Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 gx,BF#8}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 x$ z9:'U
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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 Jm0o[4
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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 r$7fw}'I
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分页支持类: ^~\cx75D
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java代码: c4H5[LPF
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package com.javaeye.common.util; vU=+
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import java.util.List; ixc~DV+@[
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publicclass PaginationSupport { %A_h!3f&
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; j8gw]V/B:
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privateList items; }e[;~g\&
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privateint totalCount; N1dv}!/*.+
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privateint[] indexes = newint[0]; R)}ab{A
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privateint startIndex = 0; $646"1S
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public PaginationSupport(List items, int YKCd:^u
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totalCount){ ,gY bi-E
setPageSize(PAGESIZE); NHI(}Ea|]
setTotalCount(totalCount); Js{X33^Ju
setItems(items); KYe@2 6
setStartIndex(0); r5#8Vzr
} Z]VmTB
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public PaginationSupport(List items, int {k:W?`
:&59N^So|
totalCount, int startIndex){ z#DgoA
setPageSize(PAGESIZE); v>S[}du
setTotalCount(totalCount);
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setItems(items); &:Mk^DH5
setStartIndex(startIndex); [22>)1<(
} `Ckx~'1M:
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public PaginationSupport(List items, int LHJ}I5zv
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totalCount, int pageSize, int startIndex){ CSu}_$wC#
setPageSize(pageSize); Obj?, O
setTotalCount(totalCount); SLGo/I*
setItems(items); mEh([ZnY
setStartIndex(startIndex); 3y9R1/!
} 5}v<?<l9\
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publicList getItems(){ u(kacQ7
return items; jPu m2U_
} o=%pR|
c}$C=s5 h}
publicvoid setItems(List items){ l:'\3-2a
this.items = items; a%FM)/oI|T
} 0-VC$)S
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publicint getPageSize(){ ]?1n-w.}r
return pageSize; L+GVB[@3Y
} PP1?UT=]
* |dz.Tr
publicvoid setPageSize(int pageSize){ j*7#1<T
this.pageSize = pageSize; -9f+O^x
} lPBWpHX
#.KVT#%~{
publicint getTotalCount(){ %qI.Qw$
return totalCount; sfo+B$4|
} TAE@KSPvo
}I )%G w
publicvoid setTotalCount(int totalCount){ |O!G[|/3
if(totalCount > 0){ kuX{2h*`
this.totalCount = totalCount; q2SlK8`QJ
int count = totalCount / =#z8CFq[O
#?^%#"~4H
pageSize; ].(l^W
if(totalCount % pageSize > 0) GE S_|[Q
count++; 4lCEzWo[/
indexes = newint[count]; XCAy _fL<B
for(int i = 0; i < count; i++){ Mtw7aK
indexes = pageSize * k1h>8z.Tg
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i; X`s6lV%\
} ,SZYZ 25
}else{ O3*}L2j@
this.totalCount = 0; vAV{HBQ*
} 9$~a&lXO5
} AuW-XK.
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publicint[] getIndexes(){ _G62E$=
return indexes; 9|{t%F=-
} le*'GgU#
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publicvoid setIndexes(int[] indexes){ 8hZYZ /T
this.indexes = indexes; 7A=*3
} D\@)*"
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publicint getStartIndex(){ qRbU@o.3
return startIndex; 4DTT/ER'qA
} C{<dzooz
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publicvoid setStartIndex(int startIndex){ f_m~_`m
if(totalCount <= 0) Uv|?@zy#
this.startIndex = 0; SJai<>k h
elseif(startIndex >= totalCount) ~!iZn
this.startIndex = indexes Acl?w }Y
r:~q{
[indexes.length - 1]; +U^H`\EUr
elseif(startIndex < 0) V/dL-;W;
this.startIndex = 0; 7.W$6U5
else{ ahmxbv3f=5
this.startIndex = indexes t`!@E#VK
oQ{
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[startIndex / pageSize]; q L-Ni
} tmgZNg
} &`LR{7m
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publicint getNextIndex(){ K @h94Ni6
int nextIndex = getStartIndex() +
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pageSize; }Nc Ed;
if(nextIndex >= totalCount) ? `+G0VT
return getStartIndex(); 9cJ1J7y
else AcQmY?
return nextIndex; p`=v$_]?(
} 9Z^\b)x
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publicint getPreviousIndex(){ QP~Iz*J'
int previousIndex = getStartIndex() - E
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=#.qe=
pageSize; \T:*tgU
if(previousIndex < 0) <KEVA?0>
return0; 1Pp2wpD4iC
else `#c36
return previousIndex; gnWEsA\!
} r=4vN=:
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} 1> 'xmp+#
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抽象业务类 XbYST%|.
java代码: Q*W$!ZUT
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/** r-'CB
* Created on 2005-7-12 Xwz'h;Ks_
*/ /1z3Q_M
package com.javaeye.common.business; r=cm(AHF
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import java.io.Serializable; E(miQ
import java.util.List; #8CeTR23cw
d]I3zSIC
import org.hibernate.Criteria; &S9O:>=*
import org.hibernate.HibernateException; pp1kcrE\M
import org.hibernate.Session; \}EJtux q
import org.hibernate.criterion.DetachedCriteria; q!Q*T^-rO
import org.hibernate.criterion.Projections; i0g/'ZP
import I2^@>/p8\(
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org.springframework.orm.hibernate3.HibernateCallback; S '(K
import 8o\KF(I
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org.springframework.orm.hibernate3.support.HibernateDaoS X ApSKJ
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upport; v:zKn[;o
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import com.javaeye.common.util.PaginationSupport; ^"GDaMF
~@%#eg
public abstract class AbstractManager extends 7Rl/F1G o}
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HibernateDaoSupport { YtFH@M
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privateboolean cacheQueries = false; T_I ApC
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privateString queryCacheRegion; N+CcWs!E
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publicvoid setCacheQueries(boolean [ n2)6B\/
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cacheQueries){ #m6W7_
this.cacheQueries = cacheQueries; }_,={<g
} L5n /eg:Q
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publicvoid setQueryCacheRegion(String Jie=/:&
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queryCacheRegion){ 5fuYva
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this.queryCacheRegion = V1
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queryCacheRegion; j*L-sU
} a(IZ2Zmr
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publicvoid save(finalObject entity){ 2bt).gGm
getHibernateTemplate().save(entity); +O?`uV
} 4cZlQ3OE.
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publicvoid persist(finalObject entity){ w|(
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getHibernateTemplate().save(entity); .,&6 x.
} IiZXIG4H
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publicvoid update(finalObject entity){ >fx/TSql:J
getHibernateTemplate().update(entity); 9HG" }CGZP
} nV>=n,+s"
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publicvoid delete(finalObject entity){ RWdx)qj{
getHibernateTemplate().delete(entity); ^KjxQO6y3
} :~LOw}N!aQ
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publicObject load(finalClass entity, )Kg_E6
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finalSerializable id){ 2|D<0d#W
return getHibernateTemplate().load KD73Aw
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(entity, id); Q|tzA10E
} (Z#j^}G_l
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publicObject get(finalClass entity, 0khAi|PY
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finalSerializable id){
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return getHibernateTemplate().get gjc[\"0a5h
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(entity, id); R0bWI`$Z
} -MuKeCgi
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publicList findAll(finalClass entity){ .(X!*J]G
return getHibernateTemplate().find("from 2PQY+[jx
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" + entity.getName()); (k24j*1e$
} &n9srs
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publicList findByNamedQuery(finalString
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namedQuery){ MURHv3
return getHibernateTemplate g{^(EZ,
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().findByNamedQuery(namedQuery); cBDOA<]r,
} @h)X3X
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publicList findByNamedQuery(finalString query, DPylc9[-
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finalObject parameter){ m}GEx)Y D
return getHibernateTemplate {!37w[s~
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().findByNamedQuery(query, parameter); -A)/CFIZ
} qY|NA)E)Bp
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publicList findByNamedQuery(finalString query, Vo(V<2lw}
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finalObject[] parameters){ 28=L9q
return getHibernateTemplate >|_B=<!99W
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().findByNamedQuery(query, parameters); Fu"@)xw/-q
} ;1L7+.A
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publicList find(finalString query){ D}L4uz?
return getHibernateTemplate().find nCPIpw,]M
q a}=p
(query); u\P)x~-TM
} }W$}blbp
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publicList find(finalString query, finalObject _ .%\czO
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parameter){ b:}`O!UBw
return getHibernateTemplate().find _r}oYs%1
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(query, parameter); ~OXC6z
} X]Emz"
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public PaginationSupport findPageByCriteria q(Y<cJ?X
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(final DetachedCriteria detachedCriteria){ *My? l75
return findPageByCriteria O\T
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?zKVXK7}0
} FV/X&u8~
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public PaginationSupport findPageByCriteria g]V}azLr
$;_'5`xs
(final DetachedCriteria detachedCriteria, finalint k})Ag7c
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startIndex){ $.}fL;BzVz
return findPageByCriteria _1c'~;
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(detachedCriteria, PaginationSupport.PAGESIZE, S zOB{
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startIndex); MjG=6.J|`
} aT F}
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public PaginationSupport findPageByCriteria kRskeMr:Rd
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(final DetachedCriteria detachedCriteria, finalint iLy}G7h
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pageSize, (^eSm]<
finalint startIndex){
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return(PaginationSupport) K/G|MT)
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getHibernateTemplate().execute(new HibernateCallback(){ T"t3e=xA
publicObject doInHibernate xrO:Y!C?
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(Session session)throws HibernateException { Iq_cs
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Criteria criteria = Og%qv
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detachedCriteria.getExecutableCriteria(session); ~LHG
int totalCount = @g""*T1:$
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((Integer) criteria.setProjection(Projections.rowCount suaTXKjyk+
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()).uniqueResult()).intValue(); E<'3?(D9hL
criteria.setProjection ;04doub
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(null); vhZpYW8
List items = ?bQ~+M\
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criteria.setFirstResult(startIndex).setMaxResults NXDdU^w7B
sju. `f>-r
(pageSize).list(); N(]6pG=
PaginationSupport ps = jRXByi=9
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new PaginationSupport(items, totalCount, pageSize, \8=>l?P
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startIndex); o{?s\)aBa
return ps; (5;w^E9*n;
} \NS\>Q+d
}, true); &I:5<zK{
} ]k]P (w
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public List findAllByCriteria(final :Y0*P
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DetachedCriteria detachedCriteria){ 8{@|M l
return(List) getHibernateTemplate c@~\ FUr
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().execute(new HibernateCallback(){ {b"V7vn,
publicObject doInHibernate bwqla43gX
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(Session session)throws HibernateException { O2q`2L~
Criteria criteria = -k|r#^(G2
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detachedCriteria.getExecutableCriteria(session); S
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return criteria.list(); BEx?
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} sikG}p0mx<
}, true); CQW#o_\
} "e0$/WQ6J
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public int getCountByCriteria(final S2kFdx*Zf
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DetachedCriteria detachedCriteria){ [DC8X P5<
Integer count = (Integer) A/|To!R
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getHibernateTemplate().execute(new HibernateCallback(){ ?"N,do
publicObject doInHibernate t4/d1qW0
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(Session session)throws HibernateException { y$Sn3_9 V
Criteria criteria = B+#!%J_
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detachedCriteria.getExecutableCriteria(session); b
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return )gYsg
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criteria.setProjection(Projections.rowCount @#hd8_)A.
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()).uniqueResult(); W,9. z%
} Q0K2md_%x
}, true); S}f3b N
return count.intValue(); <^c?M[j
} Uoe;4ni
} 3gV
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用户在web层构造查询条件detachedCriteria,和可选的 Q>Voa&tYn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 M3P\1
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PaginationSupport的实例ps。 }Q&zYC]d
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ps.getItems()得到已分页好的结果集 v EppkS U1
ps.getIndexes()得到分页索引的数组 {9:[nqX
ps.getTotalCount()得到总结果数 zGzeu)d
ps.getStartIndex()当前分页索引 fy]z<SPhVJ
ps.getNextIndex()下一页索引 Wi7!J[ B
ps.getPreviousIndex()上一页索引 [PG#5.jwQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,~8&0p
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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 ~dc
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一下代码重构了。 T{WJf-pI
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我把原本我的做法也提供出来供大家讨论吧: hk*@<ff
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首先,为了实现分页查询,我封装了一个Page类: +az=EF
java代码: kPRG^Ox8e
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/*Created on 2005-4-14*/ \7V[G6'{
package org.flyware.util.page; r4MPs-}oF
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/** y26?>.!
* @author Joa c"*xw8|
* (V(8E%<c
*/ H8!;
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publicclass Page { shkyN
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/** imply if the page has previous page */ =Ju%3ptH0
privateboolean hasPrePage; _ASyGmO{
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/** imply if the page has next page */ 62.)fCQ^
privateboolean hasNextPage; Z Jgy!)1n
} *:H\GL
/** the number of every page */ F[q)ME+`)
privateint everyPage; 0{^ 0>H0
F+<e9[
/** the total page number */ sq rY<@%
privateint totalPage; E"<-To
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/** the number of current page */ *-eDUT|O
privateint currentPage;
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/** the begin index of the records by the current 'O^<i`8U]
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query */ "}Oj N\
privateint beginIndex; ZH)thd9^b
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s 9n_s=w
/** The default constructor */ 4N(iow4
public Page(){ R ~? 9+
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} \R[f< K%
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/** construct the page by everyPage HSj=g}r
* @param everyPage rVM?[_'O
* */ ne|N!!Dmk
public Page(int everyPage){ KY+BXGW*
this.everyPage = everyPage; 9j>LU<Z
} _/z3QG{Ea^
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/** The whole constructor */ 4 3G2{
public Page(boolean hasPrePage, boolean hasNextPage, FT6~\9m(
IFbN ]N0
b *Ca*!
int everyPage, int totalPage, S0WKEv@Hn
int currentPage, int beginIndex){ iE#I^`^V
this.hasPrePage = hasPrePage; bScW<DZJ-
this.hasNextPage = hasNextPage; 1StaQUB
this.everyPage = everyPage; KkZS 6rD\
this.totalPage = totalPage; -Mzm~@_s]
this.currentPage = currentPage; (9KiIRN
this.beginIndex = beginIndex; i4\DSQJ
} TG6E^3a P
xM_+vN*(
/** c,Yd#nokC
* @return 8Z>=sUMQ
* Returns the beginIndex. &~"e["gF=
*/ &%;K_asV;
publicint getBeginIndex(){ ^Is#_Z|
return beginIndex; o)+Uyl
} P"a9+ti+'
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/** s:*" b'
* @param beginIndex 2h#_n'DV
* The beginIndex to set. j4+kL4M@H
*/ Cznp(z
publicvoid setBeginIndex(int beginIndex){ v5 I}a7
this.beginIndex = beginIndex; O0QK `F/)*
} i\C~]K~O!
N*'d]P2P`J
/** 9uW\~DwsZ%
* @return /{!?e<N>
* Returns the currentPage. w0,rFWS
*/ =j~Xrytn
publicint getCurrentPage(){ vJsx_i\i
return currentPage; )26_7.|
} "p"~fN
/I9
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/** c52S2f7
* @param currentPage Q6hWHfS
* The currentPage to set. '\R/-.
*/ 6MmkEU z
publicvoid setCurrentPage(int currentPage){ %ql2 XAY
this.currentPage = currentPage; ,rWej;CzN
} Yl"l|2
:
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/** #_'|
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* @return d7qYz7=d
* Returns the everyPage. uolEX+
*/ 2Z7r ZjXW
publicint getEveryPage(){ l g*eSx>M
return everyPage; !@9G9<NK
} a$]i8AeG
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/** $m;DwlM
* @param everyPage ':DLv{R
* The everyPage to set. L[O.]2
*/ |%12Vr]J
publicvoid setEveryPage(int everyPage){ 0 ![
this.everyPage = everyPage; hYSf;cG}A
} ?+?`Jso(
@<C<rB8R
/** j S<."a/n
* @return HD153M,
* Returns the hasNextPage. rixt_}aE
*/ ;CLOZ{
publicboolean getHasNextPage(){ <L+y
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return hasNextPage; L<Q>:U.@\
} nP#|JRn=
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/** 6 B*,Mu4A
* @param hasNextPage I6rB_~]h
* The hasNextPage to set. 10{zF_9yx
*/ G!.%Qqs
publicvoid setHasNextPage(boolean hasNextPage){ ]B3f$;W
this.hasNextPage = hasNextPage; 9;R'Xo=y
} vY!'@W
GDY=^r
/** WnL7 A:sZ
* @return o+F<
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* Returns the hasPrePage. nj6|WJ
*/ zy'cf5k2
publicboolean getHasPrePage(){ fzjAP7 y
return hasPrePage; -^$`5Rk
} PdSYFJM
$u%7]]Y^\
/** qaiR329fx
* @param hasPrePage "I0F"nQ
* The hasPrePage to set. {8T/;K@
*/ )<[)7`
publicvoid setHasPrePage(boolean hasPrePage){ @@d6,=
this.hasPrePage = hasPrePage; )6*)u/x:
} SSysOeD+
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/** q#\4/Dt
* @return Returns the totalPage. .>
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* /Suh&qw>
*/ GS+Z(,J>=
publicint getTotalPage(){ 8 DPn5E#M1
return totalPage; Y+ !z]S/x
} Sy"!Q%+|
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/** GD0Q`gWNe
* @param totalPage G_S2Q @|Q
* The totalPage to set. fVz0H1\J&
*/ =fK6P6'B
publicvoid setTotalPage(int totalPage){ +*Zjo&pc
this.totalPage = totalPage; M`p[ Zq
} B3&C=*y
kK/([!
} /~3kkM(Ty
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nrKir
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Xx1e SX
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个PageUtil,负责对Page对象进行构造: EIF"{,m
java代码: i-,_:z=J
p4vX3?&1W
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/*Created on 2005-4-14*/ _b9>ZF~
package org.flyware.util.page; I lZ$Jd
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import org.apache.commons.logging.Log; Y2}m/7aF
import org.apache.commons.logging.LogFactory; E| y
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/** RV),E:?
* @author Joa X*t2h3"}
* L[tq@[(IJ
*/ #N'bhs
publicclass PageUtil { F#a'N c9
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privatestaticfinal Log logger = LogFactory.getLog |LirjC4
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*
(PageUtil.class); V^< Zs//7
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/** "EnxVV
* Use the origin page to create a new page XA\wZV
|{
* @param page l:*.0Tj
* @param totalRecords Iz8gZ:rd0
* @return 4A)_D{(SH
*/ 8aTo
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publicstatic Page createPage(Page page, int f1q0*)fk
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totalRecords){ 6L3i
return createPage(page.getEveryPage(), 9yp'-RKjw
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page.getCurrentPage(), totalRecords); $V;0z~&!'
} 5ljEh -
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/** 3x>Y
* the basic page utils not including exception W!JEl|]
/|@~:5R5H
handler ;&XC*R+
* @param everyPage VyWzb
* @param currentPage .gY=<bG/fA
* @param totalRecords T>w;M?`9K
* @return page .@psW0T%
*/ Gm=e;X;r
publicstatic Page createPage(int everyPage, int .:=5|0m
Wm/0Pi
currentPage, int totalRecords){ p5J!j I=
everyPage = getEveryPage(everyPage); Y^eF(
currentPage = getCurrentPage(currentPage); fDAT#nlyp
int beginIndex = getBeginIndex(everyPage, }brBhe8a
s?PB ]Tr
currentPage);
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int totalPage = getTotalPage(everyPage, r ?z}TtDp
fni7HBV?
totalRecords); I2z6iT4nB
boolean hasNextPage = hasNextPage(currentPage, R#!Urhh
@>`qfy?
totalPage); B^/(wHBp
boolean hasPrePage = hasPrePage(currentPage); ]j]<CqG
0@RVM|
returnnew Page(hasPrePage, hasNextPage, .dj}y
jd]f
everyPage, totalPage, s` =&l
currentPage, 9&{HD
m,&2s-v
beginIndex); R| XD#bG
} ON"p^o>/_?
.x1.` Y
privatestaticint getEveryPage(int everyPage){ hHgH'
return everyPage == 0 ? 10 : everyPage; Uurpho_~
} #JR$RH
7Ac.^rv5
privatestaticint getCurrentPage(int currentPage){ YTg8Zg-Z
return currentPage == 0 ? 1 : currentPage; E5\>mf
,;u
} !w/]V{9`X
Ss:'HH4
privatestaticint getBeginIndex(int everyPage, int DPfN*a-P(
lU.aDmy<
currentPage){ \/9 O5`u*V
return(currentPage - 1) * everyPage; E,QD6<?[
} s\(@f4p
O~Svk'.)
privatestaticint getTotalPage(int everyPage, int -i]2b
cL4Xh|NBp
totalRecords){ 1*:BOoYx
int totalPage = 0; pL: r\Y:R
]ClqX;'weJ
if(totalRecords % everyPage == 0) "ZuA._
totalPage = totalRecords / everyPage; =-avzuy#
else [@ NW
totalPage = totalRecords / everyPage + 1 ; @*WrHoa2N
n{=Ot^
";
return totalPage; ~|ha91
} ktM7L{Nz
)Jh:~9L%='
privatestaticboolean hasPrePage(int currentPage){ w8F`RRHEE
return currentPage == 1 ? false : true; 4}0Ry\
6
} 67U6`9d
NleMZ
privatestaticboolean hasNextPage(int currentPage, O2/_$i[F
7_J0[C!G
int totalPage){ }\1IsK~P
return currentPage == totalPage || totalPage == {uxTgX
QFFFxaeJg
0 ? false : true; xrkR)~ E
} !1l~'/r
O"wo&5b_
'Jd*r(2d
} XJ1Bl
Rpj{!Ia
"oh;?gQ.
\/-4 jF:
>uFFTik
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 I~nz~U:ak
{9{PU&?(
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 UYzNaw4/x
cGlpJ)'-{
做法如下: @Thrizh
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 yTf/]H]d
@S 0mNA
的信息,和一个结果集List: Hxn#vAc
java代码: q9c-UQB(!
TgKSE1
,:0!+1
/*Created on 2005-6-13*/ t+M'05-U2
package com.adt.bo; Uy?X-"UR
6=Sz5MC
import java.util.List; i?,\>LTG
iu2O/l#r
import org.flyware.util.page.Page; OF,_6"m
_>3#dk
/** 5x!rT&!G
* @author Joa bm h@SB
*/ #"C!-kS'=
publicclass Result { VO /b&%
2'Raj'2S4
private Page page; bGK-?BE5+A
|hX\ep
private List content; .pH 4[~
u/xP$
/** 9%riB/vkrF
* The default constructor =L`PP>"rW
*/ l~[
K.p&
public Result(){ 'C @yJf
super(); + -rSO"nc
} zoBp02j
8C*xrg#g:
/** (%G>TV
* The constructor using fields {c7@`AV]
* uWi pjxS
* @param page bAUYJPRpy
* @param content -s^cy+jd
*/ %}unlSTPP
public Result(Page page, List content){ %VE FruM
this.page = page; `%~f5<
this.content = content; ,+x\NY2d
} HUbXJsSP
8E>2
6@.
/** G]dHYxG
* @return Returns the content. F*Ul#yX
*/ ^ '_Fd
publicList getContent(){ Hi U/fi`
return content; .~a8\6t
} $4kbOqn4
n.,ZgLx["
/** 4$4Tx9C
* @return Returns the page. N9vNSmm
*/ AP9\]qZ(7
public Page getPage(){ |aj]]l[@S
return page; K3&k+~$
} mA#^Pv*
I]~s{I(EK
/** h}}7_I9
* @param content #nKGU"$+
* The content to set. c~6ywuq+M`
*/ TC
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public void setContent(List content){ l a_
this.content = content; &fnfuU$
} [p)2!]y
WK.,q>#
/** @Q:?,
* @param page aZmbt,.V
* The page to set. 5!6}g<z&L
*/ Iapzh y2l
publicvoid setPage(Page page){ o
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this.page = page; 4 ijZQ
} }~#qDrK
} NNRKYdp,
K81&BVx/
W#^p%?8pR
8
;=?Lw?
UQtG<W]<
2. 编写业务逻辑接口,并实现它(UserManager, uW,rmd
H$&P=\8n
UserManagerImpl) i^/H>E%u
java代码: >
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?
u#Uc6? E
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/*Created on 2005-7-15*/ k59.O~0V
package com.adt.service; o2LUB)=R'
%5<t3H"
import net.sf.hibernate.HibernateException; tNW0 C]
;fv/s]X86I
import org.flyware.util.page.Page; 4_\]zhS
'9 <APUyu
import com.adt.bo.Result; KYFkO~N
@'S !G"\
/** xCm`g{
* @author Joa 8V:yOq10
*/ w"j [c#vM
publicinterface UserManager { VHU,G+ms
v=+> ids
public Result listUser(Page page)throws }5ONDg(I~
Q__1QUu
HibernateException; O[&G6+
Lmyw[s\U
} \"A~ks~
79MB_Is]s
:*lB86Ly
Ea3 4x
.{k^
tf4
java代码: j'FBt8P'
$RV'DQO
[Uu!:SZ
/*Created on 2005-7-15*/ <}Rr C#uiA
package com.adt.service.impl; Q,xKi|$r
-o0~xspF
import java.util.List; ,0[h`FN
!8>tT
import net.sf.hibernate.HibernateException; =nN&8vRH
V9kL\Ys
import org.flyware.util.page.Page; <rF Y$
?x
import org.flyware.util.page.PageUtil; _ ;_NM5
}))JzrqAe
import com.adt.bo.Result; HzF]hm,
import com.adt.dao.UserDAO; m.N/g,
import com.adt.exception.ObjectNotFoundException; q9c:,k
import com.adt.service.UserManager; g4*]R>f
Y vjRJ
/** w`Js"_\
* @author Joa S[cVoV
*/ iw^(3FcP@C
publicclass UserManagerImpl implements UserManager { ^++ec>
gb_k^wg~1'
private UserDAO userDAO; &U8W(NxN
E`SFr
/** 38T2IN
* @param userDAO The userDAO to set. E6d0YgfD
*/ r z%=qY
publicvoid setUserDAO(UserDAO userDAO){ nzHsyL
this.userDAO = userDAO; /Hl]$sJY
} C0F#PXUy
&Rx-zp&dJ
/* (non-Javadoc) SD^6ib/]b
* @see com.adt.service.UserManager#listUser T6ajWUw
D=nuK25
(org.flyware.util.page.Page) jz2W/EE`w
*/ )5U&^tJ
public Result listUser(Page page)throws qwU,D6
V{[vIt*
HibernateException, ObjectNotFoundException { VL/%D*
int totalRecords = userDAO.getUserCount(); ~cSOni`
if(totalRecords == 0) 9+\3E4K
throw new ObjectNotFoundException W=Ru?sG=
RvF6bIqo
("userNotExist"); it~>)_7*P
page = PageUtil.createPage(page, totalRecords); eJrJ5mlI`
List users = userDAO.getUserByPage(page); T&=1IoOg
returnnew Result(page, users); X|F([,o
} {g *kr1JM
F$FCfP7
} %<q l
Y.qlY3iBp
7)NQK9~
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$gN1&K
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 UNJ]$x0
YN
~7 nOw
询,接下来编写UserDAO的代码: sW B;?7P
3. UserDAO 和 UserDAOImpl: 7
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java代码: uJ4RjLM`
E3\O?+h#
Z;aQ/n[`
/*Created on 2005-7-15*/ Pgs^#(^>
package com.adt.dao; QUp()B1
YB h:
import java.util.List; Oc;0*v[I
gg(^:`+
import org.flyware.util.page.Page; *K6 V$_{S
=~% B}T
import net.sf.hibernate.HibernateException; [EDw0e
Y%b
5{1
/** `Njv#K} U
* @author Joa =j 6amk-
*/ 93yJAao9
publicinterface UserDAO extends BaseDAO { i8w(G<Y=
&_
Ewu@4
publicList getUserByName(String name)throws ysfR@ sH7
iKa}@U
HibernateException; ^{["]!f#
wxARD3%
publicint getUserCount()throws HibernateException; .}6 YKKqS
h3D8eR.
publicList getUserByPage(Page page)throws . \*Z:
lztPexyXZ
HibernateException; *usfJ-
I.j`h2
} pJx88LfR
gEtDqq~y@
S=^yJ6xJ
.
zvF!!z
~zFs/(k
java代码: }`4o+
t<9oEjk["
L@w|2
/*Created on 2005-7-15*/ I+w3It
package com.adt.dao.impl; WEUr;f
)+Wx!c,mb
import java.util.List; FGBPhH% (8
=Z iyT$p
import org.flyware.util.page.Page; D Y($
+/7UM x1
import net.sf.hibernate.HibernateException; )h,+>U@
import net.sf.hibernate.Query; 'Zf_/y
/yyed{q
import com.adt.dao.UserDAO; X^#48*"a
~Rk%M$E9
/** Ooz+V;#Q
* @author Joa )MLOYX
*/ RyC]4QyC
public class UserDAOImpl extends BaseDAOHibernateImpl (1%u`#5n-N
dl@
implements UserDAO { s"p}>BjMIC
I 6a{'c(P
/* (non-Javadoc) afv?z
* @see com.adt.dao.UserDAO#getUserByName j/{F#auI
U^?/nRZ
(java.lang.String) ouK&H|'
*/ :S0r)CNP
publicList getUserByName(String name)throws xaX3<V@S
lz
EF^6I
HibernateException { (ta!4h,
String querySentence = "FROM user in class
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Axhe9!Fm
com.adt.po.User WHERE user.name=:name"; +,9I3Dq
Query query = getSession().createQuery 9`i=kp
%+ig7a:
(querySentence); hAHl+q)w?
query.setParameter("name", name); CtV$lXxup
return query.list();
pMYEL
} ,Ww)>O+
5Y#yz>B@ ]
/* (non-Javadoc) muo(bR8
* @see com.adt.dao.UserDAO#getUserCount() 1`r
4
*/ >,Zjlkh3
publicint getUserCount()throws HibernateException { pvQw+jX
int count = 0; ;hJTJMA6/6
String querySentence = "SELECT count(*) FROM .%<oy"_
v$s3f|Y
user in class com.adt.po.User"; ,h5\vWZ
Query query = getSession().createQuery o"R[#E&Yx
4K[ E3aA
(querySentence); mEv<r6qDT
count = ((Integer)query.iterate().next R5NDT4QYU
?P,z^
()).intValue(); J "yO\Y
return count; 3bu VU&ap
} Oj\lg2Ck
$Lv,e\]
/* (non-Javadoc) jxL}tS{j
* @see com.adt.dao.UserDAO#getUserByPage z4b2t}
[U]U *x
(org.flyware.util.page.Page) H ifKa/}P8
*/ aB0L]i
publicList getUserByPage(Page page)throws wUW^
O
Xa=oryDt
HibernateException { *%7 [{Loz
String querySentence = "FROM user in class %/"I.\%d
q,F\8M\$
com.adt.po.User"; ST5L
O#5
Query query = getSession().createQuery Hdw;=]-
I'HPy.PV
(querySentence); $~!%Px)
query.setFirstResult(page.getBeginIndex()) i#Io;
.setMaxResults(page.getEveryPage()); x^Q:U1
return query.list(); 9Bvi2
3
} R8I%Cyc
L15?\|':Y
} >!848J
f(:+JH<P~
a\>+!Vq
y$|%K3
T\I}s"d
至此,一个完整的分页程序完成。前台的只需要调用
4~xKW2*`K
g5M=$y/H
userManager.listUser(page)即可得到一个Page对象和结果集对象 h/ 5|3
a?S5 =
的综合体,而传入的参数page对象则可以由前台传入,如果用 DXBc 7J
1AQVj]#S
webwork,甚至可以直接在配置文件中指定。 w=:o//~6j
LvtHWt
下面给出一个webwork调用示例: IR;l{q&`
java代码: SW5V:|/
5;'(^z-bL
ze2%#<
/*Created on 2005-6-17*/ 7irpD7P>
package com.adt.action.user; ;\j7jz^uC
B-^r0/y;
import java.util.List; %"-bG'Yc
} I>6 8dS[
import org.apache.commons.logging.Log; ?M!Mb-C[
import org.apache.commons.logging.LogFactory; p3r("\Za,
import org.flyware.util.page.Page; p0*qv"lA
QO2@K1Y
import com.adt.bo.Result; ;)~}/nR<a
import com.adt.service.UserService; JLd-{}A""-
import com.opensymphony.xwork.Action; fi%)520
"&Hr)yyWG
/** SR%k|YT
* @author Joa y0vJ@ %`
*/ yFoPCA86y
publicclass ListUser implementsAction{ e"oTlB
4)"S/u
privatestaticfinal Log logger = LogFactory.getLog PRJ
\SSHj ONX
(ListUser.class); QB
uX#bDV
[ Y+Ta,
private UserService userService; wE[gp+X~
P ~ :
N
private Page page; RW{y.WhB
p{
Xde
privateList users; IR2=dQS
O&dBLh!G
/* clG@]<a`_
* (non-Javadoc) OZc4 -5
* u6nO\.TTtY
* @see com.opensymphony.xwork.Action#execute() )J*M{Gm 6i
*/ XGuxd
publicString execute()throwsException{ pMHF u/|Pr
Result result = userService.listUser(page); InI>So%e|<
page = result.getPage(); 2FR+Z3&z
users = result.getContent(); _01wRsm%2
return SUCCESS; m"@o
} 1:JwqbZKJ
iYZn`OAx
/** Ul_5"3ze
* @return Returns the page. 7nm'v'\u+V
*/ ?7>"ZGDe>
public Page getPage(){ ]]0Yh
return page; Fw\g\
} Oa2\\I
[~PR\qm
/** 0kSM$D_
* @return Returns the users. o\F>K'
*/ q{&\nCy
publicList getUsers(){ LSo*JO6
return users; p}3` "L=
} Nm
!~h|3
O6/:J#X%
/** N>Ih2>8t
* @param page iciKjXJ:
* The page to set. %3O))Ug5
*/ ufCpX>lNF
publicvoid setPage(Page page){ p^|6 /b
this.page = page; w
>2sr^!y
} IITUM)
}K8e(i6z
/** 5F+G8
* @param users OLPY<ax
* The users to set. Ml$<x"Q
*/ QyxUK}6mr
publicvoid setUsers(List users){ V3#ms0
this.users = users; 1
_Oc1RM
} N2k<W?wQ
O!%T<2i3
/** J^`5L7CO
* @param userService 3:MJKS02OD
* The userService to set. WPkKbF
*/ ax>j3HKi
publicvoid setUserService(UserService userService){ $&&E[JY
this.userService = userService; CvmIDRP*
} M,S'4Szuk
} :^Pks R
j{YYG|
CxeW5qc
qxb]UV,R
2?GMKd)
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, njf\fw_
('SId@
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 h#"$W;(
*s*Y uY%y
么只需要: ?9a%g\`?:
java代码: 1Vdi5;dn
/ n_s"[I4
RzjUrt
<?xml version="1.0"?> ] re=8s6
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork HB8s[]A:D
sde>LZet/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q6)fP4MQ]
gr SF}y!3
1.0.dtd"> N"G aQ
29,ET}~
<xwork> 4_kN';a4Q
\O;2^
<package name="user" extends="webwork- LXK!4(xa W
0mujf
interceptors"> 8^>c_%e}
OQ&N]P2p
<!-- The default interceptor stack name R,G*]/r`
NC%hsg^0/
--> Y@0'0
<default-interceptor-ref Mg.%&vH\
~2"hh$
name="myDefaultWebStack"/> B={_}f
]alc%(=
<action name="listUser" HCs^?s8Pp
o,`"*][wd
class="com.adt.action.user.ListUser"> l,7&
z
<param /ooGyF
f\<r1
name="page.everyPage">10</param> e4tIO
<result Nnl3r@
+:.Jl:fx4
name="success">/user/user_list.jsp</result> 2+gbMd4n
</action> +7H)s
sQa;l]O:NC
</package> js<d"m*
dtC@cK/,D
</xwork> 6P1s*u
TVD~Ix
U =.PL\
^)Hf%
0N,<v7PX
_]`7et\=
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 H2s:M
g#J aw|N
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。 2!^=G=H/
\)6glAtN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
e^Zm09J
=%X."i1A
}=^ ,c
c* {6T}VZr
I}4
PB+yu
我写的一个用于分页的类,用了泛型了,hoho I\.|\^
zqeQ
java代码: 86r"hy~
Z+El(f x
<b:%o^
package com.intokr.util; Hb=#`
jSY[Y:6md
import java.util.List; VsQ|t/|#
] 3{t}qY$A
/** Sa= tiOv
* 用于分页的类<br> N(&{~*YE
* 可以用于传递查询的结果也可以用于传送查询的参数<br> f^$,;
* Hf`i~6
* @version 0.01 GJ,&$@8)
* @author cheng 3f7zW3F
*/ =?RI`}vw_H
public class Paginator<E> { =_dM@ j
privateint count = 0; // 总记录数 ^[?y 2A:
privateint p = 1; // 页编号
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privateint num = 20; // 每页的记录数 (9]Uuvfp6"
privateList<E> results = null; // 结果 "\b>JV5
RQ,#TbAe
/** Je6[q
* 结果总数 2Vx4"fHP#N
*/ y(COB6r
publicint getCount(){ Pd91<L
return count; z#tIa
} iq; |
i!
75# 8P?i
publicvoid setCount(int count){ g&$=Y7G
this.count = count; tIuM9D{P
} *2/Jg'de
axC|,8~tq
/** 'c35%?]
* 本结果所在的页码,从1开始 Z.\q$U7'9
* ;I>nA6A
* @return Returns the pageNo. cJ4My#w
*/ cJo%j -AM
publicint getP(){ \O|SPhaIf
return p; 7Jn%XxHq
} ]Z!Y*v
#J[g
r_
/** C`.YOkpj
* if(p<=0) p=1 nrl?<4_
* ,h*gd^i
* @param p 7V"?o
*/ W'./p"2g
publicvoid setP(int p){ yYCS-rF>
if(p <= 0) 'UhoKb_p
p = 1; 8M5)fDu*?
this.p = p; $C[z]}iOi
} X7*F~LFrj
46C%at
M0}
/** 4Q|>k)H
* 每页记录数量 <o(;~
*/ t<!m4Yd|#
publicint getNum(){ fd)8lK[KJ"
return num; {T4_Xn -I
} /@9Q:'P
pv]@}+<Dt
/** g NI1W@)
* if(num<1) num=1
t ed:]
*/ zj`c%9N+
publicvoid setNum(int num){ ^#_gk uyd!
if(num < 1) C[^VM$
num = 1; uN%Cc12
this.num = num; y3oq{Z>
} |J&\/8Q
-nb U5o
/** "hyfo,r
* 获得总页数 AwJg/VBo)
*/ )M8d\]
publicint getPageNum(){ b^W&-Hh
return(count - 1) / num + 1; IL@yGuO,
} !:+U-mb*
tV++QC7@L
/** k\OZ'dS
* 获得本页的开始编号,为 (p-1)*num+1 xg p)G!
*/ 4&*lpl*N
publicint getStart(){ ~>:JwTy
return(p - 1) * num + 1; ZX_QnSNZ?
} mIlg=8:
?_]Y8f
/** q`e0%^U
* @return Returns the results. kepuh%KY[
*/ ().C
publicList<E> getResults(){ #/qcp|m
return results; iA[T'+.Y
} fG 2)r
oiyvKMHz7
public void setResults(List<E> results){ QytO0K5
this.results = results; ?1\5X<|,
} k5RzW4zq;
SzLlJUV X
public String toString(){ |r@;ulO
StringBuilder buff = new StringBuilder O@$>'Z
2-F7tcya|
(); xU\!UVQ/
buff.append("{"); !WyJ@pFU^
buff.append("count:").append(count); r6S
buff.append(",p:").append(p); TXB!Y!RG#
buff.append(",nump:").append(num); %<yW(s9{
buff.append(",results:").append r`"_D%kc
ev&l=(hY
(results); ]D6<6OB
buff.append("}"); {V[xBL
<
return buff.toString(); 'M%iS4b{IM
} }cz58%
.\bJ,of9
} dOD(<
lr&2,p<
AG >D,6Y