Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5AFJC?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ROH|PKb7
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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 IPS4C[v
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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 C7]f*TSC4
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。 ~nmoz/L
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分页支持类: aC]$k'71
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java代码: LQ@"Xe]5
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package com.javaeye.common.util; 0CHH)Bku
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import java.util.List; Akq2 d;
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publicclass PaginationSupport { /!0={G
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publicfinalstaticint PAGESIZE = 30; {a =#B)6
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privateint pageSize = PAGESIZE; ld[I}88$
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privateList items; a1T'x~ '
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privateint totalCount; #$.;'#u'so
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privateint[] indexes = newint[0]; CXH&U@57{
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privateint startIndex = 0; ?e%ZOI
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public PaginationSupport(List items, int 1y:-N6
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totalCount){ i}cRi&2[
setPageSize(PAGESIZE); B`EJb71^Xy
setTotalCount(totalCount); 9=s<Ld
setItems(items); &5>Kl}7
setStartIndex(0); "fb[23g%@k
} rjK%t|aV^
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public PaginationSupport(List items, int @JGP,445
49eD1h3'X[
totalCount, int startIndex){ |44Ploz2b
setPageSize(PAGESIZE); |NlO7aQ>2H
setTotalCount(totalCount); ~?l |
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setItems(items); +V2F#fI/
setStartIndex(startIndex); \UA[
} (|2t#'m
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public PaginationSupport(List items, int B.=FSow
[:dY0r+
totalCount, int pageSize, int startIndex){ pd?Mf=>#
setPageSize(pageSize); G0Iw-vf
setTotalCount(totalCount); )Om*@;r(
setItems(items); Ao 'l"-
setStartIndex(startIndex); P1!qbFDv8
} )705V|v
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publicList getItems(){ X;$+,&M"
return items; \$K20)
} 5%"V[lDx@
;[ZEDF5H
publicvoid setItems(List items){ j;zM{qu_
this.items = items; /l3V3B7
} 7^avpf)>
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publicint getPageSize(){ hDDn,uzpd
return pageSize; I^.Om])
} O2V
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publicvoid setPageSize(int pageSize){ poE0{HOU
this.pageSize = pageSize; ~g91Pr
} #<fRE"v:Q
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publicint getTotalCount(){ cZ,b?I"Q%
return totalCount; wLIMv3;k
} soxc0OlN
yxPazz
publicvoid setTotalCount(int totalCount){ 2Ah#<k-gC;
if(totalCount > 0){ {p2!|A&a
this.totalCount = totalCount; l$KA)xbI
int count = totalCount / t9lPb_70
FaAC&F@u
pageSize; MpT8" /.]A
if(totalCount % pageSize > 0) Q0sI(V#
count++; hgG9m[?K
indexes = newint[count]; :
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for(int i = 0; i < count; i++){ 8S
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indexes = pageSize * "x0^#AVg
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i; z(O Nv#}p
} [jQp~&nY
}else{ &u."A3(
this.totalCount = 0; CO/]wS
} `v!urE/gg%
} %@b0[ZC
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publicint[] getIndexes(){ ]h`&&B qt
return indexes; LENq_@$
} bIDj[-CDG
P}}* Q7P
publicvoid setIndexes(int[] indexes){ l:~/<`o
this.indexes = indexes; J3V=
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} fUWG*o9
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publicint getStartIndex(){ h8q[1"a:
return startIndex; dlh)gp;
} ,&A7iO
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publicvoid setStartIndex(int startIndex){ 6yG^p]zZ
if(totalCount <= 0) g{)dP!}
this.startIndex = 0; ^LnTOdAE
elseif(startIndex >= totalCount) B3`5O[6
this.startIndex = indexes {lzWrUGO
gx/,)> E.
[indexes.length - 1]; =ZznFVJ`={
elseif(startIndex < 0) dES"@?!^
this.startIndex = 0; Evq IcZ
else{
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this.startIndex = indexes y-b%T|p9
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[startIndex / pageSize]; n+9=1Oo"
} ?=msH=N<l
} ! I:%0D
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publicint getNextIndex(){ Dj?> <@
int nextIndex = getStartIndex() + HyQJXw?A:
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pageSize; R%WCH?B<}
if(nextIndex >= totalCount) 3pROf#M
return getStartIndex(); a.\:T,cP>
else Z clQ
return nextIndex; Ml{,
} u~:y\/Y6
^Z+?h&%%
publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - ?=7cF
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pageSize; iuW[`ouX
if(previousIndex < 0) #Vt%@*
i
return0; O63<AY@
else | j`@eF/"
return previousIndex; 1=c\Rr9]
} e]"W!KcD9
#G|RnV%t$~
} `AtBtjs RV
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抽象业务类 sf
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java代码: ,kGc]{'W
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/** wu!59pL
* Created on 2005-7-12 iN\4gQ!
*/ Yui3+}Ms
package com.javaeye.common.business; 85$m[+md
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import java.io.Serializable; ~"H,/m%2o
import java.util.List; TDKki(o=~
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import org.hibernate.Criteria; ]=I@1B;_m
import org.hibernate.HibernateException; k68T`Ub\W6
import org.hibernate.Session; z&)A,ryW0
import org.hibernate.criterion.DetachedCriteria; 29"'K.r
import org.hibernate.criterion.Projections; WIT>!|w_
import m+R[#GE8#
hGe/;@%
org.springframework.orm.hibernate3.HibernateCallback; BWa,f8
import ?0?#U0(;u
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org.springframework.orm.hibernate3.support.HibernateDaoS =F~S?y
<n];mfh1
upport; .-c4wm}
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import com.javaeye.common.util.PaginationSupport; *boR`[Ond
ay
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public abstract class AbstractManager extends 1\~ "VF*{
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HibernateDaoSupport { EStB#V^
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privateboolean cacheQueries = false; 2!m/
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privateString queryCacheRegion; DDP/DD;n}r
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publicvoid setCacheQueries(boolean :Zbg9`d*
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cacheQueries){ '(f* 2eE:
this.cacheQueries = cacheQueries; kR-SE5`Jk
} { ]{/t-=
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publicvoid setQueryCacheRegion(String 4{U T!WIi
v5#jZ$<F
queryCacheRegion){ x7&B$.>3
this.queryCacheRegion = qZtzO2Mt
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queryCacheRegion; v\gLWq'
} {j?FNOJn
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publicvoid save(finalObject entity){ DFB@O|JL
getHibernateTemplate().save(entity); -hGk?_Nqa/
} M#4pE_G
.\ULbN3Z
publicvoid persist(finalObject entity){ XFHYQ2ME2
getHibernateTemplate().save(entity); S]e|"n~@
} [I,Z2G,Jb
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publicvoid update(finalObject entity){ _ @NL;w:!
getHibernateTemplate().update(entity); o4F2%0gJ
} y1eWpPJa
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publicvoid delete(finalObject entity){ oi&VgnSk
getHibernateTemplate().delete(entity); bQg:zww
} y*jp79G
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publicObject load(finalClass entity, UJAv`yjG
)1J R#
finalSerializable id){ Fx_z 6a
return getHibernateTemplate().load >reU#j
by1<[$8r
(entity, id); Y1W1=Uc uk
} {yTGAf-DV
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publicObject get(finalClass entity, TTX5EDCrC
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finalSerializable id){ T"}5}6rSG
return getHibernateTemplate().get mUAi4N
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(entity, id); Tj`,Z5vy
} x/I%2F
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publicList findAll(finalClass entity){ Af~$TyX
return getHibernateTemplate().find("from ~|DUt
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" + entity.getName()); >UTBO|95y
} Wq D4YGN
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publicList findByNamedQuery(finalString Z!a=dnwHz
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namedQuery){ hn7#
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return getHibernateTemplate U/66L+1
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().findByNamedQuery(namedQuery); e }?db
} 3)t.p>VgO
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publicList findByNamedQuery(finalString query, Q",t3i4
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finalObject parameter){ o=:9y-nH
return getHibernateTemplate '2A)}uR
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().findByNamedQuery(query, parameter); 0I-9nuw,^;
} b"<liGh"n-
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publicList findByNamedQuery(finalString query, */5d>04
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finalObject[] parameters){ :;%2BSgFU
return getHibernateTemplate y1jCg%'H
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().findByNamedQuery(query, parameters); <yV"6/l0
} XAD- 'i
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publicList find(finalString query){ H`XUJh
return getHibernateTemplate().find ]\-A;}\e
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(query); Y Vt% 0
} h"B+hu
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publicList find(finalString query, finalObject k&M;,e3v6
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parameter){ +qN>.y!Y
return getHibernateTemplate().find r5S[-`s;
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(query, parameter); ^ox=HNV
} j.[.1G*("
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public PaginationSupport findPageByCriteria d(ZO6Nr Q
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(final DetachedCriteria detachedCriteria){ ^x ]r`b
return findPageByCriteria :I] Mps<
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); !NK1MU?T)
} ~Py`P'+
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public PaginationSupport findPageByCriteria A7{\</Z
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(final DetachedCriteria detachedCriteria, finalint L?b~k=
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startIndex){ Qab>|eSm
return findPageByCriteria ^do9*YejX;
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(detachedCriteria, PaginationSupport.PAGESIZE, /s&9SYF
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startIndex); VcE:G#]5
} @Rze|
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public PaginationSupport findPageByCriteria *uRBzO}
)th<,Lo3#
(final DetachedCriteria detachedCriteria, finalint @}u*|P*
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pageSize, FW;?s+Uyx
finalint startIndex){ <Xhm`rH
return(PaginationSupport) sjHE/qmq-Z
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate #6aW9GO
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(Session session)throws HibernateException { yf.~XUk^
Criteria criteria = sRR(`0Zp
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detachedCriteria.getExecutableCriteria(session); 8}x:`vDK
int totalCount = V*;(kEqj
ij`w} V
((Integer) criteria.setProjection(Projections.rowCount wo{gG?B
%g$o/A$
()).uniqueResult()).intValue(); vkV0On
criteria.setProjection LKB$,pR~1l
nsC3
(null); /N10
List items = x_Y!5yg
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criteria.setFirstResult(startIndex).setMaxResults oG?Xk%7&\
_Kf% \xg
(pageSize).list(); 3AtGy'NTp
PaginationSupport ps = q-2Bt,Y
rl;~pO5R9
new PaginationSupport(items, totalCount, pageSize, yjX9oxhtL
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startIndex); A2Ed0|B y
return ps; z (wc0I
} 3BJ0S.TF
}, true); ibk6|pp
} >Eto(
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public List findAllByCriteria(final ;?iW%:_,
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DetachedCriteria detachedCriteria){ Np9<:GF1
return(List) getHibernateTemplate lIS-4QX1
&)ChQZA
().execute(new HibernateCallback(){ L|xbR#v
publicObject doInHibernate {rw|# Z>A
;bib/
(Session session)throws HibernateException { .@U@xRu7|
Criteria criteria = \'D0'\:vz
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detachedCriteria.getExecutableCriteria(session); =s2*H8]
return criteria.list(); q"J]%zO
} HCs?iJ
}, true); WPMSm<[
} KL57#gV
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public int getCountByCriteria(final E
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DetachedCriteria detachedCriteria){ W+?4jwqw
Integer count = (Integer) #rfiD%c
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getHibernateTemplate().execute(new HibernateCallback(){ 3$>1FoSk
publicObject doInHibernate 9IfmW^0
z E9W8:7
(Session session)throws HibernateException { SsDmoEeB[
Criteria criteria = MaQqs=
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detachedCriteria.getExecutableCriteria(session); G@X% +$I
return 9-a0 :bP
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criteria.setProjection(Projections.rowCount ,j_i?Ff
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0t
()).uniqueResult(); T_5H&;a
} eJX9_6m-
}, true); aSQ#k;T[
return count.intValue(); @:vwb\azVD
} DA,?}
} 0znR0%~
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用户在web层构造查询条件detachedCriteria,和可选的 flbd0NB
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Wt-GjxGi
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PaginationSupport的实例ps。 iz PDd{[
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ps.getItems()得到已分页好的结果集 K
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ps.getIndexes()得到分页索引的数组 n 0L^e
ps.getTotalCount()得到总结果数 /7F:T[
ps.getStartIndex()当前分页索引 _Q 4)X)F
ps.getNextIndex()下一页索引 dcN22A3
ps.getPreviousIndex()上一页索引 7[XRd9a5(
=-n}[Y}A
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 S_UIO.K
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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 c<Tf
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;iL#7NG-R
一下代码重构了。 ]Q)OL
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我把原本我的做法也提供出来供大家讨论吧: <R=Zs[9M1
M%P:n/j
首先,为了实现分页查询,我封装了一个Page类: h
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java代码: .4!=p*Y
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/*Created on 2005-4-14*/ _F|Ek ;y%
package org.flyware.util.page; [/41%B2
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/** ~U&AI1t+J
* @author Joa ope^~+c~\
* ;+hH
*/ k=T\\]KxC
publicclass Page { M@v.c;Lt
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/** imply if the page has previous page */ i2SR{e8:GF
privateboolean hasPrePage; '3^'B03
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/** imply if the page has next page */ a~y'RyA
privateboolean hasNextPage; Y\g3hM
vy:Z /1q
/** the number of every page */ LsU9 .
privateint everyPage; Fd9[pU
<*cikXS
/** the total page number */ {9.|2%a
privateint totalPage; Wt~BU.
'YSHi\z ](
/** the number of current page */ _L=h0H l
privateint currentPage; q9s=~d7
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/** the begin index of the records by the current ' %o#q6O
<x>Mo
query */ ds[|
privateint beginIndex; cTT L1SW
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/** The default constructor */ z*%q@]ym
public Page(){ -m~#Bq
D2~*&'4y
} amY!qg0P*
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/** construct the page by everyPage u.xnO cOH!
* @param everyPage 'm
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* */ oW6XF-yM
public Page(int everyPage){ ]Er$*7f
this.everyPage = everyPage; H$UcF1k<
} z!9-:
/f;~X"!
/** The whole constructor */ >tW#/\x{
public Page(boolean hasPrePage, boolean hasNextPage, ePo}y])2
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int everyPage, int totalPage, : eVq#3}
int currentPage, int beginIndex){ =Jb>x#Y
this.hasPrePage = hasPrePage; QhJiB%M
this.hasNextPage = hasNextPage; P+/e2Y
this.everyPage = everyPage; Mb~F%_
this.totalPage = totalPage; z-)O9PV
this.currentPage = currentPage; \
}G>8^
this.beginIndex = beginIndex; 20Wg=p9L
} _xhax+,! ~
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/** 5$C-9
* @return f%}xO+.s
* Returns the beginIndex. Ds:'Lb
*/ ?$4 PVI}
publicint getBeginIndex(){ Er?&Y,o
return beginIndex; tY4;F\e2|A
} Qzw;i8n{
P~X2^bw
/**
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* @param beginIndex )lDD\J7
* The beginIndex to set. t"oeQ*d%
*/ R (n2A$
publicvoid setBeginIndex(int beginIndex){ 13x p_j
this.beginIndex = beginIndex; /cP"h!P}~~
} m ~$v;?i
3/eca
/** -zfR)(zG
* @return ]:J$w]\
* Returns the currentPage. - 1gVeT&
*/ K[zVa
publicint getCurrentPage(){ O0H.C0}
return currentPage; {E|$8)58i
} SOA,kwHRe
:gFx{*xN/9
/** ;Q`lNFa
* @param currentPage DkDmE
* The currentPage to set. $6R-5oQ
*/ 4;2uW#dG"
publicvoid setCurrentPage(int currentPage){ [j+sC*
this.currentPage = currentPage; O5BYD=7
} gw<q.XL
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/** Y(Hs #Kn{
* @return *.w9c
* Returns the everyPage. iuul7VR-%
*/ 44j*KsBf
publicint getEveryPage(){ <t!W5q
return everyPage; h^P#{W!e\
} 5146kp|1
XfIJ4ZM5
/** ]\HvK CN}
* @param everyPage @d1Q"9}B
* The everyPage to set. ":N9(}9
*/ 4Ftu
publicvoid setEveryPage(int everyPage){ C~exi[3
this.everyPage = everyPage; MVUJD{X#
} p!AAFmc
sU^1wB
Rj
/** [0("Q;Ec[j
* @return w5 Li&m
* Returns the hasNextPage. +:/%3}`
*/ :7;@ZEe
publicboolean getHasNextPage(){ H3oFORh
return hasNextPage; P16~Qj
} VuZr:-K/
-yNlyHv9
/** _7y[B&g[r
* @param hasNextPage YtLt*Ig%
* The hasNextPage to set. +&H4m=D-#a
*/ ?:9"X$XR
publicvoid setHasNextPage(boolean hasNextPage){ 8zq=N#x
this.hasNextPage = hasNextPage; *|HY>U.
} )0k53-h&
Lu%b9Jk
/** _DEjF)S
* @return z` b,h\
* Returns the hasPrePage. 7F.4Ga;
*/ %A0/1{(
publicboolean getHasPrePage(){ ql~J8G9
return hasPrePage; u_Z+;{]Pj
} e&>2
n
F_P~x(X
/** 3o/[t
* @param hasPrePage :[d9tm
* The hasPrePage to set. b|(:[nB
*/ |JsZJ9W+J
publicvoid setHasPrePage(boolean hasPrePage){ _,*r_D61S
this.hasPrePage = hasPrePage; KqP#6^ _
} )=(kBWM
M869MDo
/** *qpSXmOz
* @return Returns the totalPage. M )(DZ}
* "$vRMpW:
*/ b\,+f n
publicint getTotalPage(){ ?Z} &EH
return totalPage; EKN~H$.
} j5h-dK
JK]PRDyD
/** %@Jsal'
* @param totalPage MnHNjsO#
* The totalPage to set. ue>D7\8
*/ /g.U&oI]D
publicvoid setTotalPage(int totalPage){ ksm~<;td
this.totalPage = totalPage; ,`sv1xwd
} iN.n8MN=I
$<OD31T
} tQ601H>o
!H\F2Vxs
~F#j#n(=`q
^=*;X;7
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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 0tJZ4(0
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个PageUtil,负责对Page对象进行构造: BFt> 9x]T
java代码: o#N+Y?O
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/*Created on 2005-4-14*/ f?)-}\[IR{
package org.flyware.util.page; @E8+C8'
>.D4co>
import org.apache.commons.logging.Log; u]G\H!WkQ
import org.apache.commons.logging.LogFactory; 3iU=c&P
Qv ?"b
/** #s9aI_
* @author Joa <{cQ2
* CNx8]
_2
*/ e~(5%CO>#j
publicclass PageUtil { -7|H}!DFT
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privatestaticfinal Log logger = LogFactory.getLog 7PF%76TO
51.%;aY~z
(PageUtil.class); 5E
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/** /Gfw8g\}
* Use the origin page to create a new page q0\6F^;M
* @param page lr$zHI7_`
* @param totalRecords N)Z?Z+}h
* @return EBmt9S
*/ nT)vNWT=
publicstatic Page createPage(Page page, int 8JUwf
m)D|l1AtF
totalRecords){ |+"(L#wk
return createPage(page.getEveryPage(), t3^&;&[
U`s{Jm
page.getCurrentPage(), totalRecords); 3= ;<$+I6
} HLi%%"'
7o}J%z
/** JjS?
* the basic page utils not including exception cl/_JQ&
hFBe,'3M
handler ]}X
* @param everyPage Vf1^4t
* @param currentPage Dum9lj
* @param totalRecords N4HqLh23H
* @return page @|T'0_'
*/ Z$? #
publicstatic Page createPage(int everyPage, int PmM3]xVzd
2b8L\$1q
currentPage, int totalRecords){ QSf|nNT
everyPage = getEveryPage(everyPage); +qdEq_m
currentPage = getCurrentPage(currentPage); 3T0"" !Q
int beginIndex = getBeginIndex(everyPage, f|oh.z_R
f`66h M[
currentPage); 9(<@O%YU
int totalPage = getTotalPage(everyPage, Yu`~U,m
r:TH]hs12+
totalRecords); wwcBsJ1{
boolean hasNextPage = hasNextPage(currentPage, ^LzF@{ G
_h1mF<\ X^
totalPage); 7 Fsay+a
boolean hasPrePage = hasPrePage(currentPage); @9|hMo
]
@fk] ]R
returnnew Page(hasPrePage, hasNextPage, |(^PS8wG
everyPage, totalPage, 11;zNjD|
currentPage, @`Su0W+.
r#mx~OVkk
beginIndex); -`6+UkOV[x
} P0jtp7)7
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privatestaticint getEveryPage(int everyPage){ ~WV"SaA)*U
return everyPage == 0 ? 10 : everyPage; hehFEyx
} [z9Z5sLO
'@P^0+B!(.
privatestaticint getCurrentPage(int currentPage){ y1L,0 ]
return currentPage == 0 ? 1 : currentPage; 7"D.L-H
} )@bQu~Y
#:%/(j
privatestaticint getBeginIndex(int everyPage, int x'R`.
!g3
lks!w/yCF
currentPage){ 8, >P
return(currentPage - 1) * everyPage; d m%8K6|
} ;i:d+!3XwC
RViuJ;
privatestaticint getTotalPage(int everyPage, int }*"p?L^p{
Kx JqbLUC
totalRecords){ %H"47ZFxAs
int totalPage = 0; L_iFt!
7. ;3e@s
if(totalRecords % everyPage == 0) y"wShAR
totalPage = totalRecords / everyPage; Pk)1WK7E
else QP J4~
totalPage = totalRecords / everyPage + 1 ; \dQNLLg/
J5jvouR
return totalPage; K",N!koj
} r]36zX v
k"w"hg&e
privatestaticboolean hasPrePage(int currentPage){ k|d+#u[Mj@
return currentPage == 1 ? false : true; $* Kvc$D
} wLr_-vJ
wq `Bd
privatestaticboolean hasNextPage(int currentPage, }RqK84K
>[*qf9$
int totalPage){ bA->{OPkT
return currentPage == totalPage || totalPage == x-3\Ls[I
/&94 eC
0 ? false : true; sD wqH.L
} i
K? w6
Pgea NK5Y
cYt!n5w~W
} 6!FQzFCZq
VP]% Hni]
I~XSn>-H
S{m%H{A!
Th%Sjgsn
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。 y'*K|aTG
|Xy6PN8
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 4{`{WI{
=rX>.P%Q 5
做法如下: #;nYg?d=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 '`KY!]L
XpJ7o=?W3
的信息,和一个结果集List: n?Nt6U
java代码: 92KRb;c
}`~+]9<
|
%Vh`HT
/*Created on 2005-6-13*/ XOS[No~
package com.adt.bo; @MCg%Afw
g}',(tPMZ
import java.util.List; K(Bf2Mfq
tZG:Pr1U@
import org.flyware.util.page.Page; z' >_Mc6
n6a`;0f[R
/** HC,Se.VYS
* @author Joa E~oOKQ5W
*/ pIX`MlBdF
publicclass Result { ?(i{y~
*!7O~yQ
private Page page; d-dEQKI?;
N<injx
private List content; e**qF=HCw
[HZv8HU|
/** 6,{$J
* The default constructor 0KOgw*>_
*/ /s}}&u/
public Result(){ G<v&4/\p`M
super(); ~M4;
} ,nDaqQ-C!!
yaH
Zt`Y
/** YcpoL@ab
* The constructor using fields rh}J3S5vp
* gSQJJxZ{?
* @param page j eP
* @param content >V}#[ /n
*/ `RL"AH:+
public Result(Page page, List content){ j#q-^h3H
this.page = page;
Z>5b;8
this.content = content; pg)WKbV
} *CI#+P
5"O.,H}
/** X_\otVh(D
* @return Returns the content. '16b2n+F@#
*/ V[Ui/M!9Z
publicList getContent(){ ,1o FPa{?
return content; j+
0I-p
} VS8Rx.?
^,T(mKS
/**
}?Ai87-{
* @return Returns the page. -C?ZB}`
*/ L0WN\|D
public Page getPage(){ b!5~7Ub.No
return page; UrEs4R1#
} :E )>\&
O[JL+g4
/** 6G""I]uT
* @param content o]I\6,T/|
* The content to set. %/ #NK1&M
*/ {[?(9u7R
public void setContent(List content){ 1NA.nw.
this.content = content; ^ sLdAC
} Cd}<a?m,
68WO~*
/** \n|EM@=eE
* @param page nk's_a*Z
* The page to set. sN01rtB(UT
*/ 6zuTQ^pz
publicvoid setPage(Page page){ ou{2@"
this.page = page; %^1V4
} V{3x!+q
} -fW*vE:
&(l9?EVq1
#fn)k1
=R$u[~Xl2X
:emiQ
2. 编写业务逻辑接口,并实现它(UserManager, Sw,+p
Ig0VW)@
UserManagerImpl) _H7x9
y=
java代码: #( 146
|~mOfuQb
ra
g Xn
/*Created on 2005-7-15*/ O`t&ldU
package com.adt.service; l L@XM2"
y(yHt=r
import net.sf.hibernate.HibernateException; `Cynj+PCe
$1L>)S
import org.flyware.util.page.Page; 9w"4K.
1JG'%8}#8
import com.adt.bo.Result; L2i_X@/
Pw`8Wj
/** nV/G8SeI
* @author Joa y'nK>)WG4
*/ E,x+JeKV
publicinterface UserManager { (m(JK^
u.m[u)HQ
public Result listUser(Page page)throws czgO ;3-C
V1`o%;j
HibernateException; K+K#+RBK
!6O(-S2A
}
goOCu
+`3)o PV)
Zbt.t]N
pG^
=M[bnq*\
java代码: SaAFz&WRl
}9# r0Vja
&P}_bx
/*Created on 2005-7-15*/ G+"t/?/
package com.adt.service.impl; L;NvcUFn
:tB1D@Cb6
import java.util.List; 6"5A%{J
{{D)YldtA
import net.sf.hibernate.HibernateException; H.|#c^I
gw3K+P
import org.flyware.util.page.Page; #64-~NVL_
import org.flyware.util.page.PageUtil; I7vz+>Jr
vzs)[AD
import com.adt.bo.Result; j<99FW"@e
import com.adt.dao.UserDAO; =_ ./~
import com.adt.exception.ObjectNotFoundException; 2Aazy'/
import com.adt.service.UserManager; c"n\cNP<
d *|Y
o
/** 2~1SQ.Q<RY
* @author Joa y^,1a[U.
*/ sV{,S>s
publicclass UserManagerImpl implements UserManager { ,c$_t+
V6&!9b
private UserDAO userDAO; 2G67NC?+
:uq\+(9
/** 9N%We|L,c
* @param userDAO The userDAO to set. 0d"[l@UU0
*/ qo90t{|c
publicvoid setUserDAO(UserDAO userDAO){ 1R{!]uh
this.userDAO = userDAO; *8yAG]z
} <EB+1GFuI
Qcq`libK
/* (non-Javadoc) |+FubYf?$
* @see com.adt.service.UserManager#listUser 'RQ+g}|Ba!
?cBwPetp
(org.flyware.util.page.Page) 3nIU1e
*/ SO|NaqWa
public Result listUser(Page page)throws !N\@'F!
c)TPM/>(p
HibernateException, ObjectNotFoundException { dUeN*Nq&(,
int totalRecords = userDAO.getUserCount(); N
,'GN[s
if(totalRecords == 0) axv>6k
throw new ObjectNotFoundException U3ADsdn
=r?hgGWe
("userNotExist"); $Uq|w[LA
page = PageUtil.createPage(page, totalRecords); {3>$[bT
List users = userDAO.getUserByPage(page); ~ drS} V
returnnew Result(page, users); u<7/0;D#+
} knu,"<
w=0(<s2
} iW]j9} t
nMq,F#`3N
!=*g@mgF
i^X]j
GfxZ'VIn
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 E<{R.r
<$A
询,接下来编写UserDAO的代码: aD<A.Lhy
3. UserDAO 和 UserDAOImpl: e8>})
java代码: y2Q&s9$Do
.KB^3pOpx
:;RMo2Tl
/*Created on 2005-7-15*/ SB;&GHq"n
package com.adt.dao; R$h<<v)%
j"t(0m
import java.util.List; 1*P~!2h
[SjqOTon{
import org.flyware.util.page.Page; 8l>?Pv
0JWDtmK=C
import net.sf.hibernate.HibernateException; =J]&c?I
P>y@kPi
/** t>L2
* @author Joa G*?8MTP8![
*/ bbDZ#DK"
publicinterface UserDAO extends BaseDAO { >2Y=*K,:
3H'sHuK"X
publicList getUserByName(String name)throws -mbt4w
f$o_e90mu
HibernateException; $f$SNx)),
z{%<<pZ
publicint getUserCount()throws HibernateException; J@/kIrx
pE3?"YO
publicList getUserByPage(Page page)throws \,'m</o~,
H9Gh>u]}
HibernateException; ,5P0S0*{
#z'
} ` _6C{<O
^7`BP%6
.y'>[
I:-Wy"i
CmWeY$Jb
java代码: 7RQR)DG
"6("9"
h!,v/7=
/*Created on 2005-7-15*/ (Nq=H)cm8
package com.adt.dao.impl; :ffY6L+
>^O7
import java.util.List; 8 %:Iv(UMk
^23~ZHu
import org.flyware.util.page.Page; m%0p\Y-/
I<DL=V
import net.sf.hibernate.HibernateException; 7:e{;iG
import net.sf.hibernate.Query; b8H{8{wi|
5G}?fSQ>
import com.adt.dao.UserDAO; Q1lyj7c#x
M+oHtX$
/** 05|=`eJ
* @author Joa
)| ccX
*/ MnmVl"(/
public class UserDAOImpl extends BaseDAOHibernateImpl hy9\57_#
1l9G[o
*
implements UserDAO { [=C6U_vU
v<k?Vu
/* (non-Javadoc) ; cNv\t
* @see com.adt.dao.UserDAO#getUserByName y-Fo=y
^ G]J ,+
(java.lang.String) -$\y_?}
*/ S*pGMuui
publicList getUserByName(String name)throws }ZYd4h|g\z
)',R[|<
HibernateException { />C^WQI^
String querySentence = "FROM user in class [\]50=&
"2!&5s,1p
com.adt.po.User WHERE user.name=:name"; WpDSg*fk=Y
Query query = getSession().createQuery b\f
O8{k
xl{=Y< ;
(querySentence); hy1oq7F(Q
query.setParameter("name", name); Fk7?xc
return query.list(); qyb?49I
} %64)(z
I]|Pq
/* (non-Javadoc) e
v}S+!|U
* @see com.adt.dao.UserDAO#getUserCount() t}a: p6D]
*/ ?9vuuIE
publicint getUserCount()throws HibernateException { ?JbilK}a
int count = 0; 4X/-4'
String querySentence = "SELECT count(*) FROM i%iL[id:w
VO5#Qg en
user in class com.adt.po.User"; s3N'02G
Query query = getSession().createQuery z9f-.72"X
]2A^1Del
(querySentence); XTs8s12
count = ((Integer)query.iterate().next
Q>qUk@
te`$%NRl
()).intValue(); E)&I@m
return count; 'ycJMYP8
} ^S<Y>Nm]
5&g@3j]
/* (non-Javadoc) \<h0Q,e
* @see com.adt.dao.UserDAO#getUserByPage 7O2/z:$f
>~rTqtKd
(org.flyware.util.page.Page) FgnTGY}
*/ k8yEdi`
publicList getUserByPage(Page page)throws 8$cLG*=h4
hF?1y `20
HibernateException { Y|m+dT6
String querySentence = "FROM user in class %Qgw7p4
P;y45b
com.adt.po.User"; yF:1( 4
Query query = getSession().createQuery X #dmo/L8
v~+(GqR=+
(querySentence); ~D+bh~
query.setFirstResult(page.getBeginIndex()) E =67e=h
.setMaxResults(page.getEveryPage()); 4KAZ ':
return query.list(); ;}WeTA_-[
} mUC)gA/
PQt")[
} w(Ovr`o?9t
)}R0Y=e
yN0Vr\r2
5pG}Yk_(x
tFn)aa~L
至此,一个完整的分页程序完成。前台的只需要调用 + 480 l}
, pfG
userManager.listUser(page)即可得到一个Page对象和结果集对象 %Xg4b6<9
R{4^t97wH{
的综合体,而传入的参数page对象则可以由前台传入,如果用 #Pau\|e_
uc{Ihw
webwork,甚至可以直接在配置文件中指定。 g/_5unI}u
!TH)
+zi
下面给出一个webwork调用示例: Kn{4;Xk\
java代码: 3NqB
<J
\\ij(>CI
:G=fl)!fE
/*Created on 2005-6-17*/ Ny7 S
package com.adt.action.user; 5I;&mW`1,`
"cGk)s
import java.util.List; N% B>M7-=
]m q|w
import org.apache.commons.logging.Log; M?49TOQA
import org.apache.commons.logging.LogFactory; .LZ?S"z$w
import org.flyware.util.page.Page; h*a(_11
",t?8465y
import com.adt.bo.Result; s^TZXCyF o
import com.adt.service.UserService; Wi<m{.%\E
import com.opensymphony.xwork.Action; =s{> Fsm1
*Q.>-J<S
/** =Bey gT^
* @author Joa Jr4Ky<G_i
*/ uZYF(Yu
publicclass ListUser implementsAction{ @bLy,Xr&
B@))8.h]
privatestaticfinal Log logger = LogFactory.getLog t+
TdLDJR
I{&[[7H
(ListUser.class); 59L\|OR
v~C
Czg
private UserService userService; FxY}m
Hio0HL-
private Page page; S+6.ZZ9c
,THw"bm
privateList users; {uFO/
Qljpx?E
/* V &T~zh1
* (non-Javadoc) MJ)RvNF
*
8W7J3{d
* @see com.opensymphony.xwork.Action#execute() I][*j
*/ 1.hyCTnI
publicString execute()throwsException{ Ee#q9Cx^J
Result result = userService.listUser(page); ?UR0:f:}oc
page = result.getPage(); }v{LRRi
users = result.getContent(); $wa{~'
return SUCCESS; Vp\,CuQ
} S13nL^=i
^DLfY-F+j
/** 6|=f$a
* @return Returns the page. 2[yd> (`
*/
/maJtX'
public Page getPage(){ 2tO,dx
return page; Rp7mh]kZ
} MN>b7O \.?
9=tIz
/** 1GRCV8"Z^
* @return Returns the users. 4J?0bZ
*/ G_JA-@i%
publicList getUsers(){ 372rbY
return users; TX/Xt7#R:
} ,p a {qne
'Is kWgc
/** y^*~B(T{
* @param page %;'s4ly
* The page to set. .{^5X)
*/ ^\% (,KNo
publicvoid setPage(Page page){ gJ{)-\
this.page = page; 6MW{,N
} !<";cw(q
[|L<_.8
/** B6 ;|f'e!
* @param users } OR+Io
* The users to set. j (d~aqW
*/ Ml5w01O
publicvoid setUsers(List users){ >=>2m2z=
this.users = users; v?$:@9pAk
} :cECRm*
o|:b;\)b
/** "sCRdx]_
* @param userService +\A,&;!SR
* The userService to set. 3hH<T.@)
*/ =nS3p6>rZ
publicvoid setUserService(UserService userService){ #!#
l45p6
this.userService = userService; gf@:R'$:+
} N+xP26D8
} WH} y"W
{P./==^0
aXYY:;
6gE7e|+
Vb_4f"
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ,4$>,@WW~
0OE:[pR
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 x9g#<2w8
X_h}J=33Q
么只需要: cT,sh~-x,
java代码: bE. .P&"
4$<JHo
@.
cq]6XK-W
<?xml version="1.0"?> ~
7s!VR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork q9_OGd|P
"8MF_Gu):
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7$=InK
0S~rgq|O
1.0.dtd"> ?`ZUR&
20
=,8]nwgo
<xwork> HV|,}Wks6s
r19
pZAc
<package name="user" extends="webwork-
Otuf]B^s
S\=Nn7"
interceptors"> )t#W{Gzfmh
TJRCH>E[a
<!-- The default interceptor stack name ^h6tr8yn
R 9\*#c
--> 3pKQ$\u
<default-interceptor-ref 6_Y,eL]"
~?BXti<!
name="myDefaultWebStack"/> ?tbrbkx
wHy!CP%
<action name="listUser" :I#V.
&QgR*,5eo
class="com.adt.action.user.ListUser"> SJ,v?=S!
<param } Kgy
/8S>;5hvK@
name="page.everyPage">10</param> T~e.PP
<result |{ip T SH
L8B!u9%
name="success">/user/user_list.jsp</result> 77Y/!~kd
</action> w?[u pn:K
Gc|idjW4
</package> K"MX!
y6a3tG
</xwork> 0 H:X3y+
WsB ?C&>x
U xGApK=X
>[#f\bG>
[(lW^-
M= (u]%\
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 !Uo4,g6r+
"y}5;9#,
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ]f_p8?j"
9.#<b|g
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 mfr|:i
z{QqY.Gu{G
W=?<<dVYD
2,b$7xaf
!nnC3y{G
我写的一个用于分页的类,用了泛型了,hoho >(<f 0
$&c*'3
java代码: _[BP0\dPW
hZb_P\1X
/n&&Um\
package com.intokr.util; :2`e(+Uz
,P0) 6>
import java.util.List; 8s@3hXD&
:ws<-Qy
/** f o3}W^0
* 用于分页的类<br> ;uGv:$([g
* 可以用于传递查询的结果也可以用于传送查询的参数<br> F+qm[Bc8
* flx(HJK
* @version 0.01 @6.vKCSE
* @author cheng ]SEZaT
*/ sI2^Qp@O1
public class Paginator<E> { $??I/6
privateint count = 0; // 总记录数 R=?[Nz
privateint p = 1; // 页编号 d'> x(Yi
privateint num = 20; // 每页的记录数 QJ;2ZN,
privateList<E> results = null; // 结果 tuX|\X
ueNS='+m
/** yHaGkm
* 结果总数 c71y'hnT
*/ dE3) |%
publicint getCount(){ |-H&o]
return count; Id9TG/H7
} er\|i. Y
L~3Pm%{@A
publicvoid setCount(int count){ lB4WKn=?Kl
this.count = count; 6S#Cl>v
} 7yQ4*UB
Lw,h+@0
/** M6TD"-
* 本结果所在的页码,从1开始 /-s6<e!
* |s_GlJV.
* @return Returns the pageNo. DmcZta8n]
*/ 1Y,Z
%d
publicint getP(){ kx^/*~ex
return p; K=&>t6s<
} *qq+jsA6wH
XWw804ir
/** {;oPLr+Z
* if(p<=0) p=1 J}t%p(mb
* :(%5:1W
* @param p lTsjxw
o
*/ "@ n%Z
publicvoid setP(int p){ dh\P4
if(p <= 0) =(^3}x
p = 1; mE[y SrV
this.p = p; V]^$S"Tv
} X8\GzNE~R
An@t?#4gxi
/** ssL\g`xe
* 每页记录数量 xSu >
*/ F0#
'WfM#
publicint getNum(){ *zLMpL_
return num; AQ Ojit6p
} qQa}wcU'9p
:6dxtl/{b:
/** Y);=TM6s
* if(num<1) num=1 I1J-)R+
*/ *1"+%Z^
publicvoid setNum(int num){ =~gvZV-<
if(num < 1) 9YGY,sx
num = 1; JXxwr)i
this.num = num; Xa&kIq}(g
} /wv0i3_e
<3
uNl
/** '%;m?t%q
* 获得总页数 nt<]d\o0
*/ d-%hjy3N
publicint getPageNum(){ Sjj6q`
return(count - 1) / num + 1; @)}L~lb[)
} Y-9I3?ar
&5;"#:ORcK
/** (k P9hcV
* 获得本页的开始编号,为 (p-1)*num+1 (m$Y<{)2
*/ +`15le`R
publicint getStart(){ *WZA9G#V5
return(p - 1) * num + 1; 4ppz,L,4
} JGZBL{8
n"8Yv~v*2j
/** EX"yxZ~
* @return Returns the results. K NOIZj
*/ n{jGOfc
publicList<E> getResults(){ "
1tH
return results; >mkFV@`
} jWgX_//!
s#MPX3itK
public void setResults(List<E> results){ }0 ?3:A
this.results = results; 4e
} ig"L\ C"T
,)io5nZF
public String toString(){ 5twhm
StringBuilder buff = new StringBuilder F[MFx^sT{
MfkZ
(); {)Xy%QV
buff.append("{"); &j6erwaT
buff.append("count:").append(count); 4z)]@:`}z
buff.append(",p:").append(p); {[F A#
buff.append(",nump:").append(num); a.Vuu)+Quw
buff.append(",results:").append h`KU\X )A
<naz+QK'
(results); [B3RfCV{
buff.append("}"); 0"#HJA44
return buff.toString(); .]Z"C&"N]
} |?9HU~B
L.IlBjD
} ! P4*+')M
2zpr~cB=
DwF hK*