Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 i=OPl
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 tH,}_Bp
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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 oJK1~;:
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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 H{
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分页支持类: 5"%r,GM U
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java代码: jw?/@(AC6
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package com.javaeye.common.util; Q#Q]xJH
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import java.util.List; -D?T0>
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publicclass PaginationSupport { kA1]o
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publicfinalstaticint PAGESIZE = 30; tsVQXvo
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privateint pageSize = PAGESIZE; }-?_c#G3
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privateList items; VC5LxA0{
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privateint totalCount; 28[hp[<
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privateint[] indexes = newint[0]; xy)Y)yp
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privateint startIndex = 0; nd*9vxM
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public PaginationSupport(List items, int dP63bV
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totalCount){ 9g3e( z@
setPageSize(PAGESIZE); ,r~pf(nz
setTotalCount(totalCount); SxMmy
setItems(items); ^
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setStartIndex(0); ^ZV1Ev8T6
} /?uA{/8
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public PaginationSupport(List items, int Aq674
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totalCount, int startIndex){ dZcRLLR
setPageSize(PAGESIZE); &?UIe]
setTotalCount(totalCount); hEla8L4Y
setItems(items); C1&~Y.6m
setStartIndex(startIndex); *"Yz"PK
} IaMZPl
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public PaginationSupport(List items, int C^9G \s'
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totalCount, int pageSize, int startIndex){ 2L"$p?
setPageSize(pageSize); J&Ig%&/
setTotalCount(totalCount); \) DJo
setItems(items); S.&=>
setStartIndex(startIndex); gZ
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} l2H-E&'=
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publicList getItems(){ F]o&m::/K
return items; '-C%?*ku
} cV^r_E\m
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publicvoid setItems(List items){ -OV:y],-
this.items = items; n7-|\p!xP6
} kS_oj
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publicint getPageSize(){ vEQw`OC
return pageSize; S:!gj2q9|
} pFE&`T@ <
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publicvoid setPageSize(int pageSize){ X*f#S:kiNU
this.pageSize = pageSize; ,liFo.kT8%
} K+2k}Hx6J
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publicint getTotalCount(){ p5F=?*[}
return totalCount; @o4+MQFn
} 9vIqGz-o
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publicvoid setTotalCount(int totalCount){ `y"(\1
if(totalCount > 0){ \l)Jb*t
this.totalCount = totalCount; <X>lA
int count = totalCount / Tx+!D'>
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pageSize; Y:o\qr!Y
if(totalCount % pageSize > 0) bEO\oS
count++; hd+(M[C<9
indexes = newint[count]; Vyy;mEBg
for(int i = 0; i < count; i++){ NMaZ+g!t(
indexes = pageSize * {jyI7r#X
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i; ZiR },F/
} Q=B>Q
}else{ ~nQ= iB
this.totalCount = 0; g2?kC^=z=
} ~!V5Ug_2
} j:|um&`)
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publicint[] getIndexes(){ |l \!
return indexes; VkFvV><"
} .\Z/j
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publicvoid setIndexes(int[] indexes){ O_v8R7 {
this.indexes = indexes; rE->z
} ]o!rK<
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publicint getStartIndex(){ o7:~C]
return startIndex; xi+bBqg<.K
} X283 . ?
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publicvoid setStartIndex(int startIndex){ B=ckRWq
if(totalCount <= 0) w^Mj[v#
this.startIndex = 0; 8m prK`p
elseif(startIndex >= totalCount) 4n9".UHh
this.startIndex = indexes S['rfD>9
R #f*QXv
[indexes.length - 1]; ]VKM3[
elseif(startIndex < 0) k<&zVV'
this.startIndex = 0; xX !`0T7Y
else{ V
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this.startIndex = indexes *+i1m`6Q
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[startIndex / pageSize]; )X2/_3
} +nIjW;RU
} `MLOf
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publicint getNextIndex(){ {`ghX%M(l
int nextIndex = getStartIndex() + UR|Au'iu
mf W}^mu
pageSize; u\y$<
if(nextIndex >= totalCount) i^SPNs=
return getStartIndex(); 3|0wD:Dy
else QomihQnc
return nextIndex; G`e!Wv C
} u*S-Pji,x
w paI}H#
publicint getPreviousIndex(){ Ql1J?9W
int previousIndex = getStartIndex() - Z}AhDIw!G
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pageSize; ?8/T#ox
if(previousIndex < 0) W; zzc1v
return0; xxQgX~'x
else .WVIdVO7
return previousIndex; hDf!l$e.
} h
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} ]~@uStHn
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抽象业务类 U1)!X@F{
java代码: `uof\D<']
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/** ^
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* Created on 2005-7-12 H1d2WNr[
*/ v[\Z^pccgj
package com.javaeye.common.business; F|&%Z(@a
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import java.io.Serializable; Sw.Kl
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import java.util.List; Rr0]~2R
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import org.hibernate.Criteria; 8xt8kf*k
import org.hibernate.HibernateException; (,R\6
import org.hibernate.Session; Rjn%<R2nW
import org.hibernate.criterion.DetachedCriteria; qV)hCc/ ~
import org.hibernate.criterion.Projections; u)[i'ceQZ:
import bHg 0,N
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org.springframework.orm.hibernate3.HibernateCallback; IqFmJs|C
import `4,]Mr1b
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org.springframework.orm.hibernate3.support.HibernateDaoS *>k6n5%
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upport; ETm:KbS
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import com.javaeye.common.util.PaginationSupport; MM*9Q`cB
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public abstract class AbstractManager extends cv_t2m
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HibernateDaoSupport { bD=R/yA
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privateboolean cacheQueries = false;
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privateString queryCacheRegion; zp\_5[qJ;
} x
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publicvoid setCacheQueries(boolean xLP8*lvy
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cacheQueries){ a1x].{
this.cacheQueries = cacheQueries; 0x#
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} 65GC7 >[
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publicvoid setQueryCacheRegion(String 3}B-n!|*
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queryCacheRegion){ 93/`e}P"o
this.queryCacheRegion = rIX 40,`
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queryCacheRegion; p
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} = gcZ RoL
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publicvoid save(finalObject entity){ b/4gs62{k
getHibernateTemplate().save(entity); lUiO |
} xR;z!Tg)
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publicvoid persist(finalObject entity){ I#xhmsF
getHibernateTemplate().save(entity); I]B9+Z?xo
} h1#l12k^'
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publicvoid update(finalObject entity){ J?Rp
getHibernateTemplate().update(entity); v%QCp
} /x/W>J2
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publicvoid delete(finalObject entity){ ?[
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getHibernateTemplate().delete(entity); yCv"(fNQ
} ,88%eX|
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publicObject load(finalClass entity, ktv{-WG2_
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finalSerializable id){ !)c0
return getHibernateTemplate().load /Wy9".
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(entity, id); vf`]
} +*RpOtss
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publicObject get(finalClass entity, *gI9CVfQl
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finalSerializable id){ =IIE]<z
return getHibernateTemplate().get E}]SGU"
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(entity, id); Pv@;)s(-
} !" : arK
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publicList findAll(finalClass entity){ \g|;7&%l3
return getHibernateTemplate().find("from UKSI"/8I
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" + entity.getName()); OL[_2m*;9p
} wSs78c=
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publicList findByNamedQuery(finalString (yz8}L3
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namedQuery){ Vs[!WJ
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return getHibernateTemplate }Z\+Qc<<
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().findByNamedQuery(namedQuery); {c$%3iQq
} "?sLi
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publicList findByNamedQuery(finalString query, 2qkC{klC^M
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finalObject parameter){ 7h/{F({r=
return getHibernateTemplate 9a_(_g>S
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().findByNamedQuery(query, parameter); VAR/"
} %K]nX#.B&
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publicList findByNamedQuery(finalString query, O~&l.>??
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finalObject[] parameters){ }(XvI^K[^
return getHibernateTemplate ihhnB
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().findByNamedQuery(query, parameters); XC{(O:EG
} yc 5n
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publicList find(finalString query){ O^gq\X4}
return getHibernateTemplate().find P6 G/J-
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(query); JGD{cr[S
} efP2 C\
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publicList find(finalString query, finalObject L=}UApK
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parameter){ Vt4}!b(O
return getHibernateTemplate().find bvR*sT#rg
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(query, parameter); #(*WxVE
} @]#+`pZ4A
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public PaginationSupport findPageByCriteria Bv@m)$9\+3
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(final DetachedCriteria detachedCriteria){ cuk2\> Xl
return findPageByCriteria P [nWmY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); TzL40="F
} O x$|ZEh
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public PaginationSupport findPageByCriteria Z#o\9/{(R
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(final DetachedCriteria detachedCriteria, finalint )Y&De)=
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startIndex){ YJ16vb9
return findPageByCriteria IfXLnD^||
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(detachedCriteria, PaginationSupport.PAGESIZE, H@j ^,
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startIndex); #=.h:_9
} VYAe!{[
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public PaginationSupport findPageByCriteria \!V6` @0KC
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(final DetachedCriteria detachedCriteria, finalint :A{-^qd(
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pageSize, zuPH3Q={
finalint startIndex){ e #OU {2X
return(PaginationSupport) w9PY^U.Y3e
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getHibernateTemplate().execute(new HibernateCallback(){ (_08?cN
publicObject doInHibernate TnaIRJ\B
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(Session session)throws HibernateException { 5UM[Iz
Criteria criteria = n|*V
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detachedCriteria.getExecutableCriteria(session); XN0Y#l
int totalCount = E{ ,O}
D_)vGvv3;.
((Integer) criteria.setProjection(Projections.rowCount Q}T9NzOH%
@&W?e?O ~G
()).uniqueResult()).intValue(); G9[-|[j^N
criteria.setProjection ]x G4T>S
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(null); "%]dC{
List items = ybG)=0
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criteria.setFirstResult(startIndex).setMaxResults S_CtEM
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(pageSize).list(); O?WaMfS[1
PaginationSupport ps = D.6dPzu`
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new PaginationSupport(items, totalCount, pageSize, A!kyga6F5
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startIndex); z)~!G~J]
return ps; l}2WW1b(
} gsp7N
}, true); bSghf"aN
} dL`
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public List findAllByCriteria(final TH!8G,(w
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DetachedCriteria detachedCriteria){ ,no:6
return(List) getHibernateTemplate | dwxea
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().execute(new HibernateCallback(){ 72zuI4&
publicObject doInHibernate }6>J
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(Session session)throws HibernateException { Cpcd`y=IN
Criteria criteria = NR&9:?
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detachedCriteria.getExecutableCriteria(session); )<F\IM
return criteria.list(); Zbh]OCN
} O97bgj]
}, true); q'U5QyuC
} 3{:<z4>{
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public int getCountByCriteria(final k)V%.Eobf
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DetachedCriteria detachedCriteria){ ~+egu89'TU
Integer count = (Integer) xPup?oP >
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getHibernateTemplate().execute(new HibernateCallback(){ d$rUxqB.
publicObject doInHibernate KB R0p&MN
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(Session session)throws HibernateException { BQ&q<6Tk
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); N"RYM~c7
return iv+jv2ZF%
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criteria.setProjection(Projections.rowCount UX`DZb+^
qmeml_(W
()).uniqueResult(); |p -R9A*>h
} MlK`sH6
}, true); asN
}
return count.intValue(); h+~df(S.
} Y\e]2
} nQ17E{^pR
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用户在web层构造查询条件detachedCriteria,和可选的 cia-OVX
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 V.Ba''E7
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PaginationSupport的实例ps。 (vAv^A*i}
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ps.getItems()得到已分页好的结果集 25a#eDbqi
ps.getIndexes()得到分页索引的数组 Cld<D5\|f+
ps.getTotalCount()得到总结果数 "bR'Bt
ps.getStartIndex()当前分页索引 B >u,)
ps.getNextIndex()下一页索引 P"9@8aLB
ps.getPreviousIndex()上一页索引 $FQcDo|[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;Lsjh#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 O+o ;aa6
umm \r&]A
一下代码重构了。 VZ2.w4b
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我把原本我的做法也提供出来供大家讨论吧: pfL2v,]g
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首先,为了实现分页查询,我封装了一个Page类: &$m=^
java代码: *9dV/TT~f[
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/*Created on 2005-4-14*/ >G<\1R
package org.flyware.util.page; Sf'i{xye
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/** Bw3F7W~l
* @author Joa V;iL[
* Iys6R?~
*/ |"CJ
publicclass Page { Ql~#((K
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/** imply if the page has previous page */ TRgY :R_
privateboolean hasPrePage; >`hSye{
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/** imply if the page has next page */ Mx/h?}u;
privateboolean hasNextPage; S}.\v<
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/** the number of every page */ Z!wD~C"D73
privateint everyPage; /rIm7FW)
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/** the total page number */ YO@hE>
privateint totalPage; 6Cl+KcJH
cs K>iN
/** the number of current page */ \R8 6;9ov
privateint currentPage; h'B9|Cm
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/** the begin index of the records by the current kU#:I9PO
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query */ tCZpfZ@+=
privateint beginIndex; T$H2'tK|
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/** The default constructor */ @<vF]\Ce
public Page(){ `0yb?Nk `:
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} `6rrXU6|
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/** construct the page by everyPage \4OK!6LkI
* @param everyPage 'oC$6l'rQ
* */ M} O[`Fx{W
public Page(int everyPage){ %z1{Kus
this.everyPage = everyPage; M|U';2hZN:
} xttYn]T
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/** The whole constructor */ LL{t5(- _
public Page(boolean hasPrePage, boolean hasNextPage, /ca(a\@R
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;)gLjF/F7
int everyPage, int totalPage, DWuRJ
int currentPage, int beginIndex){ e:qo_eSC^-
this.hasPrePage = hasPrePage; u-lrTa""z
this.hasNextPage = hasNextPage; SLSF
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this.everyPage = everyPage; !0b%Jh
this.totalPage = totalPage; =Wj{]&`
this.currentPage = currentPage; l x7Kw%
this.beginIndex = beginIndex; JdtPY~k0
} 1x{XE*%;
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/** s}jlS
* @return w.tW=z5
* Returns the beginIndex. s){Q&E~X
*/ [4Y[?)7
publicint getBeginIndex(){ VW {,:Ya
return beginIndex; ?k"0w)8
} 9-b 8`|s
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/** C]/&vh7ta
* @param beginIndex ^ZR8s^X
* The beginIndex to set. z=B<
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*/ I:nI6gF
publicvoid setBeginIndex(int beginIndex){ AhR0zg
this.beginIndex = beginIndex; pOKeEW<q
} *y{+W
"tKNlHBu'
/** Gp,'kw"I
* @return <E SvvTf
* Returns the currentPage. b]w[*<f?
*/ `T=1<Tw c
publicint getCurrentPage(){ X3AwM%,!
return currentPage; Gh'X.?3
} cg{Gc]'1#
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/** :Z[(A"dA
* @param currentPage bTiBmS
* The currentPage to set. iyc$)"w
*/ } #qQ2NCH
publicvoid setCurrentPage(int currentPage){ @*SA$9/l
this.currentPage = currentPage; lr0M<5d=p
} ).Q[!lly
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/** t?HF-zQ
* @return hox< vr4
* Returns the everyPage. S_$nCyaH2
*/ <W2ZoqaV
publicint getEveryPage(){ HJ",Sle
return everyPage; QAi1,+y]7w
} L@?e:*h
%7 /,m
/** xvB8YW"
* @param everyPage >P<'L4;
* The everyPage to set. &*A:[b\
*/ me:iQ.g
publicvoid setEveryPage(int everyPage){ ??j&i6sp
this.everyPage = everyPage; _-RyHgX
} @+E7w6>%
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/** K'V 2FTJI
* @return cf\&No?-p
* Returns the hasNextPage. #Skj#)I"
*/ uRpBeH]Z"
publicboolean getHasNextPage(){ 6#vI;d[^
return hasNextPage; HD H
} h9jc,Xu5X
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/** 5D
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* @param hasNextPage ~?d>fR:X
* The hasNextPage to set. '-.wFB;
*/ B$j' /e-Zk
publicvoid setHasNextPage(boolean hasNextPage){ W"t"X ~T3
this.hasNextPage = hasNextPage; ]VDn'@uM
} Bq;1^gtpe
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/**
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* @return
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* Returns the hasPrePage. /?U!y?t&@
*/ .6Fsw
publicboolean getHasPrePage(){ ^e%k~B^
return hasPrePage; <]'|$8&jY
} -K^41W71
}uiPvO+&p
/** -;/
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* @param hasPrePage Why"G1`
* The hasPrePage to set. \447]<u
*/ sG1BNb_
publicvoid setHasPrePage(boolean hasPrePage){ `S$sQ&
this.hasPrePage = hasPrePage; m1V- %kUI
} A2BRbwr>
|6*Va%LYO-
/** shzG
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* @return Returns the totalPage. - wWRm
* K~3Ebr
*/ zi.mq&,]R
publicint getTotalPage(){ LihdZ )
return totalPage; 'kEG.Oq7
} Qt~B#R.
V
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/** v2=/[E@
* @param totalPage s`1^*Dl%+
* The totalPage to set. 'kQ~
*/ y]^#$dK(z
publicvoid setTotalPage(int totalPage){ /GN4I!LA
this.totalPage = totalPage; -=sf}4A
} *m&%vj.Kc
}Aw47;5q;
} yKlU6t&`
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 gb(#DbI
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个PageUtil,负责对Page对象进行构造: Q0WY$w1<
java代码: |(&oI(l5K
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/*Created on 2005-4-14*/ fyrd`R
package org.flyware.util.page; yf?W^{^|
Z)5klg$c
import org.apache.commons.logging.Log; OW#_ty_ul
import org.apache.commons.logging.LogFactory; %p*`h43;
5;(0 $4I
/** #fN/LO
* @author Joa |@ *3^'
* sS|<&3
*/ "f<#.}8
publicclass PageUtil { {6:&
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privatestaticfinal Log logger = LogFactory.getLog [aHlu[,
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(PageUtil.class); CC>($k"
*0\k
Z,#BJ
/** yi|:}K$
* Use the origin page to create a new page s.KOBNCFa
* @param page cCk1'D|X[e
* @param totalRecords GZS{&w!
* @return O"8 P#Ed
*/ z1FL8=
publicstatic Page createPage(Page page, int "h$D7 mL
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totalRecords){ aoK4Du{
return createPage(page.getEveryPage(), Xj(>.E{~H
],Ab cTX
page.getCurrentPage(), totalRecords); [?|5oaK
} g4Bg6<;
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/** tpE3|5dZF
* the basic page utils not including exception 9T/<x-FD
A>5S]
handler 9c%(]Rn:
* @param everyPage kHZKj!!R
* @param currentPage sv@}x[L
* @param totalRecords 9a-]T=5Ee
* @return page kr6:{\DU:B
*/ u>1v~3,r#
publicstatic Page createPage(int everyPage, int Sw[=S '(l
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currentPage, int totalRecords){ %$^$'6\77
everyPage = getEveryPage(everyPage); 6B
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currentPage = getCurrentPage(currentPage); Mg&HRE
int beginIndex = getBeginIndex(everyPage, N0=b[%g;n
X9SJ~n
currentPage); .ZM]%[4
int totalPage = getTotalPage(everyPage, Gtf1}UJC
4U:DJ_GN
totalRecords); @i;L Za
boolean hasNextPage = hasNextPage(currentPage, dr}O+7_7%-
&MBOAHhze
totalPage); /\Jc:v#Q
boolean hasPrePage = hasPrePage(currentPage); )_WH#-}
N IO;
returnnew Page(hasPrePage, hasNextPage, bXk:~LE
everyPage, totalPage, zR_9D}
currentPage, 9[B<rz
u)wu=z8
beginIndex); f45x%tha %
} 1V#B]x:
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privatestaticint getEveryPage(int everyPage){ xtG)^x!
return everyPage == 0 ? 10 : everyPage; Ey
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} Be'?#Qe
\nn56o@eN
privatestaticint getCurrentPage(int currentPage){ 3XM Bu*
return currentPage == 0 ? 1 : currentPage; qFB9,cUqh
} \>&@lA
Tq_1wX'\
privatestaticint getBeginIndex(int everyPage, int q_OY sg
)cfp(16
currentPage){ ]=O{7#
return(currentPage - 1) * everyPage; PTfN+
} +ytT)S
\3J+OY
privatestaticint getTotalPage(int everyPage, int ~7F EY0 /
+-xSuR,
totalRecords){ ~GsH8yA_P
int totalPage = 0; A?%XO
%
/1s 9;'I
if(totalRecords % everyPage == 0) ^Y1AeJ$L
totalPage = totalRecords / everyPage; 7=9A_4G!
else A=\'r<:
totalPage = totalRecords / everyPage + 1 ; Jv '3](
3}.mp}K5
return totalPage; mH7CgI
} WHdqO8
LrmtPnL
privatestaticboolean hasPrePage(int currentPage){ R(n0!h4
return currentPage == 1 ? false : true; }kgjLaQ^N
} `"^@[1
s~IA},F,\
privatestaticboolean hasNextPage(int currentPage, S|z(
Cz$Hk;3\6
int totalPage){ =]2RC1#}e
return currentPage == totalPage || totalPage == W}<M?b4tP
Xm0&U?dZB
0 ? false : true; sk%:Sp
} w2M
IY_N?
ajcPt]f
l72ie
} T^-H_|/M
"=v J}
[W8iM7D
i &SBW0)
M25z<Y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 o+6^|RP
l yLK$B?/
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 A<*tn?M]
gw}7%U`T9
做法如下: OA8b_k~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 XQ4^:3Yc
)oz-<zW
的信息,和一个结果集List: f@x( ,p
java代码: >x _:=%Wr+
Hhce:E@K
*|.yX%"k
/*Created on 2005-6-13*/ 6lH>600]u
package com.adt.bo; %lqG* dRx0
7HR%rO?'
import java.util.List; QeOt;{_|
bQ:3G;
import org.flyware.util.page.Page; ]aMa*fF
A?{aUQB~|
/** qT-nD}
* @author Joa WTy8 N
*/ f^yLwRUD
publicclass Result { y0mg}N1
_R!!4Hp<Q
private Page page; 4 *2>R8SX~
jJ{
w -$
private List content; iJp!ROI
+
1%^c(3
/** q'8@0FT0
* The default constructor mYs->mg1
*/ ~6kA<(x
public Result(){ Tk@g9\6O9
super(); |(8Hk@\CT>
} }Us$y0W\
JMe[
.Sx
/** f`";Q/rG
* The constructor using fields >~bj7M6t
* a*wJcJTpV"
* @param page X72X:"
* @param content R"kE5:
*/ y.]]V"'2
public Result(Page page, List content){ v}*u[GWl]
this.page = page; (/P&;?j
this.content = content; TXOW/{B
} IF?B`TmZ
Xs,PT
/** Ak-7}i
* @return Returns the content. 2]3Jb{8FI>
*/ &^D@(m7>{K
publicList getContent(){ }c#/1J7
return content; g[+Q~/yq
} "9T`3cM0
Jt,
4@
/** /Gv$1t^a
* @return Returns the page. 4g^+y.,r_f
*/ 5Cyjq0+
public Page getPage(){ ?{P6AF-xcf
return page; Q>c6ouuJ
} EuA<{%i
Nn7@+g)
/** [cAg'R6
* @param content SpiC0
* The content to set. ,ST.pu8N.
*/ 05LQh
public void setContent(List content){ g*imswj7
this.content = content; fhWD>;%F%
} v!9Imf
c^gIK1f-
/** ~*]`XL.-
* @param page Z_WTMs:x!
* The page to set.
I_s(yO4pw
*/ :Rx"WY
publicvoid setPage(Page page){ zFQkUgb
this.page = page; sBI%lrO
} {
4{{;
} 1Sk6[h'CL
vs5wxTM
`bF;Ew;
s""8V_,;
n{WJ.Y*
2. 编写业务逻辑接口,并实现它(UserManager, ,]qX_`qF
g}KZL-p4\m
UserManagerImpl) M 7$4KFNp
java代码: ,X6j$YLWp
bj{f[nZ d
Mwk_SCy
/*Created on 2005-7-15*/ Q
kpmPQK
package com.adt.service; Khd ,|pM
UH|.@7w
import net.sf.hibernate.HibernateException; t+q`h3
MX\-)e#
import org.flyware.util.page.Page; RyD$4jk+T"
zD-8#H35X"
import com.adt.bo.Result; mj|9x1U)
3<V!y&a
/** AE
_~DZ:%c
* @author Joa 1=.kH[R
*/ EBLoRW=8ld
publicinterface UserManager { }`FPe
/=} vPey
public Result listUser(Page page)throws 9%6`ZS~3
^u,x~nPXg
HibernateException; X\RTHlw']
vn0*KIrX
} Ka{Zoi]
tYa8I/HpT
0yNlf-O
;d40:q<
~T9[\nU\
java代码: 4iW2hV@m
iKY&gnu"
YfKty0
/*Created on 2005-7-15*/ 8ipLq`)
package com.adt.service.impl; g2q=&eI"
q(W@=-uDK
import java.util.List; mNKa~E
Km-B=6*QY
import net.sf.hibernate.HibernateException; +dv@N3GV
'h6RZKG T
import org.flyware.util.page.Page; h6t>yC\
import org.flyware.util.page.PageUtil; a06DeRCej
vxx3^;4p
import com.adt.bo.Result; Xv:IbM>
Qc
import com.adt.dao.UserDAO; |?kH]Trr
import com.adt.exception.ObjectNotFoundException; nj$K4_
import com.adt.service.UserManager; {9MYEN}FO
%54![-@
/** 3F1Z$d(
* @author Joa ./'n2$^3
*/ qfU3Cwy
publicclass UserManagerImpl implements UserManager { <9~qAq7^
n21J7;\/+
private UserDAO userDAO; =qRVKz
sh1()vT
/** k|5nu-B0v
* @param userDAO The userDAO to set. 8Yh2K}
*/ i_"I"5pBF
publicvoid setUserDAO(UserDAO userDAO){ }UrtDXhA
this.userDAO = userDAO; f7'%AuSQ(
} 85mQHZ8aR
iJBZnU:Mp
/* (non-Javadoc) RAC-;~$WB
* @see com.adt.service.UserManager#listUser %}[??R0
!MC Wt
(org.flyware.util.page.Page) 7-DC"`Y8e
*/ Ou^dI
public Result listUser(Page page)throws 1yu!:8=ee
~CA+'e%~~
HibernateException, ObjectNotFoundException { BlUY9`VWh@
int totalRecords = userDAO.getUserCount(); ,l6W|p?ZO^
if(totalRecords == 0) MYDSkW
throw new ObjectNotFoundException 8~i@7~
J
}W<L;yD
("userNotExist"); 7}Sw(g)o7
page = PageUtil.createPage(page, totalRecords); yl}Hr*
List users = userDAO.getUserByPage(page); "{k3~epYaN
returnnew Result(page, users); 9O"?T7i"#
} <Yc:,CU
3jNcL{
} }/VHeHd
.<.qRq-
ZLkJYZk
vXF\PMf
CbZ1<r" /
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 OH~t\fQ1Zf
H2]I__t/u
询,接下来编写UserDAO的代码: =BtEduz
3. UserDAO 和 UserDAOImpl: ')BQ 0sg
java代码: z+b~#f3
W.a/k7 p
^6*? a9jO>
/*Created on 2005-7-15*/ 4M_83WL
package com.adt.dao; j-
A|\:
=N=,;<6%A
import java.util.List; iB?@(10}ES
0pR04"`;
import org.flyware.util.page.Page; H)S3/%.|
EP[
gq
import net.sf.hibernate.HibernateException; rnr7t \a~]
BWs\'B
/** qb_V
,b9
* @author Joa g5E]o)
*/ )L{\k$r!EM
publicinterface UserDAO extends BaseDAO { +,MzD'(D
U0rz 4fxc
publicList getUserByName(String name)throws |0&S>%=
+|.#<]GA
HibernateException; pk/#+r;
_ReQQti[
publicint getUserCount()throws HibernateException; ,Xn%-OT
B0Z@ Cf
publicList getUserByPage(Page page)throws 68y.yX[
+o/q@&v;Ax
HibernateException; /90@ 85%r
g9gyWz
} d1,azM
[)*fN|Hy
dI>oHMC
b#P8Je`;9
ENGw <
java代码: 3{%/1>+x5
PY^Yx$t9
0trFLX
/*Created on 2005-7-15*/ SQeQ"k|P%
package com.adt.dao.impl; YFW+l~[#
\F>
*d!^C
import java.util.List; RH`m=?~J,
U'\\(m|
import org.flyware.util.page.Page; 6G(k{S
ZK13[_@9
import net.sf.hibernate.HibernateException; |BXq8Erh
import net.sf.hibernate.Query; rGN-jb)T+
Y)uNzb6R
import com.adt.dao.UserDAO; GxvVh71zP
)X@(>b{
/** .z_^_@qdm
* @author Joa PKwx)!
Rz
*/ 4
Hu+ljdjB
public class UserDAOImpl extends BaseDAOHibernateImpl J)R2O4OEd
/aK },+
implements UserDAO { 0xPML}|V
K,So#Ui
/* (non-Javadoc) _z}d yp"I
* @see com.adt.dao.UserDAO#getUserByName E&97;VH
m,*f6g
(java.lang.String) onjTuZ^h
*/ 7ed*dXY*
publicList getUserByName(String name)throws '-
Z4GcL
>`6^1j(3
HibernateException { ;B7>/q;g
String querySentence = "FROM user in class YKk%lZ.8
!D
com.adt.po.User WHERE user.name=:name"; $H_4Y-xOi
Query query = getSession().createQuery z\;kjI
K[ylyQ1
(querySentence); 0a(*/u
query.setParameter("name", name); $+?6U
return query.list(); ag] nVE/
} #M_QSD}&
7C&`i}/t
/* (non-Javadoc) u52@{@Ad
* @see com.adt.dao.UserDAO#getUserCount() SK-|O9Ki
*/ @m(\f
publicint getUserCount()throws HibernateException { xvgIYc{
int count = 0; ?Ww',e
String querySentence = "SELECT count(*) FROM YrB-;R1+
F`Pu$>8C
user in class com.adt.po.User"; !FO92 P16
Query query = getSession().createQuery U;;Har
zO!`sPP
(querySentence); Ad]r )d{
count = ((Integer)query.iterate().next S?D2`b
0V1kZ.
()).intValue(); P~?u2,.E[
return count; :pNZQX
} YXBS!89m
Phx/9Kk
/* (non-Javadoc) >0512_J+
* @see com.adt.dao.UserDAO#getUserByPage 5|AZ/!rb
KnbP@!+c
(org.flyware.util.page.Page) ^ 41p+
*/ q/]tJ{FI
publicList getUserByPage(Page page)throws h7o{l7`)
ph69u #Og
HibernateException { 5ptbz<Xv
String querySentence = "FROM user in class Z5NuLB'
<01MXT-
com.adt.po.User"; !WDdq_n*v
Query query = getSession().createQuery CIV6Qe"<
1a%*X UT
(querySentence); p-ry{"XA
query.setFirstResult(page.getBeginIndex()) QAu^]1 ;
.setMaxResults(page.getEveryPage()); 6Q\n<&,{
return query.list(); L@v0C)
} p|W:;(
NbgP,-
} FSH6C2
iPE-j#|
=#1/<q)L
:<nL9y jt
W/J3sAYv
至此,一个完整的分页程序完成。前台的只需要调用 xXLKL6F(\
78 3a Z8
userManager.listUser(page)即可得到一个Page对象和结果集对象 ]jM D'vg^b
'zRd?Z>%
的综合体,而传入的参数page对象则可以由前台传入,如果用 &0Nd9%>
FUMAvVQ
webwork,甚至可以直接在配置文件中指定。 ;/ p)vR
[;};qQ-C2
下面给出一个webwork调用示例: mA{gj[@:x
java代码: LG51e7_gFi
%f?#) 01>
Qza[~6
/*Created on 2005-6-17*/ Qa"R?dfr
package com.adt.action.user; I8?egDkk
|[xi"E\
import java.util.List; EEF}Wf$f
1=#`&f5f&
import org.apache.commons.logging.Log; tjYe82
import org.apache.commons.logging.LogFactory; a!wPBJJ
import org.flyware.util.page.Page; Xa%Z0%{
RU[{!E
import com.adt.bo.Result; 6`%}s3Xq
import com.adt.service.UserService; JCE364$$"
import com.opensymphony.xwork.Action; 9/^4W.
GAPZt4Z2
/** !L> 'g
* @author Joa MQp1j:CK
*/ RkC?(p
publicclass ListUser implementsAction{ 7%L-;xcr]B
#]n[
privatestaticfinal Log logger = LogFactory.getLog V$^x]z
ca$D|3
(ListUser.class); zoO>N'b3)
V@T G"YF
private UserService userService; Cc9<ABv?
8=t?rA
private Page page; l--xq^,`o]
5wr0+Xo
privateList users; g5/8u2d
.LV=Z0ja
/* \:^$ZBQr<n
* (non-Javadoc) 'g( R4deCX
* ])0&el3-
* @see com.opensymphony.xwork.Action#execute() XWk/S $-d
*/ &\K,kS [.r
publicString execute()throwsException{ t+p-,ey^@
Result result = userService.listUser(page); )p ,-TtV
page = result.getPage(); '[:].?M
users = result.getContent(); , lT8gQ|u
return SUCCESS; 9?l(
}S`
} "'s`?
N4'b]:`n
/** 7zpwP
* @return Returns the page. mqwN<:
*/ u~%
m(
public Page getPage(){ {h|3P/?7
return page; S ^2'O7uj
} $Pl>T09d
6 3Kec
/** u.$.RkNMQ
* @return Returns the users. v"y
e\ZG
*/ Koahd=
publicList getUsers(){ bbS'ZkB\
return users; ]X@/0
} _U/etlDTO
Iu%/~FgPj{
/** T\. 8og
* @param page /vSFQ}W
* The page to set. SAly~(r?/
*/ d<fS52~l
publicvoid setPage(Page page){ nr-VzF7zu
this.page = page; <N+l"Re#]
} -&@[]/
5N`g
/** oKzV!~{0M;
* @param users 9]7+fu
* The users to set. uqX"^dn4u
*/ nolTvqMT
publicvoid setUsers(List users){ OlMCF.W#3
this.users = users; TJLz^%t
} N~Ax78TX
UU$ +DL
/** - stSl*
* @param userService S7~yRIjB
* The userService to set. (:M6*RV
*/ +-
c#UO>
publicvoid setUserService(UserService userService){ _mA[^G=gY
this.userService = userService; o NJ/AT
} nPvR
} 5orA#B
F2>o"j2
LEHlfB#z`@
"R4~
8 r
bZERh:%o
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, u&2uQ-T0
yd#4b`8U`
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 khc5h^0
Zff-Hl
么只需要: |~#!e}L(
java代码: pd>EUdbrp&
q+|Dm<Ug
$?wX*
<?xml version="1.0"?> {lx^57v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork gHYYxhW$
_EjS(.e/=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- f^m8 4o'
YC*S;q
1.0.dtd"> [rE,fR
VEE:Z^U!
<xwork> wyvs#T
,i,f1XJ|
<package name="user" extends="webwork- ;t[<!
R"=G?d)
interceptors"> YNk?1#k?i
GMB%A
<!-- The default interceptor stack name lZ/Yp~2S
EQu M|4$ix
--> 1=W>zC
<default-interceptor-ref xxiEL2"`>
A%%WPBk{O
name="myDefaultWebStack"/> O_KL#xo
19;\:tN
<action name="listUser" =GFlaGD
\u",bMQF
class="com.adt.action.user.ListUser"> vF1]L]z:?
<param g0_8:Gs}^
nJA\P1@m
name="page.everyPage">10</param> AGPZd9
<result o`h F1*yp
'OkF.bs
name="success">/user/user_list.jsp</result> MLId3#Q
</action> ,#D&*
PlTY^N6Hn
</package> 3mr9}P9;
IuB0C!'
</xwork> NWb,$/7T
>qAQNX
mhT3 Fwc
b _cD
>A
.* VZY
cKF 8(
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 ;]vE"M x$
~{RXc+
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。 o!\Vk~Vi&
X;ijCZb3b
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 oy#Qj3M8=
ewY+a ,t
BEifUgCh
umSbxEZU@
DoNbCVZ
我写的一个用于分页的类,用了泛型了,hoho u=
!?<Q
K`PF|=z
java代码: |BF4F5wC?
A;q}SO%b
T+N%KRl
package com.intokr.util; qZCA16
v#nYH?+~mJ
import java.util.List; WPCaxA+l
U]d{hY."
/** ON]
z-
* 用于分页的类<br> 9m%[
y1v0
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1+.(N:) +
* q<D'"7#.
* @version 0.01 *d?,i-Q.+
* @author cheng UR:cBr
*/ ;~#rdL
public class Paginator<E> { Jc(tV(z
privateint count = 0; // 总记录数 *<"xF'C
privateint p = 1; // 页编号 !imm17XQ\
privateint num = 20; // 每页的记录数 .E"hsGH9h
privateList<E> results = null; // 结果 /i"L@t)\t
8u!!a^F
/** !T#~.QP4
* 结果总数 $ R,7#7bG
*/ 2u/~#Rt&*
publicint getCount(){ : H0+} =
return count; RU>T?2
} BC9rsb
^CDQ75tR
publicvoid setCount(int count){ p\WW~qD
this.count = count; I+kDx=T!
} 0[ H'l",~
gH(,>}{^K
/** Wg3y
y8vIW
* 本结果所在的页码,从1开始 ^8ZVB.Fv
* ~?H _?}e
* @return Returns the pageNo. aP>%iRk'J!
*/ ?m}vDd
publicint getP(){ 9EIHcUXe
return p; Fi14_{
} nX7{09
?MHVkGD
/** FI`][&]V
* if(p<=0) p=1 2bPrND\P=
* C1:efa<wV
* @param p UpF,e>s
*/ j,Eo/f+j5
publicvoid setP(int p){ C{`+h163\
if(p <= 0) WV]Si2pOZ
p = 1; W>.KV7
this.p = p; 4onRO!G,
} 3P2H!r
"7(2m
/** n,!PyJ
* 每页记录数量 8$xd;+`y'
*/ F4xYfbwY"]
publicint getNum(){ "94e-Nx
return num; E:a_f!
} y'?ksow
\DI%/(?
/** fI9 TzpV
* if(num<1) num=1 3xj
?}o
*/ 8=Xy19<;t
publicvoid setNum(int num){ oJE~dY$Q
if(num < 1) 9lbe[w@
num = 1; LmE%`qNg
this.num = num; 1:h{(
%`&
} se(ZiyHp
JKN0:/t7Q
/** }pxMO? h$
* 获得总页数 9%55R >s$
*/ TUuw
publicint getPageNum(){ gVO<W.?
return(count - 1) / num + 1; -'ePx f
} 'id]<<F
q$6fb)2I]e
/** ?WyL|;b*
* 获得本页的开始编号,为 (p-1)*num+1 cy T,tN
*/ gmtp/?>e
publicint getStart(){ /UtCJMQ
return(p - 1) * num + 1; BV_rk^}Ur
} lMoi5q
zg L0v5vk
/** fn(<
<FA)
* @return Returns the results. ]Y@Db5S$T
*/ jYE<d&Cq
publicList<E> getResults(){ b|F4E{{D^
return results; j:ze5F A+
} H*s_A/$
rV;X1x}l
public void setResults(List<E> results){ /E8{:>2
this.results = results; iG*@(
} BSU%.tmI
|-t>_+. J'
public String toString(){ UolsF-U}'
StringBuilder buff = new StringBuilder a
k&G=a6^
8NU <lV`
(); {6}H}_(]
buff.append("{"); 36MqEUjyB
buff.append("count:").append(count); ai|d`:;
buff.append(",p:").append(p); !Q(x A,p
buff.append(",nump:").append(num); -CePtq`
buff.append(",results:").append 7tbM~+<0
)> >Tj7
(results); ?VUW.-
buff.append("}"); pgNyLgN
return buff.toString(); LEu_RU?
} 21k^MZ
e0rh~@E
} abAX)R'
F<R+]M:fa
)o4B^kq