Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 8v']>5S]#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 o*1t)HL <
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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 k0R;1lZ0n
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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 =v]eQIp
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分页支持类: hX@.k|Yd
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java代码: B^G{k3]t
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package com.javaeye.common.util; #]5|Qhrr+
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import java.util.List; yi/jZX
i iZK^/P$
publicclass PaginationSupport { Q{Lsr,
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publicfinalstaticint PAGESIZE = 30; dSBW&-p
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privateint pageSize = PAGESIZE; ?OPAf4h
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privateList items; _;+N=/l0
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privateint totalCount; 0IEFCDeCO
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privateint[] indexes = newint[0]; <U$A_]*w
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privateint startIndex = 0; nNff~u)I
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public PaginationSupport(List items, int v#`Wf}G
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totalCount){ o s
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setPageSize(PAGESIZE); /Iu._2
setTotalCount(totalCount); jq&$YmWp
setItems(items); =}~hbPJM
setStartIndex(0); kM?p >V6
} S,,3h0$X
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public PaginationSupport(List items, int U;:,$]+
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totalCount, int startIndex){ YA>du=6y\
setPageSize(PAGESIZE); `$\Y,9E}x
setTotalCount(totalCount); ;pNHT*>u,
setItems(items); $|YIr7?R
setStartIndex(startIndex); _k@{>
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} Wwf#PcC]
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public PaginationSupport(List items, int Yn}_"FO'
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totalCount, int pageSize, int startIndex){ VBssn]w
setPageSize(pageSize); 3EcmNwr
setTotalCount(totalCount); <z|? C
setItems(items); G?]E6R
setStartIndex(startIndex); EhybaRy;C
} q'?:{k$%
hqY9\,.C
publicList getItems(){ (K+TqJw
return items; MNiu5-g5
} sHrpBm&O4
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publicvoid setItems(List items){ Tf"DpA!_
this.items = items; >M^
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} wDZFOx0#8
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publicint getPageSize(){ q$`:/ ehw
return pageSize; LxVd7r VY6
} ?Y'S
/
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publicvoid setPageSize(int pageSize){ ZjEO$ts=@
this.pageSize = pageSize; 5
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} B<[;rk
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publicint getTotalCount(){ asW1GZO
return totalCount; FV$= l
%
} S_:(I^
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publicvoid setTotalCount(int totalCount){ ooIMN =
if(totalCount > 0){ >UJ&noUD#:
this.totalCount = totalCount; ),\>'{~5&
int count = totalCount / 1qUdj[Bj
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pageSize; FzpWT-jnDd
if(totalCount % pageSize > 0) 0mj=\ j
count++; i:kWO7aP
indexes = newint[count]; nHKEtKDd
for(int i = 0; i < count; i++){ 0m`7|80#P
indexes = pageSize * 7"xd'\c@
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i; n/?5[O-D]
} 5.[{PJ]bq
}else{ 2,&lGyV#
this.totalCount = 0; cJ8F#t
} vo`wYJ3W
} fsjA7)/
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publicint[] getIndexes(){ *-|+phim
return indexes; ]QT0sGl
} ;*W]]4fy
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publicvoid setIndexes(int[] indexes){ g@Ni!U"_c
this.indexes = indexes; /"CKVQ
} HxY,R^
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publicint getStartIndex(){ .4!N#'
return startIndex; F` I-G~e
} r$v?[x>+K
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publicvoid setStartIndex(int startIndex){ ;wQWt_OtuJ
if(totalCount <= 0) F41!Dj7
this.startIndex = 0; P1)
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elseif(startIndex >= totalCount) _;B!6cRLps
this.startIndex = indexes 29sgi"
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[indexes.length - 1]; 3^Yk?kFE
elseif(startIndex < 0) \;7DS:d@
this.startIndex = 0; FOk @W&
else{ M+hc,;6
this.startIndex = indexes jq0tMTb%L
0"2 [I
[startIndex / pageSize]; NNl/'ge<\
} M@'V4oUz
} (C-z8R
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publicint getNextIndex(){ &YT7>z,
int nextIndex = getStartIndex() + Bd
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pageSize; =|U2 }U;
if(nextIndex >= totalCount) p fBO5Ys
return getStartIndex(); _kY5
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else zi?'3T%Ie
return nextIndex; ^CK)q2K>[
} J.<%E[
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publicint getPreviousIndex(){ 6ZG)`u".("
int previousIndex = getStartIndex() - K<]fElh-
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pageSize; .897Z|$VB
if(previousIndex < 0) xu:m~8%
return0; g
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else #h3+T*5} 6
return previousIndex; 4{vd6T}V!
} \PLV]%3,
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} b<F 4_WF
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抽象业务类 ,g,jY]o
java代码: @zJI0_Bp
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/** k(
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* Created on 2005-7-12 <y.D0^68
*/ "q`%d_
package com.javaeye.common.business; i9xv`Ev=R
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import java.io.Serializable; AltE~D/4
import java.util.List; R82Y&s;
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import org.hibernate.Criteria; fjWh}w8
import org.hibernate.HibernateException; gNqV>p
import org.hibernate.Session; vfv5ex(
import org.hibernate.criterion.DetachedCriteria; '.K,EM!-~h
import org.hibernate.criterion.Projections; Wl#^Eu\g1W
import 0&.lSwa
q9
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org.springframework.orm.hibernate3.HibernateCallback; xF/D YXC{8
import .HQ<6k:
og\XLJ}_
org.springframework.orm.hibernate3.support.HibernateDaoS ltrSTH,kL
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upport; WvJ?e
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import com.javaeye.common.util.PaginationSupport; pMB=iS<E
7P`1)juA9
public abstract class AbstractManager extends (Z$6JNkz
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HibernateDaoSupport { 2:N_c\Vi
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privateboolean cacheQueries = false; qE{cCS
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privateString queryCacheRegion; 'i(p@m<'
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publicvoid setCacheQueries(boolean ?8, N4T0)
@
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cacheQueries){ 'sF563kE
this.cacheQueries = cacheQueries; U]D.z}0
} K%}I}8M
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publicvoid setQueryCacheRegion(String =|!~0O
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queryCacheRegion){ NNE,|
:
this.queryCacheRegion = -{*V)J_Co
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queryCacheRegion; /a(zLHyz)
} e\_6/j7'
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publicvoid save(finalObject entity){ .V3Dql@z"
getHibernateTemplate().save(entity); be/1-=m
} n`}&,UA$4
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publicvoid persist(finalObject entity){ Mak9qaWqF>
getHibernateTemplate().save(entity); BZ<z@DJp
} GzXP
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publicvoid update(finalObject entity){ `fkrik
getHibernateTemplate().update(entity); na3kHx@
} @L!#i*> 9
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publicvoid delete(finalObject entity){ JYr7;n'!
getHibernateTemplate().delete(entity); }AiS83B
} YhT1P fl
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publicObject load(finalClass entity, VQ?H:1R
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finalSerializable id){ 9(F?|bfk
return getHibernateTemplate().load ZY!pw6R1>*
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(entity, id); 1:!rw,Jzl`
} R$fIb}PDr
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publicObject get(finalClass entity, (bt]GAxb1
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finalSerializable id){ $JB:rozE
return getHibernateTemplate().get C5 5n
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(entity, id); ]0i2]=J&,
} pmyM&'#Id
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publicList findAll(finalClass entity){ c'+r[rSn1
return getHibernateTemplate().find("from ;]M67ma7C
ba9<(0`
" + entity.getName()); 1ysLZ;K
} ]XGn2U\
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publicList findByNamedQuery(finalString OPY/XKyY,
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namedQuery){ ]2Fo.n
return getHibernateTemplate FFeRE{,
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().findByNamedQuery(namedQuery); j' *p
} [E~,> Q
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publicList findByNamedQuery(finalString query, x0A%kp&w
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finalObject parameter){ a61eH )a
return getHibernateTemplate {qWG^Db
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().findByNamedQuery(query, parameter); quGPk)c
} LEngZ~sV/
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publicList findByNamedQuery(finalString query, v~2XGm
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finalObject[] parameters){ 4`-?r%$,:
return getHibernateTemplate 31sgf5 s
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().findByNamedQuery(query, parameters); ;k&k#>L!K
} #Wm@&|U
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publicList find(finalString query){ vx5o
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return getHibernateTemplate().find _{`'{u
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(query); NVA`t]gn
}
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publicList find(finalString query, finalObject 0"<;You
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parameter){ CAFE}|
return getHibernateTemplate().find aH PSnB&
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(query, parameter); ,6orB}w?z
} Sp~Gv>uMK
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public PaginationSupport findPageByCriteria
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=7]Q6h@X
(final DetachedCriteria detachedCriteria){ aBVEk2 p
return findPageByCriteria %QsSR'`
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); X\^& nLa
} svq9@!go
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public PaginationSupport findPageByCriteria k`7.p,;}U
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(final DetachedCriteria detachedCriteria, finalint R3{*v =ov
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startIndex){ rxgVT4
return findPageByCriteria [rUh;_b\D
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(detachedCriteria, PaginationSupport.PAGESIZE, }u3H4S<o
L >Ez-
startIndex); spU!t-n67
} itC *Z6^
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public PaginationSupport findPageByCriteria hKH$AEHEU}
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(final DetachedCriteria detachedCriteria, finalint Q 9gFTLQ
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pageSize, 4j@kMe;RjZ
finalint startIndex){ _> |R-vQ8
return(PaginationSupport) [zh4W*K_cq
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getHibernateTemplate().execute(new HibernateCallback(){ nT@6g|!
publicObject doInHibernate 43u PH1
)
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(Session session)throws HibernateException { FU(}=5n
Criteria criteria = K?FX<PT
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detachedCriteria.getExecutableCriteria(session); JhhUg
int totalCount = +Jo 3rX'`
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((Integer) criteria.setProjection(Projections.rowCount '?`@7Eol
ET,0ux9F
()).uniqueResult()).intValue(); e\^g|60f_
criteria.setProjection w]W`R.
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(null); u8<&F`7j
List items = ;*wT,2;
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criteria.setFirstResult(startIndex).setMaxResults n?ZL"!$
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(pageSize).list(); ]{Mci]H6T
PaginationSupport ps = <uBhi4
#Cg}!38
new PaginationSupport(items, totalCount, pageSize, +#-kIaU
^&`sWO@=
startIndex); *;OJ~zT
return ps; [V> :`?
} )p/=u@8_f
}, true); 3WO#^}t
} t?]\M&i&
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public List findAllByCriteria(final 6Q.{llO
r
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DetachedCriteria detachedCriteria){ l50|`
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return(List) getHibernateTemplate !"`@sd~
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().execute(new HibernateCallback(){ RjR&D?dc
publicObject doInHibernate %k3NT~
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(Session session)throws HibernateException { /RJ6nmN@}
Criteria criteria = cX|[WT0[I
.%x"t>]
detachedCriteria.getExecutableCriteria(session); ;NiArcAS!
return criteria.list(); W"b&M%y|
} QMXD9H0{
}, true); *Fa)\.XX
} )K>Eniou
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public int getCountByCriteria(final "8wf.nZ
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DetachedCriteria detachedCriteria){ =~GE?}.o
Integer count = (Integer) yCF"Z/.
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getHibernateTemplate().execute(new HibernateCallback(){ TIcd
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publicObject doInHibernate a)3O? Y
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(Session session)throws HibernateException { _o@(wGeu#
Criteria criteria = G$?|S@I,
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detachedCriteria.getExecutableCriteria(session); ~q0I7M
return [,OJX
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criteria.setProjection(Projections.rowCount 'GEBxNH:
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()).uniqueResult(); Qqd6.F
} Yw$a{5g
}, true); {l&Ltruhz
return count.intValue(); 82j'MgGP
} (Oxz'#TX
} A[u)wX^`f^
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用户在web层构造查询条件detachedCriteria,和可选的 [<]Y+33
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <U@P=G<t
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PaginationSupport的实例ps。 Sg-g^dIN1
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ps.getItems()得到已分页好的结果集 z=ML(1c=
ps.getIndexes()得到分页索引的数组 T?W[Z_D
ps.getTotalCount()得到总结果数 ( MB`hk-d
ps.getStartIndex()当前分页索引 M
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ps.getNextIndex()下一页索引 PV?]UUc'n<
ps.getPreviousIndex()上一页索引 m! rwG(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错
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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 :ar?0
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一下代码重构了。 HbNYP/MN3
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我把原本我的做法也提供出来供大家讨论吧: +IG1IF
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首先,为了实现分页查询,我封装了一个Page类: }0$mn)*k
java代码: 3>i>@n_
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/*Created on 2005-4-14*/ Yx6hA#7I
package org.flyware.util.page; ]\OWZ{T'j
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/** 3@&bxYXm
* @author Joa o>2e!7
* |</"N-#S
*/ 6G'<[gL
j
publicclass Page { 'g]hmE
IQT cYl
/** imply if the page has previous page */ Yy]T
J
privateboolean hasPrePage; :v`o6x8
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/** imply if the page has next page */ SC'BmR"ox
privateboolean hasNextPage; ^Z2kq2}a
, 7Xqte
/** the number of every page */ *9J1$Wa
privateint everyPage; hL0]R,t;'
(zY * 0lN
/** the total page number */ ,~- ?l7
privateint totalPage; v51EXf
oAY_sg+
/** the number of current page */ W}>=JoN^J
privateint currentPage; ~wTX>qV
/KAlK5<
/** the begin index of the records by the current ^;zWWg/d
" \:ced
query */ *xcP`
privateint beginIndex; ;W0]66&
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/** The default constructor */ _S"f_W
public Page(){ 71O3O7
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} NY@"&p'Q
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/** construct the page by everyPage j5\$[-';
* @param everyPage \X&
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* */ u?kD)5Nk
public Page(int everyPage){ rs:Q%V
^
this.everyPage = everyPage; a=+T95ulDy
} khAqYu")
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/** The whole constructor */ noC?k }M
public Page(boolean hasPrePage, boolean hasNextPage, ^YKy9zkTl
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int everyPage, int totalPage, (S oo<.9~
int currentPage, int beginIndex){ H0a-(
this.hasPrePage = hasPrePage; =Y9\DeIZ
this.hasNextPage = hasNextPage; pcH<gF(k
this.everyPage = everyPage; 'S?;J ,/
this.totalPage = totalPage; ID4~Gn
this.currentPage = currentPage; ^Dr.DWi{$
this.beginIndex = beginIndex; ,GrB'N{8e
} cx^{/U?9}
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/** Pr+~Kif
* @return C c*({
* Returns the beginIndex. HR60
*/ ;LRW
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publicint getBeginIndex(){ M$A#I51
return beginIndex; iCTQ]H3
} 7yI`e*EOD
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/** =-~;OH/
* @param beginIndex cS|VJWgTZ
* The beginIndex to set. i-W
*/ '# z]M
publicvoid setBeginIndex(int beginIndex){ |;u}sX1t9
this.beginIndex = beginIndex; s-k_d<
} kq-6HDR
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/** 5)'P'kVi7.
* @return o2=A0ogz?
* Returns the currentPage. -[R!O'N9
*/ =MLf[
publicint getCurrentPage(){ XoR>H4xh
return currentPage; \k@Z7+&7
} dB;3.<S=
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/** xd8
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* @param currentPage )ofm_R'q*
* The currentPage to set. #tjmWGo,
*/ t`G)b&3_O
publicvoid setCurrentPage(int currentPage){ o>c^aRZ{
this.currentPage = currentPage; #SkX@sl@
} 8g*hvPc
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/** Ht[{ryTxu
* @return Dag`>|my
* Returns the everyPage. aMK~1]Cx
*/ G>
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publicint getEveryPage(){ LdTdQ,s<
return everyPage; wAYB RY[
} C+%K6/J(
lKKERO5+
/** 'r+PH*Mr
* @param everyPage KJh,,xI>by
* The everyPage to set. mm[SBiFO\
*/ dDtFx2(R
publicvoid setEveryPage(int everyPage){ 7=P^_LcU
this.everyPage = everyPage; t`|,6qEG
} V U~Dk);Bv
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/** "0&N}
* @return G'x .NL
* Returns the hasNextPage. E\{< ;S
*/ vR>o}%`
publicboolean getHasNextPage(){ pOga6'aB)
return hasNextPage; H4<Nnd\
} C!%:o/
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/** XU-m"_t
* @param hasNextPage K: r\{#9
* The hasNextPage to set. 8`v$liH
*/ H?yE3w
publicvoid setHasNextPage(boolean hasNextPage){ Q:MhjkOr}
this.hasNextPage = hasNextPage; kzO&24
} Tby,J
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/** F}X0',
* @return RuAlB*
* Returns the hasPrePage. Kt/)pc
*/ AQ{zx1^2>K
publicboolean getHasPrePage(){ V#83!
return hasPrePage; !.Zt[ g}
} @CQb[!9C
rdJB*Rlkh
/** 5bX6#5uP1
* @param hasPrePage G&9#*<F$c
* The hasPrePage to set. I&]G
*/ X-JV'KE}^z
publicvoid setHasPrePage(boolean hasPrePage){ w1|Hy2D`0
this.hasPrePage = hasPrePage; MZv\ C
} i$UQbd
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/** {3edTu
* @return Returns the totalPage. .~klG&>aV
* c[cAUsk i
*/ :q+N&j'3
publicint getTotalPage(){ uS5o?fg\e
return totalPage; j9y3hQ+q
} Fu _@!K
#a9_~\s
/** |3eGz%Sd
* @param totalPage OX hAha`R
* The totalPage to set. TbhH&kG)1
*/ ;+Yi.Q/\
publicvoid setTotalPage(int totalPage){ MagMZR
this.totalPage = totalPage; 7_\Mwy{P
} g+[kde;(^
kv?|'DN
} -{g~TUz
<GIwRVCU
raB+,Oi$G
83iCL; GS=
cFZCf8:zB
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 %3=J*wj>D
NHaMo*xQ
个PageUtil,负责对Page对象进行构造: K"{HseN{
java代码: RKkGITDk
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/*Created on 2005-4-14*/ pY}/j;.[
package org.flyware.util.page; U;^[$Aq
)0CQP
import org.apache.commons.logging.Log; H;KDZO9W
import org.apache.commons.logging.LogFactory; 1dG06<!
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/** yTAvF\s$(
* @author Joa hWEnn=BW
* H{`{)mS
*/ (Mt5 P
publicclass PageUtil { w:ULi3
1B:aC|B
privatestaticfinal Log logger = LogFactory.getLog O!R"v'
w2"]Pl
(PageUtil.class); -- k:a$Nt
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/** Tz-X o
* Use the origin page to create a new page 2qj{n+
* @param page V[hK2rVH.
* @param totalRecords \,xFg w4
* @return m *X7T
*/ t/p $
publicstatic Page createPage(Page page, int 1~5trsB+5
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totalRecords){ Omyt2`q
return createPage(page.getEveryPage(), IF_D Z
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page.getCurrentPage(), totalRecords); k DsIp=
} Tj`5L6N;8
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/** S`q%ypy
* the basic page utils not including exception " 'tRfB
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handler SN">gmY+
* @param everyPage vA&Vu"}S
* @param currentPage ;5S}~+j
* @param totalRecords 9'KonW
* @return page (H#M<N
*/ +1`t}hO
publicstatic Page createPage(int everyPage, int 9`Q@'(m
Wk7WK` >i
currentPage, int totalRecords){ #G;X' BN
everyPage = getEveryPage(everyPage); q~Jq/E"f
currentPage = getCurrentPage(currentPage); BGWAh2w6
int beginIndex = getBeginIndex(everyPage, n9UKcN-
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currentPage); X;GfPw.m
int totalPage = getTotalPage(everyPage, !~ rt:Z
4u1KF:g
totalRecords); sa#.l% #
boolean hasNextPage = hasNextPage(currentPage, %u!XzdG
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totalPage); a W;aA'!
boolean hasPrePage = hasPrePage(currentPage); !{%G0(Dv
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returnnew Page(hasPrePage, hasNextPage, Q< *8<Oo4g
everyPage, totalPage, vq6%Ey3Gix
currentPage, ?y%t}C\W
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K<
beginIndex); 8A2z 5Aa
} ">90E^
t1i(;|8|
privatestaticint getEveryPage(int everyPage){ [xaisXvI4
return everyPage == 0 ? 10 : everyPage; AtHS@p
} uofLhy!
f(Hu {c5yV
privatestaticint getCurrentPage(int currentPage){ j}WByaZ&
return currentPage == 0 ? 1 : currentPage; h4`9Cfrq ,
} tYe:z:7l?<
!]b@RUU
privatestaticint getBeginIndex(int everyPage, int L*
|1/
$@uU@fLB
currentPage){ (6qsKX
return(currentPage - 1) * everyPage; f&I7,"v
} @.$MzPQQI
);JJ2Jlkd
privatestaticint getTotalPage(int everyPage, int TSto9$}*
.[j%sGdKl
totalRecords){ v '9m7$
int totalPage = 0; AK/:I>M
wK*PD&nN
if(totalRecords % everyPage == 0) 5
2Hqu>
totalPage = totalRecords / everyPage; v\A.Tyy
else R@`rT*lJ
totalPage = totalRecords / everyPage + 1 ; z+VV}:Q
&8?`<
return totalPage; Spj9H ?m
} kQIw/@WC
IN !02`H
privatestaticboolean hasPrePage(int currentPage){ OyVm(%Z
return currentPage == 1 ? false : true; b X,Siz:F
} l)|lTOjb
>&K!VQ{g
privatestaticboolean hasNextPage(int currentPage, 5h^[^*A?
ti_u!kNv
int totalPage){ bkv/I{C>?
return currentPage == totalPage || totalPage == \ TL82H@D
k0ItG?Cv
0 ? false : true; *\ECf.7jz
} YoSQN/Z
!,bPe5?Ql
&]NZvqdj.]
} 36A;!1
EXbTCT}`x
p\D >z("
V
SAafux
=vEkMJOs
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。 Zu#<
Ay$>(;
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 u,9q<&,
lB:l)!]||=
做法如下: Y5%;p33uFG
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }$aNOf%:
A*0*sZ0
的信息,和一个结果集List: p24.bLr
java代码: e'~ Q@_D
pxplWP,
HdCk!Fv
/*Created on 2005-6-13*/ s[V`e2O
package com.adt.bo; l,y^HTc}7/
x0G>ktWq<
import java.util.List; JlIS0hnv
vttrKVA
import org.flyware.util.page.Page; _rjBc;a
%b<%w
/** Zi1YZxF`Y
* @author Joa AbY;H
*/ a4by^
publicclass Result { WZ*&@|w
Sx&mv.?X
private Page page; :ICr\FY$
gb-tNhJa@b
private List content; sU%"azc
eH[y[~r
/** fsI`DjKi)
* The default constructor .@K#U52
*/ /(zB0TEd
public Result(){ D_ ug-<QT
super(); 3"tg+DncC
} 3-
)kwy6L
8IOj[&%0
/** B;c=eMw
* The constructor using fields *vs~SzF$
* +Ag#B*
* @param page k2uBaj]
* @param content t>oM%/H
*/
5KaSWw/
public Result(Page page, List content){ 9|a)sb7/
this.page = page; $4h04_"
this.content = content; ~UW{)]_jox
} R `Q?J[e
Eq7gcDQ
/** P^;WB*V
* @return Returns the content. Z@nmjj i
*/ B>aEHb
publicList getContent(){ p[gAZ9
return content; 2K~tDNv7
} c}\
d5R_L
0gi}"v
/** 2dyxKK!\a
* @return Returns the page. _<Vg[-:1
*/ b)y<.pS\
public Page getPage(){ {4)5]62>u
return page; :z124Zf
} WiwwCKjSa
i*b4uHna
/** NIL^UN}
* @param content 10TSc
j
* The content to set. bY&YSlO
*/ `7$Oh{67
public void setContent(List content){
,gx$U@0Z
this.content = content; I')x]edU
} MIJ%_=sm4:
ls]Elo8h1f
/** -KA4Inn]5
* @param page +@ ^47Xu^
* The page to set. BiI{8`M!$x
*/ B~e7w 4
publicvoid setPage(Page page){ su%Z{f)#
this.page = page; _"`uqW79
} Z#[>N,P
} v@]6<e$
uvNnW}G4
H|x k${R`
W *|OOa'
Je@p5(f
2. 编写业务逻辑接口,并实现它(UserManager, s}<)BRZi
B##C{^5A`
UserManagerImpl) P'gT6*an,"
java代码: <"{+
5auL<Pq
}]Qmt5'NI
/*Created on 2005-7-15*/ }%
FDm@+
package com.adt.service; bmSpbX\
<w%Yq?^
import net.sf.hibernate.HibernateException; >n#g9v K
FC~|&
import org.flyware.util.page.Page; 18J.vcP
2>`m<&y
import com.adt.bo.Result; ^glbxbhI4
M_|M&lR>
/** )moo?Q
* @author Joa Py}!C@e
*/ \qRjXadj
publicinterface UserManager { nqUH6(
B/:>{2cm
public Result listUser(Page page)throws 0 [*nAo
-aTg>Q|g&
HibernateException; a [0N,t
OME!W w
} #a/n5c&6/
G >I.
dawVE
O
5Q2TT $P
z2"2tFK
java代码: W8\PCXnsfl
3T Yo
xuw//F
/*Created on 2005-7-15*/ *#3voJjV(
package com.adt.service.impl; ^Osd/g
$#g#[/
import java.util.List; l;.[W|
G}Q}H*
import net.sf.hibernate.HibernateException; ~Q3WBOjn
}6yxt9
import org.flyware.util.page.Page; #J'Z5)i|
import org.flyware.util.page.PageUtil; }39M_4a&
(e>RNn\
import com.adt.bo.Result; P6.) P|n7=
import com.adt.dao.UserDAO; 1e+h9|hGYw
import com.adt.exception.ObjectNotFoundException; 0Ax>gj-`
import com.adt.service.UserManager; Hz8Jgp
rjhs?
/** 'Y,+D`&i)
* @author Joa )< X=z
*/ PxdJOtI"
publicclass UserManagerImpl implements UserManager { ft*G*.0kO
>'BU*
private UserDAO userDAO; sPZV>Q:zY
IIYX|;1}X
/** nvm1.}=Cnd
* @param userDAO The userDAO to set. ZlwcwoPib
*/ /zDSlj<c
publicvoid setUserDAO(UserDAO userDAO){ YA1{-7'Q
this.userDAO = userDAO; }0(vR_x
} N6-2*ES
Ae,2Xi
/* (non-Javadoc) }bj,&c
* @see com.adt.service.UserManager#listUser )w3XN A_V
i2\\!s
(org.flyware.util.page.Page) :BC<+T=
*/ z22|Kv;w
public Result listUser(Page page)throws 2-
|j
zEA{%)W
HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); h|$zHm
if(totalRecords == 0) & y 2GQJE
throw new ObjectNotFoundException }lrfO_
~CjmYP'o
("userNotExist"); o} bj!h]N
page = PageUtil.createPage(page, totalRecords); #I*ht0++
List users = userDAO.getUserByPage(page); q=j/s4~
returnnew Result(page, users); Xs#?~~"aC
} */fs.G:P
v/4X[6(
} E Ni%ge'":
ijR*5#5h
bb0{-T)1
?U2g8D nFY
{H"=PYR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ivDG3>"JG
4G68WBT
询,接下来编写UserDAO的代码: &].1[&M]
3. UserDAO 和 UserDAOImpl: =Un 6|]
java代码: &<[]X@ bY
qjdahVY
cl9;2D"Zm!
/*Created on 2005-7-15*/ 5y
'ycTjY
package com.adt.dao; oM?
C62g\
Fg}5V,
import java.util.List; FB^dp}
7\|NYT4
import org.flyware.util.page.Page; y:(C=*^<t
}lQn]q
import net.sf.hibernate.HibernateException; u3ri6Y`
wft:eQ
/** a 7mKshY(
* @author Joa PPIG?fK)
*/ P^d.,
publicinterface UserDAO extends BaseDAO { lk *QV
+{l3#Y
publicList getUserByName(String name)throws #,|_d>p:
>GF(.:7
HibernateException; tz \:r>3vI
z2EI"'4\9
publicint getUserCount()throws HibernateException; E6KBpQcd[
5{x[EXE'
publicList getUserByPage(Page page)throws +T8XX@#
#Z3I%bkw H
HibernateException; IWbp^l+!t
k)4lX|}Vm
} ";!1(xZr
c )P%O
e"&9G}.f
2l}FgD
3dzqVaV
java代码: /`]|_>'
KE|u}M@v6
Z+pvdu
/*Created on 2005-7-15*/ n46PQm%p
package com.adt.dao.impl; .4m3@!qo)E
)]e d;V
import java.util.List; 5|B(K @<
2ShlYW@~
import org.flyware.util.page.Page; ~bm2_/RL
&4$43\(D
import net.sf.hibernate.HibernateException; `^4>^
import net.sf.hibernate.Query; nm%4L
H]n0JG9K
import com.adt.dao.UserDAO; vpr@
Ga/\kO)x_
/** '_yk_[/
* @author Joa ,-NLUS
"w
*/ YH'.Yj2
public class UserDAOImpl extends BaseDAOHibernateImpl :!*;0~#
E9+O\"e9
implements UserDAO { ~.y4
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/* (non-Javadoc) x_^OS"h-
* @see com.adt.dao.UserDAO#getUserByName 0 6v5/Xf
68G] a N3
(java.lang.String) whp\*]8
*/ kjYO0!C
publicList getUserByName(String name)throws e+[J[<8
A.cZa
HibernateException { z_iyuLRdb
String querySentence = "FROM user in class /iJhCB[QZ
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com.adt.po.User WHERE user.name=:name"; m_O=X8uj"D
Query query = getSession().createQuery 'MM~~:
q,h.W JI
(querySentence); If I$
query.setParameter("name", name); 5'L}LT8p@
return query.list(); g7q]Vj
} d4=u`2w
.Y Frb+6
/* (non-Javadoc) ofhZ@3
* @see com.adt.dao.UserDAO#getUserCount() `0gK;D8t
*/ WOTu"Yj
publicint getUserCount()throws HibernateException { ` vmk
int count = 0; O%h
97^%k
String querySentence = "SELECT count(*) FROM dZ81\jdYv
=+#RyV
user in class com.adt.po.User"; xg%]\#
Query query = getSession().createQuery <:}AC{I
IHX#BY>
(querySentence); f#-T%jqnK
count = ((Integer)query.iterate().next we).8%)'
]R.Vq\A%S
()).intValue(); K{|dt W&
return count; `Q_ R/9~
} HC, 0"W
o2UJ*4
/* (non-Javadoc) z\ $>k_
* @see com.adt.dao.UserDAO#getUserByPage >Zp]vK~s
xM"XNT6b
(org.flyware.util.page.Page) -bX.4+U
*/ -(,6w?
publicList getUserByPage(Page page)throws {mr)n3
JM4`k8mM
HibernateException { Kpbber
String querySentence = "FROM user in class @<{#v.T
wI]>0geb*
com.adt.po.User"; hp%Pg &
Query query = getSession().createQuery &7nfTc
/
{bK*A!
(querySentence); Z8_gI[Zn
query.setFirstResult(page.getBeginIndex()) ee?Mo`
.setMaxResults(page.getEveryPage()); P VW9iT+c
return query.list(); hl~F1"q)
} `-`iS?
o8pe07n(W
} g\h7`-#t
"TNUw&ih
. T>}O0L"
u\;dUnr
q2pao?aa
至此,一个完整的分页程序完成。前台的只需要调用 y:Ab5/bHy
C3h!?5
userManager.listUser(page)即可得到一个Page对象和结果集对象 5}aC'j\
H<Taf%JT
的综合体,而传入的参数page对象则可以由前台传入,如果用 Nm.>C4
<"P
'"SC
webwork,甚至可以直接在配置文件中指定。 S;<?nz3
3@bjIX`=H
下面给出一个webwork调用示例: ]xeyXw84k
java代码: Lj AIB(*
&_^<B7aC'k
W {/z-&
/*Created on 2005-6-17*/ $
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package com.adt.action.user; { qx,X.5$
eBKIdR%k
import java.util.List; vrDRSc6_
< tq9
import org.apache.commons.logging.Log; -k{R<L
import org.apache.commons.logging.LogFactory; W5uI(rS<6
import org.flyware.util.page.Page; DfFPGFv
]>i0;RME
import com.adt.bo.Result; />7/S^
import com.adt.service.UserService; =KD*+.'\/
import com.opensymphony.xwork.Action; vw6FvE`lC
muq|^Hfb
/** @S:/6__
* @author Joa nx]b\A
*/ *<j @+Ch
publicclass ListUser implementsAction{ ?LFSR
i(kK!7W35
privatestaticfinal Log logger = LogFactory.getLog &fj?hYAj
mR@Xt#
(ListUser.class); n?tAa|_
Y% 9F
private UserService userService; D/`E!6Fk=
Kn\(Xd.>
private Page page; pa73`Ca]
x)5v8kgf
privateList users; H)+kN'J
m%\[1|N
/* JOq<lb=
* (non-Javadoc) Q^Z}Y~.
* [SvwJIJJ
* @see com.opensymphony.xwork.Action#execute() ]}l!L;
*/ _q$fw&
publicString execute()throwsException{ `roSOX1f
Result result = userService.listUser(page); Oei2,3l,?
page = result.getPage(); (%!R
users = result.getContent(); FI5C&d5d
return SUCCESS; ?R} oXSVT
} s~w+bwr
cyE2=
/** C^tC} n1D(
* @return Returns the page. _4]dPk#^
*/ h;M2ylOu.
public Page getPage(){ \LXC269
return page; 4e t#Q
} ^)pY2t<^
B6oAW ,3
/** =h;!# ZC
* @return Returns the users. Q(3x"+
*/ zl?N1>KS
publicList getUsers(){ E9hWn0 e
return users; dY.uOafr
} KJfyh=AD(
Dw3!
ibg
/** Oc`fQqYy
* @param page B E)l77=/
* The page to set. ^*Fkt(ida
*/ M3kE91
publicvoid setPage(Page page){ `s $@6r$
this.page = page; 6u}NI!he
} 7:%K-LeaQu
}VRo: sJb
/** 5i?U-
* @param users 3MVZ*'1QM\
* The users to set. I,;)pWX=@
*/ )O
Cr6UR
publicvoid setUsers(List users){ t79MBgZ
this.users = users; Oa
.%n9ec
} O=/Tx2i;
)Cl&"bX
/** Vba}RF[b
* @param userService rl=_ "sd=
* The userService to set. ](D [T
*/ HfiM]^
publicvoid setUserService(UserService userService){ STI3|}G*P
this.userService = userService; ) b8*>k
} )^+$5OR\c
} 3!L)7Z/
'c D"ZVm1
'=@x2`U/
NU[{oI<a
BoqW;SG$9
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, IuF-bxA
@Q!j7I
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 D>Z_N?iR
0a'y\f:6*
么只需要: BKEB,K=K@
java代码: 5EUkp6Y
0*/~9n-Vl
;}qCIyuO]
<?xml version="1.0"?> +h/$_5
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork O.dNhd$
/'(P{O>{j
1.0//EN" "http://www.opensymphony.com/xwork/xwork- E=d[pI,e
(I5ra_FVs
1.0.dtd"> =l+p nG
Yt^+31/%
<xwork> RFdN13sJv
M~IiJ9{
<package name="user" extends="webwork- .y!Hw{cq
uJ$,e5q
interceptors"> z4goa2@Z
G`z48
<!-- The default interceptor stack name 4
#N#[;M
/a_|oCeC}
--> eC-TZH@
<default-interceptor-ref ?*;zS%93U9
49m/UeNZ
name="myDefaultWebStack"/> GFidriC
ov~m?Y]h
<action name="listUser" ~0NZx8qG
')+EW"
e
class="com.adt.action.user.ListUser"> #C`!yU6(
<param [% jg;m
ZU|nKt<GK
name="page.everyPage">10</param> i=4bY[y
<result QQ9Q[c
QI-3mqL
name="success">/user/user_list.jsp</result> S;g~xo
</action> ?cvv!2B]T
{IVqV6:
</package> b/EvcN8 }
WJ*DWyd''
</xwork> `uj`ixcR
=bzTfki
^=ikxZyO
d<Di;5
<5q }j-Q
PD?H5W3@
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 lV?SvXe
[F%\1xh
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。 %YXC-E3@O
w~9gZ&hdp
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 saV `-#
;,1i,?
?>_.~b~
580t@?
=h)H`
我写的一个用于分页的类,用了泛型了,hoho Fmu R(f=
q)[gVL
java代码: 9&tV#=s
d2Y5'A0X
a
AuQw
package com.intokr.util; !ZVMx*1Cf
NXx}KF c
import java.util.List; /_O-m8+4m
TaC)N
/** 5?O"N
* 用于分页的类<br> =pNkS1ey
* 可以用于传递查询的结果也可以用于传送查询的参数<br> r\]WDX!`
* `y\:3bQ4
* @version 0.01 4u&doSXR
* @author cheng 4aRYz\yT=
*/ "`S61m_
public class Paginator<E> { bk<3oI
privateint count = 0; // 总记录数 bQ)r8[o!
privateint p = 1; // 页编号 LP~$7a
privateint num = 20; // 每页的记录数 Dt ?Fs
privateList<E> results = null; // 结果 4c% :?H@2
C {))T5G
/** =mZw71,
* 结果总数 DXUI/C f
*/ c2C8}XJ|O
publicint getCount(){ g#AA.@/Z
return count; rT#QA=YB
} |] YT6-?.
(xTHin$
publicvoid setCount(int count){ R
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this.count = count; 5s>9v
} A1C@'9R*
LF0~H}S;6B
/** q\,H9/.0k
* 本结果所在的页码,从1开始 T:ck/:ZH
* 5HU>o|.
* @return Returns the pageNo. "*0
szz'
*/ $=bN=hE
publicint getP(){ pUmB
h
return p; 5Z:HCp-aG
} ZoUfQ!2*
l|K8+5L
/** @sDd:>t
* if(p<=0) p=1 jK{MU) D+
* !xvPG
* @param p CtfSfSAUuu
*/ zQ[mO
publicvoid setP(int p){ GA|q[<U
if(p <= 0) SbZk{lWcq
p = 1; SXT/9FteZ
this.p = p; SlZu-4J.-
} =$'Zmb
[D
/b*@dy
/** kC+A7k6
* 每页记录数量 X;1q1X)K
*/ ?Cws25G
publicint getNum(){ $5A XE;~{
return num; vfj Ipg%i
} HCu1vjU(]
UYPBKf]A9
/** uODsXi{z
* if(num<1) num=1 \DHCf4,
*/ =nsY[ s<
publicvoid setNum(int num){ *~vRbD$q
if(num < 1) d+^;kse
num = 1; YZk& 'w
this.num = num; n0m9|T&
} cO8;2u,Gvi
_CZ* z
/** [bcqaT
* 获得总页数 ;?&;I!
*/ 'W#<8eJo
publicint getPageNum(){ rYLNV!_
return(count - 1) / num + 1; Z(.Tl M2h
} d/^^8XUK
VTHDGBU
/** -or9!:8
* 获得本页的开始编号,为 (p-1)*num+1 R%Z} J R.
*/ Fg~,1[8w<
publicint getStart(){ [9L(4F20
return(p - 1) * num + 1; ?>&8,p17
} @|^Ch+%@
;A C] *
/** Ue%0.G|<W
* @return Returns the results. lA1R$
*/ 7HF\)cz2
publicList<E> getResults(){ r1\.Jz
return results; wD<G+Y}
} MT*b+&1e
N\0Sq-.
public void setResults(List<E> results){ k X-AC5]
this.results = results; k >MgrtJI
} H!A^ MI
Oe#k|
public String toString(){ %9Ue`8
StringBuilder buff = new StringBuilder LU]~d<i99
hImCy9i}
(); v`fUAm/
buff.append("{"); QXrK-&fju
buff.append("count:").append(count); C]`Y PM5
buff.append(",p:").append(p); qN) cB?+
buff.append(",nump:").append(num); J]N}8 0
buff.append(",results:").append qdm!]w.G5
L`!sV-.
(results); -(2-zznZ
buff.append("}"); AE$)RhY`
return buff.toString(); zqeU>V~<F
} 51&T`i
f8j^a?d|
} Glwpu-@X
UWnH2
&A9+%kOk>