Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uk WL3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .#sX|c=W
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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 i&m6;>?`
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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 #68$'Rl"o1
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分页支持类: Q;y4yJ$wI
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java代码: YsiH=x
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package com.javaeye.common.util; ow`F 7
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import java.util.List; WSU/Z[\`H
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publicclass PaginationSupport { Q9p7{^m&E
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publicfinalstaticint PAGESIZE = 30; ~z41$~/
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privateint pageSize = PAGESIZE; mo4F\$2N
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privateList items; zcOm"-E-
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privateint totalCount; .bV^u
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privateint[] indexes = newint[0]; JAMV@
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privateint startIndex = 0; r-WX("Vvh
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public PaginationSupport(List items, int F!?f|z,/
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totalCount){ ox.kL
setPageSize(PAGESIZE); K'E)?NW69
setTotalCount(totalCount); EN}4-P/5
setItems(items); G:|]w,^i
setStartIndex(0); >x~Qa@s;
} 0&kmP '
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public PaginationSupport(List items, int BGH'&t_5
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totalCount, int startIndex){ d}?KPJ{
setPageSize(PAGESIZE); U? U3?Y-k`
setTotalCount(totalCount); X
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setItems(items); <?;KF2A({
setStartIndex(startIndex); PRyzvc~
} VggSDb
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public PaginationSupport(List items, int {SZv#MrK
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totalCount, int pageSize, int startIndex){ g^=Ruh+
setPageSize(pageSize); sQrM"i0Y>
setTotalCount(totalCount); PF)s>
setItems(items); 7''iT{-[p
setStartIndex(startIndex); ;3Z?MQe"NQ
} |hDN$By
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publicList getItems(){ ]gA2.,)}D
return items; #c/K.?
} lF7".
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publicvoid setItems(List items){ NP!LBB)=Y
this.items = items; g>b{hkIXg
} Az?^4 1r8
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publicint getPageSize(){ d,'gh4C
return pageSize; 4]
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} jQfnc:'
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publicvoid setPageSize(int pageSize){ 80gOh:
this.pageSize = pageSize; yS?5&oMl
} ka`}lR
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publicint getTotalCount(){ `oO*ORq&
return totalCount; Ak}`zIo
} -\Z`+k Y?p
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publicvoid setTotalCount(int totalCount){ ;D(6Gy9~
if(totalCount > 0){ .F _u/"**
this.totalCount = totalCount; 9A`^ (
int count = totalCount / Z;dR:|%)
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pageSize; k
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if(totalCount % pageSize > 0) ']^]z".H
count++; @aB7dtM
indexes = newint[count]; "{bc2#F
for(int i = 0; i < count; i++){ nF,zWr[x
indexes = pageSize * ),%@X
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i; %_39Wa
} ['6Sq@c)
}else{ \2Q#'
this.totalCount = 0; R=iwp%c(
} ?2gXF0+~Y2
} 3"Kap/[h
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publicint[] getIndexes(){ R_:lp\S&
return indexes; (@*%moo
} [KW)z#`*
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publicvoid setIndexes(int[] indexes){ tI.ho
this.indexes = indexes; .\
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} Pvm pWa
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publicint getStartIndex(){ Q}
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return startIndex; TTo?BVBK
} T#Z#YM k
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publicvoid setStartIndex(int startIndex){ m_;XhO
if(totalCount <= 0) I;{Ua*
this.startIndex = 0; W6u(+P]("
elseif(startIndex >= totalCount) ?. L]QU
this.startIndex = indexes TyR@3H
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[indexes.length - 1]; 4dI`
elseif(startIndex < 0) Hm~.u.)\.
this.startIndex = 0; iQiXwEAi[
else{ cA90FqUH
this.startIndex = indexes Yqt~h
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[startIndex / pageSize]; (;N#Gqb6l
} =ATQ2\T$m
} \MAv's4b@
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publicint getNextIndex(){ 83)m#
int nextIndex = getStartIndex() + $?OQtz@
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pageSize; [E9_ZdBT
if(nextIndex >= totalCount) Z|3[Y@c\
return getStartIndex(); {{ 1qkG9$
else oRmA\R*
return nextIndex; YTfi g{a
} 2H~E~6G
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publicint getPreviousIndex(){ 5VGZ5,+<<
int previousIndex = getStartIndex() - J8&0l&~6
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pageSize; ~UwqQD1p
if(previousIndex < 0) }fhGofN$e
return0; h~=~csya:
else "2"2qZ*h}
return previousIndex; F]RZP/D`
} @[TSJi
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} DeQZDY //
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抽象业务类 Saks~m7,
java代码: C&.Q|S2_
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/** @Fb
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* Created on 2005-7-12 zRm@ |IT
*/ }%3i8e
package com.javaeye.common.business; [q|8.>sB
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import java.io.Serializable; xr^fP~V|)0
import java.util.List; Ye/Y<Ij
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import org.hibernate.Criteria; f!B\X*|
import org.hibernate.HibernateException; [QwqP=-6
import org.hibernate.Session; V$ "]f6
import org.hibernate.criterion.DetachedCriteria; UrdSo"%
import org.hibernate.criterion.Projections; ERfSJ
import -Y>QKS
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org.springframework.orm.hibernate3.HibernateCallback; VH~ZDZ1P
import K/!>[d
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org.springframework.orm.hibernate3.support.HibernateDaoS EB
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upport; $N4i)>&T2
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import com.javaeye.common.util.PaginationSupport; TTSq }sb}
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public abstract class AbstractManager extends 4B-+DH>{6
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HibernateDaoSupport { .h@bp1)l
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privateboolean cacheQueries = false; +"VXw2R_e
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privateString queryCacheRegion; 0E^S!A7
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publicvoid setCacheQueries(boolean i MF-TR
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cacheQueries){ 0w6"p>s>c
this.cacheQueries = cacheQueries; JiX-t\V ~
} q =26($
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publicvoid setQueryCacheRegion(String 0He^r
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queryCacheRegion){ Nkk+*(Z
this.queryCacheRegion = %p^`,b}
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queryCacheRegion; (l)r.Vj
} Jwbb>mB!
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publicvoid save(finalObject entity){ T{*!.+E
getHibernateTemplate().save(entity); W"5VqN6v
} KK/siG~O
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publicvoid persist(finalObject entity){ 7"Q;Yi2(
getHibernateTemplate().save(entity); Bv^5L>JZ/
} F>aaUj
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publicvoid update(finalObject entity){ Y58et9gRO
getHibernateTemplate().update(entity); piAFxS<6
} v.>95|8
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publicvoid delete(finalObject entity){ ov|pXi<e
getHibernateTemplate().delete(entity); ,BlNj^5f
} knRs{1}Pw{
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publicObject load(finalClass entity, :a)` iJnb
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finalSerializable id){ k1HCPj
return getHibernateTemplate().load *;~i\M9_
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(entity, id); 17!<8vIV$C
} ")3$. '5Dg
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publicObject get(finalClass entity, ;Lk07+3G
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finalSerializable id){ 1m<8M[6u
return getHibernateTemplate().get JQA]O/|N
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(entity, id); --F6n/>
} ZP"Xn/L
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publicList findAll(finalClass entity){ bfKF6
return getHibernateTemplate().find("from GNoUn7Y
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" + entity.getName()); :E2 ww`
} 1oL3y;>iL
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publicList findByNamedQuery(finalString B[r04YGh
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namedQuery){ G`,M?lmL
return getHibernateTemplate +sx$%N
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().findByNamedQuery(namedQuery); A0H6}53, $
} QJU\YH%}
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publicList findByNamedQuery(finalString query, o|y1 m7X
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finalObject parameter){ ZO]P9b
return getHibernateTemplate *+j r? |
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().findByNamedQuery(query, parameter); B<&g
} nc.:Wm6Mj
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publicList findByNamedQuery(finalString query, /q?gpy
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finalObject[] parameters){ B$_-1^L
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return getHibernateTemplate !qug^F
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().findByNamedQuery(query, parameters); N)
} y`J8hawp
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publicList find(finalString query){ z#/"5 l
return getHibernateTemplate().find 3?<LWrhV3
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(query); P$6Pe>3
} :dwP
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publicList find(finalString query, finalObject Fq'Ds[wd5
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parameter){ FA}y"I'W
return getHibernateTemplate().find ;.3
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(query, parameter); P}"uC`036
} kp^q}iS
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public PaginationSupport findPageByCriteria &M6Zsmo
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(final DetachedCriteria detachedCriteria){ m`Pk )c0
return findPageByCriteria Sn[/'V^$a
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); W 'R^GIHs
} T
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public PaginationSupport findPageByCriteria a( SJ5t?-2
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(final DetachedCriteria detachedCriteria, finalint _Oy;:XN
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startIndex){ -v$ q8_$m"
return findPageByCriteria #hXxrN
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(detachedCriteria, PaginationSupport.PAGESIZE, TVAa/_y2`
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startIndex); t@q==VHF
} {pC$jd>T
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public PaginationSupport findPageByCriteria ,iXQ"):!OB
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(final DetachedCriteria detachedCriteria, finalint j eyGIY
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pageSize, 'ji|'x T
finalint startIndex){ oObQN;A@6
return(PaginationSupport) xMFEeSzl>S
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getHibernateTemplate().execute(new HibernateCallback(){ g1) ZjABV
publicObject doInHibernate ~%@1-
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(Session session)throws HibernateException { $.zd,}l@L
Criteria criteria = uj+{
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detachedCriteria.getExecutableCriteria(session); ':]Hj8t_
int totalCount = M"yOWD~s~
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((Integer) criteria.setProjection(Projections.rowCount GIhFOK
'u6n,yRm
()).uniqueResult()).intValue(); a&u!KAQ
criteria.setProjection %uvA3N>
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(null); HJt
'@t=Ak
List items = 0/uy'JvWru
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criteria.setFirstResult(startIndex).setMaxResults Cng_*\=O
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(pageSize).list(); |\W~+}'g~
PaginationSupport ps = ,JfP$HJ
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new PaginationSupport(items, totalCount, pageSize, d=dHY(ms]
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startIndex); ahFK^ #s
return ps; dnkHx
} Vze vOS
}, true); S_38U
} dF*M"|[
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public List findAllByCriteria(final I8k+Rk*
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DetachedCriteria detachedCriteria){ K$O2
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return(List) getHibernateTemplate zF(abQ0
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().execute(new HibernateCallback(){ ~RV"_8`V9
publicObject doInHibernate &a)d,4e<M
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(Session session)throws HibernateException { X$_pDF&\z
Criteria criteria = S3&n?\CO:
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detachedCriteria.getExecutableCriteria(session); *:ErZ UyQM
return criteria.list(); )nrYxxN
} )>@%;\qV
}, true); ]~!CJ8d
} 5F#FC89Kk
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public int getCountByCriteria(final -Ua&/Yd/}
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DetachedCriteria detachedCriteria){ ^
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Integer count = (Integer) JF=T_SH^U
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getHibernateTemplate().execute(new HibernateCallback(){ I@TH^8(
publicObject doInHibernate \i\>$'f*z
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(Session session)throws HibernateException { ^tIYr<I
Criteria criteria = <k{_YRB
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detachedCriteria.getExecutableCriteria(session); )TEod!]
return >E3-/)Ti
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criteria.setProjection(Projections.rowCount uPE Ab2u="
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()).uniqueResult(); 8C@6
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} f,ZJFb98
}, true); .o]9
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return count.intValue(); 6C\WX(@4
} A(H2Gt
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} U>@AE
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用户在web层构造查询条件detachedCriteria,和可选的 umCmxmr&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _9q byhS7
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PaginationSupport的实例ps。 fYpJ2y-sA
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ps.getItems()得到已分页好的结果集 | GN/{KH]
ps.getIndexes()得到分页索引的数组 'p@m`)Z
ps.getTotalCount()得到总结果数 )0g!lCfb
ps.getStartIndex()当前分页索引 <p-@XzyE
ps.getNextIndex()下一页索引 bh#6yvpMR
ps.getPreviousIndex()上一页索引 db&!t!#,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Y#6LNI
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 H )CoByaj
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一下代码重构了。 hT `&Xb
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我把原本我的做法也提供出来供大家讨论吧: e)m6xiZ
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首先,为了实现分页查询,我封装了一个Page类: 1Zi` \N4T
java代码: Y0J:c?,
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/*Created on 2005-4-14*/ @"wX#ot
package org.flyware.util.page; /a)^)
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/** P1Eg%Y6
* @author Joa Q)lD2
* _dW#[TCF
*/ #{#k;va
publicclass Page { Ro4!y:2|
e/#6qCE
/** imply if the page has previous page */ 1$`|$V1
privateboolean hasPrePage; L\5:od[EP
,Q.[Lc=w
/** imply if the page has next page */ TjI&8#AWBA
privateboolean hasNextPage; *'tGi_2?(
ZkO2*;
/** the number of every page */ Z^=(9:
privateint everyPage; }E[vW
dvz6
/** the total page number */ 3\{\ al
privateint totalPage;
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/** the number of current page */ 4mtO"'|
privateint currentPage; ?$uEN_1O\@
rixVIfVF
/** the begin index of the records by the current *YGj^+
+$#XV@@~
query */ aof'shS8
privateint beginIndex; b5I 8jPj4c
gm=C0Sp?
wy{sS}
/** The default constructor */ /3VO!V]u
public Page(){ PgHmOs
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} ,4 q^(
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/** construct the page by everyPage 7I@df.rf6J
* @param everyPage {u9n?Z%
* */ IXlk1tHN4I
public Page(int everyPage){ BE],PCpPr
this.everyPage = everyPage; 0c1=M|2
} 8~~ k?
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/** The whole constructor */ BwGOn)KL
public Page(boolean hasPrePage, boolean hasNextPage, ksOc,4A
R y(<6u0
B&<5VjZ\
int everyPage, int totalPage, MgN;[4|[h
int currentPage, int beginIndex){ tF 7u-
this.hasPrePage = hasPrePage; *5?Qam3
this.hasNextPage = hasNextPage; |T/s>OW
this.everyPage = everyPage; p$= 3$I
this.totalPage = totalPage; S3$C#mHX
this.currentPage = currentPage; Om>?"=yD E
this.beginIndex = beginIndex; g{uiY|
} bj0<A
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/** ShvC4Xb 0
* @return o|c&$)m
* Returns the beginIndex. 5wE6 gRJ
*/ nh80"Ny5
publicint getBeginIndex(){ 3)9e-@
return beginIndex; !'IZr{Y>
} 'HCRi Z<
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/** 49O_A[(d
* @param beginIndex =<)/lz] H
* The beginIndex to set. E>gLUMG$
*/ A7&/3C6{H
publicvoid setBeginIndex(int beginIndex){ UV av^<_
this.beginIndex = beginIndex; L<XX?I\p
} [+#k+*1*o
\
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/** wZbT*rU
* @return u$aN~6HG
* Returns the currentPage. SG&H^V8
*/ f)gV2f0t
publicint getCurrentPage(){ yx6^ mis4
return currentPage; `[XH=-p
} 0;,Y_61
;=E}PbZt2
/** HZS.%+2
* @param currentPage m!!;CbPo
* The currentPage to set. 6 b?K-)kL
*/ R/Sm
publicvoid setCurrentPage(int currentPage){ [u J<]
this.currentPage = currentPage; [D(JEO@ :
} V$;`#J$\b
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/** O U9{Y9e
* @return r2PN[cLu|
* Returns the everyPage. (2"4PU8
*/ -*Qg^1]i+
publicint getEveryPage(){ 1=E}X5
return everyPage; ,?Vxcr
} +u t%C.1
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/** n<HF]
* @param everyPage yp@cn(:~
* The everyPage to set. UfV {m
*/ QwF.c28[
publicvoid setEveryPage(int everyPage){ p]Qe5@NT
this.everyPage = everyPage; a9_2b}t
} e8egxm
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/** PJe\PGh
* @return m7XN6zX
* Returns the hasNextPage. %u<r_^w5
*/ {!{T,_ J
publicboolean getHasNextPage(){ pCa~:q*85
return hasNextPage; ^YfAsBs&
} Z/v )^VR
8^^ehaxy
/** 8JW0;H<
* @param hasNextPage d4Y[}Fcp+
* The hasNextPage to set. 3O2vY1Y2
*/ T2mZkK?rA
publicvoid setHasNextPage(boolean hasNextPage){ '=Jz}F <
this.hasNextPage = hasNextPage; Bxj4rC[
} dr(e)eD(R>
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/** /^&$ma\
* @return /jq"r-S"
* Returns the hasPrePage. irjHPuhcG
*/ akHQ&+[j
publicboolean getHasPrePage(){ |L-- j
return hasPrePage; Aqg$q* Y
} ?9 `T_,
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/** ,p\*cHB9
* @param hasPrePage ,pkzNe`F
* The hasPrePage to set. `fVzY"Qv k
*/ cRf;7G
publicvoid setHasPrePage(boolean hasPrePage){ ~Sd,Tu%:
this.hasPrePage = hasPrePage; 5VfpeA`
} y4!fu<[i
o5Knot)Oy
/** $Df1t
* @return Returns the totalPage. +s [_
4
* soKR*gJ,
*/ a{?>F&vnU
publicint getTotalPage(){ o+R(ux"
return totalPage; I4c%>R
} )_kEy>YscZ
8@T0]vH&
/** G~Y#l@8M+
* @param totalPage Xa&:Hg<
* The totalPage to set. AJzm/,H
*/ *y>|
publicvoid setTotalPage(int totalPage){ 6skd>v UU
this.totalPage = totalPage; nXxnyom,
} )%!X,
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} R/^;,.
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ?C6`
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个PageUtil,负责对Page对象进行构造: xlW>3'uHfa
java代码: Me;Nn$'%
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/*Created on 2005-4-14*/ uuCVI2|
package org.flyware.util.page; ,l\D@<F
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import org.apache.commons.logging.Log; VC!g,LU|-
import org.apache.commons.logging.LogFactory; b1ZHfe:
2Ju,P_<dt
/** 6|%HCxWO
* @author Joa Ax!fvcsN
* O}7aX '
*/ \l 3M\$oS>
publicclass PageUtil { |e3YTLsI
RWn#"~
privatestaticfinal Log logger = LogFactory.getLog MpJx>0j/J
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(PageUtil.class); bW'Y8ok[v
/ pR,l5
/**
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* Use the origin page to create a new page r8L'C
* @param page B#4 J![BX
* @param totalRecords e}L(tXZ
* @return yhyh\.
*/ )#Y:Bj7H@2
publicstatic Page createPage(Page page, int P~"""3de4
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totalRecords){ 7|?Ht]
return createPage(page.getEveryPage(), 6r,zOs-I]
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page.getCurrentPage(), totalRecords); m$q*
} u #7AB>wi{
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/** jbTyM"Y
* the basic page utils not including exception j !`2Z@
zU};|Zw
handler V0:db
* @param everyPage VU|Cct&)
* @param currentPage I~c}&'V
* @param totalRecords e?-LB
* @return page G@S'_
*/ 11yS2D
publicstatic Page createPage(int everyPage, int u+8?'ZT,
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currentPage, int totalRecords){ Al]z=
everyPage = getEveryPage(everyPage); k:zGv
currentPage = getCurrentPage(currentPage); +;;pM[U
int beginIndex = getBeginIndex(everyPage, m^,3jssdA
wijY]$
currentPage); %w6lNl
int totalPage = getTotalPage(everyPage, e9?y0vT//
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totalRecords); 9'JkLgz;d+
boolean hasNextPage = hasNextPage(currentPage, DzCb'#
ymyk.#Z<%
totalPage); |n&EbOmgf
boolean hasPrePage = hasPrePage(currentPage); ^kj%Ekt7
,1e@Y~eZ
returnnew Page(hasPrePage, hasNextPage, >(a/K2$*1
everyPage, totalPage, HLM"dmI
currentPage, = G3A}
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M
beginIndex); 2c<phmiK
} *r]#jY4qx
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privatestaticint getEveryPage(int everyPage){ [x|{VJ(h
return everyPage == 0 ? 10 : everyPage; &,`P%a&k
} Aaix?
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privatestaticint getCurrentPage(int currentPage){ h%@#jvh?4
return currentPage == 0 ? 1 : currentPage; vweD{\b
} =").W \,
eM`"$xc
Oe
privatestaticint getBeginIndex(int everyPage, int aA.TlG@zP
y<5xlN(+v
currentPage){ uM~j
return(currentPage - 1) * everyPage; #/`V.jXt>
} M3
$MgsN:
cb~m==G
privatestaticint getTotalPage(int everyPage, int RpY#_\^hI
_u`W$EG
L
totalRecords){ tMy@'nj
int totalPage = 0; $eBE pN
7gQ~"Q
if(totalRecords % everyPage == 0) I^6zUVH
totalPage = totalRecords / everyPage; Q}jl1dIq
else ?2b9N ~
totalPage = totalRecords / everyPage + 1 ; [VP~~*b
3^zOG2
return totalPage; %@FTg$
} hYN b9^
ysiBru[u
privatestaticboolean hasPrePage(int currentPage){ oMi"X"C:q
return currentPage == 1 ? false : true; ,!4(B1@
} /fc@=CO
0qV!-i
privatestaticboolean hasNextPage(int currentPage, {GiR-q{t
8~|PZ,oZ
int totalPage){ re/l5v,|3
return currentPage == totalPage || totalPage == Z`b{r;`m8
^T|~L<A3
0 ? false : true; p( Q5!3C0q
} _\LAWQ|M4[
&6L{1
r 6STc,%5
} +d736lLe%
fhmqO0
fm\IQqIK%
pJ5Sxgv{;
DFt1{qS8@u
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。 y(8AxsROp
mko<J0|4
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 qyuU
`=Hh5;ep
做法如下: y85/qg)H^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #SRGVa`x
ZOG6
的信息,和一个结果集List: y8un&LP
java代码: x*[\$E`v
/wL}+
\6xVIQ& 0
/*Created on 2005-6-13*/ >%.6n:\rG
package com.adt.bo; PQ|kE`'
}ya9 +?I
import java.util.List; 9Qb_BNUo
yggQ4y6
import org.flyware.util.page.Page; #^v|u3^DD
GRb"jF>ut
/** *eytr#0B-
* @author Joa [x5T7=
*/ >LwZ"IEV
publicclass Result { T)]5k3{
q8.K-"f(Q
private Page page; MDS;qZx=
0>m-J
private List content; aQaO.K2
.4~n|d>z
/** \0m[Ch}~ey
* The default constructor 70L{u+wIy
*/ </|IgN$w`
public Result(){ *O|Z[>
super(); y!Q&;xO+!
} W^q;=D6uh
BXVmt!S5F
/** [=-?n6
* The constructor using fields ~fE@]~f>
* _d&FB~=
* @param page 5TVDt
* @param content },'2j
*/ hof:+aW
public Result(Page page, List content){ n=n!Hn
this.page = page; _.OajE\T
this.content = content; ^'~+ w3M@
} _rK}~y=0
b&Qj`j4]ZM
/** jnX9] PkJ
* @return Returns the content. ]z,W1Zs?
*/ &<-Sxjj
publicList getContent(){ <5A(rDij
return content; k#%BxT
} mh!;W=|/"
<IGQBu#ZH
/** 7%9Sz5z
* @return Returns the page. B]q
&?~
*/ ~&=-*
public Page getPage(){ S\
~Wpf
return page; U&|=dH]-
} GM{m(Y
$cFanra
/** jAmAT/ 1
* @param content VC\43A,9
* The content to set. O/>$kG%ge
*/ AS[cz!
>
public void setContent(List content){ 1y l2i|m+
this.content = content; 52BlFBNV
} 2Tt@2h_L
Bhl@\Kq
/** o-B9r+N
* @param page IDb|J%e^P
* The page to set. ,YJ\
$?
*/ Q_xE:#!;
publicvoid setPage(Page page){ yw2^kk93|
this.page = page; c-!rJHL`
} T%Vii*?M
} 1K&z64Q5J
[J0L7p*6
Y!v `0z
G:$wdT(u
w%)=`'s_
2. 编写业务逻辑接口,并实现它(UserManager, 6|t4\'
BCk$FM@
UserManagerImpl) E%
Ce/n
java代码: nk]jIRy^T
Z+@"
2P~zYdjS
/*Created on 2005-7-15*/ @!&\Z[",
package com.adt.service; \aQBzEX
]L%qfy4
import net.sf.hibernate.HibernateException; &C<B=T"I
|_8-3
import org.flyware.util.page.Page; ,2/qQD n/
a1B_w#?8
import com.adt.bo.Result; 0n|op:]BHM
bN@V=C3
/** &Jv j@,>$d
* @author Joa wX" 6 S:
*/ 5zX;/n~
publicinterface UserManager { UHF.R>Ry
&aldnJ
public Result listUser(Page page)throws /pZLt)=P
gX5I`mm
HibernateException; 2c@R!*
xWD=",0+
} `h/j3fmX?
[S9T@Q
R3<>]/1p|P
c 's=>-X
7-.YVM~R
java代码: ?N<* ATCL
*r$Yv&c,
k5]s~*,0
/*Created on 2005-7-15*/ e'mm4 2
package com.adt.service.impl; !
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snOd
3Bw
import java.util.List; v-J*PB.0p
So\(]S
import net.sf.hibernate.HibernateException; Q5b?-
P
h.ojj$f,
import org.flyware.util.page.Page; i)g=Lew
import org.flyware.util.page.PageUtil; mK5<;$
|\%[e@u
import com.adt.bo.Result; kMAQHpDD
import com.adt.dao.UserDAO; rY_)N^B|nF
import com.adt.exception.ObjectNotFoundException; KlDW'R$
import com.adt.service.UserManager; r4k=i4
uOc:^
/** )uiYu3 I
* @author Joa Lnbbv
*
*/ fDhV
*LqW
publicclass UserManagerImpl implements UserManager { U0q{8 "Pl
LCx{7bN1ro
private UserDAO userDAO; ?Ko)AP
:t-a;Q;
/** |g M|>
* @param userDAO The userDAO to set. $]Kgs6=r
*/ Ol6jx%Je`
publicvoid setUserDAO(UserDAO userDAO){ &duWV6Acw
this.userDAO = userDAO; XYhN;U}Z
} at]=SA
>{p&_u.r-
/* (non-Javadoc) P%
_cIR
* @see com.adt.service.UserManager#listUser I?LJXo \O
sx IvL7jl
(org.flyware.util.page.Page) j+"i$ln+s
*/ NypM+y
public Result listUser(Page page)throws hJ\IE?+
1r;]==
HibernateException, ObjectNotFoundException { k'E3{8<!
int totalRecords = userDAO.getUserCount(); Mh"DPt9@J
if(totalRecords == 0) %yX?4T;b
throw new ObjectNotFoundException 'd 4I/
S.1\e"MfI
("userNotExist"); [ Hw
page = PageUtil.createPage(page, totalRecords); rXc-V},az8
List users = userDAO.getUserByPage(page); L|.q19b*
returnnew Result(page, users); 5wYYYo=
} =/Pmi_
\B) a57
} mIgc)"
+>h}Uz
B/.+&AJw
*F0O*n*7W
g*?)o!_*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 S7]\tw_L)
EITA[Ba B`
询,接下来编写UserDAO的代码: L)W1bW}
3. UserDAO 和 UserDAOImpl: b9Jah
java代码: ]Ir{9EE
v
ZDuP|" ^
(T:OZmEO.
/*Created on 2005-7-15*/ XG FjqZr`
package com.adt.dao; oU`8\n](
<"F\&M`G
import java.util.List; @zo}#.g
wZB:7E%
import org.flyware.util.page.Page; C4wJSQl_I
)Be?axI
import net.sf.hibernate.HibernateException; d5h]yIz^
3<.]+ukm
/** (?R;u>
* @author Joa TP7'tb
*/ IX@g].)C
publicinterface UserDAO extends BaseDAO { "~- H]9
QP/%+[E.
publicList getUserByName(String name)throws `2N&{(
@a-u_|3q
HibernateException; 8w1TX [b
pa4,W!t
publicint getUserCount()throws HibernateException; [P~6O>a5p
"c5C0 pK0
publicList getUserByPage(Page page)throws ZI.;7G@|
ZS&>%G
HibernateException; aDEz|>q
7OuzQzhcK
} Tj5G
/H>
n.9k<
#=@H-ZuD7
+/
s2;G
rHe*/nN%*
java代码: M]9oSi
"9F]Wv/
R-odc,P=
/*Created on 2005-7-15*/ /8m2oL\<
package com.adt.dao.impl; wkNf[>jX?
hLF+_{\C|
import java.util.List; 0zH^yx:ma
ybnq;0}$
import org.flyware.util.page.Page; 5A| 4
vwy10PlqL
import net.sf.hibernate.HibernateException; UrAg*v!Qy
import net.sf.hibernate.Query; .gY}}Q
6x18g(KbP
import com.adt.dao.UserDAO; X^2 04K%:
C- 25\
/** )gM3,gSS
* @author Joa "s[Y$!#
*/ ;/tZsE{
public class UserDAOImpl extends BaseDAOHibernateImpl Qdepzo>E
m
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implements UserDAO { dzA5l:5
IX/FKSuq
/* (non-Javadoc) $BIQ#T>qK
* @see com.adt.dao.UserDAO#getUserByName D2hEI2S
OPm?kr
(java.lang.String) g7*"*%v 2
*/ F\pw0^K;N
publicList getUserByName(String name)throws >R|*FYam
;VQFz&Q$u
HibernateException { \Xy]z
String querySentence = "FROM user in class O[nl#$w
`D2wlyqO6
com.adt.po.User WHERE user.name=:name"; &!)F0PN:u
Query query = getSession().createQuery -Vj'QqZ
9a.r(W[9
(querySentence); NpmPm1Ix .
query.setParameter("name", name); Znl&.,c)
return query.list(); Y-8qAF?SJ]
} 5Gj?'Wov9
_-NS-E
/* (non-Javadoc) 6yIl)5/=
* @see com.adt.dao.UserDAO#getUserCount() WW.\5kBl8
*/ L,@OOBD
publicint getUserCount()throws HibernateException { c k~gB
int count = 0; >)Ih[0~M
String querySentence = "SELECT count(*) FROM ONx|c'0g
XTIRY4{
d
user in class com.adt.po.User"; lHYu-}TNP
Query query = getSession().createQuery ~&E|;\G
"|1MJuY_6
(querySentence); 6k#H>zY,
count = ((Integer)query.iterate().next 7e,<$PH
#xWC(*Ggp
()).intValue(); $Cu/!GA4.>
return count; +n1jP<[<N
} ^iaeY
jI
vBUl6EmWu
/* (non-Javadoc) OtopA)
* @see com.adt.dao.UserDAO#getUserByPage ?nm:e.S+?
)p.+39]{2
(org.flyware.util.page.Page) >M` swEj
*/ Kd_WN;l
publicList getUserByPage(Page page)throws )G(6=l*
YK#
QH"}
HibernateException { #=WDJT:
String querySentence = "FROM user in class pv;c<NQ'1
gto@o\&=
com.adt.po.User"; dEXHd@"H
Query query = getSession().createQuery Pn{yk`6E
T;- Zl[H
(querySentence); "Y&+J@]
query.setFirstResult(page.getBeginIndex()) r#{r]q_E*
.setMaxResults(page.getEveryPage()); b0a'Y"oef4
return query.list(); T7;)HFGeW
} k&nhF9Y4
N0s)Nao4
} 9Ao0$|@b
ujcS>XN,1
Rl 4r 9
"X']_:F1a
<_*8a(j3
至此,一个完整的分页程序完成。前台的只需要调用 kO<`RHlX=
YYI
userManager.listUser(page)即可得到一个Page对象和结果集对象 =#XsY,r
>J=x";,D|~
的综合体,而传入的参数page对象则可以由前台传入,如果用 #( nheL
X$JO<@x
webwork,甚至可以直接在配置文件中指定。 {nQ}t
}B
1A23G$D
下面给出一个webwork调用示例: *D1fSu!
java代码: z(<
E %
f{e*R#+&
7YbI|~
/*Created on 2005-6-17*/ Q:+Y-&||"
package com.adt.action.user; </y V
D<7S
P,D
import java.util.List; OU=9fw
$52Te3n
import org.apache.commons.logging.Log; RCt)qh+
import org.apache.commons.logging.LogFactory; @"9y\1u
import org.flyware.util.page.Page; [Hdk=p
@{_PO{=\C
import com.adt.bo.Result; '4sT+q
import com.adt.service.UserService; m@JU).NKCS
import com.opensymphony.xwork.Action; mxHNK4/
v >3ctP{
/** rOY^w9!
* @author Joa <YL\E v/[
*/ kyJv,!};
publicclass ListUser implementsAction{ wrG*1+r
\Y9=dE}
privatestaticfinal Log logger = LogFactory.getLog Oe9{`~
d$r JW m5H
(ListUser.class); KHr8\qLH
1jmhh!,
private UserService userService; jTws0=F*
wri[#D {
private Page page; RA[` Cp"
!w
f N~.Y
privateList users; UO"8 I2rB
5d}PrYa
/* 7k6rhf7H
* (non-Javadoc) CjQ_oNI
* +:&(Ag
* @see com.opensymphony.xwork.Action#execute() NtTLvO6
*/ =mqV&FgRo
publicString execute()throwsException{ lO,
2
Result result = userService.listUser(page); z,rWj][P
page = result.getPage(); Cw{#(xX
users = result.getContent(); %o4d43uZ
return SUCCESS; C`mXEX5
} ^e>v{AE%
4v2(YJ%u
/** ( kp}mSw
* @return Returns the page. ZJ=C[s!wu
*/ EZP2Bb5g
public Page getPage(){ 0nie>
return page; (%0X\zvu/
} dc&Qi_W
BpP\C!:^
/** ;8
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* @return Returns the users. /LSiDys
*/ 66L*6O4
publicList getUsers(){ SgXXitg9+
return users; r.ajw&J2
} Y_/Kd7,\~
`MTOe1
/** '&<-,1^L
* @param page $E7yJ|p{
* The page to set. N_0&3PUSM
*/ [q.W!l4E
publicvoid setPage(Page page){ qE,%$0g
this.page = page; O1#rCFC|y
} q=nMZVVlF(
7DYD+N+T
/** h y[_
* @param users B8s|VI
* The users to set. Olxb`x
*/ =m/2)R{
publicvoid setUsers(List users){
P`bR;2o
this.users = users; L<QDC
} n@mUQ6
M3z7P.\G
/** ;?:,L
* @param userService >a4Bfnf"eI
* The userService to set. zV80r+y
*/ T@Q<oNU
publicvoid setUserService(UserService userService){ Rkm7"dO0
this.userService = userService; 19#)#
n^
} ]ipVN
} O_iX1@SW
Osy5|Ts
*<0g/AL
|d`?wm-
2! 6Kzq
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, y mE`V
VR:b1XWX
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 shn-Es*
+?@qux!
么只需要: v<c Hx/
java代码: 0~S<}N
mMjVbeh[
3o^V$N.
<?xml version="1.0"?> 57MoO
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork \U-5&,fP
&YMVoyVD
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
Y-{spTI
WI~%n
1.0.dtd"> VmT5?i
L+kS8D<
<xwork> a0LX<}
"Q
J-IRt&
<package name="user" extends="webwork- /6.b>|zF
JWdG?[$
interceptors"> /nmfp&@
mn4;$1~e>H
<!-- The default interceptor stack name ut,"[+J
0,3 ':Df
--> 7> ]C2!
<default-interceptor-ref HZ}'W<N
(Z5#;rgem
name="myDefaultWebStack"/> U D(#u3z
2bC%P})m
<action name="listUser" vSL{WT]m
CFA>
class="com.adt.action.user.ListUser"> bbM
!<&F
<param ~VGK#'X:
N|)V/no 6
name="page.everyPage">10</param> OlJj|?z$
<result ;7A,'y4f
+=8Po'E^!d
name="success">/user/user_list.jsp</result> &tOD
</action> `j$d(+Gv
!58JK f
</package> >dGYZfqD
\*
#4
</xwork> $g^;*>yr
{ULnQ6@
Dw[Q,SE
0Q9OQqg
m
TExlGAHo+O
E;Hjw0M'k
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 c 1GP3
;CZcY] ol
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。 `!8Z"xD
'W*F[U*&HP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5S?yj
463dLEd
}{y$$X<:
BSf"'0I&
u\wd<<I']
我写的一个用于分页的类,用了泛型了,hoho iE`aGoA
l :"*]m7o_
java代码: 7KIQ)E'kG|
&O,$l3 P
ZB%~>
package com.intokr.util; T1&H!
:JIPF=]fc
import java.util.List; *ZGN!0/
0}V'\=F454
/** do,X{\
* 用于分页的类<br> LfApVUm
* 可以用于传递查询的结果也可以用于传送查询的参数<br> DPx,qM#h5O
* J;`~
!g
* @version 0.01 A{%;Hd`0/
* @author cheng -`UlntEdZ:
*/ [
_$$P*
public class Paginator<E> { >xKRU5
privateint count = 0; // 总记录数 t@n (a
privateint p = 1; // 页编号 U'G`Q0n
privateint num = 20; // 每页的记录数 QEKFuY<E+
privateList<E> results = null; // 结果 bl<7[J.
z;fSd
/** .
6dT5x8u
* 结果总数 ^ym{DSx
*/ ^aCYh[=
publicint getCount(){ WRyLpTr-
return count; J.l%HU
} $H} Mn"G
Qknc.Z}
publicvoid setCount(int count){ X%CPz.G
this.count = count; L#Y;a
5b
} | hM)e*"
{SJ7Yfs
/** ?<QFW#:)
* 本结果所在的页码,从1开始 BaAb4{
* :nUsC+oBS
* @return Returns the pageNo. bicL%I2h
*/ JUFO.m^w
publicint getP(){ Q8oo5vqQ#C
return p; |plo65
} fZfiiE~7J
5qEdN
/** F`.7_D
* if(p<=0) p=1 oZ[ w
* 55b |zf
* @param p 2v1&%x:y#
*/ -Wk"o?}q
publicvoid setP(int p){ V2%wb\_z
if(p <= 0) qEr[fC@x
p = 1;
[i1D~rCcn
this.p = p; v6\2mc.
} #.YcIR)
vh8Kd' y
/** q"<-
* 每页记录数量 re J?38(
*/ 4>C=:w
publicint getNum(){ s'Gy+h.
return num; ix @rq#
} ZMg9Qt
kw ^ Sbxm
/** Qm x~_
* if(num<1) num=1 'a?.X _t
*/ K0=E4>z,`q
publicvoid setNum(int num){ WC*:\:mh
if(num < 1) D D;+& fe
num = 1; kGV`Q
this.num = num; t>@3RBEK
} =w$"wzc
TbAdTmW
/** aB6LAb2z;T
* 获得总页数 @M^QhHs
*/ G$9|aaf`1#
publicint getPageNum(){ @SG"t,5s
return(count - 1) / num + 1; jI<WzvhYG
} [Ms{J!^q
|P0L,R
/** {59VS
Nl
* 获得本页的开始编号,为 (p-1)*num+1 ixHZX<6zYT
*/ 9O T4jAm
publicint getStart(){ D)7$M]d%
return(p - 1) * num + 1; '!h0![OH
} `Mp7})
rIfGmh%H
/** IBNQmVRrI
* @return Returns the results. $RNUr
\9A
*/ SJc@iffS
publicList<E> getResults(){ (Cd{#j<
return results; z/&a\`DsU
} 8|qB1fB
6 %k+0\d
public void setResults(List<E> results){ SLjf<.S
this.results = results; RHl=$Hm.%
} bd
P,Zqd
n.XhK_6n]M
public String toString(){ UK_aqB
StringBuilder buff = new StringBuilder =<zSF\Zr_
bb/?02*)H
(); $EGRaps{j>
buff.append("{"); h k!,
buff.append("count:").append(count); BS,5W]ervE
buff.append(",p:").append(p); PWN'.HQ
buff.append(",nump:").append(num); ]F*a PV
buff.append(",results:").append XZdr`$z f
m":SE? {{&
(results); C| L^Ds0
buff.append("}"); 2
ssj(Qo
return buff.toString(); W
aGcoj
} 6+B{4OY
7kX$wQZ_
} ^g-t#O lD?
^*xHy`
Ds%&Mi