Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #u^d3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0jH2.d=
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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 jT',+
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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 >{Q2S
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分页支持类: iDr0_y*t
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java代码: AsOI`@FV
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package com.javaeye.common.util; gO%3~f!vY#
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import java.util.List; T28#?Lp6]
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publicclass PaginationSupport { FU zY&@Y
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publicfinalstaticint PAGESIZE = 30; #%~wuCn<K
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privateint pageSize = PAGESIZE; XQ>m8K?\d
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privateList items; f|!zjX`
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privateint totalCount; ~7|z 2L
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privateint[] indexes = newint[0]; qmhHHFjQ
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privateint startIndex = 0; 3~ylBJJ
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public PaginationSupport(List items, int Q =Z-vTD+
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totalCount){ idHBz*3~ps
setPageSize(PAGESIZE); gwyz)CUkL
setTotalCount(totalCount); zrcSPh
setItems(items); *5^h>Vk/
setStartIndex(0); NeYj[Q~xy
} 5^qI6
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public PaginationSupport(List items, int rRxqV?>n!
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totalCount, int startIndex){ Xh5
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setPageSize(PAGESIZE); k7? (IU
setTotalCount(totalCount); @<_4Nb
setItems(items); qSON3Iid
setStartIndex(startIndex); ~e|~c<!z8@
} Hly$ Wm
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public PaginationSupport(List items, int _|3n h;-m
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totalCount, int pageSize, int startIndex){ ^XV$J-
setPageSize(pageSize); mAz':R[
setTotalCount(totalCount); $%LjIeVA5
setItems(items); Y>r9"X|&H
setStartIndex(startIndex); #8cY,%<S]
} Ef69]{E
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publicList getItems(){ .- {B
return items; {A{=RPL
} }{s<!b
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publicvoid setItems(List items){ {/N4/gu
this.items = items; &q>=6sQvf
} dF"Sz4DY#
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publicint getPageSize(){ $5l 8V
return pageSize; ht` !@B
} sa{X.}i%E
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publicvoid setPageSize(int pageSize){ p "u5wJ_
this.pageSize = pageSize;
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} d
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publicint getTotalCount(){ qlO(z5Ak
return totalCount; p \1-.
} &jr'vS[b
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publicvoid setTotalCount(int totalCount){ t0(1qFi
if(totalCount > 0){ a~=$9+?w
this.totalCount = totalCount; 6p])2]N>p
int count = totalCount / I8rtta
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pageSize; +Ccj@#M;
if(totalCount % pageSize > 0) %Sf%XNtu
count++; $5Jo%K%
indexes = newint[count]; :A.dlesv6
for(int i = 0; i < count; i++){ \hoYQK j
indexes = pageSize * hKj"Lb9]
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i; g4^=Q'j-
} |hk?'WGc`0
}else{ \L Gj]mb1
this.totalCount = 0; XDRw![H,~
} 6SJ
} =J:6p-\*
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publicint[] getIndexes(){ WW\t<O;z
return indexes; &;I=*B~kE$
} ckG`^<
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publicvoid setIndexes(int[] indexes){ >VIb|YA
this.indexes = indexes; lky{<jZ%
} {]ie|>'=C
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publicint getStartIndex(){ v0v%+F#>@
return startIndex; lB3@jF
} %iMRJ}8(7
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publicvoid setStartIndex(int startIndex){ 0<(F
8
if(totalCount <= 0) V 3?x_pp
this.startIndex = 0; g?-HAk6
elseif(startIndex >= totalCount) T$)N2]FE
this.startIndex = indexes %\<SSp^n
F-0 |&0
[indexes.length - 1]; +a7J;-|
elseif(startIndex < 0) !0p_s;uu,W
this.startIndex = 0; AT$eTZ]M
else{ A"ApWJ3
this.startIndex = indexes fg}&=r
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[startIndex / pageSize]; R{N9'2l:
} _ljdo`j#N
} nZ7FG
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publicint getNextIndex(){ wd86 y
int nextIndex = getStartIndex() + /-J12 O
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pageSize; :s(vn Ie^
if(nextIndex >= totalCount) 1FC' iGI
return getStartIndex(); 1j4(/A
else 1T96W :
return nextIndex; ~m@v ~=
} dB`3"aSN7
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publicint getPreviousIndex(){ wX7|a/|@
int previousIndex = getStartIndex() - c:>&iB-Yu
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pageSize; xweV8k/
if(previousIndex < 0) YI0ubB
return0; 3"9'MDKH
else GP|G[
return previousIndex; ur*@TIvD
} (`nn\)
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} B{`4"uEb$G
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抽象业务类 8~q%H1[I\N
java代码: ;ndsq[k>
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/** cU`sA_f
* Created on 2005-7-12 n+Bh-a V
*/ fYv= yP~
package com.javaeye.common.business; gt~hUwL
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import java.io.Serializable; 4|PNsHXt
import java.util.List; \*24NB
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import org.hibernate.Criteria; 7J:zIC$u>
import org.hibernate.HibernateException; @#wBK3Ut^
import org.hibernate.Session; Tno[LP,
import org.hibernate.criterion.DetachedCriteria; kaK0'l2%
import org.hibernate.criterion.Projections; G?`x$U U
import ]gxt+'iAFS
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org.springframework.orm.hibernate3.HibernateCallback; ?$:;hGO.<~
import 7F=Xn@ _
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org.springframework.orm.hibernate3.support.HibernateDaoS :
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upport; !sbKJ+V7
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import com.javaeye.common.util.PaginationSupport; >=<qAkk
'%k<? *
public abstract class AbstractManager extends ,VtrQb)Yf
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HibernateDaoSupport { jSY&P/[xb
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privateboolean cacheQueries = false; aahAUhF
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privateString queryCacheRegion; gc%aaYf>
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publicvoid setCacheQueries(boolean g\Gx
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cacheQueries){ a-P'h1hbH
this.cacheQueries = cacheQueries; "ZuhN(-`
} {|{}]B
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publicvoid setQueryCacheRegion(String ]{`
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queryCacheRegion){ 8UAbTqB-
this.queryCacheRegion = ulc m
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queryCacheRegion; co
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} ]6PX4oK_t
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publicvoid save(finalObject entity){ UIpW#t
getHibernateTemplate().save(entity); je9eJUKE
} q?Jd.r5*
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publicvoid persist(finalObject entity){ 2(s+?n.N
getHibernateTemplate().save(entity); IV"OzQONx
} ^>?E1J3u
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publicvoid update(finalObject entity){ /U|>
getHibernateTemplate().update(entity); a{?`yO/ 2
} mY}_9rTn|
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publicvoid delete(finalObject entity){ dMcCSwYh
getHibernateTemplate().delete(entity); bzI!;P1&
} zvvF9
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publicObject load(finalClass entity, zw13Tu
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finalSerializable id){ \,U#^Vr
return getHibernateTemplate().load f?-=&||f78
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(entity, id); lkj^<%N"r
} Q}a, f75
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publicObject get(finalClass entity, $jLJ&R=?]
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finalSerializable id){ t}Z*2=DO
return getHibernateTemplate().get HwE1cOT
qbrf;`
(entity, id); W YHr'xJ
} WK{{U$:$
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publicList findAll(finalClass entity){ 8 *Fr=+KN
return getHibernateTemplate().find("from ] D(laqS;"
$_2S,3 }
" + entity.getName()); GCw<jHw
} >DHpD?Pm!
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publicList findByNamedQuery(finalString Hk65c0
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namedQuery){ FTB@70
return getHibernateTemplate s_(%1/{
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().findByNamedQuery(namedQuery); W*'gqwM&
} ,zCrix
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publicList findByNamedQuery(finalString query, ;%Z%]nIS
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finalObject parameter){ IIN"'7Z^R
return getHibernateTemplate }v0IzGKs
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().findByNamedQuery(query, parameter); Ek!$Ary
} 2>s@2=Aq
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publicList findByNamedQuery(finalString query, ? WD|a(
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finalObject[] parameters){ UOWOOdWSB
return getHibernateTemplate ;l]OmcL
$(2c0S{ 1
().findByNamedQuery(query, parameters); a '/yN{?p
} 91oIx W
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publicList find(finalString query){ IN? A`A
return getHibernateTemplate().find !ul)e;a
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(query); )N{Qpbh
}
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publicList find(finalString query, finalObject RvL-SI%E
#S[:Q.0 ;
parameter){ w!NtN4>
return getHibernateTemplate().find 3r=IO#
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(query, parameter); Ga\E`J$c
} 5a9PM(
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public PaginationSupport findPageByCriteria ~%Y*2i
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(final DetachedCriteria detachedCriteria){ jWb;Xk4
return findPageByCriteria 0 T!_;IQ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); e_6@oh2s-
} H<dOh5MFh
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public PaginationSupport findPageByCriteria OQ<|XdI$
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(final DetachedCriteria detachedCriteria, finalint UzVnC:
Aa*UV6(v
startIndex){ 6Lw34R
return findPageByCriteria |H&2[B"l
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(detachedCriteria, PaginationSupport.PAGESIZE, [wAI;=.
Bb];qYuCO
startIndex); &?(r#T
} 7O{c>@\
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public PaginationSupport findPageByCriteria RE]u2R6Y
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(final DetachedCriteria detachedCriteria, finalint ![os5H.b#q
@dAc2<4
pageSize, ]zHUF!a*
finalint startIndex){ x72bufd
return(PaginationSupport) oB8u[!
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getHibernateTemplate().execute(new HibernateCallback(){ XW6Ewrm=vT
publicObject doInHibernate heiIb|z
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(Session session)throws HibernateException { ;5 cg<~t
Criteria criteria = 0|8c2{9X,
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detachedCriteria.getExecutableCriteria(session); y5>859"h
int totalCount = 9J_lxy}
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((Integer) criteria.setProjection(Projections.rowCount j{EN %
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()).uniqueResult()).intValue(); j,QeL
criteria.setProjection F!jYkDY
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(null); cYyv
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List items = n=
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criteria.setFirstResult(startIndex).setMaxResults zghUwW |K
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(pageSize).list(); ,g%2-#L%
PaginationSupport ps = 1Qui.],c
}R*[7V9"
new PaginationSupport(items, totalCount, pageSize, oqOv"yLJ:
j?4k{?x
startIndex); &!#,p{}ccU
return ps; ,tv
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} :P<}
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}, true); j K?GB
} x3O$eKy\|5
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public List findAllByCriteria(final =Y>_b
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DetachedCriteria detachedCriteria){ IQxY]0\uf6
return(List) getHibernateTemplate +[Nc";Oy
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().execute(new HibernateCallback(){ Zp]{e6J
publicObject doInHibernate ^yg`U(
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(Session session)throws HibernateException { #r M/
Criteria criteria = i6M_Gk}
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detachedCriteria.getExecutableCriteria(session); OoTMvZP[
return criteria.list(); &S9Sl
} Q9=vgOW+
}, true); 8nw_Jatk1
} 1?sR1du,
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public int getCountByCriteria(final |&lAt\
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DetachedCriteria detachedCriteria){ o^%4w>|
Integer count = (Integer) Q]Q]kj2
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getHibernateTemplate().execute(new HibernateCallback(){ 9{_D"h}}
publicObject doInHibernate 6T0[
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(Session session)throws HibernateException { *#{[9d
Criteria criteria = "mr;!"LA
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detachedCriteria.getExecutableCriteria(session); X'4e)E3*O
return n.P$7%G`2
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criteria.setProjection(Projections.rowCount :[P>e
ox
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()).uniqueResult(); \tE2@
} 8&: *<
}, true); Ag
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return count.intValue(); $$`E@\5P
} ]etLobV
} ;=.VKW%U
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}
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用户在web层构造查询条件detachedCriteria,和可选的 (wLzkV/6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Jx[Z[R O2
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PaginationSupport的实例ps。 @*jd.a`
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ps.getItems()得到已分页好的结果集 'V=w?G
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ps.getIndexes()得到分页索引的数组 C'3/B)u}l
ps.getTotalCount()得到总结果数 }TD$!
ps.getStartIndex()当前分页索引 Un\h[m
ps.getNextIndex()下一页索引 ;(M`Wy]2
ps.getPreviousIndex()上一页索引 &qqS'G*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 e(E6 t_
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 TGx:#x*k
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一下代码重构了。 zMasA
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我把原本我的做法也提供出来供大家讨论吧: l?E7'OEF:
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首先,为了实现分页查询,我封装了一个Page类: `ZL~k
java代码: `h+ia/
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/*Created on 2005-4-14*/ ((L=1]w
package org.flyware.util.page; #:"F-3A0
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/** #xZ7%
* @author Joa `[x`#irD
* T^YdAQeE
*/ *ZP$dQ
publicclass Page { '&4W@lvyz
;~Y0H9`
/** imply if the page has previous page */ 6FuZMasr*
privateboolean hasPrePage; "i/ l'
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/** imply if the page has next page */ mk#xbvvG
privateboolean hasNextPage; ``bIqY
CC,_I>t
/** the number of every page */ Zhb)n
privateint everyPage; W9>q1
t3%[C;@wB
/** the total page number */ %7WQb]y
privateint totalPage; B[k {u#Kp
r(9#kLXg
/** the number of current page */ 9&e=s<6dO
privateint currentPage; w~EBm=v_>
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/** the begin index of the records by the current kGbtZ} W
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query */ 4E[ 9)n+YV
privateint beginIndex; W8hf
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/** The default constructor */ xW92ZuzSH
public Page(){ J+oK:tzt8
9 -7.4!]I
} os/_ObPiX
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/** construct the page by everyPage ]7SX _:'*
* @param everyPage $kPC"!X\
* */ zq ;YE
public Page(int everyPage){ daamP$h9
this.everyPage = everyPage; SymBb}5
} C4vmgl&
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/** The whole constructor */ " sh%8
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public Page(boolean hasPrePage, boolean hasNextPage, I9JiH,+
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int everyPage, int totalPage, Y`$dtg {
int currentPage, int beginIndex){ lP$bxUNt
this.hasPrePage = hasPrePage; >^mNIfdE^=
this.hasNextPage = hasNextPage; ,+`1 /
this.everyPage = everyPage; 3Yu1ZuIR
this.totalPage = totalPage; 6:Eu[PE~w
this.currentPage = currentPage; g5THkxp
this.beginIndex = beginIndex; R+}x#
} p'#
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/** Ln~Z_!
* @return uL`6}0
* Returns the beginIndex. s{IXth6
*/ `U-i{i
publicint getBeginIndex(){ `$V7AqX (
return beginIndex; 879x(JII
} :Bk!YK
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/** bwHl}3
* @param beginIndex 3I|&}+Z6
* The beginIndex to set.
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*/ w QV4[
publicvoid setBeginIndex(int beginIndex){ ^Kvbpi,
this.beginIndex = beginIndex; Y\CR*om!W
} .QwwGm
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/** HH_w!_f
* @return jlhyn0
* Returns the currentPage. 5f.G^A: _X
*/ cQ:Y@f 9
publicint getCurrentPage(){ '
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return currentPage; jt({@;sU[<
} K|"97{*|2
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/** 8H0d4~Wg
* @param currentPage #2N']VP
* The currentPage to set. %}t<,ex(yO
*/ D{b*,F:&@)
publicvoid setCurrentPage(int currentPage){ bnll-G|
this.currentPage = currentPage; IU
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} H@!\?5I
1e Wl:S}
/** J;?#Zt]`L
* @return Ww8C}2g3
* Returns the everyPage. aT v
*/ ?Hb5<,1u3
publicint getEveryPage(){ @-uV6X8|
return everyPage; ^TC<_]7
} +`;YK7o
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/** ]_8bX}_n
* @param everyPage %/b3G*$W
* The everyPage to set. cba
*/ ;<aT|4
publicvoid setEveryPage(int everyPage){ v' x)AbbC
this.everyPage = everyPage; Gp0B^^H$
} ?Cg",k '
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/** 4Dd@&N
* @return p};B*[ki
* Returns the hasNextPage. 'N-nFc^
*/ r8o9C
publicboolean getHasNextPage(){ 5PaOa8=2f
return hasNextPage; MfX1&/Z+
} Bz&6kRPv
~EYsUC#B_
/** f)~j'e
* @param hasNextPage A Th<=1
* The hasNextPage to set. ~OuK ewr\
*/ G5C=p:o{/
publicvoid setHasNextPage(boolean hasNextPage){ wt8?@lJ"/
this.hasNextPage = hasNextPage; 15o<'4|=Lm
} SN${cs%
W @X/Z8.(
/** 9n(.v}
* @return GFq,Ca~
* Returns the hasPrePage. :\]TAQd-
*/ M_<? <>|
publicboolean getHasPrePage(){ V30Om3C
return hasPrePage;
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} `R9}.?7
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/** 0
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* @param hasPrePage anM]khs?
* The hasPrePage to set. +,"O#`sy<
*/ }^ g6Y3\
publicvoid setHasPrePage(boolean hasPrePage){ 6~:eO(pK
l
this.hasPrePage = hasPrePage; Ys+2/>!
} 6k1;62Ntk
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/** )~u<u:N
* @return Returns the totalPage. _m;H$N~I#
* M%U1?^j8
*/ ;ui=7[Us
publicint getTotalPage(){ GKT^rc-YT-
return totalPage; Ct8}jg"
} WbIf)\
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/** \dB)G<_
* @param totalPage bhqV2y*'
* The totalPage to set. AW6 "1(D
*/ _J N$zZ{
publicvoid setTotalPage(int totalPage){ y3^>a5z!x
this.totalPage = totalPage; JBvMe H5
}
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} q'% cVM
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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 HZ_,f"22
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个PageUtil,负责对Page对象进行构造: 40M/Gu:
java代码: DJ]GM|?
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/*Created on 2005-4-14*/ JKJ+RkXf3
package org.flyware.util.page; gf]k@-)
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import org.apache.commons.logging.Log; 5 `Mos
import org.apache.commons.logging.LogFactory; sX,."@[
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/** kX1#+X
* @author Joa KhWt9=9
* =Felo8+
*/ T`Jj$Lue{
publicclass PageUtil { V=+wsc
X1N*}@:/
privatestaticfinal Log logger = LogFactory.getLog (G#QRSXc\
]NRQM8\
(PageUtil.class); wpW3%r;9
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/** Bq# l8u
* Use the origin page to create a new page O"c@x:i
* @param page Zf [#~4
* @param totalRecords j3kcNb
* @return ^5- 8'9 w
*/ K3xs=q]:@
publicstatic Page createPage(Page page, int `{
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totalRecords){ 5m(V(@a3
return createPage(page.getEveryPage(), TQjM3Ri=V
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page.getCurrentPage(), totalRecords); F%s'R 0l
} 5jS8{d0
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/** 8`4Z%;1
* the basic page utils not including exception Y7L1`<SC
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handler =w#sCy
* @param everyPage B+w< 0No
* @param currentPage
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* @param totalRecords qyl9#C(a
* @return page a{deN9Qn
*/ FJYc*l
publicstatic Page createPage(int everyPage, int 'nR'o /!
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currentPage, int totalRecords){ }c1?:8p
everyPage = getEveryPage(everyPage); <dA D-2O+
currentPage = getCurrentPage(currentPage); A@I ( &Z
int beginIndex = getBeginIndex(everyPage, ',g'Tl^E
p~!UE/V
currentPage); FLE2]cL-
int totalPage = getTotalPage(everyPage, m0(]%Kdw
r: :LQ$
totalRecords); =iEQE
boolean hasNextPage = hasNextPage(currentPage, iXJ3B&x
f(r=S Xa*
totalPage); ;xKPa6`E
boolean hasPrePage = hasPrePage(currentPage); =,4iMENm!
wm<`0}
returnnew Page(hasPrePage, hasNextPage, F#S)))#
everyPage, totalPage, ]3/_?n-"`
currentPage, d2!A32m
8qi6>}A
beginIndex); =OUms@xcE
} ys#V_ysb
c<c"n'
privatestaticint getEveryPage(int everyPage){ \F
}s"#
return everyPage == 0 ? 10 : everyPage; |sIr}}
} ~g_]Sskf7
x%WL!Lo
privatestaticint getCurrentPage(int currentPage){ ^G~C#t^
return currentPage == 0 ? 1 : currentPage; )PNeJf|@
} ?;dfA/
tU :,s^E"#
privatestaticint getBeginIndex(int everyPage, int bx5f\)
UDUj
currentPage){ l^$8;$Rq
return(currentPage - 1) * everyPage; *NEA(9
} L,<5l?u
<Z -d5D>
privatestaticint getTotalPage(int everyPage, int #w
*]`5
T
ha%3%O8Z
totalRecords){ D_W,Jmet
int totalPage = 0; LG/6_t}
!|1GraiS
if(totalRecords % everyPage == 0) }z$_=v
totalPage = totalRecords / everyPage; @/w($w"
else wP <)
totalPage = totalRecords / everyPage + 1 ; xMb)4 cw}
_eE hIQ9
return totalPage; # RG/B2
} *_aeK~du.
O$2'$44HX
privatestaticboolean hasPrePage(int currentPage){ QQB\$[M!Z
return currentPage == 1 ? false : true; heAbxs
} ~ e4Pj`?=K
0rjH`H]M
privatestaticboolean hasNextPage(int currentPage, ir-= @@
^F*G
int totalPage){ %pR:.u|
return currentPage == totalPage || totalPage == Wd R ~
qNH=
W?T8.
0 ? false : true; ^D{!!)O
} {5$.:Y
R`_RcHY:
cr&sI=i
} iEtnwSt
?(up!3S'x
"-pQL )f
aMxg6\8
A`Nk gVq5:
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。 r fl-(_3
f:=y)+@1My
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 (.:!_OB0N
Nan@SuKY
做法如下: VdVUYp
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 *kliI]BF]
rYp]RX>
的信息,和一个结果集List: \fHtk _
java代码: AB!P(
)&Bf%1>
"M)kV5v%
/*Created on 2005-6-13*/ LQ7.RK
package com.adt.bo; +zU[rhMk'
ypCarvQT
import java.util.List; }#~DX!Sj
-2{NIF^H
import org.flyware.util.page.Page; <6
LpsM}
~HW}Wik
/** xJQ-k/`
* @author Joa /M}jF*5N
*/ Rh[%UNl
publicclass Result { s/;iZiWK
*Zj2*e{Z9U
private Page page; $jpAnZR- /
rq[+p
private List content; ^
#6Ei9di
0|RFsJ"
/** "sM
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* The default constructor C
EzTErn
*/ l7+[Zn/v *
public Result(){ TA2?Ia;@xV
super(); MJ=(rp=YU9
} lURL;h
;tBc&LJ?
/** B
66-l!xa
* The constructor using fields ^}F @*A;o
* qu}&4_`%:V
* @param page >~nc7j
u
* @param content L.cGt"{
*/ CDNh9`
public Result(Page page, List content){ zKnHo:SV
this.page = page; 'S[&-D%(3
this.content = content; \-Oq/g{j
} +d$l1j
Y[0
/** W=[..d
* @return Returns the content. Y$@?Y/rhR
*/ |uT&M`7\{
publicList getContent(){ I3#h
return content; rA"><pH
} v>4kF _N
f&n6;N
/** p^E}%0#
* @return Returns the page. AP2BND9
*/ 5D~>Ed;
public Page getPage(){ 8,5H^Bi
return page; _olhCLIR-
} cNd;qO0$
]tu:V,q
/** wG,"ZN
* @param content .5t|FJ]`$
* The content to set. W@T_-pTCjK
*/ M_ GN3
public void setContent(List content){ "I7 Sed7
this.content = content; x}c%8dO#J
} _w'N
",pN.<F9O
/** UTThl2=+
* @param page {eQ')f
* The page to set. x'uxSeH$
*/ jgkJF[t`
publicvoid setPage(Page page){ d{gj8
this.page = page; PGj?`y4
} I1TzPe
} ,^>WCG
6{qI
?puZqVu5
2f=7`1RCD
PN +<C7/
2. 编写业务逻辑接口,并实现它(UserManager, =>_k ;x
gk*Md+
UserManagerImpl) )]^xy&:|
java代码: Za&.sg3RG
hZudVBn
4Y=sTXbFt
/*Created on 2005-7-15*/ =,UuQJ,l
package com.adt.service; U'Xw'?Uj
fuwv,[m
import net.sf.hibernate.HibernateException; gA&+<SK(
YTtuR`
import org.flyware.util.page.Page; JLZ[sWP='
E@f2hW2
import com.adt.bo.Result; *>ilT5q
?]d[K>bv
/** f\Fk+)e@
* @author Joa !JkH$~
*/ B;r o(R
publicinterface UserManager { T{L{<+9%
#kuk3}&
public Result listUser(Page page)throws XyS|7#o
vE9M2[TJA
HibernateException; F%}0q&
p
PF]&:&-b
} l9 K 3E<g
<IX)D `mf
}-e
!Gphs`YI
P@u&~RN9f+
java代码: Rilr)$
9O%4x"*PO
~4{E0om@
/*Created on 2005-7-15*/ LGOeBEAMV^
package com.adt.service.impl; &SzLEbU!
5&uS700
import java.util.List; C&\vVNV;9
D-/aS5wM
import net.sf.hibernate.HibernateException; OfR\8hAY
""dX4^gtU
import org.flyware.util.page.Page; d^&F%)AT
import org.flyware.util.page.PageUtil; $S"QyAH~-a
Vs)%*1><
import com.adt.bo.Result; UacGq,
import com.adt.dao.UserDAO; ATeXOe
import com.adt.exception.ObjectNotFoundException; W[dMf!(
import com.adt.service.UserManager; `mI%Se
]wMp`}$b@L
/** 4HG@moYn@
* @author Joa f[@M
*/ j'?^<4i
publicclass UserManagerImpl implements UserManager { F^],p|4f
`%2e?"OOJ
private UserDAO userDAO; rQncW~
S+i .@N.^
/** pvz*(u
* @param userDAO The userDAO to set. yrDWIU(8;6
*/ -V'`;zE6
publicvoid setUserDAO(UserDAO userDAO){ yqg&dq
this.userDAO = userDAO; No\H
QQ
} [ imC21U
,sAN,?eG~
/* (non-Javadoc) [n`SXBi+n
* @see com.adt.service.UserManager#listUser X9:(}=E
V
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(org.flyware.util.page.Page) I<w`+<o(
*/ !n=@(bT*wT
public Result listUser(Page page)throws brQkVt_)EE
A%VBBvk
HibernateException, ObjectNotFoundException { ;x[F4d
int totalRecords = userDAO.getUserCount(); ,RkL|'1l
if(totalRecords == 0) ]~,V(K
throw new ObjectNotFoundException mErXdb|L
"EoC7
1
("userNotExist"); 62BJ;/ ]
page = PageUtil.createPage(page, totalRecords); }OeEv@^
List users = userDAO.getUserByPage(page); hIj[#M&6
returnnew Result(page, users); %j].'
;
} QK5y%bTSA
728}K^7:
} /!o(Y8e>x
-%XvWZvZ
23/!k}G"
vT<q zN
5XNIX)H
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {__Z\D2I
1}E`K#
询,接下来编写UserDAO的代码: x8a?I T.
3. UserDAO 和 UserDAOImpl: HQ%-e5Q
java代码: Z\=].[,w4
Co2* -[R
5zlgmCGow
/*Created on 2005-7-15*/ guC/eSxv
package com.adt.dao; +$ )C KC
B|IQ/g?
import java.util.List; e75k-
(89NK]2x
import org.flyware.util.page.Page; o7feH 6Sh
>4:W:;R
import net.sf.hibernate.HibernateException; _tR%7%3*
U.oxLbJ`
/** (~oUd4
* @author Joa ]fXMp*LvY
*/ 1#AdEd[
publicinterface UserDAO extends BaseDAO { \lK iUy/
Sf}>~z2
publicList getUserByName(String name)throws ;lST@>
d"nz/$
HibernateException; D4yJ:ATO&
e~r%8.Wm
publicint getUserCount()throws HibernateException; Xj^6ZJc
U,C
L*qTF
publicList getUserByPage(Page page)throws d:0RDK-}s
Fzk
HibernateException; oK h#th
wVBY^TE
} eI?<*
b .k
J&c
A~Eu_m
UYH;15s
@<--5HbX
java代码: TH2D ;uv
Wy%q9x]}
(veGztt
/*Created on 2005-7-15*/ m~9Qx`fi`
package com.adt.dao.impl; $}<+~JpGfP
ll{jE
import java.util.List;
ykSn=0
bD<[OerG
import org.flyware.util.page.Page; y3$i?}?A
q{ov62t`
import net.sf.hibernate.HibernateException; W-%oj.BMA
import net.sf.hibernate.Query; B:5(sK
rX6"w31
import com.adt.dao.UserDAO; ^.,pq?_
*52*IRH
/** vpx8GiV
* @author Joa {zBf *x
*/ C$\|eC j
public class UserDAOImpl extends BaseDAOHibernateImpl jcQ{,9
H`l
9g+/^j^>?f
implements UserDAO { VO>A+vx3M
$<2r;'?0D
/* (non-Javadoc) 8Cz_LyL
* @see com.adt.dao.UserDAO#getUserByName HDYr?t~V
*. l,_68
(java.lang.String) $ x
6Rmd{
*/ }6.R.*Imz
publicList getUserByName(String name)throws B;[{7J]
OwV>`BIwns
HibernateException { /HgdTyR)
String querySentence = "FROM user in class kVw5z3]Xg
:Ts"f*
com.adt.po.User WHERE user.name=:name"; 2V_C_5)1
Query query = getSession().createQuery ,xB&{J
NY\q
(querySentence); y.2_5&e/
query.setParameter("name", name); 8I$B^,N
return query.list(); BKfcK>%g
} !Sfy'v.
8s pGDg\g
/* (non-Javadoc) :}TT1@
* @see com.adt.dao.UserDAO#getUserCount() z$oA6qB)
*/ <",4O
publicint getUserCount()throws HibernateException { [ jve
|-v=
int count = 0; s/UIo^m
String querySentence = "SELECT count(*) FROM :
m$cnq~h
sXOGIv
user in class com.adt.po.User"; 6UR.,*f=
Query query = getSession().createQuery X{\>TOk
[t5:4
Iq
(querySentence); S9}P5;u
count = ((Integer)query.iterate().next TAlpy$
|Y|{9Osus
()).intValue(); 23@e?A=C
return count; Bx0^?>
} =\`g<0
w'K\}G~
/* (non-Javadoc) cW;to Q!P
* @see com.adt.dao.UserDAO#getUserByPage x:b0G
!L:!X88
(org.flyware.util.page.Page) D{I^_~-\5
*/ K2>(C$Z
publicList getUserByPage(Page page)throws z"bgtlfb8
% ribxgmd
HibernateException { }legh:/*?O
String querySentence = "FROM user in class 9"1 0:\U
KL,=Z&.<=
com.adt.po.User"; db`xlvrCY
Query query = getSession().createQuery 5_ -YF~
-q|K\>tgU
(querySentence); BusD}9QqB
query.setFirstResult(page.getBeginIndex()) :,%~rR
.setMaxResults(page.getEveryPage()); csz/[*
return query.list(); 6 /gh_'&
} N~_GJw@
)dgXS//Y
} 7)!(0.&
F7gipCc1We
K,bv\j;f
x$d3fsEE
I>o+INb:
至此,一个完整的分页程序完成。前台的只需要调用 T^g2N`w2
>(S4h}^I
userManager.listUser(page)即可得到一个Page对象和结果集对象 v Ic0V
W!8g.r4u+,
的综合体,而传入的参数page对象则可以由前台传入,如果用 }GJIM|7^
$'*@g1vY
webwork,甚至可以直接在配置文件中指定。 iM+K&\{_h
:zdMV6s
下面给出一个webwork调用示例: dqO!p6
java代码: /2pf*\u
e^Q$Tog<
>;kCcfS3ct
/*Created on 2005-6-17*/ *`OgwMr)M
package com.adt.action.user; *#-X0}'s
4V9DPBh
import java.util.List; dOh'9kk3
#7I,.DUy[
import org.apache.commons.logging.Log; X5 UcemO
import org.apache.commons.logging.LogFactory; PhW<)B]
import org.flyware.util.page.Page; ["|AD,$%
{E1g+><
import com.adt.bo.Result; U<{8nMB
import com.adt.service.UserService; ln%xp)t
import com.opensymphony.xwork.Action; H((!
BRl
FVM:%S
JjT
/** BoZ])Y6=
* @author Joa ^N}zePy0
*/ ]Aap4+s
publicclass ListUser implementsAction{ T-ID{i
#mwV66'H
privatestaticfinal Log logger = LogFactory.getLog `RDlk
P5/K?I~/So
(ListUser.class); s$`g%H>
jV
Yt=j*"V
private UserService userService; KD?~ hpg
@Aa$k:_
private Page page; UH/) 4Wg
WF\
hXO
privateList users; "]J4 BZD
}rf_:
/* BE. v+'c"
* (non-Javadoc) {o"X8
* 54~`8f
* @see com.opensymphony.xwork.Action#execute() ?hUC#{
*/ 'U
',9
publicString execute()throwsException{ YSwAu,$jf
Result result = userService.listUser(page); Y: &?xR
page = result.getPage(); D>M
a3g
users = result.getContent(); =g4^tIYq
return SUCCESS; }M?\BH&
} 2|]$hjs
Q4e*Z9YJ
/** Sx)b~ *
* @return Returns the page. `s#0/t
*/ ,73kh
public Page getPage(){ tdSy&]P
return page; =ic"K6mhq
} h(]aP<49L
({ 'I;]AQ
/** !4-B
xeNY\
* @return Returns the users. z%cq%P8g
*/ =Q|_v}
publicList getUsers(){ L rV`P)$T
return users; JJ@O5
} ,grdl|Dg
?U'c;*O-
/** '>dsROB->
* @param page tDj~+lmdN
* The page to set. X v;} !z
*/ w$I<WS{J:Z
publicvoid setPage(Page page){ #T<<{ RA
this.page = page; t\44 Pu%
} 0>hV?A
$s$j</.q
/** q]Y [W1
* @param users VZ"W_U,
* The users to set. heQ<%NIA"
*/ XBQ]A89G
publicvoid setUsers(List users){ _ dFZR
this.users = users; 7"}<J7"})
} V,t&jgG*
9W{`$30
/** .)Xyzd
* @param userService 9_yO6)`
* The userService to set. -={Z::}S"
*/ L"|4
v
publicvoid setUserService(UserService userService){ ?kBi9^)N4
this.userService = userService; 'r`#u@TTZ
} v:otR%yt
} ?VC[%sjwn
3I0=^>A
E-Z6qZ^
A y ?;0w0
(`S32,=TS
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, GilaON*pK.
y&8' 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 !uaV6K
$`7cs}#
么只需要: aD
yHIh8
java代码: aH@Ux?-}
#i$/qk=N
d=<"sHO
<?xml version="1.0"?> &Xr@nt0H
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork V}?d
,.m`{
3;fuz Kk@b
1.0//EN" "http://www.opensymphony.com/xwork/xwork- l| 1O9I0Gd
ByP
1.0.dtd"> th&?
8m? 9?OV5
<xwork> l=(4o4um
kpc3l[.A
<package name="user" extends="webwork- 4-P'e%S
rn1^6qy)
interceptors"> /_Z--s>j
u\~dsD2)q
<!-- The default interceptor stack name /I[?TsXp
CD$0Z
--> SM> V
o+
<default-interceptor-ref 6"+/Imb-
y*ae 5=6(
name="myDefaultWebStack"/> G8}w|'0m
dP8b\H
<action name="listUser" *E"QFirk0
L_f u<W
class="com.adt.action.user.ListUser"> J23Tst#s
<param aA Hx^X^
>Mml+4<5
name="page.everyPage">10</param> H{*~d+:ol
<result xO8-vmf2
w2BIf[~t
name="success">/user/user_list.jsp</result> F+.:Ry FS
</action> *P4G}9B|9:
bzFwQi}>
</package> BR1oE3in
O 0Fw!IQk
</xwork> w7Do#Cv
ByR%2_6&
v-`RX;8
Ns.b8Y
x!CCSM;q
_yje"
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 N?`-$C ]
Zy0u@``
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。 8 VMe#41
kh3PEq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 n[Jpy[4g
C(i1 Vx<-
83,ATQg
02Z>#AE
m'h`%0Tc
我写的一个用于分页的类,用了泛型了,hoho Y`@:L'j
Gi})*U]P|
java代码: #K1VPezN
# biI=S
w4YuijhW
package com.intokr.util; _~f&wkc
{(r`&[
import java.util.List; D$|@:
mW
3DH}
YAUU
/** \W5fcxf
* 用于分页的类<br> BD6oN]
* 可以用于传递查询的结果也可以用于传送查询的参数<br> !Yx9=>R
* V4]t=3>
* @version 0.01 W0GDn
* @author cheng \XaKq8uE
*/ b,]QfC
public class Paginator<E> { .W_'6Q+
privateint count = 0; // 总记录数 1m$:Rn^
privateint p = 1; // 页编号 o+e:HjZZ
privateint num = 20; // 每页的记录数 B5'-v%YO+
privateList<E> results = null; // 结果 `Pa z
:q_(=EA
/** +C4UM9
* 结果总数 kWVaHZr
*/ 1"pvrX}
publicint getCount(){ G:'hT=8
return count; 4[=vt
} >OP[qj
iT f]Pd'
publicvoid setCount(int count){ {C6,h#|pg
this.count = count; '!8'Xo@Go3
} 8G&'ED_&
'6Lw<#It
/** wxy.&a]
* 本结果所在的页码,从1开始 6M({T2e
* H_H3Gp
* @return Returns the pageNo. X=Qa TV
*/ s,&tD
WU
publicint getP(){ fO6i
return p; (^x ,
} ?)x"+[2
h B@M5Mc$
/** ;JQ:S~K9
* if(p<=0) p=1 S6~&g|T,
* C!a#M{:
* @param p AmSrc.
*/ 0O,Q]P 82f
publicvoid setP(int p){ $^[^]Q
if(p <= 0) b/>L}/^PM
p = 1; U]!~C 1cmw
this.p = p; F^La\cZ*'
} /*v}.fH%
=8Bq2.nlR
/** .(D,CGtYb
* 每页记录数量 S5a?KU
*/ ZT;8Wvo
publicint getNum(){ Gp&o
return num; st91rV$y?
} j>D[iHrH
\piHdVD
/** ]Ak/:pu
* if(num<1) num=1 {`X O3
*/ qKL:#ny
publicvoid setNum(int num){ $0(~ID
if(num < 1) CAs8=N#H%
num = 1; Qv v~nGq$
this.num = num; /b
]Yya#
} ;s$bVGHr
BAy]&q|.
/** ^nPk;%`0
* 获得总页数 e#R'_}\yj
*/ T/9`VB%N
publicint getPageNum(){ ZKk*2EK]2z
return(count - 1) / num + 1; OVy ZyZ#
} $N@EH;{_0
D(z}c,
/** &@&0n)VTd
* 获得本页的开始编号,为 (p-1)*num+1 [H-r0Ah
*/ !%8|R]d
publicint getStart(){ 8M5a&