Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [mwfgh&4%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~<$8i}7
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 QvqBT
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ZWr\v!4
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分页支持类: xE9s=}
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java代码: v` B_xEl
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package com.javaeye.common.util; w
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import java.util.List; B8P%4@T
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publicclass PaginationSupport { 7IvCMb&%R
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publicfinalstaticint PAGESIZE = 30; ;ndg,05_
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privateint pageSize = PAGESIZE; fZGKVxo"
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privateList items; 3$RII-}>
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privateint totalCount; cJty4m-
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privateint[] indexes = newint[0]; 6)?TWr'K e
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privateint startIndex = 0; +wio:==
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public PaginationSupport(List items, int yn=1b:kid
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totalCount){ 0xjV*0?s
setPageSize(PAGESIZE); qItI):9U
setTotalCount(totalCount); @hv9=v+
setItems(items); qVY\5`f@
setStartIndex(0); [6D>2b}:{[
} q`\lvdl
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public PaginationSupport(List items, int N1SR nJu<f
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totalCount, int startIndex){ :3G9YjzC}
setPageSize(PAGESIZE); $)uQ%/DH>
setTotalCount(totalCount); 4@VX%5uy
setItems(items); &v`kyc
setStartIndex(startIndex); }\irr9,
} Psv-y
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public PaginationSupport(List items, int "q%)we
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totalCount, int pageSize, int startIndex){ s}A]lY
setPageSize(pageSize); TX
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setTotalCount(totalCount); "C.$qk]
setItems(items); 'z\F-Ttq
setStartIndex(startIndex); B
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} Ylf 6-FbF
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publicList getItems(){ jXdn4m/O
return items; 712i|
} $~2Ao[
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publicvoid setItems(List items){ I/(`<s p
this.items = items; =];FojC6I
} n[clYi@e
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publicint getPageSize(){ 4x3`dvfp/
return pageSize; MRa>@Jn??A
} a(
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publicvoid setPageSize(int pageSize){ 4bKZ@r%
this.pageSize = pageSize; VP"L_Um
} \GkcK$Y
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publicint getTotalCount(){ m:H )b{
return totalCount; `j2z=5
} $L&*0$[]Q
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publicvoid setTotalCount(int totalCount){ 8=?I/9Xh
if(totalCount > 0){ WT0U)x( m5
this.totalCount = totalCount; @tP,l$O&
int count = totalCount / Rw7Q[I5z%
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pageSize; <;Xj4
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if(totalCount % pageSize > 0) "'8$hV65.p
count++; 1wq6E
indexes = newint[count]; d9^h
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for(int i = 0; i < count; i++){
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indexes = pageSize * 5H5<ft,
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i; ]02V,'x
} 0 8U:{LL
}else{ \;sUJr"$
this.totalCount = 0; @U9ov >E
} ?iq:Gf
} V^Nc0r
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publicint[] getIndexes(){ `yf#(YP
return indexes; 7[K$os5al
} >y az
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publicvoid setIndexes(int[] indexes){ .IgCC_C9
this.indexes = indexes; 1ptP ey
} UrtN3icph
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publicint getStartIndex(){ oZIoY*7IrQ
return startIndex; ^v`|0z\
} HID;~Ne
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publicvoid setStartIndex(int startIndex){ T+gqu
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if(totalCount <= 0) tn}9(Oa)
this.startIndex = 0; BO1Mz=q
elseif(startIndex >= totalCount) R[9[lQ'vR
this.startIndex = indexes PB`94W
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[indexes.length - 1]; }?H |9OS
elseif(startIndex < 0) No h*1u*
this.startIndex = 0; fghJj@ES
else{ `?La
this.startIndex = indexes 'Yj/M
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[startIndex / pageSize]; m. XLpD
} 7H=/FT?e]
} uu'~[SZlL
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publicint getNextIndex(){ }PoB`H'K5
int nextIndex = getStartIndex() + "zYlddh
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;
pageSize; oo<,hOv
if(nextIndex >= totalCount) _57i[U r
return getStartIndex(); ?a(ApD\
else uN'e~X6
return nextIndex; g_-Y-.M
} l].dOso$`
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publicint getPreviousIndex(){ /SjA;c!.
int previousIndex = getStartIndex() - 0<fN<iR`
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pageSize; ^
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if(previousIndex < 0) s:6H^DQ"C
return0; 8I`>tY
else ss.wX~I
return previousIndex; /wKL"M-%
} fyh9U_M);w
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} }c^`!9
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抽象业务类 P @G2F:}
java代码: r 1n l!
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/** IyOb0WiEj
* Created on 2005-7-12 o^}K]ML!t
*/ 3* 1cCM42
package com.javaeye.common.business; 9aHV~5
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import java.io.Serializable; GU([A@;
import java.util.List; **N{XxdN
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import org.hibernate.Criteria; Q9Sh2qF^2
import org.hibernate.HibernateException; Ixk L]
import org.hibernate.Session; I r]#u]Ap
import org.hibernate.criterion.DetachedCriteria; \QGh@AQp"
import org.hibernate.criterion.Projections; jb|al[p\
import \!x~FVA
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org.springframework.orm.hibernate3.HibernateCallback; #rD0`[pz
import HRn
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org.springframework.orm.hibernate3.support.HibernateDaoS m<}>'DT
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upport; 1DLAfsLlj
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import com.javaeye.common.util.PaginationSupport; >pdWR1ox
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public abstract class AbstractManager extends Y7vUdCj
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HibernateDaoSupport { 69N/_V
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privateboolean cacheQueries = false; <hkSbJF
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privateString queryCacheRegion; /Z^"[Ke
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publicvoid setCacheQueries(boolean QP>tu1B|
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cacheQueries){ }$%j} F{
this.cacheQueries = cacheQueries; 8L1vtYz
} ?TWve)U
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publicvoid setQueryCacheRegion(String )SU\s+"M
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queryCacheRegion){ *yl?M<28
this.queryCacheRegion = N>
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queryCacheRegion; nwS @r
} WoV"&9y
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publicvoid save(finalObject entity){ Fc&3tw"g
getHibernateTemplate().save(entity); c!0u,6
} P K+rr.k]
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publicvoid persist(finalObject entity){ *qa.hqas
getHibernateTemplate().save(entity); Kd r7 V
} I|n?32F
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publicvoid update(finalObject entity){ \+M6R<Qw
getHibernateTemplate().update(entity); z`}z7e'>
} ^ YOCHXg
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publicvoid delete(finalObject entity){ JtvZ~s
getHibernateTemplate().delete(entity); 5bB\i79$
} |` |#-xu
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publicObject load(finalClass entity, fZ aTckbE
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finalSerializable id){ y'5`Uo?\",
return getHibernateTemplate().load '@/1e\ -y
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(entity, id); 4aP 96
} #My14u
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publicObject get(finalClass entity, ;FGS(.mjlC
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finalSerializable id){ I A%ZCdA;
return getHibernateTemplate().get -aq3Lqi
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(entity, id); R-Ys<;
} AQ&vq$
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publicList findAll(finalClass entity){ qRSoF04!R
return getHibernateTemplate().find("from a<0q%Ax
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" + entity.getName()); G|oO
} 2qdc$I&$
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publicList findByNamedQuery(finalString ,\?s=D{
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namedQuery){ CcTdLq
return getHibernateTemplate NCdDG
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().findByNamedQuery(namedQuery); ;Fo7 -kK
} H u9nJ
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publicList findByNamedQuery(finalString query, O{7rIy
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finalObject parameter){ e*}*3kw)T
return getHibernateTemplate G4U0|^(h
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().findByNamedQuery(query, parameter); ;m7~!m)
} Vm?# ~}T
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publicList findByNamedQuery(finalString query, g(auB/0s
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finalObject[] parameters){ Oq$-*N
return getHibernateTemplate 9@ 4]t6h[
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().findByNamedQuery(query, parameters); ub!lHl
} s2(7z9jR
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publicList find(finalString query){ A;5_/ 2
return getHibernateTemplate().find M@l |n
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(query); fK ~8h
} |)xWQ KzA
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publicList find(finalString query, finalObject ^62z\Y
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parameter){ Z
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return getHibernateTemplate().find {\`y)k 7
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(query, parameter); "uP*pR^
} !vSq?!y6*P
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public PaginationSupport findPageByCriteria :{^~&jgL
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(final DetachedCriteria detachedCriteria){ &^K(9"
return findPageByCriteria -+u}u=z%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;&gk)w6*
} ;w+
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public PaginationSupport findPageByCriteria Tt9cX}&&
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(final DetachedCriteria detachedCriteria, finalint u Fw1%
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startIndex){ pouXt-%2X
return findPageByCriteria `#w#!@s#@
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(detachedCriteria, PaginationSupport.PAGESIZE, ~QlF(@ue
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startIndex); $=,pQ q
} d>mT+{3
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public PaginationSupport findPageByCriteria g\q4-
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(final DetachedCriteria detachedCriteria, finalint SUIJ{!F/
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pageSize, ? %8%1d
finalint startIndex){
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return(PaginationSupport) X `EVjK
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getHibernateTemplate().execute(new HibernateCallback(){ po'b((q
publicObject doInHibernate _68vSYr
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(Session session)throws HibernateException { iLJ@oM;2
Criteria criteria = t2vm&jk
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detachedCriteria.getExecutableCriteria(session); RM,aG}6M)M
int totalCount = ]Jm\k'u[
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((Integer) criteria.setProjection(Projections.rowCount $M4Z_zle)
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()).uniqueResult()).intValue(); ,u^{zYoW
criteria.setProjection aem gGw<
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(null); ?<^8,H
List items = n{<}<SVY
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criteria.setFirstResult(startIndex).setMaxResults +ctU7
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(pageSize).list(); QEbf]U=
PaginationSupport ps = mjg@c|rTG
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new PaginationSupport(items, totalCount, pageSize, W|Sab$h
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startIndex); `JDZR:bMaT
return ps; I}o}
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} YkMFU'?[
}, true); T?f{.a)
} T%&vq6
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public List findAllByCriteria(final sRZ<c
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DetachedCriteria detachedCriteria){ axt;}8
return(List) getHibernateTemplate - E GZ
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().execute(new HibernateCallback(){
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publicObject doInHibernate #_S]\=N(
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(Session session)throws HibernateException { zI,Qc60B
Criteria criteria = %Rf9KQ
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detachedCriteria.getExecutableCriteria(session); SPdEO3
return criteria.list(); N9#xT X
} QN$s%&O
}, true); o!~XYEXvUa
} !*~QB4\2b
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public int getCountByCriteria(final GVlT+Rs7
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DetachedCriteria detachedCriteria){ 7?uDh'utt
Integer count = (Integer) )4qspy3
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getHibernateTemplate().execute(new HibernateCallback(){ CP;<B1
publicObject doInHibernate p&Qm[!
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(Session session)throws HibernateException { R\&z3<-S
Criteria criteria = 1;<Vr<.
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detachedCriteria.getExecutableCriteria(session); 5vR])T/S0
return .'H$|"(v
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criteria.setProjection(Projections.rowCount ;qUB[Kw
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()).uniqueResult(); H.>EO|p
} tw<Oy^i
}, true); T6\]*mlr
return count.intValue(); xFThs,w
} ^swj!da
} R\7r!38
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用户在web层构造查询条件detachedCriteria,和可选的 CP2wg .
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uK(]@H7~!c
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PaginationSupport的实例ps。 H{N},B
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ps.getItems()得到已分页好的结果集 MS#*3Md&y
ps.getIndexes()得到分页索引的数组 ;P ju O
ps.getTotalCount()得到总结果数 d(^HO~p
ps.getStartIndex()当前分页索引 0nD?X+ u
ps.getNextIndex()下一页索引 d(V4;8a0
ps.getPreviousIndex()上一页索引 <N~9=g3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 t@MUNW`Q
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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 rloxM~7!,)
SYsO>`/ )
一下代码重构了。 NhNd+SCZ@
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我把原本我的做法也提供出来供大家讨论吧: ZDp^k{AN9a
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首先,为了实现分页查询,我封装了一个Page类: lo6upirZX
java代码: ?#&[1.= u
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/*Created on 2005-4-14*/ `5Z'8^
package org.flyware.util.page; .XeZjoJ$z
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/** -
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* @author Joa b5]<!~Fv:`
* h/:LC 7
*/ VCnf`wZB"
publicclass Page {
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/** imply if the page has previous page */ -W@nc
QL}
privateboolean hasPrePage; V"K.s2U^
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/** imply if the page has next page */ qHyOaKMd
privateboolean hasNextPage; tQT<1Q02i
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+
/** the number of every page */ $>_`.*I/
privateint everyPage; dD39?K/
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/** the total page number */ $39TP@?:Z)
privateint totalPage; .L1[Rv3
| ~>7_:
/** the number of current page */ o2$A2L9P
privateint currentPage; A@d 2Ukv
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/** the begin index of the records by the current =Xid"$
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query */ !h}Vz
privateint beginIndex; ~Hg*vCd ?
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/** The default constructor */ r+#g
public Page(){ _^RN$4.R>
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} XJl
3\*
*'M+oi
/** construct the page by everyPage w&es N$2
* @param everyPage 0%HAa|L,,
* */ 4/3w
*
public Page(int everyPage){ 4y5Q5)j
this.everyPage = everyPage; 4~oRcO8!Y
} h?4EVOx+
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/** The whole constructor */ \YF;/KwX$
public Page(boolean hasPrePage, boolean hasNextPage, ih75C"
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int everyPage, int totalPage, l`X?C~JhJ
int currentPage, int beginIndex){ `s=Z{bw
this.hasPrePage = hasPrePage; -<T>paE9
this.hasNextPage = hasNextPage; ;8e}X6YU
this.everyPage = everyPage; ,|zwY~lt5
this.totalPage = totalPage; pxyFM@Z](
this.currentPage = currentPage; e&[~}f?
this.beginIndex = beginIndex; 7NvRZ!
} LKZ<\%
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/** A+\rGVNH'S
* @return pD~."fb
* Returns the beginIndex. !T~uxeZ/;
*/ +zo\#8*0MF
publicint getBeginIndex(){ N0K <zxR
return beginIndex; G$/Qcr6W<
} Pu BE=9,
hS%oQ)zvE
/** Lke!VS!P&
* @param beginIndex awQB0ow'$P
* The beginIndex to set. 4Uwcc):f
*/ G-vkkNj%e
publicvoid setBeginIndex(int beginIndex){ o9]!*Y!RA
this.beginIndex = beginIndex; iM8l,Os]<f
} dd6l+z
)7E7K%:b,
/** H:z<]Rc
* @return bi-z%!Z
* Returns the currentPage. LiGECqWBa'
*/ K\lu;
publicint getCurrentPage(){ Y31e1
return currentPage; o> 1+m
} Ogh,
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/** <fgf L9-
* @param currentPage J~ z00p`E
* The currentPage to set. V4,\vgGu
*/ w(y
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publicvoid setCurrentPage(int currentPage){ Je K0><
this.currentPage = currentPage; [cfXcl
} >#.du}t
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/** A- #c1KU!
* @return (~PT(B?
* Returns the everyPage. PL3oV<\4s>
*/ vsB3n$2@u
publicint getEveryPage(){ >T\^dHtz
return everyPage; eQ=6< ^KZ
} i$!K{H1{9
MBol_#H
/** M=5hp&=
* @param everyPage %w3tzE1Hq
* The everyPage to set. +\cG{n*
*/ {]7lh#M
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; 9N<TJp,q
} 2(9~G|C.
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/** T&E'MB
* @return M(Yt9}Z%Y
* Returns the hasNextPage. R\u5!M$::
*/ pE G!j ~
publicboolean getHasNextPage(){ aSfAu!j)
return hasNextPage; W)odaab7
} !qs3fe<uh"
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/** /jn0Xh
* @param hasNextPage msZ3%L
* The hasNextPage to set. . H8 6f !=
*/ %hRH80W|
publicvoid setHasNextPage(boolean hasNextPage){ &?APY9\.
this.hasNextPage = hasNextPage; ooN?x31
} 9u_D@A"aC`
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/** W;P8'_2Y
* @return )JR&
* Returns the hasPrePage. @dhnpR:L
*/ 6{[ uCxxl
publicboolean getHasPrePage(){ x\Kt}/9 7e
return hasPrePage; *XG.?%x*|
} /+?eSgM/
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/** f"G-',O<
* @param hasPrePage 4 :M}Vz-
* The hasPrePage to set. %07vH&<C.
*/ bxAHzOB(\
publicvoid setHasPrePage(boolean hasPrePage){ F%:o6mT
this.hasPrePage = hasPrePage;
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} Y]"lcr}
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/** h&EF)~G
* @return Returns the totalPage. o?wEX%
* 7k#0EhN 1>
*/ X[1w(d U[
publicint getTotalPage(){ E*#5OT
return totalPage; ,egbU(:l
} P,K^oz}
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/** `s_k+ g
* @param totalPage ZtOv'nTD
* The totalPage to set. cIXqnb
*/ D4U<Rn6N_5
publicvoid setTotalPage(int totalPage){ oSkvTK$&i
this.totalPage = totalPage; x Z`h8
} D#d
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} $`"$ZI6[
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dY.NQ1@"
;b0;66C8|
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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 7Q #A
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个PageUtil,负责对Page对象进行构造: #8a k=lL
java代码: JYa3xeC;
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/*Created on 2005-4-14*/ E[>A# l53
package org.flyware.util.page; QT[4\)
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import org.apache.commons.logging.Log; ]oyWJ#8
import org.apache.commons.logging.LogFactory; !w:pb7+G
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/** w)"F=33}5
* @author Joa v)LSH;<
* B8?j"AF
*/ P+Sgbtc
publicclass PageUtil { LCok4N$o
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privatestaticfinal Log logger = LogFactory.getLog QTjnXg?Ri
9K=K,6
b
(PageUtil.class); %H=^U8WB
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/** p+^K$w^Cs
* Use the origin page to create a new page :<,tGYg/!
* @param page 4 }*V=>z
* @param totalRecords G(#EW+
* @return cC TTjx{
*/ gyOAvx
publicstatic Page createPage(Page page, int '2m"ocaf
ez[$;>
totalRecords){ j`_tb
return createPage(page.getEveryPage(), 8n/[oDc]
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page.getCurrentPage(), totalRecords); =T#?:J#a
} =+"-8tz8FV
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/** /n3S E0Y
* the basic page utils not including exception q`HK4~i,
-
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handler "tmr
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* @param everyPage c)SQ@B@q
* @param currentPage 5
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* @param totalRecords "cDc~~3/@
* @return page 2o~UA\:+=
*/ {/!Yavx
publicstatic Page createPage(int everyPage, int py9`q7F
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currentPage, int totalRecords){ k(_^Lq f-
everyPage = getEveryPage(everyPage); ,UneS
currentPage = getCurrentPage(currentPage); 0B(Y{*QB
int beginIndex = getBeginIndex(everyPage, u\=yY.
*.+N?%sAP)
currentPage); slV]CXW)t
int totalPage = getTotalPage(everyPage, >%85S >e
-Vj112 fI
totalRecords); __ G=xf
boolean hasNextPage = hasNextPage(currentPage, Enqs|fkbN
&Pgk$e%>
totalPage); q(}#{OO
boolean hasPrePage = hasPrePage(currentPage); x24&mWgU
M3H^s_
returnnew Page(hasPrePage, hasNextPage, mWH;-F*%
everyPage, totalPage, =_`cY^ib+
currentPage, #
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O
@{<?[
beginIndex); r&nEM6
} (sEZNo5 n
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privatestaticint getEveryPage(int everyPage){
u{|^5%)
return everyPage == 0 ? 10 : everyPage; [ejl #'*5
} tdnd~ WSR
H2E'i\
privatestaticint getCurrentPage(int currentPage){ n;~6'fxe
return currentPage == 0 ? 1 : currentPage; PfJfa/#pA
} y(jd$GM|
49dN ~k=
privatestaticint getBeginIndex(int everyPage, int \w2X.2b.F
gdG#;T'
currentPage){ xd]7?L@h.I
return(currentPage - 1) * everyPage; N-}|!pqb
} q ?m<9`
_"- ,ia[D
privatestaticint getTotalPage(int everyPage, int H:X(><J
l# |M.V6G
totalRecords){ iI!g1
int totalPage = 0; 910N1E
fl<j]{*v
if(totalRecords % everyPage == 0) x!A5j
$k0
totalPage = totalRecords / everyPage; AI3\eH+
else D?r% Y
totalPage = totalRecords / everyPage + 1 ; :/i13FQ
g
(V_&Y
return totalPage; s7:w>,v/
} qim|=
~JohcU}d
privatestaticboolean hasPrePage(int currentPage){ BHZSc(-o
return currentPage == 1 ? false : true; yb'v*B]
} @D@'S:3
K?,`gCN}v
privatestaticboolean hasNextPage(int currentPage, RJLhR_t7n
#L xfE<^
int totalPage){ anFl:=
return currentPage == totalPage || totalPage == i|G /x
[N1[khY`
0 ? false : true; @1)C3(=A
} No(S#,vJ;
$EPDa?$*
]d,#PF
} cb9@
0^-
MpLn)
Tg6nb7@P
zK&J2P`
qN6GLx%
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。 rOXh?r
~Ec@hz]js
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 Axx{G~n! [
xwu,<M
v`
做法如下: 8!Q0:4Vb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 K<7 Db4H
RUlJP
的信息,和一个结果集List: 8^"P'XQ
java代码: `pYL/[5
>
V%3w7
Y# ?M%I%j
/*Created on 2005-6-13*/ /lN09j
package com.adt.bo; w}Xy;0c
4L[-[{2
import java.util.List; R=s^bYdoy
C'CdVDmX
import org.flyware.util.page.Page; [:-o;K\.-a
_JXb|FIp
/** 8:t1%O$
* @author Joa +0FmeM&`h_
*/ /S)&d N`
publicclass Result { |Xa|%f
Q-Rt
private Page page; %TRH,-@3h
5}_DyoV
private List content; AJ-~F>gn
8sxH)"S
/** Q5qQ%cu
* The default constructor j8#B
*/ pM7xnL4
public Result(){ oi}\;TG
super(); OgBZoTT
} 3ZU<u;
Z
)dz
/** 9{V54ue;
* The constructor using fields z hFk84
* FR@##i$
* @param page >QM$
NIf@
* @param content I@9k+JB
*/ aj*%$!SU+
public Result(Page page, List content){ !t92_y3
this.page = page; )0NE_AZ?
this.content = content; 3Q"4-pd
} Bn_@R`
u6(>?r-
/** $I-i=:}g
* @return Returns the content. :X;AmLf`2u
*/ z!6:Dt6^
publicList getContent(){ ^zr]#`@G
return content; |k^ *
} u2 xb ^vu
&Kgl\;}
/** @}cZxFQ!C
* @return Returns the page. .2
/$ !'E
*/ ?5L.]Isa5
public Page getPage(){ =K2mR}n\;
return page; m*S[oy&
} P$= Y 5
p KF>_\
/** s$ 2@ |;
* @param content *0`oFTJ
* The content to set. 'M#'BQQ5
*/ ^L1#
public void setContent(List content){ ;9R;D,Gk!
this.content = content; %CP:rAd`M.
} DEw_dOJ(
WwF4`kxT
/** OxraaN`
* @param page @*gm\sU4
* The page to set. kG7q4jFwP
*/ ;ip"V 0`
publicvoid setPage(Page page){ ^{T3lQvt
this.page = page; @{Q[M3l
} lll]FJ1
} L@|W&N;%a
I~$LIdzw
jyt#C7mj-A
{zc<:^r^
eswsxJ/!
2. 编写业务逻辑接口,并实现它(UserManager, *8uSy/l
/IS
j0"/$
UserManagerImpl) =x4:jas
java代码: !ACWv*pW
XK
(y ?Y1
:H$D-pbJ4
/*Created on 2005-7-15*/ iTt"Ik'
package com.adt.service; tZ]|3wp
IwIk;pB O
import net.sf.hibernate.HibernateException; QM1-w^
lGI5
import org.flyware.util.page.Page; NW`.RGLI<
,R1`/aRy
import com.adt.bo.Result; HN\Zrb
x7X"'1U
/** 5O
Ob(
* @author Joa zv]-(<B
*/ )*I=>v.Jq
publicinterface UserManager { P nsQ[}.
_XtLO-D
public Result listUser(Page page)throws 0KyujU?sF
qwu++9BM
HibernateException; J<Wz3}w6
L!3AiAnr
} *J!oV0#1
6y,M+{
Sq&*K9:z
Tv<iHHp
n*^g^gp
java代码: GdavCwJ
BciwS_Qx
ch<Fi%)
/*Created on 2005-7-15*/ .9Bimhc6K
package com.adt.service.impl; $V~r*#$.
Z&=K+P
import java.util.List; _=jc%@]1y
/I
import net.sf.hibernate.HibernateException; !Y-MUZ$f
Dn _D6H
import org.flyware.util.page.Page; }$V]00
X
import org.flyware.util.page.PageUtil; -[s*R%w
p2PD';"
import com.adt.bo.Result; D5)qmu
import com.adt.dao.UserDAO; ??{ (.`}R~
import com.adt.exception.ObjectNotFoundException; cD8.rRyD
import com.adt.service.UserManager; )_b#c+
)$yqJ6y5
/** #$%9XD3
* @author Joa *Xt#04_
*/ /`0*!sN*5
publicclass UserManagerImpl implements UserManager { ;C-5R U
V
bK; -X cm
private UserDAO userDAO; "OFYVK\]i
JGSeu =)
/** fyx-VXu
* @param userDAO The userDAO to set. WUAjb,eo
*/ "j3Yu4_ks
publicvoid setUserDAO(UserDAO userDAO){ bOux8OHt*
this.userDAO = userDAO; [X)+(-J
} bXc7$5(!VB
Mq42^m:qe
/* (non-Javadoc) a9"x_IVU
* @see com.adt.service.UserManager#listUser 7'j?GzaQ+
|A7Yv
(org.flyware.util.page.Page) 9M~EH?>+[
*/ 0F`@/C1y55
public Result listUser(Page page)throws :q;vZ6Xd
J @"wJEF
HibernateException, ObjectNotFoundException { SS
O$.rp
int totalRecords = userDAO.getUserCount(); P f6rr9
if(totalRecords == 0) ;e()|
throw new ObjectNotFoundException d#I'9O0&
V>@NkQ<|y
("userNotExist"); 1;SW%\M
page = PageUtil.createPage(page, totalRecords); CBs0>M/
List users = userDAO.getUserByPage(page); y .S0^
returnnew Result(page, users); [f.[C5f%"'
} t3 *2Z u
@= 6}w_
} u
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s}`ydwSg8
e<l Wel
r3hjGcpaX
:doP66["!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 g$?B!!qT
qUx!-DMY
询,接下来编写UserDAO的代码: `HgT5}
3. UserDAO 和 UserDAOImpl: <'-}6f3
java代码: B y6:
9/{+,RpC
9,82Uta
/*Created on 2005-7-15*/ 7w|W\J^7r
package com.adt.dao; XkCbdb
engql;
import java.util.List; ^;c!)0Q<Z
-}MWA>an8
import org.flyware.util.page.Page; ~ra2Xyl
|
3!a=
import net.sf.hibernate.HibernateException; y{s?]hLk
EfcoJgX
/** '>`?T}a,
* @author Joa =JOupw
*/ ^lB1- ;ng
publicinterface UserDAO extends BaseDAO { \QBODJ1
_wCp.[3?t
publicList getUserByName(String name)throws ' ,a'r.HJH
}7g\1l\
HibernateException; &rorBD 5aj
zr\I1v]?1#
publicint getUserCount()throws HibernateException; PGP9-M
]"q)X{G(+
publicList getUserByPage(Page page)throws :upi2S_e
I/Hwf
HibernateException; giyKEnP
)|XmF4R
} &tj0Z:
:7e2O!zH_
R4_4 FEo
]N:SB
Z$k4T$,[-
java代码: d@b"tb}R
UVUbxFq:
uPsn~>(4
/*Created on 2005-7-15*/ 8,a&i:C
package com.adt.dao.impl; eq<xO28z
c`#E#
import java.util.List; I$n 0aR6
}wC
pr.@
import org.flyware.util.page.Page; G+=euK2]
mSY;hJi
import net.sf.hibernate.HibernateException; a^~T-;_V
import net.sf.hibernate.Query; {e/12q
ipQJn_:2
import com.adt.dao.UserDAO; d?oupW}uu
[kt!\-
/** y{uRh>l
* @author Joa TF}<,aR
*/ (Vf&,b@U_
public class UserDAOImpl extends BaseDAOHibernateImpl !?DPI)
T@U_;v|rf
implements UserDAO { 7Z0
)k9*
)r~$N0\D
/* (non-Javadoc) (8?t0}#t
* @see com.adt.dao.UserDAO#getUserByName TKx.`Cf
m
U)=StpTT
(java.lang.String) `l9Pk\X[
*/ 1tDd4r?Y
publicList getUserByName(String name)throws e#:.JbJ:D
pD9*WKEf*
HibernateException { b*',(J94
String querySentence = "FROM user in class -m(9*b{h@
Tsxl4ZK
com.adt.po.User WHERE user.name=:name"; ` Xhj7%>
Query query = getSession().createQuery Ett%Y*D+J
beRpA;
(querySentence); _VMW-trG
query.setParameter("name", name); G!RbM.6
return query.list(); y1p^
&9 U
} 89v9BWF
I5mnV<QA^
/* (non-Javadoc) "o*(i7T=n
* @see com.adt.dao.UserDAO#getUserCount() J/>Y mi,
*/
\U(qv(T
publicint getUserCount()throws HibernateException { #~ ^#%G
int count = 0; +;c)GNQ)6:
String querySentence = "SELECT count(*) FROM v(W$\XH
|>5NH'agV
user in class com.adt.po.User"; ]OL
O~2j
Query query = getSession().createQuery
z2vrV?:
[w'Y3U\i
(querySentence); n2zJ'
count = ((Integer)query.iterate().next NTASrh
dT4?8:
()).intValue(); 4:.yE|@h[
return count; _<yGen-
} :aI[
lZ
L9M0vkgri
/* (non-Javadoc) Qh<_/X?
* @see com.adt.dao.UserDAO#getUserByPage KC9_H>
.K]n<+zW
(org.flyware.util.page.Page) z$ZG`v>0
*/ m/Ou$
publicList getUserByPage(Page page)throws m X{_B!j^
as=Z_a:0N
HibernateException { -f@~{rK.L
String querySentence = "FROM user in class 15U]/?jv8
a'u:1C^\
com.adt.po.User"; JnQ5r>!>3
Query query = getSession().createQuery \B/+.\
}K1v=k
(querySentence); 0Mpc#:a%1
query.setFirstResult(page.getBeginIndex()) F6J,:
.setMaxResults(page.getEveryPage()); Opx"'HC@G
return query.list(); &o%IKB@
} L}NckL
J:LwO
} mX66}s}#
-XBD WV
wXI6KN-
,'w9@A
cc`+rD5I-
至此,一个完整的分页程序完成。前台的只需要调用 u}Kc>/AF
p?F%a;V3
userManager.listUser(page)即可得到一个Page对象和结果集对象 KnK8\p88\
n=Qz7N(M
的综合体,而传入的参数page对象则可以由前台传入,如果用 UP]X,H~stU
3H"bivK
webwork,甚至可以直接在配置文件中指定。 FbO\ #p s
s\&qvL1D
下面给出一个webwork调用示例: Cn+'!?!d,
java代码: OwRH
:l
o^HzE;L}
<g9@iUOI
/*Created on 2005-6-17*/ T7+_/
Qh
package com.adt.action.user; 9?W!E_
f4{O~?=
import java.util.List; MoAZ!cF8
BO]}E:C9
import org.apache.commons.logging.Log; G_OLUuK?C
import org.apache.commons.logging.LogFactory; uRIa
Nwohv
import org.flyware.util.page.Page; o}QtKf)W
CjeAO 2
import com.adt.bo.Result; >Vp#
import com.adt.service.UserService; (.D|%P
import com.opensymphony.xwork.Action; +7%}SV 2)
.zDm{_'
/** lHl1Ny\?
* @author Joa W[ZW=c
*/ DX|yL!4[
publicclass ListUser implementsAction{ 8":O\^i
AE?G+:B
privatestaticfinal Log logger = LogFactory.getLog V'n4iM
#ArMX3^+w7
(ListUser.class); 7Qoy~=E
UB5X2uBv
private UserService userService; Dq$co1eT
JY6&CL`C
private Page page; 6KpG,%2L#
QVEGd"WvvO
privateList users; ik:fq&=
uIeD.I'@{5
/* ?U^h:n
* (non-Javadoc) ;Nfd
* F@C^nX9
* @see com.opensymphony.xwork.Action#execute() 8AX+s\N
*/ 85fv] )\y
publicString execute()throwsException{ aNcuT,=(?8
Result result = userService.listUser(page); =A yDVWpE
page = result.getPage(); Z#Q)a;RA
users = result.getContent(); >wPMJ>
2
return SUCCESS; >R&=mo~
} Vy+UOV&v-
(K"8kQLY
/** qYi<GI*|@
* @return Returns the page. 9gS.G2
*/ OvFWX%uY
public Page getPage(){ F~qiNV
return page; "@h 5
SF
} oJ<Wh @
;:0gN|+
/** J &<uP)<
* @return Returns the users. #c2InwZV
*/ ZJ|@^^GcL
publicList getUsers(){ Xy;!Q`h(
return users; [u=DAk?8
} m{ya%F
GNv5yWQ@
/** 4_A9o9&_Rh
* @param page Ob|[/NN
* The page to set. TLkJZ4}?Q
*/ $ZQ?E^> B
publicvoid setPage(Page page){ Rlq6I?S+
this.page = page; 9gz"r
} aD5G0d?u
zF
F=v7[j
/** A{7N#-h_
* @param users 0 CJ4]mYl
* The users to set. .W>8bg'u9
*/ {]a 6o[}u
publicvoid setUsers(List users){ i"rrM1/r
this.users = users; 0M?nXHA[
} fGv`.T _d
>VAZ^kgi
/** ? }k~>. \
* @param userService 7 %P?3
* The userService to set. x%;Q
/7&$
*/ cZ"
Ut
publicvoid setUserService(UserService userService){ Wv
this.userService = userService; zn |=Q$81
} FC= %_y
} `B`/8Cvg
x+O}R D*G
}}GBCXAf_
P80z@!
GQ-owH]
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, @UO=)PxN3
,{C(<1
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ==psPyLF@
h>Z$
n`T
么只需要: -S=Zsr\
java代码: %@!Vx
Kis\Rg
lPS A
<?xml version="1.0"?> >4d2IO1\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork J! 4l-.-
>#@1
I
1.0//EN" "http://www.opensymphony.com/xwork/xwork- lQ%]](a6
JH~v e
1.0.dtd"> 6,'!z
?d%
@1#$
<xwork> t|*PC
V*l0|,9
<package name="user" extends="webwork- 5 TD"
1Tn!.E *
interceptors"> {rWu`QT
`07u}]d8
<!-- The default interceptor stack name }6]V*Kn,
0EM`,?i .Q
--> F9e$2J)C
<default-interceptor-ref k=[!{I
{6<7M
name="myDefaultWebStack"/> tg~&kaz
6|#^4D)
<action name="listUser" 'uUp1+
~(B\X?v
class="com.adt.action.user.ListUser"> Do(7LidC5
<param [pbX_
?B %y)K
name="page.everyPage">10</param> =~Jv*c
<result pFSVSSQRV|
w\;=3C`
name="success">/user/user_list.jsp</result> .i/]1X*;r^
</action> d@"eWvnlZ
N_L&!%s
</package> b]s=Uv#)
F|V_iC+
</xwork> #hd<5+$U}l
j:|60hDz^
'oTcx Jx
m7kDxs(KO
P58U8MEG
n<CJx+U
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 /[[zAq{OA
KLqu[{y.'
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。 ;ijJ%/
;FZ\PxN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 P,iLqat
;k7` `
F4Ft~:a
D{.%Dr?
dWD,iO_"@
我写的一个用于分页的类,用了泛型了,hoho ]Nt97eD)
]-%ZN+
java代码: }#<Sq57n
B0 q![
FEaf&'G]
package com.intokr.util; [X^JV/R
y%TR2CvT
import java.util.List; 4g\a$7r
I6y&6g
/** 92Ar0j]
* 用于分页的类<br> 7@EYF
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;
tvB{s_
*
{yt]7^
* @version 0.01 N>ct`a)BD/
* @author cheng G:WMocyXI'
*/ mSwOP
public class Paginator<E> { gyCb\y+\a
privateint count = 0; // 总记录数 tx5_e[
privateint p = 1; // 页编号 CM5A-R90
privateint num = 20; // 每页的记录数 B"KsYB79t
privateList<E> results = null; // 结果 ;S?1E:\av
jcq(=7j
/** D<++6HN
* 结果总数 niy@'
*/ & p_;&P_
publicint getCount(){ i+&="Z@
return count; ^Y'J0v2
} o4~ft!>
#mkr]K8A4
publicvoid setCount(int count){ g=U?{<8.m
this.count = count; (sqS(xIY
} RTY$oUqlZ
4`8.\
/** ['R=@.
* 本结果所在的页码,从1开始 :!} zdeRJ
* hq,;H40%/
* @return Returns the pageNo. TJ;v}HSo
*/ Q.yKbO<[
publicint getP(){ ^_+ks/
return p; Tl%4L%
bE
} {eZj[*P
rXm!3E6JL
/** \~?s= LT
* if(p<=0) p=1 (B$FX<K3
* +]
5a(/m.~
* @param p _-!6@^+
*/ +z[!]^H]4
publicvoid setP(int p){ R3@iN&
if(p <= 0) c=b\9!hr_E
p = 1; @H_LPn
this.p = p; c''O+,L1+
} .86..1
4Dd9cG,lN
/** S}<
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* 每页记录数量 GecXM Aa:2
*/ >{??/fBd-
publicint getNum(){ zp9 ?Ia
return num; EV(/@kN2
} fZ376Z:S$
*ap#*}r!Nk
/** }>1E,3A:%G
* if(num<1) num=1 $U0(%lIU
*/ j?mJ1J5
publicvoid setNum(int num){ #[xNEC)
if(num < 1) $I/p 6
num = 1; jF5JpyOc
this.num = num; B~ez>/H^
} .cabw+&7
kL3=7t^ 1
/** <'B^z0I,
* 获得总页数 MmK\|CtV
*/ JQ1VCG
publicint getPageNum(){ .)GVb<w
return(count - 1) / num + 1; Wm,,OioK
} 4HHf3j!5
`^}9= Q'r
/** :ox CF0Y
* 获得本页的开始编号,为 (p-1)*num+1 @gj5'
*/ zKutx6=aj
publicint getStart(){ 19vD(KC<
return(p - 1) * num + 1; yh)q96m-V=
} fI|1@e1
#n7{ 3)
/** 7.t$#fzi
* @return Returns the results. <>Im$N ai
*/ oEN_,cUp
publicList<E> getResults(){ `otQ'e~+t
return results; r=`>'3
} x
} S=2,jPX2r
3IkG*enI
public void setResults(List<E> results){ k?#6j1pn
this.results = results; #? *jdN:
} 6p@ts`#
GND[f}
public String toString(){ 6uyf
StringBuilder buff = new StringBuilder |H4'*NP"
z|2liQrf+
(); `jHGNi
buff.append("{"); 3C2>
buff.append("count:").append(count); qrkT7f
buff.append(",p:").append(p); rUO{-R
buff.append(",nump:").append(num); ;GAYcVB
buff.append(",results:").append K0\WN"ua;
rBf?kDt6l
(results); )3AT=b
buff.append("}"); 'w2;oO
return buff.toString(); "J#:PfJ%
} UU;:x"4
D|o@(V
} 63HkN4D4
7yp*I[1Qf>
bv/b<N@4?$