Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 TKe\Bi
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {Z,_/@}N
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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 %;eD.If}
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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 [o"<DP6w
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分页支持类: ]?6Pt:N2
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java代码: 'L@kZ
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package com.javaeye.common.util; 8g0VTY4$jP
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import java.util.List; lz7?Z
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publicclass PaginationSupport { 0MI4"<
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publicfinalstaticint PAGESIZE = 30; YSh@+AN
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privateint pageSize = PAGESIZE; w7@TM%nS
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privateList items; *\(MG|S
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privateint totalCount; V1&qgAy~
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privateint[] indexes = newint[0]; hYht8?6}m
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privateint startIndex = 0; 8c\\-{
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public PaginationSupport(List items, int \$4 [qG=
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totalCount){ z"97AXu
setPageSize(PAGESIZE); n_4 r'w
setTotalCount(totalCount); 7 x'2
setItems(items); uOO\!Hqq
setStartIndex(0); ysj5/wtO0
} apOa E7|
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public PaginationSupport(List items, int %s! |,Cu
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totalCount, int startIndex){ s IFE:/1,
setPageSize(PAGESIZE); g<N;31:c\
setTotalCount(totalCount); ^)(-7H
setItems(items); b'W.l1]<-
setStartIndex(startIndex);
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{
} Vu,e]@
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public PaginationSupport(List items, int E<jW;trt_
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totalCount, int pageSize, int startIndex){ _U_O0@xi
setPageSize(pageSize); g/FZ?Wo
setTotalCount(totalCount); kH5D%`Kw
setItems(items); ?<`oKBn
setStartIndex(startIndex); :h(`eC
} )q66^%;S
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publicList getItems(){ s+?2oPa
return items; 6w=`0r3hy
}
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publicvoid setItems(List items){ W=#AfPi$&
this.items = items; }T0O~c{$i
} PY;tu#W!%
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publicint getPageSize(){ 9Ta0Li
return pageSize; Sbl = U
} n)~*BpL3
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publicvoid setPageSize(int pageSize){ ?ac4GA(
this.pageSize = pageSize; Vr|e(e.%
} u&w})`+u5
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publicint getTotalCount(){ pI:,Lt1B
return totalCount; [~u!*W
} f4
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publicvoid setTotalCount(int totalCount){ (6.uNLr
if(totalCount > 0){ ^?$,sS
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this.totalCount = totalCount; _1NK9dp:
int count = totalCount / 'zM=[#!B
[}YUi>NGA
pageSize; Q6W![571;
if(totalCount % pageSize > 0) -OSj<m<
count++; ^DN:.qQ
indexes = newint[count]; 8L,=E ap
for(int i = 0; i < count; i++){ FieDESsX>
indexes = pageSize * FpiTQC7d
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i; hJ$9Hb
} <sw@P":F
}else{ "(3u)o9
this.totalCount = 0; 0'Si
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} \XPGA uEo
} <^\rv42'(2
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publicint[] getIndexes(){ Z4EmRa30 p
return indexes; veHe
} p]%di8&;N
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publicvoid setIndexes(int[] indexes){ [lg!*
this.indexes = indexes; vjq2(I)u
} 'Y /0:)
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publicint getStartIndex(){ Z(7kwhP[`
return startIndex; g_1#if&
} fO$){(]^
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publicvoid setStartIndex(int startIndex){ v,S5C
if(totalCount <= 0) 4WJY+)
this.startIndex = 0; p_h/hTi
elseif(startIndex >= totalCount) QYMfxpiC
this.startIndex = indexes yo=L1;H
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[indexes.length - 1]; ZRG
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elseif(startIndex < 0) >Jmla~A
this.startIndex = 0; c3 O/#*
else{ F?|Efpzow?
this.startIndex = indexes *m}8L%<HT
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[startIndex / pageSize]; =w!ik9
} \c
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} HiA E9
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publicint getNextIndex(){ }! EVf
int nextIndex = getStartIndex() + dgjK\pH`h
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pageSize; ;NR|Hi]
if(nextIndex >= totalCount) Z^:_,aJ?
return getStartIndex(); g#=<;X2
else >I|8yqbfm
return nextIndex; st;iGg
} b2OwLt9
b)<WC$"
publicint getPreviousIndex(){ SHX`/
int previousIndex = getStartIndex() - ~= *o
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pageSize; z.Ic?Wz7
if(previousIndex < 0) bGCC?}\
return0; ==OUd6e}
else /)6T>/
return previousIndex; &t[[4+Qt
} -67Z!N
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} (N}-]%#
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抽象业务类 y#j7vO
java代码: 4<i#TCGex3
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/** 5rows]EJJl
* Created on 2005-7-12 { c#US
*/ w'K7$F51
package com.javaeye.common.business; CefFUqo4
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import java.io.Serializable; +@Qr GY
import java.util.List; gx.\H3y
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import org.hibernate.Criteria; ENZym
import org.hibernate.HibernateException; c!ZZMCs
import org.hibernate.Session; k( :Bl
import org.hibernate.criterion.DetachedCriteria; 6G2~'zqPc~
import org.hibernate.criterion.Projections; <D/K[mz-
import /_0B5,6R
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org.springframework.orm.hibernate3.HibernateCallback; R iLl\S#
import '#7k9\
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org.springframework.orm.hibernate3.support.HibernateDaoS ^%$IdDx
9;+&}:IVS
upport; h$&Tg_/'#D
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import com.javaeye.common.util.PaginationSupport; @Chl>s
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public abstract class AbstractManager extends ]lwf6'
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HibernateDaoSupport { zR<{z
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privateboolean cacheQueries = false; I?'*vAW<
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privateString queryCacheRegion; #yochxF_
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publicvoid setCacheQueries(boolean \}$|Uo$O
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cacheQueries){ ^3dc#5]Xf
this.cacheQueries = cacheQueries; I{89chi
} q`1tUd 4G
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publicvoid setQueryCacheRegion(String ,Vi_~b
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queryCacheRegion){ ]`$6=)_X
this.queryCacheRegion = IU8zidn&
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queryCacheRegion; $5i\D
rs
} ~^2w)-N
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publicvoid save(finalObject entity){ oJTEN}fL
getHibernateTemplate().save(entity); Ak?9a_f
} uOv<*Jld*
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publicvoid persist(finalObject entity){ PEI$1,z
getHibernateTemplate().save(entity); {N2GRF~c-y
} 8xLQ"
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publicvoid update(finalObject entity){ ww{k_'RRJ
getHibernateTemplate().update(entity); FEk9a^Xyx
} Xex7Lr&
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publicvoid delete(finalObject entity){ g$uiwqNA%
getHibernateTemplate().delete(entity); wO,qFY
} +S~ u ,=
{ 4j<X5V
publicObject load(finalClass entity, :zU4K=kR
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finalSerializable id){ k9
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return getHibernateTemplate().load c +]r
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(entity, id); ~T@E")uR
} E<yQB39
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publicObject get(finalClass entity, wrkw,H
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finalSerializable id){ u0wu\
return getHibernateTemplate().get 96\FJHtZ
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(entity, id); ;l;jTb ^l
} "Erphn
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publicList findAll(finalClass entity){ )j8'6tk)Z
return getHibernateTemplate().find("from oc"p5Y3,Os
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" + entity.getName()); tV=Qt[|@
} ?*~
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publicList findByNamedQuery(finalString $(62j0mS>
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namedQuery){ <2(X?,N5BD
return getHibernateTemplate (hwzA
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().findByNamedQuery(namedQuery); <IZr..|O
} t 9(,JC0
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publicList findByNamedQuery(finalString query, D!* SA
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finalObject parameter){ gkK(7=r%
return getHibernateTemplate :tV"uWZFU
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().findByNamedQuery(query, parameter); 2_Lu0Yrg
} Lj /^cx
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publicList findByNamedQuery(finalString query, n!zB+hW
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finalObject[] parameters){ N n_b
return getHibernateTemplate t]sk[
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().findByNamedQuery(query, parameters); !v3d:n\W8
} |$tF{\
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publicList find(finalString query){ p_xJKQS
return getHibernateTemplate().find %5L~&W}^"
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(query); fbI5!i#lz
} iw.F8[})
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publicList find(finalString query, finalObject <e Y2}Ml
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parameter){ h/5V~ :)
return getHibernateTemplate().find T pCXe\W
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(query, parameter); <DMm
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} ]Y,V)41gCE
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public PaginationSupport findPageByCriteria +^J&x>5
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(final DetachedCriteria detachedCriteria){ zq5N@dF
return findPageByCriteria 6oWFj eZ0
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); cm!vuoB~~
} iJZvVs',
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public PaginationSupport findPageByCriteria di;~$rI!?
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(final DetachedCriteria detachedCriteria, finalint % M_F/ O
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startIndex){ pvWNiW:~k
return findPageByCriteria PY CG#U
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(detachedCriteria, PaginationSupport.PAGESIZE, )1R[~]y
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startIndex); P/S ,dhs(
} de8xl
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public PaginationSupport findPageByCriteria S!-t{Q+j^
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(final DetachedCriteria detachedCriteria, finalint *"jlsI
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pageSize, r{*Qsaw
finalint startIndex){ bz1`f >%l
return(PaginationSupport) 'Q*.[aJt
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getHibernateTemplate().execute(new HibernateCallback(){ "Z';nmv'N
publicObject doInHibernate L{ej<0 yr
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(Session session)throws HibernateException { >z3l@
Criteria criteria = nr>Yj?la
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detachedCriteria.getExecutableCriteria(session); ZXj*Vu$_4
int totalCount = h5vetci/
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((Integer) criteria.setProjection(Projections.rowCount MO1H?Uhx
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()).uniqueResult()).intValue(); [IyC}lSW^-
criteria.setProjection eiA$) rzy
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(null); M )v='O<H8
List items = Z@ec}`UO|u
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criteria.setFirstResult(startIndex).setMaxResults un`4q-S7
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(pageSize).list(); Dl?:Mh
PaginationSupport ps = #T>pu/EQX_
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new PaginationSupport(items, totalCount, pageSize, Tv,ZS
3#uc+$[
startIndex);
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return ps; y2B'0l
} s=R^2;^
}, true); &?j\=%
} M?m@o1\;W
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public List findAllByCriteria(final t ,EMyZ
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DetachedCriteria detachedCriteria){ D;:p6q}hT
return(List) getHibernateTemplate l?X)]1
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().execute(new HibernateCallback(){ "?_af
publicObject doInHibernate Q{
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(Session session)throws HibernateException { fG@]G9Z
Criteria criteria = ]P_yN:~
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detachedCriteria.getExecutableCriteria(session); bdBLfWe
return criteria.list(); ;e2D}
} I,/E.cRV<
}, true); y
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} i"^ yy+
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public int getCountByCriteria(final R_80J=%0
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DetachedCriteria detachedCriteria){ Tkj
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Integer count = (Integer) /mn'9=ks
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getHibernateTemplate().execute(new HibernateCallback(){ Q0XSQ Ol
publicObject doInHibernate xd`\Ai
x45F-w{
(Session session)throws HibernateException { wF-H{C'
Criteria criteria = H:q;IYE+a
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detachedCriteria.getExecutableCriteria(session); a3[,3
return Eh *u6K)Z
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criteria.setProjection(Projections.rowCount ?%T]V+40
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/D
()).uniqueResult(); j^/^PUR
} z>*\nomOn=
}, true); TQpR'
return count.intValue(); EQy~ ^7V B
} c&g*nDuDj
} 0.~s>xXp
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用户在web层构造查询条件detachedCriteria,和可选的 V|2[>\Cv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ^_=bssaOd
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PaginationSupport的实例ps。 8wCB}q C
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ps.getItems()得到已分页好的结果集 Rz<'&Z>;
ps.getIndexes()得到分页索引的数组 "!#KQ''R
ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 q^}iXE~
ps.getNextIndex()下一页索引 G,b*Qn5#
ps.getPreviousIndex()上一页索引 Ki[&DvW:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,/eAns`ZU
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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 Cv<
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一下代码重构了。 M?qvI
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我把原本我的做法也提供出来供大家讨论吧: Y";KWA}b
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首先,为了实现分页查询,我封装了一个Page类: r:t3Kf`+E-
java代码: > q8)~
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/*Created on 2005-4-14*/ 'Z6x\p
package org.flyware.util.page; gAK"ShOhG=
G9~ 4?v6:
/** /!pJ" @
* @author Joa
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* N}'2GBqfU4
*/ I$ ?.9&.&
publicclass Page { =<r1sqf
XJA];9^
/** imply if the page has previous page */ Z1U@xQj
privateboolean hasPrePage; I(qFIV+HR
"8\2w]"
/** imply if the page has next page */ Ime"}*9
privateboolean hasNextPage; PebyH"M(
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/** the number of every page */ wu0q.]
privateint everyPage; rouaT
$nNCBC=
/** the total page number */ T:*l+<?
privateint totalPage; &[5pR60
xC 4L`\
/** the number of current page */ m(^nG_eX
privateint currentPage; 2I_~]X53[
7DWGYvv[
/** the begin index of the records by the current 8Q73h/3
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query */ ZDm Y${J
privateint beginIndex; wAc;{60s]
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/** The default constructor */ m-<m[ 49
public Page(){ r"`7ezun:
yVyh\u\
} pL,l
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/** construct the page by everyPage 1H8/b D
* @param everyPage Q6xA@"GJ
* */ [$z-
public Page(int everyPage){ )h0b}HMW)
this.everyPage = everyPage; +77B656
} b[ ~-b
/])P{"v$^
/** The whole constructor */ ]&X}C{v)G
public Page(boolean hasPrePage, boolean hasNextPage, mTL JajE/
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int everyPage, int totalPage, =G`g-E2
int currentPage, int beginIndex){ dEZlJo@J
this.hasPrePage = hasPrePage; ipS:)4QFxJ
this.hasNextPage = hasNextPage; -[[(Zx
this.everyPage = everyPage; zxeT{AFPr?
this.totalPage = totalPage; -0P9|;h5
this.currentPage = currentPage; 5 &0qr$
this.beginIndex = beginIndex; .Gb!mG
} Y;kiU
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/** ZWQ/BgKB
* @return Hz>Dp
!
* Returns the beginIndex. jW>K#vj
*/ xL"O~jTS
publicint getBeginIndex(){ t$rla_rbY
return beginIndex; k`J|]99Wb
} I8uFMP
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/** /dHIm`. Z
* @param beginIndex }
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* The beginIndex to set. <T]ey
*/ "egpc*|]
publicvoid setBeginIndex(int beginIndex){ 0B:
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this.beginIndex = beginIndex; KtHkLYOCG
} ]`M2Kwp
ygQe'S{!S\
/** pj7v{H +
* @return 1:J+`mzpl
* Returns the currentPage. IL`=r6\
*/ t8`wO+4@
publicint getCurrentPage(){ ;*0?C'h=
return currentPage; !@ {sM6U
} -F MonM
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/** <LN7+7}
* @param currentPage *D.Ajd.G
* The currentPage to set. <,\U,jU_
*/ ^9kx3Pw?8
publicvoid setCurrentPage(int currentPage){ 4eJR=h1
this.currentPage = currentPage; L$,yEMCe
} W||&Xb
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/** 8 [D"
* @return qw{`?1[+
* Returns the everyPage. x_r*<?OZ
*/ Udq!YXE0
publicint getEveryPage(){ \>X!n2rLZe
return everyPage; Sb(OG 6
} h}kJ,n
-gUp/#l1
/** %Aqf=R_^
* @param everyPage $lq.*UQ;0
* The everyPage to set. SmIcqM
*/ aemi;61T\
publicvoid setEveryPage(int everyPage){ opMnLor
this.everyPage = everyPage; /aIGq/;Y+a
}
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bkS"]q)>
/** \`E^>6!]q
* @return ?'_6M4UKa
* Returns the hasNextPage. gtePo[ZH.P
*/ _W^;a
publicboolean getHasNextPage(){ X0R EC%
return hasNextPage; e5
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} {`,)<R>}
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/** eze%RjO}
* @param hasNextPage 2=/-,kOL_
* The hasNextPage to set. zTc*1(^
*/ Qj*.Z4ue
publicvoid setHasNextPage(boolean hasNextPage){ xF@&wg
this.hasNextPage = hasNextPage; jFUpf.v2
} MpBdke$
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/** K6sXw[VC[
* @return w)`XM
* Returns the hasPrePage. @\o"zU
*/ I2Imb9k~B
publicboolean getHasPrePage(){ iaLZ|\`3a
return hasPrePage; PjH'5Y
} Wky9wr:g
-$DfnAh
/** : ^("L,AF
* @param hasPrePage M:b#">M
* The hasPrePage to set. =4l @A>
*/ )BvMFwQG
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; kguZ AO6
} +@~WKa
aU^6FI
/** b?c/J{me
* @return Returns the totalPage. U7?v4O]D[
* 0Qq<h;8xEc
*/ =*"8N-FU
publicint getTotalPage(){ ]Yw$A
return totalPage; ts9wSx~[+
} a[ayr$Hk?
Ikw@B)0}
/** "r*`*1
* @param totalPage QXN_ ?E,g/
* The totalPage to set. *BdH
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*/ y.c6r> }
publicvoid setTotalPage(int totalPage){ n:P:im?,y*
this.totalPage = totalPage; h<TZJCt
} QS5t~rb
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}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 V<J1.8H
5dI=;L>D
个PageUtil,负责对Page对象进行构造: J\Pb/9M/
java代码: @$ Zh^+x!
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/*Created on 2005-4-14*/ Y~85Z0l
package org.flyware.util.page; gS5MoW1
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import org.apache.commons.logging.Log; rR-[CT
import org.apache.commons.logging.LogFactory; O5 73AA
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/** >kK@tJn
* @author Joa eIY`RMo
(
* |HD>m'e
*/ i7XY3yhC
publicclass PageUtil { YWl#!"-
lAP k/G
privatestaticfinal Log logger = LogFactory.getLog U?le|tK
-smN}*3[
(PageUtil.class); %m\:AK[}
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/** 3ai[ r
* Use the origin page to create a new page `\62 iUN
* @param page qBX_v5pvVA
* @param totalRecords '-YiV
* @return 'E3T fM
*/ 1vj@qw3
publicstatic Page createPage(Page page, int 4d5c]%
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totalRecords){ z&amYwQcI
return createPage(page.getEveryPage(), 9 A ?{}c
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page.getCurrentPage(), totalRecords); t.28IHJ
} U
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/** W3tin3__
* the basic page utils not including exception N7_eLhPt*8
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handler DOKe.k
* @param everyPage {x_.QWe5
* @param currentPage 0N$7(.
* @param totalRecords UpG DLb f^
* @return page 5MB`yRVv
*/ /=m AVA
publicstatic Page createPage(int everyPage, int (yqe4
DJ, LQj
currentPage, int totalRecords){ i *.Y
everyPage = getEveryPage(everyPage); z_$c_J
currentPage = getCurrentPage(currentPage); g2|Myz)
int beginIndex = getBeginIndex(everyPage, <J&S[`U!
,SR7DiYg
currentPage); QPDh!A3T
int totalPage = getTotalPage(everyPage, FpRYffT 9u
n?EgC8b9
totalRecords); #XDgvX >
boolean hasNextPage = hasNextPage(currentPage, =#V^t$
&<BBPn@\
totalPage); 4@
boolean hasPrePage = hasPrePage(currentPage); (w hl1
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returnnew Page(hasPrePage, hasNextPage, ^el+ej/=
everyPage, totalPage, \N*([{X
currentPage, 9E2iZt]
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beginIndex); 3}fOb
} CLrX!JV>
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privatestaticint getEveryPage(int everyPage){ Q6qW?*Y
return everyPage == 0 ? 10 : everyPage; (4+P7Z,Nc
} E{|B&6$[}
H`CID*Ji
privatestaticint getCurrentPage(int currentPage){ V%oZT>T3
return currentPage == 0 ? 1 : currentPage; (SBhU:^h
} 90<g=B
{-\U)&6#v
privatestaticint getBeginIndex(int everyPage, int )R JEOl1
q*&R&K;q
currentPage){ ~(^P(
return(currentPage - 1) * everyPage; vV}w>Ap[
} h3CA,$HJ
SndR:{
privatestaticint getTotalPage(int everyPage, int 0kkDlWkzo
Q1,sjLO-a
totalRecords){ j<p.#jkT
int totalPage = 0; I%3[aBz4
U N9hZ>9
if(totalRecords % everyPage == 0) ljKIxSvCFp
totalPage = totalRecords / everyPage; +X=*>^G(-
else Y,}_LS$f
totalPage = totalRecords / everyPage + 1 ; Jl/w P
WoEK #,I;
return totalPage; ~#pATPW@(
} FJ;I1~??
YaC%69C'
privatestaticboolean hasPrePage(int currentPage){ FH~:&;
return currentPage == 1 ? false : true; e}UQN:1
} RuPnWx!
.Kb3VNgwvm
privatestaticboolean hasNextPage(int currentPage, HuevDy4
`L'g<VK;
int totalPage){ .{V"Gn9!
return currentPage == totalPage || totalPage == $'J3
/C7
k;l3^kTy
0 ? false : true; %j7b0pb
} vY4sU@+V
AQ~ xjU
1t
R^
} !"L.g u-'
m{/7)2.
C-&ymJC|
f<YYo
Q\$3l'W
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 %2\Hj0JQQ
<3;p>4gN
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 n Nt28n@
~non_pJ
做法如下: ^D+J
k8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 dHnCSOM<
WMB%?30
的信息,和一个结果集List: 2*:q$ c
java代码: aGD< #]
C96/
R_!.vGhkN
/*Created on 2005-6-13*/ P%3pM*.
package com.adt.bo; 8z9{H
#{cy( &cz
import java.util.List; @aIgif+v
@5>#<LV=E#
import org.flyware.util.page.Page; cLtVj2Wb
U$OZkHA[
/** 39X~<\&'
* @author Joa R;< q<i_l
*/ 2Rk}ovtD[
publicclass Result { s2<!Zb4
Zy}tZ RG
private Page page; Un6R)MVT
2JfSi2T
private List content; n7Ao.b%uk-
SMN.AJ
J
/** 9d5$cV
* The default constructor T c WCr
*/ QNNURf\[(
public Result(){ -#v~;Ci
super(); Vb0T)C
} y9:4n1fg
:`bC3Mr
/** +jLy>=u
* The constructor using fields ^b8~X [1J_
* y4^u&0}0$
* @param page G3.aw
* @param content `w@:h4f
*/ /"{d2
public Result(Page page, List content){ 7Uenr9)M
this.page = page; hG1:E:}
this.content = content; 86ao{l6l C
} @*6fEG{,q
\x<8
/** g) X3:=['
* @return Returns the content. /fI}QY1
*/ 1dH|/9
publicList getContent(){ ^? fOccfQ{
return content; 8w0~2-v.?V
} %8'8XDq^8
VBhUh~:Om
/** ai!u+L
* @return Returns the page. v3-/ [-XB:
*/ /$~1e7W
public Page getPage(){ RN$vKJk
return page; yJA~4
} +}:Z9AAMy
S$mv(C
/** `[/#,*\
* @param content <L}@p8Lq
* The content to set. hkMeUxS
*/ 8!_jZ f8
public void setContent(List content){ gQnr.
this.content = content; HbTVuf o
} OH`a3E{e
\6b~$\~B
/** u$nzpw0=H
* @param page &YhAB\Rw
* The page to set. w~3X
m{
*/ p Cz6[*kC
publicvoid setPage(Page page){ ]J7qsMw
this.page = page; =KE7NXu]-
} SuE~Wb5&
} :qzg?\(
VPMu)1={:p
&[E\2 E
u64#,mC[*
L}Z.FqJ
2. 编写业务逻辑接口,并实现它(UserManager, *$Q>Om]
iq&3S 0
UserManagerImpl) ipSMmpB
java代码: +H-=`+,
(NJ{>@&
LlTD =tJ0
/*Created on 2005-7-15*/ EGu%;[
package com.adt.service; w\buQ6pR)
(.J/Ql0Y
import net.sf.hibernate.HibernateException; MO`Y&<g~A
T.bFB+'E|
import org.flyware.util.page.Page; !:(+#
qGinlE&\
import com.adt.bo.Result; ~D52b1f
}M07-qIX{
/** d4Uw+3ikW
* @author Joa OSu&vFKz
*/ rj4@
publicinterface UserManager { <8r"QJY/
8Pn
public Result listUser(Page page)throws +B? qx
Q
is.t,&H4P]
HibernateException; =EJ&=t
I%T+H[,
} pbMANZU[
(,Y[2_Zv
-&/?&{Q0
(i&+= +"wn
"x,lL
java代码: 8ro`lX*F@2
=z1Lim-
~
#jQFyOh
/*Created on 2005-7-15*/ H%_^Gy8f
package com.adt.service.impl; 6 @f>
vs@d)$N
import java.util.List; ETDWG_H |
:V/".K-:J
import net.sf.hibernate.HibernateException; 6H#:rM
wE
.H:q4&
import org.flyware.util.page.Page; VU3RFl
import org.flyware.util.page.PageUtil; HE}0_x.
mxlh\'b
import com.adt.bo.Result; +t!]nE#
import com.adt.dao.UserDAO; zIa={tU
import com.adt.exception.ObjectNotFoundException; x'|ty[87
import com.adt.service.UserManager; }k-V(
axQ>~vWN/
/** '6N)sqTR
* @author Joa bT:u|/I
*/ >8Oa(9 n
publicclass UserManagerImpl implements UserManager { S_lGrk\j
>X~B1D,SV7
private UserDAO userDAO;
*yZ6"
yR$_ZXsd
/** G(E1c"?
* @param userDAO The userDAO to set. `YOYC
*/ !HTOE@
publicvoid setUserDAO(UserDAO userDAO){ {gD ED
this.userDAO = userDAO; `d <`>
} Q{/z>-X\x
W;u.@I&
/* (non-Javadoc) \Ec<ch[)c
* @see com.adt.service.UserManager#listUser sI,cX#h&Y
tU4#7b:Y
(org.flyware.util.page.Page) =!TUf/O-
*/ L>Y+}]~
public Result listUser(Page page)throws C[FHqo9M?H
%.bDK}
HibernateException, ObjectNotFoundException { 1RAkqw<E
int totalRecords = userDAO.getUserCount(); r8:r}Qj2w[
if(totalRecords == 0) Ca-"3aQkc
throw new ObjectNotFoundException f2gtz{r
AG(6.
("userNotExist"); f_k'@e {
page = PageUtil.createPage(page, totalRecords); `Vvi]>,cg`
List users = userDAO.getUserByPage(page); ^G4YvS(
returnnew Result(page, users); TQR5V\{&%
} CJ<nUIy'z
y|LHnNQ
} cAR
`{%b
k*1Lr\1
\M`qaFan5^
xe@e#9N$
@eYpARF
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lZk
z\
CE"/&I
询,接下来编写UserDAO的代码: X,Ql6uO
3. UserDAO 和 UserDAOImpl: D||0c"E
java代码: LOU P
Tm"H9
oidZWy
/*Created on 2005-7-15*/ Jm_)}dj3o
package com.adt.dao; '_v~+
IO)Y0J>x
import java.util.List; qda 2
ebA:Sq:w
import org.flyware.util.page.Page; dIC\U
F5?S8=i
import net.sf.hibernate.HibernateException; :8b'HhjM
#Y5k/NPg
/** oU=vl!\J
* @author Joa Y"FV#<9@7E
*/ /pMOinuO
publicinterface UserDAO extends BaseDAO { $N?8[
/k'7j*t Z
publicList getUserByName(String name)throws )+
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H(y`[B,}*
HibernateException; .IW`?9O$E
J[}H^FR
publicint getUserCount()throws HibernateException; < $zJi V
'lIs`Zc5N
publicList getUserByPage(Page page)throws ysnW3q!@
'/O:@P5qY
HibernateException; MCN>3/81
217G[YE-
} =j>xu|q
x80IS:TP
<Km9Mq
4 OPY
*'((_NZ>
java代码: '#6eUb
ox-m)z `7
P~ObxY|
/*Created on 2005-7-15*/ aUw-P{zp%
package com.adt.dao.impl; O3 sV)
(?e%w}
import java.util.List; Ph3;;,v '
53t_#Yte
import org.flyware.util.page.Page; Dg&6@c|
x^1udK^re
import net.sf.hibernate.HibernateException; MblRdj6
import net.sf.hibernate.Query; a_Y<daRO
x2!R&q8U>
import com.adt.dao.UserDAO; >oW]3)$4S
U9oUY> 9
/**
{/QVs?d
* @author Joa
Lt*P&
*/ G9:XEEN
public class UserDAOImpl extends BaseDAOHibernateImpl =WTSaC
XIwJhsYZ'9
implements UserDAO { !q\8`ss
d:)#-x*h7
/* (non-Javadoc) fJS:46
* @see com.adt.dao.UserDAO#getUserByName kcfT|@:MK"
bYsX?0T!p
(java.lang.String) Y4k2=w:D
*/ T;6M UmyC
publicList getUserByName(String name)throws ?.e,NHf
t/;2rIx>
HibernateException { v@qP &4Sp
String querySentence = "FROM user in class XPd mz !,b
kqBZsfF
com.adt.po.User WHERE user.name=:name"; U3_${
Query query = getSession().createQuery xF8r+{_J)
&M13F>!
(querySentence); V\`Z|'WIQD
query.setParameter("name", name); W,4!"*+
return query.list(); >9H^r\
} <Kt_
oxK,
</ [.1&S+\
/* (non-Javadoc) S= 4o@3%$
* @see com.adt.dao.UserDAO#getUserCount() G*9(O:
*/ 2+9VDf2
publicint getUserCount()throws HibernateException { jR%*,IeB
int count = 0; gG?@_ie
String querySentence = "SELECT count(*) FROM 7P1Pk?pxy
PYCN3s#Gi
user in class com.adt.po.User"; sh
:$J[
Query query = getSession().createQuery M=iTwK
@j|E"VYY
(querySentence); c_>Gl8J
count = ((Integer)query.iterate().next U}w'/:H
.\
Ijq!
()).intValue(); `*s:[k5k
return count;
\0)jWCK
} vhBW1/w&F
G^.N$wcv
/* (non-Javadoc) DhE-g<
* @see com.adt.dao.UserDAO#getUserByPage b1C)@gl !Z
[lzd'
(org.flyware.util.page.Page) jrp>Y:
*/ t]HY@@0g
publicList getUserByPage(Page page)throws gH//@`6
T]tP!a;K
HibernateException { +p%3pnj:K
String querySentence = "FROM user in class ^L%_kL_7
t\,Y<9{w
com.adt.po.User"; n{gEIUo#
Query query = getSession().createQuery c{=;lT
-`faXFW'
(querySentence); 9L>?N:%5
query.setFirstResult(page.getBeginIndex()) mi=mwN%UB
.setMaxResults(page.getEveryPage()); NzT
&K7v
return query.list(); `G$>T#Dq
} BA h'H&;V
EJn]C=_(
} >eTbg"\
P<vl+&*
>+{WiZ`
qPPe)IM'Sc
=mYf]
PIX
至此,一个完整的分页程序完成。前台的只需要调用 q;68tEupR
B<d=;V
userManager.listUser(page)即可得到一个Page对象和结果集对象 LhL |ETrJ
72, m c
的综合体,而传入的参数page对象则可以由前台传入,如果用 _V"0g=&Hc
<&\ng^Z$
webwork,甚至可以直接在配置文件中指定。 JK2{9#*
c,@Vz
7c
下面给出一个webwork调用示例: ]^ R':YE
java代码: uU^DYgs
9'*7 (j;
>M#@vIo?<6
/*Created on 2005-6-17*/ iM!2m$'s
package com.adt.action.user; JvO1tA]ij
:SaZhY
import java.util.List; ):K%
5Cdn
j
import org.apache.commons.logging.Log; ]o'o
v
import org.apache.commons.logging.LogFactory; &GLDoLk6[
import org.flyware.util.page.Page; k-ZO/yPo
,-6Oma
-
import com.adt.bo.Result; :|bL2T@>[
import com.adt.service.UserService; %r|sb=(yT
import com.opensymphony.xwork.Action; YYT;a$GTo
PaKa bPY
/** i%o%bib#
* @author Joa rn-bfzoDS
*/ Z:{|
?4
publicclass ListUser implementsAction{ p4P=T@:
X,49(-~\
privatestaticfinal Log logger = LogFactory.getLog 5|rBb[
9G[
DuYJI
(ListUser.class); h~#iGs
#&.Znk:@.f
private UserService userService; Ll
KO(Q{"
4
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private Page page; 5{HF'1XgZ*
JRB6T _U
privateList users; ]$g07 7o
@ZISv'F
/* )+L|<6J XA
* (non-Javadoc) Gsh9D
* obvE m[x!Z
* @see com.opensymphony.xwork.Action#execute() +<Gp >c
*/ MnD}i&k[
publicString execute()throwsException{ <{W{
Y\_A>
Result result = userService.listUser(page); cq[9#@
4=
page = result.getPage(); %UI^+:C
users = result.getContent(); $q\"d?n
return SUCCESS; JL,Y9G*]s
} b|_e):V|
M+:5gMB'
/** [3X\"x5@V
* @return Returns the page. }F]Z1('
*/ at?I @By
public Page getPage(){ I7_lKr3
return page; HVa D
} IT NFmD
{]6-,/3UR
/** 'ayb`
* @return Returns the users. i@9
qp?eb
*/ 45 ^ Z5t
publicList getUsers(){ &-*l{"7p+%
return users; ]0>
} 8)S)!2_h
y^H5iB[SPL
/** ;?{^LiD+F
* @param page +2{ f>KZ
* The page to set. rfonM~3?'
*/ - ;gQy[U
publicvoid setPage(Page page){ '=;e#
C`<{
this.page = page; F`4W5~`
} W_@ b. 1
@A6iY
/** s={>{,E
* @param users KH,f'`
* The users to set. #;8)UNc)}
*/ _jX,1+M
publicvoid setUsers(List users){ `LoRudf_`
this.users = users; K{d3)lVYCS
} 9<3( QR
Tbm
~@k(C
/** Osz=OO{
* @param userService #[bosb!R
* The userService to set. A_TaXl(
*/ -G>J
publicvoid setUserService(UserService userService){ oO;L l?~
this.userService = userService; yhgGvyD
} uQ3sRJi
} mo<*h&;&
2:|vJ<Q
|]<#![!h#
b#@xg L*D
~ox}e(xy
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, g#i~^4-1
3chx4
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 WzFXF{(
A!GvfmzqIn
么只需要: vk|f"I
java代码: B{\Y~>]Pj
l1]N&jN{
(LsVd2AbR
<?xml version="1.0"?> d_(>:|oh
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork z$1|D{
Vl+UC1M}B>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- EPW4
h/I
hRXnig{;3
1.0.dtd"> +FNGRL
;uAh)|;S#
<xwork> >e;jGk?-
/
xv5we~
<package name="user" extends="webwork- 1
K}gX>F
~Q=;L>Qd
interceptors"> 97 SS0J
oC"
[rn
<!-- The default interceptor stack name {$EX :ID
s2L]H
--> Y
22Ai
<default-interceptor-ref pF6u3]
o;wSG81
name="myDefaultWebStack"/> o.r D
l'm|**
<action name="listUser" Otu?J_ d3
|};d:LwX
class="com.adt.action.user.ListUser"> #qVvh3#g
<param w &YUb,{Y
?J6Ek*E#
name="page.everyPage">10</param> .}F
39TS2
<result ]N}/L
lq
P4)Q5r
name="success">/user/user_list.jsp</result> gm5%X'XL
</action> KRGj6g+
E[t[R<v,P!
</package> .feB
VRg
;m]
n l_vg
</xwork> ?IeBo8
t$qIJt$
8r>\scS
jhz*Y}MX
)j'Qi^;(D
)}$rgYKJ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 N1Xg-u?ul#
i9 CQ~
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 v9J1Hha#
w!*ZS~v/r
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 gHh(QRA
"E7<S5cr
>lmqPuf
kt`ln
tWl')^
我写的一个用于分页的类,用了泛型了,hoho P_jav0j7g
\="U|LzG
java代码: :BR_%$
O6e$v I@
"&XhMw4
package com.intokr.util; Gfx!.[Y
\$Ky AWrZi
import java.util.List; #5y+gdN
8=bn
TJf
/** ^W}|1.uZ
* 用于分页的类<br> #/I+[|=[O
* 可以用于传递查询的结果也可以用于传送查询的参数<br> f.` 8vaV
* q9x@Pc29d
* @version 0.01 yU(}1ZID
* @author cheng N
(\n$bpTt
*/ B}NJs,'FJ
public class Paginator<E> { ga KZ4#
privateint count = 0; // 总记录数 k"7ZA>5jk
privateint p = 1; // 页编号 2ia&c@P-
privateint num = 20; // 每页的记录数 Q2oo\
privateList<E> results = null; // 结果 8MW-JZ
`Gxb98h/r
/** BbFLT@W4
* 结果总数 QDJ#zMxFD
*/ x_8sV?F
publicint getCount(){ \aof
return count; 6qQ_I0f
} s`Z.H5V>\
G$_)X%Vb I
publicvoid setCount(int count){ {8":cn
j
this.count = count; .mwW`D
} ekfa"X_
^Rl?)_)1HE
/** D:K"J><@
* 本结果所在的页码,从1开始 $EIKi'!8
* 5mVO9Qj
* @return Returns the pageNo. YG?4DF
*/ M-;MwLx
publicint getP(){ [+5g 9tBJ
return p; lO9Ixhf~iu
} 3bd`q
$
w&}<b%l
/** 4TQmEM,
* if(p<=0) p=1 Dg~m}La
* DdISJWc'`5
* @param p TqS s*as5
*/ xIc||o$
publicvoid setP(int p){ cJ?,\@uuP
if(p <= 0) F W2x
p = 1; (!m6>m2
this.p = p; :SwA) (1
} H#X*OJ
v:!TqfI
/** !:xE
X~
* 每页记录数量 ":sp0(`h
*/ ~c+=$SL-=
publicint getNum(){ z<P?p
return num; OP= oSfa
} T6?03cSE
#CJET
/** [T'[7Z
* if(num<1) num=1 c#?~1@=
*/ 1H%p|'FKA
publicvoid setNum(int num){ 1bz^$2/k
if(num < 1) qfAnMBM1@
num = 1; O,+9r_Gh
this.num = num; o3GZcH?
} }"RVUYU
4a!%eBhX"K
/** SH"<f_
* 获得总页数 um<$L
*/ (-;(wCEE
publicint getPageNum(){ L>Ze*dt
return(count - 1) / num + 1; "`S?q G
} ',|OoxhbK
jL)Y'
/** XdzC/{G
* 获得本页的开始编号,为 (p-1)*num+1 ;X+.Ag
*/ V\n!?1{kdF
publicint getStart(){ uARkf'
return(p - 1) * num + 1; N*PJ m6-
} 3,!IV"_
247vU1
/** `6YN/"unfp
* @return Returns the results. ]m&Ss
*/ %PPy0RZ^
publicList<E> getResults(){ ncVt(!c,e
return results; ,'<NyA><
} U0|bKU
,T^A?t
public void setResults(List<E> results){ DqI "B
this.results = results; "9X(.v0ze
} Jv%)UR.]
[EVyCIcY,h
public String toString(){
C>-}BeY!
StringBuilder buff = new StringBuilder S,,Wb&A$
iB~dO @
(); ^%6f%]_
buff.append("{"); QYj 4D
buff.append("count:").append(count); sVnq|[ /
buff.append(",p:").append(p); W<O/LHKHdn
buff.append(",nump:").append(num); !K= $Q Uq
buff.append(",results:").append p vWj)4e
t"~X6o|R
(results); ;Hp78!#,
buff.append("}"); )-iUUak
return buff.toString(); 5,O:"3>c
} ZOppec1D
9qzHy}A
} 3qV~C{S
"WPWMQ+
YOfYa