Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $@D*/@
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 vbD""
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 gSa !zQN6
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 D6dliU?k
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分页支持类: BTzBT%mP
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java代码: X"jL
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package com.javaeye.common.util; P BVF'~f@j
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import java.util.List; pO/vD~C>
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publicclass PaginationSupport { Vx}e,(i
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publicfinalstaticint PAGESIZE = 30; ih|;H:"^
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privateint pageSize = PAGESIZE; x5Ue"RMl+
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privateList items; Z2L7US-
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privateint totalCount; v.-r %j{I
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privateint[] indexes = newint[0]; ]K3bDU~
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privateint startIndex = 0; V'tqsKQ!
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public PaginationSupport(List items, int ~_hA{$
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totalCount){ [_KV;qS%/
setPageSize(PAGESIZE); r#A*{4wz
setTotalCount(totalCount); S0Ur{!9\#^
setItems(items); B^!-%_q
setStartIndex(0);
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} pw&k0?K#
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public PaginationSupport(List items, int m2H?VY.^K
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totalCount, int startIndex){ aNn4j_V(
setPageSize(PAGESIZE); fP[S.7F+No
setTotalCount(totalCount); 2FW"uYA;6
setItems(items); 2z.~K&+x
setStartIndex(startIndex); _s+G02/q1
} {{Qbu}/@
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public PaginationSupport(List items, int ]bAVOKm-
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totalCount, int pageSize, int startIndex){ eZ$M#I=o
setPageSize(pageSize); 2">de/jS
setTotalCount(totalCount); `rXb:P7m{j
setItems(items); t 9t
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setStartIndex(startIndex); !MrQ-B (
} :.tL~%
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publicList getItems(){ Y]_$+Si:NK
return items; |g>Q3E
} )+"5($~
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publicvoid setItems(List items){ u(fZ^
this.items = items; u|Oc+qA(
} C(9"59>{]y
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publicint getPageSize(){ Y]*&\Ex"\
return pageSize; %Oo
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} \4LTViY]
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publicvoid setPageSize(int pageSize){ (c&%1bJ
this.pageSize = pageSize; IBvn
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} S8B?uU
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publicint getTotalCount(){ s_}6#;
return totalCount; , O/IY
} :5['V#(o
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publicvoid setTotalCount(int totalCount){ 6"
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if(totalCount > 0){ ]=%6n@z'
this.totalCount = totalCount; Fw*O ciC
int count = totalCount / Gov.;hy
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pageSize; yoJ.[M4q
if(totalCount % pageSize > 0) `|Hk+V
count++; '!ks $}$`h
indexes = newint[count]; 9J~\.:jH-
for(int i = 0; i < count; i++){ j:qexhtho
indexes = pageSize * ^%!SKhRIK
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} WF-jy7+
}else{ r{t6Vv2J
this.totalCount = 0; O@
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} $+f=l~/s
} "OA{[)fw"
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publicint[] getIndexes(){ x@QNMK.7
return indexes; a|=^
} k0O5c[j
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publicvoid setIndexes(int[] indexes){ w~'}uh
this.indexes = indexes; S 6_:\Q
} a$h^<D
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publicint getStartIndex(){ QxA( *1
return startIndex; 83I 5n&)
} _'ebXrbZB
#AB5}rPEI
publicvoid setStartIndex(int startIndex){ ]jm:VF]4
if(totalCount <= 0) ?]D))_|G
this.startIndex = 0; utBrH
elseif(startIndex >= totalCount) Ef?hkq7X<
this.startIndex = indexes 7)Vbp--b#
iF Mf[qBg
[indexes.length - 1]; i\l}M]Z#
elseif(startIndex < 0) <G|i5/|7
this.startIndex = 0; i9De+3VqKK
else{ :fwt PvLo
this.startIndex = indexes zeuj
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[startIndex / pageSize]; 8PH4v\tJEK
} ;Vc|3
} In?#?:Q@&
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publicint getNextIndex(){ d@1^U9sf
int nextIndex = getStartIndex() + H<n"[u^@E
fqY'Uq$=
pageSize; p4MWX12
if(nextIndex >= totalCount) '8\9@wzv
return getStartIndex(); D*[Jrq,
else $,]U~7S
return nextIndex; ~Gz9pBv1
} e3W~6P
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publicint getPreviousIndex(){ GM'yOJo
int previousIndex = getStartIndex() - Y I;iG[T,&
TEY~E*=}$
pageSize; CYQ)'v
if(previousIndex < 0) G%: 3.:E"
return0; (YYg-@IO
else GVJ||0D
return previousIndex; OR!W3
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} ![_0GFbT
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} JffaT_"\
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=#[oi3k
抽象业务类 P
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java代码: V`#2jDz
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/** sH;_U)ssH
* Created on 2005-7-12 7+hF1eoI
*/ isd-b]@:Lc
package com.javaeye.common.business; TUC)S&bC
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import java.io.Serializable; B+U:=591
import java.util.List; wB[f%mHs
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import org.hibernate.Criteria; <>9!oOa
import org.hibernate.HibernateException; 1u7D:h>#
import org.hibernate.Session; ]#^v754X^T
import org.hibernate.criterion.DetachedCriteria; tx>7?e8E
import org.hibernate.criterion.Projections; E5)0YYjHZ
import 9l&q}
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org.springframework.orm.hibernate3.HibernateCallback; :,aY|2si
import zA>X+JH>iw
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org.springframework.orm.hibernate3.support.HibernateDaoS t~j6w sx;
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upport; <MkvlLu((o
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import com.javaeye.common.util.PaginationSupport; @}g3\xLiK
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public abstract class AbstractManager extends EG3,TuDH8
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HibernateDaoSupport { ;[R6rVHe{
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privateboolean cacheQueries = false; o>,r<
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privateString queryCacheRegion; yiC7)=
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publicvoid setCacheQueries(boolean EUuSN| a
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cacheQueries){ `HQ)][
this.cacheQueries = cacheQueries; 4BCe;Q^6
} G@`F{l
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publicvoid setQueryCacheRegion(String -i2rcH
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queryCacheRegion){ |_TI/i>?'
this.queryCacheRegion = |*NZ^6`@
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queryCacheRegion; sb{K%xi%
} zG6l8%q'UE
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publicvoid save(finalObject entity){ "4\
getHibernateTemplate().save(entity); 7[;!e nO
} >bf.T7wy
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publicvoid persist(finalObject entity){ s<F*kLib
getHibernateTemplate().save(entity); Zyz#xMmM
} {+WY,%e
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publicvoid update(finalObject entity){ dz([GP'-*
getHibernateTemplate().update(entity); . &j+&
} .yZLC%}
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publicvoid delete(finalObject entity){ ]<\YEz&A
getHibernateTemplate().delete(entity); Tt)z[^)%
} 0<\|D^m=&h
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publicObject load(finalClass entity, b+|Jw\k
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finalSerializable id){ ~#3{5*
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return getHibernateTemplate().load M.mn9kw`
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(entity, id); ewk7:zS/?
} vw2E$ya
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publicObject get(finalClass entity, 5;0w({1l
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finalSerializable id){ (^}t
return getHibernateTemplate().get ?lsK?>uU
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(entity, id); bLai@mL&a
} e`qrafa
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publicList findAll(finalClass entity){ ?^%[*OCCC!
return getHibernateTemplate().find("from "frZ%mv
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" + entity.getName()); gE2(E0H
} /fp8tL2Y
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publicList findByNamedQuery(finalString jDY
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namedQuery){ -`k>(\Q<d
return getHibernateTemplate 9BtGzI\
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().findByNamedQuery(namedQuery); TI7$J#
} X#&5?oq`
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publicList findByNamedQuery(finalString query, FQ<x(&/NF
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finalObject parameter){ h(/? 81:
return getHibernateTemplate PF`uwx@zH
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().findByNamedQuery(query, parameter); eA!Z7 '
} .A< HM}
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publicList findByNamedQuery(finalString query, IEy$2f>Ns
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finalObject[] parameters){ aA|{r/.10K
return getHibernateTemplate %[p*6&V
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().findByNamedQuery(query, parameters); }) -V,\
} HqWWWCWal
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publicList find(finalString query){ S!8<|WO^t
return getHibernateTemplate().find uBbQJvL
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(query); Pw<?Dw]m
} ~DK.Y
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publicList find(finalString query, finalObject utZI'5i
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parameter){ Mgw#4LU
return getHibernateTemplate().find 89&9VX^A
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(query, parameter); #,#_"
} ;O hQBAC
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ %HG+|)b
return findPageByCriteria ?C2(q6X+s
,"`20.Lv
(detachedCriteria, PaginationSupport.PAGESIZE, 0); #'&-S@/nQs
} -w"I
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public PaginationSupport findPageByCriteria %>*?uO`z[
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(final DetachedCriteria detachedCriteria, finalint 'bl9fO4v
oT{9P?K8
startIndex){ u;t<rEC2
return findPageByCriteria 1Gr^,Ry
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(detachedCriteria, PaginationSupport.PAGESIZE, 0BC@wV
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startIndex); R1LirZlzJ
} )jL@GW
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public PaginationSupport findPageByCriteria jo"nK,r
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(final DetachedCriteria detachedCriteria, finalint 5>9Q<*
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pageSize, RDbNC v#
finalint startIndex){ _E?tVx.6
return(PaginationSupport) */K[B(G
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getHibernateTemplate().execute(new HibernateCallback(){ En&7 e
publicObject doInHibernate Hi[lN7ma8
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(Session session)throws HibernateException { c/K#W$ l
Criteria criteria = e W8cI)wU
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detachedCriteria.getExecutableCriteria(session); ^ZsIQ4 @`
int totalCount = F[\T'{
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((Integer) criteria.setProjection(Projections.rowCount js"Yh
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()).uniqueResult()).intValue(); _W(xO
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criteria.setProjection R WY>`.su
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(null); -4QZ/ *
List items = LkJq Bg
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criteria.setFirstResult(startIndex).setMaxResults G%~V b
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(pageSize).list(); [Z/P[370
PaginationSupport ps = h's[)
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new PaginationSupport(items, totalCount, pageSize, @].s^ss9_
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startIndex); KN_n :`cH{
return ps; w-WAgAch
} k`>qb8,
}, true); R,D/:k'~k
} 3)VO{Cj!
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public List findAllByCriteria(final 49E|
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DetachedCriteria detachedCriteria){ G:b6Wf
return(List) getHibernateTemplate Z6gwAvf<
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().execute(new HibernateCallback(){ A&1EOQ=N
publicObject doInHibernate pu MVvo
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(Session session)throws HibernateException { Z%o.kd"
Criteria criteria = 6'*6tS
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detachedCriteria.getExecutableCriteria(session); g s1
return criteria.list(); |6-9vU!LK?
} T|\sN*}\8J
}, true); |u`YT;`!"-
} Jy:@&c
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public int getCountByCriteria(final ,Z|O y|+'
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DetachedCriteria detachedCriteria){ fQ~~%#z1
Integer count = (Integer) 5%(
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getHibernateTemplate().execute(new HibernateCallback(){ f|~'(~Sr
publicObject doInHibernate =X'EDw
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(Session session)throws HibernateException { Onqapm0
Criteria criteria = hlyh8=Z6o
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detachedCriteria.getExecutableCriteria(session); ~jKIuO/
return TH4f"h+B3"
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criteria.setProjection(Projections.rowCount ';.TQ_I7Y
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()).uniqueResult(); Y]R=z*i%
} ,FYA*}[
}, true); Q +hOW-
return count.intValue(); br0\O
} Sy.%>$ z
} ce4rhtkV
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用户在web层构造查询条件detachedCriteria,和可选的 B7A.~'=
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 MeV4s%*O+
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PaginationSupport的实例ps。 ^38kxwh
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ps.getItems()得到已分页好的结果集 :1'1n
ps.getIndexes()得到分页索引的数组 x2~fc
ps.getTotalCount()得到总结果数 r_ 9"^Er
ps.getStartIndex()当前分页索引 zGO_S\
ps.getNextIndex()下一页索引 ;,/G*`81B
ps.getPreviousIndex()上一页索引 5-a^Frmg#"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HU
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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 %,N-M]Jf
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一下代码重构了。 WFug-#;e
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我把原本我的做法也提供出来供大家讨论吧: DS|x*w'I
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首先,为了实现分页查询,我封装了一个Page类: ENYc.$r
java代码: w0>5#jq#r
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/*Created on 2005-4-14*/ kyB>]2
package org.flyware.util.page; T/L\|_:'
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/** |c]L]PU
* @author Joa BH^cR<<j
* }/ xdHt
*/ k3
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publicclass Page { odeO(zuU
~8Ef`zL
/** imply if the page has previous page */ ,E(M<n|.
privateboolean hasPrePage; wGz_IL.D
w@N)Pu
/** imply if the page has next page */ F0'o!A#|(
privateboolean hasNextPage; sGMnm
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/** the number of every page */ ]w8h#p
privateint everyPage; S@L%X<Vm
0"@p|nAa
/** the total page number */ .}tpEvAw}
privateint totalPage; |Pse=_i
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/** the number of current page */ A.P*@}9
privateint currentPage; YBk* CW9
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/** the begin index of the records by the current '(:R-u!pp
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query */ l~`JFWur]
privateint beginIndex; ,+_gx.H2j
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/** The default constructor */ No/D"S#
public Page(){ _ZuI x=!
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} GsWf$/iC:
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/** construct the page by everyPage 6nk.q|n:g
* @param everyPage oA
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* */ # f{L;
public Page(int everyPage){ ,Hc,]TPC4
this.everyPage = everyPage; ?7*J4.
} -uK@2}NZ
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/** The whole constructor */ CYk"
public Page(boolean hasPrePage, boolean hasNextPage, ?rwHkPJ{*
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int everyPage, int totalPage, %t-}dC&
int currentPage, int beginIndex){ ]O M?e
this.hasPrePage = hasPrePage; 8g
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this.hasNextPage = hasNextPage; iHOvCrp+X
this.everyPage = everyPage; #mv~1tL
this.totalPage = totalPage; 4vPKDd
this.currentPage = currentPage; cT^x^%
this.beginIndex = beginIndex; B\7 80p<
} t4,(W`
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/** ^t)alNGos
* @return O$&4{h`
* Returns the beginIndex. k{C|{m
*/ )0@&pEObm
publicint getBeginIndex(){ w3oe.hWP3N
return beginIndex; 9O#?r82
} 8F`799[p
}KL( -Ui$
/** jowR!rqf
* @param beginIndex &
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* The beginIndex to set. P0szY"}
*/ "CWqPcr
publicvoid setBeginIndex(int beginIndex){ }2_i<4,L
this.beginIndex = beginIndex; y
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} Os|F
FkIT/H
/**
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* @return X=b]Whuv
* Returns the currentPage. rexy*Xv`2p
*/ _;5N@2?
publicint getCurrentPage(){ gNo}\
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return currentPage; V_7QWIdiy>
} vJ!<7 l&
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/** /H[ !v:U
* @param currentPage $P~Tt 4068
* The currentPage to set. 3MFb\s&Fq
*/ IDv|i.q3
publicvoid setCurrentPage(int currentPage){ r*s)T`T}}
this.currentPage = currentPage; |h1Y3
} syLpnNx=
cY\"{o"C
/** n<>/X_m
* @return AVv 8Hhd
* Returns the everyPage. 0Fm,F&12
*/ _:,U$W
publicint getEveryPage(){ H;eOrX{GT
return everyPage; -7l)mk
} MDKiwT@#
#~88[i-6
/** q\6ZmKGnT
* @param everyPage ~w9ZSSb4
* The everyPage to set. ZYX(Cf
*/ 0E#3XhU
publicvoid setEveryPage(int everyPage){ dy*CDRU4
this.everyPage = everyPage; at `\7YfQp
} /WKp\r(Hp
rn8t<=ptH3
/** #>\+6W17U
* @return v5o@ls
* Returns the hasNextPage. 86\B|!
*/ Arb-,[kwN
publicboolean getHasNextPage(){ LK[%}2me
return hasNextPage; X>y6-%@
} b}#ay2AR
K Z)p\p<1
/** m2$Qp{C6H
* @param hasNextPage WH^rM`9
* The hasNextPage to set. R+O[,UM^I~
*/ GiN\@F!
publicvoid setHasNextPage(boolean hasNextPage){ FsYsQ_,R3
this.hasNextPage = hasNextPage; u?n{r
} [3QKBV1\
w_!]_6%{b
/** Hh1OD?N)
* @return oUwu:&<Orm
* Returns the hasPrePage. 0Bpix|mq
*/ 6+[7UH~pm^
publicboolean getHasPrePage(){ f}>S"fFI
return hasPrePage; ;MR(Eaep
} ~?)ST?&
mT2Fn8yC1
/** PjkJsH
* @param hasPrePage c}>p"
* The hasPrePage to set. "Q ~-C|x
*/ z2lEHa?w
publicvoid setHasPrePage(boolean hasPrePage){ #E(
n
this.hasPrePage = hasPrePage; \WeGO.i-
} ?0VLx,kp
BK1Aq3*)
/** D 4\T`j:
* @return Returns the totalPage. i`1QR@11
* G6b\4}E
*/ n3kYVAgF
publicint getTotalPage(){ M6J/S
return totalPage; _ADK8a6%)
} :A{ US9D
|H4/a;]~
/** jci'q=Vpu
* @param totalPage JUlV$b.)J
* The totalPage to set. 4V`ypFme
*/ YbrsXp"
publicvoid setTotalPage(int totalPage){ qeyBZ8BG
this.totalPage = totalPage; HEjrat;5
} Wh)QCp0|n
? h$>7|
} 7QlA/iKqK
5!PU+9Kh
F*_mHYa;
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 IRZ?'Im
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个PageUtil,负责对Page对象进行构造: p&L`C|0
java代码: hfGA7P"
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/*Created on 2005-4-14*/ @Ooh}V#J
package org.flyware.util.page; %@{);5[
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import org.apache.commons.logging.Log; 24Y~x`W
import org.apache.commons.logging.LogFactory; ,z?Re)qm
#n'tpp~O
/** \DE`tkV8
* @author Joa j_?U6$xi
* k.DDfuKN
*/ uSs~P%@6|
publicclass PageUtil { GJA3
,OLN%2Sq
privatestaticfinal Log logger = LogFactory.getLog ^AUmIyf_
[Uezi1I
(PageUtil.class); pt;kN&A^
{}ZQK
/** m.MOn3n]
* Use the origin page to create a new page X}yEMe{T
* @param page XY5I5H_U
* @param totalRecords nJYcC"f
* @return rBP!RSl1
*/ 7 3k3(rZ
publicstatic Page createPage(Page page, int u8*Uia*vwH
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totalRecords){ =S-'*F
return createPage(page.getEveryPage(), 6|05-x|
$H/3t? 6h`
page.getCurrentPage(), totalRecords); ~PUz/^^
s
} w $7*za2
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/** \HDRr*KO
* the basic page utils not including exception
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Frt_X %
handler a`CsL Bv&
* @param everyPage PCs+`
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* @param currentPage [KR`%fD0
* @param totalRecords #nc{MR#R
* @return page +gTnq")wnI
*/ c8gdY`
publicstatic Page createPage(int everyPage, int //W<\
S*:b\{[f>
currentPage, int totalRecords){ ;""V s6
everyPage = getEveryPage(everyPage); ;h3uMUCml
currentPage = getCurrentPage(currentPage); nVoPTr
int beginIndex = getBeginIndex(everyPage,
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+E QRNbA
currentPage); )L`0VTw'M
int totalPage = getTotalPage(everyPage, 16 o3ER
z@cL<.0CE
totalRecords); &gkloP@
boolean hasNextPage = hasNextPage(currentPage, QhK]>d.
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totalPage); fw_V'l#\
boolean hasPrePage = hasPrePage(currentPage); `ejE)VL=8h
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returnnew Page(hasPrePage, hasNextPage, pHY~_^B4&
everyPage, totalPage, R{3f5**0
currentPage, jGEUl=W
)5Kzq6.
beginIndex); &|H?J,>
} V2%FWo|
MZE8Cvq0
privatestaticint getEveryPage(int everyPage){ X#(?V[F]
return everyPage == 0 ? 10 : everyPage; x<"e} Oo
} &@A(8(%
dapQ5JT/
privatestaticint getCurrentPage(int currentPage){ 5A/G?
return currentPage == 0 ? 1 : currentPage; 8|?$KLz?F>
} G7`7e@{
\<~[uv'
privatestaticint getBeginIndex(int everyPage, int Q5iuK#/
u
Y/Q]NT
currentPage){ &`<j!xlG
return(currentPage - 1) * everyPage; 8(D>ws$
} w@4q D
yjpV71!M
privatestaticint getTotalPage(int everyPage, int ?K{CjwE.M
ycRy!0l
totalRecords){ dV8mI,h
int totalPage = 0; qr(SAIX"
vKDRjrF-
if(totalRecords % everyPage == 0) Se*GR"Z+
totalPage = totalRecords / everyPage; sW#6B+5_k
else 5FnWlFc
totalPage = totalRecords / everyPage + 1 ; z:|4S@9
.wx;!9
return totalPage; AU$W=Z*
} Zo22se0)
nvxftbfE^D
privatestaticboolean hasPrePage(int currentPage){ N9Yc\?_NU_
return currentPage == 1 ? false : true; Tul_/` An
} |~CN]N
;58l_ue
privatestaticboolean hasNextPage(int currentPage, s6w</
Z6X?M&-Lz
int totalPage){ veAGUE
%3
return currentPage == totalPage || totalPage == Sq}hx
>"B95$x5
0 ? false : true; oKiBnj5J
} (J][(=s;a
wnP#.[,V
<Jo_f&&{
} <n>Kc}c
FlRbGg^
+o!".Hp
q.t>:`
7Xm pq&g
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。 U/m6% )Yx(
;c_X
^"d
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 0CQ\e1S,#
\q(RqD
做法如下: 'd^U!l
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 r@H<@Vuc
vN-#Ej.
u
的信息,和一个结果集List: m]+g[L?-
java代码: Xp{+){Iu
,Zb]3
*;(LKRV
/*Created on 2005-6-13*/ +%=Ao6/#
package com.adt.bo; hJ>{`Tw
L=Fm:O'#2
import java.util.List; T c4N\Cy
h2zuPgz,
import org.flyware.util.page.Page; ,g#=pdX;
1 +O- g
/** jnYFA[Ab
* @author Joa hUcG3IOBf
*/ ot]E\g+!
publicclass Result { .KGW#Qk8
_+S`[:;a
private Page page; O$E3ry+?
^UZEdR;
private List content; KO<Yc`Fs
H ZIJKk(
/** cnXIE{9M
* The default constructor Fa,a)JY>
*/ 9Y- Sqk+
public Result(){ jmmm0,#D
super(); bg*4Z?[dd
} G?{BVWtl}
l&(,$RmYp
/** 5u
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* The constructor using fields 4$+1jjC]>~
* 8=FP92X
* @param page KTD# a1W
* @param content "~9 !o"
*/ ;WC]Lf<Z^
public Result(Page page, List content){ 29
L~SMf
this.page = page; r+217fS>
this.content = content; KcglpKV`
} E5UI
Xa.Qt.C
/** p\wE})mu
* @return Returns the content. ~&[Wqn@MZ
*/ **d3uc4y
publicList getContent(){ lV:R8^d
return content; %'nM!7w@I
} }xn\.M:ic
V{p*N*
/** + O=wKsGD
* @return Returns the page. F``$}]9KHD
*/ #Sr_PEo
_
public Page getPage(){ -LJbx<'
return page; I#zrz3WU
} %kS +n_*
IExo#\0'6
/** SEq_37
* @param content -~~"}u
* The content to set. ='q:Io?T
*/ 2i;G3"\
public void setContent(List content){ |G~LJsXW!v
this.content = content; yjaX\Wb[z[
} 4P(Y34j
H-~V:OCB~
/** zdrCr0Rx,
* @param page &*B=5W;6^u
* The page to set. 2--"@@
*/ 3k py3z[%
publicvoid setPage(Page page){ jxU1u"WU
this.page = page; o;.PZi2k
} d>*?C!xE
} 3,+)3,N
E%t_17,=j
im_WTZz2P
Jiyt,D*wX
m{
.'55
2. 编写业务逻辑接口,并实现它(UserManager, (ec?_N0=
Xi^3o
UserManagerImpl) .p NWd
java代码: Fd*)1FQKT
$73 7oV<
:^tw!U%y1
/*Created on 2005-7-15*/ j-8v$0'
package com.adt.service; M>VT$!Lx
0W<:3+|n4
import net.sf.hibernate.HibernateException; N@lTn}U
LF vKF .
import org.flyware.util.page.Page; zs<W>gBq
(=}cc
import com.adt.bo.Result; Mo\LFxx>4{
v=zqj}T
/** 9>\P]:
* @author Joa "Lk-R5iFd
*/ @.;] $N&J
publicinterface UserManager { D0Yl?LU3
^AkVmsv;;
public Result listUser(Page page)throws 0)`{]&
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n
JUXpl
HibernateException; #5-5N5-1
u@tJu'X
} 6:O3>'n
!
/;@kXN
Fk@A;22N
bmgK6OyVR
/. GHR
java代码: FtXd6)_S
}CnqJ@>C5
R("g ]
/*Created on 2005-7-15*/ SQhk)S
package com.adt.service.impl; wDswK "T
T+ey>[
import java.util.List; .}n,
WPi^;c8
import net.sf.hibernate.HibernateException; YUU|!A8x
NWWag}
import org.flyware.util.page.Page; mX3~rK>@~
import org.flyware.util.page.PageUtil; vp@ %wxl!:
@RGVcfCG)
import com.adt.bo.Result; Y?W"@awE"\
import com.adt.dao.UserDAO; eIBHAdU+g/
import com.adt.exception.ObjectNotFoundException; .|[ZEXq
import com.adt.service.UserManager; =r=[e}&9
Pz#D9.D0
/** eSo/1D
* @author Joa c6FKpdn%
*/ "~jSG7h
publicclass UserManagerImpl implements UserManager { 0`.3`Mk
F4'g}yOLd
private UserDAO userDAO; qI;"yG-x-
]H<5]({F
/** &$F4/2|b%
* @param userDAO The userDAO to set. `##qf@M
*/ iU3)4(R
publicvoid setUserDAO(UserDAO userDAO){ T&Z%=L_Q
this.userDAO = userDAO; ,RIGV[u
} Q;{[U!\:
$0>>Z
/* (non-Javadoc) GWo^hIfJ
* @see com.adt.service.UserManager#listUser iJ.P&T9
eAKK uML
(org.flyware.util.page.Page) R|aA6} /I
*/ n!=%MgF'*p
public Result listUser(Page page)throws PhF.\Wb
ReE-I/n8f
HibernateException, ObjectNotFoundException { zK`fX
int totalRecords = userDAO.getUserCount(); 4np,"^c
if(totalRecords == 0) #RAez:BI
throw new ObjectNotFoundException V^fSrW]
7KIOI,qb6
("userNotExist"); L".Qf|b*
page = PageUtil.createPage(page, totalRecords); td!WgL,m
List users = userDAO.getUserByPage(page); , ,1H#;j
returnnew Result(page, users); )D\cm7WX^[
} x/D"a|
(O {5L(
} <Y~?G:v6+
4a3Xz,[(a
k[lYdk
EQZu-S`kv
E*V UP5E
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q-([3%
qjcy{@ j
询,接下来编写UserDAO的代码: 2,,zN-9mt
3. UserDAO 和 UserDAOImpl: 9Fb|B
java代码: fFP>$
T \%{zz_(
s`"o-w\$>
/*Created on 2005-7-15*/ [DrG;k ?
package com.adt.dao; C@+"d3
3GVE/GtU
import java.util.List; )9'eckt
%-ih$ZY
import org.flyware.util.page.Page; l%"[857
k^3 ?Z2a
import net.sf.hibernate.HibernateException; Z#7T!/28
*?jU$&Qpj*
/** 46(Vq|
* @author Joa ~5Wr
|qg%{
*/ 'Gwa[ |6i
publicinterface UserDAO extends BaseDAO { :&D>?{b0
|Y'xtOMX
publicList getUserByName(String name)throws U 7mA~t2E
Eq$Q%'5*ua
HibernateException; ly`p)6#R=
@Dc?fyY*o<
publicint getUserCount()throws HibernateException; \2cbZQx
tI50z khaB
publicList getUserByPage(Page page)throws `:WVp~fn
4T#B7wVoM
HibernateException; g-^Cf
g7*c wu
} Z}bUvr XP
ECHl9;
+
|rJ1/T.9
.5=Qfvi*
(?MRbX]@
java代码: BM bT:)%
dhl[JC~ _
4k'2FkDA
/*Created on 2005-7-15*/ S"?py=7
package com.adt.dao.impl; p x;X}Cd
A:Y]<jt
import java.util.List; \+OP!`
jxA`RSY
import org.flyware.util.page.Page; O8BxXa@5
:x e/7 -
import net.sf.hibernate.HibernateException; $47cKit|k:
import net.sf.hibernate.Query; \(UEjlo
fdr.'aMf%
import com.adt.dao.UserDAO; #PYTFB%
G<.p".o4
/** 'Y23U7 n0B
* @author Joa hpJ[VKe
*/ MGn:Gj"d
public class UserDAOImpl extends BaseDAOHibernateImpl O+Z[bis`
Bkg/A;H
implements UserDAO { U" eP>HHp
Id8^6FLw
/* (non-Javadoc) $Yfm>4
* @see com.adt.dao.UserDAO#getUserByName EoLF7j<W
lhZWL}l
(java.lang.String) vn;_|NeSf
*/ F 7+Gt
Ed
publicList getUserByName(String name)throws |a@$KF$
p"^^9'`=
HibernateException { "B`yk/GM]
String querySentence = "FROM user in class e6s-;
> o{(f
com.adt.po.User WHERE user.name=:name"; YpQ/ )fSEV
Query query = getSession().createQuery zjd]65P
=IBdnEz:M
(querySentence); 2YvhzL[um
query.setParameter("name", name); 0Eq.l <
return query.list(); MsOO''o
} Ko% &~C_
T
xRa&1
/* (non-Javadoc) Alh"G6
* @see com.adt.dao.UserDAO#getUserCount() b6=.6?H@4f
*/ k#k !AcC
publicint getUserCount()throws HibernateException { IQ$l!)
int count = 0; Nx4_Oc^hY
String querySentence = "SELECT count(*) FROM PN0l#[{EN
}vBk,ED
user in class com.adt.po.User"; .Ajs0 T2
Query query = getSession().createQuery ^T\JFzV
Ikiv+Fq(
(querySentence); (mXV5IM
count = ((Integer)query.iterate().next ,2u-<8
& i|x2;
v
()).intValue(); 4)Y=)#=
return count; <rc3&qmd
} P\bW k p0
<~# ZtD$G
/* (non-Javadoc) ` +]9+:tS
* @see com.adt.dao.UserDAO#getUserByPage !?B9 0(
fx|$(D@9
(org.flyware.util.page.Page) l= 5kd.{
*/ R{S{N2+p(
publicList getUserByPage(Page page)throws M@@"-dy
bG
nBV7b
HibernateException { 2GECcx53
String querySentence = "FROM user in class c0ET]
*ie#9jA
com.adt.po.User"; m;o \.s
Query query = getSession().createQuery $oK,&_
.(Q3M0.D
(querySentence); ^!H8"CdC3
query.setFirstResult(page.getBeginIndex()) Er}
xB~<t
.setMaxResults(page.getEveryPage()); '3=[xVnv
return query.list(); Uxx=$
} OI B~W
(_-<3)q4
} o PRvd_~
0}$",M!p
gsufd{{
Uj}iMw,
^.jIus5
至此,一个完整的分页程序完成。前台的只需要调用 PIP2(-{ai
SiHZco
I
userManager.listUser(page)即可得到一个Page对象和结果集对象 g<oSTAw
y]eH@:MJ;A
的综合体,而传入的参数page对象则可以由前台传入,如果用 hf P}+on%
W|~Lmdzj
webwork,甚至可以直接在配置文件中指定。 msg&~"Z
&O5%6Sv3d
下面给出一个webwork调用示例: ~Bn#AkL
java代码: "
M8j?
FX )g\=ov
(qHI>3tpY
/*Created on 2005-6-17*/ T#?KY
package com.adt.action.user; {y=H49
oz%ZEi\bW
import java.util.List; (i>VJr
Zeyhr\T
import org.apache.commons.logging.Log; {c|nIwdB
import org.apache.commons.logging.LogFactory; 5~4I.+~8
import org.flyware.util.page.Page; -tZ2
N
x,
a[ p\1
import com.adt.bo.Result; hu[=9#''$
import com.adt.service.UserService; <9eQ
import com.opensymphony.xwork.Action; Wfkm'BnV
2S}%r4$n}
/** qQ%zSJ?
* @author Joa ORlz1&hW
*/ HH+NNSRO
publicclass ListUser implementsAction{ {'G@- +K
h;f5@#F
privatestaticfinal Log logger = LogFactory.getLog iyrUY
K)$.0S9d
(ListUser.class); `ysPEwA|
y!GjC]/
private UserService userService; \\
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5gZ0a4
private Page page; K,%H*1YKK
IJO`"da
privateList users; "QA CQ-
Fgxh?Wd9
/* hJ#U;GL
* (non-Javadoc) ~\DC
)
* ~}w(YQy=y
* @see com.opensymphony.xwork.Action#execute() &$jg *Kr
*/ hf0G-r_ow
publicString execute()throwsException{ qO[6?q=c:
Result result = userService.listUser(page); }Y[Z`w
page = result.getPage(); ja70w:ja
users = result.getContent(); MX6*waQ-<
return SUCCESS; +jO1?:Lr
} B`<(qPD
-\\}K\*MJ
/** 7J./SBhB
* @return Returns the page. |f'U_nE#R/
*/ enlk)_btp
public Page getPage(){ bP&o]?dN
return page; %l[Cm4
} 1K^blOLXe
rX%#Q\0h
/** hE-`N,i}
* @return Returns the users. ST)l0c+Y>
*/ I>bLgt]u3
publicList getUsers(){ Pk[f_%0
return users; C\dQ6(3}\
} jJ?MT#v
TbU\qcm]]
/** `da6}Vqj:
* @param page p9XHYf72
* The page to set. (\.[pj%-O
*/ [yL%+I
publicvoid setPage(Page page){ <%<}];bmFL
this.page = page; I(P|`"
} 2GXAq~h@
?cCh?>h
/** *ZyIbT
* @param users mJ<rzX
* The users to set. RW48>4f/+
*/ F*>:~'%
publicvoid setUsers(List users){ uf\Hh -+p
this.users = users; >},O_qx
} t= "EbPE
^v*ajy.>
/** kf_s.Dedw
* @param userService 5H:NY|
* The userService to set. -]~U_J]
*/ >pO[S[
publicvoid setUserService(UserService userService){ j\q1b:pE
this.userService = userService; wd~e3%JM
} ,!F'h:
} ?+D_*'65D
Run)E*sf
9 }|Bs=q
oiJa1X
5*[zIKdt2
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, b:\I*WJ
LpaY Md;
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 FT/H~|Z>
jIv+=b#oT
么只需要: <tuh%k
java代码: ].pz
bPC {4l
[{6]i J
<?xml version="1.0"?> \r^=W=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K:z|1V
x^8x z5:O
1.0//EN" "http://www.opensymphony.com/xwork/xwork- I?J$";A
rl'YyO}2
1.0.dtd"> :IV4]`
{a `kPfP
<xwork> :m_0WT
6S])IA&VJ
<package name="user" extends="webwork- Xp1xhb*^
Zg5@l3w
interceptors"> )M#~/~^f+
<d#9d.<
<!-- The default interceptor stack name [esjR`u
ETV|;>v
--> )K -@{v^|
<default-interceptor-ref /XEcA5C<
eg~$WB;1
name="myDefaultWebStack"/> vlw2dY@^
/8q7pwV
<action name="listUser" |iLeOztuE
i
cQsA
class="com.adt.action.user.ListUser"> lEQ63)Z
<param zu(/c
Ec8Y}C,{7<
name="page.everyPage">10</param> cInzwdh7
<result Bqv Oi~l
)_NQ*m
name="success">/user/user_list.jsp</result> FfI$3:9
</action> m=z-}T5y!T
-kq=W_
</package> o
]2=5;)
,COSpq]6
</xwork> (:,N?bg
@{@x2'-A
Itr yiU9
$V]D7kDph*
_MR|(mV
@za?<G>!'e
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 +I/7eIG?|
~ d/Doi
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 v#IW;Rj8
%g5weiFM
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 E+dr\Xhv
DvF`KHsy
.r[DqC
4FQU$f
Q5;Km1(
我写的一个用于分页的类,用了泛型了,hoho r9%4q4D?>9
j1v fp"J1
java代码: k
<A>J-|
7Nh6 `
_I<eJ\
package com.intokr.util; [ k^6#TQcn
$bF.6
import java.util.List;
8yOzD
/jC0[%~jV
/** R5X<8(4p
* 用于分页的类<br> ]Q-ON&/
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #PVgx9T=_
* IJD'0/R'c
* @version 0.01 Axk
p
* @author cheng nrUrMnlg
*/ 9^4^EY#
public class Paginator<E> { 58mzh82+
privateint count = 0; // 总记录数 KG'4;Z5J
privateint p = 1; // 页编号 .Ig`v
privateint num = 20; // 每页的记录数 zY(w`Hm2
privateList<E> results = null; // 结果 t.j q]L
R7KHfXy'm
/**
kej@,8
* 结果总数 }bIEW ho
*/ @0A0\2
publicint getCount(){ O1JGv8Nr
return count; }z,4IHNn
} 7xVI,\qV
bo$xonV @y
publicvoid setCount(int count){ b}9K"GT
this.count = count; Xleoh2&M
} :)q/8 0@
r*>XkM& M
/** y{?
6U>_
* 本结果所在的页码,从1开始 hDl& K E
* NjdAfgA
* @return Returns the pageNo. -J:](p
*/ @H@&B`K d
publicint getP(){ ?fnJ`^|-r
return p; k>K23(X
} g/lv>*+gS
~fAdOh
/** ^ ^}
* if(p<=0) p=1 Z2PLm0%:
* d{9rEB?
* @param p PP[{c
*/ ,`P,))
publicvoid setP(int p){ GJy><'J,!>
if(p <= 0) 00%$?Fyk
p = 1; 1#(,Bq4
this.p = p; EqUiC*u8{I
} :QUZ 7^u
Dd!MG'%hlb
/** H6/@loO!Xy
* 每页记录数量 hNyYk(t^
*/ @xtcjB9
publicint getNum(){ L
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return num; =Q.2:*d.
} gEO#-tMjOQ
VMad ]bEf
/** )!|K3%9
* if(num<1) num=1 w/d9S(
*/ e|):%6#
publicvoid setNum(int num){ 2~2
if(num < 1) @gE
+T37x2
num = 1; ok-sm~ bp
this.num = num; n4>
} >`5iq.v
n2Dnpe:
/** O(~`fN?n
* 获得总页数 Q'*-gg&)
*/ }}cVPB7
publicint getPageNum(){ BtBy.bR
return(count - 1) / num + 1; f|Z3VS0x
} iWCN2om
H3QAIsGS
/** \
CV(c]
* 获得本页的开始编号,为 (p-1)*num+1 WT'P[RU2
*/ lLmVat(
publicint getStart(){ ? RB~%^c!
return(p - 1) * num + 1; ]B3 0d
} MO9}Itg
xPQO}wKa
/** 0Ny0#;P
* @return Returns the results. ;?=nr 5;q
*/ KT{<iz_
publicList<E> getResults(){ >kz5azV0
return results; V/"0'H\"1
} 6xk"bIp
9{70l539
public void setResults(List<E> results){ /-^gK^
this.results = results; WE|L{
} fS1N(RZ1
y"cK@sOo
public String toString(){ `Wn0v2@a(~
StringBuilder buff = new StringBuilder
PLFM[t/
j:)
(`
(); V,|l&-
buff.append("{"); m ~fqZK
buff.append("count:").append(count); xb8fV*RO8A
buff.append(",p:").append(p); }YU#}Ip@
buff.append(",nump:").append(num); X2dTV}~i
buff.append(",results:").append w][
;
_?1<
(results); !ye%A&
buff.append("}"); VG&|fekF
return buff.toString(); %dw-}1X
} BB--UM{7
%lv2 ;-
} 6}C4 SZ
U+@yx>!
[xO^\oQa=c