Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 f&ri=VJY\T
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Htn''adg5
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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 ,UE>@;]
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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 #'lqE)T
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分页支持类:
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java代码: Ap)[;_9BD
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package com.javaeye.common.util; PbpnjvVrM
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import java.util.List; H68~5lJY^]
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publicclass PaginationSupport { (eEs0
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publicfinalstaticint PAGESIZE = 30; Tc.k0n%W:b
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privateint pageSize = PAGESIZE; U?.cbB,
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privateList items; q"C(`S.@
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privateint totalCount; 9qcA+gz:|
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privateint[] indexes = newint[0]; IVdM}"+
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privateint startIndex = 0; , tb\^
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public PaginationSupport(List items, int "`q:
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totalCount){ vA"MTncv
setPageSize(PAGESIZE); D6L5X/#
setTotalCount(totalCount); K}e:zR;;^
setItems(items); X" m0||
setStartIndex(0); |0N6]%r
} CaE1h9
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public PaginationSupport(List items, int aTL u7C\-e
INjr$'*
totalCount, int startIndex){ R&MdwTa
setPageSize(PAGESIZE); VxA?LS`
setTotalCount(totalCount); rK@XC +`S
setItems(items); o4PJ9x5R!
setStartIndex(startIndex); ]/ffA|"U`
} 9S_PZH
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public PaginationSupport(List items, int 1=U NA :t<
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totalCount, int pageSize, int startIndex){ 8gn12._x
setPageSize(pageSize); 7H!/et?S,
setTotalCount(totalCount); PXrv2q[5?
setItems(items); ;eY.4/*R
setStartIndex(startIndex); !> 2kH
} 'nRoa7v(
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publicList getItems(){ dYxX%"J
return items;
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} xm$-:N0q
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publicvoid setItems(List items){ {'@`:p&3r
this.items = items; a2%xW_e
}
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publicint getPageSize(){ ``:+*4e9
return pageSize; A}3dx!?7j
} kVe4#LT
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publicvoid setPageSize(int pageSize){ &m=73RN
this.pageSize = pageSize; j[Q9_0R~lR
} bGtS! 'I
X 7R&>Pf
publicint getTotalCount(){ *YO^+]nmY
return totalCount; sD ,=_q@
} gzd<D}2F~
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publicvoid setTotalCount(int totalCount){ 4^(aG7
if(totalCount > 0){
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this.totalCount = totalCount; E*AI}:or;
int count = totalCount / @s.civ!Yk
{|{;:_.>
pageSize; 'zhv#&O
if(totalCount % pageSize > 0) !*e1F9k
count++; c4V%>A
indexes = newint[count]; i z%wozf
for(int i = 0; i < count; i++){ cNl NJ
indexes = pageSize * cw3j&k
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i; Lm3~< vP1e
} =n<Lbl(7
}else{ CC
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this.totalCount = 0; zQ~ax!}R
} Ms
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} zI,z <-
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publicint[] getIndexes(){ [nASMKK0
return indexes; mgE
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} WCD)yTg:ES
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publicvoid setIndexes(int[] indexes){ ZA+w7S3
this.indexes = indexes; ^).
} +l hJ8&
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publicint getStartIndex(){ `Kbf]"4q
return startIndex; 8+@j %l j
} =6'Fm$R
r yNe=9p
publicvoid setStartIndex(int startIndex){ v>0I=ut
if(totalCount <= 0) p""\uG'
this.startIndex = 0; J9-n3o
elseif(startIndex >= totalCount) X;]Ijha<*
this.startIndex = indexes \q@Co42n\
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[indexes.length - 1]; M}e}3w
elseif(startIndex < 0) <?>tjCg'
this.startIndex = 0; I(H9-!&
else{ k+BY 3a
this.startIndex = indexes GTM@9^
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[startIndex / pageSize]; 2m^qXE$
} eLIZ<zzW0}
} B$M4f7
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publicint getNextIndex(){ :%_h'9Qq
int nextIndex = getStartIndex() + U@9v(TfV
&F:%y(;{Y
pageSize; <JIqkGeAi
if(nextIndex >= totalCount) $R%tD.d3
return getStartIndex(); D-FT3Culw
else {53|X=D64
return nextIndex; `S+n,,l
} U(gYx@
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publicint getPreviousIndex(){ RzU9]e
int previousIndex = getStartIndex() - :{
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NL,6<ZOon,
pageSize; _Q 'f^Kj
if(previousIndex < 0) .'>d7
return0; zs6rd83#
else Y-lwS-Ii
return previousIndex; OLo?=1&;;
} ^WF_IH&
aLl=L_
} %l,CJd5
Q zg?#|
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抽象业务类 g/(BV7V
java代码: *eGG6$I
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/** &kcmkRRG
* Created on 2005-7-12 YYL3a=;`a
*/ E
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package com.javaeye.common.business; +IMt$}7[
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import java.io.Serializable; ht#,v5oG>f
import java.util.List; EeHghq
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import org.hibernate.Criteria; 9oIfSr,y
import org.hibernate.HibernateException; m%'T90mi
import org.hibernate.Session; :|8!w
import org.hibernate.criterion.DetachedCriteria; 3xN_z?Rg
import org.hibernate.criterion.Projections; gF`hlYD
import Xvk+1:D
~^'WHuzPy
org.springframework.orm.hibernate3.HibernateCallback; ?gBFfi
import ^q`RaX)
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org.springframework.orm.hibernate3.support.HibernateDaoS IwBO#HR~)
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upport; _DAqL@5n
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import com.javaeye.common.util.PaginationSupport; v}id/brl
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public abstract class AbstractManager extends u1gD*4+
Nf)SR#;
HibernateDaoSupport { M2;6Cz>,P
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privateboolean cacheQueries = false; xs
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privateString queryCacheRegion; | #b/EA9
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publicvoid setCacheQueries(boolean sgnc$x"
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cacheQueries){ nN^lY=3
this.cacheQueries = cacheQueries; <2fy(9y
} =**Q\Sl
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publicvoid setQueryCacheRegion(String $d,/(*Y#-
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queryCacheRegion){ kkW }:dBl
this.queryCacheRegion = R\Ckk;<$
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queryCacheRegion; }#2(WHf=<
} 6y "]2UgQk
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publicvoid save(finalObject entity){ ]omBq<ox'Y
getHibernateTemplate().save(entity); 'vYt_T
} G*,7pc
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publicvoid persist(finalObject entity){ fQwLx
getHibernateTemplate().save(entity); t BG
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} ;JMmr-@
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publicvoid update(finalObject entity){ fz?woVn
getHibernateTemplate().update(entity); :`lP+y?a1
} \j-:5M#m
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publicvoid delete(finalObject entity){ o?cNH
getHibernateTemplate().delete(entity); jP0TyhM
} @6%7X7m
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publicObject load(finalClass entity, mi7~(V>
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finalSerializable id){ 6'x3g2C/
return getHibernateTemplate().load )/Gi-::
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(entity, id); PRNq8nmxC
} ; xQhq*
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publicObject get(finalClass entity, j,SZJ{ebXg
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finalSerializable id){ gIIF17|Z
return getHibernateTemplate().get 6__HqBQ
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(entity, id); /{/mwS"W
} !N_eZPU.v
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publicList findAll(finalClass entity){ kBnb9'.A1
return getHibernateTemplate().find("from c4r9k-w0E
1~},}S]id
" + entity.getName()); OF)*kiJ
} yjq|8.L[
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publicList findByNamedQuery(finalString ori[[~OyB
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namedQuery){ Vg :''!4t2
return getHibernateTemplate 'NCx <0*
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().findByNamedQuery(namedQuery); f"NWv!
} SG1AYUs
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publicList findByNamedQuery(finalString query, ]"htOO
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finalObject parameter){ F\GNLi
return getHibernateTemplate -N6ek`
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().findByNamedQuery(query, parameter); e\f\CMb
} &Vu-*?
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publicList findByNamedQuery(finalString query, a;nYR5f
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finalObject[] parameters){ vS[\j
return getHibernateTemplate ;Bw3@c
e**'[3Y
().findByNamedQuery(query, parameters); (
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} dTlEEgR
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publicList find(finalString query){ F1L[C4'
return getHibernateTemplate().find N3a ]!4Y\
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(query); =vriraV"
} :S7[<SwL
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publicList find(finalString query, finalObject tA'5ufj*:
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parameter){ Q`4Ia<5B
return getHibernateTemplate().find }W[=O:p
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(query, parameter); l<ZHS'-;8
} 2R^Eea
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public PaginationSupport findPageByCriteria Fpwhyls
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(final DetachedCriteria detachedCriteria){ Ke]'RfO\
return findPageByCriteria ,^<39ng
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); +Jn\`4/J:
} 0ia-D`^me
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public PaginationSupport findPageByCriteria ]1|7V|N6
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(final DetachedCriteria detachedCriteria, finalint rSm#/)4A
gQ%mVJB{(
startIndex){ 8DbP$Wwi
return findPageByCriteria Ge=\IAj
'WBhW5@
(detachedCriteria, PaginationSupport.PAGESIZE, a1[J>
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startIndex); =4U$9jo!;
} ,JTyOBB<I
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public PaginationSupport findPageByCriteria {i3=N{5b
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(final DetachedCriteria detachedCriteria, finalint w\V<6_[vv.
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pageSize, * kUb[
finalint startIndex){ 5lM 3In@
return(PaginationSupport) e eyZ$n
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getHibernateTemplate().execute(new HibernateCallback(){ gp
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publicObject doInHibernate H`Zg-j`
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(Session session)throws HibernateException { %.Kr`#lCr
Criteria criteria = 3/(eK%d4Xb
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detachedCriteria.getExecutableCriteria(session); !1]jk(Z
int totalCount = s$0dLEa9
A@4{-e\
((Integer) criteria.setProjection(Projections.rowCount JRE\R&>g
nr(C*E
()).uniqueResult()).intValue(); 0m\( @2E
criteria.setProjection HzuG- V
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(null); 9i{(GO
List items = :b_hF
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criteria.setFirstResult(startIndex).setMaxResults osLEH?iKW
qF`]}7"^
(pageSize).list(); i~M-V=Zg
PaginationSupport ps = HW'I $ .
'dv(
new PaginationSupport(items, totalCount, pageSize, s.KfMJ"u[
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startIndex); #G?",,&dM
return ps; CWB<I
} WU.eeiX
}, true); l <Z7bo
} r&:yZN
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public List findAllByCriteria(final RQ#9[6w!v
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DetachedCriteria detachedCriteria){ - ku8n%u
return(List) getHibernateTemplate yZNg[KH
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().execute(new HibernateCallback(){ 3RcnoXX_
publicObject doInHibernate Wg8*;dvtM
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(Session session)throws HibernateException { at2)%V)
Criteria criteria = ?nE9@G5Gc
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detachedCriteria.getExecutableCriteria(session); E>2AG3)
return criteria.list(); ?#nk}=;g8
} ~*~aFf5
}, true); %j{*`}
} rTJ;s
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public int getCountByCriteria(final 4Yt'I#*
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DetachedCriteria detachedCriteria){ W* n|T{n
Integer count = (Integer) /R6\_oM
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getHibernateTemplate().execute(new HibernateCallback(){ _=cuOo"!
publicObject doInHibernate 55,2eg#{O
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(Session session)throws HibernateException { mT;
Criteria criteria = XG5T`>Yl
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detachedCriteria.getExecutableCriteria(session); vo~Qo;m
return w7\
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criteria.setProjection(Projections.rowCount KmqgP`Cu
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()).uniqueResult(); ,.;{J|4P
} O
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}, true); ^.*zBrFx
return count.intValue(); 8hSw4S"$
} 7x*C`
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} p`!<yq2_
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用户在web层构造查询条件detachedCriteria,和可选的 '?3(&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uNqN &7g
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PaginationSupport的实例ps。 7$*x&We
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ps.getItems()得到已分页好的结果集 5)->.* G*
ps.getIndexes()得到分页索引的数组 X8~?uroq
ps.getTotalCount()得到总结果数 3 [O+wVv
ps.getStartIndex()当前分页索引 'S9jMyZrZ
ps.getNextIndex()下一页索引 r*FAUb`bG
ps.getPreviousIndex()上一页索引 \(zUI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 dMI G2log
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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 {qs>yQ6a:-
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一下代码重构了。 vSCJ xSt#e
8LY^>.
我把原本我的做法也提供出来供大家讨论吧: )d{fDwrx1
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首先,为了实现分页查询,我封装了一个Page类: F8\JL %
java代码: V~$?]Z %_
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/*Created on 2005-4-14*/ FB3}M)G>M
package org.flyware.util.page; Q0g^%
S2#@j#\
/** aeEio;G1
* @author Joa '<6DLtZl
* [88PCA:
*/ EbJc%%c
publicclass Page { XXXQA Y-,C
vu:] [2"0
/** imply if the page has previous page */ o,/w E
privateboolean hasPrePage; z0&Y_Up+5
,y}~rYsP%
/** imply if the page has next page */ Z
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privateboolean hasNextPage; ,Z8)DC=
\]3[Xw-$
/** the number of every page */ LYyud
privateint everyPage; .F/s(
%kP=VUXj
/** the total page number */ F><ficT
privateint totalPage; CbOCL~ "
U[Lr+nKo\
/** the number of current page */ _KZTY`/*
privateint currentPage; uSH_=^yTQ
lnK#q.]
/** the begin index of the records by the current .kB!',v\
/?V-
query */ $M$-c{>s
privateint beginIndex; I2,AT+O<
[*
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/** The default constructor */ q RRvZhf
public Page(){ VuD{t%Jb
:4r*Jju<V
} AP ]`'C
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/** construct the page by everyPage >.uIp4@(
* @param everyPage wVc^l
* */ y<c7RK]
public Page(int everyPage){ 3`Xzp
this.everyPage = everyPage; aYc^ 9*7
} !.499H3
!1Ht{cA0
/** The whole constructor */ wEQZ9?\
public Page(boolean hasPrePage, boolean hasNextPage, HumL(S'm
7"OJ,Mx%
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int everyPage, int totalPage, bL5u;iy)
int currentPage, int beginIndex){ ?.Ip(g
this.hasPrePage = hasPrePage; %l!-rXp
this.hasNextPage = hasNextPage; ZVrZkd`
this.everyPage = everyPage; fm!\**Q1
this.totalPage = totalPage; |OuIQhoE
this.currentPage = currentPage; _ER. AKY
this.beginIndex = beginIndex; `^|l+TJG
} JoD@e[(
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/** u-QHV1H`(
* @return 6MLjU1
* Returns the beginIndex. OP\L
*/ $oPc,zS-gL
publicint getBeginIndex(){ ,wngS=
return beginIndex; hoLA*v2<
} t/l<X]o
:#D~j]pP
/** Kq(JHB+
* @param beginIndex g8@F/$HY
* The beginIndex to set. 4[)tO-v:Y
*/ 7`&6l+S|
publicvoid setBeginIndex(int beginIndex){ JEF ;Q
this.beginIndex = beginIndex; x~K79Mya
} p6ryUJc6
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/** nYe:$t3F=
* @return DWN9_*{
* Returns the currentPage. ncTMcu
*/ R`B} T<*
publicint getCurrentPage(){ #w:nj1{_
return currentPage; gEw9<Y
} 0E)M6
jJ
nj1PR`AE
/** 3eB)X2~
* @param currentPage }F|B'[wn
* The currentPage to set. hE<Sm*HU
*/ EV7lgKM^
publicvoid setCurrentPage(int currentPage){ &xp]9$
this.currentPage = currentPage; ^x_$%8
} E'NS$,h
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/** }(,{^".[}
* @return h\Q@zR*0a
* Returns the everyPage. 0& ?L%Y
*/ M27H{}v
publicint getEveryPage(){ u4bVp+
return everyPage; qh6rMqq
} NK'@.=$
k|{ 4"4r
/** Ijk hV
* @param everyPage #%w)w R3
* The everyPage to set. )uMv]
*/ d8U<V<H<
publicvoid setEveryPage(int everyPage){ @4]{ZUV
this.everyPage = everyPage; %0Qq~J@Lu
} e1%kW1Z9
%?Q&a ]
/** 9ExI,
* @return 6ud<U#\b&
* Returns the hasNextPage. >0uj\5h)I]
*/ `6;$Z)=.
publicboolean getHasNextPage(){ ]2
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return hasNextPage; X4Pm&ol
} a6O <t;&
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/** `r-3"or/$
* @param hasNextPage $cU7)vmK`
* The hasNextPage to set. B2|0.G|[j
*/ Zo
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publicvoid setHasNextPage(boolean hasNextPage){ IAmZ_2
this.hasNextPage = hasNextPage; B<HN$/
} L&~' SC
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/** c((bUjS'=Y
* @return B9%%jEH*
* Returns the hasPrePage. dZI["FeO&d
*/ 67
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publicboolean getHasPrePage(){ >#Xz~xI/I
return hasPrePage; ;tF&r1
} uGm?e]7Hx<
=;E0PB_w
/** 9!kp3x/`
* @param hasPrePage 4nGt*0Er
* The hasPrePage to set. c{KJNH%7
*/ s|`wi}"x
publicvoid setHasPrePage(boolean hasPrePage){ 6>
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this.hasPrePage = hasPrePage; l(}MM|ka
} pOh<I{r1
|I29m`
/** 7(a1@V H
* @return Returns the totalPage. -GM"gkz
* hQlyqTP|2
*/ h+A+>kC5
publicint getTotalPage(){ t\TxK7i
return totalPage;
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} &fl RrJ
EU04U
/** #TC}paIpj
* @param totalPage y)a)VvU":
* The totalPage to set. =8%*Rrj^
*/ GN:|b2 "
publicvoid setTotalPage(int totalPage){ t`R{N1
this.totalPage = totalPage; ]!~?j3-k Q
} m l@%H
V|[NL4
} +|7N89l
+!!G0Zj/
"tK|/R+
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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 bN03}&I
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个PageUtil,负责对Page对象进行构造: S^|U"
java代码: dv+ZxP%g
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*?]<=IV?
/*Created on 2005-4-14*/ c b&Yf1
package org.flyware.util.page; /&_q"y9
}P-C-L{yE(
import org.apache.commons.logging.Log; {@3v$W~7M
import org.apache.commons.logging.LogFactory; E^br-{|{
';My"/
Z-
/** +6
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* @author Joa TA2ETvz^
* Cl-P6NlR".
*/ ] $r].,&
publicclass PageUtil { yT5OFD|T
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privatestaticfinal Log logger = LogFactory.getLog nk7>iK!i
0NKgtH~+
(PageUtil.class); sR[!6[AA
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/** iyd$_CJ z
* Use the origin page to create a new page N)AlQ'Lwx
* @param page !H[01
* @param totalRecords 1q3"qYH
* @return D~U RY_[A
*/ ey,f igjd.
publicstatic Page createPage(Page page, int XWQ `]m)
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totalRecords){ R!
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return createPage(page.getEveryPage(), Lo#G. s|
c@"FV,L>
page.getCurrentPage(), totalRecords); peT91b
} _ DT,iF*6
CCol>:8{P
/** JbS[(+o
* the basic page utils not including exception 19c_=$mV
&qWB\m
handler >]ZE<.
* @param everyPage P}UxA!
* @param currentPage P=KhR&gwV~
* @param totalRecords x<Gjr}
* @return page *78c2`)[
*/ m-ibS:
publicstatic Page createPage(int everyPage, int UZrEFpi
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currentPage, int totalRecords){ #+V4<o
everyPage = getEveryPage(everyPage); a:`<=^:4,
currentPage = getCurrentPage(currentPage); a$Y{ut0t(
int beginIndex = getBeginIndex(everyPage, T*PEUq
T!B\ixt6
currentPage); kWVk^,
int totalPage = getTotalPage(everyPage, EU%v
|]
cz/cY:o)
totalRecords); lS7L|
boolean hasNextPage = hasNextPage(currentPage, cNxxX!P/
4%w<Ekd
totalPage); bv'>4a
boolean hasPrePage = hasPrePage(currentPage); J -Lynvqm
r|DIf28MIq
returnnew Page(hasPrePage, hasNextPage, C=@4U}
everyPage, totalPage, (=;'>*L(
currentPage, + xO3<u
w0oTV;yh
beginIndex); CEaAtAM
} E;x-O)(&
, QWus"5H
privatestaticint getEveryPage(int everyPage){ W02z}"#
return everyPage == 0 ? 10 : everyPage; v<g=uEpN
} l~f3J$OkJ
4g8o~JI:v
privatestaticint getCurrentPage(int currentPage){ =E%@8ZbK
return currentPage == 0 ? 1 : currentPage; ,d38TN
} zIu/!aw
*jWh4F,
privatestaticint getBeginIndex(int everyPage, int f$kbb6juL
G'#u!<(^h
currentPage){ 8IQ}%|lN
return(currentPage - 1) * everyPage; +hr|$
} l!Xj UnRF
+~aIT=i3
privatestaticint getTotalPage(int everyPage, int `PL}8ydZ
f_[dFKoX
totalRecords){ u/6if9B
int totalPage = 0; 9N)I\lcY
![\P/1p
if(totalRecords % everyPage == 0) %_4#WI
totalPage = totalRecords / everyPage; [f6BA|
else aF+Lam(
totalPage = totalRecords / everyPage + 1 ; VrP{U-`
T1.U (::
return totalPage; M'<% d[
} zEtsMU
aK;OzB)
privatestaticboolean hasPrePage(int currentPage){ {}k3nJfE
return currentPage == 1 ? false : true; k?&GL!?
} EFh^C.S8
Xm>zT'B_tJ
privatestaticboolean hasNextPage(int currentPage, YW&K,)L@
OObAn^bt
int totalPage){ gjN'D!'E1D
return currentPage == totalPage || totalPage == ^@RvCJ+
g=Xy{Vm
0 ? false : true; }EkL[H!
} W}TP(~x'N
(?R!y -
M(K7xx+G
} .\ fpjQW
?{aJ#w
*nJ,|T
ou~$XZ7oi
>4Tk#+%Jj
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 DGb1_2ZQ
E] /2u3p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 .x,y[/[[)
OzrIiahz/
做法如下: u%z'.#r; a
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (XmmbAbVom
`G\Gk|4;2
的信息,和一个结果集List: 0 {z8pNrc
java代码: QJ(%rvn3
=LV-n
U!r8}@
/*Created on 2005-6-13*/ d[,Rgdd@I
package com.adt.bo; Sv /P:r
_
K'J_AMBL
import java.util.List; I@6+AU~,6
ZwLr>?0$
p
import org.flyware.util.page.Page; pMHl<HH
\zg R]|
/** eg}g}a
* @author Joa Z+y'w#MZL
*/ ph6'(,
publicclass Result { Oj _]`
/96lvn]8lO
private Page page; dV
:}
\u[}
private List content; 7AT8QC`u
R3_OCM_*
/** [.xY>\e
* The default constructor qm><}N7f
*/ s) U1U6O
public Result(){ Qe_{<E
super(); >xS({1A}
} 1-?i*C
"J+L]IC?AD
/** JZ-@za6u
* The constructor using fields I]W7FZ=o
* 7afG4
(<k
* @param page Xzg >/w
8J
* @param content vkhPE(f
*/ PaQ lQ#
public Result(Page page, List content){ grgs r_)[
this.page = page; _d3Z~cH
this.content = content; 0~RD@>]
} "%D"h
\&kj#)JYA
/** M KW~rrR
* @return Returns the content. WFahb3kx
*/ gdTW
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publicList getContent(){ ]R)wBug
return content; ZwsQ}5
} `9[n5-t
B3&C&o.h
/** ddKP3}
* @return Returns the page. o"BED!/
*/ NO[A00m|OL
public Page getPage(){ +&VY6(Zj+*
return page; m0ra
} ;y\/7E
)u{]rb[
/** T~/>U&k}J
* @param content j3-o}6
* The content to set. v"yu7tZ3N
*/ K1J |\!o
public void setContent(List content){ .tG3g:
this.content = content; +`Q]p "G
} "Tser*i )
2@Yu:|d4U
/** .lb]Xa*n
* @param page K2x2Y=
* The page to set. DVhBZ!u9
*/ q&>fKS nKs
publicvoid setPage(Page page){ q:)PfP+
this.page = page; KZ[TW,Gw
} |s/N?/qi
} lmHQ"z 3G
iy]L"7&Z2
[XI:Yf
P!f0&W
SzB<PP2
2. 编写业务逻辑接口,并实现它(UserManager, EoPvF`T
^$'z#ZN1
UserManagerImpl) auAz>6L
java代码: k;cX,*DIn
2#5Q~
s(Gs?6}>T
/*Created on 2005-7-15*/ 5[X%17&t
package com.adt.service; QObVJg,GD
02[m{a-
import net.sf.hibernate.HibernateException; :]F66dh+
WcSvw
import org.flyware.util.page.Page; Nm&'&L%Ch
PUO7Z2
import com.adt.bo.Result; OW};i|
\jk*Nm8;
/** $Q#n'#c
* @author Joa z{ eZsh
b
*/ }G{"Mp4
publicinterface UserManager { 8Pd9&/Y
:l]qTCmY
public Result listUser(Page page)throws ,^e2ma|z
,}W|cm>
HibernateException; 5SUO`4L
^wZx=kas
} \e4AxLP
Q]=/e7
m,kYE9{
VOr:G85*s
OHAU@*[lM
java代码: LYYz=oZOE!
FYFlh^}
\36 G``e
/*Created on 2005-7-15*/ u*%mUh
package com.adt.service.impl; (|AZO!
1ED7.#g
import java.util.List; %-fXa2
rlh:|#GTJ
import net.sf.hibernate.HibernateException; TDk[,4
8*b{8%<K
import org.flyware.util.page.Page; -`Z!p
import org.flyware.util.page.PageUtil; HP*{1Q@5
9C?SEbC
import com.adt.bo.Result; :+\sKEzL
import com.adt.dao.UserDAO; 4=^Ha%l
import com.adt.exception.ObjectNotFoundException; M1/(Xla3
import com.adt.service.UserManager; 93.\.&L\
]pB5cq7o
/** q,7W,<-
* @author Joa `'iO+/;GY
*/ .'66]QW
publicclass UserManagerImpl implements UserManager { ^zT=qBl
dR=sdqS#J
private UserDAO userDAO; 40
u
tmC
_(m455HZ
/** Ii}{{1N6
* @param userDAO The userDAO to set. go=xx.WJ
*/ yR{rje*
publicvoid setUserDAO(UserDAO userDAO){ ))dqC l
this.userDAO = userDAO; '$p`3Oqi
} 56kqG}mg&
iu<Tv,{8
/* (non-Javadoc) m#[c]v{
* @see com.adt.service.UserManager#listUser LrO[l0#'Q
B+Qo{-
(org.flyware.util.page.Page) !.# g
*/ ]vR
Ol.
public Result listUser(Page page)throws ex~"M&^
}U>K>"AZl
HibernateException, ObjectNotFoundException { }@
U}c6/
int totalRecords = userDAO.getUserCount(); ;s$4/b/~
if(totalRecords == 0) /#{~aCOi)
throw new ObjectNotFoundException qB@N|Bb
$;=^|I4E
("userNotExist"); ktfxb<%
page = PageUtil.createPage(page, totalRecords); J3 oUtu
List users = userDAO.getUserByPage(page); Ux^ue9
returnnew Result(page, users); wpN [0^M-0
} zobFUFx
P}Mu|AEG
} cr0/.Zv)
WN|_IJR~
WRbdv{1E
p"6[ S
lBG=jOS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xa_ IdkV
wO!>kc<
询,接下来编写UserDAO的代码: Av n-Ug
3. UserDAO 和 UserDAOImpl: ]==7P;_-
java代码: K~-V([tWg
2 7dS.6
v;z8g^L
/*Created on 2005-7-15*/ (aJ$1bT=T
package com.adt.dao; :rufnmsP<U
0wqw5KC
import java.util.List; s+ *LVfau
mV"F<G; H
import org.flyware.util.page.Page; r&v!2A]:
<x<qO=lq
import net.sf.hibernate.HibernateException; J<"Z6 '0v
t6e6v=.Pg
/** Y/m-EL
* @author Joa )iIsnM
*/ t vW0 W
publicinterface UserDAO extends BaseDAO { \jZmu
p[|V7K'Z
publicList getUserByName(String name)throws >#S}J LZ
7|Wst)_~j
HibernateException; ]3]B$
.8'uIA{_2
publicint getUserCount()throws HibernateException; 32j#kJ W
9ec#'i=
publicList getUserByPage(Page page)throws 753gcY#i
_a$5"
HibernateException; pox;NdX7
Wo9=cYC)
} ia.+<,
$`S
YGyw^$.w
-`spu)
fK(:vwh
j)Q}5M
java代码: * >NML]#0
{=!BzNMj
^^uY)AL
/*Created on 2005-7-15*/ 6P(jc
package com.adt.dao.impl; ) .V,zmI
X?r$o>db
import java.util.List; e&(Wn2)o
KF#qz2S
import org.flyware.util.page.Page; MdkL_YP}.
1"<{_&d1
import net.sf.hibernate.HibernateException; meap ;p
import net.sf.hibernate.Query; S n~P1C
9zBt
a
import com.adt.dao.UserDAO; g[ @Q iy
D7thLqA
/** ei]Q<vT6
* @author Joa h6`VU`pPI
*/ I&1.}{G>F
public class UserDAOImpl extends BaseDAOHibernateImpl i(# Fjp
R5},E
implements UserDAO { O#8lJ%?
X,8Zn06M
/* (non-Javadoc) _-v$fDrz
* @see com.adt.dao.UserDAO#getUserByName SBi4i;qD
:<
]sJfN
(java.lang.String) a9 S&n5
*/ TEK#AR
publicList getUserByName(String name)throws //$^~}wt
6|6O|
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HibernateException { tB}W
)Eb
String querySentence = "FROM user in class Ms%C:KG
%f&Bt,xEo
com.adt.po.User WHERE user.name=:name"; t08[3Q&
Query query = getSession().createQuery aiw4J
@@!]Raj=
(querySentence);
{pRa%DF
query.setParameter("name", name); c~\^C_
return query.list(); ST0|2)Lh"
} iP^[xB~v
%N7G>_+
/* (non-Javadoc) ady
SwB
* @see com.adt.dao.UserDAO#getUserCount() 7=wQ#bq"1P
*/ #aP;a-Q|k
publicint getUserCount()throws HibernateException { #7J3,EV
int count = 0; 0o.h{BN
String querySentence = "SELECT count(*) FROM p .~5k
`Y '-2Fv
user in class com.adt.po.User"; %3K'[2F
Query query = getSession().createQuery ?IO3w{fmH
>;xkiO>Y
(querySentence); !0X"^VB
count = ((Integer)query.iterate().next K_X(j$2Xc
eNFA.*p<
()).intValue(); 85FzIX-F%
return count; ^(qR({cX
} BSEP*#s
Bq,Pk5b
/* (non-Javadoc) 3[kl` *`
* @see com.adt.dao.UserDAO#getUserByPage ZGd7e.u=
#g
Rns
(org.flyware.util.page.Page) rO,n~|YJ
*/ 7B)@ aUj$
publicList getUserByPage(Page page)throws b%j4W)Z
uy=<n5`oNG
HibernateException { 6k1_dRu
String querySentence = "FROM user in class $yFR{_]
> 3l3
com.adt.po.User"; (Y?}'?
Query query = getSession().createQuery w/fiNY5FZ
LA,G>#?H
(querySentence); Q#4OgNt
query.setFirstResult(page.getBeginIndex()) eoiC.$~\
.setMaxResults(page.getEveryPage()); /cD]m
return query.list(); w*4sT+
P
} g*%o%Lv
QP6a,^];
} #t">tL
H"V)dEm
Aacj?
lI[O!VuKc
vrsOA@ee3H
至此,一个完整的分页程序完成。前台的只需要调用 pD6a+B\;k
'&y+,2?;Y[
userManager.listUser(page)即可得到一个Page对象和结果集对象 rAu@`H?
?)/H8n
的综合体,而传入的参数page对象则可以由前台传入,如果用 }M(XHw
yjChnp
Cc
webwork,甚至可以直接在配置文件中指定。 zhACNz4tJ
7(zY:9|(
下面给出一个webwork调用示例: SciEHI#
java代码: "3a_C,\
~uO9>(?D
m\|ie8
/*Created on 2005-6-17*/ RLF]Wa,
package com.adt.action.user; be&,V_F
p-%m/d?
import java.util.List; uo^tND4a;j
!ma'*X
import org.apache.commons.logging.Log; ]~m2#g%
import org.apache.commons.logging.LogFactory; !~f!O"n)3r
import org.flyware.util.page.Page; M7AUY#)
::k/hP9.^
import com.adt.bo.Result; sHMZ'9b
import com.adt.service.UserService; H|B4.z
import com.opensymphony.xwork.Action; :YN,cI d*
%R*-oQ1T
/** yLCJSN$7
* @author Joa 9jt+PII
*/ =MMSmu5!
publicclass ListUser implementsAction{ <o_(,,P%
:#spL*FIx
privatestaticfinal Log logger = LogFactory.getLog h@(S];.
\&X*-T[]j
(ListUser.class); E#+|.0*!s
+C9l7 q
private UserService userService; G(7WUMjl
oyo
V1jO
private Page page; Z|$OPMLX
}JBLzk5|
privateList users; +S}/6dg
^y&sKO
/* 1bJrEXHXy
* (non-Javadoc) #ZpR.$`k
* 7-MkfWH2b6
* @see com.opensymphony.xwork.Action#execute() AU^5N3%j
*/ !qVnziE,,
publicString execute()throwsException{ SH M@H93
Result result = userService.listUser(page); $r=tOD4;
page = result.getPage(); /%T d(
users = result.getContent(); .t|B6n!
return SUCCESS; VpmD1YSn
} '"Y(2grP
CN<EgNt1kN
/** i@#fyU)[G
* @return Returns the page. $"]*,=-X
*/ AtW<e;!0te
public Page getPage(){ W%^;:YQ9i
return page; :/'oh]T|
} +HNM$yp
\ POQeZ
/** <;nhb
* @return Returns the users. [&a=vE
*/ YhNO{4D
publicList getUsers(){ vmK`QPu2
return users; $[DSe~
} l^%W/b>?b
K';x2ffj
/** *b+~@o
* @param page eww/tG a
* The page to set. "Z*u2_ H
*/ /p_#8}Uh
publicvoid setPage(Page page){ E*X-f"
this.page = page; U/3<p8
} El#"vIg(\
H|*Ual
/** rc+}KO
* @param users -yP_S~\n
* The users to set. %T'<vw0
*/ 6E@qZvQ
publicvoid setUsers(List users){ &a
bR}J[
this.users = users; }IGoPCV|
} VgyY7INx9
<mX EX`?
/** xl4 A<
* @param userService Pmj%QhOYE
* The userService to set. +1=]93gP
*/ 2Bg0
M
publicvoid setUserService(UserService userService){ Y]6kA5
this.userService = userService; `PApmS~}
.
} Vmf!0-
} !omf>CW;ud
0JM`*f%n
p?XVO#
(N
:vDq'
c}r"O8M
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ;o-c.-!F
T1_>qnSz
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 M=Cl|
=/SBZLR(9
么只需要: ]XhX aoqL
java代码: wY6m^g$h3
38l 8n.
kx31g,cf]w
<?xml version="1.0"?> 'sT7t&v~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork EwKFT
FL
K@>($BX]
1.0//EN" "http://www.opensymphony.com/xwork/xwork- aT"0tn^LO
H4"'&A7$
1.0.dtd"> ft><Ql3
c1aIZ
<xwork> [h[@?8vB
urK~]68
<package name="user" extends="webwork- AMf{E
Z(:q.{"r
interceptors"> {k8R6l1
~D\zz }l
<!-- The default interceptor stack name VBv|7S
e
.1!
K
--> *BFG{P
<default-interceptor-ref PEDV9u[A
>PmnR>x-rj
name="myDefaultWebStack"/> S";c7s
&f($= 68
<action name="listUser" !THa?U;
c%@<
h6
class="com.adt.action.user.ListUser"> Ssg1p#0J
<param bAS/cuZs
Jy?; <
name="page.everyPage">10</param> }^tW's8
<result B3g#)
<e'/z3TbRW
name="success">/user/user_list.jsp</result> L-eO_tTh0
</action> <@H`5[R
{u)>W@Lr
</package> SS*3Qx:[
Ci(c`1av
</xwork> ( we)0AxF'
;fe~PPT
mr2fNA>kR
dwJnPJ=z
</]a`h]
#sM`>KG6T1
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 uF<}zFS
x@#aOf4<U
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 zw[ #B #
as3*49^9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;:obg/;uJ
Tnoy#w}Ve
H[2W(q6
%Hu?syo
AjD?_DPc
我写的一个用于分页的类,用了泛型了,hoho ,s`4k?y
4@r76v}{
java代码: #Oi{7~
w8}jmpnI
)m_q2xV
package com.intokr.util; |'qvq/#^
wQX18aF/#d
import java.util.List; ~CuJ$(9Y
R4vf
/** YHzP/&0
* 用于分页的类<br> U%)-_
*`z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> (lg~}Jwq
* ~@mNR^W-W
* @version 0.01 1+9!W
* @author cheng ]FEDAGu
*/ }'`}| pM$
public class Paginator<E> { oy\U\#k
privateint count = 0; // 总记录数 .<4U2h
privateint p = 1; // 页编号 Qz4Do6#y
privateint num = 20; // 每页的记录数 yb6gYN
privateList<E> results = null; // 结果 %l[]n;*$
sA2esA@C<o
/** W:>XXUU
* 结果总数 uj:1_&g
*/ -% \LW1
publicint getCount(){ 0K4A0s_R`
return count; TeRH@oI
} _$_,r H
,H>'1~q
publicvoid setCount(int count){ *$Y_ %}
this.count = count; #'dNSez5
} ]Z?jo#F
.z[#j]k
/** y({lE3P
* 本结果所在的页码,从1开始 EV@yJ]
* I,W`s
* @return Returns the pageNo. qSt\ 6~
*/ -ImVXy]?
publicint getP(){ (_]D\g~
return p; f4Ob4ah!(
} %UlgG1?A
:. u2^*<
/** G=er0(7<
* if(p<=0) p=1 RFPcH8-u7
* c#-*]6x
* @param p
&H[7UyC
*/ _Kbj?j
publicvoid setP(int p){ >XxHp
if(p <= 0) @r=,:
'Mt
p = 1; KM?w{ ~9
this.p = p; 1zgM$p
} m48Ab`
re4A5Ev$
/** $18?Q+?3
* 每页记录数量 \5}*;O@
*/ 4~1lP&
publicint getNum(){ U/-k'6=M
return num; ~OWpk)Vq
} |K" nSXzk
DMOP*;Uk
/** UF$O@l
* if(num<1) num=1 "7eL&
*/ g7{:F\S
publicvoid setNum(int num){ dQ_hlx!J
if(num < 1) (|>rDk;
num = 1; -A@/cS%p
this.num = num; l6zYiM
} 1Tr%lO5?6
=RAojoN
/** ^B1$|C
D,
* 获得总页数 >pp#>{}
*/ NFF!g]QN
publicint getPageNum(){ Z/T(4
return(count - 1) / num + 1; tSe[*V4{'
}
XRHngW_A
uPxJwWXO
/**
vR&b2G7o
* 获得本页的开始编号,为 (p-1)*num+1 !#zO%
*/ ZQ>Q=eCs 1
publicint getStart(){ 3 .K #,
return(p - 1) * num + 1; B#?rW*yEe
} 'S|7<<>4k
+,cd$,18
/** ra2{8 x
* @return Returns the results. zI\+]U'
*/ U9K'O !i>
publicList<E> getResults(){ 4)8e0L*[B?
return results; HYL['B?Wid
} 8/T,{J\
SSq4KFO1
public void setResults(List<E> results){ 4Y1dkg1y
this.results = results; ZtmaV27s/
} 'Yi="kno
!^o{}*]Pi
public String toString(){ 56MY@
StringBuilder buff = new StringBuilder YrYmPSb=
|QD#Dx1_
(); ;+.cD
buff.append("{"); c3 )jsf
buff.append("count:").append(count); iXq*EZb"R
buff.append(",p:").append(p); *Q)-"]O(k
buff.append(",nump:").append(num); %'X~9Pvi
buff.append(",results:").append :K 5?&kT
wWSo+40
(results); 1xu~@v60
buff.append("}"); ]s!id[j
return buff.toString(); 94^b"hU
} 8]oolA:^4s
"0,FB4L[U5
} c2Exga_
mHV{9J
R:3=!zav