Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 i<D}"h|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4XL*e+UfJ
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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 t+0&B"
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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 .%+`e
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分页支持类: pL$UI3VCP
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java代码: 7 q<UJIf
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package com.javaeye.common.util; @aR! -}
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import java.util.List; *AXu_^^
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publicclass PaginationSupport { SsjO1F
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publicfinalstaticint PAGESIZE = 30; cOUsbxYTD
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privateint pageSize = PAGESIZE; HMNjQ
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privateList items; 6G"AP~|0
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privateint totalCount; iV#JJ-OBq
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privateint[] indexes = newint[0];
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privateint startIndex = 0; =SLP}bP{:
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public PaginationSupport(List items, int /_rAy
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totalCount){ @f0~a
setPageSize(PAGESIZE); CAY^ `K!
setTotalCount(totalCount); c1wM "
setItems(items); aKaqi}IT
setStartIndex(0); ".| 9h
} >]"5K<-1
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public PaginationSupport(List items, int c=H(*#
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totalCount, int startIndex){ sS OI5W3A
setPageSize(PAGESIZE); iR4CY-
setTotalCount(totalCount); 9>psQ0IRvr
setItems(items); MoA2Cp;8X
setStartIndex(startIndex); GFvZdP`s4
} ,
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public PaginationSupport(List items, int 1rC8]M.N
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totalCount, int pageSize, int startIndex){ H;,cUb
setPageSize(pageSize); VS^%PM#:/
setTotalCount(totalCount); ,*0>CBJvv
setItems(items); xk86?2b{)
setStartIndex(startIndex); mKZ?H$E%%
} EA75
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publicList getItems(){ GZQ)TzR
return items; J),7ukLu^
} r4NI(\gU
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publicvoid setItems(List items){ %'`Dd
this.items = items; 'jcDfv(v<
} '2z o
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publicint getPageSize(){ r0QjCFSF=
return pageSize; F=B>0Q5
} ]*}*zXN/E
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publicvoid setPageSize(int pageSize){ jL8&
this.pageSize = pageSize; e }/c`7M
} ,{itnKJC
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publicint getTotalCount(){ j]J2,J
return totalCount;
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} 65ijzZL;
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publicvoid setTotalCount(int totalCount){ 0"u*K n
if(totalCount > 0){ qChS} Q
this.totalCount = totalCount; ^]wm Y
int count = totalCount / 4'+/R%jk"
-N5r[*>
pageSize; S=[K/Kf-
if(totalCount % pageSize > 0) QfU
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count++; GfQMdLy\Z
indexes = newint[count]; 5#d"]7
for(int i = 0; i < count; i++){ bm%2K@ /U
indexes = pageSize * VjYfnvE
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i; %S>lPt
} ,k{{ZP
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}else{ 2K,
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this.totalCount = 0; [$.oyjd
} H|F>BjXn5
} jY>KF'y
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publicint[] getIndexes(){ {>QrI4*A
return indexes; +ls *04
} HJBUN1n
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publicvoid setIndexes(int[] indexes){ ('
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this.indexes = indexes; S?hM
} R9S7p)B
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publicint getStartIndex(){ lDp5aT;DsM
return startIndex; ?xK9
} @Z@yI2#e
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publicvoid setStartIndex(int startIndex){ <6p{eGAQV
if(totalCount <= 0) QwOQS
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this.startIndex = 0; u9mMkzgSkP
elseif(startIndex >= totalCount) /CKkT.Le
this.startIndex = indexes xkUsZ*X8B
Ow//#:
[indexes.length - 1]; X@x:
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elseif(startIndex < 0) pl fz)x3
this.startIndex = 0; 4,H}'@Db}
else{ FjiLc=RXXz
this.startIndex = indexes ?Dd2k%o
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[startIndex / pageSize]; HW.S~eLw*
} qK|r+}g|&
} +tfmBZl^
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publicint getNextIndex(){ #:' P3)&
int nextIndex = getStartIndex() + ^_5$+
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pageSize; J>hl&J
if(nextIndex >= totalCount) seAkOIc
return getStartIndex(); sS5#Q
else + 6r@HK`,t
return nextIndex; (O&~*7D*
} P[XE5puC
tm+}@CM^.
publicint getPreviousIndex(){ N@Slc
0
int previousIndex = getStartIndex() - %l:%c
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pageSize; s%4)}w;z
if(previousIndex < 0) .fo.mC@a
return0; YqNhD6
else CoJaVLl
return previousIndex; \,p)
} /^/'9}7
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} *WMcE$w/D
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抽象业务类 r)X?H
java代码: %5F=!(w
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/** ^o?.Rph|i]
* Created on 2005-7-12 &
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*/ 8(Z*Vz uu
package com.javaeye.common.business; zac>tXU;
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import java.io.Serializable; Pq7YJ"Z?:
import java.util.List; LgUaX
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import org.hibernate.Criteria; |":^3
import org.hibernate.HibernateException; b.Y[:R_9&
import org.hibernate.Session; 'Iu$4xo`[
import org.hibernate.criterion.DetachedCriteria; Ypv"u0
import org.hibernate.criterion.Projections; /-BplU*"9
import zI7-xqZ
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org.springframework.orm.hibernate3.HibernateCallback; mi97$Cr2
import (x.K%QC)
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org.springframework.orm.hibernate3.support.HibernateDaoS _V8pDcY
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upport; 9^
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import com.javaeye.common.util.PaginationSupport; v`Sllv5bV
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public abstract class AbstractManager extends \n<N>j@3
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HibernateDaoSupport { [eWB
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privateboolean cacheQueries = false; ||L qx#e=
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privateString queryCacheRegion; $fnFi|-
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publicvoid setCacheQueries(boolean M6 0(yTm
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cacheQueries){ 7sLs+|<"
this.cacheQueries = cacheQueries; w,`x(!&
} jr!x)yd
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publicvoid setQueryCacheRegion(String evszfCH'J
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queryCacheRegion){ 7J>n;8{%?
this.queryCacheRegion = lZ_i~;u4@v
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queryCacheRegion; 9 .%{M#j
} oz[E>%
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publicvoid save(finalObject entity){ $,h*xb.
getHibernateTemplate().save(entity); VnIJ$5Y
} q~l&EH0
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publicvoid persist(finalObject entity){ i 3?zYaT
getHibernateTemplate().save(entity); ;'vY^I8-L
} 1Z`<HW"
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publicvoid update(finalObject entity){ \".3x
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getHibernateTemplate().update(entity); a_x|PbD
} RqcX_x(p
7 v`Y*D
publicvoid delete(finalObject entity){ :5CwRg
getHibernateTemplate().delete(entity); >#0yd7BST
} /"/$1F%{
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publicObject load(finalClass entity, ,VHvQU
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finalSerializable id){ I{1w8m4O6
return getHibernateTemplate().load g~Q#U;]
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(entity, id); 2V F|T'h
} y f+/Kj<
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publicObject get(finalClass entity, 9"<)DS
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finalSerializable id){ U'lrdc"Q
return getHibernateTemplate().get wetkmd
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(entity, id); l"ih+%S
} tnKzg21%
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publicList findAll(finalClass entity){ 5IMh$!/uc
return getHibernateTemplate().find("from YHeB<v
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" + entity.getName()); S!g&&RDx
} <y`yKXzBUV
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publicList findByNamedQuery(finalString n}?kQOg0/
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namedQuery){ -{P)\5.L
return getHibernateTemplate TWxMexiW
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().findByNamedQuery(namedQuery); !})+WSs'"s
} GH:Au
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publicList findByNamedQuery(finalString query, l}<s~ip
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finalObject parameter){ !5=3Y4bg1
return getHibernateTemplate i4Fw+Z
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().findByNamedQuery(query, parameter); rU'&o) a^
} 7 H<_
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publicList findByNamedQuery(finalString query, (cA=~Bw[=
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finalObject[] parameters){ -G*u2i_*
return getHibernateTemplate v_G4:tY
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().findByNamedQuery(query, parameters); I#9K/[
} =#>P!
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publicList find(finalString query){ l kl#AH
return getHibernateTemplate().find ExnszFX*
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(query); Wje7fv
} l sUQ7%f
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publicList find(finalString query, finalObject {O!fV<Vx 9
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parameter){ oXz:zoNQ
return getHibernateTemplate().find =zbrXtp,
7f
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(query, parameter); U(i2j)|^I3
} 9N
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public PaginationSupport findPageByCriteria g[Yok`e[
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(final DetachedCriteria detachedCriteria){ vguqk!eo4
return findPageByCriteria |r3eq4$Am
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r5F#q
} }RM?gE
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public PaginationSupport findPageByCriteria VoP(!.Ua>7
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(final DetachedCriteria detachedCriteria, finalint ,cj34W`FWq
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startIndex){ LfK <%(:
return findPageByCriteria 3 #jPQ[+
"h)+fAT|,
(detachedCriteria, PaginationSupport.PAGESIZE, tb_}w@:kU
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startIndex); %=NqxF>>
} &Cdd
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public PaginationSupport findPageByCriteria mk[=3!J
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(final DetachedCriteria detachedCriteria, finalint F v(zql
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pageSize, {zg}KiNDZd
finalint startIndex){ ;,9|;)U?u
return(PaginationSupport) iaPY>EP1
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getHibernateTemplate().execute(new HibernateCallback(){ EV~_-YC
publicObject doInHibernate WlG/7$
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(Session session)throws HibernateException { n1!u
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Criteria criteria = znu?x|mV
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detachedCriteria.getExecutableCriteria(session); jIuE1ve
int totalCount = k deJB-
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((Integer) criteria.setProjection(Projections.rowCount 7(wY4T
EP{y?+E2
()).uniqueResult()).intValue(); 0R*!o\y
criteria.setProjection (\SxG\`
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(null); vY.p~3q :)
List items = ~/gqXT">
;.m"y-
criteria.setFirstResult(startIndex).setMaxResults JJ[J'xl@
q}+9$v
(pageSize).list(); VE{t]>*-u
PaginationSupport ps = \t )Zk2
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new PaginationSupport(items, totalCount, pageSize, ]Ub?Wo7F?
w'cZ\<N[
startIndex); |%TH|?kB
return ps; 2uqdx'^"
} H%sbf&
gi
}, true); &o)j@5Y?
} +/AW6
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public List findAllByCriteria(final 6``!DMDt/P
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DetachedCriteria detachedCriteria){ Soq
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return(List) getHibernateTemplate oSTGs@EK
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().execute(new HibernateCallback(){ E[e ''
publicObject doInHibernate 8Gs{Zfp!D
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(Session session)throws HibernateException { _`ot||J
Criteria criteria = ~
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detachedCriteria.getExecutableCriteria(session); @u$4{sjgf\
return criteria.list(); /|hKZTZJdN
} N{oD1%
}, true); $FCLo8/=
} T2^@x9
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public int getCountByCriteria(final ar>S_VW*
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DetachedCriteria detachedCriteria){ 8'/vW ~f
Integer count = (Integer) K]Ed-Tz8QZ
* 496"kU
getHibernateTemplate().execute(new HibernateCallback(){ $40tAes9
publicObject doInHibernate J
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(Session session)throws HibernateException { CCQ<.iCU
Criteria criteria = I?5#Q0,b
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detachedCriteria.getExecutableCriteria(session); >CNH=
return 42X[Huy]
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criteria.setProjection(Projections.rowCount QnVYZUgJeV
q=g;TAXZl
()).uniqueResult(); /R@eOl}D
} XG_lyx%:E
}, true); 6uR:/PTG
return count.intValue(); c00a;=ji
} w_4`Wsn
} IQY\L@"
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用户在web层构造查询条件detachedCriteria,和可选的 If2f7{b
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 M>8#is(pV
#t
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PaginationSupport的实例ps。 *|ubH?71%Y
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ps.getItems()得到已分页好的结果集 8T7[/"hi\
ps.getIndexes()得到分页索引的数组 I@7^H48\
ps.getTotalCount()得到总结果数 jh2D9h
ps.getStartIndex()当前分页索引 ')+'m1N
ps.getNextIndex()下一页索引 B]0`b1t
ps.getPreviousIndex()上一页索引 lP\7=9rh^x
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7WKb|
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 .$L'Jt2X
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一下代码重构了。 D3|y|Dr
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我把原本我的做法也提供出来供大家讨论吧: {!Jw+LPv$$
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首先,为了实现分页查询,我封装了一个Page类: vRYfB{~
java代码: M7BJ$fA0E
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/*Created on 2005-4-14*/ 9}:%CpD^~I
package org.flyware.util.page; ggXg4~WL
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/** |ILj}4ZA7
* @author Joa \Om.pOz
* yiWBIJ2Wu9
*/ q0SYV
publicclass Page { $0+AR)
{D 9m//x
/** imply if the page has previous page */ G;>b}\Ng
privateboolean hasPrePage; 7GB>m}7
&r;-=ASYzV
/** imply if the page has next page */ TW7jp
privateboolean hasNextPage; _>S."cm}!k
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/** the number of every page */ 4D0=3Vy
privateint everyPage; 48Vmz
Q+$+{g-8
/** the total page number */ L$=6R3GI
privateint totalPage; #kR8v[Z
8rx?mX,}
/** the number of current page */ ,-rOfk\u
privateint currentPage; m+?$cyA>v
1 }%vZE2
/** the begin index of the records by the current jhr:QS/9
>\+c@o[
query */ &O/;YGEAB
privateint beginIndex; "
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/** The default constructor */ %scSp&X
public Page(){ :D\M.A
xKi:
2
} S|CN)8Jsi
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/** construct the page by everyPage z'z_6]5
* @param everyPage BGh1hyJ8d
* */ \vjIw{
public Page(int everyPage){ iO4Yfj#?
this.everyPage = everyPage; h8iic
} \fj*.[,
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/** The whole constructor */ _a|-_p
public Page(boolean hasPrePage, boolean hasNextPage, @eU;oRVc{
=]X_wA;%
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int everyPage, int totalPage, zy^t95/m
int currentPage, int beginIndex){ ue"?n2
this.hasPrePage = hasPrePage; 6q-X$
this.hasNextPage = hasNextPage; o
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this.everyPage = everyPage; 4! ]28[2B6
this.totalPage = totalPage; 5?9K%x'b
this.currentPage = currentPage; (,*e\o
this.beginIndex = beginIndex; 7:awUoV8f
} 2K[Y|.u8>q
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/** Q"itV&d,
* @return &Azfpv
* Returns the beginIndex. + :4
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*/ U.g7' `Z<
publicint getBeginIndex(){ _Vul9=
return beginIndex; C^oj/}^
} v50w}w'
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/** R~TzZ(Ah]
* @param beginIndex )(V|d$n
* The beginIndex to set. uJhB>/Og
*/ " iAwD8-
publicvoid setBeginIndex(int beginIndex){ @#m@ .
this.beginIndex = beginIndex; )nE=H,U?y
} \JjZ _R
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/** O1]L4V1iH
* @return 1X.E:
* Returns the currentPage. QfPsF@+-`7
*/ k;BXt:jDq
publicint getCurrentPage(){ Z'=:Bo{
return currentPage; PggjuPPh
} )zn`qaHK@e
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/** O\0]o!
* @param currentPage CNU,\>J@$
* The currentPage to set. mcO/V-\5'
*/ drRi<7
i
publicvoid setCurrentPage(int currentPage){ K X0{dizZ
this.currentPage = currentPage; nD#QC=}
} W5a7HkM
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/** &}}UdJ`
* @return fib#)KE
* Returns the everyPage. % \N52
*/ 8);G'7O
publicint getEveryPage(){ l5;
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return everyPage; J[ 0o6
} .: dy d
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/** hJ|zX
* @param everyPage gu:8+/W8L
* The everyPage to set. -]hk2Q0
*/ my1FW,3
publicvoid setEveryPage(int everyPage){ U0X,g(2'
this.everyPage = everyPage; k9Pwf"m|](
} gs/ i%O
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/** ~F; ~
* @return ZhvZe/
* Returns the hasNextPage. bEvlk\iql
*/ ) oypl+y
publicboolean getHasNextPage(){ kn5X:@{
return hasNextPage; $f>h_8cla
} 41^ =z[k
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/** STln_'DF'
* @param hasNextPage n VNz5B
* The hasNextPage to set. ."X}A
t
*/ xOY
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publicvoid setHasNextPage(boolean hasNextPage){ t,P_&0X
this.hasNextPage = hasNextPage; mc
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} p<[gzmU9\b
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/** \mo NpKf
* @return IJ[r!&PY
* Returns the hasPrePage. (D5sJ$&E@\
*/ cVb&Jzd
publicboolean getHasPrePage(){ b aO^Z
return hasPrePage; UA0j#
} O-uno{Fd*
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/** ^osXM`
* @param hasPrePage $:l>g)c
* The hasPrePage to set. A.YXK%A%
*/ =%=lq0GF0
publicvoid setHasPrePage(boolean hasPrePage){ &hnI0m=X
this.hasPrePage = hasPrePage; @y ImR+^.7
} S&JsDPzSd
! )x2
/** WgTD
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* @return Returns the totalPage. od=x?uBVd
* dilom#2l
*/ <@448,9&
publicint getTotalPage(){ _/c1b>kcso
return totalPage; ovXU +8
} *r90IS}A$2
-ZVCb@%
/** tg~@(IT}j
* @param totalPage nhdOo
* The totalPage to set. >))f;$D=
*/ /XVjcD66c
publicvoid setTotalPage(int totalPage){ R`HC
EX)
this.totalPage = totalPage; L^E#"f
} QKB*N)%6
cfZ$V^xM
} tEam6xNf,
ATG;*nIP
E3vYVuw
{9
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kfW"vI+d
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Vu=e|A#
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个PageUtil,负责对Page对象进行构造: !E@4^A80\W
java代码: UURYK~$K:
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/*Created on 2005-4-14*/ ,'Sj:l
package org.flyware.util.page; '_~qAx@F#c
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; xQ0.2[*5
Y
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/** rgw@
* @author Joa EGMIw?%Y`-
* jY1^I26E
*/ I6e[K(7NY
publicclass PageUtil { b2r]>*Vc
|L<p90
privatestaticfinal Log logger = LogFactory.getLog Da3Z>/S
VFI\2n`
(PageUtil.class); h1
npaD!
nRHxbE}::
/** VV+gPC
* Use the origin page to create a new page +bDBc?HZ{$
* @param page 8\VP)<<
* @param totalRecords {9Ug9e{
~
* @return AW<"3 !@
*/ ZBuh(be
publicstatic Page createPage(Page page, int :9~LYJ
?
P _x(`H
totalRecords){ 2
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return createPage(page.getEveryPage(), =nff;Xu
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page.getCurrentPage(), totalRecords); E (.~[-K4
} `k.0d`3(
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/** ,_M
* the basic page utils not including exception roM!%hb
93VbB[w~7F
handler `8lS)R!
* @param everyPage w.o>G2u
* @param currentPage 8= "01
* @param totalRecords `e[>S
* @return page <Toy8-kj
*/ OB4nE}NO
publicstatic Page createPage(int everyPage, int /e;E+
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currentPage, int totalRecords){ A4{p(MS5
everyPage = getEveryPage(everyPage); 91\Sb:>
currentPage = getCurrentPage(currentPage); oJ.5! Kg
int beginIndex = getBeginIndex(everyPage, +mRc8 G
Zg&o][T
currentPage); 6Z#$(oC
int totalPage = getTotalPage(everyPage, G0Y]-*1
f\vMdY
totalRecords); V\nj7Gr:sF
boolean hasNextPage = hasNextPage(currentPage, 8pXqgIbmb
>&YUV.mLY
totalPage); tjg?zlj
boolean hasPrePage = hasPrePage(currentPage); XGb*LY+Db6
Ws/\lD
returnnew Page(hasPrePage, hasNextPage, {!&^VXZIT
everyPage, totalPage, QAzwNXE+
currentPage, POI|#[-V
q:MSV{k
beginIndex); k+@,m\tE
} -q30tO.
3}2;*:p4Y
privatestaticint getEveryPage(int everyPage){ lBzfBmEB
return everyPage == 0 ? 10 : everyPage; 'Px}#f0IR
} L\zyBfK}
[NoO A
privatestaticint getCurrentPage(int currentPage){ (Xl+Zi>\{
return currentPage == 0 ? 1 : currentPage; (B0QBDj!
} 9]%2Yb8SC
1]a\uq}
privatestaticint getBeginIndex(int everyPage, int kB9@
&t+
43,baeG
currentPage){ ]^53Qbrv
return(currentPage - 1) * everyPage; tGJJ|mle>
} L/?jtF:o
/ ?'FSWDU
privatestaticint getTotalPage(int everyPage, int BG8`B'i
&3$FkU^F6
totalRecords){ a0&L,7mu<'
int totalPage = 0; * hmoi
*]:J@KGf
if(totalRecords % everyPage == 0) ;(@' +"
totalPage = totalRecords / everyPage; ]E$bK
else >rXD Lj-e
totalPage = totalRecords / everyPage + 1 ; 7.kgQ"?&
H X{K5 +
return totalPage; k=4C"
} l5nm.i<M
vA2>&YDFX
privatestaticboolean hasPrePage(int currentPage){ q 7-ZPX
return currentPage == 1 ? false : true; T3NH8nH9"z
} w<u@L
>dJ[1s]
privatestaticboolean hasNextPage(int currentPage, 1i&|}"
to;^'#B
int totalPage){ <+UJgB
A-
return currentPage == totalPage || totalPage == H8kB.D[7Q
O%f{\Fr
0 ? false : true; vNHvuwK
} 3el/,v|qj
I;9C":'#
sIMN""@Y^
} P@5}}vwS
hkOFPt&
y3':x[d
_jb&=f8
A=sz8?K+`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 4Uhh]/
h_Ssm{C\
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 2UG>(R:
mNlbiB
做法如下: TBZhL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @KRia{
`CRF E5
的信息,和一个结果集List: 0oe2X1.%
java代码: j;I(w [@P
WfHa
nlZJ}xZ
/*Created on 2005-6-13*/ P%;lHC #i
package com.adt.bo; @~}~;}0x
L}7 TM:%
import java.util.List; U|<>xe*|%
'Ck:=V%}g
import org.flyware.util.page.Page; LLL;SNY
Zrzv';
/** X%5 `B2Wu
* @author Joa T$sm}=
*/ ehLn+tg
publicclass Result { < lUpvr
b2H-D!YO^
private Page page; 0p+36g
kjDmwa+91T
private List content; Nza@6nI"
>2v<;.
/** X|yVRQ?F`
* The default constructor 6n|][! f
*/ _S,UpR~2W
public Result(){ [_`@V4
super(); k;K-6<^h
} 0+k..l
+R7pdi
/** A-, hm=?
* The constructor using fields =b8u8*ua
* B.!&z-)#
* @param page T
oT('
* @param content jZH4]^De
*/ uqD|j:~ =k
public Result(Page page, List content){ s@E)=;!
this.page = page; Yr\quinLL
this.content = content; #.vp\W
} 2D a0*xn{
4,f`C0>"
/** x=-(p}0o;<
* @return Returns the content. DXFDs=u
*/ r?w>x`
publicList getContent(){ do9~#F
return content; "Th;YJu
} m.<or?l'y>
j{johV+`8
/** A]1dR\p
* @return Returns the page. BSy{"K*M
*/ O0s,)8+z5D
public Page getPage(){ W*?qOq
{
return page; h(^c5#.
} Z;[xaP\S
,L
MN@G
/** hUX8j9N>
* @param content qL
<@PC.5
* The content to set. i3pOGa<
*/ G`/4n@
public void setContent(List content){ *^Ro I
this.content = content; ?a*w6,y.
} DL d~
=nO:R, U
/** ]+b?J0|P<
* @param page WJI}~/z;C
* The page to set. .Yvy37n((
*/ lANi$
:aE
publicvoid setPage(Page page){ !/ dH"h
this.page = page; pMY7{z
} [XH,~JZJj
} CpK:u!
Dn
I!}V+gu=
(N/-blto
x iz+R9p
pju*i6z
2. 编写业务逻辑接口,并实现它(UserManager, 6pt|Crvu
R+!oPWfb
UserManagerImpl) Y;iI=U
java代码: ]
_W'-B
B.KK@
4>2\{0r
/*Created on 2005-7-15*/ O9m sPb:
package com.adt.service; <WnIJum
#DARZh U)
import net.sf.hibernate.HibernateException; m%UF{I,
'+ mI
import org.flyware.util.page.Page; 66sgs16k
feH&Ug4?G
import com.adt.bo.Result; nE?:nJ|%E
WncHgz
/** /D yig
* @author Joa \Ui8gDJ8y5
*/ y~Yv^'Epf
publicinterface UserManager { ,7 m33Pv*
_\8E/4zh
public Result listUser(Page page)throws X"mPRnE330
W7(5z
HibernateException; X-Ev>3H
:fnJp9c
} %Pl |3 i
}D`ZWTjDay
,9"du
Z15=vsV
X$G:3uoN
java代码: r\}?HS06
\){_\{&
Pa#Jwo
/*Created on 2005-7-15*/
Lsai8 B
package com.adt.service.impl; .gNziDO
mM2I
import java.util.List; .:4*HB
I+ 3qu=
import net.sf.hibernate.HibernateException; q2OF-.rE
}}u`*&,g
import org.flyware.util.page.Page; &;WK=#
import org.flyware.util.page.PageUtil; S,udpQ7
U>00B|<GJ
import com.adt.bo.Result; kGC*\?<LmR
import com.adt.dao.UserDAO; ^CM@VmPp
import com.adt.exception.ObjectNotFoundException; "=KFag
import com.adt.service.UserManager; 9YB?wh'S[
t-n'I/^5
/** Nf2lw]-G4
* @author Joa 7xY&7 x(v
*/ dd;rnev+
publicclass UserManagerImpl implements UserManager { Vq/hk
1|s`z
private UserDAO userDAO; 0v6Z4Ahpo
;8
*"c
/** ;CoD5F!
* @param userDAO The userDAO to set. T00sYoK
*/ ~IPATG
publicvoid setUserDAO(UserDAO userDAO){ {X<_Y<
this.userDAO = userDAO; ;Jb%2?+=!
} PMX'vA`
m(dW["8D
/* (non-Javadoc) b"`Q&V.
* @see com.adt.service.UserManager#listUser ke KsLrd
<0m^b#hdG
(org.flyware.util.page.Page) >WJQxL4
*/ 6' \M:'<0e
public Result listUser(Page page)throws wuxOFlrg
r+6 DlT
a
HibernateException, ObjectNotFoundException { U#sv.r/L}3
int totalRecords = userDAO.getUserCount(); 69Z`mR
if(totalRecords == 0) 7l09
throw new ObjectNotFoundException ^^24a_+2
{zc*yV\
("userNotExist"); 0F6@aQ\y3
page = PageUtil.createPage(page, totalRecords); |Q@( <'8=
List users = userDAO.getUserByPage(page); ftRdK>a
D
returnnew Result(page, users); x_/l,4_
} BeD>y@ it
Fi 7~JZZ
} R<hsG%BS(D
X+ybgB4(
1W-kZ(e
Lpnw(r9Y
0B2f[A
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "4T36b
s<:);-tL
询,接下来编写UserDAO的代码: &oJ[ *pQ
3. UserDAO 和 UserDAOImpl: a@9W'/?igk
java代码: |mdf u=
0R0_UvsXU
q$s)(D
/*Created on 2005-7-15*/ \f VX<L
package com.adt.dao; ^JY:$)4["
/xr75|-8
import java.util.List; `#r/L@QI
KV'3\`v@LY
import org.flyware.util.page.Page; .m%5Esx
hYA1N&yz@
import net.sf.hibernate.HibernateException; c=a;<,Rzb
\l# H#~
/** %kH,Rl\g
* @author Joa X'%BS
*/ -]YsiE?r
publicinterface UserDAO extends BaseDAO { Nr"GxezU+A
0C"2?etMx
publicList getUserByName(String name)throws 7|[Dr@.S
. S;o#Zw*R
HibernateException; t: ,lz8Y~
ADP3Nic
publicint getUserCount()throws HibernateException; <]#_&Na
W'E3_dj+
publicList getUserByPage(Page page)throws VG$%Vs
Tc/<b2\g
HibernateException; CPY|rV
:9q|<[Y^
} AT2D+Hi=E
xa
!/.
1-<?EOYaE
!wKNYe
jd"YaZOQ
java代码: >>;He7
>m=XqtP
v0;dk(
/*Created on 2005-7-15*/ An,TunX
package com.adt.dao.impl; D.a\O9q"&{
5l(@p7_+
import java.util.List; 7E?60^Tve
goD#2lg
import org.flyware.util.page.Page; o?3C -A|
:Fh _Ya0
import net.sf.hibernate.HibernateException; DIhV;[\
import net.sf.hibernate.Query; QYAt)Ik9q
)IIWXN2A
import com.adt.dao.UserDAO; gy#G; 9p
_?bF;R
/** EU Oa8Z
* @author Joa KEq48+j
*/ D6\k}4n-
public class UserDAOImpl extends BaseDAOHibernateImpl )sK_k
U{\
SpEu>9g&
implements UserDAO { <BBSC
tqKX\N=5^
/* (non-Javadoc) iRv\:.aQ.
* @see com.adt.dao.UserDAO#getUserByName 4s <ZKU
0f5)]
(java.lang.String) em ]0^otM
*/ 6}\J-A/
publicList getUserByName(String name)throws /$FpceB!W
"Gq%^^*
HibernateException { :&RpB^]
String querySentence = "FROM user in class I Vw'YtZ
<){J|O
com.adt.po.User WHERE user.name=:name"; 92*"3)
Query query = getSession().createQuery "9y0]~
"M %WV>
(querySentence); !;Ctz'wz
query.setParameter("name", name); F)S?>P&
return query.list(); T\7t#Z
k
} K2tOt7M!
N'21I$ D
/* (non-Javadoc) {Z~ze` N/
* @see com.adt.dao.UserDAO#getUserCount() Eqx |k-<a
*/ j<w5xY
publicint getUserCount()throws HibernateException { _sCzee&uQ
int count = 0; mP_c-qD
|
String querySentence = "SELECT count(*) FROM iTCY $)J
P Qi=
user in class com.adt.po.User"; o'YK\L!p
Query query = getSession().createQuery quq !Jswn
1t#|MH
?U_
(querySentence); <sjz_::V8R
count = ((Integer)query.iterate().next =Zaw>p*H
0!1cHB/c
()).intValue(); ;PMy9H
return count; N_VWA.JHt
} @4]dv> Z
#/hXcF
/* (non-Javadoc) cA!o
xti
* @see com.adt.dao.UserDAO#getUserByPage
'^,|8A2
uC 2{
Mmy
(org.flyware.util.page.Page) 0qN+W&H
*/ o&?:pE
publicList getUserByPage(Page page)throws l<s6Uu"
<VT|R~
HibernateException { ]Lm?3$u$
String querySentence = "FROM user in class (
D@U%
Qf}}/k|)k
com.adt.po.User"; TM,Fab &
Query query = getSession().createQuery QnIF{TS=
e:|Bn>*
(querySentence); GVM)-Dp]
query.setFirstResult(page.getBeginIndex()) zf[KZ\6H
.setMaxResults(page.getEveryPage()); n55s7wzM
return query.list(); fZxEE~Q1
} 4ZT0~37(
*k;%H'2g{}
} QU)AgF[
7x(z
-Vjrh/@
/f! ze|
L:UPS&)
至此,一个完整的分页程序完成。前台的只需要调用
?!n0N\|i]
NH8\}nAK
userManager.listUser(page)即可得到一个Page对象和结果集对象 <e-hR$
Sfffm$H
的综合体,而传入的参数page对象则可以由前台传入,如果用 [nB4s+NX
@t3I}mc
webwork,甚至可以直接在配置文件中指定。 ;2,Q:&`
)"Dl,Fig:/
下面给出一个webwork调用示例: nSbcq>3
java代码: _Xfn
JZoH -
$HFimU,V=0
/*Created on 2005-6-17*/ 4@Xd(F_d
package com.adt.action.user; j\uPOn8k
g6;a2
import java.util.List; 1&utf0TX6q
.J2tm2]"EZ
import org.apache.commons.logging.Log; ~s)
`y2Y
import org.apache.commons.logging.LogFactory; <USr$
import org.flyware.util.page.Page; z_t%n<OvK
Q;2n
import com.adt.bo.Result; *o#P)H
import com.adt.service.UserService; [^\HP]*Q{
import com.opensymphony.xwork.Action; |OO2>(Fj
-AM(-
/** VNxhv!w
* @author Joa h`V#)Q
*/ i0{sE
publicclass ListUser implementsAction{ [?VkwFD0
7DWHADr
privatestaticfinal Log logger = LogFactory.getLog M}N[> ,2'
::p(ViYG
(ListUser.class); bA(-7l?
Q=F4ZrNqD
private UserService userService; ^wb$wtL('
Q>l5:2lq
private Page page; <PpW.1w
&z;1Z
privateList users; ,<]~/5-f
=~'{2gsB
/* A=\:b^\
* (non-Javadoc) rLI);!^-
* }+GIrEDId
* @see com.opensymphony.xwork.Action#execute() n_P2l<F~/x
*/ I_iXu;UX
publicString execute()throwsException{ ECLQqjB
Result result = userService.listUser(page); &&`-A6`p
page = result.getPage(); unAu8k^
users = result.getContent(); /fC8jdp&
return SUCCESS; i-`J+8|d
} v|; }}ol
g I@I.=y
/** ?9:~d#p
* @return Returns the page. 2D'$
*/ {7LNQGiJ
public Page getPage(){ :Wd@Qy?;
return page; rFG_CC2
} ~cb7]^#u1l
L31#v$;4
/** ;;7:l,vy
* @return Returns the users. d\j[O9W>
*/ m 9.BU2.
publicList getUsers(){ L IRdWGQ4
return users; jLF,R7t
} mD go@f
gEkH5|*Y
/** E}8wnrxf
* @param page >\ x!a:}
* The page to set. j5bp)U
*/ "|<U`3y6
publicvoid setPage(Page page){ {# Vp`ji
this.page = page; V8"m_
} 5PPaR|c3
e&ci\x%
/** ^#)]ICV
* @param users I|vfxf
* The users to set. N7mYE
*/ hmr 2(f%U
publicvoid setUsers(List users){ d3tr9B
this.users = users; @$!rgLyL[
} lkaWwjv_D
UA(&_-C\
/** F`RPXY`ux
* @param userService LV`tnt's
* The userService to set. cOvdC4
*/ s1%th"e
[
publicvoid setUserService(UserService userService){ +vO;J
this.userService = userService; /DoSU>%hK
} t lpTq\;
} JbXd9AMh2
*8I &|)x
!]t5(g_
`xF^9;5mi
=.ReM_.
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, Ktn:6=,
#-8%g{
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 '0
J*9
"-:-!1;Ji
么只需要: fOt?2Bh
java代码: Ln"D .gpq
/xw}]Fa5
ZXC_kmBN/
<?xml version="1.0"?> k8E{pc6;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 4{CeV7
^~JF7u
1.0//EN" "http://www.opensymphony.com/xwork/xwork- uXo?
x<\5Jrqt
1.0.dtd"> KK,
t !a
_o'a|=Osx>
<xwork> |wGmu&fY
^:Fj+d
<package name="user" extends="webwork- F-%Hw
f:KZP;/[c
interceptors"> \t?rHB3"
QyD(@MFxb
<!-- The default interceptor stack name (qDPGd*1
k]9+/$
--> kV@?Oj.&I,
<default-interceptor-ref HJjx!7h
KuZZKh
name="myDefaultWebStack"/> #R*7y%cO
g<g$c<sm
<action name="listUser" =+w!fy
-
`{T ?
class="com.adt.action.user.ListUser"> }j;G`mV2
<param {iYrC m[_
ErxvGB(2
name="page.everyPage">10</param> EHk$,bM
<result <ZjT4><
y_LFkZ
name="success">/user/user_list.jsp</result> 0^K2"De
</action> -1} &\=8M
+,T z +!
</package> \HQw$E/p
QzVo U |
</xwork> l-$5CO
U<I]_]
U88gJ[$
6 l7iX]
]\ t20R{z
g9@H4y6fe=
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 BKKW3PT
<kKuis6h
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。 pMd!Jl#(N
&X#6jTh+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 (Rh$0^)A
2hsRYh
y
'Ah*h
A$70!5*
jx14/E+^
我写的一个用于分页的类,用了泛型了,hoho </!GU*
E?S
java代码: qyzH*#d=Cf
mwO9`AU;
yb!/DaCd
package com.intokr.util; sq{=TB{
13fyg7^JP
import java.util.List; `t3w|%La}
LjCUkbzQF
/** .S[M:<<*
* 用于分页的类<br> 8(g}/%1mt3
* 可以用于传递查询的结果也可以用于传送查询的参数<br> p# JPLCs
*
_6-N+FI
* @version 0.01 c!N#nt_<
* @author cheng 7n]ukqZ
*/ TjicltQi4
public class Paginator<E> { X}g"_wN,g>
privateint count = 0; // 总记录数 W:hTRq
privateint p = 1; // 页编号 E8L\3V4
privateint num = 20; // 每页的记录数 lUd4`r"
privateList<E> results = null; // 结果 Qt>Bvu Q
$kc cM&B
/** ;$3epP
* 结果总数 T_[
*/ `6<Qb=
publicint getCount(){ <Vl`EfA(
return count; >dXB)yl
} T%4yPmY
UJ><B"
publicvoid setCount(int count){ b8**M'k
this.count = count; %E[ $np>
} 3hcWR'|
SB,#y>Zv?
/** f`YHZ
O
* 本结果所在的页码,从1开始 49=
K]X
* kn+@)3W:*
* @return Returns the pageNo. +2>, -V
*/ Cz6bD$5
publicint getP(){ .>1vN+
return p; s9SUj^
} E:Ul_m8
V/tl-;W
/** <Ok7-:OxA
* if(p<=0) p=1 C!Jy;Z=+u
* \+"Jg/)ij
* @param p 5xQ5)B4k
*/ WO$8j2!~#
publicvoid setP(int p){ Ld
0j!II(
if(p <= 0) `4wy
*!]
p = 1; 0-p
%.}GE
this.p = p; 5t|$Yt[
} LI>Bl
h{ZK;(u$
/** r,q.RWuII
* 每页记录数量 ! LCy:>i!d
*/ ,(f({l[J}
publicint getNum(){ 'p)DJUwt
return num; WW-}c;cnK
} JFq<sY!
>7z(?nQYT^
/** lo-VfKvy
* if(num<1) num=1 }(oWXwFb&W
*/ xeKm} MN]S
publicvoid setNum(int num){ \H
5t-w=
if(num < 1) 8 %p+:6kP5
num = 1; pZ]&M@Ijp
this.num = num; <)
-]'@*c
} xl Q]"sm1
t ?05
/** !Ej?9LHo
* 获得总页数 [LrO"9q(
*/ #)s
+I2
publicint getPageNum(){ 2fXwJG'
return(count - 1) / num + 1; 8!
/ue.T
} {\X$vaF
TN<"X :x9
/** ^!$=(jh.
* 获得本页的开始编号,为 (p-1)*num+1 n`!6EaD
*/ yv: Op\;R
publicint getStart(){ &3SmTg
%
return(p - 1) * num + 1; ]2{]TJ@B
} ,+X:#$
T8^l}Y
B
/** >8&fFq
* @return Returns the results. N*\ri0
*/ BU|)lU5)z
publicList<E> getResults(){ PP]7_h^2
return results;
IFW7MF9V
} '<'5BeU
%3.
np
public void setResults(List<E> results){ dh1 N/[
this.results = results; Hs6Kki1
} A@-U#UvN
dj}|EW4
public String toString(){ UzW]kY[A<
StringBuilder buff = new StringBuilder =CO'LyG
s[VYd:}se
(); c4zGQoeH:
buff.append("{"); olKM0K
buff.append("count:").append(count); *;Cpz[N
buff.append(",p:").append(p); 3J8M0W
buff.append(",nump:").append(num); /. H(&
buff.append(",results:").append OzR<jCOS
2`A[<