Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K4~Ox
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 U)8]pUI+/P
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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 =ndKG5
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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 t;3.;
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分页支持类: G]CY3xw98
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java代码: ri
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package com.javaeye.common.util; wn&2-m*a
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import java.util.List; 9K!='u`
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publicclass PaginationSupport { T!bu}KO
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publicfinalstaticint PAGESIZE = 30; Z]<_a)>
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privateint pageSize = PAGESIZE; s? Kn,6Y
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privateList items; gZ3!2T>
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privateint totalCount; e=2D^G#qE
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privateint[] indexes = newint[0]; x<(h9tB
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privateint startIndex = 0; '#PT C,0UJ
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public PaginationSupport(List items, int ;/@R{G{+~;
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totalCount){ FWg7e3
setPageSize(PAGESIZE); !T*izMX}
setTotalCount(totalCount); ArY'NE\Htt
setItems(items); w8qI7/
setStartIndex(0); q`P:PRgM
} kbY@Y,:w
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public PaginationSupport(List items, int L6m'u6:1{
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totalCount, int startIndex){ ?@_dx=su
setPageSize(PAGESIZE); Y*Pr
setTotalCount(totalCount); PsLCO(26
setItems(items); iaB5t<t1r
setStartIndex(startIndex); nV,a|V5Xm
} Ev%\YI!MaY
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public PaginationSupport(List items, int '&9b*u";x(
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totalCount, int pageSize, int startIndex){ + '`RJ,K+[
setPageSize(pageSize); STI8[e7{
setTotalCount(totalCount); gisZmu0
setItems(items); Xy._&&pt
setStartIndex(startIndex); MYjCxy-;A
} \m<*3eS
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publicList getItems(){ E~B
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return items; ZM" t.
} FQ5# v{
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publicvoid setItems(List items){ @c.pOX[]m,
this.items = items; R&?p^!`%
} e.N#+
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publicint getPageSize(){ '>Z
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return pageSize; \|M z'*
} <*L8kNykK
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publicvoid setPageSize(int pageSize){ G]{)yZ'}
this.pageSize = pageSize; LVSJK.B
} ;yr'K
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publicint getTotalCount(){ m9r
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return totalCount; IMj{n.y4
} .k}h'nE
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publicvoid setTotalCount(int totalCount){ 1c]GS&(RP
if(totalCount > 0){ y@F{pr+dA
this.totalCount = totalCount; T!8,R{V]4
int count = totalCount / a$ Z06j
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pageSize; ?Pa5skqR
if(totalCount % pageSize > 0) 4g|}]K1s
count++; 7v{Dwg
indexes = newint[count]; yovC~
for(int i = 0; i < count; i++){ ~x2azY2DP
indexes = pageSize * zMtx>VI
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i; LBTf}T\
} bO9X;}\6
}else{ 6]M(ElV1H
this.totalCount = 0; {$Qw]?Yv
} "5=Gu1
} ~OXPn9qPp
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publicint[] getIndexes(){ @PutUYz
return indexes; *~cq
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} `2G 0B@
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publicvoid setIndexes(int[] indexes){ !IcPO
this.indexes = indexes; 5LR
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} W;Ct[Y8m
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publicint getStartIndex(){ 05Ak[OOU>
return startIndex; L\aG.\
} 9J*.'Y
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publicvoid setStartIndex(int startIndex){ vr"O9L
w
if(totalCount <= 0) Kqm2TMO]>V
this.startIndex = 0; !ap}+_IA7^
elseif(startIndex >= totalCount) ,?S1e#
this.startIndex = indexes -V7dSi
{{qu:(_g
[indexes.length - 1]; Qu|H_<8g
elseif(startIndex < 0) !cW6dc^
this.startIndex = 0; ;?4EVZ#o
else{ yvv]iRk<
this.startIndex = indexes 7_HFQT1.N
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[startIndex / pageSize]; kntYj}F(
} Ir#]p9:x
} a5caryZ"z
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publicint getNextIndex(){ H%pD9'q~
int nextIndex = getStartIndex() + _0}u0fk
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pageSize; w{mw?0
if(nextIndex >= totalCount) Z-:T')#Cf
return getStartIndex(); tTOBKA89
else C cPOK2
return nextIndex; ZmI0|r}QbY
} G>=Fdt7Oc
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publicint getPreviousIndex(){ .exBU1Yk@
int previousIndex = getStartIndex() - <p/zm}?')
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pageSize; oz:"w
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if(previousIndex < 0) ;.'?(iEB
return0; zzK<>@c
else #N"m[$;QR
return previousIndex; {7jl) x3l
} S/"G=^~
}ZK%@b>
} k3K*{"z
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抽象业务类 `Fie'[F5,)
java代码: +5S>"KAUt0
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/** :s6aFiz
* Created on 2005-7-12 }4N'as/ZO
*/ Z#.1p'3qm1
package com.javaeye.common.business; EB|
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import java.io.Serializable; q8_(P&
import java.util.List; 3CgID6[Sy
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import org.hibernate.Criteria; e8rZP(g&g
import org.hibernate.HibernateException; \_WR:?l
import org.hibernate.Session; & XmaGtt
import org.hibernate.criterion.DetachedCriteria; .u>[m.
import org.hibernate.criterion.Projections; G<M0KU(
import i,h 30J
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org.springframework.orm.hibernate3.HibernateCallback; +q'\rpt
import #B<EMGH
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org.springframework.orm.hibernate3.support.HibernateDaoS Ie(i1?`A8
L/Q[N^ (^
upport; r[4n2Mys
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import com.javaeye.common.util.PaginationSupport; arDl2T,igF
@Wc5r#
public abstract class AbstractManager extends ss[`*89
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M
HibernateDaoSupport { 5afD;0D5TI
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privateboolean cacheQueries = false; RqgN<&g?
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privateString queryCacheRegion; gYD1A\
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publicvoid setCacheQueries(boolean >=[uLY[aK
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cacheQueries){ sqrLys_S
this.cacheQueries = cacheQueries; ~f h
} >x{("``D0y
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publicvoid setQueryCacheRegion(String q2*A'C
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queryCacheRegion){ 8cG?p
this.queryCacheRegion = hI'WfF!X
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queryCacheRegion; tw_o?9
} WeM38&dWY
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publicvoid save(finalObject entity){ =vbG'_[7
getHibernateTemplate().save(entity); $D1ha CL
} LH5Z@*0#
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publicvoid persist(finalObject entity){ h^SWb91"G
getHibernateTemplate().save(entity); 5EFt0?G
} {Rkd;`Q`!
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publicvoid update(finalObject entity){ _~z
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getHibernateTemplate().update(entity); eX+36VG\
} U?UU]>Q
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publicvoid delete(finalObject entity){ wtw=RA
getHibernateTemplate().delete(entity); }R%H?&P
} 4j#y?^s
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publicObject load(finalClass entity, =rA?,74
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finalSerializable id){ l~i?
return getHibernateTemplate().load %L=e%E=m
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(entity, id); )[ V8YiyU
} 3`bQ0-D;
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publicObject get(finalClass entity, UxGu1a
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finalSerializable id){ &t=:xVn-M
return getHibernateTemplate().get w"j>^#8
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(entity, id); `D4Wg<,9
} E_
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publicList findAll(finalClass entity){ K!6T8^JH
return getHibernateTemplate().find("from dKzG,/1W[m
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" + entity.getName()); _4by3?<c
} 1SExlU
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publicList findByNamedQuery(finalString wW%b~JX
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namedQuery){ if*V-$[I
return getHibernateTemplate 5i[O\@]5
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().findByNamedQuery(namedQuery); 74([~Qs _M
} ~su>RolaX
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publicList findByNamedQuery(finalString query, }b4 56J
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finalObject parameter){ n9Fq^^?
return getHibernateTemplate !]F`qS>
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().findByNamedQuery(query, parameter); G<C D4:V
} `y>m
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publicList findByNamedQuery(finalString query, 2XR!2_)O5
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finalObject[] parameters){ 1UMEbb
return getHibernateTemplate F@<cp ?dR
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().findByNamedQuery(query, parameters); EB3/o7)L
} g:!U,<C^a
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publicList find(finalString query){ /we]i1-9
return getHibernateTemplate().find ThV>gn5
k+"];
(query);
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} w[GEm,ZC
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publicList find(finalString query, finalObject `+Nv=vk
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parameter){ H^'%$F?Ss
return getHibernateTemplate().find Z`kVyuQ
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(query, parameter); OG{*:1EP
} !>F70
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public PaginationSupport findPageByCriteria ,~3rY,y-
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(final DetachedCriteria detachedCriteria){ }k.yLcXM
return findPageByCriteria +X#6dv$
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]U#of O
} 29=ob("
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public PaginationSupport findPageByCriteria 0=&S?J#!
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(final DetachedCriteria detachedCriteria, finalint ^Zvb3RJ g
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startIndex){ g(zeOS]q}
return findPageByCriteria dA~_[x:Z
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(detachedCriteria, PaginationSupport.PAGESIZE, ^P{y^@XI
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startIndex); >&\.{ aj
} } J?,?>Z
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public PaginationSupport findPageByCriteria WZ`i\s1#
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(final DetachedCriteria detachedCriteria, finalint <b'*GBw$
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pageSize, $hc=H
finalint startIndex){ \s[L=^!
return(PaginationSupport) p8XvfM
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getHibernateTemplate().execute(new HibernateCallback(){ }Tk:?U{
publicObject doInHibernate 13 h,V]ak
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(Session session)throws HibernateException { #*rJI3
Criteria criteria = ie[X7$@
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detachedCriteria.getExecutableCriteria(session); h<M1q1)
int totalCount = O`Qke
Z}
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((Integer) criteria.setProjection(Projections.rowCount /":/DwI'
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()).uniqueResult()).intValue(); CT_tJ
criteria.setProjection N"<.v6Z
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(null); W%5))R$
List items = OYxYlUq
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criteria.setFirstResult(startIndex).setMaxResults @C^x&Sjm
ez9F!1
(pageSize).list(); "*/IP9?]
PaginationSupport ps = lH?jqp
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new PaginationSupport(items, totalCount, pageSize, b&@]f2/
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startIndex); Y=|20Y\K
return ps; MCTJ^ g"D
} W4av?H
}, true); 3n)Kzexh
} LUxDP#~7
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public List findAllByCriteria(final u0<yGsEGD
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DetachedCriteria detachedCriteria){ A@_>9;
return(List) getHibernateTemplate .3UJ*^(?
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().execute(new HibernateCallback(){ _1Rw~}O
publicObject doInHibernate ,]ySBAO
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(Session session)throws HibernateException { )TVd4s(e
Criteria criteria = &+(D< U
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detachedCriteria.getExecutableCriteria(session); :4)x
return criteria.list(); Eo^m; p5
} 3
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}, true); oV['%Z'
} K%L6UQ;
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public int getCountByCriteria(final OAiW8BAe
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DetachedCriteria detachedCriteria){ wXp:XZ:]T
Integer count = (Integer) +\%]<YO
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getHibernateTemplate().execute(new HibernateCallback(){ yU/?4/G!
publicObject doInHibernate 6W1+@
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(Session session)throws HibernateException { B%u[gNZ
Criteria criteria = gfN=0Xj4
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detachedCriteria.getExecutableCriteria(session); IEm~^D#<=
return >G"fMOOkW
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criteria.setProjection(Projections.rowCount KI#v<4C$P
[ /*;}NUv
()).uniqueResult(); Xl2g Hh
} *)B \M>
}, true); !nJl.Y$
return count.intValue(); NTZ3Np`
} vf>d{F^rv
} Z@x&
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用户在web层构造查询条件detachedCriteria,和可选的 `EMGrw_
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 kk<%VKC
DC> R
PaginationSupport的实例ps。 0&|M/
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ps.getItems()得到已分页好的结果集 ZGX"Vn|YL
ps.getIndexes()得到分页索引的数组 ZBY}Mz$
ps.getTotalCount()得到总结果数 [cEGkz
ps.getStartIndex()当前分页索引 K\ B!tk
ps.getNextIndex()下一页索引 .j,xh )v"
ps.getPreviousIndex()上一页索引 mMZrBz7r
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3"0QW4A
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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 =&"pG`x
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一下代码重构了。 fM]nP4K`
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我把原本我的做法也提供出来供大家讨论吧: 5Y`4%*$
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首先,为了实现分页查询,我封装了一个Page类: d!&LpODI]*
java代码: s/~[/2[bnf
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/*Created on 2005-4-14*/ ]!P6Z?
package org.flyware.util.page; }>y~P~`S:
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/** U$a)lcJd
* @author Joa d@JavcR
* a>8]+@
*/ *qL2=2
publicclass Page { xk8NX-:
T=V{3v@zs
/** imply if the page has previous page */ *) \y52z
privateboolean hasPrePage; x3Fn'+
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/** imply if the page has next page */ *n@rPr-
privateboolean hasNextPage; MB>4Y]rtU
Te)%L*X
/** the number of every page */ d@Bd*iI<
privateint everyPage; J$jLGy& '
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/** the total page number */
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privateint totalPage; Zmk 9C@
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/** the number of current page */ MbTmdRf
privateint currentPage; UNrO$aX!1'
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/** the begin index of the records by the current #f=41d%
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query */ a)+*Gf7?
privateint beginIndex; 3<a|_(K
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}.=wQ_
/** The default constructor */ #.}&6ZP
public Page(){ .k!2{A
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} K7q R
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/** construct the page by everyPage {ueDwnZ
* @param everyPage 4>HQ2S{t
* */ cft@sY
public Page(int everyPage){ gd]k3XN$f
this.everyPage = everyPage; uD4W@*PYr
} x+Ly,9nc$
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/** The whole constructor */ m{yq.H[X
public Page(boolean hasPrePage, boolean hasNextPage, q{q;X{
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e
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int everyPage, int totalPage, )o::~ eu
int currentPage, int beginIndex){ [/J(E\9
this.hasPrePage = hasPrePage; -BrJ5]T>*
this.hasNextPage = hasNextPage; ]e?L,1-
this.everyPage = everyPage; &c=
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this.totalPage = totalPage; r,GgMk
this.currentPage = currentPage; catJC3
this.beginIndex = beginIndex; wI[J> 9Qn
} 'z};tIOKJk
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/** D<^K7tJui
* @return Ige*tOv2
* Returns the beginIndex. v@:m8Y(t
*/ ~y :?w(GD
publicint getBeginIndex(){ 6s:
return beginIndex; XE:bYzH
} '81WogH:
OL@' 1$/A
/** #4& <d.aw'
* @param beginIndex R+=Xr<`%U|
* The beginIndex to set. 2&<&q J
*/ ","to
publicvoid setBeginIndex(int beginIndex){ *,XT;h$'>
this.beginIndex = beginIndex; B,{Q[
} ,Mu"r!MK
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/** ) !l1
* @return v<]$,V]
* Returns the currentPage. 1F[W~@jW
*/ !4+@b
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publicint getCurrentPage(){ ]7%+SH,RdD
return currentPage; 'u%SI]*;>
} +?C7(-U>
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/** X0]5I0YP
* @param currentPage )s8{|) -
* The currentPage to set. ]nx5E_j2
*/ #D8u#8Dz
publicvoid setCurrentPage(int currentPage){ BHIC6i%
this.currentPage = currentPage; {pk&dB _Bu
} -Rr Qv(
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/** <ta#2
* @return R"{oj]d;$F
* Returns the everyPage. Jgzg[6
*/ '<hgc
publicint getEveryPage(){ [hKt4]R
return everyPage; 0"xD>ue&
} xayd_RB 9
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/** M[5fNK&nD
* @param everyPage "v5jYz5M
* The everyPage to set. d?1[xv;
*/ 6kHb*L Je
publicvoid setEveryPage(int everyPage){ G:!'hadw
this.everyPage = everyPage; A&qZ:&(OM
} ,
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/** \={A%pA;@{
* @return t,R4q*
* Returns the hasNextPage. #P-T4R
*/ 5$"IUq*
publicboolean getHasNextPage(){ WRfhxl
return hasNextPage; Vi\kB%
} Uk= L?t
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/** y@u,Mv
* @param hasNextPage Q%^!j_#
* The hasNextPage to set. aj@<4A=;
*/ 'mU7N<Q$qQ
publicvoid setHasNextPage(boolean hasNextPage){ #H/suQZN"g
this.hasNextPage = hasNextPage; Vh5Z'4N
} QAKA3{-(
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/** xBKis\b
* @return guWX$C-+1
* Returns the hasPrePage. @}iY(-V
*/ CxJkT2
publicboolean getHasPrePage(){ cuo'V*nWQ
return hasPrePage; 8+OcM
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} >Yt+LdG!-
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/** +JRPd.B"@
* @param hasPrePage 8:)itYE
* The hasPrePage to set. {/PiX1mn
*/ p}O[A`
publicvoid setHasPrePage(boolean hasPrePage){ >'96SE3
this.hasPrePage = hasPrePage; *Z
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} %P tdFz$
}KCb5_MDF
/** :~{x'`czJ
* @return Returns the totalPage. {|ChwM\x
* ]\Q9j7}37+
*/ t~@~XI5
publicint getTotalPage(){ <m!(eLm+B
return totalPage; ~k[q:$T
} Ec;{N
b Q6<R4
/** [
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* @param totalPage q]>m#yk
* The totalPage to set. t;e+WZkV
*/ /WWD;keP5
publicvoid setTotalPage(int totalPage){ !Al?B9KJ
this.totalPage = totalPage; I!OV+utF
} ~99DE78
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} Q1?09
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 .uGvmD<;x
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个PageUtil,负责对Page对象进行构造: }g\1JSJ%H
java代码: vOKWi:-U
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/*Created on 2005-4-14*/ 1ehl=WN
package org.flyware.util.page; ~$\9T.tre2
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import org.apache.commons.logging.Log; $xl>YYEBMH
import org.apache.commons.logging.LogFactory; byW9]('e
1!4-M$-
/** +.u)\'r;h
* @author Joa vL,:Yn@b
* yaD_c;
*/ 6pCQP
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publicclass PageUtil { Gec?
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privatestaticfinal Log logger = LogFactory.getLog d}2$J1`
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(PageUtil.class); ?mCino
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/** AsOkOS3
* Use the origin page to create a new page k,mgiGrQ
* @param page 7|/Ct;oO:
* @param totalRecords bkvm-$/
* @return X'
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*/ `3C dW
publicstatic Page createPage(Page page, int OrJuE[R.
{Hu@|Q\~&
totalRecords){ H>qw@JiO!
return createPage(page.getEveryPage(), "nzQ$E>?$
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page.getCurrentPage(), totalRecords); ]#fmih^
} #BZ2%\
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/** 7%Q?BH7{
* the basic page utils not including exception wIbxnn
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handler C2[* $ 1U
* @param everyPage a
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* @param currentPage `;7eu=
* @param totalRecords 5!b+^UR;z
* @return page 8?za&v
*/ ,DZoE~
publicstatic Page createPage(int everyPage, int %lbDcEsf9
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currentPage, int totalRecords){ ]+
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everyPage = getEveryPage(everyPage); \|gE=5!Am=
currentPage = getCurrentPage(currentPage); )43\q Iu\
int beginIndex = getBeginIndex(everyPage, zJ=lNb?q
3bd(.he2u
currentPage); (qbL=R"
int totalPage = getTotalPage(everyPage, j TyR+#Wn
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J$
totalRecords); +I$,Y~&`>
boolean hasNextPage = hasNextPage(currentPage, ){I0
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totalPage); Pss$[ %
boolean hasPrePage = hasPrePage(currentPage); 3OlXi9>3
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returnnew Page(hasPrePage, hasNextPage, lM|}K-2
everyPage, totalPage, \x7^ly$_
currentPage, V'q?+p]
a
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beginIndex); ]J(BaX4
} 3!u`PIQv
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privatestaticint getEveryPage(int everyPage){ :u9OD` D
return everyPage == 0 ? 10 : everyPage; GyZpdp!
} ]i:_^z)R
N*`qsv0
privatestaticint getCurrentPage(int currentPage){ >lV'}0u)
return currentPage == 0 ? 1 : currentPage; \:m1{+l
} c<a)Yqf"]
WqJrDj~
privatestaticint getBeginIndex(int everyPage, int SYd6D@^2j
}|OwUdE!R9
currentPage){ sW,JnR
return(currentPage - 1) * everyPage; {ew;
/;
} !kS/Ei
|kGQ~:k+P
privatestaticint getTotalPage(int everyPage, int YvG=P<_xw
9Wv}g"KY0
totalRecords){ {ldt/dl~
int totalPage = 0; AGGT]
58|
+,1 Ea )
if(totalRecords % everyPage == 0) )`BKEaf
totalPage = totalRecords / everyPage; 4:9N]1JCb
else r])V6 ^U
totalPage = totalRecords / everyPage + 1 ; :>y;*x0w
U38~m}c
return totalPage; aH?+^f"D
} ?2%;VKN4
a*&(cn
privatestaticboolean hasPrePage(int currentPage){ ;pw9+zo^M
return currentPage == 1 ? false : true; w>o/)TTJL
} h343$,))u
K3iQ/j~a q
privatestaticboolean hasNextPage(int currentPage, 7$*X
);zLgNx,
int totalPage){ I^Dm 3yz
return currentPage == totalPage || totalPage == wF9L<<&B
jU-aa+
0 ? false : true; ^=k=;
} 4T-"\tmg/
|R2p^!m
,{; *b
v
} 15S&,$1&
JW!.+
Q
S=gby
L~%7=]m
d%UzQ*s
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 :dqZM#$d
?qb35
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 _, E/HAX
):[}NDmC
做法如下: JA*+F1s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 SK#&%Yk
mITNx^p4f
的信息,和一个结果集List: d@p#{ -
java代码: dr(-k3ex
3FtL<7B'.
Se_]=>WI
/*Created on 2005-6-13*/ :0,yq?M
package com.adt.bo; M!kSt1
h5rR44
import java.util.List; 2n$Wey[
KIi:5Y
import org.flyware.util.page.Page; JEk'2Htx
gXlcB~!
/** 4y#XX[2Wj
* @author Joa >[Wjzg
*/ S2e3d
publicclass Result { ,<* I5:
zPc"r$'0U
private Page page; i%JJ+9N
.>eR X%
private List content; vc&v+5Y
b _<n]P*)
/** p0WUF\"
* The default constructor J_h.7V
*/ :-5[0Mx=
public Result(){ bD0l^?Hu!
super(); Ps>:|j+
} Ny^f'tsA
F_(~b
/** QM#Vl19>j(
* The constructor using fields 4`,7tj
* 5E-;4o;RI(
* @param page aZ4?!JW .
* @param content T{k_3[{0o
*/ Q(]m1\a
public Result(Page page, List content){ 7;o:r$08&}
this.page = page; NX,m6u
this.content = content; 6{buel(|e
} XZ~kXE;B(
&F
uPd}F
/** Rey+3*zUb
* @return Returns the content. _i}b]xfM
*/ o 2Nu@^+
publicList getContent(){ "t&=~eOe3
return content; [j-?)
} | J3'#7
&liON1GLM
/** <rj'xv
* @return Returns the page. x*7A33@i
*/ \jwG*a
public Page getPage(){ @01.Pd
return page; 7b[sW|{
} Y2x|6{ #
7P+1W
\
/** k_,7#:+
* @param content 'vd&r@N
* The content to set. fA6IW(_bi
*/ {P8d^=#q
public void setContent(List content){ X$>F78e*
this.content = content; EwzR4,r\M
} ;_I>`h"r
;DuVb2~+
/** + +}!Gfc?s
* @param page * @4@eQF
* The page to set. ^YLC {V
*/ V1]GOmXz
publicvoid setPage(Page page){ L;RE5YrH%6
this.page = page; /yG34) aB
} yjjq&Cn
} ;qgo=
qSvV|G
tn5%zJ#+
r%.k,FzGZY
['IH*gi
2. 编写业务逻辑接口,并实现它(UserManager, 1,wcf,
=wh[D$n$~
UserManagerImpl) irAXXg
java代码: i//H5D3
|SkQe[t
;;,7Jon2
/*Created on 2005-7-15*/ ]Lub.r
package com.adt.service; (bb!VVA
|(.\J`_e
import net.sf.hibernate.HibernateException; |T|m5V'l
b(0<,r8
import org.flyware.util.page.Page; KR>)Ek
,.<mj !YE
import com.adt.bo.Result; M`cxxDj&j
Hh%!4_AMw
/** {XOl &
* @author Joa '#+&?6 p
*/ .?45:Ey~g
publicinterface UserManager { ^lHy)!&A
E8!`d}\#
public Result listUser(Page page)throws `dZ|Ko%k
Tvx1+0Z%z
HibernateException; <F7a!$zQ
Hm2Y%
4i%
} >jI.$%L$
P 2WAnm
O%EA,5U.
{srP3ll
P
3uuIISK
java代码: 7X>IS#W]
@ZJL]TO
hP"2X"kz&
/*Created on 2005-7-15*/ OH
t)z.
package com.adt.service.impl; tAv3+
{ M**a
import java.util.List; j*.;6}\o
cyl%p$
import net.sf.hibernate.HibernateException; al2lC#Sy
K0gQr.J53
import org.flyware.util.page.Page; '9}&@;-_
import org.flyware.util.page.PageUtil; g{'f%bkG
aw*]b.f
import com.adt.bo.Result; =~;~hZj
import com.adt.dao.UserDAO; (ghI$oH
import com.adt.exception.ObjectNotFoundException; hZJ~zx~
import com.adt.service.UserManager; R;OPY?EeW
Vm%G
q
/** c1Ks{%iA
* @author Joa ~q ^o|?
*/ aC,adNub
publicclass UserManagerImpl implements UserManager { #^T`vTD-
G&*P*f1S
private UserDAO userDAO; Tx.N#,T|
le/j!
/** l 2Sar1~1
* @param userDAO The userDAO to set. ^\ [p6>
*/ [.}qi[=n
publicvoid setUserDAO(UserDAO userDAO){ v5M4Rs&t
this.userDAO = userDAO; LSC[S:
} ga
+,
P
@vl$[Z|
/* (non-Javadoc) ?\Z pVL<>
* @see com.adt.service.UserManager#listUser JR]2Ray
M_E,pg=rWI
(org.flyware.util.page.Page) D>5)',D8xi
*/ ~0p8joOH
public Result listUser(Page page)throws q=X<QhK
.aNh>`OT'
HibernateException, ObjectNotFoundException { ({E,}x
int totalRecords = userDAO.getUserCount(); X~r9yl>
if(totalRecords == 0) 6\7c:
throw new ObjectNotFoundException +@rFbsyJ.
$4{sPHi)I
("userNotExist"); A]bQUWt2
page = PageUtil.createPage(page, totalRecords); FDl/7P`b(
List users = userDAO.getUserByPage(page); <MS>7Fd2
returnnew Result(page, users); 0S5xmEzop
} 2_wpj;E
`Q*`\-8J
} !gkr?yhE
6:2* <
{?yVA
p(RF
$+WXM$N
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ) f~;P+
&| (K#|^@
询,接下来编写UserDAO的代码: .eN"s'
3. UserDAO 和 UserDAOImpl: Ar>B_*dr
java代码: 3P0z$jh"H
G u`xJ
2Z{?3mAb;
/*Created on 2005-7-15*/ I%.nPOQ 8
package com.adt.dao; e`0C0GaP
HAH\#WE
import java.util.List; 3V]dl)en%
Kl. *Q
import org.flyware.util.page.Page; YW7w>}aW
9fX0?POG
import net.sf.hibernate.HibernateException; N_g=,E=U%
"w"a0nv
/** !PIg,
* @author Joa }C @xl9S "
*/ Py*WHHO
publicinterface UserDAO extends BaseDAO { boiP_*|M Y
+j: &_
publicList getUserByName(String name)throws pBAAwHD
R_j.k3r4d
HibernateException; ?sHZeWZ(
B}04E^
publicint getUserCount()throws HibernateException; V~PGmn[V
l'l&Zqd
publicList getUserByPage(Page page)throws T4W20dxL7
h_t`)]-
HibernateException; -|'@:cIZ
oJM;CN
} F+Kju2
xlZh(pf
t5 >ma:^j
nOyG7:
OR&pGoW
java代码: G>pedE\
48,*sTRq
"#Z e3Uy\
/*Created on 2005-7-15*/ ^%*qe5J
package com.adt.dao.impl; @|\;#$?XW3
JAHmmNlW
import java.util.List; pej-W/R&
>c@! EPS
import org.flyware.util.page.Page; ecm+33C
pKXSJ"Xo
import net.sf.hibernate.HibernateException; "u^2!d
import net.sf.hibernate.Query; ;PVE= z+y
1<h@^s ;
import com.adt.dao.UserDAO; qh bagw~
4grV2xtX
/** ^XyC[ G@[
* @author Joa ;xq;c\N
*/ W\Il@Je;
public class UserDAOImpl extends BaseDAOHibernateImpl ,h5 FX^
Lm$KR!z
implements UserDAO { Y".?j5f?
B$c'^
)
/* (non-Javadoc) fC"?r6d
* @see com.adt.dao.UserDAO#getUserByName gRs@T<k2
`0s3to%7
(java.lang.String) "@ZwDg`
*/ s'/_0
publicList getUserByName(String name)throws W;Dik%^tg
`-s]dq
HibernateException { vzAY+EEx
String querySentence = "FROM user in class l [ m_<1L
(CDh,ZN;|
com.adt.po.User WHERE user.name=:name"; Aa-OMo;~
Query query = getSession().createQuery mr>E'd.'
1"A"AMZf
(querySentence); |I]G=.*E
query.setParameter("name", name); ).Z
U0fV
return query.list(); /L`qOr2E
} , Sf:R4=
N#OO{`":Z`
/* (non-Javadoc) d<]eJ{
* @see com.adt.dao.UserDAO#getUserCount() KVC18"|f
*/ }P!:0w3
publicint getUserCount()throws HibernateException { =?M{B1;H
int count = 0; ZjK'gu8*
String querySentence = "SELECT count(*) FROM RXO}mu]Iu
;x)f;!e+
user in class com.adt.po.User"; 9-Qu5L~
Query query = getSession().createQuery ],<pZ1V;
_y [B/C,q
(querySentence); x;&iLQZh
count = ((Integer)query.iterate().next 1OFrxSg
V[*<^%
()).intValue(); FYaBP;@J%
return count; b5
AP{
#
} ,PWMl[X
%Bn n\{Az
/* (non-Javadoc) Y0Rk:Njc
* @see com.adt.dao.UserDAO#getUserByPage *]S&V'Di
G7#<Jo<8
(org.flyware.util.page.Page) |3EKK:RE
*/ `g'9)Xf4KT
publicList getUserByPage(Page page)throws &K"qnng/y
GZiN&}5e
HibernateException { U7xQ 5lph
String querySentence = "FROM user in class ^hwTnW9Z1:
H1ox>sC
com.adt.po.User"; O=}jg0k
Query query = getSession().createQuery /kFw(l_.
u3vw[k
(querySentence); ,h9N,bIQg
query.setFirstResult(page.getBeginIndex()) fXx !_Z
.setMaxResults(page.getEveryPage()); Qvhy9Cr;
return query.list(); \4 hB1-
} Z2{G{]EV(
)WF*fcx{
} ET=-r
ARJ} h
&n2dL->*#
-*0U&]T
Cq%1j[
至此,一个完整的分页程序完成。前台的只需要调用 |D[4G6&
/HM0p
userManager.listUser(page)即可得到一个Page对象和结果集对象 05[k@f$n
E<4'4)FHuQ
的综合体,而传入的参数page对象则可以由前台传入,如果用 d7!,
Ub*O*nre
webwork,甚至可以直接在配置文件中指定。 QR{pph*zn-
uY$BZEuAZ
下面给出一个webwork调用示例: ~*^aCuq\
java代码: #BwkbOgr
jf~-;2
<sC.
/*Created on 2005-6-17*/ U=\!`_f':
package com.adt.action.user; /UPe@
4A~1Z,"%v(
import java.util.List; GMYfcZ/,K
_(J/$D
import org.apache.commons.logging.Log; Qj',&b
import org.apache.commons.logging.LogFactory; @vkO(o
import org.flyware.util.page.Page; Pa\"l'!>^
J^<}fRw
import com.adt.bo.Result; -}Q^A_xK
import com.adt.service.UserService; :]k`;;vh
import com.opensymphony.xwork.Action; 72{Ce7J4
6]5e(J{Fz
/** ?*2Uw{~}
* @author Joa NE2P
"mY
*/ ;-!j,V+$h
publicclass ListUser implementsAction{ 7C@%1kL
iF'qaqHWY4
privatestaticfinal Log logger = LogFactory.getLog AvEd?
7,&M6<~
(ListUser.class); rq_0"A
r*XEne
private UserService userService; pLea 4
?0k4l8R
private Page page; )$7-CNWr~
s2ixiv=
privateList users; -TU^*
A~MIFr /8
/* F>/"If#
* (non-Javadoc) #Qnl,lf
* ~Ddlr9Ej
* @see com.opensymphony.xwork.Action#execute() pGdo:L?
*/ 6A,-?W'\
publicString execute()throwsException{ ~gJJ@j 0n
Result result = userService.listUser(page); aokV'6
page = result.getPage(); U+wfq%Fz
users = result.getContent(); 1aBQ.-E-
return SUCCESS; T.x"a$AU
} 1NQstmd{
G~N$bF^R)
/** D*o5fPvFO
* @return Returns the page. *Y/}EX!F
*/ ~rICPR
public Page getPage(){ moT*r?l
return page; "{"745H5
} L92vb zP
Gbrc!3K2
/** 3yp?|>e
* @return Returns the users. &2\^S+4
*/ $2'Q'Mx[gd
publicList getUsers(){ (>a8h~Na
return users; \6WVs>z
} 4<(U/58a*
.5K}R<
/** #$;i 4a
* @param page z(g6$Y{
* The page to set. ~D1&CT#s
*/ 5eJMu=UpR
publicvoid setPage(Page page){ pf[m"t6G~
this.page = page; +fRABY5C
} cypb6Q_
tTcff9ee
/** 7wB*@a-
* @param users i4s_:%+
* The users to set. ,!7\?=G6}v
*/ |rr<4>)X
publicvoid setUsers(List users){ o<Y[GW1pg
this.users = users; %(YU*Tf~
} #WqpU.
.mwB'Ll
/** v-ZTl4j$
* @param userService
A\:u5(
* The userService to set. QpI\\Zt6
*/ (N[R`LN
publicvoid setUserService(UserService userService){ ^sqTgrG
this.userService = userService; KMll8X
} u/ZV35z
} Xdl7'~k
T:!f_mu|
|9Pi*)E
=V>inH
"J"RH:$v
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ec3zoKtV
T]UrKj/iF
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ^{{0ajI9C
K=N8O8R$y
么只需要: M'|?*aNK
java代码: W87kE?,
E/@
Ou7nk:I@
<?xml version="1.0"?> tV"Jh>Z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K3xt,g
\]|(w*C
1.0//EN" "http://www.opensymphony.com/xwork/xwork- RaC8Sq7hW
7Q0vwKC8>
1.0.dtd"> 4Is Wp!`W
V~MyX&`
<xwork> 8DGPA
`R
m<1
<package name="user" extends="webwork- V>(>wSR
ac%x\e$
interceptors"> sv)4e)1
`l ?(zy:R
<!-- The default interceptor stack name zK>}x=
9Ecc~'f
--> WP5Vev9*+
<default-interceptor-ref GJIZu&C
]ONBr(M\
name="myDefaultWebStack"/> hdDL92JVg
e/b
|
sl
<action name="listUser" y<kg;-& 8
-unQ4G
class="com.adt.action.user.ListUser"> :u`gjj$:s
<param 5}TTf2&Xo#
2$Umqt
name="page.everyPage">10</param> %^l&:\ hy
<result L, 2;-b|
!@>q^_Gez
name="success">/user/user_list.jsp</result> Uc9hv?
</action> ?OFfU 4
w1LZ\nA<
</package> ,z~"Mst
Ym?VF{e,
</xwork> \$!D^%~;
f h:wmc'
xy-Vw"I[bh
C8%MKNPd
eq@-J+
lE$(*1H
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值
0:$pJtx"
R-tZC9
@
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。 (5e4>p&+
@M6F?;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 C(vQR~_
0xH&^Ia1B
5p ,HkV
ul]hvK{2
|>b;M,`OO
我写的一个用于分页的类,用了泛型了,hoho tBVtIOm9
SPm2I(at7
java代码: T1%}H3
R&Ss ET.
x,HD,VQR/
package com.intokr.util; {s{+MbD
P 1
import java.util.List; #'n.az=1
Qe_C^(P
/** jp|*kBDq\
* 用于分页的类<br> $,0EV9+af
* 可以用于传递查询的结果也可以用于传送查询的参数<br> j /@<=
* ;rV+eb)I
* @version 0.01 Vi>P =i
* @author cheng ~V0 GRPnI
*/ *BvdL:t
public class Paginator<E> { G8'
privateint count = 0; // 总记录数 K"ly\$F
privateint p = 1; // 页编号 n@6vCdk.
privateint num = 20; // 每页的记录数 '
H4m"
privateList<E> results = null; // 结果 8#[2]1X^8
DXQ]b)y+N
/** Dl,sl>{
* 结果总数 MI-S}Qoe
*/ 5F!i%{XQvm
publicint getCount(){ TpI8mDO\W
return count; /1_O5'5+v
} ^]Q.V
*j=58d`n
publicvoid setCount(int count){ cP\ZeG#<
this.count = count; VVcli*
} 2vhP'?;K
uG/'9C6Z
/** <~aKwSF[wW
* 本结果所在的页码,从1开始 \UX9[5|
* ,v`03?8l(
* @return Returns the pageNo. p'6XF{
*/ *!E~4z=
publicint getP(){ 5>UQ 3hWo
return p;
lnK
} `VvQems
EPR85[k
/** \En"=)A
* if(p<=0) p=1 Bsha)<
* G/#m.=t
* @param p 9XKqsvdS
*/ Zz+v3o0
publicvoid setP(int p){ pvb&vtp
if(p <= 0) r;"D>IM\
p = 1; <
Wp)Y
this.p = p; E" >`
} ZJm$7T)V
bC98<if
/** +H *6:
* 每页记录数量 a)c;z@r
*/ g^x=y
publicint getNum(){ g$zGiqzMK
return num; q2'}S
A/
} .p> ".q
I
)=`DEbT
/** <&2<>*/.y
* if(num<1) num=1 }fv7WhQ
*/ l9OpaOVfJ
publicvoid setNum(int num){ v*FbvrY
if(num < 1) sC.r$K+k5
num = 1; 4_sJ0 =z-
this.num = num; e6mm;@F>
} 12?!Z
gat;Er
/** >)G[ww[
* 获得总页数 %NJ0Y(:9(
*/ f F)M'C
publicint getPageNum(){ *9xxX,QT8Q
return(count - 1) / num + 1; 5f?GSHA}
} |K;9b-\
RAk"C!&^m
/** TJZ/lJU
* 获得本页的开始编号,为 (p-1)*num+1 HY1K(T
*/ =S\^j"
publicint getStart(){ v\MQ?VC
return(p - 1) * num + 1; 4b((,u$
} *o\AP([@
2+DK:T[
/** %3"3V1
* @return Returns the results. TC44*BHq
*/ O[eU{;P
publicList<E> getResults(){ 3e47UquZ
return results; oXqJypR 2
} l4.ql1BX@y
?e4H{Y/M
public void setResults(List<E> results){ _-TW-{7bh
this.results = results; j~V$q/7S
} 0Z]HH+Z;
G`jvy@
public String toString(){ iY?#R&
StringBuilder buff = new StringBuilder lMh>eX
s]6;*mI2
(); u-s*k*VHoc
buff.append("{"); vnVT0)Lel
buff.append("count:").append(count); 4)k-gKS*
buff.append(",p:").append(p); : _:)S
buff.append(",nump:").append(num); G4P*U3&p
buff.append(",results:").append C'y2!Q/"
.w@B )f*
(results); \P9ms?((A
buff.append("}"); >B~?
}@^Gk
return buff.toString(); (n:A`]
} q+oc^FD?@
WQ8 "Jj?k6
} ^'M^0'_"v
iu*&Jz)D>
4e
eh+T