The page to set. 3T31kQv{
*/ _ftI*ni:<
publicvoid setPage(Page page){ R]Vt Y7}i,
this.page = page; G
!<Z.]
} ~Xw"}S5
} -B>++r2A^
214Ml0/%
7@#>bE6
3ovWwZ8&
];} Wfl
2. 编写业务逻辑接口,并实现它(UserManager, Q;MT"=RW
t$+?6E
UserManagerImpl) @M<|:Z %.@
java代码: \Lq h j
Y}@&h!
g(nPQOs$u
/*Created on 2005-7-15*/ 9Q
-HeXvR
package com.adt.service; 8{Q<N%Jnu
E^Y#&skXp3
import net.sf.hibernate.HibernateException; #:%&x@@c3P
{qDSPo
import org.flyware.util.page.Page; 9 ^o-EC!_
VJ84?b{c
W
import com.adt.bo.Result; pb^i^tA+A
m9)p-1y@5
/** 6f;fx}y
* @author Joa +_7*iJtD5
*/ ~)*,S^k(C.
publicinterface UserManager { `{4i)n%e&
.\K_@M
public Result listUser(Page page)throws tWo{7) Eb
_my"%@n
HibernateException; w;D+y*2
FK6[>(QO
} PEN\-*Pv
D>|H 2
E"\/M
~Xr=4V:a+
W"724fwu&
java代码: 5&xB6|k
=6xrfDbN8
O[# 27_dH
/*Created on 2005-7-15*/ d[r#-h>dS
package com.adt.service.impl; kTKq/G,Ft
01[NX? qEa
import java.util.List; :Y-{Kn6`_
dCb`xR}
import net.sf.hibernate.HibernateException; |
H!28h
Kj V:|
import org.flyware.util.page.Page; "BD~xP(
import org.flyware.util.page.PageUtil; %mL-$*
YTAmgkF\4
import com.adt.bo.Result; k")R[)92b?
import com.adt.dao.UserDAO; Z/Eb:
import com.adt.exception.ObjectNotFoundException; <wZQc
import com.adt.service.UserManager; Rn#KfI:{
7ByTnYe~S
/** (
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* @author Joa DvME1]7)
*/ ~0?mBy!-O
publicclass UserManagerImpl implements UserManager { Xsa2(-
aF8fqu\
private UserDAO userDAO; jNu9KlN
Yv
hA_v
/** "b?v?V0%C
* @param userDAO The userDAO to set. e }mD]O}
*/ U0=]
publicvoid setUserDAO(UserDAO userDAO){ U93}-){m
this.userDAO = userDAO; ygOd69
} l;af~ef)'
Xf0M:\w=M
/* (non-Javadoc) UU'|Xz9~
* @see com.adt.service.UserManager#listUser "~E[)^ANxD
,PlO8;5]
(org.flyware.util.page.Page) syk!7zfK
*/ nv)2!mAh\
public Result listUser(Page page)throws )X04K~6lY
:z}MIuf
HibernateException, ObjectNotFoundException { El<]b7
int totalRecords = userDAO.getUserCount(); Rfn9s(m
if(totalRecords == 0) l6(-I
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throw new ObjectNotFoundException h H <J,Wn
O#&c6MDB:
("userNotExist"); 0ph{
page = PageUtil.createPage(page, totalRecords); .tkT<o-u<J
List users = userDAO.getUserByPage(page);
pnMEB,)
returnnew Result(page, users); MzPzqm<
} hbU+Usx
-yR.<KnL
} y'FS/=u>0
$\b$}wy*
~jK{ ,$:=
t(GR)&>.2
pp.6Ex
(R
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6)z?f4,
ay1YOfa*
询,接下来编写UserDAO的代码: xAafm<L@!
3. UserDAO 和 UserDAOImpl: 6Z#\CixG
java代码: $f,n8]
Sa\!*e_sN
f?oa"
/*Created on 2005-7-15*/ ng:kA%!
Q
package com.adt.dao; nM\eDNK
9 Yx]=n
import java.util.List; ;WgJ<&33
0~HKiH-
import org.flyware.util.page.Page; KQcs3F@t
u4.ngjJ
import net.sf.hibernate.HibernateException; *"WDb|PBb
J\J?yo 6
/** @)-sTgn
* @author Joa aUxGzMZ
*/ Kh(ZU^{n
publicinterface UserDAO extends BaseDAO { .U"8mP=&
p>vn7;s2#
publicList getUserByName(String name)throws I96Ci2)m
!h(|\"
}
HibernateException; \(VTt|}By$
bfA=3S"0
publicint getUserCount()throws HibernateException; ,QC{3i~
XGJj3-eW{
publicList getUserByPage(Page page)throws 76wc ,+
l_EM8pL,f
HibernateException; H_EB1"C;\
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} (
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0ge$ p,
*\(r+>*x*
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6&DX] [G
java代码: i O/K nH
9Rn?
:B~W:
{n/uh0>f*
/*Created on 2005-7-15*/ ;l&4V
package com.adt.dao.impl; I/M _p^
so)"4
SEu
import java.util.List; jx.[#6e
MS>t_C(
import org.flyware.util.page.Page; rSxxH]-
{g2@6ct
import net.sf.hibernate.HibernateException; ^
"i l}8`
import net.sf.hibernate.Query; @o#!EfZyE
_9tK[/h
import com.adt.dao.UserDAO; RletL)
#Y0-BYa^
/** &ZghMq~
* @author Joa `6 /$M!4$
*/ XO-Prs
public class UserDAOImpl extends BaseDAOHibernateImpl u$*56y
fGw^:,B
implements UserDAO { B;R.# ^@/
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/* (non-Javadoc) ZiYm:$CJ
* @see com.adt.dao.UserDAO#getUserByName CPVjmRUF|
lY~4'8^
(java.lang.String) D'L'#/hK
*/ Dq36p${\W
publicList getUserByName(String name)throws P&j(,7
)+6v
HibernateException { /"
${$b{
String querySentence = "FROM user in class G P:FSprP
cTD!B% x
com.adt.po.User WHERE user.name=:name"; uC8L\UXk
Query query = getSession().createQuery CbPuoOl
K=C!b?
(querySentence); o Y1';&BO9
query.setParameter("name", name); rj6tZJZ#o0
return query.list(); Ma'_e=+A
} c9kzOQ2n
/n5F(5<
/* (non-Javadoc) %q!8={J8
* @see com.adt.dao.UserDAO#getUserCount() T[,/5J
*/ U~}
U\_
publicint getUserCount()throws HibernateException { HDda@Jy
int count = 0; {fha`i
String querySentence = "SELECT count(*) FROM pl5P2&k
Tn eq6>
user in class com.adt.po.User"; f6_];]yP
Query query = getSession().createQuery Xcrk;!IB?
pM{nh00[
(querySentence); Z.W66\8~}^
count = ((Integer)query.iterate().next s[K^9wz
Rl qQ
()).intValue(); ~by]xE1Eg
return count; UOGuqV-
} :l2g# * c
M
t*6}Cl
/* (non-Javadoc) Nru7(ag1~
* @see com.adt.dao.UserDAO#getUserByPage qw7@(R'"
DUL4noq{
(org.flyware.util.page.Page) Kx.X 7R
*/ MZpK~c1`
publicList getUserByPage(Page page)throws aM@z^<Ub
lqowG!3H
HibernateException { S#-wl2z
String querySentence = "FROM user in class N0K){
wO:Sg=,
com.adt.po.User";
U3izvM
Query query = getSession().createQuery I=7Y]w=
QV h4
(querySentence); "]m+z)lWd
query.setFirstResult(page.getBeginIndex()) Vo9F
.setMaxResults(page.getEveryPage()); dWXstb:[
return query.list(); cXR1grz
} (]RM6i7
SG?Nsp^%`B
} 7}GK%H-u
LAP6U.m'd
6ns! ~g@
kM'"4[,nz
"F3]X)}
至此,一个完整的分页程序完成。前台的只需要调用 HxBm~Lcqy
3)ma\+< 6
userManager.listUser(page)即可得到一个Page对象和结果集对象 28hHabd|
d\H&dkpH
的综合体,而传入的参数page对象则可以由前台传入,如果用 gP-nluq
zVi15P$
webwork,甚至可以直接在配置文件中指定。 ]l@ qra
q;fKcblKj
下面给出一个webwork调用示例: l"{Sm6:;-
java代码: g
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a8dXH5_
rrnNn'
/*Created on 2005-6-17*/ :qR=>n=
package com.adt.action.user; ]Ni;w]KE
`/"nTB
import java.util.List; \XF}?*8
|+:h|UIUQ
import org.apache.commons.logging.Log; (=16PYs
import org.apache.commons.logging.LogFactory; y8s!M
import org.flyware.util.page.Page; SR^_cpZoi
kF{*(r=.o
import com.adt.bo.Result; &(zfa&j|
import com.adt.service.UserService; E"%2)
import com.opensymphony.xwork.Action; aYn8^
hKNY+S})g
/** ~"lJ'&J}
* @author Joa T#
lP!c
*/ WKpA|
publicclass ListUser implementsAction{ !mRx$
%ul
q8Nn%o=5V
privatestaticfinal Log logger = LogFactory.getLog nx:KoB"ny
FP#FB$eP
(ListUser.class); .lBgp=!
1[E#vdbT
private UserService userService; 4Hb $0l
aup6?'G;
private Page page; dI*'!wK
Vvt ;
privateList users; <e)o1+[w
j J3zF3Id
/* #5&jt@NS
* (non-Javadoc) .fzu"XAPu
* cBYfXI0`
* @see com.opensymphony.xwork.Action#execute() Eq^uKi
*/ 3L_I[T$s
publicString execute()throwsException{ TwvAj#j
Result result = userService.listUser(page); a=xT(G0Re
page = result.getPage(); pilh@#_h
users = result.getContent(); w?mEuXc
return SUCCESS; K'1~^)*
} F_ 7H!F
8ga_pNe
/** xMs]Hs
* @return Returns the page.
/u`3VOn
*/ WlV
z,t'if
public Page getPage(){ F?u^"}%Fc
return page; E2AW7f(/
} Nt:8ogk/
kax\h
/** C;Ic
* @return Returns the users. aF8k/$u
*/ /}5B&TZ=(3
publicList getUsers(){ T7$S_
return users; k$Rnj`*^
} wU`!B<,j
Q0_>'sEM
/** !&]z*t
* @param page oc{EuW{Ag
* The page to set. [U\(G
*/ p"`%
publicvoid setPage(Page page){ u>.y:>
this.page = page; rrs"N3!aT
} 99OD=pxQ
7Bz*r0 9S
/** ~VTs:h
* @param users Y7U&Q:5'
* The users to set.
1;| LI?
*/ GZ}/leR
publicvoid setUsers(List users){
BRbV7&
this.users = users; ohc1 ~?3b
} Bmo$5$
VjbG(nB?_
/** W W "i
* @param userService ad n|N
* The userService to set. \&}G]
*/ jN/C'\QL
publicvoid setUserService(UserService userService){ Nm]%
}
this.userService = userService; (A/0@f1#
} S<6k0b(,_3
} S{p}ux[}=
.dq
"k
N<JHjq
rUwE?Ekn/
o*ANi;1]&B
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, 6ri#Lw
8
#oR/Nt
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 #Ogt(5Sd
$zkH|]
zZ
么只需要:
ErbSl
java代码: ,#'7)M D8
8*!|8 BPj^
m-1?\bs
<?xml version="1.0"?> _MYx%Z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;?IT)sNY
`Y3( ~~YGn
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }qC SS<a
K]N~~*`%`
1.0.dtd"> K%{ad1$c
s` >H
<xwork> Q!CO0w
Ly(P=M>"y
<package name="user" extends="webwork- @R:#"
RTd^ImV
interceptors"> ZL%VOxYqi
C?H{CP
<!-- The default interceptor stack name V,QwN&
WOndE=(V
--> RfbdBsL
<default-interceptor-ref 02 f9 w V
TGWdyIk
name="myDefaultWebStack"/> d$1#<