Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qKC*jDW
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 7bS[\5
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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 qTF>!o#\:
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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 UV.9KcN.
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分页支持类: koZp~W-
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java代码: aM!#
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package com.javaeye.common.util; !k9h6/b6
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import java.util.List; NhX.yLb$
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publicclass PaginationSupport { EQC
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publicfinalstaticint PAGESIZE = 30; _9r{W65s
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privateint pageSize = PAGESIZE; 0 +LloB
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privateList items; IIiN1
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privateint totalCount; 4V8wB}y7e
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privateint[] indexes = newint[0]; taaAwTtk?A
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privateint startIndex = 0; ':4pH#E
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public PaginationSupport(List items, int ]5/U}Um
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totalCount){ F9r*ZyNlx
setPageSize(PAGESIZE); vy2aNUmt
setTotalCount(totalCount); ZQA
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setItems(items); 5&=n
setStartIndex(0); )W|jt/
} p>3'77
V
n4y6Ua9m{
public PaginationSupport(List items, int %;$Y|RbmqE
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totalCount, int startIndex){ HH@xnd
setPageSize(PAGESIZE); K9'*q3z
setTotalCount(totalCount); 8-YrmP2k
setItems(items); x`i`]6q
setStartIndex(startIndex); S\gP= .G
} :G/]rDtd
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public PaginationSupport(List items, int s;$TX30 4
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totalCount, int pageSize, int startIndex){ f om"8iL1
setPageSize(pageSize); =A6O}0z
setTotalCount(totalCount); %= y3
setItems(items); Q}]kw}b
setStartIndex(startIndex); ][#*h`I
}
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publicList getItems(){
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return items; LfXr(2u
} N\p]+[6
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publicvoid setItems(List items){ J5( D7rp#
this.items = items; @rE)xco
} Uy|=A7Ad
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publicint getPageSize(){
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return pageSize; @6'E8NFl
} #2ASzCe
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publicvoid setPageSize(int pageSize){ *r$.1nke
this.pageSize = pageSize; 6 <S&~q
} [;YBX]t
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publicint getTotalCount(){ ^QR'yt3e
return totalCount; ;o459L>sW
} Kg-X]yu*0
i9U_r._qj;
publicvoid setTotalCount(int totalCount){ l0xFt
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if(totalCount > 0){ Go7hDmu
this.totalCount = totalCount; K(fLqXE%
int count = totalCount / f<p4Pkv
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pageSize; L#q9_-(#
if(totalCount % pageSize > 0) Er1u1@
count++; b7sE
indexes = newint[count]; zb}+ m#q
for(int i = 0; i < count; i++){ fYM6wYJ
indexes = pageSize * (H%d]
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i; EFt`<qwj
} <`UG#6z8
}else{ C_ZD<UPA\
this.totalCount = 0; H-KwkH`L4
} _D,f4.R
} mX.3R+t
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publicint[] getIndexes(){ Mq lo:7
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return indexes; @EOR]^?!]
} M2P@ &
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publicvoid setIndexes(int[] indexes){ -<JBKPtA
this.indexes = indexes; [*{\R`M
} ^H6d;n
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publicint getStartIndex(){ VSpt&19
return startIndex; wW! r}I#
} X+E\]X2
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publicvoid setStartIndex(int startIndex){ Yj7= T%5
if(totalCount <= 0) + >gbZ-S
this.startIndex = 0; nf.:5I.
elseif(startIndex >= totalCount) @))}\:
this.startIndex = indexes qTh='~m4[
ka)LK@p6
[indexes.length - 1]; ^ lc}FN
elseif(startIndex < 0) :`u&TXsu
this.startIndex = 0; K[>@'P}y
else{ UtBlP+bE?y
this.startIndex = indexes i,Wm{+H-O
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[startIndex / pageSize]; Pn'(8bRm
} (GcKaUg8*
} ml33qXW:
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publicint getNextIndex(){ ;.Oh88|k
int nextIndex = getStartIndex() + Xtu`5p_Qv
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pageSize; bqQO E4;
if(nextIndex >= totalCount) v;bP8)mI
return getStartIndex(); %6IlE.*,
else Q^MXiEO+
return nextIndex; 1u"*09yZd
} ?%xhe
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publicint getPreviousIndex(){ W93JY0Ls9|
int previousIndex = getStartIndex() - :ONuWNY
N
NB
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pageSize; Y(
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if(previousIndex < 0) 42J';\)oP
return0; a?,[w'7FU
else \n*7#aX/
return previousIndex; 4Ay`rG
} WE.$a t{*h
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} 9o`7Kc/g
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抽象业务类 kByrhK5U
java代码: 2 ]V>J
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/** A{aw<
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* Created on 2005-7-12 (aJP: ^
*/ YA"Ti9-EV
package com.javaeye.common.business; %kK
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import java.io.Serializable; 9|N"@0<B
import java.util.List; 1tc]rC4h
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import org.hibernate.Criteria; .0
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import org.hibernate.HibernateException; b46[fa
import org.hibernate.Session; hgweNRTh!
import org.hibernate.criterion.DetachedCriteria; W,HH *!
import org.hibernate.criterion.Projections; \K?(
import cPq Dsl3
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org.springframework.orm.hibernate3.HibernateCallback; .:{h{@a
import r=~WMDCz@
11)/] ?/j
org.springframework.orm.hibernate3.support.HibernateDaoS %NT`C9][
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upport; Nm6Z|0S
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import com.javaeye.common.util.PaginationSupport; axK6sIxx
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public abstract class AbstractManager extends Uvjdx(fY[a
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HibernateDaoSupport { 'yPCZ`5H(
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privateboolean cacheQueries = false; .KLm39j(
-?< Ww{
privateString queryCacheRegion; hWD !
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publicvoid setCacheQueries(boolean TL},Unq
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cacheQueries){ ~L %Pz0Gg
this.cacheQueries = cacheQueries; M}Nb|V09
} $!YKZ0)B'0
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publicvoid setQueryCacheRegion(String 7FmbV/&c
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queryCacheRegion){ (Wd_G-da
this.queryCacheRegion = op hH9D
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queryCacheRegion; P?9nTG
} ]y3pE}R
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publicvoid save(finalObject entity){ KX?o
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getHibernateTemplate().save(entity); T-4/d5D[
} $ A-+E\vQ@
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publicvoid persist(finalObject entity){ $_Y/'IN`k
getHibernateTemplate().save(entity); -1qZqU$h
} @S`$C
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publicvoid update(finalObject entity){ *#3*;dya]
getHibernateTemplate().update(entity); P^ptsZ%
} PX;Vo~6
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publicvoid delete(finalObject entity){ `J72+ RA
getHibernateTemplate().delete(entity); 5]jx5!N
} )O,wRd>5
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publicObject load(finalClass entity, >(hSW~i~
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finalSerializable id){ 8g\wVKkTQp
return getHibernateTemplate().load
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(entity, id); t?gJNOV
} a%Uw;6|{
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publicObject get(finalClass entity, !CVuw
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finalSerializable id){ HbcOTd)=5
return getHibernateTemplate().get fJaubDxa
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(entity, id); e# t3u_
} \[:PykS
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publicList findAll(finalClass entity){ v @:~mwy
return getHibernateTemplate().find("from kr%2 w
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" + entity.getName()); XMGx^mn
} i=YXKe6fD
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publicList findByNamedQuery(finalString Ng\/)^
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namedQuery){ /D]Kkm)
return getHibernateTemplate *c{wtl@
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().findByNamedQuery(namedQuery); >ajuk
} yQ9ZhdQS
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publicList findByNamedQuery(finalString query, ^$!987"
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finalObject parameter){ #O"
return getHibernateTemplate ["}A
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().findByNamedQuery(query, parameter); +noZ<KFW
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} BPqk"HG]T
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publicList findByNamedQuery(finalString query, @:Di`B_{
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finalObject[] parameters){ ^(ScgoXva
return getHibernateTemplate ;6ky5}z
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().findByNamedQuery(query, parameters); QdQd(4/1
} +iy7e6P
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publicList find(finalString query){ $$hv`HE^l
return getHibernateTemplate().find RPVT*`o
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(query); oBA`|yW{U
} 1~J5uB 4
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publicList find(finalString query, finalObject 5!Bktgk.
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parameter){ n 6{2]&sd
return getHibernateTemplate().find MM?`voj~`p
piOXo=9H.
(query, parameter); ,w{m3;]_%
} UNDi_6Dy
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public PaginationSupport findPageByCriteria q_ %cbAcD
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(final DetachedCriteria detachedCriteria){ lv]quloT
return findPageByCriteria YD\]{,F|
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q/ZkW
} +R6a}d/K
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public PaginationSupport findPageByCriteria y:d{jG^
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(final DetachedCriteria detachedCriteria, finalint XX6 T$pA6
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startIndex){ o%[U
return findPageByCriteria Z)pz,
'9s5OTkN ;
(detachedCriteria, PaginationSupport.PAGESIZE, p_{("zQ
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startIndex); WZZ4]cC
} 1zftrX~v!X
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public PaginationSupport findPageByCriteria 5l DFp9
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(final DetachedCriteria detachedCriteria, finalint x0Yse:RE^
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pageSize, |.P/:e9
finalint startIndex){ [u
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return(PaginationSupport) }CDk9Xk
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getHibernateTemplate().execute(new HibernateCallback(){ Q7gY3flg
publicObject doInHibernate pI;NL
[
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(Session session)throws HibernateException { 6Pn8f
Criteria criteria = p'n4)I2#
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detachedCriteria.getExecutableCriteria(session); la
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int totalCount = ceT&Y{T
^j )BKD-
((Integer) criteria.setProjection(Projections.rowCount K93p"nHN
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()).uniqueResult()).intValue(); ZH ,4oF
criteria.setProjection ] asBd"
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(null); 1tMQqI`N
List items = !k&Q 5s:
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criteria.setFirstResult(startIndex).setMaxResults 7v7G[n
_:`!DIz~9}
(pageSize).list(); }fR,5|~X
PaginationSupport ps = nZy X_J,Vd
al&(-#1
new PaginationSupport(items, totalCount, pageSize, {@Y
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startIndex); _qXa=|}V.
return ps; otJ!UfpR8
} =~KsS}`1,
}, true); =Gk/k}1
} C\ZkGX
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public List findAllByCriteria(final %\$;(#h
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DetachedCriteria detachedCriteria){ }!>=|1fY
return(List) getHibernateTemplate &PWB,BXv
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().execute(new HibernateCallback(){ c`*TPqw(B[
publicObject doInHibernate ,m=4@ofX
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(Session session)throws HibernateException { *Vw\'%p*
Criteria criteria = 8qEK+yi,
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detachedCriteria.getExecutableCriteria(session); ^! 8P<y
return criteria.list(); Xjio Z
} q.4A(,
}, true); ]iNEw9
} -62'}%?A<C
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public int getCountByCriteria(final
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DetachedCriteria detachedCriteria){ u{N,Ib
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Integer count = (Integer) ;6ecrQMw&
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getHibernateTemplate().execute(new HibernateCallback(){ COzyG.R.
publicObject doInHibernate `(6r3f~XJ
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(Session session)throws HibernateException { ^YdcAHjK
Criteria criteria = Sn4[3JV $l
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detachedCriteria.getExecutableCriteria(session); ?E%ELs_Dl
return k67a'pmyJ
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criteria.setProjection(Projections.rowCount jw}}^3.
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()).uniqueResult(); 0Uk@\[1ox
} jOpcV|2
}, true); 9+s.w25R
return count.intValue(); wkqX^i7ls
} Cv
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} ?Iyo9&1&
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ps
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用户在web层构造查询条件detachedCriteria,和可选的 ##Q/I|
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h_1T,f(
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PaginationSupport的实例ps。 G0u LmW70
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ps.getItems()得到已分页好的结果集 3p2P=
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ps.getIndexes()得到分页索引的数组 mbnV[
ps.getTotalCount()得到总结果数 9Y>8=#.c
ps.getStartIndex()当前分页索引 kF;DBN
ps.getNextIndex()下一页索引 HHX-1+L
ps.getPreviousIndex()上一页索引 r:&`$8$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 J_Ltuso
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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 8]4U`\k4
6 3`{.yZ*z
一下代码重构了。 V-n&oCS+f
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我把原本我的做法也提供出来供大家讨论吧: +w@M~?>
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首先,为了实现分页查询,我封装了一个Page类: U9D!GKVp
java代码: ?(*t@
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/*Created on 2005-4-14*/ 5JEbe
package org.flyware.util.page; DvvT?K
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/** :l|%17N
* @author Joa HV6f@
* *(PL
_/:
*/ &Ysosy*
publicclass Page { |6=p{y
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/** imply if the page has previous page */ &Tl
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privateboolean hasPrePage; ^rvx!?zO
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/** imply if the page has next page */ vSi_t
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privateboolean hasNextPage; WTImRXK4
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/** the number of every page */ 6[ OzU2nB
privateint everyPage; 3~nnCR[R
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/** the total page number */ >#,G}xf
privateint totalPage; 6#IU*
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/** the number of current page */ ui (^k $
privateint currentPage; 0b4R
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/** the begin index of the records by the current /dv<qp
el:9 wq
query */ 5@^ dgq
privateint beginIndex; bdGIF'p%
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/** The default constructor */ k)TSR5A
public Page(){ Q#nOJ(KV
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}
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/** construct the page by everyPage N^B o
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* @param everyPage n_3O-X(
* */ t3dlS`O
public Page(int everyPage){ TLoz)&@
this.everyPage = everyPage; kOh{l: 2-+
} 5|jw^s7
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/** The whole constructor */ MwmUgN"g
public Page(boolean hasPrePage, boolean hasNextPage, &QhX1dT+
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SM`w;?L:?
int everyPage, int totalPage, +-E~6^>
int currentPage, int beginIndex){ 1Bpv"67
this.hasPrePage = hasPrePage; <{~6}6o
this.hasNextPage = hasNextPage; ;j4?>3
this.everyPage = everyPage; i;!H!-sM
this.totalPage = totalPage; n u'M
39{
this.currentPage = currentPage; XS$OyW_Q
this.beginIndex = beginIndex; Mi]L]-L
} 'Ysx=
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/** +[5.WC7J
* @return
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* Returns the beginIndex. da (km+
*/ C-iK$/U
publicint getBeginIndex(){ yRo-EP
return beginIndex; e^ v.)
} jg?x&'u\)
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/** n> ^[T[.S
* @param beginIndex 1UKg=A-q
* The beginIndex to set. V{<xff
*/ W"Gkq!3u{
publicvoid setBeginIndex(int beginIndex){ }g4 M2|
this.beginIndex = beginIndex; q7"7U=W0
} =2@B&
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/** a{[x4d,z
* @return 6P';DB
* Returns the currentPage. U^Xm)lL
*/ )HX|S-qRU=
publicint getCurrentPage(){ +zy=50,
return currentPage; D}vmwg@3
} gB<3-J1R
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/** `3:.??7N
* @param currentPage sqW*
pi
* The currentPage to set. 23h%
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*/ 7U"[Gf
publicvoid setCurrentPage(int currentPage){ ",!1m7[wF
this.currentPage = currentPage; P{u0ftyX}
} '3?\K3S4i
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/** /z}~zO
* @return Ox@sI:CT
* Returns the everyPage. 8O Soel
*/ JJ%ePgWT
publicint getEveryPage(){ X$yN_7|+
return everyPage; !H ~<
} W8]lBh5~:
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/** hEw-
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* @param everyPage / 4lvP
* The everyPage to set. gH G
*/ NOp609\^
publicvoid setEveryPage(int everyPage){ ,u/aT5\_
this.everyPage = everyPage; xKFn.qFr
} 7PkJ-JBA
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/** yR4|S2D3xn
* @return u?+Kkkk
* Returns the hasNextPage. lv]hTH 4T
*/ Op_RzZP`
publicboolean getHasNextPage(){ H=\3Jj(4
return hasNextPage; I}t#%/'YA
} &-mX ,
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/** I6Ce_|n
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* @param hasNextPage lIProF0
* The hasNextPage to set. Jej` ;I
*/ _vZ"4L+Iw+
publicvoid setHasNextPage(boolean hasNextPage){ !&"<oPjr+
this.hasNextPage = hasNextPage; t
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} Ovj^IjG-`
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/** mVR P~:+
* @return *guoWPA|Ij
* Returns the hasPrePage. ;f"0~D2
*/ YJo["Q
publicboolean getHasPrePage(){ A$w4PVS
return hasPrePage; !U5Wr+83
} ,%)6jYHR w
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/** &cu lbcz
* @param hasPrePage ' Tc]KXD6
* The hasPrePage to set. ~t~-A,1
*/ oIefw:FE,a
publicvoid setHasPrePage(boolean hasPrePage){ ;vIrGZV<
this.hasPrePage = hasPrePage; Y_QH&GZ
} [3!~PR]
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/** Rb{U+/gq
* @return Returns the totalPage. -*XCxU'
* FD8N"p
*/ 'UYR5Y>
publicint getTotalPage(){ EcCFbqS4W
return totalPage; X0n~-m"m
} D&/L:
iURk=*Z=
/** 6C+"`(u%V
* @param totalPage 1Y]TA3:
* The totalPage to set. UNkCL4N
*/ x(eb5YS
publicvoid setTotalPage(int totalPage){ ~>+]%FPv
this.totalPage = totalPage; EeF'&zE-
} dtcIC0:[
6#Q K%[1!>
} Qu]z)";7
7IjQi=#:
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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 NvvUSyk\;s
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个PageUtil,负责对Page对象进行构造: QJ7L7S
java代码: l!g]a2x*
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/*Created on 2005-4-14*/ 57g</p
package org.flyware.util.page; \}
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[mPjP%{=@
import org.apache.commons.logging.Log; @!8ZPiW<
import org.apache.commons.logging.LogFactory; d:i;z9b@to
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/** [/BE8]M~
* @author Joa Y>&Ew*Y
* !1G ."fo
*/ S!sqbLrBn
publicclass PageUtil { PfZ+PqS
q|LDo~H
privatestaticfinal Log logger = LogFactory.getLog mb!9&&2-t
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(PageUtil.class); = hN
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}ga@/>Sl&
/** S*,rGCt'T
* Use the origin page to create a new page w#g#8o>'
* @param page ]Qe{e3p;
* @param totalRecords b@2J]Ay E*
* @return jvQ*t_L
*/ H8'Z#"h
publicstatic Page createPage(Page page, int DHY@akhrK
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totalRecords){ //4Xq8y
return createPage(page.getEveryPage(), g{P%s'%*
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page.getCurrentPage(), totalRecords); pm9%%M$
} eEn;!RS)
V}zEK0n(6
/** p+Y>F\r&w
* the basic page utils not including exception -k7X:!>QHC
bHI<B)=`
handler V,[d66H=N
* @param everyPage wX*K]VMn
* @param currentPage +(+Itmx2&
* @param totalRecords 7H|$4;X^
* @return page 5Fz.Y}
*/ Q"7Gy<
publicstatic Page createPage(int everyPage, int @_LN3zP
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currentPage, int totalRecords){ <Engi!
everyPage = getEveryPage(everyPage); tu5*Qp\
currentPage = getCurrentPage(currentPage); H~E(JLcU
int beginIndex = getBeginIndex(everyPage, 1Zi,b
r]0
lo-
currentPage); 5A4&+rdU
int totalPage = getTotalPage(everyPage, 0p@k({] <
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totalRecords); Uk,gJR
boolean hasNextPage = hasNextPage(currentPage, <3j"&i]Tm*
k{<,\J
totalPage); ;-Jb1"5
boolean hasPrePage = hasPrePage(currentPage); +/ &_v^sC;
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returnnew Page(hasPrePage, hasNextPage, "XT"|KF|D
everyPage, totalPage, 1\r|g2Z
:
currentPage, b%Eei2Gm%
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beginIndex); 2 6>ZW4Z
} ?SC[G-b
#-GJ&m8
privatestaticint getEveryPage(int everyPage){ XduV+$03
return everyPage == 0 ? 10 : everyPage; E(i[o?
} EFc-foN
g9Yz*Nee<
privatestaticint getCurrentPage(int currentPage){ f
+hjC
return currentPage == 0 ? 1 : currentPage; "ax..Mh\y
} <u=4*:QE
|> _!eS\=<
privatestaticint getBeginIndex(int everyPage, int >pr=|$zk=
36n>jS&
currentPage){ X~xd/M=9^
return(currentPage - 1) * everyPage; Jx=hJ-FY
} 2mq$H_
A Z{^o4<q
privatestaticint getTotalPage(int everyPage, int #"49fMi/
raQ7.7
totalRecords){ gp-T"l
int totalPage = 0; .E@|D6$D
RO3oP1@B
if(totalRecords % everyPage == 0) -!8(bjlJ&
totalPage = totalRecords / everyPage; _A~4NW{U7
else :(_+7N[KA
totalPage = totalRecords / everyPage + 1 ; X@|&c]]
d
O~O
|Xsb
return totalPage; 1lpwZ"
} -&e92g&n
[JaS??ig
privatestaticboolean hasPrePage(int currentPage){ wlPx,UqZ
return currentPage == 1 ? false : true; qSejLh6
} /N-_FMl?
,Hgc-7g@Y
privatestaticboolean hasNextPage(int currentPage, $ F S_E
)=DGdIEt
int totalPage){ Q_vW3xz
return currentPage == totalPage || totalPage == U #~;)fZ
:>81BuMvg
0 ? false : true; nL?oTze*p
} H- p;6C<
K)_WL]RJ.4
9V.u-^o&
} \` w4|T
SAY
f'[|w
`.2hjO
BQ jK8c<
1R.4:Dn_
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。 28OWNS
M=
D\ H/
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 178Mb\8
9RwawTM
做法如下: !SKV!xH9
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;;)`c/$
{>bW>RO)
的信息,和一个结果集List: tW;:-
java代码: j8K,jZ
Xo {`]
#*>E*#?t
/*Created on 2005-6-13*/ ! <WBCclX
package com.adt.bo; ,Os? f:Y6
IooNb:(
import java.util.List; )RsM!}
]/cd;u
import org.flyware.util.page.Page; vOgC>_x7
*x>3xQq&
/** j(#%tIv
* @author Joa t]-uw-E
*/ _u}4j 9T
publicclass Result { $Q+s/4\
-]:GL>b
private Page page; 7'NS9|
[\Qr. 2
private List content; cubUq5
]h9!ei
[
/** _e!F~V.
* The default constructor eb|i3.
*/ $c&0F,
public Result(){ rNl.7O9b
super(); yA[({2%
} B ZMu[M
(.3'=n|kE
/** 4ujvD ^
* The constructor using fields ,DnYtIERo
* mceG!@t
* @param page rbqo"g`
* @param content ug`NmIQP
*/ ;PyZ?Z;
public Result(Page page, List content){ >\A8#@1
this.page = page; k#:2'!7G
this.content = content; (5$ZvXx?}
} AD('=g J
XUV!C7
/** uENdI2EY8y
* @return Returns the content.
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*/ VK3it3FI>3
publicList getContent(){ o5aLUWi-
return content; [t0rfl{.
} efz&@|KR
G&f7+e
/** lnbmo Hv
* @return Returns the page. 'YSuQP>
*/ ;,OfJ'q^
public Page getPage(){ ;\%sEcpT
return page; 8n?kZY$,
} iz"3\{aN
(!?K7<Jv
/** )yxT+g2!
* @param content IJU0[EA]F
* The content to set. y:}sD_m0W
*/ pz doqAVI
public void setContent(List content){ ,,=apyr#&
this.content = content; sP$Ks#/
} "t(wG{RxY
2}t&iG|0/
/** gd^Js1Z
* @param page _ :^7a3I
* The page to set. w36(p{#vp
*/ w>~M}Ahj
publicvoid setPage(Page page){ 8)0L2KL'
this.page = page; EA{U!b]cU
} v+1i=s2$
} K6pR8z*?
D>wZ0p b-
CV.+P-
_`a&9i
&
.gYt0raSY
2. 编写业务逻辑接口,并实现它(UserManager, '5H4z7)
K3p@$3hQ
UserManagerImpl) #2%([w
java代码: M2T| "Q"=
[B6DC`M
nwM)K
/*Created on 2005-7-15*/ h
; kfh.
package com.adt.service; )%JD8;[Jq
yFpySvj}
import net.sf.hibernate.HibernateException; q^bO*bv
);}t&}
import org.flyware.util.page.Page; F;D1F+S
mrZ`Lm#>pS
import com.adt.bo.Result; ,-rB=|w
[>w%CY<Fd
/** 5 d ;|=K
* @author Joa r[HT9
*/ w+f=RHX"{
publicinterface UserManager { G?V"SU.
QD<eQsvV
public Result listUser(Page page)throws jQtSwVDr
:%tuNJjj
HibernateException; d\]O'U)s
Bh` IXu
} R,Ml&4pZ}
T{S4|G1R6
/)V4k:#b
?y-s20Kd
wRVD_?
java代码: 30 7fBa
^Omfe
|f NMs
/*Created on 2005-7-15*/ +{rJ[J/g
package com.adt.service.impl; C{Blqf3V0
D@vMAW
import java.util.List; #@_1fE
^Rmoz1d
import net.sf.hibernate.HibernateException; ,k*F`.[
4MX7=!E
import org.flyware.util.page.Page; x N`T
import org.flyware.util.page.PageUtil; If.n(t[M9
%ejeyc
import com.adt.bo.Result; 3Xdn62[&
import com.adt.dao.UserDAO; $pFk"]=
import com.adt.exception.ObjectNotFoundException; f9']
jJ+
import com.adt.service.UserManager; 6q%ed
UED
}aZrou3E
/** sb'p-Mj
* @author Joa _pSIJ3O
*/ FDq{M?6i
publicclass UserManagerImpl implements UserManager { (2%>jg0M
5\G)Q<A]*L
private UserDAO userDAO; ]_2yiKv&
t:9
ZCu ay
/** },6*Y*?{
* @param userDAO The userDAO to set. J~dTVBx
*/ o>!JrH
publicvoid setUserDAO(UserDAO userDAO){ N5\{yV21",
this.userDAO = userDAO; #Wx=v$"
} OROqT~6G
k5X b}@
/* (non-Javadoc) !`C%Fkq
* @see com.adt.service.UserManager#listUser e\~l!f'z
{8ECNQ[]
(org.flyware.util.page.Page) Uh\]?G[G
*/ <bX 1,}?
public Result listUser(Page page)throws lJj&kVHb
DR{]sG
HibernateException, ObjectNotFoundException { 6S_y%8Fv&[
int totalRecords = userDAO.getUserCount(); 0UD"^zgY
if(totalRecords == 0) 1"$R 3@s;
throw new ObjectNotFoundException tDU}rI8?
;z0"Ox=7
("userNotExist"); oeGS
page = PageUtil.createPage(page, totalRecords); Bbs5f@E
List users = userDAO.getUserByPage(page); f+^c@0que
returnnew Result(page, users); xOM_R2Md
} 08io<c,L
*+~D+_,
} ^;64!BaK
h60\ Y 8
-eq=4N=s
uWrFunh%
}s6G!v^2""
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;/aB)JZ5=
O=`o'%K<
询,接下来编写UserDAO的代码: iUCwKpb9
3. UserDAO 和 UserDAOImpl: U IQ 6SvM
java代码: K#;txzi
)"-fHW+fy
`uhL61cMp
/*Created on 2005-7-15*/ .$^wy3:F"
package com.adt.dao; CLktNR(45
?w8pLE~E
import java.util.List; um}N%5GAa
44<v9uSK
import org.flyware.util.page.Page; _r7=&oL.Q
@e={Wy+Vm(
import net.sf.hibernate.HibernateException; uOb2npPj
)BB%4=u@~.
/** Vs|sw
* @author Joa 4[xA-
\
*/ EaCZx
publicinterface UserDAO extends BaseDAO { cb4b,Ri
1{7_ `[
publicList getUserByName(String name)throws =<>pKQ)[
j
aD!
HibernateException; -Y2&A$cM
2|
$k`I,
publicint getUserCount()throws HibernateException; h^v9|~ZJ'7
o6/Rx#A
publicList getUserByPage(Page page)throws V-:`+&S{^
fX""xTNPi
HibernateException; 9g4QVo|
!rz)bd3$
} @F~0p5I
6l<1A$BQ
!HvGlj@(|
<gR`)YF7
oq243\?Y
java代码: &1oaZY w
4 ;^g MI9
F"Uh/EO<
/*Created on 2005-7-15*/ 17|@f
package com.adt.dao.impl; N: A3kp
CN-4-
import java.util.List; |z ]aa
|}%(6<
import org.flyware.util.page.Page; >QA/Mi~R
'G52<sF
import net.sf.hibernate.HibernateException; #i@ACAgn;6
import net.sf.hibernate.Query; otoBb^Mz
B,w:DX
import com.adt.dao.UserDAO; P4i3y{$V
KU*`f{|
/** C+T&O
* @author Joa *O!T!J
*/ 7N!tp,?
public class UserDAOImpl extends BaseDAOHibernateImpl _w\Y{(k
q"P5,:W
implements UserDAO { _s2m-jm7
{(_B
/* (non-Javadoc) H\ {E%7^h-
* @see com.adt.dao.UserDAO#getUserByName fm[_@L%
x
v/]Qq
(java.lang.String) lt&$8jh
*/ OTnu{<.a
publicList getUserByName(String name)throws r[6#G2
U.HoFf+HN
HibernateException { .MzOLv
String querySentence = "FROM user in class mu 2
A% "7
\nrgAC-b
com.adt.po.User WHERE user.name=:name"; =DGn,i9
Query query = getSession().createQuery 44Q6vb?
'" ^ B&W
(querySentence); UwZu:[T6H
query.setParameter("name", name); :U!'U;uQ
return query.list(); ]jZiW1C*a
} (zjz]@qJ
bELIRM9
/* (non-Javadoc) 71JM
[2
* @see com.adt.dao.UserDAO#getUserCount() )3BR[*u*
*/ =X)Q7u".7
publicint getUserCount()throws HibernateException { ,Le&I9*%
int count = 0; Y;'VosTD
String querySentence = "SELECT count(*) FROM F_ ,L2J
;r g H}r
user in class com.adt.po.User"; x-w`KFS
Query query = getSession().createQuery j2< !z;2
)GB3=@
(querySentence); ){+.8KI
count = ((Integer)query.iterate().next zJz82jMm
i<B:
()).intValue(); 6F@zCv"w
return count; YtV |e|aD
} fG X1y
\Oi5=,
/* (non-Javadoc) DZ%g^DRZX
* @see com.adt.dao.UserDAO#getUserByPage ZMdM_i?
UOn! Y@
(org.flyware.util.page.Page) 7( yXsVq
*/ }f<fgY
publicList getUserByPage(Page page)throws [?Mc4uT{
C/{nr-V3u
HibernateException { *p" "YEN
String querySentence = "FROM user in class `G_(xN7O
fR+Ov8PCq
com.adt.po.User"; 7p
P|
Query query = getSession().createQuery 9(QU2QY
"z^BKb5
(querySentence); 2$o2.$i81
query.setFirstResult(page.getBeginIndex()) &>&dhdTQ
.setMaxResults(page.getEveryPage()); R59e&
return query.list(); 3~cS}N T
} }2-[Ki yv
z*Myokhf
} ${jA+L<J
Kj~>&WU
XR{5]lKt_
dH
^b)G4
tqff84
至此,一个完整的分页程序完成。前台的只需要调用 `f\5p+!<7R
=XZF.ur
userManager.listUser(page)即可得到一个Page对象和结果集对象 R=][>\7]}
Qh)|FQ[s$r
的综合体,而传入的参数page对象则可以由前台传入,如果用 g`%ED0aR
WHlD%u
webwork,甚至可以直接在配置文件中指定。 XD_P\z
&4mfzpK
下面给出一个webwork调用示例: [_g#x(=
java代码: 1TK #eU
D)H?=G
+Fu@I{"A
/*Created on 2005-6-17*/ ]%NO"HzF~
package com.adt.action.user; :J=+; I(UI
F'V+2,.
import java.util.List; c7FfI"7HR
#Pb7EL#c
import org.apache.commons.logging.Log; a}5vY
import org.apache.commons.logging.LogFactory; O0K@M
import org.flyware.util.page.Page; H]%mP|
^yn[QWFO
import com.adt.bo.Result; [JX}1%NA
import com.adt.service.UserService; Ff)~clIK '
import com.opensymphony.xwork.Action; N}8HK^n*
zPX=MfF
/** #U",,*2
* @author Joa <6d{k[7fz)
*/ _'?8s6 H
publicclass ListUser implementsAction{ RT.wTJS;
WU+Jo@]y
privatestaticfinal Log logger = LogFactory.getLog "}]GQt< F
EWuiaw.
(ListUser.class); _0DXQS\
beN>5coP%A
private UserService userService; "6`)vgI~
wu&|~@_s@
private Page page; <2o.,2?G
g( @$uJ
privateList users; ^Ff~j&L@{
*sc0,'0
/* +(QMy&DtS
* (non-Javadoc) f{+LCMbC6
* Vz7w{HY
* @see com.opensymphony.xwork.Action#execute() =`7#^7Q9
*/ J{GFb
publicString execute()throwsException{ Ovl?j&8
Result result = userService.listUser(page); oP|pOs\$p
page = result.getPage(); -7Aw
s)
users = result.getContent(); a0V8L+v(
return SUCCESS; DWm;&RPJ
} <tu[cA>
'?vgp
/** T>%uRK$
* @return Returns the page. 0%A(dJA6
*/ Qq;m"M /
public Page getPage(){ wB1|r{
return page; U&Sbm~Qi
} K=!ZI/+ju
2-cU -i4
/** ^H\-3/si*
* @return Returns the users. <WHs
*/ "a0u-}/D
publicList getUsers(){ SBN_>;$c5}
return users; f}9PEpa,Z
} H/^TXqQ8
lH,]ZA./
/** XoH[MJC
* @param page *Lb(urf
* The page to set. 0?5%
*/ Fl#VKU3h
publicvoid setPage(Page page){ n&3iv^
this.page = page; VtzyB
} RV#uy]
Zs3]|bUR
/** @T,H.#bL
* @param users [)J49
* The users to set. Vlp*'2VO
*/ [MQJ71(3
publicvoid setUsers(List users){ [o[v"e\w
this.users = users; cmr6,3_
} 08K.\3
+EiUAs~H
/** -}N\REXE
* @param userService } TX'Z?Lq
* The userService to set. D|Ih e%w-
*/ k`2B9,z
publicvoid setUserService(UserService userService){ yZ?_q$4kEI
this.userService = userService; k^dCX+
} ?{.b9`
} 8x^H<y=O
mtWx ?x
v_@#hf3
3 R:7bex
Qq FfR#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, xV n]m9i
!s[j1=y
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 6(<~1{
X%
]=86[A-2N
么只需要: UTK.tg
java代码: ;qVEI/
>;' 1k'
;@ll
<?xml version="1.0"?> m)[wZP*e
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork h@>rjeY@
G5QgnxwP2
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /nMqEHCyg
X!MfJ^)q
1.0.dtd"> Xv5Ev@T
&PQ{e8w
<xwork> e/HX,sf_g
ZAo)_za&mH
<package name="user" extends="webwork- Y%?!AmER
W-]yKSob
interceptors"> |E_+*1l q.
r/q1&*T
<!-- The default interceptor stack name T`'3Cp$q
d$?n6|4
--> ,f/IG.
<default-interceptor-ref ?j4,^K3
)oxP.K8q)U
name="myDefaultWebStack"/> sei!9+bZr
bU4+PA@$
<action name="listUser" <T.3ZZ%
h'YcNkM
2>
class="com.adt.action.user.ListUser"> Aya;ycsgE
<param /hEGk~
$hE'b9qx
name="page.everyPage">10</param> FO'.
a
<result ZV<y=F*~f
Ff#N|L'9_
name="success">/user/user_list.jsp</result> fN*4(yw
</action> ubC JZ"!
aXK%m
</package> tv=FFfQ
E?q'|f
</xwork> 1'U%7#;E
p_40V%y^
;k41+O:f@
_]r)6RT
wgR@M[]o;
-WW!V(~p
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ]'ApOp
CD<u@l,1
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 g-V\s&}
dBq,O%$oq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 h9n<ped`A;
?L#SnnE
c{4nW|/W
F=T.*-oS3
eg~^wi
我写的一个用于分页的类,用了泛型了,hoho q}A3"$-F
+q=jB-eIx
java代码: }9Dv\"t5
3]]6z K^i
!RUo:b+
package com.intokr.util; \-iUuHP
cp?P@-
import java.util.List; z?_}+
0_zSQn9c
/** AA& dZjz
* 用于分页的类<br> MLIQ 8=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> O>F.Wf5g
* I8%'Z>E(
* @version 0.01 B)cb}.N:
* @author cheng NizJq*V>
*/ 98}vbl31j
public class Paginator<E> { ~V-
o{IA
privateint count = 0; // 总记录数 A`/7>'k/q[
privateint p = 1; // 页编号 BMj&*p8R
privateint num = 20; // 每页的记录数 ]<_!@J6k
privateList<E> results = null; // 结果 %C][E^9
np>!lF:
/** KeOBbe
* 结果总数 K$v Rk5U
*/ +bd{W]={
publicint getCount(){ ~u`! Gi
return count; EkAqFcKLq
} yrYaKh
,v5>sL
publicvoid setCount(int count){ &+{xR79+&
this.count = count; 0|Ft0y`+
} !9cP NIi
+~{nU'
/** 0m!ZJH e
* 本结果所在的页码,从1开始 dZYJ(7%
* ^Jpd9KK
* @return Returns the pageNo. Fl>j5[kLZ
*/ G}xBYc0b
publicint getP(){ N)y;owgo
return p; l
YA+k5
} %|* y/m
#YVDOR{z
/** 1;[
<||K
* if(p<=0) p=1 '0M0F'R
* >Ez}r(QQ^
* @param p daJ-H
*/ m/B9)JzY
publicvoid setP(int p){ ZS>/ 5
if(p <= 0) n?fC_dy
p = 1; H.~+{jTr
this.p = p; rtOW-cz
} p
8Hv7*
Y tj>U
/** ]
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* 每页记录数量 2xBGs9_Y
*/ JJOs
L!@
publicint getNum(){ 2-2LmxLG
return num; W]7?;#Hpk
} TEyPlSGG
evk
<<zi
/** }33Au-%*
* if(num<1) num=1 .%h_W\M<l
*/ U]&%EqLS
publicvoid setNum(int num){ -*j;
if(num < 1) BeCr){,3
num = 1; ]= D
this.num = num; *4\ub:9
} #!j&L6
sJYX[
/** jo:p*Q"F
* 获得总页数 bbA<Zp
*/ ~2;y4%K
publicint getPageNum(){ ?&^l8gE
return(count - 1) / num + 1; uV\#J{'*
} 3VgH*vAU}
I`lH6hHp
/** ~%q e,
* 获得本页的开始编号,为 (p-1)*num+1 Jq@LZ2^
*/ .qP
zd(<T7
publicint getStart(){ n8C {Okr
return(p - 1) * num + 1; !}m8]&
} .SFwjriZ
R
dzIb-
/** V:np cKpu
* @return Returns the results. %j`]x
-aOz
*/ imuHSxcaV
publicList<E> getResults(){ ~.SU$
return results; nW[aPQ[R
} .^W0;ISX
p{u}t!`!d
public void setResults(List<E> results){ E_*T0&P.P
this.results = results; ^U1+D^AJ
} yrb%g~ELGn
I*t}gvUt9
public String toString(){ _J`M>W)8
StringBuilder buff = new StringBuilder '7%9Sqx
?q7Gs)B=^'
(); -O6o^Dk
buff.append("{"); 8;bOw
buff.append("count:").append(count); 4K,&Q/Vdd7
buff.append(",p:").append(p); SxyFFt
buff.append(",nump:").append(num); %|||M=akk
buff.append(",results:").append 7]
H4E.(l
#7) 6X:/O
(results); /;J;,G`?
buff.append("}"); HxAa,+k
return buff.toString(); z(` kWF1<
} OTm"Iwzu@
Ds$;{wl#x
} F U%b"gP^
6
>2!
kM7
D=+sD"<|