Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~D`R"vzw=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VUP.
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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 q?)5yukeF
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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 g& f)WQ(
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分页支持类: {7MY*&P$,
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java代码: /~7M @`1
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package com.javaeye.common.util; R>1oF]w
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import java.util.List; .6y*Z+Zg
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publicclass PaginationSupport { 2
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publicfinalstaticint PAGESIZE = 30; rc7c$3# X
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privateint pageSize = PAGESIZE; vRD(* S9^
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privateList items; Ov4 [gHy&
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privateint totalCount; g>'6"p;
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privateint[] indexes = newint[0]; c,ct=m.|6A
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privateint startIndex = 0; 'J!Gip ,
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public PaginationSupport(List items, int oL }d=x/
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totalCount){ ZtP/|P5@
setPageSize(PAGESIZE); odJE~\\hw
setTotalCount(totalCount); H!,V7R
setItems(items); RdL5VAD
setStartIndex(0); !vc5NKv#n
} VkJTcC:1
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public PaginationSupport(List items, int dS \n2Qb
,zH\P+*
totalCount, int startIndex){ 3,{;wJ
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setPageSize(PAGESIZE); 3[l\l5'm8
setTotalCount(totalCount); ";jAH GbO
setItems(items); v&%W*M0q@
setStartIndex(startIndex); xdY'i0fh
} I$)9T^Ra
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public PaginationSupport(List items, int d{(Rs.GuP
;- Vs|X
totalCount, int pageSize, int startIndex){ hp}rCy|01
setPageSize(pageSize); MrOtsX
setTotalCount(totalCount); ^L
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setItems(items); D62'bFB^
setStartIndex(startIndex); f`\J%9U _O
} f(K1,L:&7
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publicList getItems(){ |Xd&aQ
return items; sk0/3X*Q%
} vp d!|/
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publicvoid setItems(List items){ 7)Tix7:9S;
this.items = items; #^ .G^d(=
} `ZP[-: `
t*6C?zEAU
publicint getPageSize(){ IBNb!mPu%
return pageSize; Y2N$&]O{
} 9c1q:>|
#-R]HLW*
publicvoid setPageSize(int pageSize){ R iV]SgV9
this.pageSize = pageSize; 73tjDO7d
} d)XT> &
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publicint getTotalCount(){ ^<v.=7cL0
return totalCount; !ueh%V Ky
} ?6I`$ &OA
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publicvoid setTotalCount(int totalCount){ ?o/p}6
if(totalCount > 0){ 4xFAFK~lx
this.totalCount = totalCount; @:!% Z`
int count = totalCount / 0&r}'f?
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pageSize; =U:]x'g(
if(totalCount % pageSize > 0) CaoQPb*
count++; &;GoCU Le
indexes = newint[count];
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for(int i = 0; i < count; i++){ T).}~i;!
indexes = pageSize * {c&9}u$e
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} mcQ\"9 ;pY
}else{ I4c%>R
this.totalCount = 0; {z'Gg
} Ag1nxV1M$
} K:pG<oV|}
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publicint[] getIndexes(){ 2fPMZ7Zd3
return indexes; `0{qfms
} U?(,Z$:N
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publicvoid setIndexes(int[] indexes){ 5=4-IO6W[]
this.indexes = indexes; J=n^&y
} C|QJQ@bj0
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publicint getStartIndex(){ A+3=OBpkW0
return startIndex; 2"Y=*s
} 1fF\k#BE-%
;{n*F=%uC
publicvoid setStartIndex(int startIndex){ G0ENk|wbbj
if(totalCount <= 0) !A_KCM:Ym
this.startIndex = 0; 2b:I.
elseif(startIndex >= totalCount) mFIIqkUAL
this.startIndex = indexes v\kd78,
V<REcII.
[indexes.length - 1]; >rh<%55P`
elseif(startIndex < 0) %g4)f9>
this.startIndex = 0; Q?9eu%G6I
else{ uQWd`7
this.startIndex = indexes ^^)\|kW?
gti=GmL(L
[startIndex / pageSize]; $ g#d1u0q
} ZPY84)A_}
} e9B$"_ &2
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publicint getNextIndex(){ ?
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int nextIndex = getStartIndex() + "n<u(m8E
+,9Muf h
pageSize; '9|R7
if(nextIndex >= totalCount) B#4 J![BX
return getStartIndex(); e}L(tXZ
else ;[Hrpl
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return nextIndex; R"PO@v
} Q@UY4gA'
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publicint getPreviousIndex(){ %E2C4UbY
int previousIndex = getStartIndex() - .>(qZEF
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pageSize; ] m^ECA$
if(previousIndex < 0) .MRLAG
return0; iWn7vv/t
else 0+S'i82=M
return previousIndex; z7lbb*Xe
} nSU7,K`PM
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} c<qJs-C4;
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抽象业务类 ^EKf_w-v
java代码:
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/** !myF_cv}'
* Created on 2005-7-12 TC'^O0aZ_
*/ %w6lNl
package com.javaeye.common.business; .s@[-!
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import java.io.Serializable; 9'JkLgz;d+
import java.util.List; DzCb'#
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import org.hibernate.Criteria; !^A t{[U
import org.hibernate.HibernateException; ^kj%Ekt7
import org.hibernate.Session; ,1e@Y~eZ
import org.hibernate.criterion.DetachedCriteria; H\e<fi%Q
import org.hibernate.criterion.Projections; 7PI|~Ifi
import g/soop\:
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M
org.springframework.orm.hibernate3.HibernateCallback; 2c<phmiK
import *r]#jY4qx
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org.springframework.orm.hibernate3.support.HibernateDaoS [x|{VJ(h
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upport; r.zJ/Tk
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import com.javaeye.common.util.PaginationSupport; \t@|-`
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public abstract class AbstractManager extends n?A;'\cK
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HibernateDaoSupport { ,cFp5tV$
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privateboolean cacheQueries = false; u8@>ThPD
$(%t^8{a~G
privateString queryCacheRegion; sQe>LNp,G
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publicvoid setCacheQueries(boolean bDPT1A`F
gs77")K&
cacheQueries){ /-ky'S9
this.cacheQueries = cacheQueries; Z@`HFZJ
} E^.
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publicvoid setQueryCacheRegion(String b%,`;hy{
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queryCacheRegion){ YEqWTB|w
this.queryCacheRegion = Bhrp"l
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queryCacheRegion; /=qn1
} >j$CM:w
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publicvoid save(finalObject entity){ bx<7@
getHibernateTemplate().save(entity); /P|jHK|{
} 89)rss
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publicvoid persist(finalObject entity){ I2'UC)
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getHibernateTemplate().save(entity); _sCpyu
} 2xd G&}$fa
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publicvoid update(finalObject entity){ ]Z\.Vx
getHibernateTemplate().update(entity); 4<&`\<jZ
} qcfLA~y
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publicvoid delete(finalObject entity){ jM3{A;U2
getHibernateTemplate().delete(entity); <&rvv4*H
} YvK8;<k@-?
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a
publicObject load(finalClass entity, )y:~T\g
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finalSerializable id){ uIvE~<
return getHibernateTemplate().load cf0Dq~G
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(entity, id); O=St}B\!m
} OPwj*b:-m
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publicObject get(finalClass entity, dg1h<]T"9
.Eg>)
finalSerializable id){ @vaK-&|#$
return getHibernateTemplate().get Vj"B#
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(entity, id); eg-,;X#
} eJ#q! <
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publicList findAll(finalClass entity){ LQs2!]?HT
return getHibernateTemplate().find("from 6nRD:CH)X
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" + entity.getName()); pVt8z|p_;{
} &la;Vu"dp
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publicList findByNamedQuery(finalString ,m:YZ;J(Xd
}CA oB::&
namedQuery){ Uok?FEN
return getHibernateTemplate lM5Xw
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().findByNamedQuery(namedQuery); F%x8y
} j']m*aM1>
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publicList findByNamedQuery(finalString query, R;f!s/^)
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finalObject parameter){ gfs?H #
return getHibernateTemplate 'kK}9VKl
)sVz;rF<
().findByNamedQuery(query, parameter); 5/Q^p"
} <ok/2v
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publicList findByNamedQuery(finalString query, 0Q=4{*:?
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finalObject[] parameters){ w Maib3Q
return getHibernateTemplate fNc3&=]]
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().findByNamedQuery(query, parameters); RUmJ=i'4/
} Uax- z
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publicList find(finalString query){ hd.^ZD7
return getHibernateTemplate().find v3Y/D1jd"
*.AokY)_a
(query); <5A(rDij
} Im1e/F]
mh!;W=|/"
publicList find(finalString query, finalObject <IGQBu#ZH
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parameter){ tQB+_q
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return getHibernateTemplate().find =9e()j
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(query, parameter); ` IiAtS
} ,K8O<Mw8
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public PaginationSupport findPageByCriteria b:Dr_|
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(final DetachedCriteria detachedCriteria){ *Y6BPFE*4
return findPageByCriteria "*WzoRA={
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 9Nglt3J[
} <1VzQH!o
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public PaginationSupport findPageByCriteria %<JjftNQ
4,T!zT6&
(final DetachedCriteria detachedCriteria, finalint E@aR5S>
%zyO}
startIndex){ B i?DmrH
return findPageByCriteria vDz)q
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(detachedCriteria, PaginationSupport.PAGESIZE, 'Uew(o
(CS"s+y1
startIndex); &""~Pn8
} _K>cB<+d
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public PaginationSupport findPageByCriteria 7M<Ae
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(final DetachedCriteria detachedCriteria, finalint Sb+pB58&N
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pageSize, Qi#%&Jz>f
finalint startIndex){ Z16G
return(PaginationSupport) WaQCq0Enj
s!``OyI/Z
getHibernateTemplate().execute(new HibernateCallback(){ b&B<'Wb
publicObject doInHibernate SY_T\
}
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(Session session)throws HibernateException { gd-4hR
Criteria criteria = /Ws@YP
a= ;7
detachedCriteria.getExecutableCriteria(session); &96I4su
int totalCount = ^wCjMi(sj
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((Integer) criteria.setProjection(Projections.rowCount d>}pz
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()).uniqueResult()).intValue(); r}MXXn,f
criteria.setProjection ` ZXX[&C
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(null); F`3c uL[N
List items = dX: (%_Mn
at${^,&
criteria.setFirstResult(startIndex).setMaxResults z@^[.
:f?\ mVS+
(pageSize).list(); mdR:XuRD"t
PaginationSupport ps = |S|0'C*
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new PaginationSupport(items, totalCount, pageSize, hV])\t=yf
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startIndex); E8u:Fgs
return ps; I4ZL+a
} n;)!N
}, true); o-Pa3L=
} ge9j:S{
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public List findAllByCriteria(final RyKsM.
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DetachedCriteria detachedCriteria){ aErms-~
return(List) getHibernateTemplate 4<)%Esyb
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().execute(new HibernateCallback(){ : I28Zi*
publicObject doInHibernate ao#{N=mn
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(Session session)throws HibernateException { gEbe6!; q3
Criteria criteria = a H'iW)
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detachedCriteria.getExecutableCriteria(session); 6uW?xB9
return criteria.list(); ,J"6(nk
} EFu2&P
}, true); &WE| 9
} j1%o+#df
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public int getCountByCriteria(final l9"0Wu@_x
>
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DetachedCriteria detachedCriteria){ )4>M<BO
Integer count = (Integer) W'u6F-$2
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getHibernateTemplate().execute(new HibernateCallback(){ I?LJXo \O
publicObject doInHibernate sx IvL7jl
j+"i$ln+s
(Session session)throws HibernateException { ^EWkJW,Yc
Criteria criteria = :#1{c^i%3
z$$ E7i
detachedCriteria.getExecutableCriteria(session); >Lx,<sE
return [X]yj
IL` X}=L_
criteria.setProjection(Projections.rowCount G?CaCleG
q,3_)ZOq
()).uniqueResult(); |9T3" _MmJ
} nfET;:{
}, true); KWbnSL8
return count.intValue(); ?pn<lW8d
} CRf !tsj@
} F]DRT6)
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A Vf'"~?
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. > [d:0
用户在web层构造查询条件detachedCriteria,和可选的 cih@:=Qy
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ["Mq
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PaginationSupport的实例ps。 Dn~r~aR$g
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ps.getItems()得到已分页好的结果集 "S)2<tV
ps.getIndexes()得到分页索引的数组 <qjNX-|
ps.getTotalCount()得到总结果数 @q:v?AO
ps.getStartIndex()当前分页索引 ?=,4{(/)
ps.getNextIndex()下一页索引 ~XGBE
ps.getPreviousIndex()上一页索引 I[,tf!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q)vdDdRe_
zmd,uhNc:
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 )a"rj5~-
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一下代码重构了。 U$jw8I'.
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我把原本我的做法也提供出来供大家讨论吧: VQ wr8jXye
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首先,为了实现分页查询,我封装了一个Page类: \ldjWc<S
java代码: nF$n[:
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/*Created on 2005-4-14*/ )c|S)iJ7=z
package org.flyware.util.page; !-%fCg(B
I3sH8/*
/** gwVfiXR4
* @author Joa wMFo8;L
* -7jP'l=h
*/ J|4q9$
publicclass Page { n.9k<
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/** imply if the page has previous page */ v`&
privateboolean hasPrePage; %B9iby8)1
#m>Rt~(,S
/** imply if the page has next page */ :lf;CT6$
privateboolean hasNextPage; /IQl
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/** the number of every page */
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privateint everyPage; nADt8
~q0g7?}&
/** the total page number */ 9{&APxm
privateint totalPage; HqM>K*XKU
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/** the number of current page */ : (IPrQ
privateint currentPage; BC!n;IAe
MV8Lk/zd?A
/** the begin index of the records by the current 9J>b6
(EZ34,k'S
query */ ?naPti1GX
privateint beginIndex; dzA5l:5
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/** The default constructor */ W?+U%bIZ9
public Page(){ ?t;>]Wo;
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} >R|*FYam
/JP]5M)
/** construct the page by everyPage @q=l H
*=
* @param everyPage WY=RJe2
* */ _PTo!aJL
public Page(int everyPage){ 1|K>V;C
this.everyPage = everyPage; #$\cRLPg
} ;=rM Ii
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/** The whole constructor */ #Bo/1G=
public Page(boolean hasPrePage, boolean hasNextPage, lo }[o0X
@3D8TPH
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int everyPage, int totalPage, &uLxAw
int currentPage, int beginIndex){ iC U[X&
this.hasPrePage = hasPrePage; wLa^pI4p ^
this.hasNextPage = hasNextPage; r 5$(
this.everyPage = everyPage; *~p~IX{
this.totalPage = totalPage; [w iI
this.currentPage = currentPage; y&y(<
this.beginIndex = beginIndex; 5fh@nR
} Z=;+)
#,
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/** TmN}TMhZ
* @return >{DHW1kF?
* Returns the beginIndex. fVR:m`'Iq_
*/ eiLtZQ
publicint getBeginIndex(){ WA);Z=
return beginIndex; P1PP#>E-2
} &&1q@m,cP
Sr7+DCr
/** !*46@sb:
* @param beginIndex DNgQ.lV
* The beginIndex to set. wp/u*g
*/ 4fDo }~
publicvoid setBeginIndex(int beginIndex){ 'pE %'8R
this.beginIndex = beginIndex; |pIA9/~Z
} L_+0[A
Dl862$_Q
/** nMU#g])y)
* @return 3t(8uG<rL
* Returns the currentPage. 47Y|1
*/ Q37VhScs
publicint getCurrentPage(){ (wJtEoB9^
return currentPage; ;OYwZ
} E(G=~>P
Fa(}:Ug
/** `I$qMw,@
* @param currentPage ;qI5GQ {
* The currentPage to set. rT`D@
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*/ #vO3*-hs
publicvoid setCurrentPage(int currentPage){ o3H+.u$
this.currentPage = currentPage; Xco$
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} Tb-`0^y&X1
=N,KVMxw
/** y)3(
* @return MDkIaz\U
* Returns the everyPage. }9C5U>?
*/ "X']_:F1a
publicint getEveryPage(){ 9X&Xs/B
return everyPage; >/"XX,3
} m RCgKW<
R|Ft@]
/** RJs_ S
* @param everyPage {d$S~
* The everyPage to set. X.0/F6U
*/ dE5DH~ldV
publicvoid setEveryPage(int everyPage){ ;{|a~e?Y
this.everyPage = everyPage; @C=, >+D
} h3;Ij '
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/** ErC~,5dj;n
* @return Q}jbk9gM5
* Returns the hasNextPage. f}4c#x
*/ 'Rfvr7G/?
publicboolean getHasNextPage(){ V>P\yr?
return hasNextPage;
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} Ja-D}|;
@];#4O
/** MW9B
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* @param hasNextPage tYfhKJzGC
* The hasNextPage to set. k?Jzy
*/ hvBuQuk)
publicvoid setHasNextPage(boolean hasNextPage){ -b@E@uAX/
this.hasNextPage = hasNextPage; hE:P'O1
} ;hs:wLVa"
v >3ctP{
/** ;J\{r$q
* @return #},]`"n\
* Returns the hasPrePage. qn@Qd9Sf
*/ 7kn=j6I
publicboolean getHasPrePage(){ u2<:mu[|P
return hasPrePage; c7\bA7.
} gx[#@(
p)ZlQ.d#Y
/** ?l,i(I
* @param hasPrePage +bm2vIh$
* The hasPrePage to set.
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*/ (p} N9n$
publicvoid setHasPrePage(boolean hasPrePage){ r"fu{4aX
this.hasPrePage = hasPrePage; va8:QHdU
} .WL507*"Ce
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/** F__>`Dol
* @return Returns the totalPage. mS~3 QV
* H@IX$+;z
*/ n 2#uH
publicint getTotalPage(){ cb%w,yXw
return totalPage; q){]fp.,@
} 81W})q8
4BEVG&Ks
/** _;01/V"q6
* @param totalPage Q,\lS
* The totalPage to set. KvilGh10
*/ 8gC(N3/E"
publicvoid setTotalPage(int totalPage){ ]^
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this.totalPage = totalPage; ZuS+p0H"
} 2L<TqC{,-
]VJcV.7`
} 4d]
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iI&SI#;
_
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 =As'vt
0
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个PageUtil,负责对Page对象进行构造: @oRYQ|.R
java代码: ,A6*EJ\w
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/*Created on 2005-4-14*/
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package org.flyware.util.page; &I(|aZx?J
)%j)*Ymz;
import org.apache.commons.logging.Log; ==FzkRA)
import org.apache.commons.logging.LogFactory; X_!mZ\H7
/@#)j(
eY/
/** ]}v`#-Px(
* @author Joa rW\~s TH
* #-lk=>
*/ [/#n+sz.A
publicclass PageUtil { %7|qnh6
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privatestaticfinal Log logger = LogFactory.getLog Mx r#
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(PageUtil.class); /asyj="N7
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/** 0>e>G (4(8
* Use the origin page to create a new page :&:>sd(QD
* @param page B!tte)
* @param totalRecords rz7yAm
* @return ]`4QJ;#
*/
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publicstatic Page createPage(Page page, int *<0g/AL
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totalRecords){ 2! 6Kzq
return createPage(page.getEveryPage(), y mE`V
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page.getCurrentPage(), totalRecords); _SFD}w3b$
} g<lX Xj2
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/** 0~S<}N
* the basic page utils not including exception mMjVbeh[
LAwS8t',
handler un9o~3SF<
* @param everyPage AT9SD vJ
* @param currentPage 9Akwr}
* @param totalRecords J2cNwhZ
* @return page $\K(EBi#G
*/ x4( fW\
publicstatic Page createPage(int everyPage, int & {/u>,
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currentPage, int totalRecords){ Fh/C{cX9g
everyPage = getEveryPage(everyPage); =H?Nb:s
currentPage = getCurrentPage(currentPage); G?_,(
int beginIndex = getBeginIndex(everyPage, 5g5pzww
,pG63&?j
currentPage); '#Fh
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int totalPage = getTotalPage(everyPage, U92hv~\
w`v\/a_
totalRecords); AdYQhF##
boolean hasNextPage = hasNextPage(currentPage, @"EX%v.
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totalPage);
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boolean hasPrePage = hasPrePage(currentPage); X'F$K!o*,:
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returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, vSL{WT]m
currentPage, h/VYH(Tj
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beginIndex); 2M1mdkP3
} Oxvw`a#
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privatestaticint getEveryPage(int everyPage){ `&6]P :_qp
return everyPage == 0 ? 10 : everyPage; puyL(ohem
} j w462h
v;8XRR:
privatestaticint getCurrentPage(int currentPage){ lpM{@JC
return currentPage == 0 ? 1 : currentPage; Smux&e
} ~zX5}U<R
bDNd
m-
privatestaticint getBeginIndex(int everyPage, int )gLasR.1
c8s/`esA
currentPage){ od fu7P_
return(currentPage - 1) * everyPage; NEH$&%OV?
} y$"L`*W
N{yZk"fq:6
privatestaticint getTotalPage(int everyPage, int =>J#_Pprn
[P,nW/H
totalRecords){ {ULnQ6@
int totalPage = 0; Fo=6A[J
]rm=F]W/n
if(totalRecords % everyPage == 0) # 0(\s@r.
totalPage = totalRecords / everyPage; }>:X|4]
else TExlGAHo+O
totalPage = totalRecords / everyPage + 1 ; 2fk
T{M:)}V
return totalPage; F&~vD
} pp`U]Q5"gX
*~L]n4-
privatestaticboolean hasPrePage(int currentPage){ t*#&y:RG
return currentPage == 1 ? false : true; I$LO0avvH2
} jY.%~Y1y
e-CW4x
privatestaticboolean hasNextPage(int currentPage, zE/(F;> FV
J"MJVMo$T
int totalPage){ yB1>83!q
return currentPage == totalPage || totalPage == u2Obb`p S
?rDwYG(u]@
0 ? false : true; a40BisrD~6
} 7KIQ)E'kG|
8IH gsW";
I2T2'_I
} k#&SWp=
co80M;4
:
eFc.>KoD
ZM?r1Z4
'
^^K#f8
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。 >>Di
mK-:laIL"
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 {LDb*'5Cy
h_L '_*
做法如下: cFvx*n
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #VE$C3<
HWBom8u0
的信息,和一个结果集List: 5aNDW'z`f
java代码: lg+g:o
Sq,ty{j2%
Qg!*=<b
/*Created on 2005-6-13*/ @k,(i=**
package com.adt.bo; 7p$*/5fk
#O+]ydvT
import java.util.List; #^ #i]{g
ZtoE=7K
import org.flyware.util.page.Page; E=NY{| >
{SJ7Yfs
/** ?<QFW#:)
* @author Joa BaAb4{
*/ :nUsC+oBS
publicclass Result { QO/7p]$_
\[EWxu
private Page page; n #I}!x>2
|/;5|
z
private List content; 4?&a?*M
M3 u8NRd5|
/** %U7f9
* The default constructor 4/WCs$
*/ QB,ad
public Result(){ 2v1&%x:y#
super(); -Wk"o?}q
} L?+|%[
#>B1$(@
/** pH%c7X/[3L
* The constructor using fields MA#!<b('
* Zr;=p"cXr
* @param page Y{|yB
* @param content q:EQ,
*/ 2kq@*}ys
public Result(Page page, List content){ Xy<f_
this.page = page; t|QMS M?s
this.content = content; !\O,dq
} _ n4ma
F@bCm+z-
/** =Gz>ZWF
* @return Returns the content. ,{*fOpn
*/ @I6 A9do
publicList getContent(){ KB*=a
return content; EsB'nf r
} 2(//slP
$yFuaqG`Wo
/** KocXSh U
* @return Returns the page. {WOfT6y+
*/ N|2
public Page getPage(){ B1#>$"_0}=
return page; > C&<dO#i
} M~F2cXW
WC*:\:mh
/** e*6` dz@
* @param content G%jJ>T4
* The content to set. Q8cPKDB
*/ wg_CI,Kq
public void setContent(List content){ t>@3RBEK
this.content = content; B^~Bv!tHWr
} hg'!
'OW"*b
/** ]u ~Fn2
* @param page m+{: ^
* The page to set. GSnHxs)
*/ v^_]W3K
publicvoid setPage(Page page){ bvS\P!m\c
this.page = page; C,vc
aC?
} ,<r 3Z$G
} "sX?wTag
SJ7=<y}[d
(G%gVk]
[Ms{J!^q
WTv\HI2X
!
2. 编写业务逻辑接口,并实现它(UserManager, I jztj
DLVs>?Y
UserManagerImpl) [HiTR !o*
java代码: <?7,`P:h[
=1OAy`8
`4$Qv'X*
/*Created on 2005-7-15*/ p<fgUVR
package com.adt.service; 7"NJraQ6
:fKz^@mY4
import net.sf.hibernate.HibernateException; YkAWKCOni
`Mp7})
import org.flyware.util.page.Page; Is6 _
l@/kPEh
import com.adt.bo.Result; aC
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7oLf5V1~
/** }\L!;6oy
* @author Joa yxWMatZ2
*/ SJc@iffS
publicinterface UserManager { KM(9&1/
jP.b oj_u*
public Result listUser(Page page)throws 9`n)"r
S@zkoj@
HibernateException; )'dH}3Ba
R{KIkv
} )^>XZ*eK
t:sq*d
SLjf<.S
S}Y|s]6
{r2|fgi
java代码: zpr@!76
C9Z\G 3
%x8`fm
/*Created on 2005-7-15*/ <eFAI}=s
package com.adt.service.impl; {AL9o2
akCo+ @
import java.util.List; hd
;S>K/C
ck_fEF
import net.sf.hibernate.HibernateException; b
hr E
?(ls<&s{w
import org.flyware.util.page.Page; grxl{uIC8
import org.flyware.util.page.PageUtil; P:,
x?T?J^
T\
}v$A03
import com.adt.bo.Result; ?-:: {2O)
import com.adt.dao.UserDAO; *:tjxC
import com.adt.exception.ObjectNotFoundException; :Ip:sRz
import com.adt.service.UserManager; jM1%6
]F*a PV
/** CndgfOF
* @author Joa 27 145
*/ ;!JX-J q
publicclass UserManagerImpl implements UserManager { fw|+7 O
C| L^Ds0
private UserDAO userDAO; $7DcQ b9
$n#Bi.A
j
/** %::deV7
* @param userDAO The userDAO to set. dbuJ~?D,
*/ 6+B{4OY
publicvoid setUserDAO(UserDAO userDAO){ "$IXZ
this.userDAO = userDAO; =i^<a7M~
} mh#FYSp
KA-/k@1&
/* (non-Javadoc) J1]w*2
* @see com.adt.service.UserManager#listUser N>pmhskN?
H1%[\X?=
(org.flyware.util.page.Page) g;!@DVF$
*/ "ryk\}*<
public Result listUser(Page page)throws ^L-w(r62<
#;"D)C
HibernateException, ObjectNotFoundException { :IR9=nhS]
int totalRecords = userDAO.getUserCount(); $S=~YzO
if(totalRecords == 0) Ph#F<e(9
throw new ObjectNotFoundException *fH_lG%
pba8=Z
("userNotExist"); 7.e7Fi{
page = PageUtil.createPage(page, totalRecords); Vl 19Md
List users = userDAO.getUserByPage(page); 95^i/6Gl!P
returnnew Result(page, users); 4OOn, 09
} <{cNgKd9
JYg% ~tW'
} 7*>S;$
:`Uyn!w
oO#xx)b
mo;)0Vq2l
p>:ef<.i
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G=Hf&l
6vgBqn[
询,接下来编写UserDAO的代码: 5`E`Kb+@
3. UserDAO 和 UserDAOImpl: '{0[&i*
java代码: &(1H!
5K ,#4EOV
IObx^N_K
/*Created on 2005-7-15*/ 3xzkZ8]/
package com.adt.dao; k]Alp;hVd
)Ab6!"'
import java.util.List; Z%+BWS3YqY
C1T=O
import org.flyware.util.page.Page; a4T~\\,dZ>
l 70,Jo?78
import net.sf.hibernate.HibernateException; i>Fvmw
P1i*u0a
/** ^}o7*
* @author Joa %-#
qO
*/ SY'2A)
publicinterface UserDAO extends BaseDAO { Gg9VS&VI
@q&|MMLt
publicList getUserByName(String name)throws ?L@@;tt
2f|6z-Z
HibernateException; 4O`6h)!NQ
l801`~*gO
publicint getUserCount()throws HibernateException; cGE=.
Z6Nj<2u2
publicList getUserByPage(Page page)throws
(A29ZH
-!J2x8Ri
HibernateException; W}XYmF*_?
`l>93A
} -=$% {
/Fv/oY
0%s3Mp6H
L`UG=7r q
Q PFeBl
java代码: <t{?7_ 8
s) Cpi
JBR[;
zM
/*Created on 2005-7-15*/ 'ySljo*It
package com.adt.dao.impl; ~n[b^b
g4:VR:o
import java.util.List; %5JW<9
9<|m4
import org.flyware.util.page.Page; U_}7d"<| ?
B(j02<-
import net.sf.hibernate.HibernateException; 8F zHNG
import net.sf.hibernate.Query; hCzjC|EO~
#(%t*"IY;
import com.adt.dao.UserDAO; )n7|?@5U
|l|_dn
/** 9W*.lf
* @author Joa V43nws"4
*/ 3{<R5wUo"
public class UserDAOImpl extends BaseDAOHibernateImpl tTotPPZf}
YP[LQ>
implements UserDAO { 'nRp}s1^[
NJZXs_%>$
/* (non-Javadoc) n6b3E*
* @see com.adt.dao.UserDAO#getUserByName 6*ZU}xT
[}>#YPZ
(java.lang.String) 1~%o}+#-
*/ &*B>P>x
publicList getUserByName(String name)throws izCaB~{/
- $U@By<SJ
HibernateException { u]HS(B,ht
String querySentence = "FROM user in class mZwi7s&u
W*k`
com.adt.po.User WHERE user.name=:name"; v&xKi>Ail
Query query = getSession().createQuery NB EpM
$ye^uu;Z
(querySentence); xXF2"+
query.setParameter("name", name); (NX)oP
return query.list(); ]}Pl%.
} [ S5bj]D
hwiKOP
/* (non-Javadoc) HOE2*4r
* @see com.adt.dao.UserDAO#getUserCount() 3&es]1b
*/ }wG,BB %N
publicint getUserCount()throws HibernateException { wGPotPdE2
int count = 0; EMLx?JnP
String querySentence = "SELECT count(*) FROM osl=[pm
\}Dpb%^\
user in class com.adt.po.User"; D%-{q>F!gf
Query query = getSession().createQuery JwZ?hc
TfJL+a0
(querySentence); kLJlS,nh\r
count = ((Integer)query.iterate().next wG+=}1X
o]A XT8
()).intValue(); ;Xqn-R
return count; d7* CwY9"
} XdpF&B&K7Q
[4p=X=B
/* (non-Javadoc) (Akd8}nf~
* @see com.adt.dao.UserDAO#getUserByPage `)6>nPr7P
?cJY
B)
(org.flyware.util.page.Page) ~z5@V5z
*/ F)
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publicList getUserByPage(Page page)throws \/!ZA[D|E\
j")FaIM
HibernateException { K"L_`.&Q
String querySentence = "FROM user in class U
IfH*6X
W6vf=I@f
com.adt.po.User";
lWbZ=x_0
Query query = getSession().createQuery +@0TMK,P
yO=p3PV d
(querySentence); <;%0T
xK|U
query.setFirstResult(page.getBeginIndex()) tw=K&/@^O
.setMaxResults(page.getEveryPage()); x=.tiM {#
return query.list(); y0<Uu
} I:i<>kG
=L"^.c@
} 40 2x<H
ym\(PCa5`
ryg4hHspl
[ByQ;s5tY
lV\lj@
至此,一个完整的分页程序完成。前台的只需要调用 6UlF5pom
UFe(4]^
userManager.listUser(page)即可得到一个Page对象和结果集对象 [Eu];
ltoqtB\s
的综合体,而传入的参数page对象则可以由前台传入,如果用 r0\?WoF2C
'<7S^^ax
webwork,甚至可以直接在配置文件中指定。
O}C)~GU
,^ 7 CP
下面给出一个webwork调用示例: zie=2
java代码: If;R?j0;Q
4O(@'#LLz
r,4lqar;E
/*Created on 2005-6-17*/ OEnDsIhq
package com.adt.action.user; 1}}>Un`U5,
`B:"6nW6
import java.util.List; o-z &7@3Hu
P?
(vW&B
import org.apache.commons.logging.Log; :I
\9YzSs@
import org.apache.commons.logging.LogFactory; @DuK#W"E u
import org.flyware.util.page.Page; 03([@d6<E
mRwT_(;t
import com.adt.bo.Result; ^P?vkO"pB?
import com.adt.service.UserService; WS:5MI,OL
import com.opensymphony.xwork.Action; W`rMtzL5
UQI
f}iR
/** o>F*Itr{
* @author Joa OQScW2a&
*/ Q`A6(y/s?
publicclass ListUser implementsAction{ @*(4dt:V
OP%?dh]
privatestaticfinal Log logger = LogFactory.getLog T 6Ctf#
3?.1nGu
(ListUser.class); s]H^wrg&
xx }GOY.J
private UserService userService; G 4qy*.
&Jy)U
private Page page; [
]^X`R
FRZs[\I|iT
privateList users; g$FEEDF
0/ !,Dn
/* LnFWA0y
* (non-Javadoc) J[@um:
* 3F+Jdr'
* @see com.opensymphony.xwork.Action#execute() BAV>o|-K
*/ C!&y
publicString execute()throwsException{ .VM3D0aV
Result result = userService.listUser(page); gsPl _
page = result.getPage(); UXH"si:
users = result.getContent(); P=`1 rjPE
return SUCCESS; 8uch i
} /(?@mnq_
oY=1C}
/** 3A,rHYS
* @return Returns the page. "NzD1k6.L
*/ V*RdDF7
public Page getPage(){ }T.?c9l X
return page; ?WpenUWk
} )R?;M
|0.Xl+7
/** ? 2#(jZ# 2
* @return Returns the users. g=l:cVr8y
*/ XiQkrZ
publicList getUsers(){ QTmZ(>z
return users; ,=BLnsg
} .Cz %:%9
eV7u*d?
/** ^"i~DC
* @param page wX,F`e3"/
* The page to set. ;%Hf)F
*/ 8)yI<`q6
publicvoid setPage(Page page){ 5$rSEVg9
this.page = page; h}L}[
} fuX'~$b.fA
bZ 443SG
/** T$+-IAE
* @param users +4qU>
* The users to set. ZA(T
*/ :I1_X
publicvoid setUsers(List users){ \or G63T:
this.users = users; .*YD&(
} ycAKK?O*
a9U_ug58
/** )92r{%N
* @param userService o[1ylzk}+
* The userService to set. 8K"+,s(%R
*/ o "z@&G" ^
publicvoid setUserService(UserService userService){ (% _n!ip^
this.userService = userService; )G1P^WV4
} 1HT_
} mXzrEI
Wu1{[a|
?rYT4vi
b)#Oc,
;GGK`V
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, 'gso'&Uaj
uz30_aH
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 sEc;!L
%~xGkk"I
么只需要: kAA>FI6
java代码: H%F>@(U
:G5uocVk
\e3`/D
<?xml version="1.0"?> ^:=f^N=^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork @>Mxwpl?
2aN<w'pA
1.0//EN" "http://www.opensymphony.com/xwork/xwork- U/l?>lOD\
;gg\;i}^
1.0.dtd"> 13hE}g;.
K(}AX+rIg
<xwork> MrRaU x6z
1.<q3q
<package name="user" extends="webwork- _<c$)1
%
ps$qB'
interceptors"> WjSc/3Qy
"Z=5gj
<!-- The default interceptor stack name Dnf*7)X
eLD|A=X?
--> 5ExDB6Bx@y
<default-interceptor-ref PxFWJ?=
D L'iS
name="myDefaultWebStack"/> 8flOq"uK^
[U@;\V$
<action name="listUser" _ *f
``VW;l{
class="com.adt.action.user.ListUser"> k^"bLf(4
<param yp.[HMRD
v"& pQ
name="page.everyPage">10</param> a|7a_s4(
<result 1BHG'y
y
!$alE
name="success">/user/user_list.jsp</result> VZ&
A%UFC
</action> '(GiF
.xhK'}l[
</package> X1{[}!
B~
S6R
</xwork> 'B5^P
?S$i?\Qh
l:#-d.z#
XQ%4L-rhN
YKmsQ(q`N
%WTEv?I{Ga
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 d[p;T\?"
L|-98]8>
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。 Q6gt+FKU9
1923N]b
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Y6i _!z[V[
G7!W{;@I
m%;D
DGW+>\G
NA3\
我写的一个用于分页的类,用了泛型了,hoho osARA3\Xt
tZ`Ts}\e
java代码: ML;*e "$
m7EcnQf
-HSs^dP`
package com.intokr.util; g_5Q A)4x
gz2\H}
import java.util.List; o8e?J\?
n1
6 `y}
/** nOx4<Wk&
* 用于分页的类<br> nJ4pTOc
* 可以用于传递查询的结果也可以用于传送查询的参数<br> .itw04Uru
* toN^0F?Qm
* @version 0.01 H~ZV*[A`
* @author cheng sGh(#A0Pt
*/ 2(5ebe[
public class Paginator<E> { qTZFPfyU
privateint count = 0; // 总记录数 Hbv6_H
privateint p = 1; // 页编号 qW:HNEiir
privateint num = 20; // 每页的记录数 kmzH'wktt
privateList<E> results = null; // 结果 3(C\.oRc
gs!(;N\j|
/** .ERO|$fv
* 结果总数 I>L-1o|^
*/ 4DZ-bt'
publicint getCount(){ zOg7raIa
return count; Y0?5w0{
} ()&~@1U
wtje(z5IL
publicvoid setCount(int count){ Eu"_MgD
this.count = count; r.7$&BCng
} )95f*wte
`+6R0Ch
/** W9NX=gE4
* 本结果所在的页码,从1开始 *CHI2MB
* dy_:-2S
* @return Returns the pageNo. =zQN[
*/ ;WR,eI..
publicint getP(){ Ft}@1w5
return p; {s. = )0V
} w]N!S;<N
%|s+jeUDn|
/** tcxcup%
* if(p<=0) p=1
%iV^S!e
* boDt`2=
* @param p %^RN#_ro(3
*/ ]_N|L|]M
publicvoid setP(int p){ 95el'K[R
if(p <= 0) )"Ztlhs`#
p = 1; d!eYqM7-G
this.p = p; x.S3Zi}=
} M4as
;!(<s,c#:
/** 9(QJT}qC
* 每页记录数量 Gea\,{E9xA
*/ '],J$ge
publicint getNum(){ @S|XGf
return num; 1GzAG;UUo6
} y5!KX AQ%
a+n0|CvF
/** -'6Dg
* if(num<1) num=1 yPq'( PV
*/ AK@9?_D
publicvoid setNum(int num){ /Rl6g9}
if(num < 1) 3Z1CWzq(
num = 1;
O({2ivX
this.num = num; ` V##Y
} .V,@k7U,V
41&\mx
/** p,#o<W
* 获得总页数 ob8qe,_'
*/ 4:FK;~wM&x
publicint getPageNum(){ ~@}Bi@*
return(count - 1) / num + 1; 5{g?,/(
} %7|9sQ:
`nu''B
H
/** FJMrs[
* 获得本页的开始编号,为 (p-1)*num+1 \-g)T}g,I
*/ 9 AJ(&qY(
publicint getStart(){ <7~'; K
return(p - 1) * num + 1; A}l3cP;
`#
} WPQ fhr#|
a|X a3E
/** ui?
* @return Returns the results. 4t=G
*/ wRVUu)
publicList<E> getResults(){ RCpR3iC2
return results; W)bLSL]`E
} ueUuJxq)
7j-4TY~
public void setResults(List<E> results){ 'tH_p
this.results = results; [@.!~E)P
} ')cMiX\v
P5UL4uyl
public String toString(){ :.Wr{"`
StringBuilder buff = new StringBuilder |!4K!_y
1eF3`
(); .6Pw|xu`Pw
buff.append("{"); d$1@4r
buff.append("count:").append(count); ,5h)x"s
buff.append(",p:").append(p); I`!<9OTBj
buff.append(",nump:").append(num); 6^`1\
#f
buff.append(",results:").append F'21jy&
BI%$c~wS
(results); H:V2[y8\
buff.append("}"); %xI p5h]
return buff.toString(); t7aefV&_,
}
XwJ7|cB
EFM5,gB.m
} fumm<:<CLO
[DI+~F
>G25m'&,7