Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 J| 'T2g
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s#d# *pgzh
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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 x(t}H8q
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改
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分页支持类: hVGakp9WE
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java代码: CLYcg$V
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package com.javaeye.common.util; &[Sw:{&*jv
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import java.util.List; )E4COw+
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publicclass PaginationSupport { Wc]Fg9E
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publicfinalstaticint PAGESIZE = 30; ,U7hzBj8k
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privateint pageSize = PAGESIZE; |RjjP 7
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privateList items; /S;?M\
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privateint totalCount; >yWJk9hf
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privateint[] indexes = newint[0]; "^trHh8=
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privateint startIndex = 0; d@w
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public PaginationSupport(List items, int de`6%%|
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totalCount){ Awr]@%I
setPageSize(PAGESIZE); }>OE"#si
setTotalCount(totalCount); Hv`Zc*
setItems(items); '8Gw{&&
setStartIndex(0); snK9']WXo
} H~$|y9>qI
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public PaginationSupport(List items, int }YSH8d
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totalCount, int startIndex){ -[7.VP
setPageSize(PAGESIZE); nut7b
setTotalCount(totalCount); ,2cw9?<
setItems(items); +Rh'VZJs
setStartIndex(startIndex); ZU@V]+ww
} !PQRlgcG
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public PaginationSupport(List items, int ~j4=PT
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totalCount, int pageSize, int startIndex){ K{iayg!k
setPageSize(pageSize); *1%g=vb
setTotalCount(totalCount); sV+>(c-$
setItems(items); x[?_F
setStartIndex(startIndex); wXZ-%,R-D
} ::5-UxGL<2
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publicList getItems(){ EP8LJzd"
return items; mb/3
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} O^<6`ku
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publicvoid setItems(List items){ y~d W=zO
this.items = items; r'!l`
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} Hc+<(g
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publicint getPageSize(){ _AO0:&
return pageSize; 'v,W
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} =DCQ!02
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publicvoid setPageSize(int pageSize){ 4 '+)9&g
this.pageSize = pageSize; @2u<Bh}}
} J)-owu;
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publicint getTotalCount(){ 3LTO+>, |"
return totalCount; '|cuVxcE55
} 8%NX)hZyq}
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publicvoid setTotalCount(int totalCount){ "2h#inS
if(totalCount > 0){ lfKknp#B/O
this.totalCount = totalCount; L"Gi~:z
int count = totalCount / P o_9M4kU
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pageSize; 2Fh_
if(totalCount % pageSize > 0) FFkG,XH
count++; jmb\eOq+~V
indexes = newint[count]; Kzm_AHA)
for(int i = 0; i < count; i++){ 3}+/\:q*
indexes = pageSize * &l.^UQ
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} 7q?YdAUz
}else{ <
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this.totalCount = 0; ^U =`Rx
} !Q#b4 f
} <hea%6
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publicint[] getIndexes(){ Q?>#sN,
return indexes; 01dx}L@hz
} EvYw$j
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publicvoid setIndexes(int[] indexes){ =UV?Pi*M>
this.indexes = indexes; Y[H_?f=;%
} )FP|}DCxQ
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publicint getStartIndex(){ m^=,
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return startIndex; V":BAn
} S ~_%
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publicvoid setStartIndex(int startIndex){ GBQb({
if(totalCount <= 0) BOWTH{KR<<
this.startIndex = 0; r:q#l~;^
elseif(startIndex >= totalCount) :b>|U"ux
this.startIndex = indexes q5A+%#
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[indexes.length - 1]; B -KOf
elseif(startIndex < 0) -{wuF0f
this.startIndex = 0; T/K.'92S
else{ ~L1O\V
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this.startIndex = indexes Z^|C~lp;n
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[startIndex / pageSize]; `8-aHPF-
} !G,$:t1-=V
} @v'D9 ?
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publicint getNextIndex(){ gv,T<A?Z2
int nextIndex = getStartIndex() + :}-u`K*
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pageSize; EzyIsp> _
if(nextIndex >= totalCount) <d^7B9O?&w
return getStartIndex(); |x4yPYBL
else [vi4,'wm
return nextIndex; w(U/(C7R
} Q. XsY.{
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publicint getPreviousIndex(){ K4yYNlY
int previousIndex = getStartIndex() - =gn}_sKNE
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pageSize; IX(yajc[~M
if(previousIndex < 0) =,
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return0; aC},h
else S3'g(+S
return previousIndex; 3azc `[hl
} z]YhQIU4n8
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} AN>`M?EQ
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抽象业务类 L8zqLDi&
java代码: qWpC e*C
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/** J9FNjM[qe
* Created on 2005-7-12 t/ 1NTa
*/ _pGviGR
package com.javaeye.common.business; O}-7 V5
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import java.io.Serializable; Mh|`XO.5I
import java.util.List; Sg$\ab $
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import org.hibernate.Criteria; &-:yn&f7
import org.hibernate.HibernateException; 48Lmy<}*
import org.hibernate.Session; (3h*sd5ly
import org.hibernate.criterion.DetachedCriteria; b1u'ukDP\
import org.hibernate.criterion.Projections; % 4"~O
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import DG\YZV4
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org.springframework.orm.hibernate3.HibernateCallback; N]}+F w\5
import j*u9+.
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org.springframework.orm.hibernate3.support.HibernateDaoS 'lk74qU$
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upport; N^]>R:Stu
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import com.javaeye.common.util.PaginationSupport; \#jDQ
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public abstract class AbstractManager extends ,rI
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HibernateDaoSupport { } XU:DE
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privateboolean cacheQueries = false; kA;Tr4EA6
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privateString queryCacheRegion; <M?#3&5A
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publicvoid setCacheQueries(boolean GKhwn&qCKb
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cacheQueries){ -!>ZATL<B
this.cacheQueries = cacheQueries; bMZn7c
} +fQL~0tA
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publicvoid setQueryCacheRegion(String eKz~viM'
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queryCacheRegion){ _0q~s@-
this.queryCacheRegion = TQd FC\@f"
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queryCacheRegion; [0ffOTy
} ]C6[`WF
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publicvoid save(finalObject entity){ h;p%EZ
getHibernateTemplate().save(entity); i;zGw.;Q
} F` 5/9?;|
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publicvoid persist(finalObject entity){ !TL}~D:J
getHibernateTemplate().save(entity); /_OZ1jX
} ]MLLr'6?
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publicvoid update(finalObject entity){ {dx /p-Tv
getHibernateTemplate().update(entity); ;u};&sm
} <o7#?AcPu
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publicvoid delete(finalObject entity){ B=bI'S8\
getHibernateTemplate().delete(entity); F2`htM@,
} '#i]SU&*
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publicObject load(finalClass entity, 0 ;_wAk
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finalSerializable id){ B H0#Q5
return getHibernateTemplate().load LL[#b2CKa
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(entity, id); C$td{tM
} #!Cter2
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publicObject get(finalClass entity, V"by9p|V`
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finalSerializable id){ z2Y_L8u2
return getHibernateTemplate().get W+f&%En
h @,e`Z
(entity, id); IO!1|JMr6
} (d'j'U:C
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publicList findAll(finalClass entity){ e9`uD|KAS|
return getHibernateTemplate().find("from wvmg)4,
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" + entity.getName()); b;J0'o^G|
} .)@tXH=}+
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publicList findByNamedQuery(finalString 2WPF{y%/
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namedQuery){ ]fADaw-R
return getHibernateTemplate .5!sOOs$P
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().findByNamedQuery(namedQuery); -RH4y 2
} KM5DYy2 A6
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publicList findByNamedQuery(finalString query, /iTUex7T
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finalObject parameter){ YNg\"XjJM<
return getHibernateTemplate |)?aH2IL
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().findByNamedQuery(query, parameter); 1t[;` iZ
} fATA%eA8;
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publicList findByNamedQuery(finalString query, &V#z kW
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finalObject[] parameters){ gR;8ht(pd(
return getHibernateTemplate uspkn1-
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().findByNamedQuery(query, parameters); Sj0 ucnuHi
} <E[HlL
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publicList find(finalString query){ ;5D@kS^
return getHibernateTemplate().find q:
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(query); Tr+h$M1_Ja
} $m:2&lU3
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publicList find(finalString query, finalObject [ZKtbPHb
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parameter){ {UdcX~\~
return getHibernateTemplate().find AB2mt:^
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(query, parameter); (:?5 i`
} pHj[O?F
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public PaginationSupport findPageByCriteria '&-5CpDUs
< QDr,Hj
(final DetachedCriteria detachedCriteria){ =mKfFeO.
return findPageByCriteria hJw
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); j<ABO")v
} qe5tcv}u
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public PaginationSupport findPageByCriteria !F+|Y"c
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(final DetachedCriteria detachedCriteria, finalint ZDOF
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startIndex){ S,*{q(
return findPageByCriteria 5\akI\
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(detachedCriteria, PaginationSupport.PAGESIZE, }osHA`x"2
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startIndex); j-lSFTo
} &'5@azU
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public PaginationSupport findPageByCriteria "x#]i aDjf
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(final DetachedCriteria detachedCriteria, finalint UAsF0&]
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pageSize, a>o"^%x
finalint startIndex){ KTG:I@|C
return(PaginationSupport) k4qLB1&,
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getHibernateTemplate().execute(new HibernateCallback(){ !,cQ'*<W8-
publicObject doInHibernate /d0Q>v.g
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(Session session)throws HibernateException { 6=ZRn gQ
Criteria criteria = Q`.'-iq
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detachedCriteria.getExecutableCriteria(session); Ur'9bl{5
int totalCount = LP^p~5Az
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((Integer) criteria.setProjection(Projections.rowCount 9W{,=.%MX$
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()).uniqueResult()).intValue(); 6gj]y^}
criteria.setProjection |av*!i5Q
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(null); BFBR/d[&
List items = j 0g5<M
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criteria.setFirstResult(startIndex).setMaxResults PD6MyW05%9
; cGv] A+
(pageSize).list(); U9 1 &|
PaginationSupport ps = Uc_jQ4e_
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new PaginationSupport(items, totalCount, pageSize, i&'#+f4t
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startIndex); @GN(]t&3
return ps; 9{_8cpm4
} b;S6'7Jf9
}, true); }1QI"M*
} J.1O/Pw!.a
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public List findAllByCriteria(final F(#ha J$>
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DetachedCriteria detachedCriteria){ r?fH
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return(List) getHibernateTemplate xDR9_
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().execute(new HibernateCallback(){ JZ `>|<W
publicObject doInHibernate r
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(Session session)throws HibernateException { Z}|TW~J=
Criteria criteria = ?q\FLb%"7
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detachedCriteria.getExecutableCriteria(session); 3\;v5D:
return criteria.list(); YTQ5sFuGM
} a
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}, true); %1Yz'AiW[
} j7K5SS_]
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public int getCountByCriteria(final ^;.T}c%N
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DetachedCriteria detachedCriteria){ 8EOh0gk7
Integer count = (Integer) n'THe|:I
9/#0?(K8
getHibernateTemplate().execute(new HibernateCallback(){ 1o8wy_eSs
publicObject doInHibernate rvW!7-R
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(Session session)throws HibernateException { +}P%HH]E/p
Criteria criteria = <"<Mbbp
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detachedCriteria.getExecutableCriteria(session); M|d={o9Hp
return BWWq4mdb{
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criteria.setProjection(Projections.rowCount '!p=aF9L
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()).uniqueResult(); z<hFK+j,'^
} M&r2:Whk
}, true); LIF|bE9kd
return count.intValue(); |+98h&U~
} cgyp5\*>+
} l';pP^.q
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用户在web层构造查询条件detachedCriteria,和可选的 nP<S6:s:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 K}x_nW
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PaginationSupport的实例ps。 _3/ec]1
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ps.getItems()得到已分页好的结果集 NetYg]8`
ps.getIndexes()得到分页索引的数组 #b'N}2'p#V
ps.getTotalCount()得到总结果数 %,/lqc Fo
ps.getStartIndex()当前分页索引 N>0LQ
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ps.getNextIndex()下一页索引 k'Gw!p}
ps.getPreviousIndex()上一页索引 %<ic%gt`#
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} ~| k
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6gnbkpYi
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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 Z0-ytODII
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一下代码重构了。 >)NQH9'1
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我把原本我的做法也提供出来供大家讨论吧: eJHp6)2
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首先,为了实现分页查询,我封装了一个Page类: mk%b9Ko<F
java代码: f8=]oa]
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/*Created on 2005-4-14*/ oaK.kOo
package org.flyware.util.page; JEhm1T
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/** Zsj`F9*e
* @author Joa e`iEy=W
* : lgi>^
*/ Ow@v"L;jF!
publicclass Page { )1lu=gc
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/** imply if the page has previous page */ ^
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privateboolean hasPrePage; ^/toz).Q
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/** imply if the page has next page */ hJf2o
privateboolean hasNextPage; E=AVrv5T
jZd}OC<
/** the number of every page */ 'N\&<dT>
privateint everyPage; E)W@{?.o#
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/** the total page number */ 9 |{%i$
privateint totalPage; d]SYP
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/** the number of current page */ b*EXIzQ
privateint currentPage; r8[T&z@_
GS;%zdH~
/** the begin index of the records by the current x GH1epf
)*|(i]
query */ 8md*wEjk
privateint beginIndex; &^!h}D%T/
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/** The default constructor */ <??umkV
public Page(){ 6o=G8y
gl8Ib<{
} Q`ME@vz
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/** construct the page by everyPage q/PNJ#<
* @param everyPage ^A9M;q
* */ p=Y>i 'CG
public Page(int everyPage){ ;b0NGa(k
this.everyPage = everyPage; ;a
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} Elb aFbr
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/** The whole constructor */ O=}g4c
public Page(boolean hasPrePage, boolean hasNextPage, XRtD< jlA"
'wQv3;
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int everyPage, int totalPage, D-&an@
int currentPage, int beginIndex){ "& 25D
this.hasPrePage = hasPrePage; 2S~R !
this.hasNextPage = hasNextPage; ZVih =Y-w
this.everyPage = everyPage; !<<AzLVL
this.totalPage = totalPage; Q.Aa{d9e
this.currentPage = currentPage; Kz?#C
this.beginIndex = beginIndex; 8)j@aiF`
} eE(b4RCM
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/** CvDxq:x
* @return 6RoAl$}'
* Returns the beginIndex. =qu(~]2(
*/ ru9zTZZD
publicint getBeginIndex(){ vScjq5"p
return beginIndex; r!GW=u'
} N|usFqCNk^
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/** "_1)CDqP
* @param beginIndex J G$Z.s
* The beginIndex to set. G~,:2
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*/ )[Z!*a m
publicvoid setBeginIndex(int beginIndex){ lioc`C:
this.beginIndex = beginIndex; Dw6 fmyJ:
} F3Maqr y
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/** 6.WceWBR
* @return >''U
* Returns the currentPage. A8r^)QJP{
*/ /F)H\*
publicint getCurrentPage(){ K > g[k_
return currentPage; }G
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} JRaq!/[(
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/** nz]&a1"&
* @param currentPage 0#_'o ,
* The currentPage to set. i3$$,W!
*/ fyknP)21I
publicvoid setCurrentPage(int currentPage){ 2JGL;U$
this.currentPage = currentPage; EgjR^A1W2
} XvTCK>1
hX:"QXx
/** D{8PQ2x>
* @return 3SttHu0X
* Returns the everyPage. c9"r6j2m5
*/ Of,2Q#oji
publicint getEveryPage(){ aB~S?.l
return everyPage; C1kYl0zR[
} ]=pR
/YAJbr
/** u\yVR$pQ
* @param everyPage w;6bD'.>;
* The everyPage to set. Lh.b5Q|
*/ zi9[)YqxPH
publicvoid setEveryPage(int everyPage){ g4p
this.everyPage = everyPage; ]}|byo
} 6w8">~)Z
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/** ^TY;Zp
* @return rwLAW"0Qz
* Returns the hasNextPage. B;>{0
s
*/ K<`osdp=&
publicboolean getHasNextPage(){ `F YjQe"p
return hasNextPage; !9Z r;K~\
} DyJ.BQdk)
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/** {76c%<`WaP
* @param hasNextPage Rhc-q|Lz8
* The hasNextPage to set. FY{e2~gi
*/ CC=d I
publicvoid setHasNextPage(boolean hasNextPage){ soA|wk\A
this.hasNextPage = hasNextPage; #G" xNl
} O/s$SX%g
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/** |1b_*G4|
* @return yZr M.%V
* Returns the hasPrePage. >{gPN"S"a
*/
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publicboolean getHasPrePage(){ Dl(3wgA
return hasPrePage; ^DeERB
} R0ID2:i]F
58\&/lYW
/** XR2~Q)@
* @param hasPrePage ZYU=\
* The hasPrePage to set. `*", <
*/ 6tHO!`}1
publicvoid setHasPrePage(boolean hasPrePage){ M5nWVK7c
this.hasPrePage = hasPrePage; )c n+1R
} Qd}m`YW-f$
)a9 ]US^
/** DI+]D~N
* @return Returns the totalPage. d@`M
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* JWvjWY2+P
*/ wN1niR'
publicint getTotalPage(){ |8>3`w!
return totalPage; [[PEa-992
} poGc a1
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/** ;c~cet4
* @param totalPage S#)Eom?V
* The totalPage to set. @k[R/,#'[t
*/ F<>!kK/c
publicvoid setTotalPage(int totalPage){ B~o\+n
this.totalPage = totalPage; wW>zgTG
} )[0T16
f` =CpO*
} _XJ2fA )
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&%})wZ+Dj
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 4wC+S9I#E^
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个PageUtil,负责对Page对象进行构造: /VmR<C?h
java代码: R\o<7g-|
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/*Created on 2005-4-14*/ MZ Aij
package org.flyware.util.page; z<H~ItX,n
HGm 3+,
import org.apache.commons.logging.Log; 6qcO?U
import org.apache.commons.logging.LogFactory; 9Gv[8'I
'YNT8w/3
/** ^Wxad?@
* @author Joa GKN%Tv:D_
* GpZc5c
*/ WVVJ
publicclass PageUtil { f|O{#AC
o-}R?>
privatestaticfinal Log logger = LogFactory.getLog $)3%U?AP
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(PageUtil.class); 311LC cRp
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/** w"R:\@ F
* Use the origin page to create a new page D8
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* @param page !rqF}d
* @param totalRecords ^Z~;4il_F
* @return ;&1V0U,fx
*/ 1V8-^
publicstatic Page createPage(Page page, int {?'fyEeg
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totalRecords){ N[k wO1
return createPage(page.getEveryPage(), iD<(b`S
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page.getCurrentPage(), totalRecords); `jwa<N4e@
} 7o8{mp'_
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/** os/vtyP:a
* the basic page utils not including exception [IK )
R: l&2k@
handler V}\~ugN)y
* @param everyPage @}u9Rn*d;
* @param currentPage Pp )3(T:
* @param totalRecords ?O>V%@
* @return page <=f}8a.R3
*/ H^YSJ6
publicstatic Page createPage(int everyPage, int y@\V+
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vu
currentPage, int totalRecords){ *zr(Zv
everyPage = getEveryPage(everyPage); E9;|'Vy<E
currentPage = getCurrentPage(currentPage); AhZ8 0!
int beginIndex = getBeginIndex(everyPage, N!g9*Z
tKpmm`2
currentPage); 9<KAXr#
int totalPage = getTotalPage(everyPage, `ho1nY$)CE
O%FPS=
totalRecords); S#+h$UVh
boolean hasNextPage = hasNextPage(currentPage, *4V=z#
lV%N
totalPage); hiQha5
boolean hasPrePage = hasPrePage(currentPage); V7/I>^X
aG^4BpIP
returnnew Page(hasPrePage, hasNextPage, iezO9`
everyPage, totalPage, gG/!,Q.Qh
currentPage, fMOU$0]$<
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beginIndex); 9(@\&>)
} fl\ly`_
#-bA[eQV
privatestaticint getEveryPage(int everyPage){ TA{\PKA)
return everyPage == 0 ? 10 : everyPage; g1jTy7g?
} ~Q\3pI. |
8 XU1/i7N
privatestaticint getCurrentPage(int currentPage){ 1Z9qjV%^
return currentPage == 0 ? 1 : currentPage; >yULC|'F&~
} Z,=7Tu bR#
Y 'ow
privatestaticint getBeginIndex(int everyPage, int B[KJR?>
aoXb2 2]{
currentPage){ B'fb^n<
return(currentPage - 1) * everyPage; l,kUhZ@W
} 5O\*h;U 6
3g >B"t
privatestaticint getTotalPage(int everyPage, int a[ex[TRKe
,G2TVjz
totalRecords){ uuQ(&
int totalPage = 0; o93`|yWl
0zi~p>*nJC
if(totalRecords % everyPage == 0) $C `;fA
totalPage = totalRecords / everyPage; >(;{C<6|^
else /oriW;OF
totalPage = totalRecords / everyPage + 1 ; ;72T|e
gXjV?"^kUl
return totalPage; <kCU@SK
} 3? HhG
\Cii1\R=
privatestaticboolean hasPrePage(int currentPage){ }5hqDBK?
return currentPage == 1 ? false : true; (2=Zm@Zpf
} kO}AxeQ
?:)]h c
privatestaticboolean hasNextPage(int currentPage, ?O8ViB?2
9M:O0) s
int totalPage){ cZ|\.0-
return currentPage == totalPage || totalPage == nX=$EQiH
f`[R7Q5
0 ? false : true; BG<q IQd
} Y*14v~\'
T3^GC X|!@
^_f+15]D
} + ~>Aj
*FM Mjz
|6$p;Aar
0:T|S>FsAm
}nL7T'$>
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。 &sU?Ok6
t{.8|d@
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 H XmS|PX
FAj)OTI2S
做法如下: 'L8'
'(eZ^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }&[
i(NdGL#P
的信息,和一个结果集List: fP.
6HF_p_
java代码: sNLs\4v
aXoVy&x=
jJ5W>Q1mK$
/*Created on 2005-6-13*/ [Lzw#XE
package com.adt.bo; oomT)gO 6*
4B^ZnFJ%m
import java.util.List; } x2DT8u
fc
|GArL#}
import org.flyware.util.page.Page; aL&n[
FGoy8+nB1M
/** _iir<}
* @author Joa zlEX+=3
*/ v^1pN>#%g
publicclass Result { BDjn
!3
fP(d8xTx2y
private Page page; m+Rv+_R
K[!&b0O
private List content; [_Qa9e
#N`~xZ|$
/** *exS6@N]
* The default constructor e8GEoD
*/
K~| 4[\
public Result(){ L{8xlx`
super(); E6pMT^{K
} 9T*v9d
FSA1gAW6g
/** '7iSp=
* The constructor using fields )3>hhuaa
* {qN 5MsY
* @param page %'X[^W
* @param content D"a~#^
*/ |v({-*7
public Result(Page page, List content){ /!3@]xz*
this.page = page; PEW=@xj2y
this.content = content; 'LE=6{#
} }n4V|f-
#~<0t(3Q
/** (aH'h1,G
* @return Returns the content. 9R7A8
*/ z}MP)|aH:
publicList getContent(){ /,g ,Ch<d
return content; r(RKwr:m
} z{o'
G3
lc~%=
/** d2H|LMhJ
* @return Returns the page. T Kg aV;92
*/ rV T{90,
public Page getPage(){ ,}K7Dg^1
return page; 61)-cVC
} *q-['"f
UOxkO
/** ;{KV /<3
* @param content Z|lqb=
* The content to set. |bO"_U
*/ f)^_|8
public void setContent(List content){ 5
4L\Jx
this.content = content; ]zWon~
} 4X+ifZO
V 7Ek-2M
/** iqe%=%ZR
* @param page V4KMOYqm
* The page to set. 4*Hgv:0?kI
*/ 0 g?z&?
publicvoid setPage(Page page){ '|Kmq5)
this.page = page; .O0+H+
} pQtJc*[!
} wfq7ob4^
/#m=*&!CB
&L,nqc\3D5
O8j_0
)'6DNa[y
2. 编写业务逻辑接口,并实现它(UserManager, t+1 %RyKFB
TjwBv6h
UserManagerImpl) ^$'z!+QRM
java代码: p IU&^yX>
.ZJRO>S
k[:bQ)H
/*Created on 2005-7-15*/ <U!`J[n%
package com.adt.service; 4Za7^c.
{;:/-0s
import net.sf.hibernate.HibernateException; IHcD*zQ
9mmCp&~Z
import org.flyware.util.page.Page; ucG@?@JENm
6 1F(<!
import com.adt.bo.Result; 93`
AWg/T
3v5%y'
/** X;"Sx#U
* @author Joa >JC
*/ {ZI)nQ{
publicinterface UserManager { ^]W<X"H+Z
{6_|/KE9_
public Result listUser(Page page)throws --|Wh^i>?
WYEKf9}
HibernateException; k6sI
L3QJ0
}Du}c3
} 'i4_`^:+
,Qe?8En[
tm#nU w
/Q2mMSK1h
Q=/</|
java代码: :$m}UA-9
(}EB2V9Hh
L.jh
/*Created on 2005-7-15*/ xx{PespNt
package com.adt.service.impl; O4^8jK}
t ]_VG
import java.util.List; Pyb Z)5u
LRb{hUt=
import net.sf.hibernate.HibernateException; p%*%n3bw
A<qTg`gA
import org.flyware.util.page.Page; xK6n0] A
import org.flyware.util.page.PageUtil; I~Zh@d%
w6{TE(]zp
import com.adt.bo.Result; Y[$!`);Ye
import com.adt.dao.UserDAO; \8?Tdx=
import com.adt.exception.ObjectNotFoundException; .xH5fMj,"
import com.adt.service.UserManager; 83Q4On
(+FfB"3]
/** GJtZ&H
* @author Joa &'}RrW-s
*/ 17G'jiYH
publicclass UserManagerImpl implements UserManager { O0pDd4)"
d[V;&U
private UserDAO userDAO; b{]z
wpf
Dm-zMCf}Q
/** I/L_@X<*r
* @param userDAO The userDAO to set. 7w/4QiI
*/ pnbIiyV
publicvoid setUserDAO(UserDAO userDAO){ wT:b\km:!
this.userDAO = userDAO; t-0a7
1#e
} -<
&D
L&%s[
/* (non-Javadoc) !VI]oRgP
* @see com.adt.service.UserManager#listUser DIzH`|Y
b+&%1C
(org.flyware.util.page.Page) |qmu_x\
*/ gm[z[~X@
public Result listUser(Page page)throws {yB&xj[z
aM:nOt" S1
HibernateException, ObjectNotFoundException { $l|qk z
int totalRecords = userDAO.getUserCount(); HLZ;8/|48m
if(totalRecords == 0) U~j
^I^
throw new ObjectNotFoundException 0QOBL'{7)
W^]3XJP
("userNotExist"); 'zGo?a
page = PageUtil.createPage(page, totalRecords); 8@2OJ =`[
List users = userDAO.getUserByPage(page); p~,]*y:XT
returnnew Result(page, users); kAC&S!n
} (r D_(%o
yGPS`S
} ^]a #7/]o
P:aJ#
.sj^{kGE
d
BJJZ^(
U2wbv Xr5-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 L"j
tf78
< !dqTJos
询,接下来编写UserDAO的代码: yRfSJbzaf\
3. UserDAO 和 UserDAOImpl: KjE+QUa
java代码: *Ie7{EhJ'
$+3}po\
0Pe>Es|^A#
/*Created on 2005-7-15*/ W>p-u6u%E|
package com.adt.dao; /O^RF }
7El[ >
import java.util.List; t[oT-r
ZObhF#Y9
import org.flyware.util.page.Page; t{WzKy
O2BDL1o
import net.sf.hibernate.HibernateException; LM-J !44
hijgF@
/**
GrAujc5|
* @author Joa pn.T~"%
*/ `/ q|@B7
publicinterface UserDAO extends BaseDAO { ,J{ei7TN
f1 _<G
publicList getUserByName(String name)throws OI0;BBZ
d~`x )B(
HibernateException; s+EAB{w$
Gmq/3tw
publicint getUserCount()throws HibernateException; m$W <
S!3S4:]B^
publicList getUserByPage(Page page)throws NZ-\h
p-zXp K"
HibernateException; [vHv0"
/Ya_>+oo
} NCk r /#!
U]vYV
z3K6%rb-
.D:Z{|.1
Z<SLc,]^
java代码: JA'h4AXk
]b%Hy
P3nb2.
/*Created on 2005-7-15*/ N.]qU d
package com.adt.dao.impl; 8qu2iPOcZ
}=6'MjF]
import java.util.List; 0VGPEKRh
L_+k12lm
import org.flyware.util.page.Page; k'IYA#T6
R@6zGZ1
import net.sf.hibernate.HibernateException; jlBanGs?
import net.sf.hibernate.Query; Y))u&*RuT0
`9uB~LY^i
import com.adt.dao.UserDAO; k25WucQ
#&m0WI1
/** o;=l^-
* @author Joa dUF&."pW e
*/ 7"w2$*4 '0
public class UserDAOImpl extends BaseDAOHibernateImpl 3`B6w$z>(
n ;$5Cq!v=
implements UserDAO { ?kZTI (
{FIXc^m'
/* (non-Javadoc) %QKRFPYhS
* @see com.adt.dao.UserDAO#getUserByName k-HCeZ
:)_~w4&
(java.lang.String) l*kPOyB
*/ Zuw?58RE\
publicList getUserByName(String name)throws AQ+]|XYo_
_-9@qe
HibernateException { ?}RSwl
String querySentence = "FROM user in class 6C]1Q.f;
u9}1)9
com.adt.po.User WHERE user.name=:name"; B]Y}Hu
Query query = getSession().createQuery bV8!"{
jGEt+\"/QJ
(querySentence); D!.+Y-+Xzu
query.setParameter("name", name); P~G 1EK|4
return query.list(); Fx
$Q;H!.
} f"9q^
oA =4=`
/* (non-Javadoc) qd#sY.|1
* @see com.adt.dao.UserDAO#getUserCount() p"FW&Q=PN
*/ }*ZHgf]~#
publicint getUserCount()throws HibernateException { )~+ e`q
int count = 0; tvu!< dxZ
String querySentence = "SELECT count(*) FROM E7CH^]x
Wo7F
user in class com.adt.po.User"; >OG:vw)E
Query query = getSession().createQuery phn9:{TI
&s$(g~ 4gC
(querySentence); .GsO.#p{
count = ((Integer)query.iterate().next ;B?DfWX
\L(*]:EP
()).intValue(); #DN0T' B
return count; 9uer(}WKT
} cu% C"
H]$)Eg%6
/* (non-Javadoc) lNL6M%e$Q
* @see com.adt.dao.UserDAO#getUserByPage 't_[dSO
;Ww7"-=sw
(org.flyware.util.page.Page) ??i,Vr@)w
*/ Q<KvBgmT
publicList getUserByPage(Page page)throws z j/!In
~5 *5
HibernateException { 3q'&j,,^
String querySentence = "FROM user in class rc/nFl6#
8:#rA*Y
com.adt.po.User"; Pp|*J^U 4
Query query = getSession().createQuery ;Wl+zw
*_KFW@bC:
(querySentence); ,Vh{gm1
query.setFirstResult(page.getBeginIndex()) ^ mS
o1?<
.setMaxResults(page.getEveryPage()); |6(ZD^w
return query.list(); B"v.*
%"&/
} KGWyJ
9(L)&S{4K
} s.x&LG
L
W;heO"
{O,{c\
Uv?|G%cD-
EloMe~a3
至此,一个完整的分页程序完成。前台的只需要调用 OzQ -7|m'J
]Lm9^q14m
userManager.listUser(page)即可得到一个Page对象和结果集对象 7yx$Nn`(
>A<bBK#
的综合体,而传入的参数page对象则可以由前台传入,如果用 #Ap;_XcKw
5i-Rglo
webwork,甚至可以直接在配置文件中指定。 OI?K/rn
ph_4q@
下面给出一个webwork调用示例: 7yz4'L
java代码: Vm df8[5
n':! ,a[
pFm=y#!t
/*Created on 2005-6-17*/ $ KRI'4
package com.adt.action.user; y8 KX<2s1
KMV=%o
import java.util.List; +]|Z%;im
9&2Vm;F_
import org.apache.commons.logging.Log; V~hlq$jn<Y
import org.apache.commons.logging.LogFactory; PZm:T+5H
import org.flyware.util.page.Page; PNA\ TXT
\T\b NbPn
import com.adt.bo.Result; 2{Chu85
import com.adt.service.UserService; IZm(`b;t^
import com.opensymphony.xwork.Action; ^m/oDB-
>(<ytn t=
/** Hsihytdj
* @author Joa !j\" w p
*/ :gB[O>'<m
publicclass ListUser implementsAction{ !TP@-
X;
yY&3p1AxW]
privatestaticfinal Log logger = LogFactory.getLog R-RDT9&<
:mS# h@l
(ListUser.class); 3"kdjOB
9Li%KOY
private UserService userService; `iJhG^w9M
fsEzpUY:{W
private Page page; h@@nR(<i
eXkujjSw"
privateList users; (__yh^h:m
7;tJK^J`
/* !bD@aVf?5
* (non-Javadoc) >rP#ukr5
* X!j{o
* @see com.opensymphony.xwork.Action#execute() g
>'p>}t
*/ v|ck>_"
.
publicString execute()throwsException{ oP2fX_v1x
Result result = userService.listUser(page); )'hH^(Yu
page = result.getPage(); dDD<E?TjD
users = result.getContent(); #9m$ N
return SUCCESS; 3GmeD/6
} %',F
qA:#iJ8w
/** O0:)X)b
* @return Returns the page. ~-#yOu
,w
*/ C'!;J
public Page getPage(){ tdEnk.O
return page; 37q@rDm2
} ~+H"
-+
-3&G"hfK
/** K YkS9_yF
* @return Returns the users. i `0v#P
*/ t9_E$w^U
publicList getUsers(){ mCz,2K|^~
return users; ph}j[Co
} 8$c bVMjh
DS2)@
/**
/q@s
* @param page G|m1.=DJm
* The page to set. {i*2R^5
*/ KZbR3mi,
publicvoid setPage(Page page){ 3loY qeP
this.page = page; ?,=f\Fz!
} ycJg%]F*5
tj*y)28-
/** ;oNhEB:F
* @param users gUR]{dq^'
* The users to set. LrCk*@
*/ '&FjW-`"
G
publicvoid setUsers(List users){ 7Mx6
this.users = users; +"ueq
} cM&2SRBZ
Q*YYTmZ
/** @f!AkzI
* @param userService ^#):c`
* The userService to set. vMs;>lhtg
*/ ,WQ^tI=O
publicvoid setUserService(UserService userService){ =l9T7az
this.userService = userService; &W6^6=E{g
} k{AyD`'Q
} Pz_NDI
tQ~W EC
\]Dt4o*yZ
I<=Df5M
&48_2Q"{
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, 7dX/bzUVz8
rxO2js
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 AY SSa 1}
+<.\5+
么只需要: -#29xRPk
java代码: w#
*1 /N
XMRNuEU
Z?^"\u-
<?xml version="1.0"?> `*\{.;,]#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork .9|uQEL
3_`szl-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l12$l<x&M
(X6sSO
1.0.dtd"> ~JuKV&&}K
S)A'Y]2X
<xwork> 3|rn] yZ
(vJ2z
=z
<package name="user" extends="webwork- R[1BfZ 6s
me\cLFw
interceptors"> {6d b{ ay_
-Y:ROoFOZ
<!-- The default interceptor stack name DJQglt}~
8@M'[jT
--> N8!TZ~1$
<default-interceptor-ref S^f:`9ab9
]]cYLaq(
name="myDefaultWebStack"/> eeUp 1g
ze'.Y%]
<action name="listUser" fA^7^0![
5]jIg<j
class="com.adt.action.user.ListUser"> `BnP[jF
<param {BO|u{C
W3Ulewa
name="page.everyPage">10</param> b>~RSO*
<result XNH4==4
VG*'"y*%w
name="success">/user/user_list.jsp</result> sFb4`
</action> 3]n0 &MZAR
{*/dD`
</package> )9P&=
C;a@Jjor'
</xwork> >Jm"2U}lZW
4?/7
bc
c Cxi{a1uo
aEx(rLd+
idJh^YD
"]t>ZT:OJ
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 nd+?O7~}(
}`9`JmNM
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。 C$#W{2x%6
16@);Ot
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 w}M3x^9@
^C9x.4I$)
G5{Ot>;*%
[BBpQN.^q6
(3md:r<-
我写的一个用于分页的类,用了泛型了,hoho P 4;{jG
&.*uc|{
java代码: agaq`^[(P
7CrpUh
o@dy:AR
package com.intokr.util; H/+{e,SW"
wq4nMY:#
import java.util.List; * Zd_
HJi
_2jw,WKr
/** z };ZxN
* 用于分页的类<br> kb|eQtH
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Qg0vG]
* " OGdE_E
* @version 0.01 IMad$AKc
* @author cheng d.pp3D9/
*/ A/Khk2-:
public class Paginator<E> { wO"GtVd
privateint count = 0; // 总记录数 i<u9:W
privateint p = 1; // 页编号 *?8RXer
privateint num = 20; // 每页的记录数 )&.!3y 660
privateList<E> results = null; // 结果 j
0
Y
+AK:(r
/** /84bv=
* 结果总数 <pOl[5v]
*/ yL"i
publicint getCount(){ #'>?:k
return count; S!7g)
} iMWW%@U^=
\$;~74}
publicvoid setCount(int count){ Z5>V{o
this.count = count; j,t~
} Lp~^*j(
b~W)S/wF$P
/** 8^w/HCC8O
* 本结果所在的页码,从1开始 \|Qb[{<:,
* ,QS'$n
* @return Returns the pageNo. ,#aS/+;[)
*/ 6+8mV8{-8
publicint getP(){ \/,g VT
return p; BPWnck=%
} d_iY&-gq/
J v<$*TVS0
/** Ofm5[q=
* if(p<=0) p=1 ]xR4->eix
* sA\L7`2H
* @param p M@O2
WB1ws
*/ sPpS~wk*
publicvoid setP(int p){ |yAK@Hl'
if(p <= 0) 9-G b"hr
p = 1; aQmfrx
this.p = p; =xBT>h;
} hwDXm9
p!GZCf,
/** MOyT< $
* 每页记录数量 k ZK//YN#
*/ Uk02IOXQ
publicint getNum(){ ?48AY6
return num; !
IgoL&=
} b8HE."*t
U"B.:C2
/** Vr\Q`H.
* if(num<1) num=1 M@~o6 ^
*/ 7O461$4v
publicvoid setNum(int num){ 4OEKx|:5n
if(num < 1)
0dh#/
num = 1; N<"`ShCNM
this.num = num; %|jzEBz@
} Oc^m_U8>^
6oA~J]<
/** 1C'P)f28
* 获得总页数 Wo2v5-
*/ &<=e_0zT
publicint getPageNum(){ `A"Q3sf%
return(count - 1) / num + 1; A:c]1
} ixzTJ]y u
nFj-<!
/** -? Tz.y&
* 获得本页的开始编号,为 (p-1)*num+1 3]_qj*V
*/ 'f6PjI
publicint getStart(){ /B=l,:TnJ
return(p - 1) * num + 1; (h|ch#
} =Pj@g/25u
s@z{dmL
/** Ym:{Mm=ud
* @return Returns the results. s<d!+<
*/ KJ pj
publicList<E> getResults(){ Y.9~Bo<<r
return results; !Z-9tYO
} u/#&0_
P
;'hi9L
public void setResults(List<E> results){ Lb^(E-
this.results = results; jjX%$Hr
} ,{pGP#
"SLvUzO>q
public String toString(){ `1$y( w]
StringBuilder buff = new StringBuilder 5=m3J!?
T aEt
(); k}-]W@UCa?
buff.append("{"); ]xI?,('_m
buff.append("count:").append(count); W8x[3,gT
buff.append(",p:").append(p); v#-E~;CcC
buff.append(",nump:").append(num); @?Fx
buff.append(",results:").append ^ePsIl1E
Fj,(_^
(results); /_HwifRQ
buff.append("}"); d>;2,srUf
return buff.toString(); hMz&JJ&B
} ) (+)Q'*
}R`Irxv4
} 2H3(HZv
K Ka c6Zj
-}< d(c