Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <5sfII
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 uQW d1>
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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 [{_K[5i
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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 .fY$$aD$4
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分页支持类: ra\|c>[%
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java代码: Y[fbmn^
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package com.javaeye.common.util; a3(f\MMxE
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import java.util.List; aK9zw
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publicclass PaginationSupport { ;WL0
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publicfinalstaticint PAGESIZE = 30; P99s
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privateint pageSize = PAGESIZE; ^EKf_w-v
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privateList items; R~BW=Dz,e
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privateint totalCount; !E\J`K0_e
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privateint[] indexes = newint[0]; gr$H?|n l
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privateint startIndex = 0; yAVt[+0
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public PaginationSupport(List items, int aeF^&F0
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totalCount){ W-ECmw(
setPageSize(PAGESIZE); Bk~M ^AK@~
setTotalCount(totalCount); .'N#qs_
setItems(items); i'vjvc~
setStartIndex(0); q]t^6m&-
} Ad`jV_z
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public PaginationSupport(List items, int 8f|+045E@
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totalCount, int startIndex){ %AuS8'Uf
setPageSize(PAGESIZE); '~'3x4Bo
setTotalCount(totalCount); @BXV>U2B{
setItems(items); tA{<)T
setStartIndex(startIndex); Ehf{Kl
} V?cUQghHg
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public PaginationSupport(List items, int 5($
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totalCount, int pageSize, int startIndex){ S>p>$m,
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setPageSize(pageSize); -^7n+
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setTotalCount(totalCount); uc;QSVWGy8
setItems(items); doaqHri\,
setStartIndex(startIndex); tt>=Vt'
} h9J
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publicList getItems(){ RpY#_\^hI
return items; _u`W$EG
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} tMy@'nj
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publicvoid setItems(List items){ yf6&'Y{
this.items = items; \(bML#I
} W1J7$
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publicint getPageSize(){ [HENk34
return pageSize; \6${Na'\
} Au/n|15->C
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publicvoid setPageSize(int pageSize){ CR$5'#11)
this.pageSize = pageSize; mWM!6"
} ZK]C!8\2|
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publicint getTotalCount(){ +P <Lo I
return totalCount; +<H)DPG<
} -.E<~(fad
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publicvoid setTotalCount(int totalCount){ ]Z\.Vx
if(totalCount > 0){ R#Bdfmldq
this.totalCount = totalCount; z7J2O
int count = totalCount / u-. _;
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pageSize; X;0DQnAI8j
if(totalCount % pageSize > 0) <[7.+{qfW
count++; f"5vpU^5*
indexes = newint[count]; [nlW}1)46
for(int i = 0; i < count; i++){ Tce2]"^;
indexes = pageSize * `D%bZ%25c
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} Hd)4_
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}else{ dLm~]V3
this.totalCount = 0; =6TD3k6(2
} OPwj*b:-m
} ( Qw"^lE3
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publicint[] getIndexes(){ ;HJ|)PN5L
return indexes; g+k0Fw]!
} u#Qd`@p
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publicvoid setIndexes(int[] indexes){ eg-,;X#
this.indexes = indexes; Bn/{J
} GV([gs
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publicint getStartIndex(){ v>71?te
return startIndex; @DrMaTr
} Khxl'qj
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publicvoid setStartIndex(int startIndex){ \5Jpr'mY5
if(totalCount <= 0) m$:o+IH/
this.startIndex = 0; b{t'Doe
elseif(startIndex >= totalCount) }cG!93
this.startIndex = indexes 7!`,P
=?3D:k7z
[indexes.length - 1]; t3b%f`D
elseif(startIndex < 0) ^l6q
this.startIndex = 0; *O|Z[>
else{ Llk4 =p
this.startIndex = indexes {ls$#a+d
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[startIndex / pageSize]; 0t1WvW
} )sVz;rF<
} 5/Q^p"
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publicint getNextIndex(){ b$+.}&M
int nextIndex = getStartIndex() + J]~LmSh
R$=UJ}>
pageSize; n=n!Hn
if(nextIndex >= totalCount) EOjo>w>
return getStartIndex(); k9.2*+vvg
else }}v;V*_V
return nextIndex; [|\~-6"7N|
} 8|`4D 'Ln
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publicint getPreviousIndex(){ )G0a72
int previousIndex = getStartIndex() - iU\WV
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pageSize; 1_!*R]a q
if(previousIndex < 0) rm NqS+t
return0; pUWj,&t
else Zycu3%JI
return previousIndex; z)r)w?A
} bH&Cbme90-
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} _U)DL=a'
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抽象业务类 iNgHx[*?
java代码: XS]=sfN
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/** 2![.Kbqa%
* Created on 2005-7-12 AW4N#gt8',
*/ 'c\zWmAZ
package com.javaeye.common.business; wGE:U`
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import java.io.Serializable; C XZm/^
import java.util.List; n0kBLn
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import org.hibernate.Criteria; q3B#rje>h
import org.hibernate.HibernateException; [ottUS@
import org.hibernate.Session; O2?ye 4uq
import org.hibernate.criterion.DetachedCriteria; ._"U{
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import org.hibernate.criterion.Projections; ](4V3w.
import ;OQ{
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org.springframework.orm.hibernate3.HibernateCallback; l
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import 3HC aZ?Ry'
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org.springframework.orm.hibernate3.support.HibernateDaoS
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upport; l~wx8
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import com.javaeye.common.util.PaginationSupport; -@-cG\{
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public abstract class AbstractManager extends M;={] w@n
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HibernateDaoSupport { ]L%qfy4
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privateboolean cacheQueries = false; |_8-3
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privateString queryCacheRegion; 6$w)"Rq
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publicvoid setCacheQueries(boolean I2(5]85&]s
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cacheQueries){ qdrk.~_
this.cacheQueries = cacheQueries; 1Dg\\aUk
} 6+A<_r`#Q
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publicvoid setQueryCacheRegion(String f@+[-yF
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queryCacheRegion){ J{Ei+@^/9
this.queryCacheRegion = :bFmw dX
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queryCacheRegion; 0#KDvCBJ
} meT~b
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publicvoid save(finalObject entity){ |S|0'C*
getHibernateTemplate().save(entity); ~T9%%W[
} hV])\t=yf
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publicvoid persist(finalObject entity){ ngj=w;7~+
getHibernateTemplate().save(entity); I4ZL+a
} Mb=vIk{Bf
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publicvoid update(finalObject entity){ snOd
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getHibernateTemplate().update(entity); v-J*PB.0p
} 2Otd
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publicvoid delete(finalObject entity){ aErms-~
getHibernateTemplate().delete(entity); \,i9 m9;y
} aG}ju;
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publicObject load(finalClass entity, m+||t
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finalSerializable id){ nellN}jYsM
return getHibernateTemplate().load ByoSwQ
}(z[
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(entity, id); #"fBF/Q
} N%%2!Z#
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publicObject get(finalClass entity, N_lQz(nG/2
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finalSerializable id){ *P_(hG&c
return getHibernateTemplate().get }20
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(entity, id); H%>
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} G1 z[v3T
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publicList findAll(finalClass entity){ (wU<Kpt?J
return getHibernateTemplate().find("from B>*zQb2:
"<H.F87Z)
" + entity.getName()); %eB 0)'
} y{+$B
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publicList findByNamedQuery(finalString ,3&XV%1
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namedQuery){ 2%i_SX[
return getHibernateTemplate eRc+.m[
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().findByNamedQuery(namedQuery); C']TO/2q
} q,3_)ZOq
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publicList findByNamedQuery(finalString query, nfET;:{
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finalObject parameter){ ma[%,u`
return getHibernateTemplate O*xC}$OOn
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().findByNamedQuery(query, parameter); P&"8R
} $$ou qLu
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publicList findByNamedQuery(finalString query, 9J h"1i>x2
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finalObject[] parameters){ e\%+~GUTC=
return getHibernateTemplate 6&_"dg"
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().findByNamedQuery(query, parameters); u+%Ca,6
} /~[+'
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publicList find(finalString query){ /|V!2dQs"
return getHibernateTemplate().find (|+Sbq(o
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(query); (T:OZmEO.
} jA_wOR7$
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publicList find(finalString query, finalObject /RU'~(
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parameter){ wZB:7E%
return getHibernateTemplate().find C4wJSQl_I
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(query, parameter); V}gP'f07zy
} BK`NPC$a
@v{lH&K:;
public PaginationSupport findPageByCriteria &J(+XJM%
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(final DetachedCriteria detachedCriteria){ IX@g].)C
return findPageByCriteria 81Ixs
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6Y?%G>$6
} ]Hr:|2|.
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public PaginationSupport findPageByCriteria vM )2F
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(final DetachedCriteria detachedCriteria, finalint !lxs1!:
ML@-@BaN
startIndex){ 0qP&hybL[(
return findPageByCriteria rP$vZ^/c
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(detachedCriteria, PaginationSupport.PAGESIZE, @!k\Ivd
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startIndex); Mx?]7tI
} XRoMD6qf;
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public PaginationSupport findPageByCriteria l{q$[/J~)
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(final DetachedCriteria detachedCriteria, finalint K5l#dl_T
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pageSize, #m>Rt~(,S
finalint startIndex){ V)x(\ls]SX
return(PaginationSupport) j7r! N^
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getHibernateTemplate().execute(new HibernateCallback(){ [4qCW{x._
publicObject doInHibernate Xc)V;1
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(Session session)throws HibernateException { Cwo(%Wc
Criteria criteria = 9{&APxm
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detachedCriteria.getExecutableCriteria(session); ~yacJU=
int totalCount = : (IPrQ
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((Integer) criteria.setProjection(Projections.rowCount &?+ vHE}
ifA=qn0=}
()).uniqueResult()).intValue(); X3nt*G1dL
criteria.setProjection Bfh[C]yy
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(null); QG{).|pm
List items = yWS#{|o(
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criteria.setFirstResult(startIndex).setMaxResults [HEqMBX=;
n0nf;E
(pageSize).list(); e| AA7
PaginationSupport ps = 4a'O#;ho
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new PaginationSupport(items, totalCount, pageSize, *qx<bY@F
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startIndex); %cIF()
return ps; >y
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} 2kv%k3Q{
}, true); .-kqt^Gc
} kk`BwRh)d;
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public List findAllByCriteria(final /cmnX'z
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DetachedCriteria detachedCriteria){ Ub1?dk
return(List) getHibernateTemplate Y-8qAF?SJ]
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().execute(new HibernateCallback(){ Rg:3}T`~n
publicObject doInHibernate XBJ9"G5
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(Session session)throws HibernateException { 2m`4B_g A
Criteria criteria = :V)W?~Z7B
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detachedCriteria.getExecutableCriteria(session); @(:ah
return criteria.list(); _ F0qqj
}
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}, true); d<*4)MRN
} qF9rY)ifm
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public int getCountByCriteria(final $D,m o2I
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DetachedCriteria detachedCriteria){ tykA69X\W
Integer count = (Integer) pB
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getHibernateTemplate().execute(new HibernateCallback(){ |
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publicObject doInHibernate tE)%*z@<Lt
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(Session session)throws HibernateException { C:tA|<b|
Criteria criteria = P\ yt!S2
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detachedCriteria.getExecutableCriteria(session); ,v"/3Ff{,
return ++KY+j.^
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criteria.setProjection(Projections.rowCount JOj\#!\>k0
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()).uniqueResult(); Z&mV1dxR
} JCIm*6~
}, true); <`dF~
return count.intValue(); qZ!1>`B
} \!UNale
} Y^)VHE]
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用户在web层构造查询条件detachedCriteria,和可选的 _/[n/"gn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1B3,lYBM
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PaginationSupport的实例ps。 B0c} 5V
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ps.getItems()得到已分页好的结果集 .?SClTqg
ps.getIndexes()得到分页索引的数组 }?P~qJ|1
ps.getTotalCount()得到总结果数 t\2myR3
ps.getStartIndex()当前分页索引 }@'xEx
ps.getNextIndex()下一页索引 -X@;"0v
ps.getPreviousIndex()上一页索引 /p,D01Ws}(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 PF .sM(
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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 </y V
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一下代码重构了。 ]P0DPea
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我把原本我的做法也提供出来供大家讨论吧: *f8,R"]-g
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首先,为了实现分页查询,我封装了一个Page类: .<Z7K @
java代码: a73b/_zZ=
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/*Created on 2005-4-14*/ i:#R
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package org.flyware.util.page; BO\l>\)Ir
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/** "sFdrXJ
* @author Joa Coq0Kzhsab
* 2W
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*/ EpGe'S
publicclass Page { [[D}vL8d
P's <M
/** imply if the page has previous page */ )ymF:]QC
privateboolean hasPrePage; `n-e.{O((
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/** imply if the page has next page */ Oe9{`~
privateboolean hasNextPage; 0jv9N6IM
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/** the number of every page */ KHr8\qLH
privateint everyPage; 1jmhh!,
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/** the total page number */ |
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privateint totalPage; RA[` Cp"
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/** the number of current page */ va8:QHdU
privateint currentPage; uMsKF %m
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/** the begin index of the records by the current CjQ_oNI
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query */ NtTLvO6
privateint beginIndex; =mqV&FgRo
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2
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/** The default constructor */ b&~uK"O'7d
public Page(){ %o4d43uZ
C`mXEX5
} ^e>v{AE%
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/** construct the page by everyPage ( kp}mSw
* @param everyPage ZJ=C[s!wu
* */ EZP2Bb5g
public Page(int everyPage){ 0nie>
this.everyPage = everyPage; D3.sR\Hxf
} %n}.E304
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/** The whole constructor */ !+)$;`
public Page(boolean hasPrePage, boolean hasNextPage, `*oLEXYN
n^Z?u9VR
;8
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int everyPage, int totalPage, PLLlo~Bb
int currentPage, int beginIndex){ >4EcV1y
this.hasPrePage = hasPrePage; flLmZ1"
this.hasNextPage = hasNextPage; wuYo@DDU#
this.everyPage = everyPage; q/OraPAB
this.totalPage = totalPage; cJ8*[H<NV
this.currentPage = currentPage; xC;$/u%'
this.beginIndex = beginIndex; n;rOH[P
} F$ h/k^
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/** * n!0
* @return ^|sxbP
* Returns the beginIndex. VDnAQ[T@d
*/ E #ys-t 42
publicint getBeginIndex(){ Z<,gSut'Y
return beginIndex; B8s|VI
} Olxb`x
aRG[F*BY
/**
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* @param beginIndex L<QDC
* The beginIndex to set. Y6N+,FAk+J
*/ |9\Lv$VJ
publicvoid setBeginIndex(int beginIndex){ >a4Bfnf"eI
this.beginIndex = beginIndex; zV80r+y
} T@Q<oNU
B!tte)
/** p>}N9v;Bo
* @return {Zseu$c
* Returns the currentPage. PPq*_Cf
*/ t#pY2!/T3
publicint getCurrentPage(){ Gc 8
return currentPage; .`h+fqa
} O3BU.X1'%
to?"{
/** hXrvb[6
* @param currentPage U_8I$v-~
* The currentPage to set. }bnkTC
*/ Xr)d;@yi
publicvoid setCurrentPage(int currentPage){ pH~JPNng
this.currentPage = currentPage; T8m%_U#b
} ZR QPOy
!CMN/=
/** |y=gp
* @return x<3vA|o
* Returns the everyPage. Rw\DJJrz
*/ ud#8`/!mq
publicint getEveryPage(){ &1u?W%(Px
return everyPage; :<(<tz7dj
} *xjIl<`pK
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/** RI*%\~6t?
* @param everyPage L"-&B$B:
* The everyPage to set. ./g#<
*/ 7r;A
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publicvoid setEveryPage(int everyPage){ '{u#:TTj
this.everyPage = everyPage; P<(mH=K
} QA 9vH'
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/** >5gzo6j/
* @return bG&qgbN>
* Returns the hasNextPage. H5%I?ZXw4
*/ Qv=Z
publicboolean getHasNextPage(){ ge?ymaU$a
return hasNextPage; R 1 b`(
} VsMN i#?
yTvK)4&
/** YOoP]0'L
* @param hasNextPage 1M{#"t{6
* The hasNextPage to set. sI'HS+~pU
*/ 5.E 2fX
publicvoid setHasNextPage(boolean hasNextPage){ >k jJq]A2
this.hasNextPage = hasNextPage; CyU>S}t
} v;8XRR:
lpM{@JC
/** Smux&e
* @return ~zX5}U<R
* Returns the hasPrePage. bDNd
m-
*/ )gLasR.1
publicboolean getHasPrePage(){ !58JK f
return hasPrePage; ~S6N'$^
} CYu8J@(\~g
%G
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/** ?(=B=a[
* @param hasPrePage $g^;*>yr
* The hasPrePage to set. &Os Ritj
*/ 1GdgF?4
publicvoid setHasPrePage(boolean hasPrePage){ ,'6GG+
this.hasPrePage = hasPrePage; q'r3a+
} K\ ]r
K7Vr$,p
/** 5`DH\VD.j
* @return Returns the totalPage. lq5E?B
* "8]170
*/ c 1GP3
publicint getTotalPage(){
f#nmr5F
return totalPage; u"T^DrRlQ
} HXQrtJ
lTP02|eK
/** 'W*F[U*&HP
* @param totalPage rY= #^S
* The totalPage to set. 463dLEd
*/ }{y$$X<:
publicvoid setTotalPage(int totalPage){ gk#rA/x
this.totalPage = totalPage; f+Go 8Lg=M
} OXB-.<
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!
} B" z5j
hH/O2
g1|c?#fwo
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~-%A@Lt
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 QAwj]_
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个PageUtil,负责对Page对象进行构造: :
eFc.>KoD
java代码: 3\G=J
XEEbmIO*<9
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/*Created on 2005-4-14*/ [
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package org.flyware.util.page; >xKRU5
t@n (a
import org.apache.commons.logging.Log; U'G`Q0n
import org.apache.commons.logging.LogFactory; QEKFuY<E+
bl<7[J.
/** LH;G:
* @author Joa Sq,ty{j2%
* i#=X#_
+El
*/ @k,(i=**
publicclass PageUtil { 7p$*/5fk
#O+]ydvT
privatestaticfinal Log logger = LogFactory.getLog #^ #i]{g
ZB&Uhi
(PageUtil.class); Rp*t"HSaAW
^nF$<#a
/** jYz3(mM'J
* Use the origin page to create a new page )}!'VIe^!
* @param page T7~v40jn|
* @param totalRecords AUde_1hi
* @return )S;ps
*/ "r"An"
publicstatic Page createPage(Page page, int ~7a BeD
&7&*As
totalRecords){ cx(F,?SbS
return createPage(page.getEveryPage(), CF"3<*%x
""^BW Re D
page.getCurrentPage(), totalRecords); {;DZ@2|
} Dys"|,F
2*YXm>|1
/** pNFIO
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* the basic page utils not including exception L?+|%[
#>B1$(@
handler pH%c7X/[3L
* @param everyPage MA#!<b('
* @param currentPage sLp
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* @param totalRecords YO0x68
* @return page Ue:T3jp3%
*/ )`7+o9&
publicstatic Page createPage(int everyPage, int Xy<f_
t|QMS M?s
currentPage, int totalRecords){ !\O,dq
everyPage = getEveryPage(everyPage); _ n4ma
currentPage = getCurrentPage(currentPage); F@bCm+z-
int beginIndex = getBeginIndex(everyPage, K<JP9t6Qd
{VG[m@
currentPage); 2z# @:Q
int totalPage = getTotalPage(everyPage, 12xP)*:$
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totalRecords); KocXSh U
boolean hasNextPage = hasNextPage(currentPage, {WOfT6y+
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totalPage); %esZ}U
boolean hasPrePage = hasPrePage(currentPage); (1j$*?iGA
L"6/"L
returnnew Page(hasPrePage, hasNextPage, $ _Bu,;
everyPage, totalPage, /
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currentPage, u>6/_^iq
WCT W#<izm
beginIndex); `Kw8rG\]:
} RmV/wY
kQl cT"R
privatestaticint getEveryPage(int everyPage){ =w$"wzc
return everyPage == 0 ? 10 : everyPage; %E7.$Gj%
} z2V8NUn
rOr1H!
privatestaticint getCurrentPage(int currentPage){ [W=S8>
return currentPage == 0 ? 1 : currentPage; 6_K#,_oZ
} c.A/{a
b\m(0/x
privatestaticint getBeginIndex(int everyPage, int kdPm # $-
w!w _`7[
currentPage){ 6FIoWG"x
return(currentPage - 1) * everyPage; Rbc2g"]
} FXEfD"
DK_v{R
privatestaticint getTotalPage(int everyPage, int u!Nfoq&'u
V?dK *8s
totalRecords){ g]
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int totalPage = 0; <?7,`P:h[
y"L`bl A9}
if(totalRecords % everyPage == 0) O[p^lr(B7
totalPage = totalRecords / everyPage; -U;LiO;N
else L8xprHgL
totalPage = totalRecords / everyPage + 1 ; )r,R!8
&~A*(+S
return totalPage; maEpT43f
} +Z~!n
`$agM@"^
privatestaticboolean hasPrePage(int currentPage){ f%[ukMj&
return currentPage == 1 ? false : true; a{Hb7&
} IetGg{h.
VD&3%G!
privatestaticboolean hasNextPage(int currentPage, ?[1qC=[Z<
15T[J%7f
int totalPage){ 9AddF*B
return currentPage == totalPage || totalPage == J}_Dpb [L
,3--ERf
0 ? false : true; )^>XZ*eK
} t:sq*d
SLjf<.S
F@'rP++4
}
{%~4RZA
C
3XZD4.2
#Q7x:,f
"~2#!bK7
)Z]y.W )
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。 6?.pKFBZ
u#@{%kPW
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 HGQ?(2] 8$
^8l3j4
做法如下: C"^hMsU8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X8SRQO^
\pD=Lv9
的信息,和一个结果集List: QUZQY`'@
java代码: l8AEEG8>
ZIL|
.<8I
n$|c{2]=
/*Created on 2005-6-13*/ z vb}p
package com.adt.bo; 9C)3
b3
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import java.util.List; i Kk"j
+=~%S)9F
import org.flyware.util.page.Page; 5-WRv;
[aM'
/** 3AQ>>) T~
* @author Joa X*9N[#wu6
*/ }wOpPN[4
publicclass Result { pz35trW
LQ(5D_yG.
private Page page; d
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|*c\6 :
private List content; o|;eMO-
=Wk/q_.
/** e_~fJ
* The default constructor zIm_7\e
*/
c(V=.+J
public Result(){ y-\A@jJC5
super(); <k\H`P
} c6Aut`dK
"ryk\}*<
/** ^L-w(r62<
* The constructor using fields #;"D)C
* r -q3+c^+
* @param page iA3>X-x
* @param content d=Df.H+3
*/ jWK@NXMH
public Result(Page page, List content){ ?cs]#6^
this.page = page; +fd@K
this.content = content; rx6-~0!eI=
} A6NxM8ybn+
Ed^uA+D
/** qQxA@kdd
* @return Returns the content. b WbXh$
*/ o`\.I&Ij
publicList getContent(){ .-KtB(t
return content; FJf~vAQ
} JpxbB)/
![@T iM
/** &(1H!
* @return Returns the page. K/2. 1o;9
*/ 'cAc{\)
public Page getPage(){ *j/S4qG
return page; JS/M~8+Et
} )Ab6!"'
hr[B^?6
/** !0ce kSesr
* @param content HUJ|-)"dw
* The content to set. v.Xoq
*/ gE@$~Q>M
public void setContent(List content){ JYwyR++uo
this.content = content; >sQ2@"y)s2
} w!WRa8C
}U%^3r-
/** .~q)eV
* @param page fimb]C I|x
* The page to set. ,jRcl!n`
*/ Il{^
j6
publicvoid setPage(Page page){ [6; N3?+
this.page = page; 69C8-fF0[I
} hI|/>4<
} ,{?q^"
,\o<y|+`S
n$XdSh/
y !<'rg
.!(,$'(@=
2. 编写业务逻辑接口,并实现它(UserManager, Z&FkLww
#e.jY_
UserManagerImpl) [IX*sr
java代码: wfxOx$]zK
4l&"]9D
k7^R,.c@
/*Created on 2005-7-15*/ !TP6=ks
package com.adt.service; ohrw\<xsu
g4:VR:o
import net.sf.hibernate.HibernateException; %5JW<9
9<|m4
import org.flyware.util.page.Page; U_}7d"<| ?
B(j02<-
import com.adt.bo.Result; 8F zHNG
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/** _i3i HR?
* @author Joa tu\mFHvlg
*/ %won=TG8
publicinterface UserManager { LBiowd[
m|pTn#*`
public Result listUser(Page page)throws YC]PN5[1!
vd}*_d
HibernateException; GS\%mPZ
|9>*$Fe"
} 0Injyc*bMF
}A{_L6qx
of9q"h
~~PgF"v
M@|w[ydQG
java代码: U~aWG\h#X
)YuRjBcp,"
rdO@X9z
/*Created on 2005-7-15*/ *FV0Vy
package com.adt.service.impl; )ll?-FZ
T yU&QXb
import java.util.List; BlXX:aZv
/7bw: h;
import net.sf.hibernate.HibernateException; NQ?x8h3
n0_B(997*
import org.flyware.util.page.Page; 4d!S#zx
import org.flyware.util.page.PageUtil; Nd`HB=ShJ
R0%?:!
F
import com.adt.bo.Result; $`|5/,M%QN
import com.adt.dao.UserDAO; -#Np7/
import com.adt.exception.ObjectNotFoundException; I(pb-oY3!I
import com.adt.service.UserManager; jOs
H2^
U.: sK*
/** A j,]n>{
* @author Joa mc?';dEG
*/ a`#S|'oatC
publicclass UserManagerImpl implements UserManager { 0pD
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private UserDAO userDAO; Vo%Yf9C
*|mz_cKu
/** |U#DUqw
* @param userDAO The userDAO to set. wG+=}1X
*/ o]A XT8
publicvoid setUserDAO(UserDAO userDAO){ ;Xqn-R
this.userDAO = userDAO; d7* CwY9"
} Yi 6Nw+$
kl"
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/* (non-Javadoc) -Q#o)o
* @see com.adt.service.UserManager#listUser HOfF"QAR$
qNpu}\L
(org.flyware.util.page.Page) Vt'L1Wr0v
*/ jZRh KT
public Result listUser(Page page)throws KxY$PgcC
e#.\^
HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); ~;[&K%n
if(totalRecords == 0) R2l[Q){!
throw new ObjectNotFoundException W6vf=I@f
lWbZ=x_0
("userNotExist"); G]4OFz+
page = PageUtil.createPage(page, totalRecords); ,+s e
List users = userDAO.getUserByPage(page); d/S+(<g
returnnew Result(page, users); +semfZ)
} rj 3YTu`
4.8nY\_WF
} P*YK9Hl<
\m f*ge\
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:j@8L.<U
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (3VGaUlx
),=@q+{E{
询,接下来编写UserDAO的代码: 1Y#HcW&
3. UserDAO 和 UserDAOImpl: 3[r";Wt#
java代码: Z'Q*L?E8M
%*kLEA*v
"}@i+oS
/*Created on 2005-7-15*/ FI8k;4|V
package com.adt.dao; n$4|PO$X
<c+K3P'3?
import java.util.List; X8b|]Nr
]*3:DU
import org.flyware.util.page.Page; sK&,):"]R
X"j>=DEX
import net.sf.hibernate.HibernateException; JS!*2*Wr
nLj&Uf&
/** @u/H8\.l
* @author Joa yxwW j>c
*/ /Wu |)tx
publicinterface UserDAO extends BaseDAO { U'y,YtF@
3;-^YG
publicList getUserByName(String name)throws (bv,02
hL!QLiF:
HibernateException; zmiZ]uq
tiYOMA
publicint getUserCount()throws HibernateException; vZu~LW@1
-f?A h
publicList getUserByPage(Page page)throws "~/9F
b{M}5~e=B
HibernateException; <'+ %\
+{$QAjW(/
} B76 v}O:
vX;HC'%n
8gC)5Y
Hm
fXe
wzh]97b
java代码: >.<ooWw
YTQps&mD.
J -V49X#
/*Created on 2005-7-15*/ "'a* [%
package com.adt.dao.impl; ]\Xc9N8w
ka/XK[/'
import java.util.List; 02\JzBU
m!O;>D
import org.flyware.util.page.Page; Yp1bH+/u
gcf6\f}\<
import net.sf.hibernate.HibernateException; Dx-KMiQ,"(
import net.sf.hibernate.Query; Tf x :"u
5f^>b\8+ |
import com.adt.dao.UserDAO; zN{JJ3-
R J~%0
/** gg^1b77hT
* @author Joa P=`1 rjPE
*/ 8uch i
public class UserDAOImpl extends BaseDAOHibernateImpl _<zfQZai
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implements UserDAO { 8;8c"'Mn
q'G,!];qL
/* (non-Javadoc) \NK-L."[
* @see com.adt.dao.UserDAO#getUserByName }$kQs!#
hat>kXm2K
(java.lang.String) `uo,__y
*/ ;AIc?Cg
publicList getUserByName(String name)throws y&oNv
xG-
sbo^"&%w
HibernateException { c|AtBgvf
String querySentence = "FROM user in class {G3i0r
rNlW7Y
com.adt.po.User WHERE user.name=:name"; E4i0i!<z
Query query = getSession().createQuery QA;!caNp
3s*(uS(
(querySentence); W3rl^M=r
query.setParameter("name", name);
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return query.list(); + G;LX'B
} >&S0#>wmyG
aWy]9F&C:
/* (non-Javadoc) z;Q<F
* @see com.adt.dao.UserDAO#getUserCount() 2i7e#
*/ F$MX,,4U
publicint getUserCount()throws HibernateException { 55Gtp\L
int count = 0; <rIz Z'D
String querySentence = "SELECT count(*) FROM /6+NU^
@|\R}k%(
user in class com.adt.po.User"; @=Fi7M
Query query = getSession().createQuery E9}{1A
8VQ 24r
(querySentence); x\\~SGd
count = ((Integer)query.iterate().next $uj(G7_
4!#a3=_
()).intValue(); p$E8Bn%[
return count; o[1ylzk}+
} 8K"+,s(%R
bKDA!R2
/* (non-Javadoc) ][;G=oCT
* @see com.adt.dao.UserDAO#getUserByPage Kw5Lhc1V
57,dw-|xi
(org.flyware.util.page.Page) a%vrt)Gx
*/ nFRsc'VT
publicList getUserByPage(Page page)throws :5fAPK2r<
%|"g/2sF[G
HibernateException { k\`S
lb1
String querySentence = "FROM user in class :6{`~=
)|bC^{kH!l
com.adt.po.User"; nV_8Ke
Query query = getSession().createQuery c#/H:?q?a
V5`^Y=X(%
(querySentence); &M/>tEZ)
query.setFirstResult(page.getBeginIndex()) I+(/TP
.setMaxResults(page.getEveryPage()); M*eJ
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return query.list(); 3oy~=
} (C;I*cv
HQP}w%8x
} h"+ `13
MV>$BW
*QGm//b
1O/
g&u
t.Nb?/
至此,一个完整的分页程序完成。前台的只需要调用 2&!bfq![
.L6Zm U
userManager.listUser(page)即可得到一个Page对象和结果集对象 .;7> y7$*
-O!/Jv"{,[
的综合体,而传入的参数page对象则可以由前台传入,如果用 rN)V[5R#M
{a(&J6$VE
webwork,甚至可以直接在配置文件中指定。 I@#;nyAj"
Dnf*7)X
下面给出一个webwork调用示例: LOy0hN-$b
java代码: =
u[#2!
hr05L<?H
a>O9pX
/*Created on 2005-6-17*/ J%lgR
package com.adt.action.user; )\uO9PB[O
81LNkE,
import java.util.List; nC1zzFFJ
(~~w7L
s
import org.apache.commons.logging.Log; "es?=
import org.apache.commons.logging.LogFactory; 4NN$( S-W
import org.flyware.util.page.Page; :Y,BdU
/Ci*Az P
import com.adt.bo.Result; Kf tgOG
f
import com.adt.service.UserService; VZ&
A%UFC
import com.opensymphony.xwork.Action; '(GiF
!TM*o+;
/** =3ioQZ^Vz
* @author Joa _5
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*/ 'B5^P
publicclass ListUser implementsAction{ ?S$i?\Qh
l:#-d.z#
privatestaticfinal Log logger = LogFactory.getLog XQ%4L-rhN
YKmsQ(q`N
(ListUser.class); Z/;Xl~
XW{>-PBg:
private UserService userService; 0& >H^
SP* fv`
private Page page; v3d&*I
".^VI2T
privateList users;
_A13[Mt3
xL|;VyD
/* S"Lx%
* (non-Javadoc) j>uj=B@
* ;V^pL((5J
* @see com.opensymphony.xwork.Action#execute()
@fv}G>t
*/ ez]tAW
publicString execute()throwsException{ <f@"HG
l
Result result = userService.listUser(page); zZcnijWb
page = result.getPage(); qyC=(v
users = result.getContent(); m5mu:
return SUCCESS; 6 DG@?O
} p'7*6bj1
e:H26 SW
/** tCxF~L@
* @return Returns the page. m,C1J%{^
*/ d8-A*W[
public Page getPage(){ F
return page; WE]e
m
>
} KL$bqgc(p3
^7zu<lX
/** kmzH'wktt
* @return Returns the users. lj+u@Z<xA
*/ W>-Et7&2
publicList getUsers(){ w 4[{2
return users; oh#\]c\f
} 4DZ-bt'
*5 w{8
/** 4_Dp+^JF
* @param page ()&~@1U
* The page to set. wtje(z5IL
*/ Eu"_MgD
publicvoid setPage(Page page){ {uzf"%VtP
this.page = page; pTIf@n6I
} )95f*wte
p<=$&*
/** W9NX=gE4
* @param users *CHI2MB
* The users to set. dy_:-2S
*/ =zQN[
publicvoid setUsers(List users){ ;WR,eI..
this.users = users; 9tF9T\jW
} #o1=:PQaC
:
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/** N('&jHF
* @param userService (#+^&1
* The userService to set. 2eMTxwt*S
*/ jLg9H/w{
publicvoid setUserService(UserService userService){ A}eOFu`
this.userService = userService; mI 74x3 [
} .^B*e6DAD
} oudxm[/U
[eTSZjIN7
m2AnXY\
8WnwQ%;m?
sr8cYLm5R
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, j?'GZ d"B
.W js~0c
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 t!RiU ZAo
!47n[Zs
么只需要: SdD6 ~LS
java代码: k:7(D_
;!yQ
Gz.|]:1
<?xml version="1.0"?> H%D$(W
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 21"1NJzP
F'0O2KQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- t5 G9!Nn
X&kp;W
1.0.dtd"> Kr)a2rZ}SL
1I:+MBGin
<xwork> O%bEB g
](hE^\SC
<package name="user" extends="webwork- KCs[/]
R17?eucZ
interceptors"> h$2</J"
#\=F O>
<!-- The default interceptor stack name yqPdl1{Qr=
!r<pmr3f@7
--> &Xf}8^T<V
<default-interceptor-ref 4<BjC[@~Z{
wb0L.'jyR)
name="myDefaultWebStack"/> 1y}Y9mlD.
{;2PL^i
<action name="listUser" Zu7)gf
kGl~GOB
a
class="com.adt.action.user.ListUser"> .[_L=_.
<param lnjXDoVb<
5 sX+~Q
name="page.everyPage">10</param> vam;4vyu
<result 5 aCgjA11
?`?)QE8
name="success">/user/user_list.jsp</result>
094o'k
</action> *WuID2cOI
{tWf
</package> ^~etm
')cMiX\v
</xwork> 9iQq.$A .
F%RRd/'
|!4K!_y
1eF3`
tS6qWtE
vw9@v` k
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 M!o##* *`
iUN Ib
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。 VXwU?_4J.
#"G]ke1l$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,0!}7;j_c
-Ps!LI{@
*_d7E
8A})V8
$|@
(
我写的一个用于分页的类,用了泛型了,hoho [MUpxOAsd
) AvN\sC
java代码: glDu2a,Q
3ca (i/c
{ttysQ-
package com.intokr.util; [DI+~F
?82xdpg
import java.util.List; 7fZDsj:
GBPo8L"9
/** rD3v$B
* 用于分页的类<br> <eWf<
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^'PWI{ O
* xqu}cz
* @version 0.01 K &N
* @author cheng (5-FV p
fb
*/ ,s"^kFl
public class Paginator<E> { sYI-5D]
privateint count = 0; // 总记录数 H&