Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {;iG}j K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 n'dxa<F2|
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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 3I rmDT
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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 R0 g-
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分页支持类: W?*]'0
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java代码: [c{/0*
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package com.javaeye.common.util; ws{2 0
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import java.util.List; \xQ10\u
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publicclass PaginationSupport { /& qN yo
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publicfinalstaticint PAGESIZE = 30; |"7^9(
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privateint pageSize = PAGESIZE; 5CSihw/5
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privateList items; i2PPVT
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privateint totalCount; GsYi/Z
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privateint[] indexes = newint[0]; rUb`_ W@
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privateint startIndex = 0; {}vB#!
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public PaginationSupport(List items, int w(sD}YA)
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totalCount){ Nb))_+/
setPageSize(PAGESIZE); LI>tN R~
setTotalCount(totalCount); MZpG1
setItems(items); ERql^Yr
setStartIndex(0); qqm7p
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} U%swqle4
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public PaginationSupport(List items, int f}4bnu3
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totalCount, int startIndex){ 8=]R6[,fD
setPageSize(PAGESIZE); :r<uH6x|
setTotalCount(totalCount); zi^T?<t
setItems(items); l9U^[;D
setStartIndex(startIndex); )PM&x
} rPK)=[MZ
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public PaginationSupport(List items, int Ab]`*h\U
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totalCount, int pageSize, int startIndex){ 1LgzqRq
setPageSize(pageSize); ZfzUvN&!
setTotalCount(totalCount); l8"
setItems(items); i+I%]
setStartIndex(startIndex); LuM[*_8
} a88(,:t
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publicList getItems(){ -y8?"WB(b
return items; :R/szE*Ak
} 63ig!-9F
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publicvoid setItems(List items){ YTiXUOj
this.items = items; bt=%DMTn
} [LwmzmV+F
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publicint getPageSize(){ ,S|v>i,@
return pageSize; |Rh%wJ
} ] ~;x$Z)
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publicvoid setPageSize(int pageSize){ e 1W9Z $m
this.pageSize = pageSize; F_m[EB
} ])dq4\Bw
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publicint getTotalCount(){ =WaZy>n}7
return totalCount; ]fN\LY6p
}
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publicvoid setTotalCount(int totalCount){ 67/&AiS?
if(totalCount > 0){ <&n\)R4C1
this.totalCount = totalCount; ,a N8`M
int count = totalCount / ;&|MNN^
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pageSize; -Y#YwBy;M
if(totalCount % pageSize > 0) [4V{~`sF
count++; [25[c><:w"
indexes = newint[count]; }L.xt88
for(int i = 0; i < count; i++){ HPGMR4=ANS
indexes = pageSize * o%ZtE
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i; :iWW2fY
} PgNg1
}else{ &E0d{2
this.totalCount = 0; PZVh)6f"c
} C_SJ4Sh
} KrcL*j&^
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publicint[] getIndexes(){ W^}fAcQKH
return indexes; ZzU3j ^
} }9w?[hXW"
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publicvoid setIndexes(int[] indexes){ c/fU0cA@
this.indexes = indexes; 9,7IsT8
} dLV>FpA\
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publicint getStartIndex(){ w8!S;~xKI
return startIndex; :'*;>P
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} sdk%~RN0T
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publicvoid setStartIndex(int startIndex){ ![=C`O6K
if(totalCount <= 0) sW'SR
this.startIndex = 0; p 8,wr )
elseif(startIndex >= totalCount) 4Wz@^7|V5
this.startIndex = indexes xgw[)!g^\
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[indexes.length - 1]; q; &\77i$
elseif(startIndex < 0) FerQA9K)x
this.startIndex = 0; inO)Y]|f
else{ Nj8 `<Sl
this.startIndex = indexes gq[|>Rs75
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[startIndex / pageSize]; B d#D*"gx
} ~>h_#sIBC
} ,{"%-U#z
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publicint getNextIndex(){ >/,7j:X
int nextIndex = getStartIndex() + C&Nga
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pageSize; 8UH
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if(nextIndex >= totalCount) QU4/hS;Ux
return getStartIndex(); #G'Y2l
else qmNg Ez%
return nextIndex; ,(h:0L2v7d
} oD_n+95B
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publicint getPreviousIndex(){ )f#raXa5+
int previousIndex = getStartIndex() - blbL49;
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pageSize; AfU~k!4`
if(previousIndex < 0) drr
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return0; +;Yd<~!c Z
else y~,mIM$[@
return previousIndex; >LvQ&fAo
} 5](-(?k}~
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} G/l 28yt
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抽象业务类 3em&7QM
java代码: [1OX:O|
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/** l*~ ".q;S
* Created on 2005-7-12 M1{ru~Z9
*/ '@~\(SH
package com.javaeye.common.business; \Y37wy4
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import java.io.Serializable; woQ UrO(
import java.util.List; Ie12d@
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import org.hibernate.Criteria; lB7 V4
import org.hibernate.HibernateException; -&L(0?*qo
import org.hibernate.Session; F]_w~1
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import org.hibernate.criterion.DetachedCriteria; }6U`/"RfcO
import org.hibernate.criterion.Projections; oqLM-=0<}
import dRl*rP/
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org.springframework.orm.hibernate3.HibernateCallback; ^oykimYI-
import ~353x%e'
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org.springframework.orm.hibernate3.support.HibernateDaoS <xb =.xe
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upport; %E1_)^^
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import com.javaeye.common.util.PaginationSupport; }f/xMp-Y
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public abstract class AbstractManager extends h-0#h/u>M
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HibernateDaoSupport { xN^ngRg0
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privateboolean cacheQueries = false; Qyh_o
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privateString queryCacheRegion; d&N[\5q
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publicvoid setCacheQueries(boolean 3Ryae/Nk
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cacheQueries){ |.asg
this.cacheQueries = cacheQueries; #CRAQ#:45(
} V_1'` F
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publicvoid setQueryCacheRegion(String nnw5
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queryCacheRegion){ TGSUbBgU
this.queryCacheRegion = !YM;5vte+
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queryCacheRegion; \Z?.Po`!j
} at N%csA0
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publicvoid save(finalObject entity){ MLd*WpiI.
getHibernateTemplate().save(entity); ~~8?|@V
} [/P}1
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publicvoid persist(finalObject entity){ tTX@Bb8
getHibernateTemplate().save(entity); [,@gSb|D?
} r~<I5MZY
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publicvoid update(finalObject entity){ JDa=+\_
getHibernateTemplate().update(entity); |._9;T-Yde
} ;*~y4'{z
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publicvoid delete(finalObject entity){ GnCO{"n
getHibernateTemplate().delete(entity); ;usv/8
} LTof$4s
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publicObject load(finalClass entity, Oo)MxYPU
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finalSerializable id){ @i" ^b
return getHibernateTemplate().load t;>"V.F<1
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(entity, id); yf lt2 R
} 'N7AVj
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publicObject get(finalClass entity, Qz[4M` M
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finalSerializable id){ TgDx3U[
return getHibernateTemplate().get -pF3q2zb
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(entity, id); #]g9O ?0$
} Boi?Bt
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publicList findAll(finalClass entity){ @u4q\G\
return getHibernateTemplate().find("from \!]Zq#*kH
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" + entity.getName()); C>A*L4c]F
} JQ[~N-
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publicList findByNamedQuery(finalString .lcI"%>
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namedQuery){ kS\A_"bc
return getHibernateTemplate KRL9dD,&
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().findByNamedQuery(namedQuery); Y[\ZN
} {I]X-+D|_
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publicList findByNamedQuery(finalString query, QcXqMx
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finalObject parameter){ Sz"rp9x+
return getHibernateTemplate f0<'IgN
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().findByNamedQuery(query, parameter); qh40nqS;9
} L_k'r\L
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publicList findByNamedQuery(finalString query, G#|`Bjv"aP
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finalObject[] parameters){ 0-N"_1k|?
return getHibernateTemplate ;:^^Qfp
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().findByNamedQuery(query, parameters); CP%?,\
} bPe|/wp
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publicList find(finalString query){ cyQ&w>'
return getHibernateTemplate().find e1
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(query); 2a\?Q|1C
} ;q3"XLV(T[
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publicList find(finalString query, finalObject &4m\``//9
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parameter){ |z5`h
return getHibernateTemplate().find O.9r'n4f
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(query, parameter); U|NVDuo{{x
} X}Oo5SNgff
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public PaginationSupport findPageByCriteria R
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(final DetachedCriteria detachedCriteria){ (B0tgg^jj,
return findPageByCriteria 5y1:oiE/
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3~r>G
} {cYS0%Go
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public PaginationSupport findPageByCriteria 6oQSXB@
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(final DetachedCriteria detachedCriteria, finalint {p70(
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startIndex){ ) vKZs:
return findPageByCriteria Q;'{~! =
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(detachedCriteria, PaginationSupport.PAGESIZE, +ROwk
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startIndex); JIA'3"C
} 2,3pmb
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public PaginationSupport findPageByCriteria [ITtg?]F
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(final DetachedCriteria detachedCriteria, finalint +@j@# ~=K
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pageSize, y\xa<!:g
finalint startIndex){ v Mi&0$
return(PaginationSupport) w<0F-0:8
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getHibernateTemplate().execute(new HibernateCallback(){ H/v|H}d;
publicObject doInHibernate Ha}TdQ%
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(Session session)throws HibernateException { da,Bnze0
Criteria criteria = -k+}w_<Q
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detachedCriteria.getExecutableCriteria(session); a@ub%laL
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int totalCount = P`HDQ/^O
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((Integer) criteria.setProjection(Projections.rowCount ;ye5HlH}.
[s"e?Qee
()).uniqueResult()).intValue(); 9?IvSv}z
criteria.setProjection %:DH_0
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(null); E;m-^dxc
List items = }%@q; "9`
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criteria.setFirstResult(startIndex).setMaxResults t.ci!#/d
!qQB}sAf
(pageSize).list(); e[:i`J2
PaginationSupport ps = z+k[HE^S
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new PaginationSupport(items, totalCount, pageSize, x e!([^l&
z"vI-~,YU
startIndex); ZSUbPz
return ps; W{1"
} v95O)cC:W
}, true); /ZeN\ybx
} j-R9=vB2
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public List findAllByCriteria(final 1c%ee$Q
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DetachedCriteria detachedCriteria){ zIeJ[J@
return(List) getHibernateTemplate j$5S_]2
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().execute(new HibernateCallback(){ =Ay'\j
publicObject doInHibernate ]8c%)%Vi
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(Session session)throws HibernateException { 4^jIV!V
Criteria criteria = gpe/ dfyJ9
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detachedCriteria.getExecutableCriteria(session); )yj:P
return criteria.list(); fGz++;b<S
} :9O"?FE
}, true); `/4R$E{
} &>T7]])
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public int getCountByCriteria(final E;vF
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DetachedCriteria detachedCriteria){ +pefk+
Integer count = (Integer) Bc!ZHW*&
;
{ MK
getHibernateTemplate().execute(new HibernateCallback(){ WA$Ug
publicObject doInHibernate r) SG!;X
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(Session session)throws HibernateException { @}8~TbP
Criteria criteria = b;O@|HK&~
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detachedCriteria.getExecutableCriteria(session); B'kV.3t
return s;9>YV2at
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criteria.setProjection(Projections.rowCount w9W0j
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()).uniqueResult(); Ne=o+ $.(
} >cV^f6fH
}, true); ] C&AU[U*
return count.intValue(); !VXs
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} }nO[;2Na
} M#?^uu'
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用户在web层构造查询条件detachedCriteria,和可选的 ' thEZ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @8;0p
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PaginationSupport的实例ps。 \(.])I>)eh
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ps.getItems()得到已分页好的结果集 WbP
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ps.getIndexes()得到分页索引的数组 .R<Ke\y/
ps.getTotalCount()得到总结果数 R'Y=-
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ps.getStartIndex()当前分页索引 2GB+st,
ps.getNextIndex()下一页索引 Vo; B#lK
ps.getPreviousIndex()上一页索引 p`CVq `k
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 sgRD]SF
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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 { yvKUTq`
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一下代码重构了。 KkF3E*q\H
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我把原本我的做法也提供出来供大家讨论吧: fho$:S
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首先,为了实现分页查询,我封装了一个Page类: \`MX\OR
java代码: 1I1Z),
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/*Created on 2005-4-14*/ >@T(^=Q
package org.flyware.util.page; R DAihq
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/** R=/6bR57
* @author Joa L
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* 1,/L&_=_A
*/ +~H mPQ
publicclass Page { ' >F_y t9
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/** imply if the page has previous page */
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privateboolean hasPrePage; }$zJdf,\
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/** imply if the page has next page */ R06zca
privateboolean hasNextPage; R'.YE;leBG
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/** the number of every page */ VHUOI64*
privateint everyPage; 'h:[[D%H`
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/** the total page number */ 6$l6>A
privateint totalPage; 2Q/#.lNL
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/** the number of current page */ Ijs"KAW
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privateint currentPage; u3Jsu=Nx-
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/** the begin index of the records by the current bN',-[E
.).*6{_
query */ `c-(1;Jb
privateint beginIndex; ~5f|L(ODX
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/** The default constructor */ \qU .?V[2
public Page(){ =h"*1`
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} IIW6;jS
1 ^k#g,
/** construct the page by everyPage ;h
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* @param everyPage dF-d
* */ wW1E
'Vy{
public Page(int everyPage){ e+ZC<Bdh
this.everyPage = everyPage; -bq\2Yc$]
} g@ ZZcBx
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/** The whole constructor */ 1HBdIWhHv.
public Page(boolean hasPrePage, boolean hasNextPage, xzGs%01]
@+S5"W
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int everyPage, int totalPage, 9%VNzPzf
int currentPage, int beginIndex){ kp+\3z_
this.hasPrePage = hasPrePage; D-zqu~f`
this.hasNextPage = hasNextPage; n,Z B-"dW
this.everyPage = everyPage; <AzM~]"3
this.totalPage = totalPage; 9bpY>ze
this.currentPage = currentPage; 7;_./c_@
this.beginIndex = beginIndex; "I|[m%\
} I&}Md73
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/** kdWk{ZT^
* @return x{B%TM-Ey
* Returns the beginIndex. ">? y\#OA
*/ -9 AI@^q
publicint getBeginIndex(){ #hBDOXHPf
return beginIndex; qP"<vZ
} *+E9@r=HF
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/** sf|[oD
* @param beginIndex TV>UD
q
* The beginIndex to set. 8^H <dR
*/ *(~=L%s
publicvoid setBeginIndex(int beginIndex){ uQ;b'6Jcp
this.beginIndex = beginIndex; <3!jra,h
} )32BM+f"77
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/** hb>,\46}
* @return d.7pc
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* Returns the currentPage. |<@X* #X5
*/ ZW}0{8Dk
publicint getCurrentPage(){ Vm1U00lM{
return currentPage; 4g.y$
} :EK.&%2
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/** 07T"alXf:A
* @param currentPage &oWdBna"_
* The currentPage to set. &&}'
*/ ACg5"
publicvoid setCurrentPage(int currentPage){ T[iwP~l
this.currentPage = currentPage; |zV-a2K%J
} 3
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/** 'w+T vOB
* @return RhG9Xw9
* Returns the everyPage. %} _{_Z
*/ Os?`!1-
publicint getEveryPage(){ r lalr+Rf
return everyPage; HNA/LJl[VU
} ,qgph^C
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/** Ld[zOx
* @param everyPage zkdyfl5
* The everyPage to set. iBy:HH
*/ 4Lx#5}P
publicvoid setEveryPage(int everyPage){ `N~;X~XFk
this.everyPage = everyPage; npH2&6Yhi^
} uvK1gJrA)
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/** |wKC9 O@%
* @return CQo<}}-o
* Returns the hasNextPage. r^?Q o
*/ RZ!-,|"cwL
publicboolean getHasNextPage(){ sskwJu1
return hasNextPage; (Ck|RojC
} o;XzJ#P
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/** 9PA\Eo|Yb
* @param hasNextPage F/\w4T
* The hasNextPage to set. b!Q|0X.?
*/ a _YE[6
publicvoid setHasNextPage(boolean hasNextPage){ M@rknq@
this.hasNextPage = hasNextPage; +'$=\d^
} C@` eYi
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/** ZZf-c5 g
* @return :7t~p&J
* Returns the hasPrePage. ?|8H|LBIr
*/ M`$s
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publicboolean getHasPrePage(){ }fW@8ji\
return hasPrePage; P1b5=/}:V
} vMsb@@O\ \
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/** (
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* @param hasPrePage O|J`M2r
* The hasPrePage to set. m}] bP
*/ @Y'BqDFlZ
publicvoid setHasPrePage(boolean hasPrePage){ DUc
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this.hasPrePage = hasPrePage; }g:y!pk
} [XWY-q#Gg
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/** Lrgv:n
* @return Returns the totalPage. j4L )D
* f%0^89)
*/ "VxZnT
publicint getTotalPage(){ vgSs]g
return totalPage; Kd8V,teH
} R9o3T)9V
#EiOC.A=
/** C2;qSKG3{m
* @param totalPage A.<HOx
* The totalPage to set. 4oT1<n`r+
*/ PW"G]G,
publicvoid setTotalPage(int totalPage){ V-U,3=C
this.totalPage = totalPage; >OVi{NyT
} w#wlZ1f
N\ ?%944R
} Z
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6LRI~*F=3
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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 EOu\7;kE9
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个PageUtil,负责对Page对象进行构造: L;=:OX0
java代码: & IVwm"
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/*Created on 2005-4-14*/ ]q DhGt
package org.flyware.util.page; [6Y6{.%~
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import org.apache.commons.logging.Log; zXQo pQ1
import org.apache.commons.logging.LogFactory; mw9;LNi\D
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/** OJn g
* @author Joa sZ #Ck"n
* 6/@"K
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*/ ZcgSVMqEX
publicclass PageUtil { A-e#&pJ
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privatestaticfinal Log logger = LogFactory.getLog Ml)~%ZbF
'awL!P--
(PageUtil.class); /w0l7N
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/** w4U]lg<}E
* Use the origin page to create a new page w}VS mt$F
* @param page R4G$!6Ld
* @param totalRecords 'NF_!D
* @return Z,/BPK<e
*/ u1a5Vtel
publicstatic Page createPage(Page page, int rMIr&T
,@ A1eX}
totalRecords){ sXp>4MomV
return createPage(page.getEveryPage(), #9 5.KkF
h(!x&kZq.
page.getCurrentPage(), totalRecords); 1UX"iOx(
} 59gt#1k
jPg 8>Z&D
/** EzOO6
* the basic page utils not including exception 2@ vSe
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handler ;u!qu$O
* @param everyPage aObWd5~
* @param currentPage ]YQ[ )
* @param totalRecords >=-w2&
* @return page vwDnz/-
*/ k`Nc<nN8
publicstatic Page createPage(int everyPage, int l`8S1~j
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currentPage, int totalRecords){ ?ihkV?;)
everyPage = getEveryPage(everyPage); 'L)@tkklp
currentPage = getCurrentPage(currentPage); pASNiH698
int beginIndex = getBeginIndex(everyPage, VH7VJ [
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currentPage); iLw O4i
int totalPage = getTotalPage(everyPage, wvsKnYKX
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totalRecords); Cw]&B
boolean hasNextPage = hasNextPage(currentPage, {LfVV5?
4VINu9\V
totalPage); mw)KyU#l,:
boolean hasPrePage = hasPrePage(currentPage); F2!C^r,~L
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returnnew Page(hasPrePage, hasNextPage, IBWUXG;
everyPage, totalPage, s 7re
currentPage, ^Ts|/+}'i
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beginIndex); uc9t0]o=h
} An cmSi
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privatestaticint getEveryPage(int everyPage){ &1Dq3%$c
return everyPage == 0 ? 10 : everyPage; @ qWgokf
} r#
MJ
tr0P;}=
privatestaticint getCurrentPage(int currentPage){ {vh}f+2
return currentPage == 0 ? 1 : currentPage; $}&Y$w>S
} ]2\|<.
_]8FCO
privatestaticint getBeginIndex(int everyPage, int j#d=V@=a
WGFp<R
currentPage){ {pMbkAQ@
return(currentPage - 1) * everyPage; hI*gw3V
} @~%R%Vu
9,\b$?9
privatestaticint getTotalPage(int everyPage, int s*{l}~fPkW
aP^,@RrL
totalRecords){ i:W.,w%8
int totalPage = 0; [2I1W1pd
Xdj` $/RI
if(totalRecords % everyPage == 0) >2tQ')%DJ
totalPage = totalRecords / everyPage; '"&M4.J{
else q eLfO
totalPage = totalRecords / everyPage + 1 ; Q!8AFLff4
\}Fx''
return totalPage; U 2am1}
} @qk$
6X
<?'d\B
privatestaticboolean hasPrePage(int currentPage){ O?e38(
return currentPage == 1 ? false : true; %LeG.~?
} $,$bZV
K|nh`r
privatestaticboolean hasNextPage(int currentPage, 7YT%.ID
]w z`j1
int totalPage){ h`n,:Y^++P
return currentPage == totalPage || totalPage == >+y[HTf-
rZ`ob x\S
0 ? false : true; 9r.Os
} N"SFVc_2
|}N -5U
Zg1=g_xY
} qYFOHu
0dxEV]
dPplZ,Y%
U@21N3_@_
SyFw
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。 yJ*`OU#
21'I-j
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 tE3#Uq
^`>,~$Q
做法如下: /f_w@TR\{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~t7?5b?*\
`|?K4<5|
的信息,和一个结果集List: )90 Q
java代码: 3)\jUVuj
U;QTA8|!&
wSoIU,I
/*Created on 2005-6-13*/ o1C1F}gxU
package com.adt.bo; QND{3Q
5(RFkZn4[
import java.util.List; jMv qKJ(<
-|;{/ s5
import org.flyware.util.page.Page; -xs@rV`
q5C(/@)^
/** 0Oy.&C T
* @author Joa |Iei!jm
*/ x=>B 6o-f
publicclass Result { qv\n]M_&
Er/h:=
private Page page; B].V|8h
nmIos]B
private List content; buV{O[
UhKC:<%
/** xgoG>~F
* The default constructor | 4/'~cYV
*/ !9A6DWA E$
public Result(){ `-@8IZ7
super(); -PX Rd)~
} {*utke]}*
n
N.6?a
/** BUcPMF%\y:
* The constructor using fields .*\TG/x
* .Z%y16)T
* @param page eC`} oEz
* @param content |f5WN&c
*/ 4WCWu}
public Result(Page page, List content){ dH:z_$Mg
this.page = page; yOR]r+8
this.content = content; b(^/WCykH
} W^j;"qj
Mttt]]
/** 7A:k
* @return Returns the content. Do1 Ip&X
*/ .\Gl)W
publicList getContent(){ g7\MFertR^
return content; |v,%!ps
} 9N1Uv,OtB
{A!1s;
/** -u)f@e
* @return Returns the page. =' %r"_`}
*/ \j
C[|LM&
public Page getPage(){ ]q!,onJ
return page; ogD 8qrZ6J
} dH]0(aJ
Z;M}.'BE
/** FuqMT`
* @param content {qxFRi#\k
* The content to set. WX.6|
*/ QuFzj`(
public void setContent(List content){ akR+QZ,)
this.content = content; o[=h=&@5p
} |,YyuCQcL[
6.#5Ra
/** B%y?+4;zA
* @param page pXn(#n<
* The page to set. %[3?vX
*/ HC1jN8WDY
publicvoid setPage(Page page){ Ot,_=PP
this.page = page; R=Qa54
} nsf.wHGZ"J
} 4pU|BL\j
:+?eF^5
m@(8-_
|#OMrP+oi
sA^_I6>M"
2. 编写业务逻辑接口,并实现它(UserManager, j&6O1
{7EnM1]
UserManagerImpl) wY$'KmNW
java代码: T2EQQFs
Pv-El+e!
[\i0@
/*Created on 2005-7-15*/ S"-q*!AhK
package com.adt.service; D1xIRyc/
k@}?!V*l
import net.sf.hibernate.HibernateException; C1V:_-
(i3V[H
import org.flyware.util.page.Page; gc5u@(P"
;Gf,I1d}{
import com.adt.bo.Result; <V`1?9c7D1
sY|by\-c
/** aC!e#(q
* @author Joa BH`%3Mw
*/ 4k$i:st;
publicinterface UserManager { ;dC>$_P?
0cGO*G2Xr
public Result listUser(Page page)throws b\{34z,
=`&7pYd,
HibernateException; :A,g :B
LgG7|\(-
} mZ%"""X\Ei
4O I''i
2Ra}&ie
R=7,F6.
nky%Eb[\
java代码: 8%+F.r
3bWYRW
B|fh 4FNy
/*Created on 2005-7-15*/ /5**2Kgv1
package com.adt.service.impl; J&hzr t
a9f!f %9
import java.util.List; M53{e;.kN
w(,K
import net.sf.hibernate.HibernateException; 'R-Ly^:Qd
UrC>n
import org.flyware.util.page.Page; 1\t# *N
import org.flyware.util.page.PageUtil; /JcfAY
~8oti4
import com.adt.bo.Result; 8D
H~~by
import com.adt.dao.UserDAO; y3Z\ Y[
import com.adt.exception.ObjectNotFoundException; -(oFO'Lbg
import com.adt.service.UserManager; 6np
rT#2'-f
/** L- '{
* @author Joa k vuSE
*/ pqT+lai)#
publicclass UserManagerImpl implements UserManager { ]3 KMFV}
ce&Q}_
private UserDAO userDAO; xr*%:TwCta
CjQ)Bu*4
/** YK{E=<:
* @param userDAO The userDAO to set. l-v(~u7
*/ (GCe D-
publicvoid setUserDAO(UserDAO userDAO){ e>zv+9'Q
this.userDAO = userDAO;
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} Z&Qz"V>$
TA9Kg=_
/* (non-Javadoc) w'r?)WW$
* @see com.adt.service.UserManager#listUser av8\?xmo.$
^ ,cwm:B@
(org.flyware.util.page.Page) H{d;,KfX
*/ vvi[+$M
public Result listUser(Page page)throws @$*LU:[
Y3 V9
HibernateException, ObjectNotFoundException { ZFxa2J~ ;
int totalRecords = userDAO.getUserCount(); 7{BTtUMAC
if(totalRecords == 0) &^7^7:Y=?
throw new ObjectNotFoundException :lfUVa{HN
j@o
\d%.'!
("userNotExist"); lSG"c+iV
page = PageUtil.createPage(page, totalRecords); \jpm
List users = userDAO.getUserByPage(page); W5SCm(QS5
returnnew Result(page, users); vyA
`Z1
} hI#1Ybl
W2`/z)[*>
} yKhN1kY
/cXVJ(#j
)IFFtU~,
au;ZAXM|
f(*ygI
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2?}5U)Hg
\RF{ITV$kD
询,接下来编写UserDAO的代码: LkwjEJQf
3. UserDAO 和 UserDAOImpl: sX
c|++
java代码: h>:eu#
+7V4mF!u
}o:sU^Pwa
/*Created on 2005-7-15*/ }\?]uNH
package com.adt.dao; 2R`dyg
?= RC?K
import java.util.List; vU9j|z
MXP3ZN'
import org.flyware.util.page.Page; +
FG Xx
JFOXrRR=d
import net.sf.hibernate.HibernateException; -tH ^Deo
GF/!@N
/** i.5?b/l0
* @author Joa 8q/3}AnI
*/ S)\Yc=~h
publicinterface UserDAO extends BaseDAO { L#~z#
w|G4c^KH
publicList getUserByName(String name)throws \1MMz Z4rf
8h '~*
HibernateException; z#u<]] 5
N ]|P||fC
publicint getUserCount()throws HibernateException; AM:lU
*=)kR7,]9d
publicList getUserByPage(Page page)throws >g+e`!;6
2)F~
HibernateException; w7e+~8|
*%aWGAu:
} Z[GeU>?P
5<77o|
KM9)
$gPR3*0
9NEL[J|
java代码: 40m>~I^q}
-RBH5+SS2
vwIP8z~<
/*Created on 2005-7-15*/ +\s&v!
package com.adt.dao.impl; cKe{ ]a
ZD#{h J-
import java.util.List; E5. @=U,c
tg"NWp6
import org.flyware.util.page.Page; G|+naZ
B4RP~^
import net.sf.hibernate.HibernateException; /DxeG'O
import net.sf.hibernate.Query; ;a9`z+ K
;NPbEPL[5
import com.adt.dao.UserDAO;
) k6O
vD91t/_+
/** Z~Vups#+f
* @author Joa 8-geBlCE,
*/ \wb0%>
0
public class UserDAOImpl extends BaseDAOHibernateImpl /s[D[:P_
1MYA/l$
implements UserDAO { TO]7 %aB
9~|hGo
/* (non-Javadoc) PCX X[N
* @see com.adt.dao.UserDAO#getUserByName =67tQx58
E,gpi
(java.lang.String) Bxf]Lu,\U@
*/ v[!ZRwk4w3
publicList getUserByName(String name)throws Xo/0lT
'FC#O%l
HibernateException { Q$:>yveR*
String querySentence = "FROM user in class lEr_4!h$rZ
hMQh?sF/
com.adt.po.User WHERE user.name=:name"; D"ecwx{%;C
Query query = getSession().createQuery @mm~i~~KA
:&\^r=D
(querySentence); Xd@_:ds
query.setParameter("name", name); "LkI '>3}
return query.list(); 0`~#H1TK
} b3^d!#KVM
)D8V;g(7F
/* (non-Javadoc) <wj}y0(
* @see com.adt.dao.UserDAO#getUserCount() QQW]j;'~
*/ 2E_d$nsJ
publicint getUserCount()throws HibernateException { ~`!{5:v
int count = 0; }:xj%?ki
String querySentence = "SELECT count(*) FROM x2$Y"b?vz
MgrJ ;?L
user in class com.adt.po.User"; 4)z*Vux
Query query = getSession().createQuery 5169E*
;Sw%t(@
(querySentence); r NT>{
count = ((Integer)query.iterate().next a8v9j3.
K;P<c,9X/
()).intValue(); N*6lyFcg
return count; Y:KIaYkk
} %C=?Xhnv
/PTk296@
/* (non-Javadoc) .yN.
* @see com.adt.dao.UserDAO#getUserByPage Xb\de_8!
[l:}#5\]4
(org.flyware.util.page.Page) n"|1A..^
*/ vfpK|=[7o
publicList getUserByPage(Page page)throws
y8/+kn +
g>;u} +lO
HibernateException { Nny#}k
Bt
String querySentence = "FROM user in class =b/:rSd$NA
&!0%"4
com.adt.po.User"; ZK$<"z6{
Query query = getSession().createQuery "Wn8}T*
)I(2t 6i
(querySentence); &p83X
query.setFirstResult(page.getBeginIndex()) w[hT,$n
.setMaxResults(page.getEveryPage()); OTV$8{
return query.list(); !6pE0(V^+4
} L`n Ma
bY!1t}ALh
} k:*(..!0z
iVAAGZ>am
GQ])y
1<$z-y'
lm\~_ 4l1
至此,一个完整的分页程序完成。前台的只需要调用 j=y{ey7Fd
dvPlKLp
userManager.listUser(page)即可得到一个Page对象和结果集对象 h-6zQs
]^BgSC
的综合体,而传入的参数page对象则可以由前台传入,如果用 &N|`Q(QXS
qg9VK'3o
webwork,甚至可以直接在配置文件中指定。 0o_wy1O1,
-_+,HyJP
下面给出一个webwork调用示例: O]%Vh
l
java代码: j5~nLo2
apw/nhQ.[
|]+PDc%
/*Created on 2005-6-17*/ ^J?y
mo$>0
package com.adt.action.user; [a!*m<
z!>ml3
import java.util.List; Rr"D)|Y;C(
*z6m644H
import org.apache.commons.logging.Log; 1vUW$)?X
import org.apache.commons.logging.LogFactory; =+"=|cQ
import org.flyware.util.page.Page; K3-Cuku
8XhGo2zf
import com.adt.bo.Result; y_}jf,b4
import com.adt.service.UserService; Gf\u%S!%
import com.opensymphony.xwork.Action; 8}>s{u;W
94b*
!Z
/** {~{</ g/
* @author Joa C)R#Om
*/ &T2qi'
publicclass ListUser implementsAction{ 6:3F,!J!
;'P<#hM[$
privatestaticfinal Log logger = LogFactory.getLog a`_w9r+v
d 8%sGH
(ListUser.class); qfa[KD)!aB
o7 1f<&1
private UserService userService; M TOZ:b
H`EsFKw\%
private Page page; hYY-Eq4TC
U8GvUysB!
privateList users; !7y:|k,ac
k\A[p\
/* X].Igb)2
* (non-Javadoc) 7kq6VS;p
* [&K"OQ^\2h
* @see com.opensymphony.xwork.Action#execute() N={0A
*/ ZP;WXB`
publicString execute()throwsException{ t^SND{[WcM
Result result = userService.listUser(page); gQ=l\/H
page = result.getPage(); `~+[pY1r
users = result.getContent(); w
.+B h
return SUCCESS; |jJ9dTD8/
} ?
H7?>ZE
sQgJ`+Y8_
/** dO|n[/qL0
* @return Returns the page. |nT+W|0U
*/ #1<Jwt+
public Page getPage(){ ;`:A(yN]T
return page; tq&CJvJ4
} A_}6J,*u
0S$6j-"
/** '/
*;g#W=
* @return Returns the users. cByUP#hW
*/ |7@@~|A
publicList getUsers(){ *D:uFo,xn
return users; *@zya9y9q
} X-}]?OOs
@D7/u88|
/** :<i<\TH'
* @param page }-2U,Xg[
* The page to set. [s&0O<Wv
*/ k btQ
publicvoid setPage(Page page){ )F65sV{
this.page = page; jzAXC^FS
} eg(1kDMpn
MKZq*
/** >o|.0aw<
* @param users 3R6=C~
* The users to set. I|R;)[;X
*/ ( Qj;B)
publicvoid setUsers(List users){ 4d;.p1ro
this.users = users; $
nHf0.V1
} [kL`'yi
!G~`5?CvE
/** #kRt\Fzq
* @param userService 7O\ Qxc\
* The userService to set. f/UIpswrZ'
*/ F@rx/3
[
publicvoid setUserService(UserService userService){ $J!WuOz4^i
this.userService = userService; lOu&4Kq{g
} -mqL[ h,
} W~d^ *LZt
3fdqFJ O
!]2`dp\!
9Z
lfY1=
$3yn-'o'A
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, eh}I?:(a?
cs7K^D;.V
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 G}#p4\/
/[,0,B9!3
么只需要: pv@w 8*
java代码: k4`(7Z
,FWsgqL{l
a&%v ^r[
<?xml version="1.0"?> /f]'_t0\.
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ) 8 %lZ{
'QQa :3<x
1.0//EN" "http://www.opensymphony.com/xwork/xwork- uQO\vRh0
}Wz[ox 9b
1.0.dtd"> =H/ 5
@Jc^ur
<xwork> AGK{t+`
Z:.*fs5
<package name="user" extends="webwork- \fJ _,
]!v\whZ>
interceptors"> E3QyiW
d~z%kl
5:
<!-- The default interceptor stack name Hd?#^X
-$ha@bCWO
--> )| 0(#R
<default-interceptor-ref 21 N!?DR
:YM1p&|fS
name="myDefaultWebStack"/> "P8(R
OTD<3Q
q
<action name="listUser" #y*p7~|@
5m9;'SF
class="com.adt.action.user.ListUser"> 3h**y
%^
<param g-DFcwO,V
[1g
name="page.everyPage">10</param> 2}U:6w
<result rH9[x8e
Z=zD~ka
name="success">/user/user_list.jsp</result> ~$]Puv1V>
</action> Q&8epO |J
5;X3{$y
</package> qv)%)n
g
[c^7
</xwork> |C}= 1
8RjFp2)W
a3C\?5
*nlDN4Y[
Yge}P:d9
8B7~Nq'
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 XU6SYC"t%~
/5m ~t.Z9M
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。 ]BaK8mPl
|SuN3B4e
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 l09SWug
<~n%=^knE
M s Q=1
BjV;/<bt
uQiW{Kja2
我写的一个用于分页的类,用了泛型了,hoho R/jHH{T3
pP^5y{
java代码: Y3bZ&G)
Y{ OnW98
Tzr'3m_
package com.intokr.util; :&BE-f
F5%IsAH
import java.util.List; AYv7-!Yk
Ypwn@?xeP
/** 5E0dX3-
* 用于分页的类<br> ?b x ak
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >;+q,U}
* ]
D+'Ao^'
* @version 0.01 ?6 //'bO:%
* @author cheng a\tv,Lx
*/ E^? 3P'%^
public class Paginator<E> { t(Gg
1
privateint count = 0; // 总记录数 n..R'vNj
privateint p = 1; // 页编号 !'*1;OQ
privateint num = 20; // 每页的记录数 3Uy(d,N
privateList<E> results = null; // 结果 z?
Ck9
7',WLuD
/** . H9a
* 结果总数 b}J,&eYD
*/ 4%5 +
publicint getCount(){ k;Ask#rs
return count; rT';7>{g
} {ZKXT8'
c|Fu6LF a
publicvoid setCount(int count){ ?u~?:a@K
this.count = count; @P/6NMjZ^
} FY"csZ
TV~S#yg+H
/** 91M5F$
* 本结果所在的页码,从1开始 ]}L tf,9
* Ao$|`Lgj=z
* @return Returns the pageNo. (w-@b70E
*/ [ps5
publicint getP(){ ?wREX[Tqs
return p; 5G l:jRu
} 30{WGc@l#
~2[mZias
/** :(#5%6F
* if(p<=0) p=1 B}^l'p_u
* Z4369
* @param p 2X6L'!=
*/ nx@,oC4
publicvoid setP(int p){ LN`Y`G|op
if(p <= 0) USzO):o
p = 1; oW3|b2D
this.p = p; m-lTXA(
} <v3pI!)x
@.} @K
/** m.Ki4NUm
* 每页记录数量 lQ#='Jqfp
*/ !7Nz_d~n
publicint getNum(){ W|\$}@>
return num; Ca
?d8
} FTWjIa/[
Kon|TeC>d
/** /&W~:F
* if(num<1) num=1 |"YE_aYu
*/ \{;3'<
publicvoid setNum(int num){ Q-Oj%w4e
if(num < 1) [wn!
<#~v
num = 1; C sCH :>
this.num = num; mb*|$ysPx
} uMX\Y;N
7'Gkip
/** Y{9xF8#
* 获得总页数 }70A>JBw
*/ tv%B=E!r
publicint getPageNum(){ #3_
@aq*
return(count - 1) / num + 1; d[oHjWk
} f7:}t+d
;lf $)3%[
/** lPw`KW
* 获得本页的开始编号,为 (p-1)*num+1 k(M(]y_
*/ @4=Az1W*
publicint getStart(){ {!^0j{T
return(p - 1) * num + 1; *M'/z=V?%
} dP=,<H#]m
V#X<Yt
/** >DR$}{IV
* @return Returns the results. WJy\{YAG
*/ j[Gg[7q{y
publicList<E> getResults(){ | z?c>.
return results; fT{%zJU
} a(lmm@;V<
X=V2^zrt
public void setResults(List<E> results){ 8=OpX,t(
this.results = results; rUZ09>nDy
} +h8`8k'}-2
!Y10UmMu
public String toString(){ ]Rj?OSok
StringBuilder buff = new StringBuilder \k5
sdHmI[
h}Lrp r2r
(); GK1oS
buff.append("{"); 395`Wkv
buff.append("count:").append(count); Q096M 0m
buff.append(",p:").append(p); h!?rk|
buff.append(",nump:").append(num); wK0],,RN,h
buff.append(",results:").append ~>XqR/v
NRazI_Z
(results); (Ta (Y=!uq
buff.append("}"); Wpc8T="q
return buff.toString(); %:Z_~7ZR
} yw >Frb5p
Ho1 V)T>
} ANTWWs}
7m8(8$-6
eVj7%9