Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m^h"VH,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 US'X9=b_
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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 88h-.\%Z
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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 whoz^n3N E
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分页支持类: fu9y3`
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java代码: OnF+
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package com.javaeye.common.util; C;wN>HE
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import java.util.List; `?rPs8+R
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publicclass PaginationSupport { p{!aRB%
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publicfinalstaticint PAGESIZE = 30; ZP*Hx
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privateint pageSize = PAGESIZE; k\Oy\z@
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privateList items; I'BoP
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privateint totalCount; Tx0/3^\>8A
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privateint[] indexes = newint[0]; 1@E<5rp o
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privateint startIndex = 0; *f.eyg#
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public PaginationSupport(List items, int &pK1S>t
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totalCount){ ?;+=bKw0
setPageSize(PAGESIZE); sL~TV([6/
setTotalCount(totalCount); f`p`c*
setItems(items); FM0)/6I'x
setStartIndex(0); "f~S3 ?^!2
} TuBg 4\V
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public PaginationSupport(List items, int &B#HgWud
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totalCount, int startIndex){ l:8gCi
setPageSize(PAGESIZE); g{8>2OK$c
setTotalCount(totalCount); kxhvy,t
setItems(items); "X>Z!>
setStartIndex(startIndex);
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} %D\TLY
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public PaginationSupport(List items, int B y6:
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totalCount, int pageSize, int startIndex){ c 3 P
setPageSize(pageSize); -#Yg B5
setTotalCount(totalCount); 9O?.0L
setItems(items); /^DDU!=(<
setStartIndex(startIndex); {]]nQ
}
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publicList getItems(){ (#eB%
return items; so8isDC'9
} \UGs_5OT
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publicvoid setItems(List items){ * ?rw'
this.items = items; Xl2Fgg}#
} ToCB*GlL
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publicint getPageSize(){ t\CVL?e`
return pageSize; 5(%+8<2
} NV9D;g$Y
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publicvoid setPageSize(int pageSize){ 6t*pV
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this.pageSize = pageSize; -/B}XNW
} CP |N2rb
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publicint getTotalCount(){ 5sM-E>8G^{
return totalCount; ' ,a'r.HJH
} WsL*P.J
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publicvoid setTotalCount(int totalCount){ O=MO M
if(totalCount > 0){ be$wGO=Ts
this.totalCount = totalCount; E3_e~yu&
int count = totalCount / 6*S|$lo9B
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pageSize; e8a_)TU?
if(totalCount % pageSize > 0) uz&CUvos
count++; ;f^.7|
indexes = newint[count]; I/Hwf
for(int i = 0; i < count; i++){ O!hg@[\B+
indexes = pageSize * p` B48TW
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} k5$_Q#
}else{ J1 a/U@"
this.totalCount = 0; lHV
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} <o3e0JCq
} i t,i^32|
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publicint[] getIndexes(){ Z$k4T$,[-
return indexes; :tedtV~
} ^p|MkB?uM
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publicvoid setIndexes(int[] indexes){ @%O"P9;s
this.indexes = indexes; `]FA} wC
} Vu*yEF}
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publicint getStartIndex(){ `*&*jdq&i
return startIndex;
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} xA`Q4"[I
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publicvoid setStartIndex(int startIndex){ pez[qs
if(totalCount <= 0) 6U @3
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this.startIndex = 0; G+=euK2]
elseif(startIndex >= totalCount) go|/I&
this.startIndex = indexes &[3 xpi{v
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[indexes.length - 1]; I+!w9o2nZ
elseif(startIndex < 0) '8 1M%KO
this.startIndex = 0; ']ya_ v~e
else{ Zi|MWaA.f
this.startIndex = indexes Zuo7MR
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[startIndex / pageSize]; R^1sbmwk
} [0lCb"
} 'D1
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publicint getNextIndex(){ 2wlrei
int nextIndex = getStartIndex() + !Z
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- A
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pageSize; SJ6lI66OX
if(nextIndex >= totalCount) WLP A51R
return getStartIndex(); Qi&!IG
else X{| 1E85fl
return nextIndex; \wCj$-;Jt
} (8?t0}#t
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publicint getPreviousIndex(){ qmdl:J|?
int previousIndex = getStartIndex() - }9/30
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pageSize; z\pT nteO
if(previousIndex < 0) U? [a@Hj{
return0; lf4-Ci*X
else 05gU~6AF
return previousIndex; D(Pd?iQIO
} yc8iT`
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} c_~)#F%P
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抽象业务类 3Nd&*QSV
java代码: B[F x2r`0
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/** 4'Z=T\:
* Created on 2005-7-12 .2q7X{4=
*/ j5Vyo>
package com.javaeye.common.business; :7KcD\fCj
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import java.io.Serializable; ()6(eRGJ
import java.util.List; {CG%$rh
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import org.hibernate.Criteria; #Q.A)5_
import org.hibernate.HibernateException; "EQ`Q=8
import org.hibernate.Session; cgNK67"(
import org.hibernate.criterion.DetachedCriteria; x~j>Lvw L
import org.hibernate.criterion.Projections; s]#D;i8
import hk3}}jc
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org.springframework.orm.hibernate3.HibernateCallback; T6=, A }t-
import
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org.springframework.orm.hibernate3.support.HibernateDaoS -GLI$_lLF
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upport; {f((x1{HZx
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import com.javaeye.common.util.PaginationSupport; q(p]6Ha|
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public abstract class AbstractManager extends 'h53:?~
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HibernateDaoSupport { mHrt)0\_
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privateboolean cacheQueries = false; (2RZc].M~
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privateString queryCacheRegion; ]dHU
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publicvoid setCacheQueries(boolean FloCR=^H
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cacheQueries){ rz+)z:u
this.cacheQueries = cacheQueries; l
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} Eyv%"+>
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publicvoid setQueryCacheRegion(String Hphvsre<
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queryCacheRegion){ w[}5qAI5*f
this.queryCacheRegion = tGDsZ;3Yr
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queryCacheRegion; )ZC0/>R
} BF{v0Z0/}k
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publicvoid save(finalObject entity){ F`IV9qv
getHibernateTemplate().save(entity); |re)]%A?Fu
} 141@$mMzE
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publicvoid persist(finalObject entity){ F6J,:
getHibernateTemplate().save(entity); [vh&o-6
} {Z%4Pg
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publicvoid update(finalObject entity){ 2L Kpwz?
getHibernateTemplate().update(entity); L}NckL
} P>n}\"z4
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publicvoid delete(finalObject entity){ FC[8kq>Hk
getHibernateTemplate().delete(entity); `1k0wT(
} ,7-@eZ
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publicObject load(finalClass entity, $L%gQkz_
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finalSerializable id){ =kFZ2/P2t(
return getHibernateTemplate().load O(q1R#n-}+
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(entity, id); uv,&/,;S
} TK^9!3
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publicObject get(finalClass entity, !o +[L
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finalSerializable id){ +PT/pybA
return getHibernateTemplate().get J:WO%P=Q
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(entity, id); xh|NmZg
} }\Kki
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publicList findAll(finalClass entity){ H{qQ8j)
return getHibernateTemplate().find("from is`O,Met
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" + entity.getName()); R8ZI}C1
} rUgTJx&ds
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publicList findByNamedQuery(finalString "A?&`}%
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namedQuery){ vk;]9o j*
return getHibernateTemplate qcpAjjK
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().findByNamedQuery(namedQuery); JR>v
} c*R?eLt/
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publicList findByNamedQuery(finalString query, F&pJ faig
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finalObject parameter){ f-]5ZhM'
return getHibernateTemplate ~d5f]6#`
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().findByNamedQuery(query, parameter); oMdqg4HUF
} +2Xq+P
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publicList findByNamedQuery(finalString query, {jVEstP
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finalObject[] parameters){ ]CLt Km
return getHibernateTemplate ]&;M78^6
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().findByNamedQuery(query, parameters); AE?G+:B
} `]*BDSvE
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publicList find(finalString query){ {[W [S@+
return getHibernateTemplate().find q2>dPI;3T
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(query); LS(J%\hMDm
} 1UyQ``v/
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publicList find(finalString query, finalObject `-,yJ
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parameter){ f3bZ*G%f
return getHibernateTemplate().find iRwlK5(&
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(query, parameter); ^TWMYF-
} |~V`Es +j
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public PaginationSupport findPageByCriteria %+Az
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(final DetachedCriteria detachedCriteria){ 9bE/7v
return findPageByCriteria '5:P,1tWU
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =5zx]N1r
} ;R#:? r;t
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public PaginationSupport findPageByCriteria 9[L@*7A`m
N=?! ~n9Q-
(final DetachedCriteria detachedCriteria, finalint ^Ko{#qbl/
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startIndex){ BAUo`el5
return findPageByCriteria !uno!wUIYd
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(detachedCriteria, PaginationSupport.PAGESIZE, slV7,4S&!
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startIndex); `U~Y{f_!H
} tWo MUp
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public PaginationSupport findPageByCriteria -4}I02
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(final DetachedCriteria detachedCriteria, finalint ^mNPP:%iN
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pageSize, ":o1g5?
finalint startIndex){ fUJ\W"qya
return(PaginationSupport) pPezy:
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getHibernateTemplate().execute(new HibernateCallback(){ ;4g_~fB
publicObject doInHibernate /nX+*L}d/
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(Session session)throws HibernateException { TYs#v/)I
Criteria criteria = .x^`y2'U
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detachedCriteria.getExecutableCriteria(session); cv'Fc
int totalCount = VB+sl2V<h
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((Integer) criteria.setProjection(Projections.rowCount s\-^vj3
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()).uniqueResult()).intValue(); [xVE0l*\
criteria.setProjection JMT?+/Q bu
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(null); .W>8bg'u9
List items = 7%(|)3"V
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criteria.setFirstResult(startIndex).setMaxResults D(GAC!|/]
r7I,%}k
(pageSize).list(); j&S8x|5
PaginationSupport ps = kP6P/F|RcZ
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new PaginationSupport(items, totalCount, pageSize, >v+ia%o
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startIndex); Z~Mq5#3F
return ps; Q~'a1R
} z~g7O4#
}, true); ,8F?v~C
} ?Z<2zm%qV
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public List findAllByCriteria(final kRk=8^."By
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DetachedCriteria detachedCriteria){ t?-7Z6
return(List) getHibernateTemplate j=^b'dyL
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().execute(new HibernateCallback(){ }/Wd9x
publicObject doInHibernate g>[|/ z P
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(Session session)throws HibernateException { oadlyqlw#
Criteria criteria = =](c7HEQf
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detachedCriteria.getExecutableCriteria(session); qdn\8Pn
return criteria.list(); dwc$?Bg,5
} YLlw:jN
}, true); }G8RJxy
} 5T[9|zJs
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public int getCountByCriteria(final ':7%@2Zo
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DetachedCriteria detachedCriteria){ x*#F|N4~',
Integer count = (Integer) 1%L* 9>e
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getHibernateTemplate().execute(new HibernateCallback(){ MwxfTH"wi
publicObject doInHibernate z]k=sk
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(Session session)throws HibernateException { ;y#6Nx,:
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session);
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return b'$j* N
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criteria.setProjection(Projections.rowCount @1#$
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()).uniqueResult(); EX>|+zYL
} [Cz.K?+#M
}, true); ~Exd_c9
return count.intValue(); KJa?TwnC
} ?ng?>!
} 7"f$;CN?~
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用户在web层构造查询条件detachedCriteria,和可选的 laM0W5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u[U~`*i*rA
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PaginationSupport的实例ps。 G'(
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ps.getItems()得到已分页好的结果集 pBt/vS ad
ps.getIndexes()得到分页索引的数组 \n850PS
ps.getTotalCount()得到总结果数 @A6\v+ih
ps.getStartIndex()当前分页索引 (Jfi 3 m
ps.getNextIndex()下一页索引 v&(X&q
ps.getPreviousIndex()上一页索引 0D>~uNcT}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 hQBeM7$F_
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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 Be2@9
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一下代码重构了。 kq:,}fc;B
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我把原本我的做法也提供出来供大家讨论吧: i~z:Fe{
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首先,为了实现分页查询,我封装了一个Page类: >qx~m>2|8]
java代码: g\
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/*Created on 2005-4-14*/ 'N5qX>Ob
package org.flyware.util.page; 1X2oz
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.
/** Y[T;j p(k
* @author Joa _\"P<+!
* N{/q
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*/ X3]E8)645N
publicclass Page { )1j~(C)E8
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/** imply if the page has previous page */ e=Kv[R'(M
privateboolean hasPrePage; c6s(f
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/** imply if the page has next page */ `Dh %c%j)
privateboolean hasNextPage; N>Y`>5
Dt1{]~30
/** the number of every page */ #X"\:yN
privateint everyPage; [ZURs3q
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/** the total page number */ =Gd[Qn83.%
privateint totalPage; ]Nt97eD)
ACl:~7;
/** the number of current page */ \\hZlCV,
privateint currentPage; M)EKS
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/** the begin index of the records by the current uh#PZ
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query */ NfR, m]
privateint beginIndex; 8+gx?pb
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/** The default constructor */ =oT@h
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public Page(){ U]hQ#a+
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} kc8GnKM&mc
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/** construct the page by everyPage wc bs-arH
* @param everyPage /GM-#q
a
* */ Z
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public Page(int everyPage){
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this.everyPage = everyPage; W%Rh2l
} ~8pf.^,fi
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/** The whole constructor */ AV d
public Page(boolean hasPrePage, boolean hasNextPage, @dCu]0oNI
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tO[+O=d
int everyPage, int totalPage, -&,NM
int currentPage, int beginIndex){ x0lX6
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this.hasPrePage = hasPrePage; ~g|e?$j
this.hasNextPage = hasNextPage; ;S?1E:\av
this.everyPage = everyPage; K/\#FJno
this.totalPage = totalPage; ;xB"D0~,1
this.currentPage = currentPage; K:y q^T7
this.beginIndex = beginIndex; j&T/.]dX&
} N8D'<BUC
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/** qZ\zsOnp
* @return "mPa>`?
* Returns the beginIndex. _\]D<\St
*/ oN `tZ;a
publicint getBeginIndex(){ #mkr]K8A4
return beginIndex; m qw!C
} lmmyDg1R
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/** )&dhE^
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* @param beginIndex cWRB=`=qz
* The beginIndex to set. !+hX$_RT
*/ VpVw:Rh>
publicvoid setBeginIndex(int beginIndex){ huKz["]z[
this.beginIndex = beginIndex; p*npY"}v
} 6J|f^W-fs
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/** IB!Wrnj?
* @return 2WUBJ-qnuT
* Returns the currentPage. ^_+ks/
*/ GU[Cq=k
publicint getCurrentPage(){ `=KrV#/758
return currentPage; zi-+@9T
} TS[Z<m
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/** wd#AA#J;*
* @param currentPage yPQ{tS*t
* The currentPage to set. +'n1?^U
*/ /pk;E$qv
publicvoid setCurrentPage(int currentPage){ jQ^Ib]"K
this.currentPage = currentPage; bR8)s{p6
} SD.ze(P
OT *W]f
/** .ERO*Tj
* @return w`7l;7[
* Returns the everyPage. c=b\9!hr_E
*/ ^_=0.:QaW
publicint getEveryPage(){ GUp51*#XR
return everyPage; ;XtDz
} ]cA~%$c89s
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/** h{JVq72R
* @param everyPage % qE#^ U
* The everyPage to set. ?x[>g!r
*/ kW:!$MX!
publicvoid setEveryPage(int everyPage){ C,<TAm
this.everyPage = everyPage; _:K}DU'6
} jU#%@d6!#
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/** =f|>7m.p
* @return hy]AH)?pR
* Returns the hasNextPage. fZ376Z:S$
*/ KJ#c(yb9zR
publicboolean getHasNextPage(){ 8n:D#`K
return hasNextPage; 5Y&@
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} (qG$u&
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/** A+}4N%kh
* @param hasNextPage =|#-Rm^YB
* The hasNextPage to set. PA=BNKlH
*/ *7v PU:Q[
publicvoid setHasNextPage(boolean hasNextPage){ WcJ{}V9
this.hasNextPage = hasNextPage; tV,zz;* Oe
} y@Or2bO#
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/** .F6#s
* @return Y~:7l5C
* Returns the hasPrePage. kL3=7t^ 1
*/ &
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publicboolean getHasPrePage(){ a,E;R$[!
return hasPrePage; jCl[!L5/1
} LgnGqIlx
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/** l
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* @param hasPrePage \mDm*UuG
* The hasPrePage to set. PaZYs~EO
*/ gJ7$G3&oZg
publicvoid setHasPrePage(boolean hasPrePage){ |S8pq4eKJ_
this.hasPrePage = hasPrePage; d{m0 uX56
} Fi`:G}
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/** zKutx6=aj
* @return Returns the totalPage. hf-S6PEsM
* ,]Ma, 2
*/ dkLR
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publicint getTotalPage(){ *,pqpD>
return totalPage; h`Mf;'P
} p(8\w-6
CP'-CQ\Q
/** 7.t$#fzi
* @param totalPage wf4Q}l2,d
* The totalPage to set. F)IP~BE-k
*/ =3:ltI.'*I
publicvoid setTotalPage(int totalPage){ A^7!+1*K+
this.totalPage = totalPage; 6{~I7!m"
} AK!G#ug
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} O`=Uq0Vv
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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 \2`U$3Q
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个PageUtil,负责对Page对象进行构造: lrzW H0Q
java代码: 3{l"E(qqZ
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/*Created on 2005-4-14*/ Ame%:K!t
package org.flyware.util.page; ^:j$p,0e*S
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import org.apache.commons.logging.Log; .<B1i
import org.apache.commons.logging.LogFactory; hTm}j,H
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/** rUO{-R
* @author Joa 8f.La
* ?1uAY.~ZZB
*/ 8{YxUD
publicclass PageUtil { V("1\
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privatestaticfinal Log logger = LogFactory.getLog #L)rz u
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(PageUtil.class); 'w2;oO
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/** DbN'b(+
* Use the origin page to create a new page (AYD@
* @param page 4=Ey\Px
* @param totalRecords 1|VJN D
* @return NP8TF*5V
*/ 7yp*I[1Qf>
publicstatic Page createPage(Page page, int $#r(1 Ev
)YFs
totalRecords){ 1%,Z&@^j
return createPage(page.getEveryPage(), l_c?q"X
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page.getCurrentPage(), totalRecords); 5o/rV.I
} Jy_'(hG
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/** P]B#i1
* the basic page utils not including exception Os{qpR^<I:
hgK=fHJk
handler >gl.(b25C
* @param everyPage P `"7m-
* @param currentPage kR|y0V {K*
* @param totalRecords eW0=m:6
* @return page eXK`%'
*/ 9K|lU:,
publicstatic Page createPage(int everyPage, int }U9jsm
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currentPage, int totalRecords){ j,XKu5w)Oi
everyPage = getEveryPage(everyPage); {rZ"cUm
currentPage = getCurrentPage(currentPage); arZIe+KW
int beginIndex = getBeginIndex(everyPage, <Xx\F56zp
I8?[@kg5b'
currentPage); @nu/0+8h{
int totalPage = getTotalPage(everyPage, TXcKuo=
l'QR2r7&.
totalRecords); zwtsw [.
boolean hasNextPage = hasNextPage(currentPage, ]B4mm__
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totalPage); OX4D'
boolean hasPrePage = hasPrePage(currentPage); )*ckJK
=]e^8;e9
returnnew Page(hasPrePage, hasNextPage, fXe-U='
everyPage, totalPage, 4Z}{hc\J
currentPage, s? k[_|)!
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beginIndex); &J$5+"/;X
} 9#ft;c
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privatestaticint getEveryPage(int everyPage){ $sZHApJV+
return everyPage == 0 ? 10 : everyPage; *a!!(cZZ
} dn_OfK
8n5nHne
privatestaticint getCurrentPage(int currentPage){ aUK4{F ;
return currentPage == 0 ? 1 : currentPage; Nl`ry2"<
} C4]%pi
2<Bv=B
privatestaticint getBeginIndex(int everyPage, int @88i/ Z_
Ky#B'Bh}`g
currentPage){ t[hocl/6
return(currentPage - 1) * everyPage; on?/tHys
} +E|ouFI
9^ p{/Io
privatestaticint getTotalPage(int everyPage, int gqRTv_ ;
% Au$E&sj
totalRecords){ aa8Qslm
int totalPage = 0; bK\WdG\;
b6&NzUt34V
if(totalRecords % everyPage == 0) !"%sp6Wc
totalPage = totalRecords / everyPage; mthl?,I|
else o'/C$E4W
totalPage = totalRecords / everyPage + 1 ; ;bZ*6-\!-
1Uk~m
return totalPage; JyC&L6[]Z
} )C]&ui~1
*Ne&SXg
privatestaticboolean hasPrePage(int currentPage){ c8tC3CrKp=
return currentPage == 1 ? false : true; h;qy5KS
} ^alZ\!B8
R2THL
privatestaticboolean hasNextPage(int currentPage, f\|?_k]
{@__%=`CCS
int totalPage){ K#hY bDm
return currentPage == totalPage || totalPage == qO{ ZZ*
Lo5@zNt%W
0 ? false : true; y[6&46r7D
} jUvA<r
L~y t AZ,
Qk.Q9@3W
} puN=OX}C
M5WtGIV
/1~|jmi(
'QojSq
,G|aLBn
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 5;8B!%b
\K~fRUo]=c
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ;c
Co+(
aroVyUs3j
做法如下: "%''k~UD4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 &4&33D
.#55u+d,
的信息,和一个结果集List: 4z%#ZIy3
java代码: |( 9#vt#
)S}; k=kG
jS3(>
/*Created on 2005-6-13*/ F] ?@X
package com.adt.bo; 4UD=Y?zK
kEhm'
import java.util.List; ct4 [b|
i4zV(
import org.flyware.util.page.Page; Qy5Os?9"
D?yE$_3>c
/** H9VXsFTW
* @author Joa _b_?9b-)D
*/ ``|RO[+2
publicclass Result { dMs||&|&
{{*]bGko
private Page page; AXP`,H
E<Dh_K
private List content; 6QLQ1k`
BCUt`;q ]B
/** BBR"HMa4
* The default constructor &49$hF
g6"
*/ Mp"'?zf
public Result(){ =Y/fF
super(); pq[X)]z|
} W.`Xm(y
Zfy~mv$
/** zf3:<CRX5
* The constructor using fields Va@6=U7c
* T3 9C lH
* @param page VP%i1|XZJ
* @param content 1%spzkE 3P
*/ /MqXwUbO
public Result(Page page, List content){ uR:=V9O
this.page = page; $HBT%g@UN
this.content = content; juMxl
} tpa^k
(#bp`Kih
/** xd|~+4
* @return Returns the content. !ASoXQRz
*/ g+ }s:9
publicList getContent(){ K6v
$#{$6
return content; aM{@1mBm
} 8pk#sJ51
f(6UL31
/** 8wX+ZL:9
* @return Returns the page. Z.:<TrN
*/ Q^lQi\[
public Page getPage(){ kOAY@a
return page; UXwB$@8
} B)rr7B
PW*;S p
/** VX;zZ`BJ
* @param content )
\-96 xd
* The content to set. cophAP
*/ g=xv+e
public void setContent(List content){ au~]
this.content = content; -VWCD,c
} qE0FgqRB
<mZrR3v'D
/** Dd0Qp-:2
* @param page \5Vp6^
* The page to set. %6A-OF
*/ [A"H/Qztk
publicvoid setPage(Page page){ 'h^-t^:<>b
this.page = page; ik2-
OM
} &[5n0e[
} `RL,ZoYuu
8
"_Bq
@ /UOSU
h4aygc
`6Ureui2?
2. 编写业务逻辑接口,并实现它(UserManager, )W8L91-
@7@e`b?
UserManagerImpl) W$" Y%^L
java代码: h
L]8e>a?
z;dcAdz9
k,,!P""
/*Created on 2005-7-15*/ 731h
~x!u
package com.adt.service; (0E U3w?]
Vk-W8[W 7
import net.sf.hibernate.HibernateException; ~reQV6oQua
.3{[_iTM
import org.flyware.util.page.Page; 2{t)DUs
{)B9Z
I{+A
import com.adt.bo.Result; CKv&Re
F!7f_m0=
/** g7xbyBo7
* @author Joa +/y{^}b/
*/ xLx"*jyL
publicinterface UserManager { K2cq97k,d
8jy-z"jc
public Result listUser(Page page)throws m|]j'g?{}(
rDVgk6
HibernateException; }RcK_w@Jx)
Hp\Ddx >Jd
} V@vhj R4r\
eo1&.FQu
XzT78
b fp,zs
\ Y*h
java代码: },DyU
bh6d./
>0PUWr$8
/*Created on 2005-7-15*/ f.||PH
package com.adt.service.impl; hPan
+0]'| t F>
import java.util.List; g<fDY6jt
[ njx7d
import net.sf.hibernate.HibernateException; XtCoX\da
bvl~[p$W3
import org.flyware.util.page.Page; $^}[g9]1
import org.flyware.util.page.PageUtil;
jip\4{'N
f
hQy36i@
import com.adt.bo.Result; 'pan9PW
import com.adt.dao.UserDAO; 79D=d'eA
import com.adt.exception.ObjectNotFoundException; 3 brb*gI_b
import com.adt.service.UserManager; !w q4EV
ZA0i)(j*Mn
/** 5 U%MoH
* @author Joa ql^g~b
*/ /xcJo g~F,
publicclass UserManagerImpl implements UserManager { QhsMd-v
tXt:HVN
private UserDAO userDAO; 7))\'\
%X;7--S%?g
/** "2a$1Wmj(
* @param userDAO The userDAO to set. 0Cl,8P
*/ <B!'3C(P
publicvoid setUserDAO(UserDAO userDAO){ ##H;Yb
this.userDAO = userDAO; Y}ng_c
} e
RA7i
2\VAmPG.Zs
/* (non-Javadoc) Yx5J$!Ld
* @see com.adt.service.UserManager#listUser 4E2yH6l
ejVdxVr \7
(org.flyware.util.page.Page) 5MxH)~VQoM
*/ CWs: l3_yn
public Result listUser(Page page)throws || [89G
}'%^jt[3
HibernateException, ObjectNotFoundException { Va7c#P?
int totalRecords = userDAO.getUserCount(); ~L bS~_\C=
if(totalRecords == 0) O#Z/+\U
throw new ObjectNotFoundException -I ?z-?<D
9 ~~qAoD
("userNotExist"); ^]6M["d/p
page = PageUtil.createPage(page, totalRecords); ABc)2"i:*
List users = userDAO.getUserByPage(page); RlrZxmPV>O
returnnew Result(page, users); id^|\hDR
} 6
}! Z"
pTWg
m\h
} , 9mgYp2
e8,{|a
}!8nO;
Gzw@w{JBL
!6H uFf
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :[xvlW29
F.<L>
G7{1
询,接下来编写UserDAO的代码: cGNvEM(4AV
3. UserDAO 和 UserDAOImpl: Q"%S~'
java代码: qe$33f*
j$Nf%V 6Y
(S|a 9#
/*Created on 2005-7-15*/ (YwalfG {C
package com.adt.dao; +3;Ody"59
g:_hj_1Y M
import java.util.List; ;1 |x
~^&R#4J
import org.flyware.util.page.Page; II;Te7~
~.Cv
DJy
import net.sf.hibernate.HibernateException; @RGDhwS47
CbOCk:,g5
/** Stxp3\jEn
* @author Joa q\Rq!7(
*/ SWs3SYJ\
publicinterface UserDAO extends BaseDAO { T~Ly^|Ihz
fG&=Ogy
publicList getUserByName(String name)throws jY/ARBC}H
gO='A(Y
HibernateException; WULAty
=A@>I0(7
publicint getUserCount()throws HibernateException; qZ*f%L(
+~Tu0?{Z 0
publicList getUserByPage(Page page)throws ZIpD{ >/
q8>t!rh<R
HibernateException; R4{-Qv#8
q
E1 |<Pt
} "_< 9PM1t
8[zb{PRu
>;4!O%F
vvq/
p|3b/plZ
java代码: NvJV</l6A
:+ Jt^
6
ET:T7
/*Created on 2005-7-15*/ 1u~ MXGF
package com.adt.dao.impl; "3fBY\>a
5Fbs
WW2
import java.util.List; 2q PhLCeZ
:et#0!
import org.flyware.util.page.Page; =dzWmL<~8
$DebXxJw0l
import net.sf.hibernate.HibernateException; 4w4^yQE
import net.sf.hibernate.Query; +
P7o4]:/
?Ik4
import com.adt.dao.UserDAO; ~y
/!fnv
aD9q^EoEs
/** Wd8Ru/
* @author Joa *geN[[
*/
>&U@f
public class UserDAOImpl extends BaseDAOHibernateImpl ST
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m#e*c[*G
implements UserDAO { V`#.7uUP
C\}/"
/* (non-Javadoc) lpgd#vr
* @see com.adt.dao.UserDAO#getUserByName y('k`>C
RWKH%C[Yd
(java.lang.String) FhkkWWL
*/ 3mO;JXd
publicList getUserByName(String name)throws m$wlflt
]~0}=,H$N
HibernateException { 8'#/LA[uPe
String querySentence = "FROM user in class jlqv2V7=/
/,s[#J
com.adt.po.User WHERE user.name=:name"; }Fa%%}
Query query = getSession().createQuery J?&l*_m;t
V'G Ju
(querySentence); MS3=~*+
query.setParameter("name", name); "OmD@
EMT
return query.list(); ?o*I9[Z)
} uO6{r v\
YKZa$@fA?
/* (non-Javadoc) @1-F^G%p8
* @see com.adt.dao.UserDAO#getUserCount() z6*<V5<7
*/ 3jZ6kfj
publicint getUserCount()throws HibernateException { $}GTG'*.
int count = 0; xQ4%e[/
String querySentence = "SELECT count(*) FROM u92^(|
y<:<$22O
user in class com.adt.po.User"; ^D{lPu
3
Query query = getSession().createQuery ^oM|<";!?D
*\G)z|^yx
(querySentence); 0bS|fMgc
count = ((Integer)query.iterate().next :A1:
_;
Y`
()).intValue(); Iu[|<Cx
return count; lpB3&H8&
} %NHkDa!
2]cRXJ7h
/* (non-Javadoc) NSQp<
m
* @see com.adt.dao.UserDAO#getUserByPage p-GAe,2q
T;5r{{
(org.flyware.util.page.Page) #,d I$gY
*/ c; 2#,m^
publicList getUserByPage(Page page)throws YW/QC'_iC
he(A3{'
HibernateException { `=lc<T^
String querySentence = "FROM user in class "N?+VkZEv
9$qm>,o
com.adt.po.User"; ?9{~> 4@
Query query = getSession().createQuery QXgE
dsw
)wvHGecp*
(querySentence); Ho;X4lo[j
query.setFirstResult(page.getBeginIndex()) yQ,{p@#X8
.setMaxResults(page.getEveryPage()); V[o`\|<
return query.list(); c0&Rg#
} -G7TEq)
2-N 'ya
} 4JGtI*%5lq
/U&Opo
{aO
9h4({EE2t
aJ") <_+
~*A8+@\R
至此,一个完整的分页程序完成。前台的只需要调用 4)|8Eu[p7
phnV7D(E
userManager.listUser(page)即可得到一个Page对象和结果集对象 VHJM*&5
-h|B1*mt
的综合体,而传入的参数page对象则可以由前台传入,如果用 !8NC# s
G 0%6ch^%
webwork,甚至可以直接在配置文件中指定。 %w7u]-tR
C?Bl{4-P}*
下面给出一个webwork调用示例: i.D3'l
java代码: aI^/X{d
}G4ztiuG
*t[. =_v
/*Created on 2005-6-17*/ E:9"cxx
package com.adt.action.user; #S&Tkip]"W
/DQaGq/Ld
import java.util.List; 2'EUy@0
jB{4\)
import org.apache.commons.logging.Log; hd),&qoW?
import org.apache.commons.logging.LogFactory; u!"t!2I
import org.flyware.util.page.Page; _8Kx6s%
NS%WeAf
import com.adt.bo.Result; 3RLFp\i"s
import com.adt.service.UserService; %LVm3e9
import com.opensymphony.xwork.Action; ho##Z*O
= C4
/** EkgE_8
* @author Joa &e6CJ
*/ &wD;SMr<
publicclass ListUser implementsAction{ 35E _W>n
:8CvRO*<
privatestaticfinal Log logger = LogFactory.getLog 1$M@]7e+!+
[<DZ*|+
(ListUser.class); KD`IX-r{s
AC>`'Gx
private UserService userService; QFYWA1<pDh
Tb3J9q+ya
private Page page; O+y-}7YX
Vn*tpbz
privateList users; Zt.'K(]2h
/"eey(X
/* Jn{OWw2
* (non-Javadoc) sCR67/
* B!vmQR*1
* @see com.opensymphony.xwork.Action#execute() IiY/(N+J
*/ dZi"$ g
publicString execute()throwsException{ 0TQ$C-%
Result result = userService.listUser(page); +=O5YR!{
page = result.getPage(); S H!
users = result.getContent(); 6Yx4lWBR?
return SUCCESS; .Fdgb4>BXX
} :2
*g~6
0q&<bV:D
/** $0vb^
* @return Returns the page. 6
J{k(H$3
*/ zT!drq: x
public Page getPage(){ W[Ls|<Q
return page; {phNds%
} &*+'>UEe5
"rx-_uK*
/** O^oWG&Y;v
* @return Returns the users. :Zlwp6
*/ BO;6
u^[
publicList getUsers(){ ;7}VBkH
return users; Wf|Q$MHos
} gIjh:_ Pz
7 @D@ucL
/** #"@|f
* @param page \WxukYH
* The page to set. vEJWFoeEFm
*/ 0cj>mj1M
publicvoid setPage(Page page){ e
9;~P}
this.page = page; #ZB~x6i6
} Yt;MV)
#qK:J;Sn3
/** |y(Q
* @param users f&Gt|
* The users to set. KV(Q;~8"X
*/ >CHrg]9
publicvoid setUsers(List users){ <J)]mh dm
this.users = users; E7rDa1
} YNQY4\(
<0Xf9a8>
/** \W~N
* @param userService E|iQc8gr&
* The userService to set. F(>Np2oi6
*/ .+$Q<L
publicvoid setUserService(UserService userService){ <3LbNFP
this.userService = userService; 3 2&;`]C
} M/b Sud?@%
} a<^ v(r
I>W=x'PkLn
6 (]Dh;gC
_852H$H\
EV]1ml k$
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, hgPa6Kd
;ub;lh 3
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 V<GHpFi0
X
$jWo@
么只需要: ZOh`(})hy
java代码: X%
t1T4
UtoT
os=e|vkB*
<?xml version="1.0"?> u_oaebOrpP
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork k\5c|Wq|g
~%<X0s|
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9jM}~XvV
H\ F:95
1.0.dtd"> Lt64JH^lz
<:+ x+4ru
<xwork> | )K8N<n
V%rzk*LA
<package name="user" extends="webwork- @>,^":`#
]cHgleHQ
interceptors"> +r2+X:#~T
]d$8f
<!-- The default interceptor stack name ^aItoJq
0"<H;7K#W
--> V?6a8lJ
<default-interceptor-ref ZMQZs~;~d
.*OdqLz
name="myDefaultWebStack"/> wr$("A(
oH97=>
<action name="listUser" y%"{I7!A
DX#Nf""Pw
class="com.adt.action.user.ListUser"> <cps2*'
<param dqU~`b9
"g5^_UP
name="page.everyPage">10</param> <? q?Mn
<result } Y12
n(1l}TJy
name="success">/user/user_list.jsp</result> -*1d!
</action> f,U.7E
UXJeAE-
</package> &*M!lxDN
"q3ZWNS'w
</xwork> K@
I9^b
(S>C#A=E\
,0M_Bk"
V(H1q`ao9
o_izl\
03$mYS_?
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 R`NYEptJ
KLST\Ln:
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。 B6MB48#0gs
T6\[iJI|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 cN/6SGHK
W=~~5jFX
;AG8C#_
.]8ZwAs=&
d[iQ`YW5
我写的一个用于分页的类,用了泛型了,hoho bV^rsJm
x]}^v#
java代码: S|Q@:r"
P_F30x(
lU8l}Ndz"
package com.intokr.util; (p" %O
4>wP7`/+y
import java.util.List; OIGY`
Zu*F#s!tUI
/** \1k79 c
* 用于分页的类<br> Hus)c3Ty7
* 可以用于传递查询的结果也可以用于传送查询的参数<br> '{cIAw/"n
* E^B'4
* @version 0.01 L^1NY3=$
* @author cheng R)c?`:iUB
*/ A#e%^{q$
public class Paginator<E> { Tf>bX_L?
privateint count = 0; // 总记录数 ;YaQB#GK%
privateint p = 1; // 页编号 6fkRrD
privateint num = 20; // 每页的记录数 0CHH)Bku
privateList<E> results = null; // 结果 5?f ^Rz
"BM#4
/** 0Um2DjTCG
* 结果总数 d-oMQGOklb
*/ !Jo_"#5
publicint getCount(){ VF+KR*
return count; Sj3+l7S?
} xVw9v6@`h
2R[:]-b
publicvoid setCount(int count){ sU=H&D99
this.count = count; D(~U6SR
} %Tfbsyf%f
]=\].% >
/** H%[eV8
* 本结果所在的页码,从1开始 P9R9(quI
* '6DBs8>1
* @return Returns the pageNo.
{y)=eX9
*/ =7?4eYHC
publicint getP(){ u^&^UxCA
return p; 4VHn \
} ><4<yj1
jVEGj5F;N
/** 0Fq}
N
* if(p<=0) p=1 qv-8)MSr
* m&d|t>3<
* @param p `~cqAs}6]Q
*/ ___~D
dq
publicvoid setP(int p){ R8K&R\
if(p <= 0) %:i7s-0w
p = 1; _?nL+\'V
this.p = p; ${DUCud,kY
} % 7hrk
Kf3"Wf^q
/** t^&Cxh
* 每页记录数量 [:dY0r+
*/ pd?Mf=>#
publicint getNum(){ <3nMx^
return num; wH*-(*N"
} 7 W5@TWM
jVi) Efy
/** [z:!j$K
* if(num<1) num=1 &0d#Y]D4`
*/ b1cy$I
publicvoid setNum(int num){ #`^}PuQ
if(num < 1) )+#` CIv
num = 1; H8=N@l
this.num = num; /l3V3B7
} 7^avpf)>
Y/F6\oh
/** -E[Kml~U
* 获得总页数 9+|$$)
*/ KM,\
publicint getPageNum(){ +w`2kv
return(count - 1) / num + 1; w?L6!) oiz
} & l<.X
YP oSRA L
/** [NTzcSN.
* 获得本页的开始编号,为 (p-1)*num+1 :
6jbt:
*/ .xCZ1|+gG
publicint getStart(){ H_7/%noS5
return(p - 1) * num + 1; $ Gf(38[w
} KYm0@O>;
&C_j\7Dq
/** cVv=*81\
* @return Returns the results. `bq<$e
*/ w7L{_aom
publicList<E> getResults(){ \
#F
return results; +Ze}B*0
} hPkp;a #
=IZT(8
public void setResults(List<E> results){ '@v\{ l
this.results = results; @?sRj&w
} AYBns]!
#^0R&) T
public String toString(){ &u."A3(
StringBuilder buff = new StringBuilder CO/]wS
T=DbBy0-
(); ^dWa;m]l
buff.append("{"); i}f"yO+Q+
buff.append("count:").append(count); iQ67l\{R
buff.append(",p:").append(p); 6q\bB
buff.append(",nump:").append(num); w{8xpAqm
buff.append(",results:").append j^sg6.Z*
xK[ou'
(results); Oi.C(@^(
buff.append("}"); c^xIm'eob
return buff.toString(); LVM%"sd?
} n`_{9R
,&A7iO
} RMV/&85?y
Qp5VP@t
;+R&}[9,A)