Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7M$>'PfO
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 |5FyfDaFBX
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 ml3]CcKn
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ;ga~ae=Fg
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分页支持类: #cmj?y()
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java代码: ].Et&v
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package com.javaeye.common.util; .IYE"0)wJ
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import java.util.List; @,s[l1P
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publicclass PaginationSupport { c5t?S@b
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publicfinalstaticint PAGESIZE = 30; Uq[NOJC
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privateint pageSize = PAGESIZE; GbMSO
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privateList items; ikofJl]9
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privateint totalCount; ?5+=
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privateint[] indexes = newint[0]; /O&j1g@
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privateint startIndex = 0; \6sp"KqP
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public PaginationSupport(List items, int C$?dkmIt
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totalCount){ Z$+0gm\Cnw
setPageSize(PAGESIZE); Bh@j6fv
setTotalCount(totalCount); g8B@M*JA
setItems(items); 0P!6
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setStartIndex(0); ;zp0,[r
} g y&B"`
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public PaginationSupport(List items, int WF:i}+g+^
>-]Y%O;}
totalCount, int startIndex){ y&SueU=
setPageSize(PAGESIZE); n32BHOVE
setTotalCount(totalCount); L.erP*
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setItems(items); oU{m\r
setStartIndex(startIndex); 2AU_<Hr6
} ^S[Mg6J
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public PaginationSupport(List items, int :}j{ NM#
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totalCount, int pageSize, int startIndex){ Rb\\6BU0
setPageSize(pageSize); (u RAK
setTotalCount(totalCount); 0h$23.
setItems(items); S^~GI$
setStartIndex(startIndex); >D*L0snjV
} +]Ydf^rF
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publicList getItems(){ *R8q)Q
return items; qM]eK\q 1
} ?mrG^TV^+r
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publicvoid setItems(List items){ LUJKR6oT{>
this.items = items; l*/I ;a$
} @@_f''f$
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publicint getPageSize(){ `|Tr"xavf
return pageSize; \~U8<z
} JZN'U<R
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publicvoid setPageSize(int pageSize){ W}nD#9tL
this.pageSize = pageSize; HPm12&8,
} C:z K{+
@
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publicint getTotalCount(){ kcI3pmgj
return totalCount; Oe*emUX7
} EubF`w$KWX
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publicvoid setTotalCount(int totalCount){ T/uj5pMG
if(totalCount > 0){ G'Jsk4:c
this.totalCount = totalCount; Al6)$8]e
int count = totalCount / oJ>]=^?k
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]
pageSize; <<Ut@243\
if(totalCount % pageSize > 0) (*BQd1Z
count++; EO3?Dev
indexes = newint[count]; 7k{C'\m
for(int i = 0; i < count; i++){ (q"Nt_y
indexes = pageSize * '$;S?6$eW
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i; Hj$JXo[U
} WOG=Uy$
}else{ i4&"-ujrm
this.totalCount = 0; G2zfdgW${/
} F3i+t+Jt
} Hq3"OMG q
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publicint[] getIndexes(){ q:+,'&<D
return indexes; $62!R]C9\
} &}Cm9V
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publicvoid setIndexes(int[] indexes){ m "h{HgJd
this.indexes = indexes; seB ^o}
} a9` E&Q}z
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publicint getStartIndex(){ oxha8CF]D
return startIndex; bBn4m:
} VE6
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publicvoid setStartIndex(int startIndex){ VW}xY
if(totalCount <= 0) .B+R+2uY3
this.startIndex = 0; >PGW>W$
elseif(startIndex >= totalCount) ZM`6zS!
this.startIndex = indexes w =^QIr%
v&;q4b4
[indexes.length - 1]; ,dLh`t<\
elseif(startIndex < 0) nK)U.SZ
this.startIndex = 0; `rN,*kcP
else{ I>B-[QEC
this.startIndex = indexes 4U*J{''L
2I*
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[startIndex / pageSize]; Q
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} O=?WI
} J 6D?$
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publicint getNextIndex(){ wKIQK!B)mF
int nextIndex = getStartIndex() + =c"`>Vi@d
'%vb&a!.6
pageSize; 5IE 2&V
if(nextIndex >= totalCount) bx_`S#*N
return getStartIndex(); NiQ`,Q$B
else ?|s1Cuc
return nextIndex; [I^>ji0V
} I6,'o)l{_
l\I#^N
publicint getPreviousIndex(){ 4p\<b8(9>
int previousIndex = getStartIndex() - *Fi`o_d9[`
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pageSize; iC10|0%{
if(previousIndex < 0) 7Ps I'1v
return0; 4Z12Z@ A#7
else J\^ZRu_K
return previousIndex; wC+_S*M-K
} BT.;l I
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} _~ZNX+4
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抽象业务类 ze@NqCF
java代码: (A|Gb2 X
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/** a|Io)Qhr
* Created on 2005-7-12 tpOMKh.`
*/ h,o/(GNnW
package com.javaeye.common.business; j6]+fo&3
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import java.io.Serializable; YBqu7&
import java.util.List; uLX5khQ
T[]2]K[&B
import org.hibernate.Criteria; y!)
import org.hibernate.HibernateException; >77N5>]e
import org.hibernate.Session; Y_tLSOD#/
import org.hibernate.criterion.DetachedCriteria; veIR)i@dx
import org.hibernate.criterion.Projections; V3DXoRE-8i
import
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org.springframework.orm.hibernate3.HibernateCallback; F67%xz0
import ()a(PvEO
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org.springframework.orm.hibernate3.support.HibernateDaoS (ZH5/VKp
^}7iouE C
upport; 5#3/
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import com.javaeye.common.util.PaginationSupport; +aR.t@D+"Y
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public abstract class AbstractManager extends 4+2XPaIm
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HibernateDaoSupport { (7/fsfsF
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privateboolean cacheQueries = false; _ZX"gHx
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privateString queryCacheRegion; ]wFKXZeK
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publicvoid setCacheQueries(boolean |W4
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cacheQueries){ S81Z\=eK
this.cacheQueries = cacheQueries; +EK(r@eV
} b~dm+5W7
mCOJ1}
publicvoid setQueryCacheRegion(String uTgBnv(Y*
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queryCacheRegion){ GG%X1c8K
this.queryCacheRegion = {uH
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queryCacheRegion; l`=).k
} 65X31vU
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publicvoid save(finalObject entity){ &S[tI$
getHibernateTemplate().save(entity); o_;pEe
} J%}9"Q5
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publicvoid persist(finalObject entity){ 5y-8_)y8o
getHibernateTemplate().save(entity); >`L)E,=/
} ."b=dkx
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publicvoid update(finalObject entity){ =Lx*TbsFYt
getHibernateTemplate().update(entity); y
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} /xf4*zr
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publicvoid delete(finalObject entity){ 7LMad%
getHibernateTemplate().delete(entity); i\hH .7G1
} f[v~U<\R
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publicObject load(finalClass entity, uMOm<kn
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finalSerializable id){ $T7hY$2Ql
return getHibernateTemplate().load {g9?Eio^F^
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(entity, id); R{{d4=:S
} n.zVCKNH
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publicObject get(finalClass entity, 3?|gBiX
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finalSerializable id){ 2B&Yw
return getHibernateTemplate().get .s$#: ls?
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(entity, id); 8qwc]f$.w
} L-ans2?
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publicList findAll(finalClass entity){ $tvGS6p>
return getHibernateTemplate().find("from [P#^nyOh(
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p;
" + entity.getName()); _J^q|
} 7+]T}4;
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publicList findByNamedQuery(finalString `< 8Fc`;[
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namedQuery){ dbU
return getHibernateTemplate CORX .PQ
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().findByNamedQuery(namedQuery); +o&E)S}wP
} VU,\OOp
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publicList findByNamedQuery(finalString query, [{3WHS.
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finalObject parameter){ o?A/
return getHibernateTemplate 5wXe^G
tm\ <w H
().findByNamedQuery(query, parameter); FI@2KM
} N{n}]Js1D-
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publicList findByNamedQuery(finalString query, i[FcY2
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finalObject[] parameters){ X;_0"g
return getHibernateTemplate -,jJ{Y~
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().findByNamedQuery(query, parameters); Mi'Q5m
} lh`inAt)"
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publicList find(finalString query){ Yjz'lWg
return getHibernateTemplate().find wd*i&ooQ*L
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(query); N>i1TM2
} ]*a)'k_@[
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c
publicList find(finalString query, finalObject &H\$O.?f
@ [_I|
parameter){ Db({k,P'Y
return getHibernateTemplate().find ;cZ9C 1
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(query, parameter); #r 1
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} z79L2lJn
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public PaginationSupport findPageByCriteria cqeId&Cg
uE:#m.Q
(final DetachedCriteria detachedCriteria){ R= HN>(U
return findPageByCriteria S|T:rc(~
[;dWFG"f
(detachedCriteria, PaginationSupport.PAGESIZE, 0); #I9|>XE1
} DoWY*2E
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public PaginationSupport findPageByCriteria xD#PM |I
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(final DetachedCriteria detachedCriteria, finalint ia|^>V>-
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startIndex){ `xe[\Z2
return findPageByCriteria YlOYgr^
4@#1G*OO
(detachedCriteria, PaginationSupport.PAGESIZE, sw*k(i
a AYO(;3
startIndex); RhyI\(Z2q
} qcke8Q
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public PaginationSupport findPageByCriteria ><OdHRh@#
Mr:*l`b_
(final DetachedCriteria detachedCriteria, finalint lj%8(X u
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pageSize, W"Dj+/uS
finalint startIndex){ 9.e?<u*-z
return(PaginationSupport) T,(IdVlJ
Rz`<E97-
getHibernateTemplate().execute(new HibernateCallback(){ 3hR7 ./
publicObject doInHibernate Bt,qG1>$-
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(Session session)throws HibernateException { BieII$\P%P
Criteria criteria = {d(PH7R
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detachedCriteria.getExecutableCriteria(session); .}ZX~k&P
int totalCount = 6f6_ztTL
aGp <%d
((Integer) criteria.setProjection(Projections.rowCount 6N.mSnp
0]8+rWp|Nz
()).uniqueResult()).intValue(); /0SG
criteria.setProjection &{&lCBN
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(null); 3]'=s>UO>^
List items = ni@D7:h
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criteria.setFirstResult(startIndex).setMaxResults #Vn=(U4}!_
mUr@w*kq|p
(pageSize).list(); P?n!fA>!
PaginationSupport ps = psRm*,*O
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new PaginationSupport(items, totalCount, pageSize, EN.yU!N.4
f]T1:N*t
startIndex); g/+M&k$
return ps; l@1f L%f
} hl}#bZ8]
}, true); KtEMH
} )2YU|
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public List findAllByCriteria(final %9mB4Fc6b)
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DetachedCriteria detachedCriteria){ .j88=t0
return(List) getHibernateTemplate 9ciL<'H\
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().execute(new HibernateCallback(){ ^ bM;C_<$f
publicObject doInHibernate e /;Ui
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(Session session)throws HibernateException { b,T=0W
Criteria criteria = Zpb3>0<R
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detachedCriteria.getExecutableCriteria(session); 2l5@gDk5
return criteria.list(); [%l+
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} EUuMSDp
}, true); G&C)`};
} ?2EzNN cS
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public int getCountByCriteria(final N0
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DetachedCriteria detachedCriteria){ |w~zh6~
Integer count = (Integer) rLL;NTN+/
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getHibernateTemplate().execute(new HibernateCallback(){ =Bo0Oei
publicObject doInHibernate SVq7qc9K?
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(Session session)throws HibernateException { CQ,r*VAw
Criteria criteria = E=s`$ A
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detachedCriteria.getExecutableCriteria(session); DvOg|XUU0
return 't)j
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criteria.setProjection(Projections.rowCount g1zqh,
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()).uniqueResult(); vMRKs#&8
} 2DV{gF
}, true); ui 2RTAb
return count.intValue(); GMNf#;x
} u]dpA
} Z,iklB-
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用户在web层构造查询条件detachedCriteria,和可选的 ae!_u
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 IL%&*B
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PaginationSupport的实例ps。 A{+ZXu}
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ps.getItems()得到已分页好的结果集 wkm
SIN:
ps.getIndexes()得到分页索引的数组 pu>LC6m3a
ps.getTotalCount()得到总结果数 ~Q%QA._R?
ps.getStartIndex()当前分页索引 R*&3i$S
ps.getNextIndex()下一页索引 D3^v[>E2
ps.getPreviousIndex()上一页索引 5<a<!]|C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \uPT-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 3t_5Xacj
X*Q7Yu
一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: Ahwu'mgnC
Tf[]vqa`G
首先,为了实现分页查询,我封装了一个Page类: A6U6SvM;
java代码: bg=`
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gTQ6B,`/8
/*Created on 2005-4-14*/ Xs?>6i@$$
package org.flyware.util.page; rU~"A
jS- QTG!=
/**
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* @author Joa 0y ;gi3W
* c`jTdVD
*/ :8QG$Ua1
publicclass Page { b~~}(^Bg
#tfJ?w`
/** imply if the page has previous page */ {U<htl4
privateboolean hasPrePage; 4Sl^cKb$7
:m~lgb<
/** imply if the page has next page */ 9q5[W=|
privateboolean hasNextPage; .s9Iymz
$fn^i.
/** the number of every page */ 4C[gW
privateint everyPage; ?nn,RBS-
J *B`C^i
/** the total page number */ _Ey8P0-I
privateint totalPage; W UV Q_<i+
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/** the number of current page */ i@;a%$5
privateint currentPage; u}h'v&"e,
x-QP+M`Pu
/** the begin index of the records by the current >L(F{c:
VuR BJ2D
query */ x$p\ocA
privateint beginIndex; ejQCMG7
wb?hfe
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/** The default constructor */ E:tUbWVp
public Page(){ rTJWftH!
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} eyG.XAP
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/** construct the page by everyPage Y\=:j7'
* @param everyPage 3k(?`4JJ
* */ S`^W#,rj
public Page(int everyPage){ t2gjhn^p
this.everyPage = everyPage; e8# 3Y+Tc
} \r2qH0B
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/** The whole constructor */ &ar}6eO
public Page(boolean hasPrePage, boolean hasNextPage, .`p_vS9
oF^B J8%Lm
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int everyPage, int totalPage, Ij8tBT?jlL
int currentPage, int beginIndex){ e{O5y8,
this.hasPrePage = hasPrePage; :Ry24X
this.hasNextPage = hasNextPage; %qHT!aP
this.everyPage = everyPage; c%dy$mkqgK
this.totalPage = totalPage; b(VU{cf2d
this.currentPage = currentPage; ~_&.A* Jh
this.beginIndex = beginIndex; +!Ltn
} vqHJc2yYkZ
.s?OKy
/** 4s8E:I=K
* @return >tzXbmFp;
* Returns the beginIndex. _7 ;^od=C
*/ #+G2ZJxL|
publicint getBeginIndex(){ P:TpB6.=q
return beginIndex; ,+RO 5n
} 1L|(:m+
? `KOW
/** ..:V3]-D
* @param beginIndex S#9SAX [
* The beginIndex to set. [:'n+D=T3M
*/ kA_3o)J
publicvoid setBeginIndex(int beginIndex){ yM2&cMHH~
this.beginIndex = beginIndex; l_%~X9"
} 1`t?5|s>
NZuFxJ-`
/** THp `!l
* @return v\eBL&WK
* Returns the currentPage. <7^~r(DP
*/ Zy%Z]dF
publicint getCurrentPage(){ E0Djo'64
return currentPage; $yAfs3/%)s
} QFPx4F7(e
c
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/** >N
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* @param currentPage WdAGZUp
* The currentPage to set. SS~Q ;9o
*/ u^9c`
publicvoid setCurrentPage(int currentPage){ w!RH*S
this.currentPage = currentPage; .7FI%
} "BRE0Ir:
,LZ:y1z'V-
/** L'Zud,JKg
* @return 3c3Z"JV
* Returns the everyPage. Oy&'zigJ
*/ j%;)CV
G"
publicint getEveryPage(){ ArYF\7P
return everyPage; ];;w/$zke
} `1@[uWl
W<VHv"?V
/** !&lPdEc@T
* @param everyPage B6\VxSX4{
* The everyPage to set. (Y)h+}n5N
*/ ?m1$*j
publicvoid setEveryPage(int everyPage){ ]LTc)[5Zj
this.everyPage = everyPage; LDeVNVM
} GJs[m~`8#
c!Vc_@V,
/** J36@Pf]h
* @return L@r.R_*H?s
* Returns the hasNextPage. sV[Z|$&Z
*/ Xb*_LZAU
publicboolean getHasNextPage(){ h\d($Ki
return hasNextPage; rj~ian
} Z!reX6
;;!{m(;LS}
/** :, [!8QP
* @param hasNextPage ]4mj 1g&C
* The hasNextPage to set. ->I{
:#
*/ I%919
publicvoid setHasNextPage(boolean hasNextPage){ 3 ?F@jEQk
this.hasNextPage = hasNextPage; >-lL-%N_
} Qu FCc1Q
X.l"f'`l
/** ~q(C j"7
* @return W;dzLgc
* Returns the hasPrePage. 2gAdZE&Y
*/ ,jsx]U/^
publicboolean getHasPrePage(){ Z(mn
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return hasPrePage; lMez!qx,=
} N>%KV8>{L
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/** g/Jj]X#r
* @param hasPrePage cGta4;
* The hasPrePage to set. IQ=|Kj9h
*/ ,7jiHF
publicvoid setHasPrePage(boolean hasPrePage){ "!6~*!]c
this.hasPrePage = hasPrePage; Y0O<]2yVx
} y~c[sW
ptyDv
/** h)
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* @return Returns the totalPage. o!r4 frP
* BON""yIC
*/ !9 LAXM
publicint getTotalPage(){ t0H=NUP8
return totalPage; irb.F>(x
} u6I0<i_KZ
:YXQ9/iRr
/** Qfu*F}
* @param totalPage 2G5!u)
* The totalPage to set. <VR&=YJ
*/ G!LNP&~
publicvoid setTotalPage(int totalPage){ j_uY8c>3\q
this.totalPage = totalPage; *2
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} #'Y6UGJ\n
a 8hv .43
} (Zn3-t*
q\y#
Y_3YO2K]
`[ ` *@O(y
A;j$rGx
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 FJ,\?ooGf
n[:AV
个PageUtil,负责对Page对象进行构造: Q0uO49sg
java代码: pD_eo6xX
m\Fb ,
5`'au61/2
/*Created on 2005-4-14*/ T{{AZV"pB
package org.flyware.util.page; MY*>)us\
+6)kX4
import org.apache.commons.logging.Log; 2j/1@Z1j=
import org.apache.commons.logging.LogFactory; &Yks,2:P
f.84=epv
/** \v
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* @author Joa 27YLg c
* *o\Y~U-so
*/ dms:i)L2
publicclass PageUtil { X.AWs=:-
'j<:FUDJ
privatestaticfinal Log logger = LogFactory.getLog [(P[qEY
<\9Ijuq}k
(PageUtil.class); \
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u3i|}`
/** M3;v3
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* Use the origin page to create a new page ?]:EmP
* @param page g yH7((#i
* @param totalRecords sEJ;t0.LX
* @return -anFt+f-
*/ dYew7
publicstatic Page createPage(Page page, int m57tOX
S}p&\w H
totalRecords){ yZ~eLWz
return createPage(page.getEveryPage(), `_g?y)
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page.getCurrentPage(), totalRecords);
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} pT;-1c%:
c>WpO Z,
/** 'UXj\vJ3E
* the basic page utils not including exception -G<2R"Q#N
)av'u.]%c
handler 07LL)v~
* @param everyPage W/ZahPPq
* @param currentPage V=zM5 MH2
* @param totalRecords -2jBs-z
* @return page )4F/T, {;m
*/ ]T3BDgu%&
publicstatic Page createPage(int everyPage, int {cyo0-9nv
d,J<SG&L&
currentPage, int totalRecords){ B[/['sD
everyPage = getEveryPage(everyPage); LY88;*:S
currentPage = getCurrentPage(currentPage); e<O;pM:
int beginIndex = getBeginIndex(everyPage, Fb{`a[&
>upXt?
currentPage); kSDa\l!W]
int totalPage = getTotalPage(everyPage, hKzBq*cV
*CPB5s
totalRecords); xlPcg7
boolean hasNextPage = hasNextPage(currentPage, K.iH
k"^t?\Q%vI
totalPage); .M53, 8X
boolean hasPrePage = hasPrePage(currentPage); &b@!DAwAJ
9p\wTzA
returnnew Page(hasPrePage, hasNextPage, 1nlE3Y?AV
everyPage, totalPage, sRe#{EuJ
currentPage, Q!2iOvK
AR+\uD=\I-
beginIndex); s?G'l=CcKu
} sAjKf\][
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privatestaticint getEveryPage(int everyPage){ N9JgV,`
return everyPage == 0 ? 10 : everyPage; Xx y
Bg!R
} & L.PU@
_^xh1=Qr}n
privatestaticint getCurrentPage(int currentPage){ |p8"9jN@}c
return currentPage == 0 ? 1 : currentPage; {sfmWVp
} [`zbf_RyO
!.2CAL
privatestaticint getBeginIndex(int everyPage, int
uRB)g
spSN6.j
currentPage){ 1y)$[e
return(currentPage - 1) * everyPage; eA*Jfb
} O2'bNR
UU;-q_H6
privatestaticint getTotalPage(int everyPage, int ;oY(I7
s7UhC.>'@
totalRecords){ e0|_Z])D
int totalPage = 0; UP~WP@0F
1hMX(N&|
if(totalRecords % everyPage == 0) =~W0 ~lxX
totalPage = totalRecords / everyPage; `r'0"V
else RP|>&I
totalPage = totalRecords / everyPage + 1 ; /:Z~"Q*r
lEyG9Xvi
return totalPage; WK_y1(v>
} GEe 0@q#YA
m_E[bDON
privatestaticboolean hasPrePage(int currentPage){
,3J`ftCV
return currentPage == 1 ? false : true; R!_8jD:$
} rKy-u
V$-~%7@>;9
privatestaticboolean hasNextPage(int currentPage, I4o=6ts
35%[DUkb
int totalPage){ N)vk0IM!
return currentPage == totalPage || totalPage == }o!#_N0T
Xew1LPI
0 ? false : true; StdS$XW
} O7'<I|aD
zU4V^N'
Mg a@JA"
} :Er^"9'A2
:!+}XT7)/
u^aFj%}]L
>2| [EZ
]e@0T{!
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。 !e:iB7<
, N@Yk.
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 E,<\T6/%q
jsNH`"
做法如下: =.qm8+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9k=U0]!ch
JGk3b=K
的信息,和一个结果集List: f.aB?\"f6
java代码: Uw2,o|=O
|b$>68:
$S6HZG:N
/*Created on 2005-6-13*/ }XGMa?WR
package com.adt.bo; Z{,GZT
3wN?|N
import java.util.List; 0|fb< "
n)
_dH/"
import org.flyware.util.page.Page; ;t;Y.*&=S
?fbgU
/** VxkCK02k
* @author Joa ZR;8rZ](
*/ M#\ <
publicclass Result { E[|s>Xv~
BR& Aq
private Page page; hzT{3YtY2
nabBU4;h
private List content; 99l>CYXd
v"P&`1=T
/** Pl rkgS0J
* The default constructor F`Dg*O
*/ K0EY<Ltq
public Result(){ ]6$,IKE7
super(); KGV.S
} !US8aT
c;:">NR
/** \)OZUch
* The constructor using fields u* t,i`
* /9x{^
* @param page g$*/XSr(
* @param content fm(mO%
*/ @4IW=V
public Result(Page page, List content){ up\oWR:
this.page = page;
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this.content = content; b]!9eV$
} G(U 9rJ9
lLb:f6N
/** v ! 7s
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* @return Returns the content. _GVE^yW~z
*/ U@Z>/ q
publicList getContent(){ gM4P j[W
return content; yfmp$GO:
} o&(wg(Rv
8YuJ8KC
/** D(y+1^>
* @return Returns the page.
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*/ wP[xmO-%
public Page getPage(){ j$3rJA%rN
return page; %KGq*|GUu
} yJ!OsD
Z[",$Lt
/** 21r==
H$
* @param content T vrk^!
* The content to set. (GCG/8s
*/ Iz
DG&c
public void setContent(List content){ 8zhBA9Y#~
this.content = content; y }\r#"Z`
} x^A7'ad0
""co6qo#>
/** 1HMUHZT
* @param page T4mv%zzS
* The page to set. q@(1Yivk
*/ zVSx$6eiU
publicvoid setPage(Page page){ f}^I=pS&
this.page = page; y|$R`P
} *)u?~r(F
} 5L8&/EN9-
$}t=RW
sLb8*fak
cA D[3b[Gk
N_ UQ
2. 编写业务逻辑接口,并实现它(UserManager, 9YB2e84j
(+*
][|T
UserManagerImpl) et=7}K]l
java代码: QV7,G9
cv}aS_`f
<OTWT`G2
/*Created on 2005-7-15*/ 5sCFzo<=vh
package com.adt.service; +a%xyD:.?
3gAR4
import net.sf.hibernate.HibernateException; xq}-m!nX
\[yr=X
import org.flyware.util.page.Page; j&5G\6:
)zU:
import com.adt.bo.Result; ]*qU+&
axmsrjW#
/** LheFQ A
* @author Joa $.pTB(tO
*/ NmJ`?-Z
publicinterface UserManager { $B\ H
I,b9t\(6
public Result listUser(Page page)throws ?v:ZU~i
Ga v"C{G
HibernateException; H$!+A
Z7fg
25
} U@'F%nHw
owvS/"@
fAGctRGH
`H\)e%]
v5_7r%Hiw
java代码: "+)K |9T#
OOnX`
CK0l9#g
/*Created on 2005-7-15*/ 3X;{vO\a1
package com.adt.service.impl; 8'A72*dhX
>H>gH2qp
import java.util.List; q/NY72tj0
j(iuz^I
import net.sf.hibernate.HibernateException; ~:4~2d|
=. *98
import org.flyware.util.page.Page; `0{ S3v
import org.flyware.util.page.PageUtil; 5,1{Tv`
U&UKUACn"
import com.adt.bo.Result; 44\cI]!{
import com.adt.dao.UserDAO; /`[!_4i
import com.adt.exception.ObjectNotFoundException; LvcuZZ`1a
import com.adt.service.UserManager; P ZxFZvE
]ab#q=
/** XM/vDdR
* @author Joa Tkw;pb
*/ LH2PTW\b!6
publicclass UserManagerImpl implements UserManager { }u%"$[I}
|S&5es-yW
private UserDAO userDAO; K B!5u 9
[ %}u=}@
/** \ECu5L4
* @param userDAO The userDAO to set. {hQ6K)s
*/ 2C$R4:Ssw)
publicvoid setUserDAO(UserDAO userDAO){ & ze>X
this.userDAO = userDAO; x&Cp> +i
} d--'Rn5
+pf5\#l?
/* (non-Javadoc) 9XLFHV("
* @see com.adt.service.UserManager#listUser WA6!+Gy
#]E(N~
(org.flyware.util.page.Page) ujr(K=E
*/ Y
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public Result listUser(Page page)throws A(8n
S QY"OBo<e
HibernateException, ObjectNotFoundException { t
P"\J(x
int totalRecords = userDAO.getUserCount(); u,1}h L
if(totalRecords == 0) ibpzeuUl
throw new ObjectNotFoundException Pf<[|yu4?
oH#v6{y
("userNotExist");
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page = PageUtil.createPage(page, totalRecords); kM/Te{<
List users = userDAO.getUserByPage(page); EpYy3^5d
returnnew Result(page, users); UG;Y^?Ppe5
} x;LzG t:w
?+0GfIV
} At6qtoPRA
1[;;sSp
usFfMF X
F%d\~Vj
ua5?(,E`']
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 a|4~NL
C3'rtY.
询,接下来编写UserDAO的代码: R@iUCT^$
3. UserDAO 和 UserDAOImpl: XL$* _c <)
java代码: O(z}H}Fv
cXnKCzSxZq
-|S]oJy
/*Created on 2005-7-15*/ HYK!}&
package com.adt.dao; ]Mi.f3QlO6
"*z_O
import java.util.List; UPiW73Nu
,=QM#l]
import org.flyware.util.page.Page; Ju2l?RrX
8RW&r
import net.sf.hibernate.HibernateException; MZ>6o5K|
p(F " /
/** /9pM>Cd*Z
* @author Joa $ ((6=39s
*/ (ljF{)Ml+=
publicinterface UserDAO extends BaseDAO { ])DX%$f
CO:u1?
publicList getUserByName(String name)throws 2@=IT0[E\
j;1 -p>z
HibernateException; hm*cw[#O1x
1oLv.L
publicint getUserCount()throws HibernateException; D*PYr{z'
O81X;JdP3
publicList getUserByPage(Page page)throws errH>D~
!7bw5H
HibernateException; ~EzaC?fQ
GoM
ip8'u
} !y:%0{l
<A5]]{9 +
|RkcDrB~
Q/ms]Du
xNK1h-t
java代码: i_Re*
/u%h8!"R
(-77[+2
/*Created on 2005-7-15*/ Ny- [9S-<
package com.adt.dao.impl; YevyN\,}V!
M:KbD|
import java.util.List; G!N{NCq
RyJ 1mAC
import org.flyware.util.page.Page; A-
YBQPE
*^\HU=&
import net.sf.hibernate.HibernateException; X~=xXN.
import net.sf.hibernate.Query; z4#(Ze@u~_
!" #9<~Q,p
import com.adt.dao.UserDAO; <h).fX
fWc|gq
/** ;22l"-F
* @author Joa CT9
*/ xT&(n/
public class UserDAOImpl extends BaseDAOHibernateImpl 2T@GA1G
kd`0E-QU
implements UserDAO { im7nJQ^H$q
}v9\F-0>Q
/* (non-Javadoc) 1=sXdcy;
* @see com.adt.dao.UserDAO#getUserByName Q5{Pv}Jx
}?F`t[+
(java.lang.String) '^BV_ QQ
*/ !Z!g:II
/
publicList getUserByName(String name)throws mR\`DltoV
\0l>q ,
HibernateException { PNF?;*`-{7
String querySentence = "FROM user in class SzwQOs*
s>k Uh
com.adt.po.User WHERE user.name=:name"; 7|\@zQ h
Query query = getSession().createQuery `\`> 0hlu
*L6PLe
(querySentence); n79QJl/
query.setParameter("name", name); ;8WZx
return query.list(); T{qTj6I
} w=]Ks'C]
%W,D;?lEo>
/* (non-Javadoc) <~TP#uAz
* @see com.adt.dao.UserDAO#getUserCount() pLa[}=
*/ '{I_\~*
publicint getUserCount()throws HibernateException { =deMd`=J
int count = 0; TD[EQ
String querySentence = "SELECT count(*) FROM YjF|XPv+ l
|7,L`utp
user in class com.adt.po.User"; _=ua6}Xp
Query query = getSession().createQuery 9Zry]$0~R
NN0$}ac p
(querySentence); Uoya3#4 G
count = ((Integer)query.iterate().next <IW#ME
D jk C
()).intValue(); Uz cx6sw
return count; 2%*MW"Q
} {oc igR0
E$9Ys
/* (non-Javadoc) t?o,RN:
* @see com.adt.dao.UserDAO#getUserByPage c_aZ{S
5D M"0
(org.flyware.util.page.Page) -9RDr\&`(
*/ g%F"l2M
publicList getUserByPage(Page page)throws g(VNy@
0;S, tJg
HibernateException { %ms'n
String querySentence = "FROM user in class Wg{k$T_>
M8H5K
com.adt.po.User"; }N_NvY
Query query = getSession().createQuery lo%;aK
AL$&|=C-$
(querySentence); izh<I0
query.setFirstResult(page.getBeginIndex()) *Av"JAX
.setMaxResults(page.getEveryPage()); &g2 Eptx#
return query.list(); G}5 #l
} M"%Q&o/I
zR!o{8
} z
<mK>$
KH\b_>wU2
&//wSlL3
n JPyM/p
{t};-q!v$j
至此,一个完整的分页程序完成。前台的只需要调用 qE'9QQ>:b
dKl^jsd
userManager.listUser(page)即可得到一个Page对象和结果集对象 hTP:[w)
6wco&7
的综合体,而传入的参数page对象则可以由前台传入,如果用
h:lt<y
]Jh+'RK\#
webwork,甚至可以直接在配置文件中指定。 1ygpp0IGJ
QwhRNnE=
下面给出一个webwork调用示例: PoEqurH0
java代码: r=yK,d/1
AiD[SR
jx acg^c
/*Created on 2005-6-17*/ v]__%_
package com.adt.action.user; ?+T^O?r|O
\{Q?^E
import java.util.List; S+TOSjfis
\om%Q[F7a
import org.apache.commons.logging.Log; nG_6oe*=I
import org.apache.commons.logging.LogFactory; =^H4 Yck/5
import org.flyware.util.page.Page; eZ"1gYqy
cyxuK*x<
import com.adt.bo.Result; E}%hz*Q)(
import com.adt.service.UserService; 5[j`6l
import com.opensymphony.xwork.Action; T~h5B(J;
JCAq8=zM
/** <~
J O
s2
* @author Joa 3\T2?w9u(
*/ (KvROV);
publicclass ListUser implementsAction{ g$.
\
@( n^T
privatestaticfinal Log logger = LogFactory.getLog Ltjbxw"Qd
`jS T
(ListUser.class); bc
, p}
D&HV6#
private UserService userService; i#%aTRKHd6
s1?[7yC
private Page page; p4p@^@<>X
~b{Gz6u>
privateList users; m Sk5u 7
lO2[JP
/* E^U0f/5
m
* (non-Javadoc) xkOpa,=FI
* y4+;z2'>
* @see com.opensymphony.xwork.Action#execute() RpLE
02U
*/ Lg"C ]
publicString execute()throwsException{ e.c3nKXZ q
Result result = userService.listUser(page); KR7@[
page = result.getPage(); mo~*C
users = result.getContent(); p }[zt#v
return SUCCESS; =IAsH85Q
} qY 4#V k
$=?@*p
/** Ts~L:3oaQ
* @return Returns the page. $ cj>2.
*/ `K,1K
public Page getPage(){ nC{%quwh{
return page; Zw
wqSyuGf
} ^&g=u5
d0
Fs[aa#v4B
/** &~CY]PN.
* @return Returns the users. ]
}f9JNf$
*/ Pz$R(TV
publicList getUsers(){ y\{%\ $
return users; ax
41N25
} DNP13wp@
C*nB
/** }MUn/ [x
* @param page gk`zA
* The page to set. Z4IgBn(Z_}
*/ '=P7""mN5
publicvoid setPage(Page page){ %,ngRYxT#
this.page = page; Le%ZV%,
} F: mq'<Q
-.{g}R%
/** ;2Q~0a|
* @param users vX ] Gf4,
* The users to set. ytNO*XoR
*/ Fv<`AU
publicvoid setUsers(List users){ r1fGJv1!o
this.users = users; B7]MGXC
} P'Q+GRpSw
/rSH"$
/** Ks}Xgc\
* @param userService ,-z9 #t
* The userService to set. KF4PJi;*
*/ ^wS5>lf7p
publicvoid setUserService(UserService userService){ Is+O
this.userService = userService; N!`e}Z6S
} 0?>dCu\
} c&L"N!4z
d:yqj:
~Ch+5A;
NzNA>[$[
aN(|'uO@
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, qoAj]
")
`mN4_\]
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 \rPbK+G.
O(_[ayE
么只需要: |hr]>P1
java代码: (e"iO`H
K(q-?n`<
H'HSD,>(
<?xml version="1.0"?> U#U]Pt
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork SB)5@
nmS
9Vf1Xz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- qpXWi
&g
0
Us5
1.0.dtd"> Qqlup
cYqfsd# B
<xwork> ,*7d
-ig6w.%lk
<package name="user" extends="webwork- _2N$LLbg
D1&A,2wO
interceptors"> g(4xC7xK6
1T[et-
<!-- The default interceptor stack name Y/7 $1k
H@l}WihW
--> gynh#&r
<default-interceptor-ref uIZWO.OdU
!A%<#Gjt
name="myDefaultWebStack"/> rylzcN9RM$
ciMzf$+G$
<action name="listUser" \G-KplKS
&~W:xg(jN
class="com.adt.action.user.ListUser"> cH>%r^G\
<param l<N}!lG|
O|w J)
name="page.everyPage">10</param> KIWe@e
<result ;amXY@RmH
w}=5ElB
name="success">/user/user_list.jsp</result> !o$!Fr c
</action> aE2.L;Tk?
M|Rb&6O
</package> x*/S*!vx\
^_m9KA
</xwork> YY!Rz[/
]KmO$4
"&3h2(#%
~
yX2\i"
&?(?vDFfZ
+>PX&F
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 6:~v4W!k
=W'Ae,&
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 r-<F5<H+K@
IC7M$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 [Vma^B$7Vj
qT^I?g"!
Ng_!zrx04
)Eo)t>
rvw)-=qR[
我写的一个用于分页的类,用了泛型了,hoho `*shF9.\C
:ijAqfX
java代码: Gy(=706
87YyDWTn
)+6MK(<"
package com.intokr.util; )-._FOZ6
=&:Y6XP
import java.util.List; Ywwu0.H<
' <=+;q
/** wH@Ns~[MA
* 用于分页的类<br> :eCU/BC4
* 可以用于传递查询的结果也可以用于传送查询的参数<br> y~\oTJb
* Nal9M[]c
* @version 0.01 a0#J9O_
* @author cheng Ct>GYk$
*/ UNBH
public class Paginator<E> { mrjswF27$o
privateint count = 0; // 总记录数 V=*wKuB
privateint p = 1; // 页编号 <Sr
privateint num = 20; // 每页的记录数 [)TRTxFb
privateList<E> results = null; // 结果 .Fp4:
e
N}t
2Nu-
/** \7'+h5a
* 结果总数 t)}scf&^x
*/ ;-qO'V:;
publicint getCount(){ .P"D
return count; c(~[$)i6
} T]c%!&^_
5wDg'X]>V
publicvoid setCount(int count){ XD2v*l|Po
this.count = count; Kuu *&u
} WA&!;Zq
#NryLE!/
/** bXNk%W[n
* 本结果所在的页码,从1开始 {Sj9%2'M)
* (:>,u*x%
* @return Returns the pageNo. Bn &Ws
*/ q1KZ5G)6GJ
publicint getP(){ 736Jq^T
return p; k5kxQhPf
} |0f>aZ
e-EUf
/** D1=((`v
'
* if(p<=0) p=1 mUikA9u5=
* "LlfOKG
* @param p P`cq H(
*/ ?BZ PwGMs
publicvoid setP(int p){ I<6P;
if(p <= 0) ~G6Ox)/
p = 1; @pRlxkvV
this.p = p; ] [p>Y>:b-
} ~XmLX)vO/
GVYkJ0,
/** R1$:~p2m
* 每页记录数量
t!_<~
*/
ElW~48
publicint getNum(){ |}di&y@-JI
return num; v: OR
} F}/S:(6LF2
o9dY9o+Z
/** '$ t
* if(num<1) num=1 I!Z_[M
*/ /Y2}a<3&0
publicvoid setNum(int num){ U ^5Kz-5.
if(num < 1) _ =VqrK7T
num = 1; vkEiOFU!u
this.num = num; LoN< oj5
} T~##,qQ
;"~
fZ2$U
/** x#xFh0CA
* 获得总页数 ?WqT[MnK
*/ /n{omx
publicint getPageNum(){ #PH~1`vl
return(count - 1) / num + 1; SPY|K
} ORJIo
mQ|v26R
/** !u[eaLxV
* 获得本页的开始编号,为 (p-1)*num+1 +b3RkkC
*/ &&8IU;J
publicint getStart(){ `n@*{J8
return(p - 1) * num + 1; 6"J?
#
} ijK"^4i
<(fRn`)PT
/** R?"q]af~
* @return Returns the results. SVh 7zh
*/
\kMefU
publicList<E> getResults(){ !W}9no
return results; zkuU5O
} eo?;`7
o.!~8mD
public void setResults(List<E> results){ 7`zHX&-W
this.results = results; ?IqQ-C)6D
} pS'FI@.'{
Y4`}y-'d
public String toString(){ Tz8PS k1[
StringBuilder buff = new StringBuilder v50bdj9}k
PGhY>$q>b
(); bB1UZ O
buff.append("{"); )f[
B6Y
buff.append("count:").append(count); 2a`o
&S
buff.append(",p:").append(p); L\xk:j1[
buff.append(",nump:").append(num); Ez
fN&8E
buff.append(",results:").append vyK7I%T'R
Ybs\ES'?A
(results); >_-s8t=|
buff.append("}"); zuJ@E=7
return buff.toString(); KWowN;
} e478U$
>>t@}F)
} `(ue63AZ
~obqG!2m
"$+Jnc!!