Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 jkNZv. )p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mId{f
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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 \Mlj
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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 tazBZ'\c
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分页支持类: d1j v>tu
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java代码: B>47Ic
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package com.javaeye.common.util; &TbnZnv
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import java.util.List; &F#X0h/m=
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publicclass PaginationSupport { I{cn ,,8
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publicfinalstaticint PAGESIZE = 30; of& vQ
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privateint pageSize = PAGESIZE; y i@61XI
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privateList items; v2@M,xbxF:
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privateint totalCount; udc9$uO
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privateint[] indexes = newint[0]; 0/K NXz
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privateint startIndex = 0; !#iP)"O
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public PaginationSupport(List items, int w#b~R^U
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totalCount){ # |UrHK;
setPageSize(PAGESIZE); 3!$rp- !<)
setTotalCount(totalCount); 0XozYyq
setItems(items); 3\@6i'
setStartIndex(0); [1vrv(u>
} NM]6 o
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public PaginationSupport(List items, int _ve7Is`/
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totalCount, int startIndex){ sox90o 7
setPageSize(PAGESIZE); F37,u|
setTotalCount(totalCount); <I|ryPU9{X
setItems(items); hG;u8|uT^i
setStartIndex(startIndex); V
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} -=qmYf
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public PaginationSupport(List items, int Yp
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totalCount, int pageSize, int startIndex){ H{GbOI.
setPageSize(pageSize); \|&5eeE@
setTotalCount(totalCount); )O&$-4gL'
setItems(items); U&eLj"XZ
setStartIndex(startIndex); Ns9g>~
} MoFZ
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publicList getItems(){ pI^n("|
return items; WD)[Ac[
} Ql V:8:H$
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publicvoid setItems(List items){ d~_OWCg`
this.items = items; l/I W"A
} z`_N|iEd
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publicint getPageSize(){ FP\[7?ZLn
return pageSize; (^Ln|3iz
} -zTeIvcy5
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publicvoid setPageSize(int pageSize){ >ab=LDoM
this.pageSize = pageSize; =Tj0dfO|"
} n_+Iw,a'm
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publicint getTotalCount(){ (HJ60Hj
return totalCount; eX$Biv1N
} Sn+Yi
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publicvoid setTotalCount(int totalCount){ Z3/ zUtgs
if(totalCount > 0){ HYY|)Wo
this.totalCount = totalCount; [p(C:rH
int count = totalCount / ;}PL/L$L6;
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pageSize; TUUBC%
if(totalCount % pageSize > 0) RcE%?2lD
count++; ~>EVI=?
indexes = newint[count]; >]`x~cE.5
for(int i = 0; i < count; i++){ OL=b hZ
indexes = pageSize * BxG;vS3>*e
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i; K4tX4U[Z
} U9q*zP_jV
}else{ c*W$wr
this.totalCount = 0; .KD07
} YJ0[BcZ
} [+1
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publicint[] getIndexes(){ R3<+z
return indexes; $200?[
} Yl f4q/-
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publicvoid setIndexes(int[] indexes){ f0uiNy(r$
this.indexes = indexes; ^m7PXY
} M1i|qjb:l
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publicint getStartIndex(){ -/</7I
return startIndex; ^Ve^}|qPc
} v$c D!`+k
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publicvoid setStartIndex(int startIndex){ 3m^BYr*y^
if(totalCount <= 0) 'ZDclz9}
this.startIndex = 0; Gg+>_b{S5T
elseif(startIndex >= totalCount) tEUmED0FY
this.startIndex = indexes VuY.})+J:
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[indexes.length - 1]; ev3x*}d0
elseif(startIndex < 0) wfdFGoy(
this.startIndex = 0; F~Li.qF
else{ We ->d |=
this.startIndex = indexes oK>,MdB
p#kC#{<nE
[startIndex / pageSize]; s5pY)6)
} TQou.'+v
} 2*M*<p=v
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publicint getNextIndex(){ r~TT c)2
int nextIndex = getStartIndex() + MXy{]o_H~
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pageSize; (gZ!o_
if(nextIndex >= totalCount) !2Orklzd1
return getStartIndex(); /F_
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else JVkawkeX
return nextIndex; sa` Yan
} S|[UEU3FpB
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publicint getPreviousIndex(){ g{%';
int previousIndex = getStartIndex() - UyQn onS
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pageSize; 'GFzI:Xr
if(previousIndex < 0) ]VvJ1Xn0
return0; 1@WGbORc*
else 82X.
return previousIndex; ^Toi_
} R+K[/AA
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} ^6+x0[13
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抽象业务类 %gaKnT(|r
java代码: QP#Wfk(C
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/** BGX@n#:
* Created on 2005-7-12 }]I?vyQ#V
*/ $<v_Vm?6d
package com.javaeye.common.business; K288&D|1WU
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import java.io.Serializable; sYXS#;|M
import java.util.List; e@OA>
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import org.hibernate.Criteria; 'T[zh#v>S
import org.hibernate.HibernateException; kgz{m;R
import org.hibernate.Session; sD8S2
import org.hibernate.criterion.DetachedCriteria; ]lUu%<-;
import org.hibernate.criterion.Projections; o(P:f)B
import RY{tX`
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org.springframework.orm.hibernate3.HibernateCallback; x/=j$oA
import j;)6uia*A
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org.springframework.orm.hibernate3.support.HibernateDaoS /<0D
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upport;
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import com.javaeye.common.util.PaginationSupport; (5~C
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public abstract class AbstractManager extends 9#<Og>t2y
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HibernateDaoSupport { j;)g+9`
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privateboolean cacheQueries = false; 0?SLRz8
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privateString queryCacheRegion; d 4]%Wdvf
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publicvoid setCacheQueries(boolean H|UL5<:]D
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cacheQueries){ >Mw &Tw}o
this.cacheQueries = cacheQueries; #ja`+w}
} P0xLx
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publicvoid setQueryCacheRegion(String SbZt\a 8
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queryCacheRegion){ U*Qq5=dqD
this.queryCacheRegion = 'c&@~O;^d
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queryCacheRegion; -kbm$~P
} 5vft}f
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publicvoid save(finalObject entity){ pm]DxJ@
getHibernateTemplate().save(entity); .KucjRI
} LUck>l\l
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publicvoid persist(finalObject entity){ Z=@)
getHibernateTemplate().save(entity); Jwd&[
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} d&uTiH? 0
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publicvoid update(finalObject entity){ .dT;T%3fO
getHibernateTemplate().update(entity); xGfDz*t
} 87KrSZ
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publicvoid delete(finalObject entity){ Cc)P5\jh
getHibernateTemplate().delete(entity); *O>aqu
} ]<gCq/V #
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publicObject load(finalClass entity, ]TgP!M&q
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finalSerializable id){ _AYC|R|
return getHibernateTemplate().load EWIc|b:
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(entity, id); ;#s}b1
} liqR#<
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publicObject get(finalClass entity, lVdT^"~3
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finalSerializable id){ zN+*R;Ds
return getHibernateTemplate().get =kh>s$We
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(entity, id); u\R`IZ&O
} lhoq3A
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publicList findAll(finalClass entity){ fu<2t$Cn>
return getHibernateTemplate().find("from `E5"Pmg
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" + entity.getName()); u=;nU(]M '
} !?o$-+a|
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publicList findByNamedQuery(finalString X@qk> /
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namedQuery){ Z.':&7Y
return getHibernateTemplate ggI=I<7M
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().findByNamedQuery(namedQuery); Y^2Qxo3"3
} u:$x6/t
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publicList findByNamedQuery(finalString query, 96pk[5lj{?
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finalObject parameter){ kAN;S<jSE
return getHibernateTemplate eR-=<0Iw;
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().findByNamedQuery(query, parameter);
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} #M?F^u[
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publicList findByNamedQuery(finalString query, 7~"(+f
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finalObject[] parameters){ KO"Jg-6r|
return getHibernateTemplate Pc)VK>.fc
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().findByNamedQuery(query, parameters); g[s\~MF@s
} /^LH
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publicList find(finalString query){ B9e.-Xaf
return getHibernateTemplate().find 'DzBp
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(query); f[Fgh@4cj
} 8b 8\
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publicList find(finalString query, finalObject }B"|z'u
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parameter){ :,NFFN
return getHibernateTemplate().find R6q4 ["
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(query, parameter); 8jggc#.
} 5,
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public PaginationSupport findPageByCriteria 6!+X.+
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(final DetachedCriteria detachedCriteria){ 1GG>.RCP
return findPageByCriteria ^r>f2 x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); m\/,cc@,
} `u#;MUg
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public PaginationSupport findPageByCriteria ]D LZ&5pv
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(final DetachedCriteria detachedCriteria, finalint 4L=$K2R2r
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startIndex){ +_
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return findPageByCriteria x*me'?q
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(detachedCriteria, PaginationSupport.PAGESIZE, E+}GxFG-:
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startIndex); &@YFje6Lcm
} n .f4z<
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public PaginationSupport findPageByCriteria @sw9A93A
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(final DetachedCriteria detachedCriteria, finalint |P~O15V*Q
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pageSize, $A;7Em
finalint startIndex){ P>*Fj4Z~
return(PaginationSupport) }+Rgx@XZ\
s,
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getHibernateTemplate().execute(new HibernateCallback(){ EkJVFHfh
publicObject doInHibernate nW|'l^&
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(Session session)throws HibernateException { ]}z'X!v_@
Criteria criteria = I %|@3=Yc
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detachedCriteria.getExecutableCriteria(session); ,
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int totalCount = ^I X%dzM
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((Integer) criteria.setProjection(Projections.rowCount `d7gm;ykp
@B,j;2eb
()).uniqueResult()).intValue(); o'C~~Vg).
criteria.setProjection .E+OmJwD
"jL1.9%"
(null); tJ=3'?T_k
List items = #^|| ]g/N
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criteria.setFirstResult(startIndex).setMaxResults K;oV"KRK
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(pageSize).list(); Hf VHI1f
PaginationSupport ps = t< sp%zXZ
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new PaginationSupport(items, totalCount, pageSize, T/[f5?p
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startIndex); tNK^z7Dm
return ps; oW0gU?Rr)u
} vO\:vp4fH
}, true); 7\mDBG
} :?HSZocf
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public List findAllByCriteria(final `-VG ?J
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DetachedCriteria detachedCriteria){ fO K|:
return(List) getHibernateTemplate A -Mj|V
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().execute(new HibernateCallback(){ @-0Fe9 n=
publicObject doInHibernate 9khjwt
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(Session session)throws HibernateException { vR7ct av
Criteria criteria = cZqfz
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detachedCriteria.getExecutableCriteria(session); wHx}U M"
return criteria.list(); :^n*V6.4
} YWEYHr;%^?
}, true); 6`acg'sk>
} o`idg[l.
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public int getCountByCriteria(final P{?;T5ap6
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DetachedCriteria detachedCriteria){ 'e F%
Integer count = (Integer) `M&P[.9Pz
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getHibernateTemplate().execute(new HibernateCallback(){ Ua %UbAt
publicObject doInHibernate .}o~VT:!?Y
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(Session session)throws HibernateException { ;_}~%-_
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Criteria criteria = KYp[Gs
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detachedCriteria.getExecutableCriteria(session); tww=~!
return $]C=qM28-
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criteria.setProjection(Projections.rowCount lr,q{;
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()).uniqueResult(); Mm5c8[
} )i;un.
}, true); _6ZzuVv3/
return count.intValue(); +p9-
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} I_ONbJ9]
} "?35C
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用户在web层构造查询条件detachedCriteria,和可选的 =~&VdPZ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [@/ /#}5v
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PaginationSupport的实例ps。 EkjgNEXq
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ps.getItems()得到已分页好的结果集 RND9D\7
ps.getIndexes()得到分页索引的数组 V^WU8x
ps.getTotalCount()得到总结果数 Q=WySIF.
ps.getStartIndex()当前分页索引 lCR!:~
ps.getNextIndex()下一页索引 w9MoT.kI}
ps.getPreviousIndex()上一页索引 M7rIi\4K4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 z8E1 m"
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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 &kzj?xK=(j
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一下代码重构了。 c+g@Z"es
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我把原本我的做法也提供出来供大家讨论吧: k2r3dO@q
Q,gLi\siI
首先,为了实现分页查询,我封装了一个Page类: 4jX3lq|
java代码: x:fW~!Xc6
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/*Created on 2005-4-14*/ 1'JD =
package org.flyware.util.page; 0OnV0SIL
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/** nn+_TMu
* @author Joa u#@RM^738d
* 2z\e\I
*/ (5a1P;_Y
publicclass Page { rQb7?O@-
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/** imply if the page has previous page */ _[t8rl
privateboolean hasPrePage; ?T!)X)A#
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/** imply if the page has next page */ $,ikv?"L
privateboolean hasNextPage; Z.1>
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/** the number of every page */ v7,$7@$:\
privateint everyPage; 6~xBi(m`
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/** the total page number */ qtMD CXZ^n
privateint totalPage; PyBD
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/** the number of current page */ r|eZv<6
privateint currentPage; @kxel`,$e
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/** the begin index of the records by the current u5+|Su
*2e!M^K<
query */ }r%X`i|
privateint beginIndex; O"Q7Rx
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/** The default constructor */ D+RiM~LH8
public Page(){ xr%#dVk
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} [9o4hw
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/** construct the page by everyPage KOhA)
* @param everyPage fuMJdAuY7d
* */ Pw[g
public Page(int everyPage){ !)pdamdA
this.everyPage = everyPage; O9"/
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} k~.&j"K
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/** The whole constructor */ t9cl"F=
public Page(boolean hasPrePage, boolean hasNextPage, =0
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int everyPage, int totalPage, +&i +Mpb
int currentPage, int beginIndex){ Vsnuy8~k
this.hasPrePage = hasPrePage; <hx+wrv
this.hasNextPage = hasNextPage; t0)<$At6J
this.everyPage = everyPage; [p;E~-S
this.totalPage = totalPage; [eUftr9&0
this.currentPage = currentPage; fo0+dzazY
this.beginIndex = beginIndex; )]htm&q5
} SUM4Di7
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/** eq4C+&O&
* @return Wwujh2g"0|
* Returns the beginIndex. EYX$pz(x;
*/ $O)3q
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publicint getBeginIndex(){ ?OlV"zK
return beginIndex; 7 msAhz
} $F'>yop2b
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/** m P'^%TE
* @param beginIndex hrGH}CU"
* The beginIndex to set. @]aOyb@
*/ "vZ!vt#'Y
publicvoid setBeginIndex(int beginIndex){ Qnd5X`jF#
this.beginIndex = beginIndex; RsJ6OFcWV
} D B E4&
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/** Bun><Y
@
* @return 5L,}e<S$
* Returns the currentPage. sarq`%zrk
*/ ',^+bgs5
publicint getCurrentPage(){ Uyx!E4pl(
return currentPage; ~@.%m"<.
} 3&&9_`r&_
jhbonuV_
/** )lk&z8;.=
* @param currentPage 0&_UH}10
* The currentPage to set. Vv1|51B
*/ ?L&|Uw+
publicvoid setCurrentPage(int currentPage){ $-}e; V Zb
this.currentPage = currentPage; *^%Q0mU[
} I/gjenUK
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/** b` Hz$8
* @return O3DmNq$dz
* Returns the everyPage. a2Pf/D]n
*/ ,JU@|`
publicint getEveryPage(){ OyV<u@[i
return everyPage; L@`ouQ"sa
} ~w8JH2O
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/** ';Zi@f"
* @param everyPage ~vlype3/EF
* The everyPage to set. ?;/^Ya1;Z
*/ $Iv2j">3)
publicvoid setEveryPage(int everyPage){ W"^wnGa@a
this.everyPage = everyPage; a<}#HfC;'
} ]0hrRA`
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/** JRCrZW}
* @return ./Q,
* Returns the hasNextPage. W@|6nPm
*/ +)o}c"P!
publicboolean getHasNextPage(){
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return hasNextPage; A+hT3;lp
} (jU6GJRP
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/** E|'h]NY
* @param hasNextPage M@0;B30L
* The hasNextPage to set. L|bwZ,M=}?
*/ L_=3<nE
publicvoid setHasNextPage(boolean hasNextPage){ 2^8%>,
this.hasNextPage = hasNextPage; jReXyRmo({
} Xp0F
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/** p-.n3AL
* @return !uQPc
* Returns the hasPrePage. a5a($D
*/ pPd#N'\*
publicboolean getHasPrePage(){ 9]q:[zm^
return hasPrePage; &gzCteS
} T)r9-wOq
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/** C z\Pp q
* @param hasPrePage t%F0:SH
* The hasPrePage to set. R<OI1,..r
*/ sc,Xw:YO
publicvoid setHasPrePage(boolean hasPrePage){ o=0]el^A
this.hasPrePage = hasPrePage; =s<( P1|"
} HRB<Y
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/** s%<eD
* @return Returns the totalPage. [l,Ei?
* 3}e%[AKh
*/ ^o7;c [E`
publicint getTotalPage(){ M)SEn/T-
return totalPage; ;G%R<Z
} eq UME
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/** #8)*1?
* @param totalPage +SwR+H)?
* The totalPage to set. JQ"U4GVp
*/ iX)%Q
publicvoid setTotalPage(int totalPage){ CHz+814
this.totalPage = totalPage; _4g.j
} eUg~)m5G
e=.]F*:J
} ght$9>'n
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aA,!<^&}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 1YH+d0UGn
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个PageUtil,负责对Page对象进行构造: Hro-d1J7
java代码: Dd\jHF>u
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/*Created on 2005-4-14*/ wp&=$Aa)'
package org.flyware.util.page; I1X-s
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import org.apache.commons.logging.Log; AB4(+S*LA
import org.apache.commons.logging.LogFactory; :8OZ#D_Hl
M]J^N#
/** O&Y*pOg
* @author Joa pej|!oX
* 4T ~}
*/ 62zYRs\Y)X
publicclass PageUtil { 1u:<
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privatestaticfinal Log logger = LogFactory.getLog P}4QQw
.4E&/w+
(PageUtil.class); .nVa[B|.
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/** T
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* Use the origin page to create a new page 9?SZNL['V
* @param page U[ 0=L`0e
* @param totalRecords va0{>Dc+
* @return jEZMUqGY!
*/ Rd#WMo2Xd
publicstatic Page createPage(Page page, int ojanBg
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totalRecords){ H*r)Z90
return createPage(page.getEveryPage(), 4GX-ma,
6}FP
page.getCurrentPage(), totalRecords); Jt}Bpg!J
} 32`{7a3!=
V)[@98T_4?
/** 6|PrX
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* the basic page utils not including exception eLfk\kk]Pc
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handler H<PtAYFS
* @param everyPage NeE
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* @param currentPage q-}Fvel u
* @param totalRecords 3v1iy/ /
* @return page UdpF@Q
*/ <4HDZ{"M
publicstatic Page createPage(int everyPage, int AT2n VakL
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currentPage, int totalRecords){ kH
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everyPage = getEveryPage(everyPage); Q$zO83
currentPage = getCurrentPage(currentPage); &B6Ep6QS
int beginIndex = getBeginIndex(everyPage, f,018]|
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currentPage); ;)D];u|_
int totalPage = getTotalPage(everyPage, xHD=\,{ig
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totalRecords); WE: 24b6
boolean hasNextPage = hasNextPage(currentPage, d?A
0MKnl
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totalPage); \1^^\G>H5
boolean hasPrePage = hasPrePage(currentPage); K<>oa[B9
z=q3Zo
returnnew Page(hasPrePage, hasNextPage, iO|se:LY<
everyPage, totalPage, iOW#>66d
currentPage, ^hZ0IM
)b)-ZS7
beginIndex); xc=b
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} ^")Q YE
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privatestaticint getEveryPage(int everyPage){ Y^$X*U/q%U
return everyPage == 0 ? 10 : everyPage; Y 0d<~*
} t gI{`jS%
TFlet"ge=
privatestaticint getCurrentPage(int currentPage){ j+$rj
return currentPage == 0 ? 1 : currentPage; n*[XR`r}
} ;:\<gVi:
M
l Jo`d
privatestaticint getBeginIndex(int everyPage, int _`&m\Qe>
1v.c 6~
currentPage){ Rwz0poG`WG
return(currentPage - 1) * everyPage; *U&0<{|T
} :~Wrf8UQ
;f#v0W`5
privatestaticint getTotalPage(int everyPage, int PQ5QA61
}dgfqq
totalRecords){ 4T|b
Cs?e
int totalPage = 0; Oo5w?+t
`6~Aoe
if(totalRecords % everyPage == 0) "s0)rqf<
totalPage = totalRecords / everyPage; 2$+bJJM
else WW4vn|0v
totalPage = totalRecords / everyPage + 1 ; +ElfZ4
hT`J1nNt
return totalPage; O}-jCW;K
} zzTfYf)
e2s]{obf
privatestaticboolean hasPrePage(int currentPage){ u0|8Tgf
return currentPage == 1 ? false : true; }B\a<0L/
} X' H[7 ^W
RJ 8+h
privatestaticboolean hasNextPage(int currentPage, dCi?SIN
hYPl&^
int totalPage){ I*{4rDt
return currentPage == totalPage || totalPage == + jc!5i .
Q=;U@k@>
0 ? false : true; V58wU:li
} JTO~9>$ B
de.&`lPRf
Dz>^IMsY
} )h"<\%LU
8!O5quEc
uwzvb gup?
[$0p+1
g!@<n1 L
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 e6@=wnoX u
re/@D@%
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 { C=NUK%?
]
o*#t
做法如下: BLfTsNzmt
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *scVJ
JD)(oK%C
的信息,和一个结果集List: \KMToN&2
java代码: !=;+%C&8y
@$S+ Ne[<
S%bCyK%p
/*Created on 2005-6-13*/ & ?h#Z!
package com.adt.bo; s.bc>E0
27
]':A4_
import java.util.List; G18F&c~
sqEI4~514
import org.flyware.util.page.Page; $?Yry.2
/oR0+sH]
/** Dv| #u|iw
* @author Joa @mOH"acGn?
*/ k;K)xb[w |
publicclass Result { U
9_9l7&r
(D#B_`;-
private Page page; Oft-w)cYz,
-I*^-+>H
private List content; H$=e
-L`@
EYtL_hNp}I
/** cii_U=
* The default constructor -~s!73pDY
*/ Rp.Sj{<2
public Result(){ R)_%i<nq\
super(); fol,xMc&
} tNO-e|~'
HJLu'KY}
/** M2PAy! J
* The constructor using fields `NCwK6/i
* od IV:(
* @param page d/PiiiFf,
* @param content x'+T/zw
*/ |jI#"LbF
public Result(Page page, List content){ 3LAIl913
this.page = page; o<|cA5f\
this.content = content; I8wXuIN_
} {@eJtF+2
1C<uz29
/** rSZd!OQ
* @return Returns the content. 'FqQzx"r
*/ Huy5-[)15
publicList getContent(){ k.5u
return content; [$qyF|/K`n
} 7|{}\w(I
;nep5!s;<
/** "fG8?)d;
* @return Returns the page. n!YKz"$
*/ !TAlBkj
public Page getPage(){ f%SZg!+t
return page; [b6R%
} 1pt%Kw*@j
>"|B9Woc
/** C<NLE-
* @param content oC<.=2]
* The content to set. g<l1zo`_
*/ JSkLEa~<
public void setContent(List content){ K~c=M",mW
this.content = content; O{QA
} Id_2PkIN$~
r"C
/** SQ44
* @param page ^Y=\#-Dd
* The page to set. =y
[M\m
*/ .n#@$
nGZ
publicvoid setPage(Page page){ Mmxlp.l
this.page = page; 5*+!+V^?X
} j}%ja_9S
} wb]%m1H`:
cv?06x{
q1z"-~i)E
w$+&3t
a6D &/8
2. 编写业务逻辑接口,并实现它(UserManager, 5~r33L%
MLoYnR^
UserManagerImpl) G}:w@}h/
java代码: p~SClaR3H
wfNk=)^$
RX>xB
/*Created on 2005-7-15*/ dYG,_ji
package com.adt.service; v'U{/ ,x
% 5m/
import net.sf.hibernate.HibernateException; qAAX;N
!ipR$ dM
import org.flyware.util.page.Page; \?Z{hmN
Q3
u8bx|E
import com.adt.bo.Result; w\(.3W7
NL!u<6y
/** ABQa 3{v
* @author Joa OjFLPGRCh
*/ =8t]\Y?
publicinterface UserManager { +aJ>rR
x.f]1S7h[
public Result listUser(Page page)throws 1M}5>V{
/.3}aj;6
HibernateException; ,24p%KJ*X
}@;ep&b*
} UELy"z
R
x,rlrxI
01}C^iD
Q~OxH'>>(
qCljo5Tq'
java代码: U@HK+C"M|
v16JgycM
n2]/v{E;/
/*Created on 2005-7-15*/ hM;lp1l
package com.adt.service.impl; ->l%TCHP
Jl5c
[F
import java.util.List; XWUWY
/LvRP yj@
import net.sf.hibernate.HibernateException; jE}33"
&^#VN%{
import org.flyware.util.page.Page; H7d/X
import org.flyware.util.page.PageUtil; +wEac
g>>E
*]AdUEV?
import com.adt.bo.Result; - db_E#
import com.adt.dao.UserDAO; Jll-`b 1
import com.adt.exception.ObjectNotFoundException; P*
w9,
import com.adt.service.UserManager; }\%Fi/6Z{
K%a%a6k`
/** t/cY=Wp
* @author Joa $"FQj4%d
*/ PK{acen
publicclass UserManagerImpl implements UserManager { jF0jkj1&/[
)+[ gd/<C.
private UserDAO userDAO; P0W*C6&71|
*pSQU=dmS
/** [3(74
* @param userDAO The userDAO to set. +Af"f' )
*/ [U5\bX@$
publicvoid setUserDAO(UserDAO userDAO){ W+PJZn
this.userDAO = userDAO; x c/}#>ED
} E7.2T^o;M
P>s[tM
/* (non-Javadoc) !ePr5On
* @see com.adt.service.UserManager#listUser XZsz/#
mVVD!
(org.flyware.util.page.Page) +3BBQ+x!
*/ 8zRP(+&W
public Result listUser(Page page)throws ZZHDp&lh}
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HibernateException, ObjectNotFoundException { VHCK2}ps
int totalRecords = userDAO.getUserCount(); cki81bOT
if(totalRecords == 0) >4#)r8;dx
throw new ObjectNotFoundException Y0x%sz5
5Ow[~p"l<
("userNotExist"); Y8m1M-#w
page = PageUtil.createPage(page, totalRecords); .#rJ+.2
List users = userDAO.getUserByPage(page); `(YxI
returnnew Result(page, users); umiBj)r
} E%rk[wI
;$smH=I
} d8[J@M53|T
L1cI`9
ZUoxMm
\6R,Nq
w8MG(Lq1"
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @JD;k>
QR%mj*@Wle
询,接下来编写UserDAO的代码: 2w["aVr
=
3. UserDAO 和 UserDAOImpl: ,1 [q^-9
java代码: '}fzX2Q#
)n2 re?S
%Z):>'
/*Created on 2005-7-15*/ *=(lyx_O
package com.adt.dao; gDQ1?N'8{t
9y<*8bI
import java.util.List; f"%{%M$K
+y&Tf#.V/A
import org.flyware.util.page.Page; y%%}k
bgK'{_o-
import net.sf.hibernate.HibernateException; 7R6ry(6N
a-=8xs'
/** ^pQCNKLBY
* @author Joa y#U+c*LB
*/ D;;!ODX$?
publicinterface UserDAO extends BaseDAO { gBC@38|6)
,.OERw
publicList getUserByName(String name)throws (NF~Ck$#q
_3TY,l~
HibernateException; n=y[CKS
%-c*C $
publicint getUserCount()throws HibernateException; hw=
Ft4L
+RyjF~[e
publicList getUserByPage(Page page)throws ;[M}MFc/`
!,6c ~ w
HibernateException; *7ZN]/VRT
OmIg<v0\;
} &Low/Y'.jJ
\$*7 >`k
LUM@#3&
0{,Z{&E
dep=&
java代码: (Iaf?J5{
`$W_R[
'}B+r@YCN
/*Created on 2005-7-15*/ Q9Kve3u-i
package com.adt.dao.impl; mi,E-
P<M?Qd1.
import java.util.List; $W!!wN=B
kBD>-5Sn_T
import org.flyware.util.page.Page; $5ak_@AC
P)Rh=U
import net.sf.hibernate.HibernateException; j g8fU
import net.sf.hibernate.Query; 57umx`m
"1L$|
import com.adt.dao.UserDAO; G(p`1~xm
Wu[&Wv~
/** { g/0x,-Z
* @author Joa /v-6WSN
*/ }\\KYyjY
public class UserDAOImpl extends BaseDAOHibernateImpl _'{_gei_P
amOnqH-(
implements UserDAO { Ji>o!
nxWY7hU
/* (non-Javadoc) Gd-'Z_ b
* @see com.adt.dao.UserDAO#getUserByName <<+\X:,
G Uon/G8
(java.lang.String) "4riSxEyF
*/ j4jTSLQ\
publicList getUserByName(String name)throws =g9*UzA"O
|=`~-i2W
HibernateException { /aZ+T5O
String querySentence = "FROM user in class VUPXO
"alyfyBu'M
com.adt.po.User WHERE user.name=:name"; a
yCY~=i
Query query = getSession().createQuery JtEo'As:[
1IC~e^"
(querySentence); 5ni~Q 9b
query.setParameter("name", name); T
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return query.list(); b{L/4bu
} Ta(Y:*Ri
[d(U38BI
/* (non-Javadoc) nbm&wa[
* @see com.adt.dao.UserDAO#getUserCount() 1FlX'[vh
*/ U+:m4a
publicint getUserCount()throws HibernateException { _+K_5IO4
int count = 0; >7I15U
String querySentence = "SELECT count(*) FROM Cd,jDPrw
FbS|~Rp~
user in class com.adt.po.User"; gW>uR3Ca4
Query query = getSession().createQuery gQ'zW
oU056
(querySentence); g!lWu[d
count = ((Integer)query.iterate().next $Tu61zq
iV'k}rXC
()).intValue(); N/%WsQp
return count; /178A;Jy
} H*ow\
Ct
'p>Ra/4
/* (non-Javadoc) mZSD(
* @see com.adt.dao.UserDAO#getUserByPage _jLL_GD
DI:]GED"=
(org.flyware.util.page.Page) NdMb)l)m
*/ nuk*.Su
publicList getUserByPage(Page page)throws =Xi07_8Ic<
3Dng1}
HibernateException { :~2vJzp@?
String querySentence = "FROM user in class 2% L LSa
dIN$)?aB0
com.adt.po.User"; {1UQ/_
Query query = getSession().createQuery 1_9<3,7
&dM.
d!
(querySentence); yXSFjcoB
query.setFirstResult(page.getBeginIndex()) w_.F'
E
.setMaxResults(page.getEveryPage()); ,K9*%rW)
return query.list(); G`cHCP_n
} )'l:K.F
j[`j9mM8
} n^Hm;BiE#
NQBpX
s}w{:Hk,x8
h2Ld[xvCu%
)J2mM
至此,一个完整的分页程序完成。前台的只需要调用 }>>1<P<8-
'u *DA|HC
userManager.listUser(page)即可得到一个Page对象和结果集对象 ,:%CB"J
[pbo4e,4O
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?9e_gV{&;
O_`VV*
webwork,甚至可以直接在配置文件中指定。 */sS`/Lx
ojcA<60
'
下面给出一个webwork调用示例: 5rw 7;'
java代码: dP3CG8w5
Y<N5#
);f
01wX `"I
/*Created on 2005-6-17*/ mk.9OhYY
package com.adt.action.user; B
Wk/DVue
zr-*$1eu
import java.util.List; tXNm$Cq.|
\UPjf]&
import org.apache.commons.logging.Log; _Gn2o2T
import org.apache.commons.logging.LogFactory; Y~c|hfL
import org.flyware.util.page.Page; = bfJ^]R
7%5z p|3
import com.adt.bo.Result; u(@$a4z
import com.adt.service.UserService; '))0Lh
l
import com.opensymphony.xwork.Action; L-ET<'u
??^5;P{yx
/** GWZ
}7ake
* @author Joa +O8%Hm
*/ !hJ+Lp_
publicclass ListUser implementsAction{ 5eLtCsHz
q
?|,O;?
privatestaticfinal Log logger = LogFactory.getLog %KsEB*'"
m8A#~i .
(ListUser.class); 6 eLR2
C[ NSkr
private UserService userService; Lt u'W22
YmL06<Mh
private Page page; 95ZyP!
Rw"sJ) /
privateList users; CS2Bo
( /=f6^}
/* ]OM"ZG/^
* (non-Javadoc) c/D+|X*
* {j9{n
* @see com.opensymphony.xwork.Action#execute() ,k24w7K%d
*/ V3&RJ k=b
publicString execute()throwsException{ 2M.fLQ?
Result result = userService.listUser(page); Kz~ps
5
page = result.getPage(); D9<!mH
users = result.getContent(); N4v~;;@(
return SUCCESS; <fZyAa3}
} ?^7t'`zk
{x|[p_?
/** 8m-U){r!U^
* @return Returns the page. \HqNAE2T
*/ 6c}h(TkB
public Page getPage(){ "H7dft/
return page; sZjQ3*<-r
} G? ])o5
"i
nd$Z`c
/** Lb!Fcf|h
* @return Returns the users. ?qP7Y nl
*/ &q3"g*q
publicList getUsers(){ FEW14U'O
return users; M||+qd W!
} *{YlN}vA
Bc(Y(X$PK
/** +NeOSQSj
* @param page (uXL^oja
* The page to set. Jb0`42
*/ tRs [ YK
publicvoid setPage(Page page){ {>}!+k
-`
this.page = page; aT{_0m$G10
} v|gw9
Hkk/xNP
/** ?Y$JWEPJ
* @param users w{Ivmdto
* The users to set. ^hG-~z<
*/ ^UciW
publicvoid setUsers(List users){ C;;Sih5
this.users = users; c?tBi9'Y]
} q_Q/3rh
y0Fb_"}
/** &:;:"{t}Do
* @param userService ~FZ&.<s
* The userService to set. xu>9(,l
*/ &b.=M>\9Q
publicvoid setUserService(UserService userService){ F0pir(n-
this.userService = userService; 35A|BD)q
} ?8I?'\F;
}
zkt+7,vI
<->{
o15-ZzE-
Tre]"2l
<Q3oT
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, RU'=ERYC
Cw
iKi^m
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 1Lc#m`Jln
6o!!=}'E[
么只需要: p09HL%~R
java代码: BHIRHmM<Y
Lco~,OE
~d
o9;8v
<?xml version="1.0"?> Sj-n;F|=X
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork cpe+XvBuK
HD@$t)mn
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 3]OE}[R
o~U$GBg
1.0.dtd"> H7?Vy bg~
++bf#qS<8D
<xwork> v6[!o<@"a
^T( .k=
<package name="user" extends="webwork- T%x}Y#U'`
|Z|-q"Rf
interceptors"> |+"<wEKI
niiA7Ux
<!-- The default interceptor stack name ySk R>y
sz5MH!/PJ
--> fWCo;4<5?
<default-interceptor-ref x5|I
%G3h?3
name="myDefaultWebStack"/> FGPB:
,QOG!T4
<action name="listUser" +cD<:"L'g
Qn^'
class="com.adt.action.user.ListUser"> dl.N.P7}4
<param dah[:rP,n{
mH54ja2
name="page.everyPage">10</param> 5 z~1Dw
<result __lM7LFL
V("{)0~O
name="success">/user/user_list.jsp</result> T!-\@PB !
</action> y>R=`A1b
4qN{n#{+]
</package> Rh3eLt~|(
}elc `jj
</xwork> ~<P
0]ju
a[v0%W ]u
v:EB*3n5
:Gv1?M
~fBtQGdX
WKQ^NEqr3
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 =Ee&da^MB
~{?_p@&n
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 /Y*WBTV'
7@#>bE6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 h&|[eZt?F
HvUxsdT
YSs)HV.8
062,L~&E
"MxnFeLM#
我写的一个用于分页的类,用了泛型了,hoho Okgv!Nt8)A
c4!^nk]
java代码: osciZ'~
[N FFB96
yxonRV$&
package com.intokr.util; Om \o#{D
ylUb9KusOx
import java.util.List; d]`CxI]
\/E>4)MD y
/** B*qi_{Gp
* 用于分页的类<br> Pih tf4i
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !y#"l$"xK
* <3(LWxw
* @version 0.01 uvgdY
* @author cheng h}-3\8 >
*/ 1ofKt=|=
public class Paginator<E> { |o,YCzy|5
privateint count = 0; // 总记录数 d[[]PX
privateint p = 1; // 页编号 cD@(/$wt
privateint num = 20; // 每页的记录数 .=U#eHBdAQ
privateList<E> results = null; // 结果 Pnw]Tm}g
zh4#A
<e
/** 1pQn8[sc@
* 结果总数 Ulhk$CPA
*/ }L
&^xe
publicint getCount(){ m 2-Sx
return count; =Xm@YVf&ZD
} (As#^q\>B
k[0-CB
publicvoid setCount(int count){ (VS5V31"
this.count = count; ?xK8#
} 1m+p;T$
X"MB|Ny
/** fz;iOjr>
* 本结果所在的页码,从1开始 vVj
* BW-`t-,E;
* @return Returns the pageNo. tv>>l%
*/ CF&NFSti^
publicint getP(){ dL:-Y.?0M
return p; 85lCj-cs
} M=.:,wRm
=nz}XH%=
/** soPLA68
* if(p<=0) p=1 (
Wa
* "rTQG6`
* @param p Q)"C&)`l
*/ aF8fqu\
publicvoid setP(int p){ Yv
hA_v
if(p <= 0) OtSL*'7>
p = 1; )_a~}
U]=.
this.p = p; |}23>l7
} Mc#*wEo)8
-g)9R%>-
/** j0Bu-sO$w
* 每页记录数量 R=.4
*/ 9F6F~::l}
publicint getNum(){ L}GC<D:
return num; *Kyw^DI
} R,)}>X|<
#G|qD
/** Z -,J)gW
* if(num<1) num=1 e'~Zo9`r6
*/ qe #P?[
publicvoid setNum(int num){ YRv&1!VLE
if(num < 1) Jm|+-F@I
num = 1; dX\.t<
this.num = num; K6y :mJYp\
} Mb"J@5P[4
lJ+0P2@h*
/** )v]/B+
* 获得总页数 sBu=e7
*/ 1h>yu3O
publicint getPageNum(){ ub7zA!%
return(count - 1) / num + 1; lAzjN~V
} f}Np/
Wqc)Fv70m
/** #BJG9DFP4`
* 获得本页的开始编号,为 (p-1)*num+1 !E,A7s
*/ ?gJOgsHJP
publicint getStart(){ m.px>v-
return(p - 1) * num + 1; ^F2b
hXE
} I+Jm>XN
)>b.;
/** $KUos+%
* @return Returns the results. \
W?R
*/ W ZazJ=27}
publicList<E> getResults(){ {D?50Q
return results; =1O<E
} XQ%?
-:Fe7c
public void setResults(List<E> results){ xfy1pS.[:
this.results = results; #mZpeB~
} 6lkl7zm
YFE&r
public String toString(){ ?q(\=;Y
StringBuilder buff = new StringBuilder !:|TdYrmj
B.g[c97
(); BBH0OiV=
buff.append("{"); YoN*:jB<M
buff.append("count:").append(count); [cTe54n
buff.append(",p:").append(p); vo\fUT@k
buff.append(",nump:").append(num); %{(x3\ *&
buff.append(",results:").append hX`hs-*qM
\Y|~2Ls8tu
(results); 'eo
KZX+
buff.append("}"); i<H wTmm$
return buff.toString(); B=>RH!&
} Q:|l`*.R
K=C!b?
} o Y1';&BO9
rj6tZJZ#o0
4l!@=qwn