Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 QU t!fF@t
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <~d N23)
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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 xInWcQ
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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 `JRdOe
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分页支持类: *b&|
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java代码: J8jbtL O'
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package com.javaeye.common.util; PF.HYtZqK
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import java.util.List; V|7 cdX#H
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publicclass PaginationSupport { mU!c;O
FQ5# v{
publicfinalstaticint PAGESIZE = 30; %]-tA,u
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privateint pageSize = PAGESIZE; {S?.bT%&
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privateList items; DD1S]m
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privateint totalCount; 9I,Trk@&
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privateint[] indexes = newint[0]; 1peN@Yk2W
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privateint startIndex = 0; Q]8r72uSk
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public PaginationSupport(List items, int 8W{R&Z7aL
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totalCount){ EB\\
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setPageSize(PAGESIZE); F
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setTotalCount(totalCount); avQwbAh[
setItems(items); R8HFyP
setStartIndex(0); 8qT/1b
} ;yr'K
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public PaginationSupport(List items, int ?n}L+|
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totalCount, int startIndex){ BwR)--75
setPageSize(PAGESIZE); IMj{n.y4
setTotalCount(totalCount); ;*8$BuD
setItems(items); i]P]o)
setStartIndex(startIndex); Na4\)({
} 0VPa=AW
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public PaginationSupport(List items, int dI`b AP;\
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totalCount, int pageSize, int startIndex){ !^y'G0
setPageSize(pageSize); :>|[ o&L
setTotalCount(totalCount); ).\%a
h
setItems(items); `,J\E<4J
setStartIndex(startIndex); L9T|* ?||
} _s^sZ{'2_
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publicList getItems(){ T5ol2
return items; :p89J\
} 7v{Dwg
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publicvoid setItems(List items){ ct`89~"
this.items = items; [j):2
} -{^Gzui
vForj*Xo
publicint getPageSize(){ b^0=X!bg
return pageSize; q%nWBmPZ~y
} BRzrtK
7"1M3P5*8
publicvoid setPageSize(int pageSize){ gkDB8,C<j
this.pageSize = pageSize; o<Q~pd#Ip,
} Wh,p$|vL
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publicint getTotalCount(){ L:7%W dyh
return totalCount; 3{CXIS
} p~qdkA<
MFRM M%`
publicvoid setTotalCount(int totalCount){ }}<^fM
if(totalCount > 0){ s$A|>TOY
this.totalCount = totalCount; +ps(9O/B>
int count = totalCount / 1jDN=hIl
QN":Qk(,q
pageSize; r+>gIX+Fl
if(totalCount % pageSize > 0) 0`:0m/fsU
count++; NbH;@R)L
indexes = newint[count]; !IcPO
for(int i = 0; i < count; i++){ af)L+%Q%R
indexes = pageSize * .^eajb`:
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i; cJMp`DQzc
} Nzf tc
}else{ Lc=t,=OhGe
this.totalCount = 0; m;'ebkq
} w=,bF$:fIW
} S/V%<<[>p]
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publicint[] getIndexes(){ =XVw{\#9 b
return indexes; +JsMYv
} bZLY#g7L"
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publicvoid setIndexes(int[] indexes){ y2cYRHN[X}
this.indexes = indexes; !#3v<_]#d
} *jM]:GpyoU
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publicint getStartIndex(){ ^?}-x
return startIndex; 1N,</<"
} qx|~H'UuBN
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publicvoid setStartIndex(int startIndex){ UyENzK<%u
if(totalCount <= 0) ~6DaM!
this.startIndex = 0; &sJ -&7YZ
elseif(startIndex >= totalCount) \8g'v@$wG
this.startIndex = indexes <- L}N '
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[indexes.length - 1]; ]jjHIFX
elseif(startIndex < 0) zc K`hS
this.startIndex = 0; {u~JR(C:
else{ ]lqLC
this.startIndex = indexes 9(6f:D
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[startIndex / pageSize]; VYbH:4K@%
} ^,}1^?*
} zcGmru|k
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publicint getNextIndex(){ >cJix
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int nextIndex = getStartIndex() + 0fu*}v"
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pageSize; cDS\=Bf
if(nextIndex >= totalCount) 52ExRG S
return getStartIndex(); 0Xb,ne
7
else 2ci[L:U
return nextIndex; z.lIlp2:
} =U'!<w<-
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publicint getPreviousIndex(){ AO,
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int previousIndex = getStartIndex() - C cPOK2
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pageSize; ncrg`<'/,
if(previousIndex < 0) Uo?4o*}
return0; qF\w#nG
else /z!Tgs4
return previousIndex; r3qKT
} PzOnS
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} bMn)lrsX
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抽象业务类 ;.'?(iEB
java代码: )pSA|Qt N
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/** Dj>eAO>
* Created on 2005-7-12 |sd G<+
*/ .' }jd#
package com.javaeye.common.business; yIhPB8QL
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import java.io.Serializable; BmKf%:l}
import java.util.List; fLnwA|n=
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import org.hibernate.Criteria; >$7x]f
import org.hibernate.HibernateException; }4N'as/ZO
import org.hibernate.Session; _V4O#;%?
import org.hibernate.criterion.DetachedCriteria; 1RJFPv
import org.hibernate.criterion.Projections; :.4O
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import P0y DL:X[
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org.springframework.orm.hibernate3.HibernateCallback; +j{(NwsX
import WG A1XQ{
MA,*$BgZ
org.springframework.orm.hibernate3.support.HibernateDaoS U$mDAi$
=* G3Khz!
upport;
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import com.javaeye.common.util.PaginationSupport; :h5G|^
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public abstract class AbstractManager extends U|]cB
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HibernateDaoSupport { ;Ax-f04gG
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privateboolean cacheQueries = false; Z/%FQ
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privateString queryCacheRegion; g]lEG>y1R
ep=r7Mft
publicvoid setCacheQueries(boolean u Jqv@GFv
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cacheQueries){ ^#d\HI
this.cacheQueries = cacheQueries; GuO}CQs^W
} <mQXS87
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publicvoid setQueryCacheRegion(String `wXK&R<`
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queryCacheRegion){ iqvLu{
this.queryCacheRegion = I)rO|
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queryCacheRegion; ~f h
} 8
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publicvoid save(finalObject entity){ >E>yA d
getHibernateTemplate().save(entity); xIGq+yd(
} $DoR@2~y
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publicvoid persist(finalObject entity){ =p8uP5H
getHibernateTemplate().save(entity); -B;#pTG
} 1(gs({
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publicvoid update(finalObject entity){ $D1ha CL
getHibernateTemplate().update(entity); }T@=I&g;
} ob\-OMNs@
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publicvoid delete(finalObject entity){ 'OsZD?W{
getHibernateTemplate().delete(entity); )A\
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} ,AP0*Ln
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publicObject load(finalClass entity, w*-42r3,'
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finalSerializable id){ oX|T&"&
return getHibernateTemplate().load e9o\qEm
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(entity, id); 1Cw]~jh
} }R%H?&P
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publicObject get(finalClass entity, 6kYluV+j
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finalSerializable id){ {y9G
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return getHibernateTemplate().get +>"s)R43
1,-C*T}nR
(entity, id); ye(b 7CX
} l~i?
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publicList findAll(finalClass entity){ dH y9
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return getHibernateTemplate().find("from wXIRn?z
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" + entity.getName()); aV\i3\da
} Vu3DP+u|i
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publicList findByNamedQuery(finalString Xs~'M/>
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namedQuery){ Fi/iA%,
return getHibernateTemplate }bb,Iib
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().findByNamedQuery(namedQuery); J$#T_4 )
} 24 [KGp
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publicList findByNamedQuery(finalString query, 8!E.3'jb
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finalObject parameter){ 'Aq^z%|
return getHibernateTemplate P([!psgu
], lLDUZ\
().findByNamedQuery(query, parameter); C%z)D1-
} #`VAw ) eV
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publicList findByNamedQuery(finalString query, Sq5,}oT_{j
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finalObject[] parameters){ B[N]=V
return getHibernateTemplate TTXF
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().findByNamedQuery(query, parameters); T#ls2UL*xh
} Xq? >a+B
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publicList find(finalString query){ l77 -I:
return getHibernateTemplate().find =A'>1N
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(query); {KG}m'lx
} riIubX#
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publicList find(finalString query, finalObject \D@j`o
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parameter){ I~&*^q6 |
return getHibernateTemplate().find GHsDZ(d3.
s<!A<+Sh
(query, parameter); Nf| 0O\+%y
} 9^a|yyzL
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public PaginationSupport findPageByCriteria ~su>RolaX
?(9*@
(final DetachedCriteria detachedCriteria){ =t,oj6P~
return findPageByCriteria hIV9 .{J
eKiDc=@
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3~`P8 9
} .RroO_H
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public PaginationSupport findPageByCriteria <f>77vh0
&]TniQH
(final DetachedCriteria detachedCriteria, finalint bJ:5pBJ3
=Zj
7dn;EN
startIndex){ Ti? "Hr<W
return findPageByCriteria m6i ,xn
*$A`+D9
(detachedCriteria, PaginationSupport.PAGESIZE, hkPMu@BI
DGHSyB^+1
startIndex); c}@E@Y`@w
} OeQ[-e
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public PaginationSupport findPageByCriteria Vh0cac|X
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(final DetachedCriteria detachedCriteria, finalint lV'?X%
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pageSize, ^&;,n.X5Z
finalint startIndex){ K@p9_K8
return(PaginationSupport) /we]i1-9
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getHibernateTemplate().execute(new HibernateCallback(){ lat5n&RP Y
publicObject doInHibernate n.l#(`($4
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(Session session)throws HibernateException { ;Rv WF )
Criteria criteria = o(tJc}Mh+(
@fA{;@N
detachedCriteria.getExecutableCriteria(session); fq>{5ODO
int totalCount = |eRE'Wd0
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((Integer) criteria.setProjection(Projections.rowCount kwp%5C-S
+
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()).uniqueResult()).intValue(); ozY$}|sjDT
criteria.setProjection H^'%$F?Ss
G&h@
(null); F:jNv3W1
List items = _n:RA)4*
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criteria.setFirstResult(startIndex).setMaxResults \:@6(e Bh
_OGv2r
(pageSize).list(); r`-8+"P
PaginationSupport ps = l$5nv5r
.c>6}:ye
new PaginationSupport(items, totalCount, pageSize, 9 m8KDB[N
* K$U[$s
startIndex); *-ys}sX
return ps; 1V]ws}XW
} GG%;~4#2
}, true); zsuqRM
"
} t;+b*S6D
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public List findAllByCriteria(final jOCV)V9}
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DetachedCriteria detachedCriteria){ nP[Z6h
return(List) getHibernateTemplate K Zg NL|
a;bmlV04
().execute(new HibernateCallback(){ gdCit-3
publicObject doInHibernate 8Dl(zY K;
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(Session session)throws HibernateException { ITl>HlS
Criteria criteria = p9jC-&:
(Q*x"G#4>
detachedCriteria.getExecutableCriteria(session); V0D&bN*
return criteria.list(); 8Vz!zYl
} @_t=0Rc
}, true); FI: H/e5[
} Zrwd
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public int getCountByCriteria(final wdt2T8`I/
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DetachedCriteria detachedCriteria){ _N:$|O#
Integer count = (Integer) e<uf)K=(C
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getHibernateTemplate().execute(new HibernateCallback(){ rMVcoO@3
publicObject doInHibernate ^O<v'\!z-
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(Session session)throws HibernateException { 02J(*_o
Criteria criteria = B#hvw'}
[(a3ljbRX
detachedCriteria.getExecutableCriteria(session); 0t7)x8c
return RSj8T<
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criteria.setProjection(Projections.rowCount 8pf]M&
x] `F#5j
()).uniqueResult(); E$z- |-{>
} A",}Ikh='`
}, true); #-Mr3
return count.intValue(); lO|LvJyx
} H!0m8LCnb
} 0827z
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用户在web层构造查询条件detachedCriteria,和可选的 8mmnnf{P
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .7
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PaginationSupport的实例ps。 2gklGDJD
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ps.getItems()得到已分页好的结果集 XPf{R619
ps.getIndexes()得到分页索引的数组 _1Rw~}O
ps.getTotalCount()得到总结果数 ,]ySBAO
ps.getStartIndex()当前分页索引 K_ymA,&()
ps.getNextIndex()下一页索引 ^HR8.9^[1u
ps.getPreviousIndex()上一页索引 Wtw,YFT
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @=AQr4&
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 At<MY`ka
'OTZ&;7{
一下代码重构了。 ^Os }sJ*5S
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我把原本我的做法也提供出来供大家讨论吧: 4Zu1G#(zP
@i(9k
首先,为了实现分页查询,我封装了一个Page类: 451.VI}MR
java代码: 3O4lGe#u
XZ8rM4
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/*Created on 2005-4-14*/
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package org.flyware.util.page; o~y{9Q
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/** WvF{`N
* @author Joa ;*zLf 9i
* ipMSMk7gx
*/ EpR n,[
publicclass Page { QPLWRZu@
hR0a5
/** imply if the page has previous page */ KI#v<4C$P
privateboolean hasPrePage; >Q(\vl@N=
#6#n4`%ER
/** imply if the page has next page */ R!/JZ@au<
privateboolean hasNextPage; C[%&;\3S@
S9$,.aq
/** the number of every page */ t {1 [Ip
privateint everyPage; Wz R)R9x]
\hI?XnL#
/** the total page number */ >oyf i:
privateint totalPage; uUHWTyoO
EI?8/c
/** the number of current page */ DFZ@q=ZT
privateint currentPage;
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/** the begin index of the records by the current z<!A;.iD
bp?TO]LH
query */ D5Sbs(
privateint beginIndex; uMGy-c
W[`ybGR<
{W{;VJKQ2
/** The default constructor */ [cEGkz
public Page(){ ,Js_d
S/pU|zV[
} &-^*D%9
@VOegf+N
/** construct the page by everyPage ^J^~5q8
* @param everyPage WwnBe"7M
* */ *]<= 04v]R
public Page(int everyPage){ YZOwr72VL
this.everyPage = everyPage; =Oh$pZRymu
} +&f_k@+
,Iz9!i
J"
/** The whole constructor */ tGl|/
public Page(boolean hasPrePage, boolean hasNextPage, v_%6Ly
{U3jJ#K
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int everyPage, int totalPage, 3HP
{
a
int currentPage, int beginIndex){ nSSJl
this.hasPrePage = hasPrePage; zCA8}](C^
this.hasNextPage = hasNextPage; <=%[.. (S
this.everyPage = everyPage; )q4nyT>M
this.totalPage = totalPage; [D+PDR
this.currentPage = currentPage; _O87[F1
this.beginIndex = beginIndex; B3[X{n$px
} #<&@-D8
pcscNUp
/** 'CqAjlj
* @return =M@)qy
* Returns the beginIndex. 9dszn^]T
*/ n@bkZ/G
publicint getBeginIndex(){ ]!P6Z?
return beginIndex; }>y~P~`S:
} 6z~ [Ay
ny^uNIRPR
/** ]CS
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* @param beginIndex (qc<'$o
* The beginIndex to set. fWfhs}_
*/ k8}'@w
publicvoid setBeginIndex(int beginIndex){ $`0^E#Nl
this.beginIndex = beginIndex; +YCWoX2
} [.$%ti*!
{#z47Rz
/** |yOIC,5[JW
* @return g .:ZMV
* Returns the currentPage. @c8RlW/A
*/ <$uDN].T4
publicint getCurrentPage(){ l&] %APL
return currentPage; >c:nr&yP
} *}(B"FSO
9
s2z=^
/** ~k
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* @param currentPage X&49C:jN
* The currentPage to set. @{<^rLt
*/ 5 8U[IGs(
publicvoid setCurrentPage(int currentPage){ Z$Qwn
this.currentPage = currentPage; (l2n%LL]*
} \:n<&<aVSr
8r,0Qic2K
/** OaN"6Ge#
* @return 0_^3
|n
* Returns the everyPage. 6+>X`k%D
*/ ?5pZp~
publicint getEveryPage(){ Pa|*Jcr
return everyPage; B~<bc
} 4|eI_u{_
]wbV1Y"
/** !14v Ovj4{
* @param everyPage vHPsHy7y
* The everyPage to set. $Zrc-tkV
*/ q8e] {sT'!
publicvoid setEveryPage(int everyPage){ sFgsEKs
this.everyPage = everyPage; fE>JoQs38
} 6k37RpgH
j{ri]?p
/** e<u~v0rDl
* @return Fb{HiU9<!
* Returns the hasNextPage. YZ->ep}
*/ raP9rEs
publicboolean getHasNextPage(){ FPE6H:'
return hasNextPage; #xq|/JWs
} YcSPU(
`RE
K,^U
/** q(#,X~0
* @param hasNextPage u~N'UD1x
* The hasNextPage to set. #K>Ue>hx
*/ 8)f/H&)>8
publicvoid setHasNextPage(boolean hasNextPage){ T+5H2]yy)
this.hasNextPage = hasNextPage; !i{5mc\
} K1-3!G
|gGD3H
/** d=HD!
e
* @return 0SZ:C(]
* Returns the hasPrePage. /5f=a
*/ _#<7s`i
publicboolean getHasPrePage(){ 9.Sv"=5gz
return hasPrePage; !,DA`Yt
} |L
<
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/** mP
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* @param hasPrePage kh"APxQ79
* The hasPrePage to set. A(JgAV1{
*/ !3*%-8bp
publicvoid setHasPrePage(boolean hasPrePage){ v@:m8Y(t
this.hasPrePage = hasPrePage; .7Itbp6=R
} 5%fR9?)
[5P1 pkZ
/** '81WogH:
* @return Returns the totalPage. OL@' 1$/A
* #4& <d.aw'
*/ 1(a+|
publicint getTotalPage(){ 6#2E {uy;R
return totalPage; d]^\qeG^p
} iB{l:
Ke\FzZ]
/** >% E=l
* @param totalPage 4m_CPe
* The totalPage to set. ru*}lDJ
*/ g+ cH
publicvoid setTotalPage(int totalPage){ e[.JS6
this.totalPage = totalPage; t,yMO
} CN#2-[T
'&iAPc4=
} D^H4]7wG@
t[bZg9;
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g;</ |Z
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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 24d{ol)
]Cc8[ZC
个PageUtil,负责对Page对象进行构造: m)xz_Plc
java代码: Vs&Ul6@N
PWN$x`h g[
R"{oj]d;$F
/*Created on 2005-4-14*/ RjG=RfB'V
package org.flyware.util.page; ZTi KU)
x`zE#sD
import org.apache.commons.logging.Log; x@,B))WlGr
import org.apache.commons.logging.LogFactory; [kPF J f
.^!uazPE0
/** h[j(@P
* @author Joa |6zx
YuX
* 1H7bPl|
*/ Q~$hx{foN
publicclass PageUtil { N/eFwv.Er
@"BkLF
privatestaticfinal Log logger = LogFactory.getLog 4[f>kY%[
JCZ 5q9b
(PageUtil.class); IM&l%6[).
vo]$[Cp|4
/** eih~ SBSH
* Use the origin page to create a new page Q`[J3-Q*{
* @param page &s_)|K
* @param totalRecords Nmu=p~f}3`
* @return s%S; 9T
*/ Uk= L?t
publicstatic Page createPage(Page page, int [5s4Jp$+
XiN@$
totalRecords){ ev%}\^Vl[
return createPage(page.getEveryPage(), 6Bn%7ZBv
Tq!.M1{&
page.getCurrentPage(), totalRecords); s_Gf7uC
} jL9to6 Hmr
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/** ~ YCZvJ
* the basic page utils not including exception o_&*?k*
XXZ <r
handler lc\f6J>HT
* @param everyPage nM6/c
* @param currentPage \tZZn~ex
* @param totalRecords E|hW{ oX3
* @return page ""u>5f
*/ Y8%*S%yO
publicstatic Page createPage(int everyPage, int vHxLn/
bf-V Q7
currentPage, int totalRecords){ i[a1ij=
everyPage = getEveryPage(everyPage); CxJkT2
currentPage = getCurrentPage(currentPage); EZg$mp1
int beginIndex = getBeginIndex(everyPage, b0!ZA/YC-
Jx4"~ 4
currentPage); ;`-@L
int totalPage = getTotalPage(everyPage, k<!xOg
-@yu 9=DT
totalRecords); AWn$od`#s
boolean hasNextPage = hasNextPage(currentPage, 4]%v%64U
},(Ln%M
totalPage); ~xV|<;
boolean hasPrePage = hasPrePage(currentPage); Ym/y2B(
= s$UU15
returnnew Page(hasPrePage, hasNextPage, Z^SF $+UN
everyPage, totalPage, [nG@
3n
currentPage, 0dKi25J
R`!'c(V
beginIndex); "`8~qZ7k
} ]9/{
15tT%TC
privatestaticint getEveryPage(int everyPage){ $g+q;Y~i0
return everyPage == 0 ? 10 : everyPage; qJf=f3
} /5 6sPl
7}
>pq= .)X}
privatestaticint getCurrentPage(int currentPage){ $ @Fvl-lK
return currentPage == 0 ? 1 : currentPage; %$H~
} ~AbTbQ3
'SE?IE {
privatestaticint getBeginIndex(int everyPage, int }Gg:y?
GtSvb6UNn
currentPage){ >xJh!w<pB
return(currentPage - 1) * everyPage; ohj(1jt
} l&4+v.zr
pX v@QD#!
privatestaticint getTotalPage(int everyPage, int WyDL ah^/
+ U];
totalRecords){ 9 9S-P}xd
int totalPage = 0; VwxLElV
Eggdj+
if(totalRecords % everyPage == 0) /WWD;keP5
totalPage = totalRecords / everyPage; :Mq-4U.e
else q=(.N>%
totalPage = totalRecords / everyPage + 1 ; Y] "_}
ZAcH`r*
return totalPage; #Kd^t=k
} &]mZp&
re;^,
privatestaticboolean hasPrePage(int currentPage){ HHU0Nku@ho
return currentPage == 1 ? false : true; Q1?09
} sGdlS&08(
Az"(I>VfD
privatestaticboolean hasNextPage(int currentPage, g<&n V>wF
GN%|'eU
int totalPage){ \vQjTM-7
return currentPage == totalPage || totalPage == 4OOH
3O
="*:H)
0 ? false : true; N akSIGm
} fXJbC+
[TFd|ywn
7(oX1hN
} vOKWi:-U
quEP"
G^Q8B^Lg
C_~hX G
X|iWnz+^
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 V<%eWT)x7C
9;*-y$@
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 ~$\9T.tre2
Fw!TTH6l0
做法如下: 6*]g~)7`Q~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 q;<=MO/
m5/d=k0l
的信息,和一个结果集List: B"rfR_B2M#
java代码: ?=\&O=_ln
wxx3']:
_'"whZ)2
/*Created on 2005-6-13*/ zj9)vr`7
package com.adt.bo; /\0rRT
WK<:(vu.
import java.util.List; Bl"BmUn
=KctAR;
import org.flyware.util.page.Page; 5RysN=czA
<@puWm[p
/** QxaW
x
* @author Joa g} /efE
*/ V{yP/X
publicclass Result { /P>t3E2c
ZgP~VB0)$
private Page page; 1'G&PX
n8dJ6"L<"
private List content; >ARZ=x[
+KzbaBK
/** ` ,O#r0m
* The default constructor c6@7>PM
*/ %gb4(~E+N
public Result(){ 1K`7
super(); C=6.~&(
} X*^^W_LH.
$k|:V&6SV
/** :p@.aD5
* The constructor using fields &Oih#I
* VoTnm
* @param page bz1+AJG
* @param content kU
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*/ 5@kNvi
public Result(Page page, List content){ oXxY$x*R1
this.page = page; \[57Dmo
this.content = content; ,R~{$QUl
} k)t_U3i
7l~d_<h
/** J:!m49fF
* @return Returns the content. p!OCF]r
*/ abW[hp
publicList getContent(){ ruKm_j#J
return content; +=:*[JEK,U
} pp2,d`01[L
RiPxz=kr
/** !)1gGXRY
* @return Returns the page. M:9
6QM~
*/ {%"n[DLps
public Page getPage(){ $q
iY)RE
return page; pr) `7VuKp
} !G8=S'~~
!pqfx93R*
/** XDt MFig
* @param content 1[g -f,
* The content to set. ZgzjRa++
*/ I+VL~'VlS
public void setContent(List content){ BIk0n;Kz<L
this.content = content; xRI7_8Jpyn
} 8?za&v
RZgklEU
/** LrGLIt`
* @param page =sYUzYm
* The page to set. sT*D]J
2
*/ :"~SKJm
publicvoid setPage(Page page){ S /kM#
this.page = page; 4*D'zJsJ
} r+D ?_Lk
} OtVRhR3>
]2 7
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2:6W_[7l!
<y}9Twdy
2. 编写业务逻辑接口,并实现它(UserManager, l
10p'9n
J_|LGrt})
UserManagerImpl) F+m%PVW:
java代码: 2YbI."ob
0|J]EsPxu
"?X,);5S
/*Created on 2005-7-15*/ A5\00O~
package com.adt.service; X9-WU\?UC
nqFJNK]a
import net.sf.hibernate.HibernateException; ){I0
7'~Oai~r
import org.flyware.util.page.Page; ;J>upI
-91*VBrOd
import com.adt.bo.Result; yd|ro G/
Km)VOX[ZZ
/**
L* 0$x
* @author Joa a7fFp9l!
*/ @,:6wKMc
publicinterface UserManager { \`:nmFO(9
AbExJ~JV\g
public Result listUser(Page page)throws F4*ssx
4x)etH^o
HibernateException; 1o8C4?T&
Ov-Y.+L:
} Hh1]\4D,4
F<+!28&h
[X%Wg:K
Z^[
]s1iP}
Img$D*BM
java代码:
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0z
=?}xr
l"rX'g?
/*Created on 2005-7-15*/ :u9OD` D
package com.adt.service.impl; ~z kzuh
#
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import java.util.List; yp!7^
A/c #2
import net.sf.hibernate.HibernateException; k6$Ft.0d1Z
RD|DHio%
import org.flyware.util.page.Page; {44#<A<
import org.flyware.util.page.PageUtil; N;q)[Dr
B{lj.S`mB
import com.adt.bo.Result; Bc*FH>E
import com.adt.dao.UserDAO; &|K9qa~)Y
import com.adt.exception.ObjectNotFoundException; `6:B0-r
import com.adt.service.UserManager; qI%X/'
Z_h-5VU-
/** j2RdBoCt
* @author Joa 0sA+5*mdM
*/ KSAE!+
publicclass UserManagerImpl implements UserManager { ;I/ A8<C
i,B<k 0W9
private UserDAO userDAO; dJjkH6%}
M-8`zA2
/** KjNA PfL
* @param userDAO The userDAO to set. @Cml^v@`L
*/ L"tzUYxg
publicvoid setUserDAO(UserDAO userDAO){ zMXQfR
this.userDAO = userDAO; |[Rlg`TQ;*
} % aqP{mOO
&"?S0S>r!
/* (non-Javadoc) ^)UX#D3b
* @see com.adt.service.UserManager#listUser H:F'5Zt
%6W%-`
(org.flyware.util.page.Page) {[)n<.n[g
*/ vB%os Qm
public Result listUser(Page page)throws +,1 Ea )
n'@*RvI:
HibernateException, ObjectNotFoundException { >/4N :=.h
int totalRecords = userDAO.getUserCount(); =z!^OT6eb
if(totalRecords == 0) .>a
[
throw new ObjectNotFoundException {SkE`u4Sz
f#kT?!sP
("userNotExist"); !<3!ORFO
page = PageUtil.createPage(page, totalRecords); 0Lf4^9N
List users = userDAO.getUserByPage(page); RKPX*(i~
returnnew Result(page, users); pft-.1py
} t$e' [;w
WDi2m"
} +ag_ w}
!(HPx@_
bE;c&g
)|=4H>?%
ek"Uq RY
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zP&D
tv_&PIu]L
询,接下来编写UserDAO的代码: bXi!_'z$
3. UserDAO 和 UserDAOImpl: s o1hC
java代码: [w90gp1O[
FeZ*c~q
Za,myuI+
/*Created on 2005-7-15*/ \ZA@r|=$
package com.adt.dao; L54]l^ls>
61w
({F
import java.util.List; ob;O,&e0>
\U3v5|Q
import org.flyware.util.page.Page; ?<` ;lu/eL
[MuZ^'dR
import net.sf.hibernate.HibernateException; ?t5<S]'r$
UqD ]@s`
/** /i~x.i3
* @author Joa zI0d
*/ S Rk%BJ? ~
publicinterface UserDAO extends BaseDAO { Ci4;e
,{; *b
v
publicList getUserByName(String name)throws guG&3{&\s
TuEM
HibernateException; WvZt~x&2
Z9.0#Jnu
publicint getUserCount()throws HibernateException; :(\JY?+w
?N(<w?Gat
publicList getUserByPage(Page page)throws ^
L]e]<h(
/J(vqYK"
HibernateException; wn;)La
2M*i'K;;)P
} 58d[>0Xa[g
\wDL oR
r1TdjnP,2^
fTso[r:F.
Gr 4v&Mz:
java代码: o*Xfgc
9Z2 1|5
JA*+F1s
/*Created on 2005-7-15*/ 0'HQ=pP
package com.adt.dao.impl; ah%Ws#&
<D P8a<{{
import java.util.List; $
x:N/mMu`
`8S3Y
import org.flyware.util.page.Page; YS#*#!ZMn?
)Gm9x]SVl
import net.sf.hibernate.HibernateException; BA2J dU
import net.sf.hibernate.Query; +4
h!;i
i)'tt9f$
import com.adt.dao.UserDAO; p="0Y<2l
J?dLI_{<
/** !Sw=ns7
* @author Joa OIJT~Z}
*/ v$D U
q+
public class UserDAOImpl extends BaseDAOHibernateImpl x5CMP%}d
?%[~J
implements UserDAO { r
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{
"X^<g{]
/* (non-Javadoc) fZj,Q#}D
* @see com.adt.dao.UserDAO#getUserByName S43JaSw)
O,9^R
(java.lang.String) J&s$Wqf
*/ ^vPsp?
publicList getUserByName(String name)throws d]Y;rqjue
MI'"Xzp{s
HibernateException { 4=o vm[
String querySentence = "FROM user in class ,zdGY]$
i!RfUod
com.adt.po.User WHERE user.name=:name"; lm
96:S
Query query = getSession().createQuery =@0J:"c
YVwpqOE.=
(querySentence); Xl<iR]lda
query.setParameter("name", name); |iI
dm
return query.list(); Av?R6
} <zL_6Y2
3LT~-SvL
/* (non-Javadoc) w|6/ i/X
* @see com.adt.dao.UserDAO#getUserCount()
q"
f65d4c
*/ lcm3wJ'w
publicint getUserCount()throws HibernateException { E*u*LMm
int count = 0; BvsSrse
String querySentence = "SELECT count(*) FROM oOaFA+0x
|?#JCG
user in class com.adt.po.User"; A[8m3L#k
Query query = getSession().createQuery E]rXp~AZm
u5Vgi0}A
(querySentence); TIxOMY y
count = ((Integer)query.iterate().next I`_I^C3
Y X^c}t}U
()).intValue(); [8a(4]4
return count; e.skE>&
} |$b8(g$s)
'.1P\>x!]
/* (non-Javadoc) .whi0~i
* @see com.adt.dao.UserDAO#getUserByPage '9Z`y_~)G
cZQ8[I
(org.flyware.util.page.Page) W~0rSVD$<z
*/ K^U="
publicList getUserByPage(Page page)throws o0]YDX@T
nj'5iiV`]
HibernateException { 5XUm} D$
String querySentence = "FROM user in class Ga5*tWj
xy]O8>b
com.adt.po.User"; ~t~[@2?WG
Query query = getSession().createQuery %+=;4tHJ
-R]0cefC<f
(querySentence); Bd <0}
query.setFirstResult(page.getBeginIndex()) P*A+k"DU1
.setMaxResults(page.getEveryPage()); Yu\$Y0 {]
return query.list(); N?ccG\t
} YD'gyP4
XQ]vJQYIR
} Q $}#&
\0x>#ygX
} Xo#/9
["<Xh0_
{#qUZ z-
至此,一个完整的分页程序完成。前台的只需要调用 zPa2fS8
~c35Y9-5
userManager.listUser(page)即可得到一个Page对象和结果集对象 JI[8n$pr]
8&G9 ?n`I5
的综合体,而传入的参数page对象则可以由前台传入,如果用 9L:wfg}8s
'EiCTl
webwork,甚至可以直接在配置文件中指定。 L@{'J
s|e.mZk/
下面给出一个webwork调用示例: ud r\\5
java代码: Yi%lWbr
(|K+1R
<Z:FY|'s
/*Created on 2005-6-17*/ B=TUZ)
package com.adt.action.user; oI{.{]
hK3-j;eg
import java.util.List; 5[jcw`
B18BwY
import org.apache.commons.logging.Log; P|<V0
Vs.
import org.apache.commons.logging.LogFactory; Y2x|6{ #
import org.flyware.util.page.Page; Gu*y7I8
2L~Vr4eHG
import com.adt.bo.Result; {6v.(Zlh$
import com.adt.service.UserService; TQT3]h6
import com.opensymphony.xwork.Action; bO\++zOF
^x\VMd3*w
/** P+o"]/7U
* @author Joa G0UaE1n
*/ {P8d^=#q
publicclass ListUser implementsAction{ 4{YA['
lH4Nbluc^
privatestaticfinal Log logger = LogFactory.getLog x(TF4W=j
ks0Q+YW
(ListUser.class); ?Fl}@EA#M
n?fy@R
private UserService userService; R%WY!I8C
fWmc$r5n](
private Page page; ,2fi`9=\
]ZcivnN#
privateList users; o~~;I
}QCnN2bV
/* @&}}tALi
* (non-Javadoc) 09-8Xzz
* ]zol?
* @see com.opensymphony.xwork.Action#execute() 9r].rzf9
*/ R'k`0
publicString execute()throwsException{ >J7slDRo
Result result = userService.listUser(page); FMVAXOO
page = result.getPage(); lV$JCNe
users = result.getContent(); LS[o7 !T(
return SUCCESS; \#HW.5
} JD$g%hcVZa
YGo?%.X
/** 4u:SE
* @return Returns the page. }gkLO
TJ/,
*/ tn5%zJ#+
public Page getPage(){ $xWwI(SaB
return page; eL}w{Hlk
T
} CT[9=wV)m%
sG`x |%t
/** Kyh>O)"G^%
* @return Returns the users. ]bY|>q
*/ e'K~WNT
publicList getUsers(){ efXnF*Z
return users; j;3I` :
} )q=F_:$
_eKO:Y[e
/** pN[WYM?[
* @param page vha9,5_
* The page to set. xsH1)
*/ M@cFcykK
publicvoid setPage(Page page){ |T|m5V'l
this.page = page; ;bE/(nz M
} Z A(u"T~
Z~J]I|R:
/** s * (a
* @param users 6$R9Y.s>Z
* The users to set. =-2~>B
*/ <,M"kF:
publicvoid setUsers(List users){ M`cxxDj&j
this.users = users; g$K\rA
} 5s[nE\oaG
J# (AX6
/** v&d1ACctJ
* @param userService 5%I3eL%s
* The userService to set. 1"H;Tr|
*/ .?45:Ey~g
publicvoid setUserService(UserService userService){ l8oaDL\f
this.userService = userService; [Z$H<m{c-
} B7 s{yb
} WQ9e~D"
fQfn7FaW_\
(.4lsKN<
(DiduSJ
?@'&<o0p#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, aD: #AmbJ
RCWmdR#}V
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那
RNk|h
>jI.$%L$
么只需要: |n26[=\B
java代码: VRd7H.f,A6
sSW'SE?,<
17s~mqy
<?xml version="1.0"?> '`2KLO>!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork %>m.Z#R(
AQ'%}(#0
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I){4MoH.
;xwcK-A
1.0.dtd"> $XF$ n#ua
PT~htG<Fw
<xwork> pkn^K+<n,
HA,o2jZ?In
<package name="user" extends="webwork- ~XOmxz0
v #+ECx
interceptors"> tAv3+
I\mF dE
<!-- The default interceptor stack name QC+
Z6WS;
&r1(1<
--> ,CqWm9
<default-interceptor-ref cw<IL
*z~,|DQ(A
name="myDefaultWebStack"/> Cab.a)o
\BnU?z
<action name="listUser" :c/54Ss~
uBlPwb,V
class="com.adt.action.user.ListUser">
(Q8!5s
<param G8av5zR
2{=]Pf
name="page.everyPage">10</param> ]E/0iM5
<result =%W:N|k
&aRL}#U
name="success">/user/user_list.jsp</result> ,:t,$A
</action> vJ&_-CX
4}H+hk8-
</package> 8US#SI'x
GLf!i1Z
</xwork> r9ulTv}X
Dj\nsc@e3
_WEJ,0*#'
Vm%G
q
~F,~^r!Jtu
aKj|gwo!
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 b? );
D
]RT
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 F vkyp"W3
S`kOtZ_N n
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 U`(=iyWP=
/QQRy_Z1)
0+CcNY9
7"(Zpu
`>sOOA
我写的一个用于分页的类,用了泛型了,hoho D{+@ ,C7B
a3yNd
java代码: 1/97_:M0~F
vD#U+
.y
s_'F-]0
package com.intokr.util; ozRO:*51
~[Tcl
import java.util.List; r
XJx~
g
_KM?
?&
/** }B-$}
* 用于分页的类<br> P*&[9)d6
* 可以用于传递查询的结果也可以用于传送查询的参数<br> uyYV_Q0~;
* bWo
* @version 0.01 Q4cCg7|0
* @author cheng Eg)24C R 4
*/ (%B{=w}8
public class Paginator<E> { `H! (hMMV
privateint count = 0; // 总记录数 ?,pwYT0g
privateint p = 1; // 页编号 q=X<QhK
privateint num = 20; // 每页的记录数 Al^tM0T^
privateList<E> results = null; // 结果 A$@;Q5/2
JK!(\Ae.
/** !)]/?&uo
* 结果总数 n#P>E(K
*/
9)VAEyv
publicint getCount(){ 3RtVFDIZA"
return count; pq)
=
} E*YmHJ:k
.b";7}9{
publicvoid setCount(int count){ %tVU Rj
this.count = count; HgY@M
} 3=
=["hO
0S5xmEzop
/** ZH
Q?{"
* 本结果所在的页码,从1开始 <W0(!<U
* E>_Rsw *
* @return Returns the pageNo. -9dZT
*/ |XB<vj07G
publicint getP(){ d#T5=5#
return p; J&aN6 l?
} @}q, ';H7
qArR5OJ
/** %NkiY iA
* if(p<=0) p=1 p6j-8ggL
* :<aGZ\R5
* @param p %G!!0V!
*/ &oG>Rqkm
publicvoid setP(int p){ WXxnOLJr
if(p <= 0) +t,b/K(?]
p = 1; Tt~4'{Bc
this.p = p; M]o]D;N~l
} FsqH:I4O
b]u=Iza
/** OmBM)g
* 每页记录数量 o`CM15d*7o
*/ 9fX0?POG
publicint getNum(){ x;W!sO@$
return num; 4S42h_9
} ?eTZ>o.p/
uRy}HLZ"
/** HW[&q
* if(num<1) num=1 +^9^)Ur|
*/ )L&y@dy)
publicvoid setNum(int num){ vEx'~_+a9
if(num < 1) BZ\="N#f
num = 1; xtGit}
this.num = num; \8#[AD*@s2
} \Hb!<mrp
?J$k
5;
/** 46vC/
* 获得总页数 ~Y43`@3H:
*/ EC\@$Fg
publicint getPageNum(){ E0qJ.v
return(count - 1) / num + 1; 3sV$#l P
} tzN9d~JZ
ds*gL ~k^
/** 1R_@C.I
* 获得本页的开始编号,为 (p-1)*num+1 w&IYCYK_
*/ X#T|.mCdC
publicint getStart(){ #c:@oe4v
return(p - 1) * num + 1; =H7p&DhD