Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 P&0o~@`cL
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /9..hEq^
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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 drc]"6 k
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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 quEP"
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分页支持类: a.O pxd
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java代码: !uwZ%Uxz
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package com.javaeye.common.util; 4I97<zmrT
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import java.util.List; F}Kkhs
{
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publicclass PaginationSupport { u6#=<FD/}
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publicfinalstaticint PAGESIZE = 30; fI([vI
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privateint pageSize = PAGESIZE; |)pRkn8x
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privateList items; VX<jg #(
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privateint totalCount; <*4BT}r,^2
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privateint[] indexes = newint[0]; &rmXz6F
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privateint startIndex = 0; I}S~,4
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public PaginationSupport(List items, int g} /efE
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totalCount){ MY]<^/Q
setPageSize(PAGESIZE); L~PBD?l
setTotalCount(totalCount); j~Cch%%G
setItems(items); <HC5YA)4
setStartIndex(0); (-:lO{@FsC
} D;bHX
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public PaginationSupport(List items, int Pzl2X@{ %
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totalCount, int startIndex){ ipThwp9
setPageSize(PAGESIZE); ,sqxxq
setTotalCount(totalCount); AJ0
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setItems(items); ^DWvzfj
setStartIndex(startIndex); g$N/pg2>cT
} [10y 13
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public PaginationSupport(List items, int nbECEQ:|B
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totalCount, int pageSize, int startIndex){ kU
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setPageSize(pageSize); 5@kNvi
setTotalCount(totalCount); ZVin+ z
setItems(items); +6$ |No
setStartIndex(startIndex); 'fGB#uBt
} $gv3Up"U
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publicList getItems(){ ,@#))2<RK
return items; ]#fmih^
} |*T3TsP u
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publicvoid setItems(List items){ RiPxz=kr
this.items = items; !)1gGXRY
} M:9
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publicint getPageSize(){ '[z529HN
return pageSize; Z?);^m|T
} o;zU;pkB
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publicvoid setPageSize(int pageSize){ |K(2_Wp
this.pageSize = pageSize; jgW-&nK!
} vo]!IY
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publicint getTotalCount(){ 5x=aJl;G
return totalCount; @5rl;C
} VPh0{(O^=
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publicvoid setTotalCount(int totalCount){ j^Vr!y
if(totalCount > 0){ @X?7a]+;8
this.totalCount = totalCount; x/B1\U
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int count = totalCount / UK7pQt}9
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pageSize; S /kM#
if(totalCount % pageSize > 0) 4*D'zJsJ
count++; $\w<.)"#
indexes = newint[count]; <Pm!#)-g9
for(int i = 0; i < count; i++){ b:M1P&R
indexes = pageSize * /Z ?$!u4I
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i; &qjc+-r{l
} 1z6$>{FUR
}else{ wOLDHg_
this.totalCount = 0; jGSY$nt9
} i eL7jN,'m
} ]VCVV!G_=n
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publicint[] getIndexes(){ _&wrA3@/L
return indexes; 2d# 3LnO
} Q:5^K
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publicvoid setIndexes(int[] indexes){ bih%hqny
this.indexes = indexes; dKk#j@[n"
} N*w6D:
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publicint getStartIndex(){ X"k:+
return startIndex; u{'|/g&
} Km)VOX[ZZ
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publicvoid setStartIndex(int startIndex){ hb. ^&
if(totalCount <= 0) IrMUw$
this.startIndex = 0; 44x+2@&1
elseif(startIndex >= totalCount) sc0.!6^'V
this.startIndex = indexes =.48^$LWx
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[indexes.length - 1]; q^ w@l
elseif(startIndex < 0) E
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this.startIndex = 0; }mYxI^n
else{ 7K 'uNPC
this.startIndex = indexes ;(3!#4`q(]
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[startIndex / pageSize]; K7-z.WTUR
} 8)o%0#;0B
} J85S'cwZZ
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publicint getNextIndex(){ !0Mx Bem
int nextIndex = getStartIndex() + cSD$I^$oq
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pageSize; j6: jN-z
if(nextIndex >= totalCount) yp!7^
return getStartIndex(); A/c #2
else k6$Ft.0d1Z
return nextIndex; RD|DHio%
} }`~n$OVx
_yRD*2 !;
publicint getPreviousIndex(){ @dyh:2!
int previousIndex = getStartIndex() - &E+mXEve
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pageSize; 'nT#c[x[0
if(previousIndex < 0) QG=K^g
return0; YctWSfh
else SYd6D@^2j
return previousIndex; U!\~LKfA
} xep8CimP'
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} UasU/Q <
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抽象业务类 *6bO2LO"
java代码: /os,s[w
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/** 2oo/KndU
* Created on 2005-7-12 9Wv}g"KY0
*/ (2ZkfN
package com.javaeye.common.business; [Qqomm.[\w
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import java.io.Serializable; RuGG3"|
import java.util.List; fgoLN\
ictV7)
import org.hibernate.Criteria; `k6ZAOQtX
import org.hibernate.HibernateException; .Im=-#EN
import org.hibernate.Session; "U-dw%b}b
import org.hibernate.criterion.DetachedCriteria; ,rS?^"h9
import org.hibernate.criterion.Projections; *>h|<|T'
import P?ms^
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org.springframework.orm.hibernate3.HibernateCallback; #:NY9.\o
import EeR} 34
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org.springframework.orm.hibernate3.support.HibernateDaoS ubv>*iO
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upport; w,az{\
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import com.javaeye.common.util.PaginationSupport; a*&(cn
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public abstract class AbstractManager extends {e5DQ 21.
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HibernateDaoSupport { bd\%K`JQ{
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privateboolean cacheQueries = false; yv|`A2@9
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privateString queryCacheRegion; K3iQ/j~a q
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publicvoid setCacheQueries(boolean 8'"=y}]H~
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cacheQueries){ EsS$th)d
this.cacheQueries = cacheQueries; P1R5}i
} 2){O&8 A
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publicvoid setQueryCacheRegion(String wF9L<<&B
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queryCacheRegion){ ~F^tLi!5
this.queryCacheRegion = M1icj~Jr
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queryCacheRegion; /i~x.i3
} zI0d
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publicvoid save(finalObject entity){ NBL%5!'
getHibernateTemplate().save(entity); H:)_;k
} @^Rl{p
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publicvoid persist(finalObject entity){ y 2)W"PuG
getHibernateTemplate().save(entity); 6e8 gFQ"w2
} .DI?-=p|_#
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publicvoid update(finalObject entity){ 2qot(Zs1i
getHibernateTemplate().update(entity); K3Bw3j 9
} d'"|Qg_'
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publicvoid delete(finalObject entity){ d
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getHibernateTemplate().delete(entity); !S%0#d2
} 1F_$[iIX]
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publicObject load(finalClass entity, ~yt 7L,OQ
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finalSerializable id){ >(-A"jf
return getHibernateTemplate().load *4e?y
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(entity, id); 16>D?;2o(
} wBvVY3VQ^
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publicObject get(finalClass entity, q|:wzdmNZ
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finalSerializable id){ $}AbR:z
return getHibernateTemplate().get Ia<V\$ #
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(entity, id); R+U$;r8l
} hbg$u$1`,
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publicList findAll(finalClass entity){ KZTLIZxI-
return getHibernateTemplate().find("from =@0J:"c
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" + entity.getName()); k qL.ZR
} 14"57Jt8
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publicList findByNamedQuery(finalString w|6/ i/X
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namedQuery){ vc&v+5Y
return getHibernateTemplate pY@QR?F\
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().findByNamedQuery(namedQuery); Pmo<t6
} :dh; @kp
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publicList findByNamedQuery(finalString query, tsJR:~
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finalObject parameter){ SAdE9L =d
return getHibernateTemplate ^?Mp(o
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().findByNamedQuery(query, parameter); D*ZjoU
} jLVG=rOn
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publicList findByNamedQuery(finalString query, a_V\[V{R=
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finalObject[] parameters){ s*[
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return getHibernateTemplate .whi0~i
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().findByNamedQuery(query, parameters); ]c~yMA+]FZ
} Uffwzd!
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publicList find(finalString query){ ",.f
return getHibernateTemplate().find D>[Sib/@
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(query); K<wFr-z
} Q(]m1\a
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publicList find(finalString query, finalObject ~t~[@2?WG
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parameter){ jwT` Z
return getHibernateTemplate().find gDVsi
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(query, parameter); P,ueLG=
} H oABo:
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public PaginationSupport findPageByCriteria C[<}eD4bV
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(final DetachedCriteria detachedCriteria){ %*}rLn"?
return findPageByCriteria Yr/$92(
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7%i'F=LzT
} ;ND$4$
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public PaginationSupport findPageByCriteria 2+rT .GFc
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(final DetachedCriteria detachedCriteria, finalint 8&G9 ?n`I5
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startIndex){ S(Af o`
return findPageByCriteria |E7J5ha
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(detachedCriteria, PaginationSupport.PAGESIZE, ZK8)FmT_<O
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startIndex); Q-'j131[
} J)>DsQ+Cj
} +}nrJv
public PaginationSupport findPageByCriteria xqzeBLU
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(final DetachedCriteria detachedCriteria, finalint @01.Pd
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pageSize, Dj(PH3^
finalint startIndex){ bRxI7 '
return(PaginationSupport) Ze~P6
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate ^)~Smj^d
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(Session session)throws HibernateException { 'vd&r@N
Criteria criteria = 5G}4z>-]F)
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detachedCriteria.getExecutableCriteria(session); {&n- @$?
int totalCount = zsXgpnlHT
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((Integer) criteria.setProjection(Projections.rowCount 3p=Xv%xd
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()).uniqueResult()).intValue(); k9}8xpH
criteria.setProjection -U /)y:k!%
1 %P-X!
(null); (N9-YP?qm
List items = JB~^J5#[Oh
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criteria.setFirstResult(startIndex).setMaxResults KSPa2>lz?
gB'ajX=OA/
(pageSize).list(); y''~j<'
PaginationSupport ps = ayA;6Qt
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new PaginationSupport(items, totalCount, pageSize, V1]GOmXz
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startIndex); Zo<)r2|O.
return ps; <a"(B*bBd
} U3{<+vSR`
}, true); LeLUt<4~
} jw:z2:0~
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public List findAllByCriteria(final ]eKuR"ob0
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DetachedCriteria detachedCriteria){ 4=^_VDlpd
return(List) getHibernateTemplate ~S/oW89
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().execute(new HibernateCallback(){ XPX?+W=mv
publicObject doInHibernate (SyD)G\rj
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(Session session)throws HibernateException { Hh1_zd|
Criteria criteria = XGB\rfvS
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detachedCriteria.getExecutableCriteria(session); e_=K0fFz
return criteria.list(); @wR3L:@
} *6/IO&y1a
}, true); B>fZH\Y
} y0d=
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public int getCountByCriteria(final ,m=G9QcN
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DetachedCriteria detachedCriteria){ )q=F_:$
Integer count = (Integer) Z\nDR|3
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getHibernateTemplate().execute(new HibernateCallback(){ vha9,5_
publicObject doInHibernate xsH1)
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(Session session)throws HibernateException { |T|m5V'l
Criteria criteria = mXRkR.zu+
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detachedCriteria.getExecutableCriteria(session); 1,fR kQ
return r^~+<"
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criteria.setProjection(Projections.rowCount (03/4*g_s
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()).uniqueResult(); XRV]u|w=g
} CPOHqK`k
}, true); XQy`5iv
return count.intValue(); zV&l^.
} 9^}&PEl
} v$]B;;[A
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用户在web层构造查询条件detachedCriteria,和可选的 t8*Jdd^3Z/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8gS7$ EH'
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PaginationSupport的实例ps。 zgwez$
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ps.getItems()得到已分页好的结果集 \l59/ZFan
ps.getIndexes()得到分页索引的数组 uN`/&_$c
ps.getTotalCount()得到总结果数 8qyEHUN2q
ps.getStartIndex()当前分页索引 &en.
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ps.getNextIndex()下一页索引 O&l4/RtQ\)
ps.getPreviousIndex()上一页索引 TDH^x1P
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \qG?'Iy
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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 p[Po*c.b
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一下代码重构了。 {:1j>4m2
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我把原本我的做法也提供出来供大家讨论吧: 1wR[nBg*|
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首先,为了实现分页查询,我封装了一个Page类: IXy6Yn9l
java代码: WE) *~5
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/*Created on 2005-4-14*/ }-oba_
package org.flyware.util.page; \|,| )
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/** uBlPwb,V
* @author Joa
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* '9}&@;-_
*/ 4LTm&+(5
publicclass Page { DPI[~
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/** imply if the page has previous page */ '7?Y+R@|L
privateboolean hasPrePage; x%EGxs;>^
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/** imply if the page has next page */ 4}H+hk8-
privateboolean hasNextPage; 8US#SI'x
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/** the number of every page */ r9ulTv}X
privateint everyPage; Dj\nsc@e3
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/** the total page number */ H,(vTthd
privateint totalPage; #~
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/** the number of current page */ c1Ks{%iA
privateint currentPage; Q!+AiSTU
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/** the begin index of the records by the current @62,.\F
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query */ 'zYS:W
privateint beginIndex; MJGT|u8O&
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/** The default constructor */ cUR :a@
public Page(){ gv`_+E{P
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} So1TH%
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/** construct the page by everyPage 'gf[Wjb,%
* @param everyPage z8X7Y
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* */ .y
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public Page(int everyPage){ [.}qi[=n
this.everyPage = everyPage; 1$0Kvvg[
} +pR,BjY
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/** The whole constructor */ =ANr|d
public Page(boolean hasPrePage, boolean hasNextPage, F!X0Wo=
@;4;72@O
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int everyPage, int totalPage, Ih.+-!w
int currentPage, int beginIndex){ ^77W#{ Zs
this.hasPrePage = hasPrePage; VEgtN}
this.hasNextPage = hasNextPage; ,8 4|qI
this.everyPage = everyPage; n[jXqFm!`
this.totalPage = totalPage; "u6pl);G
this.currentPage = currentPage; rDWAZ<;;
this.beginIndex = beginIndex; ogFo/TKM
} z 206fF
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/** vqeH<$WHvy
* @return *p(_="J,
* Returns the beginIndex. "L~Oj&AN[
*/ bLg!LZ|S0s
publicint getBeginIndex(){ U"r*kO%
return beginIndex; _WZx].|A=
} @[;'b$T$
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/** G=cRdiy`C
* @param beginIndex %E_Y4Oe1
* The beginIndex to set. +@rFbsyJ.
*/ 5=?P6I_$G
publicvoid setBeginIndex(int beginIndex){ hQ|mow@Zmz
this.beginIndex = beginIndex; m \)B=H!bz
} xrg"/?84
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/** AY52j
* @return i6#*y!3{
* Returns the currentPage. SMZ*30i
*/ p :xyy*I
publicint getCurrentPage(){ 2PQBUq
return currentPage; ZH
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} ')q0VaohC
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/** x Q"uC!Gu4
* @param currentPage q1VKoKb6\:
* The currentPage to set. T~xVHk1
*/ (u 7Lh>6%
publicvoid setCurrentPage(int currentPage){ 6y^
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this.currentPage = currentPage; \Eh5g/,[
} +ayC0
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/** J&aN6 l?
* @return c[-N A
* Returns the everyPage. 7rdmj[vu
*/ &| (K#|^@
publicint getEveryPage(){ "pDU v^ie
return everyPage; 2 ,nhs,FZ
} ={BC0,
i*|HN"!
/** @|:fm()
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* @param everyPage 8|Tqk,/pD
* The everyPage to set. :gsRJy1
*/ WXxnOLJr
publicvoid setEveryPage(int everyPage){ 2Z{?3mAb;
this.everyPage = everyPage; ,WE2.MWR
} `/WxEu3
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/** VrW]|jIu*
* @return }uDpf0;^
* Returns the hasNextPage. F$8:9eL,T
*/ bhUE!h<
publicboolean getHasNextPage(){ ~u*4k:2H
return hasNextPage; [k
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} 8U@f/P
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/** $ #!oejLD
* @param hasNextPage gOg7:VPG
* The hasNextPage to set. {gzQ/|}#z-
*/ CG%bZco((
publicvoid setHasNextPage(boolean hasNextPage){ mPA)G,^
this.hasNextPage = hasNextPage; GSRf/::I}4
} !PIg,
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/** 0gqV>:
* @return sO) H#G
* Returns the hasPrePage. a?W5~?\9
*/ eztK`_n
publicboolean getHasPrePage(){ QuS=^,]
return hasPrePage; 9po=[{Bp
} QP(d77n
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/** ;.jj>1=Tnl
* @param hasPrePage R_j.k3r4d
* The hasPrePage to set. KOg,V_(I
*/ o135Xh$_>'
publicvoid setHasPrePage(boolean hasPrePage){ i5 r<CxS
this.hasPrePage = hasPrePage; rT R$\ [C
} \Hb!<mrp
<J d!`$
/** jIaaNO)
* @return Returns the totalPage. /cClV"S*G
* T4W20dxL7
*/ 6OE
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publicint getTotalPage(){ 7z$53z
return totalPage; 'Qt[cW
} D<v<
:
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/** k:n{AoUc
* @param totalPage L/fXP@u
* The totalPage to set. ;*rGZ?%*
*/ V(cU/Aia^
publicvoid setTotalPage(int totalPage){ l8E))oz1T
this.totalPage = totalPage; t5 >ma:^j
} Ju>QQOxi|
dkg`T#}
} 1a9' *[
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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 0VvY(j:hp
PoZ$3V$(Lz
个PageUtil,负责对Page对象进行构造: fKEDe>B5
java代码: %(s|
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/*Created on 2005-4-14*/ yuC"V'
package org.flyware.util.page; `/1rZ#
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import org.apache.commons.logging.Log; QH><!
sa
import org.apache.commons.logging.LogFactory; VP< zOk7
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/** _9D]1f=&
* @author Joa e3n^$'/\r
* pKXSJ"Xo
*/ \ MuKS4
publicclass PageUtil { #HL$`&m
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privatestaticfinal Log logger = LogFactory.getLog X,@nD@
@j\;9>I/
(PageUtil.class); ;|T|*0vY[
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/** 3B[tbU(
* Use the origin page to create a new page dDiy_Q6
* @param page &pl)E$Y
* @param totalRecords <.g)?nj1
* @return "viZ"/~6
*/ xe OfofC(l
publicstatic Page createPage(Page page, int @/aJi6d"^E
bHq.3;
totalRecords){ ,h5 FX^
return createPage(page.getEveryPage(), *} *HXE5
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page.getCurrentPage(), totalRecords); Y<^Or
} Up-^km
?/}IDwuh
/** / !h<+
* the basic page utils not including exception K4Ed]hX
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handler (|O(BxS
* @param everyPage s4 ,`
* @param currentPage \B
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* @param totalRecords &: LE]w
* @return page /W>?p@j+K
*/ aIT0t0.
publicstatic Page createPage(int everyPage, int 0dx%b677d
@ #J2t#
currentPage, int totalRecords){ V#599-
everyPage = getEveryPage(everyPage); 0XE6Hw
currentPage = getCurrentPage(currentPage); JWu0VLo
int beginIndex = getBeginIndex(everyPage, 0(5qVJ12
3#fg
2
currentPage); b7'A5]X
int totalPage = getTotalPage(everyPage, cooicKS7
*W=1yPP
totalRecords); Qt"jU+Zoy
boolean hasNextPage = hasNextPage(currentPage, ko!]vHB9`
fZs}u<3Q)
totalPage); !j6CvclT
boolean hasPrePage = hasPrePage(currentPage); FBi&MZ`
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returnnew Page(hasPrePage, hasNextPage, 1.2qh"#
everyPage, totalPage, sNG 7fi.|
currentPage, O?#<kmd/)
=585TR;
V
beginIndex); 9u^za!pE
} ,~=+]9t
abVEi[nP
privatestaticint getEveryPage(int everyPage){ X.e4pLwGK
return everyPage == 0 ? 10 : everyPage; abe5 As r
} ME*zMLoF+
cor!S a>
privatestaticint getCurrentPage(int currentPage){ 2e,cE6r
return currentPage == 0 ? 1 : currentPage; (=%0x"'
} s7`2ky()kz
_B&;z $
privatestaticint getBeginIndex(int everyPage, int YqKQm+G
!y1qd
currentPage){ Ux);~P`/o
return(currentPage - 1) * everyPage; ZjK'gu8*
} @gx]3t*]I
YFcMU5_F
privatestaticint getTotalPage(int everyPage, int ]7,0}q.
Q9X+H4`}y
totalRecords){ it j&L <e
int totalPage = 0; fob.?ID-;
&)Vuh=
if(totalRecords % everyPage == 0) T~lHm
totalPage = totalRecords / everyPage; %
y` tDR
else 74Aecb{
totalPage = totalRecords / everyPage + 1 ; ~!fOl)F
:y~l?0b&8
return totalPage; nqYarHi
} V[*<^%
~c,+)69"T
privatestaticboolean hasPrePage(int currentPage){ ZB$,\|^6
return currentPage == 1 ? false : true; UWgPQ%}
} Y4Jaw2b
sVS),9\}
privatestaticboolean hasNextPage(int currentPage, a{I(Qh!}
(Kkqyrb
int totalPage){ #9(iu S+BU
return currentPage == totalPage || totalPage == ;|vn;s/
GQ9H>Ssz
0 ? false : true; )"bP]t^_
} B%co`0$
r+k~%5Ff~
qaBL
} DRu#vC
`g'9)Xf4KT
TwZmZE ?!
&K"qnng/y
lt C
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。 U)S!@2(4
>
8!9
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 a[BIY&/Q
QlnI &o
做法如下: $=!_ !tr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 OLJ|gunA#
H1ox>sC
的信息,和一个结果集List: UDgUbi^v|D
java代码: %c&<{D}r
|/RZGC4
u$V@akk
/*Created on 2005-6-13*/ mk`#\=GE
package com.adt.bo; UTxqqcqEny
y=e|W=<D&
import java.util.List; Tml>>O
hLSas#B>
import org.flyware.util.page.Page; G8CM
JN<u4\e{-&
/** X./7b{Pax
* @author Joa &Y8S! W@4
*/ d+6-ten
publicclass Result { qJJ~#W)
&Ht5!zuW,
private Page page; vy5SBiK
k
3oR:
private List content; ;LFs.Jc<
yex0rnQ|
/** BWG#W C
* The default constructor AI*1kxR
*/ ,a@jg&Mb]
public Result(){ T oK'Pd
super(); +Ft@S(IE
} cY%6+uJ1
IaYy5Rw
/** 2u^/yl
* The constructor using fields ;fKFmY41
* iriF'(1
* @param page /c52w"WW
* @param content {b]V
e/\
*/ l 1Ns~
public Result(Page page, List content){ !Im{-t
this.page = page; Ub*O*nre
this.content = content; CW;=q[+w
} hT$/ B|
CoQ<Ky}*
/** .hytn`+9
* @return Returns the content. F*/J`l
*/ =bl6:
publicList getContent(){ $n9Bp'<
return content; {-e|x&-
} 3q$"`w
]=T-Cv=t
/** A{KF<Omu
* @return Returns the page. i| OG#PsY-
*/ ~_hn{Ous
public Page getPage(){ (GDW9:
return page; H6%%n
X
} CUZ
;<Pn
\6c8Lqa
/** t8upS
u|
* @param content ~"#[<d
* The content to set. 1usLCG>w{
*/ 2:Q2w3Xe
public void setContent(List content){ tG(!d$^
this.content = content; )Uu! x6
} )_Wo6l)i
uO}UvMW
/** ^,N=GZRWW
* @param page dG*2-v^G
* The page to set. =?gDM[t^
*/ B|6_4ry0U
publicvoid setPage(Page page){ QwgP+ M+
this.page = page; "1%YtV5R{
} EnnE@BJ"
} u40<>A
f"g-Hbl5
w>Y!5RnO
&Uu8wFbIJ
:7jDgqn^|i
2. 编写业务逻辑接口,并实现它(UserManager, `oGL==
M*lCoJ
UserManagerImpl) zTvGku[3
java代码: w{5v*SHl}`
%XAF"J
Oa/# 2C~
/*Created on 2005-7-15*/ sAfNu~d
package com.adt.service; "YePd*W
SK G!DKQ
import net.sf.hibernate.HibernateException; b1ma(8{{{
&5o ln@YL
import org.flyware.util.page.Page; LyA}Nd]pyq
o!>h
Q#h
import com.adt.bo.Result; C p.qL
pLea 4
/** wwD?i.3
* @author Joa P\2UIAPa\b
*/ LyWgaf#/d
publicinterface UserManager { 2qxede
{m7>9{`
public Result listUser(Page page)throws ;@l5kdZx`
@eU5b63jM
HibernateException; 78-D/WY/X
6y+}=)J
} ]3bXJE
W$ag
|WV
QC^#ns&
*wD| eK7
xY94v
java代码: r\DA&b
/yNLFL"
}hyl)?*~
/*Created on 2005-7-15*/ 0s'H(qE,_
package com.adt.service.impl; vo JmNH
mx;1'!'fr
import java.util.List; GFppcL@a
Tq*K
=^
import net.sf.hibernate.HibernateException; o"-*,:Qe
pZaOd;t
import org.flyware.util.page.Page; =#|K-X0d=
import org.flyware.util.page.PageUtil; ~s4o1^6L
:#&Y
import com.adt.bo.Result; J2d3&6
import com.adt.dao.UserDAO; T.x"a$AU
import com.adt.exception.ObjectNotFoundException; HHcWyu
import com.adt.service.UserManager; .1#G*A|
Z %\*\6L)
/** -J\R}9 lIm
* @author Joa 4J${gcju
*/ 5
i;n:&Y
publicclass UserManagerImpl implements UserManager { L>.*^]
UG:S! w'
private UserDAO userDAO; na,i(m?l
1]% ]"JbV
/** (Ceq@eAlT
* @param userDAO The userDAO to set. +(l(|lQy$
*/ >4&s7][Q|
publicvoid setUserDAO(UserDAO userDAO){ NT&skrzW
this.userDAO = userDAO; >y{oC5S
} wseb]=U
k1HVvMD<
/* (non-Javadoc) dD.;P=AP
* @see com.adt.service.UserManager#listUser "Q<
E\lel4ai
(org.flyware.util.page.Page) lbUUf}
*/ nOj0"c
public Result listUser(Page page)throws # )]L3H<
;N;['xcx;
HibernateException, ObjectNotFoundException { y $6~&X
int totalRecords = userDAO.getUserCount(); }G53"
if(totalRecords == 0) B9i<="=p
throw new ObjectNotFoundException ,ctm;T1H+
|E5\_Z
("userNotExist"); !aQQq[
page = PageUtil.createPage(page, totalRecords); X8Y)5,`s
List users = userDAO.getUserByPage(page); ! uX0G4
returnnew Result(page, users); uk=f /nT
} \6WVs>z
g
r[M-U
} ;2%8tV$V
I5mtr
W&`{3L
#$;i 4a
lz>>{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Tw+V$:$$
%|\Af>o4d
询,接下来编写UserDAO的代码: |p\vH#6y+
3. UserDAO 和 UserDAOImpl: xq-TT2}<L
java代码: pf[m"t6G~
S&Szc0-|k
Bt[Wh@
/*Created on 2005-7-15*/ lJIcU
RI4
package com.adt.dao; _Z{EO|L
P'Diie
import java.util.List; 8k|&&3_[?
[,86||^
import org.flyware.util.page.Page; i4s_:%+
.bloaeu-
import net.sf.hibernate.HibernateException; w+W!dM
Cyu= c1D ;
/** fv+t%,++:
* @author Joa {#C)S&o)6
*/ (YC{BM}
publicinterface UserDAO extends BaseDAO { j Wjp0ii
=
iXHu
*g
publicList getUserByName(String name)throws wJMk%N~R:
}eq*dr1`
HibernateException; v{c,>]@
3[;fO_ R
publicint getUserCount()throws HibernateException; ScCA8JgY
G%FLt[
publicList getUserByPage(Page page)throws S\"#E:A
]21`x
HibernateException; x*7Q
"
.<>(bE
} s=[T,:Z
^sqTgrG
u}QcyG^
%ZbdWHO#
,:=g}i
java代码: *-\qO.4\
3$f+3/l
67D{^K"KT
/*Created on 2005-7-15*/ Ahf71YP
package com.adt.dao.impl; >_'0 s
I3,0vnE@
import java.util.List; LTlbrB
r<9G}9
import org.flyware.util.page.Page; 8_:j.(n
Jk>!I\
import net.sf.hibernate.HibernateException; )&vuT
q'7'
import net.sf.hibernate.Query; e<+$E%"7hS
Rx,5?*b$
import com.adt.dao.UserDAO; g)L<xN8
[M/0 Qx[,
/** ;m#_Rj6
* @author Joa ?mn&b G
*/ 57(5+Zme
public class UserDAOImpl extends BaseDAOHibernateImpl =lZtI6tZ
x +]ek
implements UserDAO { Y5z5LG4
|A, <m#C
/* (non-Javadoc) %n@ ^$&,&;
* @see com.adt.dao.UserDAO#getUserByName Y?#aUQc
x^~@`]TV^
(java.lang.String) 8.ej65r*
*/ J?"v;.K|hU
publicList getUserByName(String name)throws $w+()iI
k3CHv =U{
HibernateException { 6;Sz^W
String querySentence = "FROM user in class Jt(RF*i
7KJ%-&L^
com.adt.po.User WHERE user.name=:name"; ^@HWw@GA
Query query = getSession().createQuery 31&;3?3>
-^ R?O
(querySentence); m(KBg'kQ
query.setParameter("name", name); w\lc;4U
return query.list(); \N[2-;[3
} >J) 9&?
+%=lu14G
/* (non-Javadoc) MREB
* @see com.adt.dao.UserDAO#getUserCount() >UnLq:G
*/ ]O&\P n0q
publicint getUserCount()throws HibernateException { a^g}Z7D'T
int count = 0; Z9q1z~qSQ
String querySentence = "SELECT count(*) FROM ac%x\e$
LARMZoyi
user in class com.adt.po.User"; ^TEFKx}PX
Query query = getSession().createQuery szUJh9-
* -X`^R
(querySentence); LbUH`0:%t
count = ((Integer)query.iterate().next p`)Mk<`dYD
C8KV<k
()).intValue(); 'l $ViNq;
return count; '37 <+N
} 'OI(MuSn
UK5u"@T
/* (non-Javadoc) k2/t~|5
* @see com.adt.dao.UserDAO#getUserByPage h{ T{3
R5N~%Dg)3
(org.flyware.util.page.Page) ^Eif~v
*/ te;VGpv.
publicList getUserByPage(Page page)throws SZD7"m4
B|ctauJ
HibernateException { UetI4`
String querySentence = "FROM user in class )nlFyWXh.
{[~dI ~
com.adt.po.User"; #O N^6f2
Query query = getSession().createQuery WI1DL&*B@<
%$'Z"njO&
(querySentence); E<'V6T9bi
query.setFirstResult(page.getBeginIndex()) 8Om4G]*|,
.setMaxResults(page.getEveryPage()); sspGB>h8l
return query.list(); R>hL.+l.
} k>F>y|m
} 8[
} /^$n&gI
+zf`_1+)U
pfQ3Y$z
YBL.R;^v
w1LZ\nA<
至此,一个完整的分页程序完成。前台的只需要调用 g>QN9v})
w[g`)8Ib
userManager.listUser(page)即可得到一个Page对象和结果集对象 r0s(MyI
{hoe^07XK
的综合体,而传入的参数page对象则可以由前台传入,如果用 4+:'$Nw
Ctbc!<@o
webwork,甚至可以直接在配置文件中指定。 :A+}fBIN
3LZvlcLb
下面给出一个webwork调用示例: mhI
java代码: {7Hc00FM
7c83g2|%
d%:J-UtG"
/*Created on 2005-6-17*/ eq@-J+
package com.adt.action.user; `SQobH
T0N6k acl
import java.util.List; q<[o 4qY
QBd4ok:R
import org.apache.commons.logging.Log; YB.@zL0.(
import org.apache.commons.logging.LogFactory; ee{K5 G
import org.flyware.util.page.Page; 1[!7xA0 j
:OV6R,
import com.adt.bo.Result; [Pl''[
import com.adt.service.UserService; B &
]GGy
import com.opensymphony.xwork.Action; {E.A?yej9
B:ugEAo_
/** N%9?8X[5
* @author Joa y?Pw6;e.
*/ {a]u
publicclass ListUser implementsAction{ O7m-_#/\
EFv^uve
privatestaticfinal Log logger = LogFactory.getLog 8?ip,Q\
9\uBX.]x
(ListUser.class); [#%@,C
u/ri
{neP{
private UserService userService; I~4!8W-Y
?kS#g
private Page page; `A<2wd;
X6=o vm
privateList users; LTuT"}dT[
%CQv&d2
/* {s{+MbD
* (non-Javadoc) vy-q<6T}:p
* sl:1P^b
* @see com.opensymphony.xwork.Action#execute() :q~5Xw/
*/ VAA="yN
publicString execute()throwsException{ <fHN^O0TS
Result result = userService.listUser(page); `3*QKi$
page = result.getPage(); #e1iYFgS
users = result.getContent(); yq[.
WPve
return SUCCESS; lYmxd8
} :<HLw.4O
;]k\F
/** (gIFuOGi>
* @return Returns the page. ;rV+eb)I
*/ _{n4jdw%(
public Page getPage(){ -/Zy{2 <u
return page; 4'td6F
} &Zjs
s^m`qi(H
/** p0PK-e`@:
* @return Returns the users. 'F3@Xh
*/ sFHqLG{/
publicList getUsers(){ 'uF-}_
|
return users; n@6vCdk.
} ={51fr/C%
7=s0Pm
/** #CcEI
* @param page r;p@T8k
* The page to set. Gl"hn
*/ (M<l}pl)
publicvoid setPage(Page page){ gf}*}8D
this.page = page; ;@
G ^eQ
} lMcO2006L
@bChJl4
/** v +o6ZNX
* @param users dnV&U%fO
* The users to set. q=*bcDu
*/ pfw`<*e'
publicvoid setUsers(List users){ /1_O5'5+v
this.users = users; wPq9`9 #
} .hUlI3z9
pE%*r@p4&4
/** %:j`%F;R
* @param userService ""Oir!4
* The userService to set. 9W,%[
*/ j&
ykce
publicvoid setUserService(UserService userService){ f$vU$>+[
this.userService = userService; rjj_]1?K
} ;-_ZWk]
} 1/i1o nu}
gYbcBb%z
<~aKwSF[wW
/%gMzF
\UX9[5|
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, +3sbpl2}
Uy*d@vU9c
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 A8-a}0Gh
N1$PW~)Y
么只需要: 1K(mdL{m5
java代码: Zrj#4E1
0|C !n+OK
fs-LaV
0
<?xml version="1.0"?> tx)$4 v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork R0mkEM
2R,8q0qR:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- X|D-[|P
,*YmXR-"
1.0.dtd"> 5z2("[8L&
FM(EOsWk
<xwork> IZiS3
pjQyN|KS
<package name="user" extends="webwork- ><xmw=
qz2`%8}F)
interceptors"> n5;@}Rai
<4<y
<!-- The default interceptor stack name PKC0Dt;F.
y%x:~.
--> r;"D>IM\
<default-interceptor-ref n-{ d7haOa
x+ER 3wDD@
name="myDefaultWebStack"/> k_uI&,
mSvSdKKKlI
<action name="listUser" KN"u PW
\)6bLB!
class="com.adt.action.user.ListUser"> wLb:FB2
<param 4jGN:*kZ
t0r0{:
name="page.everyPage">10</param> _l1"X ^Aa
<result g-B{K "z
g^x=y
name="success">/user/user_list.jsp</result> ^2{ 6W6=
</action> G e5Yz.Qv
l)~U8
</package> 2`j{n\/
A{M7
</xwork> (y~%6o6
:U=3*f.{
)WW*X6[k
Lusd kc7
Q1ayd$W@<
<mj/P|P@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 lpS v
6VuyKt
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 v*FbvrY
vLBuE
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 OU}eTc(FeC
DVMdRfA
/xcXd+k]
6\jbSe
D$>&K&
我写的一个用于分页的类,用了泛型了,hoho *wY+yoj
iH@u3[w
java代码: nnvS.s`O
!]Qk?T~9-
IG{Me
package com.intokr.util; f6Lc"b3s1
#5kclu%L$
import java.util.List; Gqc6]{
>;R`Q9s7
/** .MRN)p
* 用于分页的类<br> 5f?GSHA}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Di27=_J
* 023uAaI^3r
* @version 0.01 9v;HE{>
* @author cheng L N.:>,
*/ 6xwjKh:9
public class Paginator<E> { mpCu,l+lo
privateint count = 0; // 总记录数 LI25VDZ|iP
privateint p = 1; // 页编号 &BNlMF
privateint num = 20; // 每页的记录数 sD2,!/'
privateList<E> results = null; // 结果 v\MQ?VC
:uB?h1|
/** b9"t%R9/Q
* 结果总数 UNF\k1[
*/ oU @!R
publicint getCount(){ 2+DK:T[
return count; <|.]$QSi
} EJMd[hMhe
r<Z .J/a
publicvoid setCount(int count){ CTKw2`5u
this.count = count; 'q_ Z
dw%
} 0Zp5y@V8
US3)+6
/** 9I2&Vx=DSt
* 本结果所在的页码,从1开始 0#Pa;(
* l4.ql1BX@y
* @return Returns the pageNo. =$^90Q,Z;
*/ }* }F_Y+
publicint getP(){ ::'Y07
return p; ~piE$"]&
} HeO&p@
RticGQy&5
/** 5h^BXX|Y*
* if(p<=0) p=1 1?^
P=^8
* H!hd0.
* @param p GnUD<P=I
*/ [KHlApL
publicvoid setP(int p){ s]6;*mI2
if(p <= 0) Y?7GFkIP$
p = 1; ~av#r=x
this.p = p; jO5R ~O`
} l0URJRK{*
4)k-gKS*
/** rNo/H<J%+j
* 每页记录数量 + 9|0\Q
*/ 00f'G2n
publicint getNum(){ .5!`wwVi
return num; ,7:-V<'Yv
} ]s^+/8d=
Vy[xu$y
/** (ER9.k2
* if(num<1) num=1 Wa.xm_4s2
*/ 8Dtpb7\o
publicvoid setNum(int num){ r-L& ee
if(num < 1) L@=$0p41;
num = 1; #Y3-P
this.num = num; b=\chCRJJ
} WQ8 "Jj?k6
WFV'^-4
/** *` wz
* 获得总页数 nw+^@|4
*/ C96*,.j~'
publicint getPageNum(){ 0A~UuH0.
return(count - 1) / num + 1; 3(|,:"9g
} $N}t)iA
~/)]`w
/** dI%ho<zm]
* 获得本页的开始编号,为 (p-1)*num+1 $ (xdF
*/ 1 n&%L8]
publicint getStart(){ Sw"h!\c`
return(p - 1) * num + 1; P(2OTfGGx
} ezY^T
RPf <-J:t
/** Oso**WUOZ&
* @return Returns the results. Qc?W;Q+
*/ p%sizn
publicList<E> getResults(){ %kop's&?C
return results; \xl$z*zI
} z,E`+a;
3 )#Nc|
public void setResults(List<E> results){ #}@8(>T
this.results = results; 8q{|nH
} tu$rVwgM
DUl+Jqn4B
public String toString(){ [wm0a4fg
StringBuilder buff = new StringBuilder ik/
X!YTu*
NziCN*6
(); 3imsIBr
buff.append("{"); X<C fy
buff.append("count:").append(count); s !2Iui
@
buff.append(",p:").append(p); /FC
HF#yK
buff.append(",nump:").append(num); S2Ez}*plp
buff.append(",results:").append ,.V<rDwN&
;n*|AL7(
(results); ~&RrlF h
buff.append("}"); +_pfBJ_$%
return buff.toString(); `o }+2Cb
} PMbZv%.,-
oOvQAW8`
} un~`|
u*I'c2m
Q8h0.(#-