Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XC;Icr)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 n6t@ e^
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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 U$OI]Dd9
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 K^@9\cl^
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分页支持类: g"|>^90
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java代码: L~;(M6Jp
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package com.javaeye.common.util; AIn/v`JeX
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import java.util.List; z7AWWr=H
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publicclass PaginationSupport { <B0f
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publicfinalstaticint PAGESIZE = 30; M!i|,S
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privateint pageSize = PAGESIZE; NZ i3U
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privateList items; "OwVCym?
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privateint totalCount; :8oJG8WH
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privateint[] indexes = newint[0]; (?t}S.>g
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privateint startIndex = 0; of_y<dd[G
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public PaginationSupport(List items, int dTK0lgkUE
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totalCount){ 8Vj'&UY
setPageSize(PAGESIZE); # >bj6<
setTotalCount(totalCount); :EQ{7Op`
setItems(items); 7_ayn#;y
setStartIndex(0); p)iEwl}!j
} MomHSv Q\
, p~1fB-/
public PaginationSupport(List items, int `ROHB@-
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totalCount, int startIndex){ Kd^.>T-
setPageSize(PAGESIZE); yCN_vrH>
setTotalCount(totalCount); [H<TcT8
setItems(items); /QyKXg6)l
setStartIndex(startIndex); G'G8`1Nj
} Wpl/CO5z
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public PaginationSupport(List items, int xR3$sA2
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totalCount, int pageSize, int startIndex){ uz{RV_IX7
setPageSize(pageSize); jci,]*X4
setTotalCount(totalCount); hF0,{v
setItems(items); oS..y($TI
setStartIndex(startIndex); io+V4m
} ]nB|8k=J
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publicList getItems(){ u>:(MARsR
return items; @
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} ;H~<.QW
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publicvoid setItems(List items){ ~o%igJ
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this.items = items; xH*X5?
} ;mk[!
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publicint getPageSize(){ \_8wU'7
return pageSize; xxu
} jO&*E'pk
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publicvoid setPageSize(int pageSize){ 3)W zX
this.pageSize = pageSize; h5@GeYda
} u7[}pf$}
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publicint getTotalCount(){ w(6n
return totalCount; X^ Is-[OvE
} V9v20iX
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publicvoid setTotalCount(int totalCount){ TMj;NSc3
if(totalCount > 0){ I!S Eb
this.totalCount = totalCount; !>`Fg>uy
int count = totalCount / DpgTm&}-
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pageSize; R03 Te gwA
if(totalCount % pageSize > 0) G7nhUg
count++; [ncK+rGAc
indexes = newint[count]; !&rd#ZBn
for(int i = 0; i < count; i++){ =,(TP
indexes = pageSize * MY@&^71i4
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i; rR#Ditn^
} U;MXiE3D
}else{ erUYR"
this.totalCount = 0; 9KXL6#h
} :h{uZ,#Gi
} ^'V :T Y
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publicint[] getIndexes(){ ~_D.&-xUF
return indexes; ?@.v*'qR
} @m#OhERv
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publicvoid setIndexes(int[] indexes){ Fye>H6MU
this.indexes = indexes; ;ItH2Lw<&
} K"0IW A
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publicint getStartIndex(){ {?H5Pw>{%h
return startIndex; wu)+n\mt'
} 5 aA*
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publicvoid setStartIndex(int startIndex){ Kp`{-dUf
if(totalCount <= 0) 5.9<g>C
this.startIndex = 0; C1k< P
elseif(startIndex >= totalCount) L"m^LyU
this.startIndex = indexes QJVbt
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[indexes.length - 1]; X/,)KTo7
elseif(startIndex < 0) Y &Cb
this.startIndex = 0; >[fu&r1
else{ ef7{D
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this.startIndex = indexes x=oV!x
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[startIndex / pageSize]; SMX]JZmH
} N,Eap KG
} hO=L|BJ?I
. 5(YL8d
publicint getNextIndex(){ c1yRy|
int nextIndex = getStartIndex() + I,{YxY[$7
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pageSize; LjI`$r.B
if(nextIndex >= totalCount) X8$i*#D
return getStartIndex(); `x[Is$
else 6O7s^d&K
return nextIndex; Wo1xZZ
} 4dX{an]Cz
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publicint getPreviousIndex(){ 8=`L#FkRp
int previousIndex = getStartIndex() - ).SJ*Re*^I
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pageSize; KewW8H~tb
if(previousIndex < 0) X4
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return0; AE0uBv
else ~L)~p%rbi
return previousIndex; fMUcVTFe
} lG7PM^Eb
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} Y[{:?i~9,
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抽象业务类 vI{aF-
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java代码: (pxH<k=Ah
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/** )+G"57p
* Created on 2005-7-12 vMT f^V
*/ V`Cyx^P
package com.javaeye.common.business; tbFAVGcAM
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import java.io.Serializable; sQJ\{'g
import java.util.List; ]r
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import org.hibernate.Criteria; _U s"
import org.hibernate.HibernateException; F]\
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import org.hibernate.Session; t'n@yX_
import org.hibernate.criterion.DetachedCriteria; 3UZd_?JI[^
import org.hibernate.criterion.Projections; x-BU$bx5
import I/O3OD
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org.springframework.orm.hibernate3.HibernateCallback; mUBy*.
import 2q~.,vpP
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org.springframework.orm.hibernate3.support.HibernateDaoS XF!L.' zH
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upport; $.PRav
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import com.javaeye.common.util.PaginationSupport; Rx-\B$G
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public abstract class AbstractManager extends |N)Ik8
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HibernateDaoSupport { %HUex
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privateboolean cacheQueries = false; fAsb:P
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privateString queryCacheRegion; (RddR{mX
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publicvoid setCacheQueries(boolean &jE\D^>ko
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cacheQueries){ Cv**iW
this.cacheQueries = cacheQueries; g)Lf^
} /ZvP.VW&
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publicvoid setQueryCacheRegion(String V]7/hN-Y}
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queryCacheRegion){ .shi?aWm
this.queryCacheRegion = zI`I
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queryCacheRegion; bb6x} jR
} (GJtTp~2C4
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publicvoid save(finalObject entity){ OoB|Eh|),
getHibernateTemplate().save(entity); eZ'8JU]
} L'+bVP{L
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publicvoid persist(finalObject entity){ 6/UOzV,[
getHibernateTemplate().save(entity); `Fd
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} GA^hev
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publicvoid update(finalObject entity){ R"B{IWQi
getHibernateTemplate().update(entity); 'S`l[L:.8
} uNyU]@R<W
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publicvoid delete(finalObject entity){ c!EA>:;(<
getHibernateTemplate().delete(entity); V*vQNPey
} -S sgW
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publicObject load(finalClass entity, *u},(4Qf
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finalSerializable id){ f:>y'#P
return getHibernateTemplate().load }z`x-(V
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(entity, id); \|PiQy*_?
} C QkY6
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publicObject get(finalClass entity, irt9%w4"
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finalSerializable id){ <ToS&
return getHibernateTemplate().get B/agW
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(entity, id); yGa0/o18!?
} (?z?/4>7<
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publicList findAll(finalClass entity){ 4 &bmt
return getHibernateTemplate().find("from 7:4c\C0
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" + entity.getName()); XZE(& (s
} G5}_NS/
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publicList findByNamedQuery(finalString )D8op;Fn
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namedQuery){ JwG(WLb:
return getHibernateTemplate U0&myj 8L
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().findByNamedQuery(namedQuery); X=QX9Ux?^
} #Vk?
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publicList findByNamedQuery(finalString query, )!8qJQD
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finalObject parameter){ pDS[ecx
return getHibernateTemplate 2yfU]`qN
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.
().findByNamedQuery(query, parameter); 6z\!lOVjb
} a 0SZw
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publicList findByNamedQuery(finalString query, q{w|`vIb
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finalObject[] parameters){ <*5S7)]BP
return getHibernateTemplate wB)y@w4k
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().findByNamedQuery(query, parameters); gj^)T_E_
} 7KgaXi3r
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publicList find(finalString query){ 7y
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return getHibernateTemplate().find hz/mNDE]
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(query); [ja^Bhu
} Oo|JIr7i
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publicList find(finalString query, finalObject Ii0\Skb
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parameter){ u62H+'k}F
return getHibernateTemplate().find 8a6.77c
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q
(query, parameter); \(Ma>E4PNU
} gC$_yd6m
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public PaginationSupport findPageByCriteria By1Tum+I1
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(final DetachedCriteria detachedCriteria){ \&F4Wl>`
return findPageByCriteria +$C9@CZM9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); pA8bFtt
} CR [>5/:M
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public PaginationSupport findPageByCriteria sc*R:"
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(final DetachedCriteria detachedCriteria, finalint h,\{s_b
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startIndex){ k]ZE j/y~
return findPageByCriteria ,7V?Kj
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(detachedCriteria, PaginationSupport.PAGESIZE, ULK]' Rn
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startIndex); &4OOW;,?<
} 2/3yW.C
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public PaginationSupport findPageByCriteria .=:f]fs
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(final DetachedCriteria detachedCriteria, finalint jU-LT8y:
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pageSize, q
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finalint startIndex){ <y7{bk~i
return(PaginationSupport) db 99S
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getHibernateTemplate().execute(new HibernateCallback(){ x<I[?GT=
publicObject doInHibernate 3$"V,_TBZ
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(Session session)throws HibernateException { ZV{C9S&
Criteria criteria = {XU!p: x
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detachedCriteria.getExecutableCriteria(session); k
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int totalCount = N[eLQe]q
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((Integer) criteria.setProjection(Projections.rowCount /T6bc^nOW
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()).uniqueResult()).intValue(); X>$Wf3
criteria.setProjection $6m@gW]N
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(null); q:kGJxfaW
List items = 5&%M L
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criteria.setFirstResult(startIndex).setMaxResults $'l<2h>4
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(pageSize).list(); '=nmdqP
PaginationSupport ps = zWo
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new PaginationSupport(items, totalCount, pageSize, igL5nE=n
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startIndex); |ufT)+:
return ps; =w`Mc\o "
} 6W_:w
}, true); g@ J F
} Xr^ 5Th\
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public List findAllByCriteria(final @(L}:]{@
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DetachedCriteria detachedCriteria){ rOOo42YW`
return(List) getHibernateTemplate ]]y>d!
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().execute(new HibernateCallback(){ ItLR|LO9
publicObject doInHibernate l!}gWd,H
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(Session session)throws HibernateException { ,m*HRUY
Criteria criteria = 9+ Mj$
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detachedCriteria.getExecutableCriteria(session); > 3x^jh
return criteria.list(); $cn8]*Z=
} d7BpmM
}, true); O-[YU%K3?
} Ak3^en
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public int getCountByCriteria(final cAN8'S(s1
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DetachedCriteria detachedCriteria){ .WSn Y71
Integer count = (Integer) 41/civX>V
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getHibernateTemplate().execute(new HibernateCallback(){ Q1Qw45$
publicObject doInHibernate (,sz.
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(Session session)throws HibernateException { cFie;k
Criteria criteria = j)G%I y[`
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detachedCriteria.getExecutableCriteria(session); ax5n}
return H,<CR9@(5d
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criteria.setProjection(Projections.rowCount \>4>sCC
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()).uniqueResult(); #&uajo
} c1kV}-v
}, true); (XR}U6^v]
return count.intValue(); 1/\Xngd
} `hY%HzV=
} B (eXWWT_
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用户在web层构造查询条件detachedCriteria,和可选的 d$o m\@
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 RF8,qz
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PaginationSupport的实例ps。 &OFVqm^
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ps.getItems()得到已分页好的结果集 k~;~i)Eg
ps.getIndexes()得到分页索引的数组 1xtS$^APcd
ps.getTotalCount()得到总结果数 $Vp&7OC]
ps.getStartIndex()当前分页索引 |
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ps.getNextIndex()下一页索引 3v$n}.
ps.getPreviousIndex()上一页索引 9FC_B+7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;[lLFI
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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 ej7N5~!,s
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一下代码重构了。 AvIheR
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我把原本我的做法也提供出来供大家讨论吧: h+dk2|a
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首先,为了实现分页查询,我封装了一个Page类: s,C>l_4-
java代码: s(5(zcBK
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/*Created on 2005-4-14*/ eJ[+3Wh
package org.flyware.util.page; X`Lv}6}xT
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/** ZHwN3
* @author Joa 3>5gh8!-
* q 7W7sw
*/ V[^AV"V
publicclass Page { 1mh7fZgn
k,OxGG
/** imply if the page has previous page */ C<QpUJ`k
privateboolean hasPrePage; 7!o#pt7
ho#<?rh_
/** imply if the page has next page */ rWJRoGk/
privateboolean hasNextPage; yq2AZ@}"
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/** the number of every page */ Z[RifqaBby
privateint everyPage; pi;fu
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/** the total page number */ a~VW?wq
privateint totalPage; <vs*aFq
S"+#=C
/** the number of current page */ =%}(Dvjv
privateint currentPage; $+{o*
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/** the begin index of the records by the current L`:V]p
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query */
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privateint beginIndex; 0aGauG[
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/** The default constructor */ cy8r}wD
public Page(){ Q^Vch(`&P
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} %0u5d$b q
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/** construct the page by everyPage 8;UkZN"hy5
* @param everyPage <X5V]f
* */ KI\
9)
public Page(int everyPage){ A|mE3q=
this.everyPage = everyPage; 2*-qEUl1
} :E|+[}|
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/** The whole constructor */ 1?TgI0HS
public Page(boolean hasPrePage, boolean hasNextPage, ,F'y :px
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int everyPage, int totalPage, `]&'yt
int currentPage, int beginIndex){ "|WKK}
this.hasPrePage = hasPrePage; tnXW7ej ^
this.hasNextPage = hasNextPage; tuo'Uk)
this.everyPage = everyPage; :K \IS `
this.totalPage = totalPage; \u/=?b
this.currentPage = currentPage; A,#z_2~
this.beginIndex = beginIndex; vMXn#eR
} sWq}/!@&
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/** 3=Xvl 58k
* @return I=E\=UTG,5
* Returns the beginIndex. ;$r!eFY;
*/ s BuXwa
publicint getBeginIndex(){ z.t,qi$;{U
return beginIndex; ~a>3,v-
} X-"0Zc
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/** VM3)L>x]/
* @param beginIndex *:chN' <
* The beginIndex to set. M7gqoJM'Q
*/ m}m|(;T
publicvoid setBeginIndex(int beginIndex){ {X\FS
this.beginIndex = beginIndex; 61b<6r0o
} 'Te'wh=Y
|L)qH"Eo
/** gi/W3q3c6
* @return 5) 4?i p
* Returns the currentPage. 5e'**tbKH
*/ i,y{*xBT
publicint getCurrentPage(){ :y!{=[>M(
return currentPage; yAJrdY"
} %)r1?H} #%
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/** J
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* @param currentPage DC$x}1
* The currentPage to set. (jh0cy}|]
*/ K+U0YMRmz
publicvoid setCurrentPage(int currentPage){ cn
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this.currentPage = currentPage; ;sSRv9Xb
} *^%ohCUi
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/** `]2y=f<{X
* @return N1]P3
* Returns the everyPage. Wc/B_F?2
*/ Dd,]Y}P
publicint getEveryPage(){ C:}"?tri
return everyPage; .18MMzdN
} ];Bk|xJ/>
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/** kPp7;U2A
* @param everyPage 6)3pnhG9
* The everyPage to set. |=Pw-uk
*/ ^+dL7g?+
publicvoid setEveryPage(int everyPage){ eG5xJA^
this.everyPage = everyPage; Oyjhc<6
} eKqo6P:#f
f:A1j\A?
/** 5bprhq-7
* @return _ Av_jw`m
* Returns the hasNextPage. 4p(\2?B%f
*/ u,Cf4H*xS
publicboolean getHasNextPage(){ Z1+1>|-iW
return hasNextPage; S?(/~Vb%
} vQ
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/** lLL) S
* @param hasNextPage yKOC1( ~
* The hasNextPage to set. j1$s^ -9
*/ 2o`L^^
publicvoid setHasNextPage(boolean hasNextPage){ v1s0kdR,>
this.hasNextPage = hasNextPage; Al}%r85
} ca$K)=cDW
A!`Q[%$
/** h Qbz}x
* @return *h"7!g
* Returns the hasPrePage. bX&=*L+h6
*/ jL#`CD
publicboolean getHasPrePage(){ Bjsg!^X7
return hasPrePage; \w@ "`!%
} (,
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/** J?bx<$C@
* @param hasPrePage ,A!0:+
* The hasPrePage to set. p+1kU1F0
*/ Sa$-Yf
publicvoid setHasPrePage(boolean hasPrePage){ H_ 7E K
this.hasPrePage = hasPrePage; 'WJ3q|o/
} IdWFG?b3
0\yA6`}!
/** +Rd;>s*.Y
* @return Returns the totalPage. -f8iq[F5
* V5HK6- T
*/ ' u4TI=[6
publicint getTotalPage(){ .d%CD`8!
return totalPage; @7,k0H9Moa
} rW0-XLbL5H
|jTRIMj%,_
/** : ]~G9]R`
* @param totalPage ~myY-nEY
* The totalPage to set. 5g;i{T/6~x
*/ 6^"Spf]
publicvoid setTotalPage(int totalPage){ `-82u :"
this.totalPage = totalPage; J0x)NnWJ
} Meo.
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} D1f}g
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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 8iUj9r_
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个PageUtil,负责对Page对象进行构造: 5}"9)LT@@w
java代码: EHX/XM
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/*Created on 2005-4-14*/ jq12,R2+)
package org.flyware.util.page; JY6^pC}*
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import org.apache.commons.logging.Log; 0}I aWd^4
import org.apache.commons.logging.LogFactory; O
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/** |'N)HH>;
* @author Joa bGe@yXId5
* .V`N^H:l
*/ o0:RsODl
publicclass PageUtil { L/2,r*LNx$
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privatestaticfinal Log logger = LogFactory.getLog m>ApN@n
vKmV<*K
(PageUtil.class); %oHK=],|1
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/** Vo8gLX]a
* Use the origin page to create a new page NNP ut$.
* @param page /K\]zPq
* @param totalRecords EK$3T5e
* @return .*Ylj2nM
*/ )@[##F2
publicstatic Page createPage(Page page, int ?_nbaFQK3
gis;)al
totalRecords){ GX;~K
return createPage(page.getEveryPage(), ^n&_JQIXb
B'8/`0^n5
page.getCurrentPage(), totalRecords); V(3=j)#
} 'CA{>\F$F+
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/** &Na,D7A:3I
* the basic page utils not including exception r: M>/Z/
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handler g}n-H4LI
* @param everyPage db`L0JB
* @param currentPage XsbYWJdds
* @param totalRecords
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* @return page ME.a * v
*/ \2!1fN
publicstatic Page createPage(int everyPage, int ;Bwg'ThT
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currentPage, int totalRecords){ m< Y I}
everyPage = getEveryPage(everyPage); M2lvD&
currentPage = getCurrentPage(currentPage); FE,BvNBZ
int beginIndex = getBeginIndex(everyPage, kmT5g gy
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currentPage); pq$-s7#
int totalPage = getTotalPage(everyPage, 2rPmu
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totalRecords); M)1Y7?r]
boolean hasNextPage = hasNextPage(currentPage, }WDzzjDR+
k{ ~0BK
totalPage); TP{2q51yM
boolean hasPrePage = hasPrePage(currentPage); Wmc@:
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returnnew Page(hasPrePage, hasNextPage, VDTt}J 8
everyPage, totalPage, i8->3uB
currentPage, ,9Si3vn
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beginIndex); u N8RG_Mb
} 2mEvoWnJ
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privatestaticint getEveryPage(int everyPage){ 7!U^?0?/
return everyPage == 0 ? 10 : everyPage; `i<omZ[aT
} @|([b r|O
xM)6'= x6
privatestaticint getCurrentPage(int currentPage){ 1V.oR`&2E
return currentPage == 0 ? 1 : currentPage; ?"$Rw32
} V@rqC[on
^:~!@$*;6
privatestaticint getBeginIndex(int everyPage, int A~}5T%qb
=~_
currentPage){ U*4r<y9R
return(currentPage - 1) * everyPage; Q>(a JF
} -}(2}~{e(
l}SHR|7<
privatestaticint getTotalPage(int everyPage, int &&g02>gE
O',Vce$
totalRecords){ LyH1tF
int totalPage = 0; &P7Z_&34Z
!|\l*
if(totalRecords % everyPage == 0) 4-m6e$p;
totalPage = totalRecords / everyPage; 8PR\a!"
else L3=5tuQ[5
totalPage = totalRecords / everyPage + 1 ; Qk72ra)
+/ rt'0o
return totalPage; V]NCFG
} 2Gh&h(
lg
+ >.^7k
privatestaticboolean hasPrePage(int currentPage){ R*/s#*gmL
return currentPage == 1 ? false : true; < 1[K1'7h
} sGa}Cf;H@g
Ad&VOh+0
privatestaticboolean hasNextPage(int currentPage, $[UUf}7L
wJj:hA}
int totalPage){ LXqPNVp#
return currentPage == totalPage || totalPage == EF6h>"']/
Cxeam"-HTt
0 ? false : true; H*e +
2
} ALj~e#{;z
BP}@E$
h4#'@%
} 1mD)G55Ep
#a9O3C/MP
5;+KMM:zb
,x$^^
7=%Oev&0g-
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 .$@+ /@4
dIfy!B"
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 Y_K W9T_
m*jTvn
做法如下: Ol~M
BQs
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 l dqU#{
pH3<QNq5
的信息,和一个结果集List: PMUW<UI
java代码: *YSRZvD<\
|nE4tN#J<
/3&MUB*z&y
/*Created on 2005-6-13*/ SA7(EJ95
package com.adt.bo; Re&"Q8I.8
[Q+k2J_h
import java.util.List; L7hRFf-o
5vg="@O K
import org.flyware.util.page.Page; (zh[1[a
tva=DS
/** NBHpM}1xtU
* @author Joa C~R
?iZ.&U
*/ f,4erTBH
publicclass Result { . P+Qu
MqJ5|C.q
private Page page; t1]/Bw`j/
Vd(n2JMtG
private List content;
\ 'Va(}v
{
:1XN
/** 'ZB^=T
* The default constructor ()48> ||
*/ q
k6
public Result(){ 8CZ%-}-%$
super(); Z"RgqNf
} *~>p;*
X'-Yz7J?o
/** !|up"T I
* The constructor using fields 7f4O~4.[i
* :eSsqt9]9
* @param page &7oL2Wf
* @param content =YTcWB
*/ - Z`RKR8C
public Result(Page page, List content){ H>A6VDu
this.page = page; vENf3;o0
this.content = content; mf)+ 5On
} pQK SPr
=MMd&
/** l<BV{Gl
* @return Returns the content. !1fZ7a
*/ ),-gy~
publicList getContent(){ )Qd
x
return content; |?ssHW
} HC/z3b;
!3Pbu=(cte
/** !Av9?Q:
* @return Returns the page. r4fHD~#l{
*/ >W;NMcN~
public Page getPage(){ L- !1ybB^
return page; RQb}t,
} @1Q-.54a
Pal=I)
/** OU"%,&J
* @param content fj))Hnt(|
* The content to set. i5t6$|u:&m
*/ [d8Q AO1;)
public void setContent(List content){ RGE(#
this.content = content; {X&lgj
} p*&0d@'r
?UZt30|1
/** ?)y^ [9
* @param page +)iMJ]>
* The page to set. z8'1R6nq
*/ M{Z
;7n'
publicvoid setPage(Page page){ m$kQbPlatN
this.page = page; lOk8VlH<h
} 9MYk5q.X:
} pX
^^0
QCF'/G
!6T"J!F#
~?AEtl#&"
C=/B\G/.9
2. 编写业务逻辑接口,并实现它(UserManager, {^
b2nOMv
#uw&u6*\q
UserManagerImpl) *L$2M?xkY
java代码: Zn'tNt/
E5d$n*A
Z0jgUq`r
/*Created on 2005-7-15*/ /}(d'@8p
package com.adt.service; +t+<?M B
:q]9F4im
import net.sf.hibernate.HibernateException; ^k;]"NR
LmePJ
import org.flyware.util.page.Page; RhH1nf2UR
S@FO&o 0
import com.adt.bo.Result; eZLEdTScM
4=xi)qF/@
/** kkF)Tro\
* @author Joa ]:59c{O
*/ La;G S
publicinterface UserManager { Aw |;C
}OL"38P
public Result listUser(Page page)throws l9I r@.m
@#)` -]g
HibernateException; "y,YC M`
kg[%Q]]
} /Hyz]46
^Tm`motzh
.p&@;fZ
*h!fqT%9
_U<fS
java代码: IW3k{z
QEhn
VThr]$2Y
/*Created on 2005-7-15*/ hMDd*<%l
package com.adt.service.impl; 4^tSg#!V{
w +t@G`d
import java.util.List; hfaU-IPcFX
)U?_&LY)[M
import net.sf.hibernate.HibernateException; :"\,iH
\^c4v\s<o#
import org.flyware.util.page.Page; wZiUzS;v
import org.flyware.util.page.PageUtil; NQk aW)
GiV%Hcx
import com.adt.bo.Result; zTF{ g+
import com.adt.dao.UserDAO; O?JJE8~']
import com.adt.exception.ObjectNotFoundException; NXU:b"G
S
import com.adt.service.UserManager; 3/kT'r
}}JMwT
/** =?<WCR
C*
* @author Joa QF#w$%7
*/ 3@>F-N
publicclass UserManagerImpl implements UserManager { BBB@M
vk&
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private UserDAO userDAO; {LO Pm1K8Y
/\I6j;$z
/** ;]>kp^C#
* @param userDAO The userDAO to set. E-bswUVaEE
*/ z)qYW6o%
publicvoid setUserDAO(UserDAO userDAO){ tS'lJu
this.userDAO = userDAO; / (&E
} _FY&XL=
Fb5U@X/vE
/* (non-Javadoc) jT{T#_
* @see com.adt.service.UserManager#listUser sgX!4wG&Z
EKwQ$?I
(org.flyware.util.page.Page) I0Pw~Jj{
*/ lkn|>U[
public Result listUser(Page page)throws LVj1NP
rs&]46i/p
HibernateException, ObjectNotFoundException { 1i76u!{U
int totalRecords = userDAO.getUserCount(); n~N>;mP
if(totalRecords == 0) ]gk1q{Ql<
throw new ObjectNotFoundException ze+YQF
RP4/:sO
("userNotExist"); zUfq.
page = PageUtil.createPage(page, totalRecords); /`*{57/3
List users = userDAO.getUserByPage(page); =}^NyLE?
returnnew Result(page, users); ,XD"
p1(|G
} Jl
Do_}
>
;,S||
} -/yqiC-yx
:!`"GaTy
e
w^(3&
Mt[yY|Ec|
QU"WpkO
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -+#%]P8l
22`^Rsb,6L
询,接下来编写UserDAO的代码: Gm=qn]c
3. UserDAO 和 UserDAOImpl: 9wgB JJl7
java代码: -Zt!H%U
RZOK+!H:
WRh5v8Wz0
/*Created on 2005-7-15*/ e7vm3<m4
package com.adt.dao; ejROJXB
ALF0d|>=uj
import java.util.List; /WrB>w
J1?;'
import org.flyware.util.page.Page; 2"Os9 KD
^9g$/8[^c_
import net.sf.hibernate.HibernateException; PobX;Z
gq+SM
i=
/** 1K72}Gj)ZL
* @author Joa '0<d9OlJ}
*/ t&r.Kf9Z\
publicinterface UserDAO extends BaseDAO { $^Fl*:6
@,vmX
z
publicList getUserByName(String name)throws DD|0?i
/sE,2X*BT
HibernateException; :cT)M(o
=
tv70d'
publicint getUserCount()throws HibernateException; 4"d,=P.{
7=G2sOC
publicList getUserByPage(Page page)throws M&Uy42,MR
/x<g$!`X
HibernateException; mxa~JAlN_
*$tXm4
O[
} 3<0b_b
)DSeXS[
e
+>ju,;4WK
fqNh\~kja
[GwAm>k
java代码: pGbfdX
i! .]U@{k
DeO-@4+qKd
/*Created on 2005-7-15*/ FXQWT9Kk~_
package com.adt.dao.impl; ke4E1T-1n
LCF}Y{
import java.util.List; j]u!;]
=C"[o\]VV
import org.flyware.util.page.Page;
q6
CrUn
!b8V&<
import net.sf.hibernate.HibernateException; F'bwXb**
import net.sf.hibernate.Query; -^_m(@A<~
"F
F$Q#)
import com.adt.dao.UserDAO; _jWs(OmJ
`MtzA^X r
/** 8fC4j`!
* @author Joa OgQdyU
*/ /<LZt<K
public class UserDAOImpl extends BaseDAOHibernateImpl e~r/!B5X
XJ18(Q|w'
implements UserDAO { K$"#SZEi
UhxM85M;x
/* (non-Javadoc) MK&,2>m,A
* @see com.adt.dao.UserDAO#getUserByName u[>"_!T
(jc@8@Wo.
(java.lang.String) <2$vo
*/ y Zafq"o
publicList getUserByName(String name)throws &Mh.PzO=b
L^J4wYFTO
HibernateException { ?=u?u
k<-
String querySentence = "FROM user in class )M0YX?5AR
r`H}f#.KR
com.adt.po.User WHERE user.name=:name"; c[dSO(=
Query query = getSession().createQuery gf|uZ9{
u'YXI="(
(querySentence); [FFr}\}bY
query.setParameter("name", name); x/|W;8g4
return query.list(); 'jev1u[
} %iyc1]w{
6h 0qtXn-
/* (non-Javadoc) _`$Q6!Z)l
* @see com.adt.dao.UserDAO#getUserCount() 4TtC~#D:
*/ 3I)~;>meo
publicint getUserCount()throws HibernateException { N*Y[[N(
int count = 0; K-qWT7<
String querySentence = "SELECT count(*) FROM u]^s2v
,jU>V]YC
user in class com.adt.po.User"; GQ2GcX(E(
Query query = getSession().createQuery aZ#FKp^8H
umYsO.8
(querySentence); ]so/AdT9hA
count = ((Integer)query.iterate().next m`yvZ4K!
I
_nQTWcm
()).intValue(); "1O_h6C
return count; n,N->t$i
} i3-5~@M
2)}n"ibbT
/* (non-Javadoc) MxTJgY
* @see com.adt.dao.UserDAO#getUserByPage m\:^9A4HCg
MZgaQU g
(org.flyware.util.page.Page) YteIp'T
*/ r,5e/X
publicList getUserByPage(Page page)throws Mz@{_*2
9~SPoR/_0
HibernateException { u 3WU0Z`
String querySentence = "FROM user in class {X!vb
) CGQ}
com.adt.po.User"; =RoE=)1&-
Query query = getSession().createQuery r!r08yf
xfk
-Ezv
(querySentence); Yuv(4a<M%
query.setFirstResult(page.getBeginIndex()) tXE/aY*I
.setMaxResults(page.getEveryPage()); OC! {8MR
return query.list(); {FJMcO=
} l`v5e"V
vNO&0~
} B'Yx/c&n
TTf
j5
NdK`-RT
pb!2G/,.[
:~-:
至此,一个完整的分页程序完成。前台的只需要调用 ~OD6K`s3
]LE,4[VxRz
userManager.listUser(page)即可得到一个Page对象和结果集对象 1k[_DQ=^l1
t]xz7VQ
的综合体,而传入的参数page对象则可以由前台传入,如果用 &3vm
@
hY)zKX_r
webwork,甚至可以直接在配置文件中指定。 Q2CGC+
d59rq<yI
下面给出一个webwork调用示例: K1
f1T
java代码: kZ9Gl!g
x{H+fq,M
n:AZ(f
/*Created on 2005-6-17*/ Yy~x`P'g!
package com.adt.action.user; e$LC
^ AZ#tp%)
import java.util.List; b8!oZ~K
6
AO(A
*
import org.apache.commons.logging.Log; 2;)IBvK
import org.apache.commons.logging.LogFactory; /xn|d#4
import org.flyware.util.page.Page; {_7hX`p
@ &jR^`Y.
import com.adt.bo.Result; \kE0h\
import com.adt.service.UserService; ys=2!P-[#
import com.opensymphony.xwork.Action; FB k7Cn!
'4,?YcZ?S
/** `zoHgn7B9q
* @author Joa (Mc{nFqS
*/ !t% 1G.
publicclass ListUser implementsAction{ P|NGAd
5BrN
uR$
privatestaticfinal Log logger = LogFactory.getLog V_i&@<J
`E~"T0RX
(ListUser.class); Y3@+aA
:tWkK$
private UserService userService; PYQ0&;z
lDS y$
private Page page; "rdpA[>L
FM]clC;X?
privateList users; +|C@B`h
ch#)XomN
/* 3MQHoxX
* (non-Javadoc) FH</[7f;@N
* yLRe'5#m
* @see com.opensymphony.xwork.Action#execute() 0>[]Da}
*/ fR1LVLU
publicString execute()throwsException{
b>5*G1
Result result = userService.listUser(page); D;sG9Hky
page = result.getPage(); 0hY3vBQ!
users = result.getContent(); B9(w^l$kZ|
return SUCCESS; NSVE3
} :ok.[q
$YJ 1P
/** Mg >%EH/'
* @return Returns the page. P`rfDQoZ
*/ &D<6Go/)_*
public Page getPage(){ >p&"X 2
@
return page; &5}YTKe}|
} ]ty$/{hx'
vhZXgp0X
/** CUDA<Fm
* @return Returns the users. a3n
Wt
*/ E"}%$=yK
publicList getUsers(){ jd]L}%ax
return users; }a OBQsnO
} (o{Y;E@/y
V;^-EWNj
/** ^aqQw u
* @param page l#uF%;GDX
* The page to set. uV|F3'jT
*/ 5$
How!
publicvoid setPage(Page page){ 27}:f?2hbJ
this.page = page; ?* ~4~ZEE
} (YJ2-
X~
+wG
*qI
/** M._h=wX{}
* @param users t!4 (a0\$F
* The users to set. hq4&<Zr(
*/ P%B|HnG^
publicvoid setUsers(List users){ mN-O{k0\
this.users = users; FOD'&Yb&
} e"1mdw"
^/%o
I;O{
/** a<*+rGI
* @param userService '*[7O2\%/
* The userService to set. 5NkF_&S_1
*/ e'~Qe_
publicvoid setUserService(UserService userService){ H/t0#
this.userService = userService; aGWO3Nk
} >0 7i"a
} !UT!PX)
2V8"jc
Y"ta`+VJ
`pv
`D3q!e
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, M*'8$|Z
;\"5)S
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 5%wA"_
9t`yv@.>N
么只需要: ty[%:eG#
java代码: =ZSYg K
.NWsr*Tel
A46dtFD{
<?xml version="1.0"?> CUB;0J(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork uf]wX(*<k
PL"=>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- bv41et+Kb
9~^k3!>0
1.0.dtd"> u;%~P 9O
0rX%z$D+@
<xwork> ;7[DFlS\P
4]}d'x&
<package name="user" extends="webwork- yC@PMyE]
H.hKh
interceptors"> "#36-
` *hTx|!'
<!-- The default interceptor stack name l_((3e[)
Vh01y f
--> lB_4jc
<default-interceptor-ref nzO-\`40
QP"5A7=m
name="myDefaultWebStack"/> -^np"Jk
Rxw+`ru
<action name="listUser" @WXRZEz
"X=^MGV
class="com.adt.action.user.ListUser"> ZHwl 9n#m
<param RK*tZ
1z; !)pG.
name="page.everyPage">10</param> DZ`,QWuA
<result b L.Xby<Y
Q?.9BM1V
name="success">/user/user_list.jsp</result> iYa)*,
</action> Lcg1X3$G
I+Y Z+
</package> RYl{89
6wOj,}2Mn
</xwork> e Vj 8u
o7gZc/?n
.$f0!`
t
8\)4waz$
8~!h8bkC
dr8Q>(ZY
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 %U<lS.i
a@_n>$LZL
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 hQ)?LPUB
Yjy%MR
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |Eu#mN
amQiH!}8R
'mv|6Y
_x-2tnIxXv
D41.$t[
我写的一个用于分页的类,用了泛型了,hoho }WR@%)7ay
~urk
Uz
java代码: ;Srzka2
e*<pO@Uy
nbw8YO(=
package com.intokr.util; rIyIZWkI
t[({KbIy
import java.util.List; 0p,_?3nX
J,h'eY5
/** 5OTZa>H
* 用于分页的类<br> pNHL &H\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #VZ-gy4$\B
* .i7"qq.M
* @version 0.01 I_c?Ky8J_|
* @author cheng Q>z(!'dw
*/ -hK^ *vJ
public class Paginator<E> { )
[)1
privateint count = 0; // 总记录数 SQ/}K8uZ
privateint p = 1; // 页编号 G{+zKs}~
privateint num = 20; // 每页的记录数 U~|)=+%O
privateList<E> results = null; // 结果 :p1_ij]ND
Oxi^&f||`
/** P=ubCS'
* 结果总数 j;_E0j#
*/ 1"l48NL L|
publicint getCount(){ b^~4 k; <
return count; p%Ns
f[1>
} So NgDFD
wG 5H^>6u>
publicvoid setCount(int count){ [MAvU?;
this.count = count; E0A[{UA
} 43`Atw`\
;P8.U(
/** YRaF@?^Gn
* 本结果所在的页码,从1开始 2 I.Q-'@
* Q9g^'a
* @return Returns the pageNo.
khP Ub,
*/ Qoz4(~I
publicint getP(){ uY&t9L8
return p; 'Urx83
} e9F+R@8
ypvz&SzIh
/**
s_!F`[
* if(p<=0) p=1 Tn'o$J
* o~x49%X<c
* @param p >b*}Td~J
*/ `b)i;m
publicvoid setP(int p){ bz\nCfU
if(p <= 0) H9=8nLb.
p = 1; Q-e(>=Gv_
this.p = p; g s%[Cv
} Mn*v&O :
:Q;mgHTNz
/** cS",Bw\
* 每页记录数量 5n=~l[O
*/ wWJM./y
publicint getNum(){ 7$kTeKiP
return num; +W|VCz
} 7MX5hZF"
:<6gP(
/** 1?y
QjW,
* if(num<1) num=1 AHplvksb
*/ E**Hu 9
publicvoid setNum(int num){ Uot LJa
if(num < 1) T\TKgO=)
num = 1; aslb^
this.num = num; ~kZ?e1H
} a^)@}4
ZGS4P 0$
/** za5E{<0
* 获得总页数 a;G>56iw
*/ 70A* !v
publicint getPageNum(){ /6'5uP
return(count - 1) / num + 1; 'Y5l3xQk
} %PM8;]
WQNFHRfO*n
/** zE=^}K+
* 获得本页的开始编号,为 (p-1)*num+1 {G-y7y+E
*/ iB*1Yy0DC
publicint getStart(){ i7O8f^|
return(p - 1) * num + 1; Mir(
}E
} nhB.>ReAi
TdrRg''@
/** m>^#:JK
* @return Returns the results. BK foeN)%
*/ VBg
M7d
publicList<E> getResults(){ r4pR[G._
return results; Nf9$q| %!
} %xwtG:IKEV
zRA,Yi4;+
public void setResults(List<E> results){ ugQySg>
this.results = results; GOY!()F
} z#srgyLt
%xN91j["
public String toString(){ ! ?GW<Rh
StringBuilder buff = new StringBuilder LE+#%>z>
A~wVY
(); *qw//W
buff.append("{"); bP1]:^ x@W
buff.append("count:").append(count); e8hwXz
buff.append(",p:").append(p); I*=
=I4qx
buff.append(",nump:").append(num); hODq&9!
buff.append(",results:").append F t;[>o
9y;8JO
(results); 6z1>(Za7>
buff.append("}"); QzD8
jk#
return buff.toString(); 'z x1kq1
} q=/ck
l\t<_p/I)^
} dQPW9~g8Hg
PLQLGb4f_;
6$\'dkufQ