Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v2X>%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 wNzALfS
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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 p'#
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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 3=r#=u5z
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分页支持类: !nX}\lw
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java代码: Wz}DC7
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package com.javaeye.common.util; gWlv;oq
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import java.util.List; 'FVh/};Y.D
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publicclass PaginationSupport { :Bk!YK
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publicfinalstaticint PAGESIZE = 30; G-5wv
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privateint pageSize = PAGESIZE; bwHl}3
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privateList items; 6O|B'?]Pf
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privateint totalCount; d=?Kk4Ag
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privateint[] indexes = newint[0];
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privateint startIndex = 0; j Wa%vA
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public PaginationSupport(List items, int |$$gj[+^
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totalCount){ [(%6]L}
setPageSize(PAGESIZE); >FrF"u:kM
setTotalCount(totalCount); +f#oij
setItems(items); ,mpvGvAI
setStartIndex(0); =P* YwLb
} \FVm_)
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public PaginationSupport(List items, int x 6=Yt{
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totalCount, int startIndex){ Gp}:U>V)
setPageSize(PAGESIZE); #;4afj:2g
setTotalCount(totalCount); Z0fl]3p
setItems(items); K|"97{*|2
setStartIndex(startIndex); UG)XA-ez
} a[Q\8<
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public PaginationSupport(List items, int gEWKM(5B}
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totalCount, int pageSize, int startIndex){ QfLDyJv`e
setPageSize(pageSize); &4g]#A >@
setTotalCount(totalCount); !8cS1(a
setItems(items); >]6inS9
setStartIndex(startIndex); N$Pi4
} 1J(` kQ)c
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publicList getItems(){ #bFJ6;g=V
return items; I/whpOg
} yJ(BPSt
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publicvoid setItems(List items){ x3X^\Ig
this.items = items; RTHe#`t
} z(-j%?
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publicint getPageSize(){ v0~'`*|&
return pageSize; wUnz D)
} SONv]));
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publicvoid setPageSize(int pageSize){ n|G x29E
this.pageSize = pageSize; Y}G 9(Ci&
} ]p,svevo
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publicint getTotalCount(){ bnso+cA
return totalCount; W(5et5DN,
} `# N j8
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publicvoid setTotalCount(int totalCount){ jacp':T
if(totalCount > 0){ Dgb@`oo
this.totalCount = totalCount; *2K/)(
int count = totalCount / O$'BJKj-4
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pageSize; v' x)AbbC
if(totalCount % pageSize > 0) ^lF'KW$
count++; s7x&x;-
indexes = newint[count]; 'X()|{
for(int i = 0; i < count; i++){ f-w-K)y$ht
indexes = pageSize * XkG:1H;Q%
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} ,\HZIl[8
}else{ J$9`[^pV
this.totalCount = 0; 3^ct;gz
} %kod31X3<
} xJ/<G$LNJ0
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publicint[] getIndexes(){ \0K3TMl)J
return indexes; H9@24NFb
} ; O6Ez-"
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publicvoid setIndexes(int[] indexes){ ~EYsUC#B_
this.indexes = indexes; yuTSzl25,/
} br@GnjG
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publicint getStartIndex(){ 3M 5+!H
return startIndex; K>!+5A$6i
} NJ^H"FLS:
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publicvoid setStartIndex(int startIndex){ 2ZZ%BV!s
if(totalCount <= 0) j. @CB`
this.startIndex = 0; f!3$xu5
elseif(startIndex >= totalCount)
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this.startIndex = indexes 1@xmzTC
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[indexes.length - 1]; z0@{5e$#Y
elseif(startIndex < 0) oWJ0>)
this.startIndex = 0; ,Z2fVz~9
else{ k&|#(1CFY
this.startIndex = indexes GFq,Ca~
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[startIndex / pageSize]; :\]TAQd-
} T^"-;
} 6c[&[L%
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publicint getNextIndex(){ gpIq4Q<
int nextIndex = getStartIndex() + .u+ZrA#
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pageSize; ,'7 X|z/_>
if(nextIndex >= totalCount) -y@#
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return getStartIndex(); 4pYscB
else %K9 9_Cl3
return nextIndex; K2'Il[
} 1
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publicint getPreviousIndex(){ P(n_eIF-f
int previousIndex = getStartIndex() - OMl<=;^:|
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pageSize; NCid`a$
if(previousIndex < 0) il=:T\'U9
return0; E46+B2_~zk
else JO|%Vpco
return previousIndex; xI'sprNa_1
} DlD;rL=
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} iSiez'
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抽象业务类 G_5uO58
java代码: ^lI>&I&1
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/** bu}N{cW
* Created on 2005-7-12 X(YR).a~
*/ cft'% IEs
package com.javaeye.common.business; >Y3ZK{b
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import java.io.Serializable; j'2:z#
import java.util.List; s-S#qGZ
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import org.hibernate.Criteria; {.,-lFb\
import org.hibernate.HibernateException; +NM`y=@@
import org.hibernate.Session; 3Z taj^v
import org.hibernate.criterion.DetachedCriteria; )2&U
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import org.hibernate.criterion.Projections; ['`Vg=O.{
import h'wI
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org.springframework.orm.hibernate3.HibernateCallback; qm!&(8NfK
import ?y1G,0,
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org.springframework.orm.hibernate3.support.HibernateDaoS {Rd){ky@
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upport; F\)?Ntj)>@
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import com.javaeye.common.util.PaginationSupport; ZcP/rT3{^
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public abstract class AbstractManager extends *(w#*,lv
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HibernateDaoSupport { `~+1i5-}
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privateboolean cacheQueries = false; WxgA{q7:
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privateString queryCacheRegion; ;7
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publicvoid setCacheQueries(boolean JX $vz*KF
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cacheQueries){ 1(nK |
this.cacheQueries = cacheQueries; ]b&"](A
} vz87]InI
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publicvoid setQueryCacheRegion(String d i;Fj
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queryCacheRegion){ u3VSS4RG%
this.queryCacheRegion = ^! r<-J
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queryCacheRegion; W "}Cfv
} A4|L;z/A[h
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publicvoid save(finalObject entity){ m})EYs1
getHibernateTemplate().save(entity); @D3|Ak 1
} 0|L%)'F
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publicvoid persist(finalObject entity){ c]OK)i-{l
getHibernateTemplate().save(entity); KhWt9=9
} sf(2~BMQI
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publicvoid update(finalObject entity){ bS2)L4MQY
getHibernateTemplate().update(entity); $I$ B8
} V=+wsc
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publicvoid delete(finalObject entity){ )e|n7|} $
getHibernateTemplate().delete(entity); w~lxWgaY7
} aR@s.
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publicObject load(finalClass entity, wq6.:8Or-]
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finalSerializable id){ IMF9eS{L
return getHibernateTemplate().load 'xn3g ;5
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(entity, id); 8
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} m0$~O5|4
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publicObject get(finalClass entity, l`M7a9*U
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finalSerializable id){ zmEg4 v'I
return getHibernateTemplate().get ^5- 8'9 w
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(entity, id); ~A-1x!YiU
} M<KWx'uV
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publicList findAll(finalClass entity){ :TTZ@ q
return getHibernateTemplate().find("from u@ psVt
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" + entity.getName()); Scfk]DT
} 6Y 4I $[
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publicList findByNamedQuery(finalString o$[alh;c+W
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namedQuery){ '_`O&rbT
return getHibernateTemplate &|j^?ro6
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().findByNamedQuery(namedQuery); :Dn{
} Pd^v-}[
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publicList findByNamedQuery(finalString query, Y{v\m(D
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finalObject parameter){ to%n2^^K
return getHibernateTemplate y G{;kJ P
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().findByNamedQuery(query, parameter); x[w!buV0\
} kNnI$(H"H
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publicList findByNamedQuery(finalString query, %Q2<bj]
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finalObject[] parameters){ __Tg1A
return getHibernateTemplate 3u g-cq
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().findByNamedQuery(query, parameters); =Kh1HU.F
} '
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publicList find(finalString query){ D3MRRv#
return getHibernateTemplate().find h,u?3}Knnb
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(query); }-8ZSWog6f
} z:+fiJB_
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publicList find(finalString query, finalObject re-;s
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parameter){ FLE2]cL-
return getHibernateTemplate().find ='"hB~[
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(query, parameter); 61"w>;d6
} QT\=>,Fz _
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public PaginationSupport findPageByCriteria 2&+Nr+P
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(final DetachedCriteria detachedCriteria){ UW?(-_8
return findPageByCriteria FO/[7ZH
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); (aQNe{D#
} F=qG+T
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public PaginationSupport findPageByCriteria `Zm-F
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(final DetachedCriteria detachedCriteria, finalint PAUepO_
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startIndex){ Ld?-Ik~fF>
return findPageByCriteria P
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(detachedCriteria, PaginationSupport.PAGESIZE, Oz:J8l%
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startIndex); J_H=GHMp}
} 0M=U>g)
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public PaginationSupport findPageByCriteria k m(Mv
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(final DetachedCriteria detachedCriteria, finalint l^$8;$Rq
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pageSize, @2>j4Sc
finalint startIndex){ a1 I"Sh
return(PaginationSupport) c2aW4TX2
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getHibernateTemplate().execute(new HibernateCallback(){ vj?6,Ae
publicObject doInHibernate o_K.
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(Session session)throws HibernateException { AusCU~:>
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); 3ZF- n`
int totalCount = EC]b]'._
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((Integer) criteria.setProjection(Projections.rowCount =y>g:}G7
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()).uniqueResult()).intValue(); %nmD>QCe
criteria.setProjection PZDj)x_%B&
}!W,/=z*
(null); <![]=~z$
List items = k!^Au8Up?
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criteria.setFirstResult(startIndex).setMaxResults -S ASn
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(pageSize).list(); n&51_.@Q
PaginationSupport ps = +a{P,fRl@
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new PaginationSupport(items, totalCount, pageSize, $eI=5
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startIndex); RO]Vn]qb
return ps; z&3in
} 4^KeA".
}, true); vp4l g1/
} ?_!} lg
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public List findAllByCriteria(final w=]bj0<A=
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DetachedCriteria detachedCriteria){ u Z(vf
return(List) getHibernateTemplate uh][qMyLM
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().execute(new HibernateCallback(){ {GTOHJ2
publicObject doInHibernate M_5$y)M
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(Session session)throws HibernateException { tML[~AZh
Criteria criteria = UX?EOrfJ
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detachedCriteria.getExecutableCriteria(session); vp"b_x1-
return criteria.list(); SnK#YQCDt
} *~t&Ux#hj
}, true); ^F>C|FJ2
} Y[hTO.LF
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public int getCountByCriteria(final U]aH4N
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DetachedCriteria detachedCriteria){ GW]b[l
Integer count = (Integer) }#~DX!Sj
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getHibernateTemplate().execute(new HibernateCallback(){ sS 5aJ}Qs
publicObject doInHibernate l"I
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(Session session)throws HibernateException { zNF.nS}:
Criteria criteria = Znv3h
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detachedCriteria.getExecutableCriteria(session); d)_fI*:f
return w?r
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criteria.setProjection(Projections.rowCount rF/k$_bFt
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()).uniqueResult(); ^#-i%V%
} )_m#|U?Rex
}, true); zNZ"PYh<u
return count.intValue(); Kx-s95t
} jkzC^aG
} Uz;z
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用户在web层构造查询条件detachedCriteria,和可选的 0R#T 3K}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u?ALZxj?
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PaginationSupport的实例ps。 I6q]bQ="
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ps.getItems()得到已分页好的结果集 o
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ps.getIndexes()得到分页索引的数组 ?qdZ]M4e
ps.getTotalCount()得到总结果数 |#87|XIJ&~
ps.getStartIndex()当前分页索引 L\CufAN
ps.getNextIndex()下一页索引 \Y>!vh X
ps.getPreviousIndex()上一页索引 l]bCt b%_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 qoifzEc`U
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 }'"4q
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一下代码重构了。 zFR=inI
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我把原本我的做法也提供出来供大家讨论吧: y[pU8QSt
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首先,为了实现分页查询,我封装了一个Page类: 3BTXX0yx
java代码: 4X()D {uR
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/*Created on 2005-4-14*/ SEL7,8 Hm
package org.flyware.util.page; bnm3
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/** 8|*=p4_fn
* @author Joa !,I530eh7
* aDae0$lc.S
*/ P ]prrKZe,
publicclass Page { f`[gRcZ-
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/** imply if the page has previous page */ F1q a`j^'
privateboolean hasPrePage; kY$vPHZpN
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/** imply if the page has next page */ 0Xke26ga
privateboolean hasNextPage; /.Fvl;!J;
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/** the number of every page */ PXH"%vVF
privateint everyPage; w<4,;FFlZ/
*1>zE>nlP
/** the total page number */ C4`u3S
privateint totalPage; _F"o0K!u
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/** the number of current page */ <f')]
privateint currentPage; 9uRs@]i
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/** the begin index of the records by the current Z,? T`[4B
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query */ f"wm]Q59
privateint beginIndex; OFyZY@B-C~
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/** The default constructor */ qXb{A*J
public Page(){ HoFFce7o
m V U(b,
} tR;? o,T
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/** construct the page by everyPage h
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* @param everyPage D+y_&+&,t
* */ x;G~c5
public Page(int everyPage){ !aVwmd'9
this.everyPage = everyPage; ,IODV`L
} LvtZZX6!
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/** The whole constructor */ w'Cn3b)`
public Page(boolean hasPrePage, boolean hasNextPage, Dn}Wsd=
upJ|`,G{
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int everyPage, int totalPage, RZV8{
int currentPage, int beginIndex){ @aA1=9-L
this.hasPrePage = hasPrePage; -quWnn/
this.hasNextPage = hasNextPage; CQLh;W`Dc
this.everyPage = everyPage; XO=UKk+EK
this.totalPage = totalPage; R
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this.currentPage = currentPage; @k ~_ w#
this.beginIndex = beginIndex; l9 K 3E<g
}
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/** N1O& fMz
* @return s`bC?wr5h
* Returns the beginIndex. Rilr)$
*/ ~4{E0om@
publicint getBeginIndex(){ T}?vp~./
return beginIndex; 4/Vy@h"A3
} zW@OSKq4
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/** ,r,~1oV<"
* @param beginIndex BBub'
* The beginIndex to set. L?@TF;
*/ n(mS
publicvoid setBeginIndex(int beginIndex){ cI5*`LML1
this.beginIndex = beginIndex; K{
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} CKAs3",
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/** )P{I<TBI;
* @return >};6>)0
* Returns the currentPage. r "^{?0
*/ [":[\D'
publicint getCurrentPage(){ ~dIb>[7wy
return currentPage; LNp%]*h
} dh7PpuN{
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/** ZOFhX$I
* @param currentPage S=Ihg
* The currentPage to set. L"i
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*/ `0r=ND5.
publicvoid setCurrentPage(int currentPage){ + *YGsM`E9
this.currentPage = currentPage; @17hB h
} 2p( M`@
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/** 23/!k}G"
* @return zS Yh ?NB5
* Returns the everyPage. 1}E`K#
*/ #]s>
publicint getEveryPage(){ Ozk^B{{o
return everyPage; L3Leb%,!
} :E|HP#iwu
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/** b$sw`Rsw
* @param everyPage #vy:aq<bjE
* The everyPage to set. ]P TTI\n
*/ rK*s/mX <
publicvoid setEveryPage(int everyPage){ 28[dTsd%
this.everyPage = everyPage; xMsos?5}
} o~
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/** ]McLace&
* @return ]1 #& J(
* Returns the hasNextPage. EXDtVa Ot
*/ ?~rF3M.=|
publicboolean getHasNextPage(){ s-eC' )w~E
return hasNextPage; 0s = h*"[
} 5_+vjV;5
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/** 4#uWj?u
* @param hasNextPage PsDks3cG
* The hasNextPage to set. c=l
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*/ (Rvke!"B
publicvoid setHasNextPage(boolean hasNextPage){ Wh%qvV6]
this.hasNextPage = hasNextPage; SGW2'
} {&G7 Xa
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/** %t0Fx
* @return R@``MC0
* Returns the hasPrePage. ?;.j)
*/ V *=To
publicboolean getHasPrePage(){ X75>C<
return hasPrePage; DCb\=E
} ze
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/** YzU(U_g$
* @param hasPrePage ;YxQo
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* The hasPrePage to set. )2}{fFa%
*/ 2
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publicvoid setHasPrePage(boolean hasPrePage){ TH2D ;uv
this.hasPrePage = hasPrePage; .+7GecYz
} :g3n
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/** (LPMEQhI:
* @return Returns the totalPage. P}o:WI4.cB
* lIO.LF3
*/ R2Fh
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publicint getTotalPage(){ [7?K9r\#
return totalPage; KyW6[WA9
} 22|eiW/a
H,qIHQW#
/** hGcq>Cvf
* @param totalPage #d%'BUde
* The totalPage to set. fGJPZe
*/ k
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publicvoid setTotalPage(int totalPage){ 3ik
this.totalPage = totalPage; 4VPL
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} @`aR*B
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} $rDeI-)S
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 /Dj6Bj
}
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个PageUtil,负责对Page对象进行构造: ,v:m
java代码: ,FX;-nP%
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/*Created on 2005-4-14*/ C$\|eC j
package org.flyware.util.page; nnIBN4
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import org.apache.commons.logging.Log; ;rpjXP
import org.apache.commons.logging.LogFactory; 9@Yk8
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/** b9[;qqq@'
* @author Joa &^4\Rx_I
* L5""
*/ Kxz<f>`b/
publicclass PageUtil { 6
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privatestaticfinal Log logger = LogFactory.getLog H
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*. l,_68
(PageUtil.class); O^hWG ~o
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/** bCg
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* Use the origin page to create a new page z71.5n!C
* @param page `?{QCBVj
* @param totalRecords (E59)z -
* @return )I{41/_YA
*/ /HgdTyR)
publicstatic Page createPage(Page page, int Adgh:'h
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totalRecords){ OBi9aFoQ
return createPage(page.getEveryPage(), _)Q)tOW
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page.getCurrentPage(), totalRecords); M hNzmI&`
} %5RY Ea
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/** ,K .P,z~*
* the basic page utils not including exception xn1
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handler vGO- a2Z
* @param everyPage Y8`4K* 58%
* @param currentPage k_#ra7zP
* @param totalRecords -EFtk\/
* @return page 64>E|w
*/ jDIO,XuF
publicstatic Page createPage(int everyPage, int |Y"q. n77
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currentPage, int totalRecords){ Rtw^
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everyPage = getEveryPage(everyPage); _Xd,aLoo
currentPage = getCurrentPage(currentPage); AU} e^1h
int beginIndex = getBeginIndex(everyPage, \v{tK;
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currentPage); Q+)fI
int totalPage = getTotalPage(everyPage, rA&|!1q"B
mf6?8!O}>
totalRecords); aB"W6[
boolean hasNextPage = hasNextPage(currentPage, MFcN.M
XP
*pYN
totalPage); Q^/66"Z:Z
boolean hasPrePage = hasPrePage(currentPage); CFAz/x@%
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returnnew Page(hasPrePage, hasNextPage, [c]X)
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everyPage, totalPage, #o_`$'>
currentPage, OEy'8O$
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beginIndex); vC[)/w
} #sdW3m_%
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privatestaticint getEveryPage(int everyPage){ :.f =>s]
return everyPage == 0 ? 10 : everyPage; pa Uh+"y>
} } WY7!Y
#K'3`dpL
privatestaticint getCurrentPage(int currentPage){ c 6@!?8J
return currentPage == 0 ? 1 : currentPage; N,V%/O{Y
} :XEr{X
D`0II=
privatestaticint getBeginIndex(int everyPage, int 5c($3Pno=
q3JoU/Sf
currentPage){ EC$wi|i
return(currentPage - 1) * everyPage; p}_bu@;.Z
} {^>m3
JYOyz+wNd
privatestaticint getTotalPage(int everyPage, int +"6_rbeuO
!L:!X88
totalRecords){ /lkIbmV
int totalPage = 0; HT)b3Ws~M8
]Gm,sp.x
if(totalRecords % everyPage == 0) }"wWSPD
totalPage = totalRecords / everyPage; B5*{85p(u
else +b1(sk=4z
totalPage = totalRecords / everyPage + 1 ; xcwyn\93)
K/79Tb-
return totalPage; (h7 rW3
} HiCNs;t
o{pQDI {R
privatestaticboolean hasPrePage(int currentPage){ _$PZID
return currentPage == 1 ? false : true; ,n TC7V
} 'm}K$h(U
ZW }*]rg
privatestaticboolean hasNextPage(int currentPage, y _M<\b
]24aK_Uu
int totalPage){ zM"OateA
return currentPage == totalPage || totalPage == R8P7JY[h
&G7JGar
0 ? false : true; ?Z
{4iF
} B-ReBtN
)+RTA
y [k
N[d*_KN.!
} [
\ LA
f;`pj`-k%
dX{|-;6vm
N~_GJw@
&!]$#
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。 ^qs=fF
7)!(0.&
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 K#H}=Y A
:&}(?=<R}L
做法如下: 7SLJLn3d
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Ac'[(
7tMV*{+Z
的信息,和一个结果集List: u$$@Hw
java代码: 5:/
zbt\C
I!&|L0Qq
)9MmL-7K
/*Created on 2005-6-13*/ T^g2N`w2
package com.adt.bo; rM#jxAb
K@Q_q/(%;
import java.util.List;
H_m(7@=
]c]rIOTN
import org.flyware.util.page.Page; asb-syqU
*,5V;7OR
/** <uDEDb1|l
* @author Joa w'z?1M(*
*/ #y%bx<A
publicclass Result { ]+;1)
0ohpJh61Q
private Page page; )$Xd#bzD|
A9\m.3jo
private List content; Y,?s-AB
Ks.m5R
/** u"XqWLTV
* The default constructor ^
}Rqe
*/ A|1
TE$
public Result(){ /uS(Z-@
super(); e}y oy+9
} r,X5@/
z=:<]j#=
/** -jnx0{/
* The constructor using fields F%@(
$f
* RX8$&z
* @param page 4V9DPBh
* @param content WL$Ee=
*/ {i y[8eLg
public Result(Page page, List content){ 3XdN\xc
this.page = page; @-nCK Yj
this.content = content; 7;RhA5M
} SO%x=W
:L#t?~
/** j@1cllJkh
* @return Returns the content. eWzD'3h^
*/ #Ki(9oWd
publicList getContent(){ x=Z\c,@O
return content; n_\VG[f
} U<{8nMB
RpPbjz~
/** .|
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* @return Returns the page. BTjfzfO"
*/ 8"/5Lh(
public Page getPage(){ }ozlED`E
return page; ;> **+ezF
}
/B)ZB})z
3-#|6khqt
/** O9*cV3}H
* @param content ss63/
* The content to set. O4@sN=o
*/ hNs970i
public void setContent(List content){ D,%R[F?5O
this.content = content; g\;AU2?p7
} 3kFSu
l0AgW_T
/** Ry>c]\a]
* @param page @r4ZN6Wn
* The page to set. z2Sp
*/ {vYmK#}
publicvoid setPage(Page page){ Dz/I"bZLC
this.page = page; jV
Yt=j*"V
} So; ;
} T)wc{C9w
?Q1(L$-=
g.OBh_j-v
&EKP93
WF\
hXO
2. 编写业务逻辑接口,并实现它(UserManager, Xr\|U89P
1;cV [&3
UserManagerImpl) le*mr0a
java代码: uU(G &:@
6OR5zXpk
S6-)N(3|
/*Created on 2005-7-15*/ @k:f(c
package com.adt.service; 9z7^0Ruw
%^s;{aN*!
import net.sf.hibernate.HibernateException; aiVd^(
&09z`*,
import org.flyware.util.page.Page; V_f}Y8>e
#PUvrA2Zl
import com.adt.bo.Result; Uf)?sz
dA>=#/"
/** 9n{tbabJ
* @author Joa hZ2!UW4'
*/ F{}mlQg
publicinterface UserManager { iTsmUq<b]l
Qj: D=j8
public Result listUser(Page page)throws '7G'R
h-
.V[]<
HibernateException; 3qOq:ZkQ
(7BG~T
} qS<a5 `EA
mqgA
m^cr-'
W5,e;4/hL
T|^rFaA
java代码: jqq96hP,
4zuM?Dp
tiG=KHK%o
/*Created on 2005-7-15*/ *A C){M
package com.adt.service.impl; cF!ygz//
=ic"K6mhq
import java.util.List; KrE:ilm#^Y
K +n
import net.sf.hibernate.HibernateException; 4cJ7W_ >i6
Cj31>k1
import org.flyware.util.page.Page; ?B
;+,
import org.flyware.util.page.PageUtil; G)5w_^&%
ZN>oz@jY
import com.adt.bo.Result; hZNS$
import com.adt.dao.UserDAO; 7=C$*)x
import com.adt.exception.ObjectNotFoundException; *izPLM}+
import com.adt.service.UserManager; *sK")Q4N
kKr|PFz
/** I>ks H
* @author Joa X`bN/sI
*/ 1A\Jh3;Q
publicclass UserManagerImpl implements UserManager {
i zJa`K
mh`~1aEr
private UserDAO userDAO; Eukj2a
)RA$E`!b
/** QX}O{LQR
* @param userDAO The userDAO to set. v0euvs
*/ ,E,oz {,i(
publicvoid setUserDAO(UserDAO userDAO){ *,qW9z
this.userDAO = userDAO; S <~"\<ED
} X,VOKj.%
U-/-aNJ]U
/* (non-Javadoc) @+II@[_lT
* @see com.adt.service.UserManager#listUser iu!j#VO
x+Vp&
(org.flyware.util.page.Page) 1SIhW:C
*/ }T=0]u4,
public Result listUser(Page page)throws S9kagiFX\
8a{S*
HibernateException, ObjectNotFoundException { BeP]M1\?>
int totalRecords = userDAO.getUserCount(); q#9JJWSs
if(totalRecords == 0) 9sYN7x
throw new ObjectNotFoundException `s
HrC
ZuZe8&
("userNotExist"); yZ?|u57
page = PageUtil.createPage(page, totalRecords); I4'mU$)U
List users = userDAO.getUserByPage(page); N8a+X|3]0
returnnew Result(page, users); p6~\U5rXm
} Pd-0u>k
W,&z:z>
} P.^%8L
UHr0J jQK
y4* }E
3LXS}~&
*s4h tt
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 57r?`'#*
bxX[$q
询,接下来编写UserDAO的代码: &w\E*$
3. UserDAO 和 UserDAOImpl: I2G4j/c=z
java代码: 9W{`$30
LASR*
.)Xyzd
/*Created on 2005-7-15*/ g/H:`J
package com.adt.dao; <vS J<WY
b+/XVEsr
import java.util.List; -I."= c%
N"-</kzV
import org.flyware.util.page.Page; !GJnYDN
!YD~o/t@|
import net.sf.hibernate.HibernateException; &"!s +_
qMy>:,)Z
/** cRYnQ{$'
* @author Joa CBaU$`5
*/ Gvg)@VNr
publicinterface UserDAO extends BaseDAO { J9s4lsea
vY|{CBGbd
publicList getUserByName(String name)throws wX(h]X"q
paFiuQ
HibernateException; nNuv 0
A y ?;0w0
publicint getUserCount()throws HibernateException; T}DP35dBzE
r9!jIkILz
publicList getUserByPage(Page page)throws E"LSM]^^<f
3Z?"M
HibernateException; @C[]o.r
Y1e>P
} !uaV6K
6ww4ZH?j
k.Tu#7
P%#WeQ+
Yphru"\$
java代码: 1rs`|iX5
nNb Oq[
RmXC
^VQ
/*Created on 2005-7-15*/ R7~H}>uaF
package com.adt.dao.impl; E]G#"EV!Y
?UD2}D[M
import java.util.List; k-5Enbkr
0*?/s\>PS;
import org.flyware.util.page.Page; EW;R^?Z
a.P7O!2Lp
import net.sf.hibernate.HibernateException; ` fw:
import net.sf.hibernate.Query; )b<-=VR
z[xi
import com.adt.dao.UserDAO; MQD%m ;[s
i3C5"\y
/** K9JW&5Q
* @author Joa x!6&)T?!n
*/ U@#YKv
public class UserDAOImpl extends BaseDAOHibernateImpl =4RXNWkud
x13t@b
implements UserDAO { 8r7}6
u= a5Z4 N'
/* (non-Javadoc) }e}J6[wP
* @see com.adt.dao.UserDAO#getUserByName H(qDQqJHYy
W<Ms0
(java.lang.String) 7:fC,2+
*/ f{ZOH<"Lo
publicList getUserByName(String name)throws 4;G:.k!K
:?1r.n
HibernateException { XXbAn-J
String querySentence = "FROM user in class Jw%0t'0Zi
88 fH!6b
com.adt.po.User WHERE user.name=:name"; {XC1B
Query query = getSession().createQuery |\g =ua+h
W/*2I3a
(querySentence); b"U{@
query.setParameter("name", name); $umh&z/
return query.list(); WfbG }%&J
} Y02 cX@K6
SKT f=rY
/* (non-Javadoc) 5<o8prtB
* @see com.adt.dao.UserDAO#getUserCount() >T*/[{L8;
*/ U68o"iE
publicint getUserCount()throws HibernateException { lR5<
G
int count = 0; W n*>h'R
String querySentence = "SELECT count(*) FROM +5n,/YjS`
xO8-vmf2
user in class com.adt.po.User"; :1Jg;G
Query query = getSession().createQuery #{973~uj
Xg>nb1e
(querySentence); R"Q=U}?$
count = ((Integer)query.iterate().next \x JGR!
.h)o\6Wq
()).intValue(); uyr56
return count; 9
yH/5'
} <gU^#gsGra
X"V,3gDG
/* (non-Javadoc) ImJ2tz6
* @see com.adt.dao.UserDAO#getUserByPage P,xI3U<
q
A%H" a+
(org.flyware.util.page.Page) ICSi<V[y1
*/ $$E!u}
publicList getUserByPage(Page page)throws 2{!o"6t
&A=>x
HibernateException { Fb#_(I[aj
String querySentence = "FROM user in class wLeP;u1
8l(_{Y5(-
com.adt.po.User"; fVCpG~&t
Query query = getSession().createQuery w_-v!s2
}S{#DgZ@X
(querySentence); RhVQVj c
query.setFirstResult(page.getBeginIndex()) 8BUPvaP<[
.setMaxResults(page.getEveryPage()); cx?XJ)
return query.list(); 'gYUyl
} |2mm@):
3OUZR5_$
} ><odBM-
#7S[Ch}O
ZJev_mj
l4c9.'6
ur\v[k=
至此,一个完整的分页程序完成。前台的只需要调用 Sp+ zP-3
~9.0:Fm<
userManager.listUser(page)即可得到一个Page对象和结果集对象 HorFQ?8
C[h"w'A2
的综合体,而传入的参数page对象则可以由前台传入,如果用 (<f`},
QxD
Y`@:L'j
webwork,甚至可以直接在配置文件中指定。 <u\j4<p
jOs&E^">&B
下面给出一个webwork调用示例: B%95M|
java代码: x:bJ1%
o"F=3b~:n
1`1U'ibhe
/*Created on 2005-6-17*/ H.sHXuu
package com.adt.action.user; JTuU}nm+
{"<D$*K~
import java.util.List; vu^ '+ky
9pN},F91n:
import org.apache.commons.logging.Log; `]L&2RS
import org.apache.commons.logging.LogFactory; 69)- )en
import org.flyware.util.page.Page; 8c-r;DE
<Wgp$qt;
import com.adt.bo.Result; $5XE'm
import com.adt.service.UserService; >3R)&N
import com.opensymphony.xwork.Action; 2y6 e]D
ml=tS,
/** Ew>E]Ys
* @author Joa
?LU]O\p
*/ {ETuaFDM
publicclass ListUser implementsAction{ *n$=2v^A
2"`R_q
privatestaticfinal Log logger = LogFactory.getLog OgpZwwk
}E626d}uA
(ListUser.class); [R$iX
G}B)bM2
private UserService userService; aw
z(W>
s!*m^zx
private Page page; |l)z^V!
o+e:HjZZ
privateList users; };5d>#NK,Y
dTN[E6#R
/* H$2<N@'4z
* (non-Javadoc) - inZX`afA
* Wr.G9zq.+
* @see com.opensymphony.xwork.Action#execute() tz#Fy?pe
*/ 6?an._ C
publicString execute()throwsException{ .(T*mk*>
Result result = userService.listUser(page); #l kv&.)x
page = result.getPage(); IbFS8 *a\
users = result.getContent(); [=dK%7v
return SUCCESS; WEgJ_dB
} &jJj6
+P\
$j?zEz
/** ~gz_4gzb
* @return Returns the page. @VlDi1
*/ (~6oA f
public Page getPage(){ !g=2U`j^
return page; I<p- o/TP
} Z(F`M;1>xI
JHN{vB
/** N"A863>
* @return Returns the users. g"pjWj)?
*/ 6_KO6O7g
publicList getUsers(){ {9>LF
return users; 0s>ozAJ
} l]
-mdq/C
l423+vo
/** 5Oh>r K(
* @param page Uy$1X
* The page to set. y7a84)j3
*/ i8CO+Iv*{
publicvoid setPage(Page page){ 4hRc,Vq
this.page = page; *}mk$bA
} cj=6_k
|$AoI
/** 6Z2a5zO8
* @param users "UUzLa_
* The users to set. ;JQ:S~K9
*/ q]}fW)r
publicvoid setUsers(List users){ ;onhc*{lv
this.users = users; h+,Eu7\88
} %kB84dE
}@R*U0*E
/** .d}7c!
* @param userService jIpc^iu`,
* The userService to set. eiTG
*/ $^[^]Q
publicvoid setUserService(UserService userService){ J0{;"
this.userService = userService; i@Vi.oc4[
} QfHJZ7K.4
} >x/;'Y.
s/' ]* n
v[P
$c$Xi
puE!7:X7
'JA<q-Gn
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, nQy %av$
)SJ18 no|l
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 Ft} h&aYP
?4G/f<ou
么只需要: >fX_zowX
java代码: 9Tju+KcK
/EW1&
tQTVP 2:Y
<?xml version="1.0"?> Gp&o
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Vifh`BSP
g!<=NVhYt
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;:2:f1_
aaa6R|>0
1.0.dtd"> Z4@%0mFll
&\w:jI44Bs
<xwork> ^)\z
S.iCkX
<package name="user" extends="webwork- *Fb|iR
@nPXu2c?u7
interceptors"> eaNMcC1
R]Iv?)Y
<!-- The default interceptor stack name 3W<_J_[
[\41
--> 86_`Z$ s
<default-interceptor-ref C71\9K*X
yu^n;gWH
name="myDefaultWebStack"/> "2J$~2{N
Hi V7
<action name="listUser" `Z)]mH\X
,lsoxl
class="com.adt.action.user.ListUser"> /*$B
<param N^Bjw?3
[pAW' :
name="page.everyPage">10</param> ,m"0Bu2
<result v; =|-y
hoJ{C 0
name="success">/user/user_list.jsp</result> @'D ,T^I
</action> -D?-ctFYj^
ZSs)AB_Pe/
</package> /8$*{ay
?WD JWp%
</xwork> =r?#,'a
W.|r=
o?T01t=
z8n=\xL
A7eF.V&
0\/cTNN
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 7QnQ=gu
h#EksX
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。 Pr>Pxs r&
>I*Qc<X91
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 *{#l0My
O /S: S
czp .q
K1*oYH B
y?r:`n
我写的一个用于分页的类,用了泛型了,hoho vc r5
/a'cP
java代码: I7[F,xci
JsDugn ,B
e
[}m@a
package com.intokr.util; BZdryk:S
|^&j'k+A
import java.util.List; $t1XoL
mh5ozv$
/** +6i~Rx>
* 用于分页的类<br> 7K.in3M(
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0QakFt
* =xf7lN'
* @version 0.01 i!tF{'*%#
* @author cheng $h)VKW^\
*/ I7Uj<a=(q
public class Paginator<E> { K]bw1KK
privateint count = 0; // 总记录数 S2!$
privateint p = 1; // 页编号 Q*GJREC
privateint num = 20; // 每页的记录数 >^U$2P
privateList<E> results = null; // 结果 2)W~7GED
sy
s6 V?
/** Ie<`WU K
* 结果总数 p%?VW
*/ /&T"w,D
publicint getCount(){ ophQdJM
return count; gPA),
NrN
} |IgH0
zZ
l+V#`S*q
publicvoid setCount(int count){ h^`!kp
this.count = count; R,
J(]ew
} doj$chy
>axf_k
/** L<`p;?
* 本结果所在的页码,从1开始 ;OTd<
* piy_9nk
* @return Returns the pageNo. ;FI"N@z
*/ kv)IG$S0
publicint getP(){ <z2*T \B!8
return p; #$dk
} MU-T>S4
\{Yi7V
Xv
/** .dr-I7&!
* if(p<=0) p=1 "j]85
* QEb
^'y
* @param p O0i)Iu(J7;
*/ .w@o%AO_
publicvoid setP(int p){ dh;
L!
if(p <= 0) B0&W wa:
p = 1; /Ayo78Pi
this.p = p; >E:V7Fa
} AfV
a[{E
Pv>W`/*_,s
/** $QbaPmHW
* 每页记录数量 zdh&,!] F6
*/ "F.0(<4)
publicint getNum(){ YR\pt8(z?
return num; $v#\bqY
} VEtdp*ot
MD62ObK!
/** =;!$Qw4
* if(num<1) num=1 jJ B+UF=
*/ =MP?aH
[
publicvoid setNum(int num){ ;%/Kh :Vg
if(num < 1) b;AGw3SF
num = 1; e2@{Ab
this.num = num; M|l`2Hpe
} > 0kZ-M5
q7!$-
/** Oosr`e@S
* 获得总页数 k|-P&g
*/ :K#z~#n
publicint getPageNum(){ C'a%piX
return(count - 1) / num + 1; p3N/"t&>
} 6')pM&`t
XLeQxp=
/** L+rMBa
* 获得本页的开始编号,为 (p-1)*num+1 ZWVN(U
*/ kg@Okz N%
publicint getStart(){ ;YYo^9Lh}
return(p - 1) * num + 1; )uJu.foE
} O`pqS\H
,$xV&w8f\"
/** )T_o!/\*|*
* @return Returns the results. Jh)x_&R&Q
*/ e=yQFzQT)
publicList<E> getResults(){ ?f{--|V
return results; , '_y@9?I
} Xc!0'P0T
Z fQzA}QD
public void setResults(List<E> results){ uq~Z
this.results = results; :|P[u+v
} Tw{}Ht_Qq
v_7?Zik8E
public String toString(){ VPAi[<FzOG
StringBuilder buff = new StringBuilder eMDO;q
5ml#/kE
(); YaWZOuxm
buff.append("{"); ST*\ Q
buff.append("count:").append(count); #KOr-Yg|U
buff.append(",p:").append(p); LZ?z5U:
buff.append(",nump:").append(num); *G6Py,- !f
buff.append(",results:").append Vo@gxC,
^V1iOf:
(results); aT[qJbp1
buff.append("}"); -!~T$}/F
return buff.toString(); I>(3\z4s
} ^)| !nd
]V4Fm{]
} KO ~_
:L E&p[^
a(qij&>