Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 WOQP$D9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }2(,K[?
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 My<snmr2d
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 dQ_!)f&w1
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分页支持类: k%D+Y(WGz8
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java代码: |p><'Q%*
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package com.javaeye.common.util; dE:+k/
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import java.util.List; ^SxY IFL
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publicclass PaginationSupport { hvA^n@nr
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publicfinalstaticint PAGESIZE = 30; BlXB7q,
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privateint pageSize = PAGESIZE; kD*2~Z ?;
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privateList items; _acE:H
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privateint totalCount; Bm"KOr$}-
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privateint[] indexes = newint[0]; Rniq(FAx
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privateint startIndex = 0; {jYOsl
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public PaginationSupport(List items, int 4T!+D
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totalCount){ c8L~S/t
setPageSize(PAGESIZE); uM_#
setTotalCount(totalCount); iTag+G4*
setItems(items); "kMguK}c
setStartIndex(0); wm)#[x #
} bKrhIU[
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public PaginationSupport(List items, int 3
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totalCount, int startIndex){ eU<]o<
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setPageSize(PAGESIZE); O+?<h{"
setTotalCount(totalCount); b!sRk@LGZ
setItems(items); :lB=Lr)
setStartIndex(startIndex); 6
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} 'h^0HE\~p
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public PaginationSupport(List items, int }z\_;\7
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totalCount, int pageSize, int startIndex){ qW!]co
setPageSize(pageSize); ~v]!+`_J
setTotalCount(totalCount); mf}O-Igte
setItems(items); q~3,yyu
setStartIndex(startIndex); dl~%MWAVb
} ?gJy3@D
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publicList getItems(){ u86"Y^d#
return items; xKQ+{"?-^g
} {_S}H1,
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publicvoid setItems(List items){ Aj2OkD
this.items = items; ~ECD`N<YF
} :{IO=^D=$
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publicint getPageSize(){ ~$p2#AqX
return pageSize; ]`&Yqg
} B
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publicvoid setPageSize(int pageSize){ _T2=J+"-Kp
this.pageSize = pageSize; )('%R|$ /
} /c2w/+ _
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publicint getTotalCount(){ L
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return totalCount; D3)zk@N
} );Z1a&K5k
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publicvoid setTotalCount(int totalCount){ Gi "941zVl
if(totalCount > 0){ 2Z3('?\z~
this.totalCount = totalCount; Y]L9Y9
int count = totalCount / iVG-_RsKK
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pageSize; P#fM:z@[
if(totalCount % pageSize > 0) qUxRM_7U
count++; =:/BV=tv
indexes = newint[count]; U7I qST
for(int i = 0; i < count; i++){ x\J#]d.
indexes = pageSize * /\H>y
LE*h9((
i; E;1Jh(58)b
} I_xXDr
}else{ tkXEHsRT
this.totalCount = 0; ;$a@J&
} mZx&Xez_G
} q*2N{
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publicint[] getIndexes(){ lWqrU1Sjl
return indexes; %-<'QYYP
} #/I[Jqf
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publicvoid setIndexes(int[] indexes){ 2 Sh
this.indexes = indexes; NMww>80
} vP!{",>
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publicint getStartIndex(){ $dA-2e10
return startIndex; 3"G>>nC&
} 8HR mQ
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publicvoid setStartIndex(int startIndex){ ~t^eiyv
if(totalCount <= 0) Oi:<~E[kz.
this.startIndex = 0; ?c7*_<W5
elseif(startIndex >= totalCount) A?`jnRo=\
this.startIndex = indexes Zc!@0
e'=MQ,EWd
[indexes.length - 1]; +3&zN(
elseif(startIndex < 0) qA!]E^0*Ke
this.startIndex = 0; ei6AV1| p
else{ MW PvR|Q
this.startIndex = indexes T}4/0yR2
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[startIndex / pageSize]; kdn'6>\
} S6fL>'uQ
} ak:ibV
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publicint getNextIndex(){ Qu7T[<
int nextIndex = getStartIndex() + y|Ir._bt
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pageSize; #'q<v"w
if(nextIndex >= totalCount) &[At`Nw71
return getStartIndex(); 3 q`)*
else 0
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return nextIndex; 2e|N@j
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} ^qC;Nh4F
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publicint getPreviousIndex(){ 3;8!rNN
int previousIndex = getStartIndex() - ZvUCI8
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pageSize; &`fhEN
if(previousIndex < 0) {&"L~>/o
return0; (I@rLvZr{
else eQVZO>)P1+
return previousIndex; J@OB`2?Zv
} o ,xxh
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} a&k_=/X&
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抽象业务类 z
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java代码: J!5v~<v?-
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/** rvyrxw%[
* Created on 2005-7-12 NNF>Xa`9,
*/ M{$j
package com.javaeye.common.business; )LdyC`S\c
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import java.io.Serializable; Z(ZiFPx2Z
import java.util.List; HXoX
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import org.hibernate.Criteria; /RyR>G!
import org.hibernate.HibernateException; @?[1_g_'P
import org.hibernate.Session; !=y]Sv~h
import org.hibernate.criterion.DetachedCriteria; rLU/W<F8
import org.hibernate.criterion.Projections; r)T:7zy
import W;1|+6x
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org.springframework.orm.hibernate3.HibernateCallback; Qjnd6uv{I
import [j"9rO" +
*#TYqCc+g
org.springframework.orm.hibernate3.support.HibernateDaoS jM&r{^(
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upport; TI !a )X
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import com.javaeye.common.util.PaginationSupport; ~h"/Tce
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public abstract class AbstractManager extends .7
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HibernateDaoSupport { /1 RAAa
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privateboolean cacheQueries = false; x)UwV
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privateString queryCacheRegion; St<mDTi
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publicvoid setCacheQueries(boolean g!i45-n3gt
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cacheQueries){ 5~.ZlGd
this.cacheQueries = cacheQueries; unJ R=~E
} 0A:n0[V:]
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publicvoid setQueryCacheRegion(String q\rC5gk>
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queryCacheRegion){ $o +5/c?|
this.queryCacheRegion = 2Sq_Tw3^
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queryCacheRegion; cD4
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} TM8=U-A
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publicvoid save(finalObject entity){ &vovA} F
getHibernateTemplate().save(entity); [DHoGy,P
} SSBg?H 'T
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publicvoid persist(finalObject entity){ ~O 3D[PNW~
getHibernateTemplate().save(entity); UA~RK2k?
} {"vkji>
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publicvoid update(finalObject entity){ >|Q:g,I
getHibernateTemplate().update(entity); 1shBY@mlq
} WU4U Zpz
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publicvoid delete(finalObject entity){ zKFp5H1!%+
getHibernateTemplate().delete(entity); eh*6cQ.0
} Eh|.
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publicObject load(finalClass entity, `imWc"'Ej
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finalSerializable id){ .P$IJUYO
return getHibernateTemplate().load I5AO?BzJ
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(entity, id); y[@\j9Hq
} 93IFcmO.H@
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publicObject get(finalClass entity, idRD![!UI
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finalSerializable id){ <e%F^#y_
return getHibernateTemplate().get J!ntXF
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(entity, id); zciCcrJ
} .bD_R7Bi6
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publicList findAll(finalClass entity){ +fKtG]$
return getHibernateTemplate().find("from '<iK*[NW
to"'By{9
" + entity.getName()); L?Yoh<
} fWGOP~0
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publicList findByNamedQuery(finalString T88Y
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namedQuery){ I1 U7.CT
return getHibernateTemplate @OV-KT[>
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().findByNamedQuery(namedQuery); z5Qs@dG
} .7ayQp
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publicList findByNamedQuery(finalString query, Hqz?E@bc@
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finalObject parameter){ rC[6lIP
return getHibernateTemplate B6}FIg)
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().findByNamedQuery(query, parameter); $!A:5jech
} f]8I64
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publicList findByNamedQuery(finalString query, rAdacnZV
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finalObject[] parameters){ _ia! mT<
return getHibernateTemplate n
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().findByNamedQuery(query, parameters); f!t69nd%L
} ']ood!
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publicList find(finalString query){ t>UkE9=3\
return getHibernateTemplate().find tGcya0RL
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(query); Zs zs1{t
} (y4#.vZh:
e yw'7
publicList find(finalString query, finalObject VY 1vXM3y
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parameter){ K_-d(
return getHibernateTemplate().find *HM?YhR
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(query, parameter); J#3{S]*v_
} L$v^afP?
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public PaginationSupport findPageByCriteria $<)Yyi>6E
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(final DetachedCriteria detachedCriteria){ _q>SE1j+W=
return findPageByCriteria Y^ve:Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); K=u0nrG*
} m)?5}ZwAH
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public PaginationSupport findPageByCriteria ES:!Vx9t0|
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(final DetachedCriteria detachedCriteria, finalint GtI6[ :1t
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startIndex){ T*q"N?/4
return findPageByCriteria !#D=w$@r:
v$|mo;6
(detachedCriteria, PaginationSupport.PAGESIZE, eTE2J~\
P]<= ! F
startIndex); 2C+(":=}
} OjnJV
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public PaginationSupport findPageByCriteria t)1phg4H)
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(final DetachedCriteria detachedCriteria, finalint p_terD:
f_r0})
pageSize, \x\.
finalint startIndex){ uVU`tDzd:
return(PaginationSupport) K!8zwb=fq
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getHibernateTemplate().execute(new HibernateCallback(){ m24v@?*
publicObject doInHibernate (RF>s.B<
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(Session session)throws HibernateException { '?/&n8J\
Criteria criteria = ,=w!vO5s
m^Lj+=Z"
detachedCriteria.getExecutableCriteria(session); M?6;|-HH
int totalCount = x(r+P9f\<
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((Integer) criteria.setProjection(Projections.rowCount whkJ pK(
L=1~ f-
()).uniqueResult()).intValue(); $-pbw@7
criteria.setProjection mc@M ,2@D
{K.rl%_|N
(null); iK}v`xq
List items = H*U`
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criteria.setFirstResult(startIndex).setMaxResults B%b_/F]e
fNhT;Bux
(pageSize).list(); /mbCP>bcG
PaginationSupport ps = N=ifIVc
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new PaginationSupport(items, totalCount, pageSize, Jh2Wr!5
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startIndex); ?eWJa
return ps; ^e9aD9
} yz)ESQ~va
}, true); Ee?;i<u
} (:} <xxl
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public List findAllByCriteria(final 5RhF+p4
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DetachedCriteria detachedCriteria){ 4]BJ0+|mT
return(List) getHibernateTemplate F3 f@9@b
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().execute(new HibernateCallback(){ T Oy7?;|=
publicObject doInHibernate 8W{~wg`
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(Session session)throws HibernateException { ~/c5hyTx
Criteria criteria = /?3:X*
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detachedCriteria.getExecutableCriteria(session); mU]s7` %<>
return criteria.list(); r{ "uv=,`
} z> :U{!5k
}, true); 'O "kt T
} v>I<|
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public int getCountByCriteria(final 9v?V
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DetachedCriteria detachedCriteria){ 2v^lD('
Integer count = (Integer) !GN Xt4D
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getHibernateTemplate().execute(new HibernateCallback(){ v72,h
publicObject doInHibernate ?'+8[OHiF^
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(Session session)throws HibernateException { C={mi#G[/
Criteria criteria = SKxe3
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detachedCriteria.getExecutableCriteria(session); N9*UMVU
return zlMlMyG4
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criteria.setProjection(Projections.rowCount W?PWJkIw
hT=f;6$
()).uniqueResult(); BGpk&.J
} uHrb:X!q
}, true); @U7Dunu*f
return count.intValue(); 51/sTx<Z}
} Vj7Hgc-,
} nt`<y0ta
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用户在web层构造查询条件detachedCriteria,和可选的 l'2H4W_+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 }z{wQ\
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PaginationSupport的实例ps。 ^6&_|f
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ps.getItems()得到已分页好的结果集 <[5#c*A
ps.getIndexes()得到分页索引的数组 u2,H ]-
ps.getTotalCount()得到总结果数 G|V\^.f<
ps.getStartIndex()当前分页索引 (olLB
ps.getNextIndex()下一页索引 TPqvp|~2
ps.getPreviousIndex()上一页索引 aZxO/b^j
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 cS
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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 _M&{^d
h;}ODK(.
一下代码重构了。 }(cY|
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我把原本我的做法也提供出来供大家讨论吧: U[Nosh)hu\
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首先,为了实现分页查询,我封装了一个Page类: mQnL<0_<f
java代码: tKX}Ok:V%
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/*Created on 2005-4-14*/ VX&WlG`wa
package org.flyware.util.page; U~hCn+0
pNSst_!>
/** ;6zPiaDQ
* @author Joa W\a!Q]pV
* PgTDjEo
*/ fYs?D+U;PF
publicclass Page { p&m
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/** imply if the page has previous page */ `+Xe'ey
privateboolean hasPrePage; c-|kv[\a
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/** imply if the page has next page */ *H?t;,\
privateboolean hasNextPage; `TkbF9N+
h\2}875
/** the number of every page */ p^Agh
privateint everyPage; -2z,cj&E{
"C& J wm?
/** the total page number */ 9G+y.^/6
privateint totalPage; z=[l.Af_
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/** the number of current page */ <(Tiazg
privateint currentPage; +!G4tA$g
p ^](3Vi(
/** the begin index of the records by the current R^|!^[WE
9Dy)nm^
query */ srhFEmgN7)
privateint beginIndex; !4_!J (q%
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/jvOXS\M
/** The default constructor */ c'xUJhEL
public Page(){ QW,cn7
T 4vogoy
} VmMh+)UZ
htQ;m)>J:
/** construct the page by everyPage =P)"NP7f'
* @param everyPage ]|t9B/()i
* */ @{'o#EJY
public Page(int everyPage){ x}_rnf_
this.everyPage = everyPage; .:T9pplq
} \?r$&K]4
a4:`2
/** The whole constructor */ &bn*p.=G
public Page(boolean hasPrePage, boolean hasNextPage, QaIi.*tic
eS*
*L3
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int everyPage, int totalPage, FF8WTuzB+
int currentPage, int beginIndex){ hJ<:-u+yk}
this.hasPrePage = hasPrePage; R !jhwY$
this.hasNextPage = hasNextPage; _ \_3s
this.everyPage = everyPage; f>|9 l
this.totalPage = totalPage; 8u/3?Kc
this.currentPage = currentPage; LPb]mC6#
this.beginIndex = beginIndex; #&}%70R)
} >s44
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/** \f6lT3"VN
* @return i'U,S`L6>
* Returns the beginIndex. H&w(]PDh
*/ zI1(F67d`
publicint getBeginIndex(){ G,+xT}@wu
return beginIndex; O.]_Ry\OXA
} 3&O% &
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/** m2jwqx{G
* @param beginIndex "$# $f
* The beginIndex to set. :O5Tr03z
*/ G[ ,,L
publicvoid setBeginIndex(int beginIndex){ ?Ozk^#H[
this.beginIndex = beginIndex; aeLBaS
} 1hF2eNh
2Y9y5[K,F)
/** |}l@w+N3
* @return n+v!H O"2u
* Returns the currentPage. X *_
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*/ :8GlyN<E
publicint getCurrentPage(){ E=$7ieW
return currentPage; 8[vl3C
} u!hqq^1
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/** 6(\q< fx
* @param currentPage q]2}UuM|U
* The currentPage to set. Sr4dY`V*:z
*/ UDhwnGTq(l
publicvoid setCurrentPage(int currentPage){ _HSTiJVr
this.currentPage = currentPage; 8 h55$j
} y.L|rRe@P
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/** jI@bTS o
* @return U/}AiCdj@
* Returns the everyPage. Pc/.*kOT
*/ U@1#!ZZ6
publicint getEveryPage(){ .%-6&%1
return everyPage; gvow\9{|C
} ;}UIj{sj*
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/** I8E\'`:<
* @param everyPage f'7d4
* The everyPage to set. 1^n5CI|7u
*/ iKP\/LR<n
publicvoid setEveryPage(int everyPage){ pZni,<Q
this.everyPage = everyPage; SQz$kIZR
} g?k#wj1uH
yt]Oj*nn0K
/** }TXp<E"\
* @return &!3VqHQ`
* Returns the hasNextPage. `kaR@t
*/ a!s.850@
publicboolean getHasNextPage(){ ymzPJ??!
return hasNextPage; <z~2d
} HYa$EE2
hlABu)B'1
/** _47j9m]f
* @param hasNextPage r"HbrQn
* The hasNextPage to set. X^?|Sz<^E
*/ 7]<F>97
publicvoid setHasNextPage(boolean hasNextPage){ vV$hGS(f~
this.hasNextPage = hasNextPage; p*(U*8Q
} nN(D7wk
6!gtve_
/** -Z[R S{#+T
* @return s[vPH8qb
* Returns the hasPrePage. vTe$77n
*/ >*<6 zQf
publicboolean getHasPrePage(){ +73=2.C0
return hasPrePage; =:ya;k&
} `\WcF7
ai<MsQQ:=
/** FVvv
* @param hasPrePage 'p|Iwtjn>
* The hasPrePage to set. oF 1W}DtA
*/ mE3SiR "
publicvoid setHasPrePage(boolean hasPrePage){ O>tC]sm%
this.hasPrePage = hasPrePage; gKm@B{rC
} U_N5~#9
7Y_fF1-wY
/** m=("N
* @return Returns the totalPage. Sm*Jysy`
* x):k#cu[L
*/ o[Wagg.%
publicint getTotalPage(){ G{&yzHAuae
return totalPage; Mo?t[]L
} D-2v>l_
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/** priT7!
* @param totalPage <?=mLOo=
* The totalPage to set. E<98ahZ?l
*/ tNi%}~Z
publicvoid setTotalPage(int totalPage){ \r1kbf7?
this.totalPage = totalPage; GtAJ#[5w
} D~i@. k
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} 8-y: == C
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qD=m{O8%_
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3_jCsX
U`8^N.Snrp
个PageUtil,负责对Page对象进行构造: G2[IO $
java代码: SCt=OdP=
9wYtOQ{g
JtrDZ;^@
/*Created on 2005-4-14*/ c|!A?>O? i
package org.flyware.util.page; %M0mwty]
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import org.apache.commons.logging.Log; 4,*^QK
import org.apache.commons.logging.LogFactory; bN7 UO
aJa^~*N/Aa
/** =p&'_a^$
* @author Joa H-\{w
* >`rNT|rg
*/ 5E oWyy
publicclass PageUtil { HHu7{,
l:5CM[mZ
privatestaticfinal Log logger = LogFactory.getLog 9Sj:nn^/u
Uf2v$Jl+Yh
(PageUtil.class); Kn!0S<ssR
z
kX-"}$8
/** dbq{a
* Use the origin page to create a new page k,*#I<($
* @param page #@\NdW\
* @param totalRecords afP&+ 5t@O
* @return wMPw/a;
*/ "<jEI /
publicstatic Page createPage(Page page, int mZ0oa-Iy
fO|~Oz<S
totalRecords){ 0@FM^ejA#
return createPage(page.getEveryPage(), e
ka@?`
{i%xs#0h
page.getCurrentPage(), totalRecords); rM
>V=|9,
} F#}1{$)%
/
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/** K9qEi{[
* the basic page utils not including exception Ignv|TYG
U3j~}H.D1
handler gHh.|PysW
* @param everyPage
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* @param currentPage 5q_OuZ/6
* @param totalRecords Uh|__DUkh
* @return page r)#"$Sm
*/ w[$nO#
publicstatic Page createPage(int everyPage, int
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currentPage, int totalRecords){ yL3<X w|
everyPage = getEveryPage(everyPage); 7U[L\1zS
currentPage = getCurrentPage(currentPage); | 8L`osg
int beginIndex = getBeginIndex(everyPage, %d[xr h
rX>y>{w~
currentPage); ZV q
int totalPage = getTotalPage(everyPage, [ls ?IFg
xm10
totalRecords); /E4 }d=5L
boolean hasNextPage = hasNextPage(currentPage, ,8"[ /@
C}P
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totalPage); ?'/5%f`
boolean hasPrePage = hasPrePage(currentPage); ox=7N{+`J
r?yJ
returnnew Page(hasPrePage, hasNextPage, ;Y|~!%2~
everyPage, totalPage, 5fx,rtY2sQ
currentPage, > v!c\
BQ}.+T\
beginIndex); >wS:3$Q
} E#2k|TpH4
`w=H'"Zv
privatestaticint getEveryPage(int everyPage){ -z 5k4Y
return everyPage == 0 ? 10 : everyPage; .kKwdqO+zB
} ~!d)J
,S0~:c:)
privatestaticint getCurrentPage(int currentPage){ Mm7n?kb6
return currentPage == 0 ? 1 : currentPage; %1?V6&
} vB YT)S
CygV_q
privatestaticint getBeginIndex(int everyPage, int v4>"p!_C
x^O2Lj,w\
currentPage){ +l?ro[#6&.
return(currentPage - 1) * everyPage; 73z|'0.
} vwH7/+
.q9|XDqQc
privatestaticint getTotalPage(int everyPage, int $E,DxDT
ic]tUOC :
totalRecords){ :0j`yo:w
int totalPage = 0; ]|LaMMD
hCvLwZ?LF
if(totalRecords % everyPage == 0) Ufe
totalPage = totalRecords / everyPage; :9
iOuu
else Nx (pJp{S
totalPage = totalRecords / everyPage + 1 ; $0S" Lh{
j _9<=Vu
return totalPage; >.wd)
} #M^Yh?~%w
IZv, Wo
privatestaticboolean hasPrePage(int currentPage){ s>``-
]3
return currentPage == 1 ? false : true; = 4WZr
} Nl<,rD+KSD
^}7t:
privatestaticboolean hasNextPage(int currentPage, 7RFkHME
IS
9q 5/]
int totalPage){ p>tdJjnt
return currentPage == totalPage || totalPage == ;q&D,4r]
$F()`L{Tj
0 ? false : true; @gjdyz
} @bCiaBdi
0#/
6P&6
$z,DcO.vz
} VrE5^\k<a
1LIV/l^}f
Hh;6B!zb+
v_h*:c
:;WDPRx
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Eg29|)qsz
:aqskeT
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 wVJFA1
yIf}b
做法如下: LqsJHG
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^r
:A^q
Y <k,E
的信息,和一个结果集List: jh&vq=PH
java代码: C$ `Y[w
3 DHA^9<q
N_Ld,J%g
/*Created on 2005-6-13*/ [=F
|^KL
package com.adt.bo; htrj3$q(4
6SO7iFS
import java.util.List; 6%INNIyAWa
}Q^a.`h
import org.flyware.util.page.Page; *>$)#?t
&p4<@k\L
/** AX RNV
* @author Joa }/r%~cZ
*/ _:p_#3s$
publicclass Result { }Y ];ccT
tRBK1h
private Page page; =?Md&%j
I8]NY !'cW
private List content; PM>XT
AHD%6 \$
/** W*`6ero
* The default constructor pDq_nx9
*/ TPFmSDq
public Result(){ f:&OOD o
super(); "]V|bz o0a
} * .VZ(wX
1+}Ud.v3VW
/** V>92/w.fe
* The constructor using fields <1.mm_pw
* -%)
!XB
* @param page ;O|63
* @param content dKTAc":-}
*/ `2+e\%f/0
public Result(Page page, List content){ |6^ K
this.page = page; Z?'|9FM
this.content = content; ea>\.D-S
} 1W<_5 j_
T@Z{KV"S
/**
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* @return Returns the content. -Ep6.v
*/ aW$nNUVD
publicList getContent(){ Z x%@wH~
return content; fr2w k}/b
} RcP5].^T
iZ\z!tH R
/** -JK4-Hg
* @return Returns the page. d( g_y m*
*/ 7e[\0:Z
public Page getPage(){ r!,V_a4n
return page; f.^w/ GJO/
} ScoHtX3
oz@6%3+
/** 7!nAWlQ&-E
* @param content Hvo27THLo
* The content to set. Y{tuaBzD
*/ /y|r iW
public void setContent(List content){ ~GYtU9s5
this.content = content; $Xc<K_Z
} eJp-s" %
9'h^59
/** !OgoV22
* @param page [`\Qte%UH
* The page to set. 'FFc"lqj
*/ :K:gyVrC
publicvoid setPage(Page page){ .Kwl8xRg
this.page = page; (C@@e'e
} htym4\Z=
} 7'uc;5:
!I_4GE,
@{lnfOESl
_/ZY&5N
5VbNWrw
2. 编写业务逻辑接口,并实现它(UserManager, 6E]rxps}"
zAUfd[g
UserManagerImpl) TeqsP1{?
java代码: j~q`xv+R
Mwc3@
rtE,SN
/*Created on 2005-7-15*/ IyP].g1"U
package com.adt.service; X&Lt?e,&
.y+U7"?s*
import net.sf.hibernate.HibernateException; ),,vu
5-^twXC&
import org.flyware.util.page.Page; $8r:&Iw
oD\+ 5[x
import com.adt.bo.Result; -m/4\D
qDAjW)w
Jp
/** T<)z2Bi
* @author Joa M7 !"
t
*/ q|J]
publicinterface UserManager { "QS7?=>*F
||aU>Wj4
public Result listUser(Page page)throws >,3
3Jx
xK3;/!\`
HibernateException; Kx0dOkE
d*L'`BBsp
} 1[^d8!U
dZmq
y>8?RX8
q3`t0eLZ
o:<3n,T
java代码: ^dv>n]?
7<D_ h/WV
y{JkY\g
/*Created on 2005-7-15*/ F}>`3//u
package com.adt.service.impl; BYU.ptiJJ
q=6Y2Q
import java.util.List; 7i.aZ2a%
sSUd;BYf
import net.sf.hibernate.HibernateException; aDuanGC/V
B!@0(A
import org.flyware.util.page.Page; pdSyx>rJ
import org.flyware.util.page.PageUtil; *gVv74;;
ez{&Y>n
import com.adt.bo.Result; n}{cs
import com.adt.dao.UserDAO; _8
J(;7
import com.adt.exception.ObjectNotFoundException; }q9f,mz
import com.adt.service.UserManager; cqudF=q
rY}ofq7b
/** p~IvkW>ln)
* @author Joa )A%Y
wI$
*/ G>x0}c
publicclass UserManagerImpl implements UserManager { ~55>uw<
s8Oz^5p(
private UserDAO userDAO; #SueT"F
WM26-nR
/** A_%w(7o"
* @param userDAO The userDAO to set. k1J}9HNYR
*/ /
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publicvoid setUserDAO(UserDAO userDAO){ 1zRO==b
this.userDAO = userDAO; M &J*I
} ]mSVjF3l
?L^ Gu ]y
/* (non-Javadoc) {Hu0
* @see com.adt.service.UserManager#listUser >pKI'
Sf9+TW
(org.flyware.util.page.Page) f$|v
*/ xh0!H|
R
public Result listUser(Page page)throws uypD`%pC
LKa_ofY
HibernateException, ObjectNotFoundException { P6Ei!t,>
int totalRecords = userDAO.getUserCount(); x%1Rp[
if(totalRecords == 0) M3%<kk-_
throw new ObjectNotFoundException 'mF}+v^
)1/O_N6C
("userNotExist"); ^^#A9AM
page = PageUtil.createPage(page, totalRecords); vs~*=d27Pf
List users = userDAO.getUserByPage(page); o=ex{g( 3
returnnew Result(page, users); k:sh:G+=$d
} J3=jC5=J4
R)/w
} +dfSCs
sC>8[Jatd
2 E^P=jU`
Sc&_6}K
S:gP\Atf>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 # V+e
* 7CI q
询,接下来编写UserDAO的代码: _),@^^&x
3. UserDAO 和 UserDAOImpl: A Ho<E"R\
java代码: <$E8T>U
M5]wU
# /T)9 =m
/*Created on 2005-7-15*/ OR3TRa XD
package com.adt.dao; A.n1|Q#
RW5T}
import java.util.List; a^BD55d?
T~la,>p|}
import org.flyware.util.page.Page; c}A^0,"z>
]#`bYh^y
import net.sf.hibernate.HibernateException; [{YV<kN
%llG/]q#
/** l<5!R;?$
* @author Joa AWw'pgTQX
*/ Lxl?6wZ
publicinterface UserDAO extends BaseDAO { (U)=t$=o
XIU2l}g
publicList getUserByName(String name)throws lG2){){j
}U9e#>ex
HibernateException; d<]/,BY'
)j](_kvK
publicint getUserCount()throws HibernateException; V%))%?3x_
Mvux=Ws
publicList getUserByPage(Page page)throws H_9~gi
tZJKB1#WbP
HibernateException; sB $!X@
!*p lK6a
} :H~r
_>E
!)GPI?{^5
DGcd|>q
Y #\e~>K
bbz86]AhY
java代码: OnG?@sW+4!
k,2%%m
8 _>R 'u[
/*Created on 2005-7-15*/ 5QlJX
package com.adt.dao.impl; grZN.zTO
,W.O*vCA
import java.util.List; Mf?4 `LM
-Jb
I7Le
import org.flyware.util.page.Page; >6Q-e$GS@
\o/oM,u
import net.sf.hibernate.HibernateException; PWTAy\
import net.sf.hibernate.Query; #N*~Q
nv|&|6?`oK
import com.adt.dao.UserDAO; $lvpBs
~`y6YIJ3
/** B|!Re4`0
* @author Joa d6uL;eR
*/ )pg?Z M9
public class UserDAOImpl extends BaseDAOHibernateImpl lm$T`:c
wDn5|F}i&
implements UserDAO { "F=O
_]B'C
/* (non-Javadoc) 5'X.Z:
* @see com.adt.dao.UserDAO#getUserByName rKO[;]_*
ur;8uv2o
(java.lang.String) &Oe,$%{hBh
*/ 1&U U6| X
publicList getUserByName(String name)throws AtSEKpKc
^s^X n QhE
HibernateException { nfc&.(6x<
String querySentence = "FROM user in class Jg@PhN<9
ALhu\x>AY
com.adt.po.User WHERE user.name=:name"; ;%Qu;FtC
Query query = getSession().createQuery xand%XNv
J5429Soo
(querySentence); dH8H<K~
query.setParameter("name", name); 9T)-|fja_
return query.list(); C/)Xd^#
} 5K,Y6I&$SJ
W}Z'zU?[
/* (non-Javadoc) 0Nmd*r
* @see com.adt.dao.UserDAO#getUserCount() f"z96{zo
*/ @X|Cu bJ
publicint getUserCount()throws HibernateException { E;k'bz
int count = 0; 9%|!+!j
String querySentence = "SELECT count(*) FROM .QW89e,O3
jfk`%CEk=
user in class com.adt.po.User"; fF;-d2mF
Query query = getSession().createQuery fxjs"rD5
%{axoGd
(querySentence); WUKYwA/t
count = ((Integer)query.iterate().next ri6_u;Ch
TeQpmhN
()).intValue(); geua8;
return count; QD<f)JZK
} :hZYh.y\l
/.P*%'g
/* (non-Javadoc) I
U/gYFT
* @see com.adt.dao.UserDAO#getUserByPage Po% V%~
_L9`bzZj
(org.flyware.util.page.Page) Or0=:?4`
*/
t;{/Q&C
publicList getUserByPage(Page page)throws 9|fg\C
.^ soX}
HibernateException { =}F &jl
String querySentence = "FROM user in class sT| 8a
IF<pT)
com.adt.po.User"; .#@*)1A#t
Query query = getSession().createQuery tv5G']vO\
6Z0@4_Y@B6
(querySentence); ml\A)8O]j/
query.setFirstResult(page.getBeginIndex()) +Uq$'2CT
.setMaxResults(page.getEveryPage()); :A>cf}
return query.list(); BZe x
} h49|x&03
?(H/a-(:v}
} fM6Pw6k
tRFj<yuaq
jUYb8:B
#2s$dI
K08xiMjl
至此,一个完整的分页程序完成。前台的只需要调用 5$/ED3mcK
uPhFBD7
userManager.listUser(page)即可得到一个Page对象和结果集对象 :>] =YE
4u0=/pfi[
的综合体,而传入的参数page对象则可以由前台传入,如果用 gh#9<
xx_]e4
webwork,甚至可以直接在配置文件中指定。 Y:XE4v/)@L
/0IvvD!7N
下面给出一个webwork调用示例: nD6NLV%2x
java代码: wknX\,`Q
S{&,I2aO
`{#0C-
/*Created on 2005-6-17*/ zuwlVn
package com.adt.action.user; F|Pf-.r`t
_SY4Qs`d
import java.util.List; 1:(qoA:
k?ZtRhPu3X
import org.apache.commons.logging.Log; =Q>'?w>
import org.apache.commons.logging.LogFactory; x4Q*~,n
import org.flyware.util.page.Page; 9KkxUEkW
LB1LQ0M
import com.adt.bo.Result; hOG9
import com.adt.service.UserService; [@(M%
import com.opensymphony.xwork.Action; j#hFx+S
gMS-mkZ
/** 3 -Nwg9U
* @author Joa Gm~jC <
*/ ErnjIx:
publicclass ListUser implementsAction{ ;EDc1:
~.;+uH<i
privatestaticfinal Log logger = LogFactory.getLog xM"k qRZ
pUi|&F K">
(ListUser.class); 2dg+R)%
'B>fRN
private UserService userService; AwN7/M~'
I&%{%*y
private Page page; VC$,Y
~gg(i"V
privateList users; }coSMTMv6
ra2sYH1wr
/* l+`f\ },
* (non-Javadoc) X: PB
}
* Y">m g=B
* @see com.opensymphony.xwork.Action#execute() 1j"_@?H[
*/ &3~lZa;D
publicString execute()throwsException{ CobMagPhr
Result result = userService.listUser(page); Xfo3fW)s
page = result.getPage(); Jas=D
users = result.getContent(); FOz~iS\
return SUCCESS; ;aXu
} $=3&qg"!
7/C,<$Ep
/** /Y|y0iK
* @return Returns the page. 4IfOvAN%
*/ RrB)u?
public Page getPage(){ HGIPz{/5U
return page; {S[+hUl
} -hL 0}Wy$N
/q[5-96c
/** d^b(Uo=$
* @return Returns the users. gJ;jh7e@
*/ PY.4J4nn|
publicList getUsers(){ IY_u|7d
return users; IDCuS
} }Rl^7h<!
2yB)2n#ut
/** 9)2kjBeb
* @param page "wwAbU<
* The page to set. t3LRmjL
*/ H[oCI|k
publicvoid setPage(Page page){ ^<u9I5?
this.page = page; 5@ c/,6l
} n@1;5)&k~
q-?
k=RX`
/** PH!^ww6
* @param users (S<Z@y+d
* The users to set. kD"BsL*6!
*/ Qk`ykTS!
publicvoid setUsers(List users){ iB-h3/
this.users = users; <;eXbO>Q
} ;&iZ{
.0ov>4,R
/** ={'*C7K)oK
* @param userService s0D,n1x
* The userService to set. R k'5L
*/ F6'[8f
publicvoid setUserService(UserService userService){ 7c.96FA
this.userService = userService; Jeb"t1.$
} HV0! G-h
} &>%R)?SZh
nrFuhW\r
J]h$4"
x{'3eJ^8
BeR7LV
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, Aho zrroV
NCu:E{([
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 Nj5V" c
X6h@K</c^:
么只需要: +O]jklS4H
java代码:
WRdBL5
$~^Y4 }
m
<t~RGn3
<?xml version="1.0"?> k 'CM^,F&
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork P
}BU7`8
^k#.;Q#4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }^b7x;O|
heizO",8.&
1.0.dtd"> --D&a;CO}
76'@}wNnw
<xwork> V?[dg^*0
r:.ydr@
<package name="user" extends="webwork- EdH;P\c
xY_<D+OV
interceptors"> $4Vp l
4hQ.RO
<!-- The default interceptor stack name JkfVsmc<{h
j:Y1
--> dGc<{sQzB
<default-interceptor-ref nuvRjd^N
j Z6]G{
name="myDefaultWebStack"/> MJyz0.9 c
&gv{LJd5b
<action name="listUser" %)t9b@c!}
J 7/)XS
class="com.adt.action.user.ListUser"> Q$`u=-h|
<param \gU=B|W
s3Wjg
name="page.everyPage">10</param> xPcH]Gs^b
<result J$+K't5BZ
U??T>
name="success">/user/user_list.jsp</result> =!R+0
</action> )8,) &F
Sd9%tO9mf
</package> %%-hax.x0X
XC NM
</xwork> V_.n G;
<R%]9#re
;WG6|QgV?-
6.|Qyk*
wy)I6`v
?oKY"C8/
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 h_{//W[
T+9#&
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。 b7nER]R
&Fxw19[G
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 'c")]{
iR`c/
e.<y-b?
p"lTZ7c:Y
$:
%U`46%s
我写的一个用于分页的类,用了泛型了,hoho vi:IO
Ev' BmDk
java代码: ,cg%t9
CG -^}xE:
dDeImSeV
package com.intokr.util; ejID5NqG
t(,_
import java.util.List; 4PVkKP'/
vxmz3ht,Q
/** hrt]Qn&
* 用于分页的类<br> Cc7YjsRW
* 可以用于传递查询的结果也可以用于传送查询的参数<br> JC[G5$E
* spV E'"^
* @version 0.01 fQtV-\Bc
* @author cheng -55Pvg0ND
*/ 68pB*(i
public class Paginator<E> { >gqd
y*Bg
privateint count = 0; // 总记录数 %%=PpKYtSD
privateint p = 1; // 页编号 AlQE;4yX
privateint num = 20; // 每页的记录数 $u`v
k|\R
privateList<E> results = null; // 结果 4z$}e-
9*"Ae0ok1
/** YH%aPsi
* 结果总数 T9,T'y>BD
*/ oK! W<#
publicint getCount(){ zURob MpE#
return count; 6)QJms
} 'W>Zr}:
p?q~.YY
publicvoid setCount(int count){ T{VdlgL
this.count = count; E(l'\q'.
} ELlTR/NW
GG KD8'j]
/** /J-:?./
* 本结果所在的页码,从1开始 g'F{;Ur
* ;is *[r\|1
* @return Returns the pageNo. 13X0LN
*/ < mb.F -8
publicint getP(){ _ zh>q4M
return p; <Fc @T4Q,
} rps2sXGr
^JKV~+ Q
/** f"8!uE*;
* if(p<=0) p=1 JDIQpO"Qji
* cc"L> XoK
* @param p w,'"2^Cwy
*/ Fa!6*K\
publicvoid setP(int p){ cnrS.s=
if(p <= 0) o,#[Se*n
p = 1; D m|_;iO,
this.p = p; %S2^i3
} /%fa_+,|-
%Q0J$eC
/** ?2#v`Z=L;
* 每页记录数量 K1F,M9 0]
*/ &?-LL{W{
publicint getNum(){ 7xmyjy%c
return num; :n4X>YL)
} :4ndU:.L
3e<FlH{
/** RuW62QSq
* if(num<1) num=1 h7EKb-@
*/ 2rr}5i)r|
publicvoid setNum(int num){ {APsi7HYBr
if(num < 1) m
_0D^e7#
num = 1; v0ngM)^q
this.num = num; b0~AN#Es
} _-vf<QO]
/p=9"?
/** b`4R`mo
* 获得总页数 X CjYm
*/ HhmC+3w.7
publicint getPageNum(){ &r{.b#7\/A
return(count - 1) / num + 1; *acN/Ca1
} (Oc[j{6q
R"au8f.
/** 2hjR'6h"Y
* 获得本页的开始编号,为 (p-1)*num+1 1D,$Az~.
*/ A1zqm_X5)P
publicint getStart(){ HlkG^:)
return(p - 1) * num + 1; rt7Ma2tK
} 2 us-s
&*I\~;1
/** L=. 4x=%%
* @return Returns the results. ?ah<Qf]
*/ =ZsM[wd
publicList<E> getResults(){ MZ(TST"
return results; q+MV@8w
} FyZa1%Tv@
k
\|[=
public void setResults(List<E> results){ H$:Z`CQt<
this.results = results; VtR?/+8X
} 5aF03+ko
,1\nd{
public String toString(){ vZdn
StringBuilder buff = new StringBuilder YHVJg?H3
O};U3=^0f
(); T;eA<,H
buff.append("{"); Su<Ggv"
buff.append("count:").append(count); +TzF*Np
buff.append(",p:").append(p); |P_\l,f8`
buff.append(",nump:").append(num); xZ51iD$
buff.append(",results:").append :q V}v2
1_Um6vS#
(results); TJ:B_F*bSk
buff.append("}"); OHqc,@a;+
return buff.toString(); $J/Z~(=JT
} O7#ECUH
~~?4w.k
} k)W8%=R
BReNhk)S
f6 zT