Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 U voX\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "8&pT^
7!#x-KR~5
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 0_}OKn)J
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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 ?5Wj y
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。 4v33{sp
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分页支持类:
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java代码: e Pq(:ih
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package com.javaeye.common.util; A)kx,,[
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import java.util.List; f'0n^mSP
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publicclass PaginationSupport { sHyhR:
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publicfinalstaticint PAGESIZE = 30; w>p0ldi
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privateint pageSize = PAGESIZE; \6-x~%xK
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privateList items; Ds9pXgU(Z
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privateint totalCount; L)a8W
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privateint[] indexes = newint[0]; h=.|!u
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privateint startIndex = 0; pzbR.L}'D
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public PaginationSupport(List items, int 01g=Cg
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totalCount){ K}tl,MMU
setPageSize(PAGESIZE); /1F%w8Iqh
setTotalCount(totalCount); i6?,2\K
setItems(items); %%`Nq&'
setStartIndex(0); #:s*)(Qn
} P,k~! F^L
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public PaginationSupport(List items, int 8*!<,k="9
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totalCount, int startIndex){ 0;2i"mzS\
setPageSize(PAGESIZE); :'91qA%Wr
setTotalCount(totalCount); uz-,)
setItems(items); +D[|L1{xb
setStartIndex(startIndex); R
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} <k<K"{
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public PaginationSupport(List items, int Ve*NM|jg
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totalCount, int pageSize, int startIndex){ I 8vv
setPageSize(pageSize); MP(R2y
setTotalCount(totalCount); btHN
setItems(items); j5,1`7\7B
setStartIndex(startIndex); Umjt~K^Z
} veAg?N<c
p
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publicList getItems(){ I|9(*tq)
return items; G#gUd'=M
} lYmqFd~p
-$**/~0zU
publicvoid setItems(List items){ @X4Ur+d
this.items = items; a
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} V>ML-s9
L^bt-QbhO
publicint getPageSize(){ 7K,Quq.%+
return pageSize; 4z#{nZG
} 3sIW4Cs7)U
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IrV
publicvoid setPageSize(int pageSize){ ZQXv-"
this.pageSize = pageSize; u?5d%]*
} _8P"/(
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) DXN|<A
publicint getTotalCount(){ 0]4kR8R3[
return totalCount; gD10C,{
} {a^A-Xh[u
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publicvoid setTotalCount(int totalCount){ Zu`;
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if(totalCount > 0){ h6<abT@I
this.totalCount = totalCount; ~T@t7Cg
int count = totalCount / BZejqDr*
x|U~?
pageSize; F-[zuYGp
if(totalCount % pageSize > 0) SF$7WG3Q
count++; >$SP2(Y~
indexes = newint[count]; &[:MTK?x!
for(int i = 0; i < count; i++){ ma9q?H#X
indexes = pageSize * [ -"o5!0<
gNF8&T
i; F1) B-wW
} vQ/}E@?u
}else{ PLU8:H@X
this.totalCount = 0; nlmc/1C
}
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} A'r 3%mC
E9z^# @s
publicint[] getIndexes(){ =y-L'z&r
return indexes; M4
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} rCfr&>nn
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publicvoid setIndexes(int[] indexes){ uMVM- (g%
this.indexes = indexes; %|E'cdvkX
} nfpkWyI u{
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publicint getStartIndex(){ mAMi-9
return startIndex; VeiJ1=hc
} JLUG=x(dA
#[0:5$-[
publicvoid setStartIndex(int startIndex){ ?3X!
if(totalCount <= 0) ddvSi6
this.startIndex = 0; ie|I*;#
elseif(startIndex >= totalCount) fHhm)T8KB
this.startIndex = indexes Atl`J.;G
F}3<q
[indexes.length - 1]; !`=ms1%U
elseif(startIndex < 0) e9e%8hL
this.startIndex = 0; n@n608
else{ jy@vz,/:%5
this.startIndex = indexes F x,08
~f=~tN)hZ
[startIndex / pageSize]; jJFWPD]u
} }/~%Ysl
} 9ZvBsG)
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publicint getNextIndex(){ ?xEQ'(UBQ
int nextIndex = getStartIndex() + /~3~Xc~=p
(Mi]vK.4
pageSize; Y.`
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if(nextIndex >= totalCount) Y<|!)JLB2
return getStartIndex(); S\fEV"
else Gr9/@U+
return nextIndex;
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} Fe
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}L
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publicint getPreviousIndex(){ /2}o:vLj
int previousIndex = getStartIndex() - Q#C;4)e
MuNM)pyxp
pageSize; 5`qt82Qm
if(previousIndex < 0) ,XT#V\qne
return0; nk.Y#+1)
else [Du@go1C
return previousIndex; GT\,
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} n\d`Fk
i`[5%6\"&
} [MSLVTR
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抽象业务类 dWHl<BUm
java代码: v|5:;,I
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/** /H#- \r&r
* Created on 2005-7-12 2|'v[
*/ a*LT <N
package com.javaeye.common.business; YnnpgR.
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import java.io.Serializable; csn/h$`-@
import java.util.List; D'V0b"
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import org.hibernate.Criteria; TU ]Ed*'&
import org.hibernate.HibernateException; 6#~"~WfPQ
import org.hibernate.Session; ~wnTl[:
import org.hibernate.criterion.DetachedCriteria; &gJKJ=7
import org.hibernate.criterion.Projections; }~P%S(zB
import fDc>E+,
36>pa
org.springframework.orm.hibernate3.HibernateCallback; z0J$9hEg89
import ^NJ]~h{n$
Zgp]s+%E
org.springframework.orm.hibernate3.support.HibernateDaoS [6x-c;H_4
0_yE74i
upport; F#=XJYG1
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import com.javaeye.common.util.PaginationSupport; {MmHR
`@GqD
public abstract class AbstractManager extends >cwyb9;!kK
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HibernateDaoSupport { K/RQ-xd4
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privateboolean cacheQueries = false; (H *-b4]/
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privateString queryCacheRegion; [c4.E"
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publicvoid setCacheQueries(boolean HZMs],GX
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cacheQueries){
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this.cacheQueries = cacheQueries; :T~Aa(%(
} /UeLf$%ZW
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publicvoid setQueryCacheRegion(String Oq"(oNG@
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queryCacheRegion){ ~82[pY
this.queryCacheRegion = o?\)!_Z|
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queryCacheRegion; UnNvlkjq9
} )#-27Y
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publicvoid save(finalObject entity){ gA
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getHibernateTemplate().save(entity); mhTpR0
} ZK5(_qW&i
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publicvoid persist(finalObject entity){ 4X7y}F.J
getHibernateTemplate().save(entity); Wz$%o'OnC
} @k~?h=o\b
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publicvoid update(finalObject entity){ E/cA6*E[.<
getHibernateTemplate().update(entity); }GvoQ#N
} U
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publicvoid delete(finalObject entity){ 8xhXS1
getHibernateTemplate().delete(entity); GZT}aMMSJ
} }C>Q
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publicObject load(finalClass entity, dJ\6m!Mp
/^96|
finalSerializable id){ !8&,GT
return getHibernateTemplate().load a?' 3
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(entity, id); xVoWGz7
} 1wUZ0r1'
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publicObject get(finalClass entity, xrx{8pf
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finalSerializable id){ KsYT3
return getHibernateTemplate().get A/N*Nc
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(entity, id); hTI8hh
} .;WJ(kB\U
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publicList findAll(finalClass entity){ THHrGvb
return getHibernateTemplate().find("from tW5\Ktjno
a:@9GmtV&
" + entity.getName()); vy/U""w`
} &QE^i%6>\
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publicList findByNamedQuery(finalString I^Ichn
*lv)9L+0
namedQuery){ Y~1}B_
return getHibernateTemplate etf ft8
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().findByNamedQuery(namedQuery); 7UHqiA`L
} ?97MW a
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publicList findByNamedQuery(finalString query, q?z6|]M|u
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finalObject parameter){ Qpd-uC_Ni
return getHibernateTemplate YN] w_=
}7hpx!s,
().findByNamedQuery(query, parameter); j5z, l
} *F:]mgg
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0
publicList findByNamedQuery(finalString query, !boKrSw
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finalObject[] parameters){ $o\p["DP
return getHibernateTemplate 3iYz<M
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().findByNamedQuery(query, parameters); GG"0n{>0
} Js+d4``W
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publicList find(finalString query){ !~UI~-i'
return getHibernateTemplate().find y:4Sw#M%(
;0E"4(S.q1
(query); j-gLX
} ;TSnIC)c
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publicList find(finalString query, finalObject a2/r$Tgm
9?D7"P+
parameter){ w:FH2*
return getHibernateTemplate().find &_4A6
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(query, parameter); +lJuF/sS8m
} ?3SlvKI}H`
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public PaginationSupport findPageByCriteria B0p>' O2
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(final DetachedCriteria detachedCriteria){ =)M 8>>l
return findPageByCriteria };9dd3X
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); PkDL\Nqe
} gZM{]GQ
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public PaginationSupport findPageByCriteria ! qrF=a
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(final DetachedCriteria detachedCriteria, finalint dMGu9k~u
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startIndex){ HKOJkbVZ2^
return findPageByCriteria -Qnnzp$]
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(detachedCriteria, PaginationSupport.PAGESIZE, mMN oR]
:^%soEi
startIndex); I-/PzL<W P
} y=h2_jt
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public PaginationSupport findPageByCriteria q,nj|9z V
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(final DetachedCriteria detachedCriteria, finalint
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)2S0OY.
pageSize, /oiAAB27
finalint startIndex){ JS(KCY 9
return(PaginationSupport) YD@V2gK
&tMvs<q,
getHibernateTemplate().execute(new HibernateCallback(){ @1n0<V/
publicObject doInHibernate VPN@q<BV
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(Session session)throws HibernateException { czMLvPXRx
Criteria criteria = bSz6O/A/
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detachedCriteria.getExecutableCriteria(session); AX'(xb,
int totalCount = }i[i{lKj
t ?bq~!X
((Integer) criteria.setProjection(Projections.rowCount 0?p_|X'_
Y2<#%@%4
()).uniqueResult()).intValue(); ULU
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criteria.setProjection d0-}Xl
pbqa
(null); =1yUH9\,b
List items = &}T`[ d_Z
)>\Ne~%
criteria.setFirstResult(startIndex).setMaxResults ,?&hqM\
E}NX+ vYF
(pageSize).list(); CKh-+8j
PaginationSupport ps = 7%7_i%6wP
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new PaginationSupport(items, totalCount, pageSize, G Q8I |E
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startIndex); EXJ>Z
return ps; B/5C jHz
} ev8E.ehD
}, true); @.0jC=!l
} W!tP sPM
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public List findAllByCriteria(final g"T~)SQP
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DetachedCriteria detachedCriteria){ f[|xp?ef
return(List) getHibernateTemplate TqQ>\h"&_
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().execute(new HibernateCallback(){ $ ~D`-+J
publicObject doInHibernate :~T:&;q0
uL-i>!"L!}
(Session session)throws HibernateException { Hlz4f+#I
Criteria criteria = + !_^MB kk
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detachedCriteria.getExecutableCriteria(session); Q 5@~0
return criteria.list(); W{-N,?z
} f2{4Y)
}, true); }WCz*v1Wq
} 2o\\qEYg
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public int getCountByCriteria(final V7lDuiAI
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DetachedCriteria detachedCriteria){ 0A1l"$_|
Integer count = (Integer) kN}.[enI~
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getHibernateTemplate().execute(new HibernateCallback(){ R8],}6,;E}
publicObject doInHibernate zb;'}l;+
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(Session session)throws HibernateException { x7NxHTL
Criteria criteria = RIJBHOa
q!AS}rV
detachedCriteria.getExecutableCriteria(session); |xf%1(Rl@
return t S!~>X
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criteria.setProjection(Projections.rowCount Z&.FJZUP
*E$D,
()).uniqueResult(); zZf#E@=$|
} }(hE{((o
}, true); MnX2sX|
return count.intValue(); z4f5@
} Y^6=_^
} t: [[5];E
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用户在web层构造查询条件detachedCriteria,和可选的 x%(!+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 hG
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PaginationSupport的实例ps。 \DQ; v
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ps.getItems()得到已分页好的结果集 X,OxvmDm
ps.getIndexes()得到分页索引的数组 %
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ps.getTotalCount()得到总结果数 +pFz&)?
ps.getStartIndex()当前分页索引 R/b=!<
ps.getNextIndex()下一页索引 D:F!;n9
ps.getPreviousIndex()上一页索引 AVcZ.+?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 &c\8`# 6
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 qkBnEPWZy
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一下代码重构了。 WYh7Y
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我把原本我的做法也提供出来供大家讨论吧: zh4o<f:-
snK9']WXo
首先,为了实现分页查询,我封装了一个Page类: H~$|y9>qI
java代码: #`W8-w
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/*Created on 2005-4-14*/ 3{_+dE"9
package org.flyware.util.page; G6J3F
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/** X:e'@]Z)?
* @author Joa J`V6zGgW
* 3{c&%F~!
*/ UG!&n@R
publicclass Page { ;{ezK8FJ}@
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/** imply if the page has previous page */ jxoEOEA
privateboolean hasPrePage; 9z-"JnM
pTN_6=Y"
/** imply if the page has next page */ zCQv:.0L
privateboolean hasNextPage; TxiJ?sDh*
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/** the number of every page */ Th8Q~*v
privateint everyPage; L*l( ~t)vF
\UC4ai2MK
/** the total page number */ 1rKR=To
privateint totalPage; .DX#:?@4@Y
[Dt\E4
/** the number of current page */ D H.ljGb
privateint currentPage; bHMlh^{`%
fSP~~YSeU
/** the begin index of the records by the current ~q4y'dBy*
_<~05Eh
query */ '0=U+Egp
privateint beginIndex; 4 '+)9&g
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/** The default constructor */ !kIw835U
public Page(){ 4v!@9.!vQ
6JL
7ut
} |-R::gm
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/** construct the page by everyPage DTJ
* @param everyPage Ky'^AN]
* */ u)V*o
public Page(int everyPage){ PQ[TTLG\&
this.everyPage = everyPage; X-duG*~
} H{V-C_
e,x@?L*
/** The whole constructor */ oO|^ [b#
public Page(boolean hasPrePage, boolean hasNextPage, _+. t7q^
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int everyPage, int totalPage, y,
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int currentPage, int beginIndex){ =#u2Rx%V
this.hasPrePage = hasPrePage; h1Lp:@:|
this.hasNextPage = hasNextPage; (r|T&'yK
this.everyPage = everyPage; 7q?YdAUz
this.totalPage = totalPage; <
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this.currentPage = currentPage; +-Dd*yD6<
this.beginIndex = beginIndex; c`>\R<Z ]
} 3xe8DD
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/** UtutdkaS
* @return dnx}c4P
* Returns the beginIndex. GGBe/X
*/ a~%ej.)l
publicint getBeginIndex(){ %,^7J;
return beginIndex; U%4g:s
} 70NHU;&N
j\vK`.z
/** i`Yf|^;@2>
* @param beginIndex q5A+%#
* The beginIndex to set. `~RV
*/ ?
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publicvoid setBeginIndex(int beginIndex){ K c<z;
this.beginIndex = beginIndex; fH.W
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} WY,t> 1c
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/** "tark'
* @return =oTYwU
* Returns the currentPage. v Y\O=TZT
*/ A)#sh)
}Q
publicint getCurrentPage(){ >R:+ml
return currentPage; %8tN$8P
} =4D_-Q
KCu6:)6'
/** q+z\Y?
* @param currentPage ""+*Gn7^8
* The currentPage to set. Fs|;>Up0
*/ ob7_dWAG
publicvoid setCurrentPage(int currentPage){ .g#=~{A
this.currentPage = currentPage; V[M#qZS
} vw]nqS~N
OgS8.wX
/** J9FNjM[qe
* @return kn"x[{d
* Returns the everyPage. O}-7 V5
*/ nnNg^<[k3
publicint getEveryPage(){ 0%F.]+6[O4
return everyPage; (3h*sd5ly
} }Yl=lcvw
E?mp6R]}%
/** Q75^7Ga_
* @param everyPage ?<?C*W_
* The everyPage to set. KUut C
:
*/ +I n"OR%
publicvoid setEveryPage(int everyPage){ g)A0PvEu
this.everyPage = everyPage; fB96Q
} mv.I.EL
RG3G},Q
/** Q$0%~`t
* @return %m) h1/l
* Returns the hasNextPage. )JQQ4D
*/ {Yk20Zn
publicboolean getHasNextPage(){ mv?H]i`N
return hasNextPage; y7-:l u$9
} J\ +gd%
0|!<|N<
/** 8VmN?"5v
* @param hasNextPage }.cmiC
* The hasNextPage to set. +fQL~0tA
*/ 25n(&NV
publicvoid setHasNextPage(boolean hasNextPage){ rOHW
this.hasNextPage = hasNextPage; (I
ds<n"
} &jZ|@K?
J<#`IaV
/** ENWB|@B
* @return $A@3ogoS&
* Returns the hasPrePage. Pd "mb~
*/ yLO
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publicboolean getHasPrePage(){ ^s~n[
return hasPrePage; `ab\i`g9
} 5%+bWI{w
O;e8ft
'|
/** 0 ;_wAk
* @param hasPrePage ObyuhAR
* The hasPrePage to set. N3yB1_
*/ RvS q KW8
publicvoid setHasPrePage(boolean hasPrePage){ iQzX-a|4]
this.hasPrePage = hasPrePage; EPe]-C`
} -)OkG#J@
]6BmCh
/** 8yWu{'G
* @return Returns the totalPage. 8f,'p}@!d
* ,B~lwF9
*/ 45)ogg2
publicint getTotalPage(){ qbU1qF/
return totalPage; ~njbLUB
} l!;_lH8W$
ZcTL#OTP
/** U +*oI *
* @param totalPage &V#z kW
* The totalPage to set. {yHB2=nI
*/ 0^&(u:~
publicvoid setTotalPage(int totalPage){ uRm _
this.totalPage = totalPage; >' ksXA4b
} Wj4^W<IO
! 2Xr~u7a
} rv,NQZ
!u53 3
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0)~
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K$<`4#i
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 5%QC
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4+5OR&kxZ
个PageUtil,负责对Page对象进行构造: [ZKtbPHb
java代码: GX7 eRqz >
2q-:p8
bB;~,W&E1
/*Created on 2005-4-14*/ Q 7uAf3
package org.flyware.util.page; *>aZc::
U0h)pdo
import org.apache.commons.logging.Log; T2:oWjC3$
import org.apache.commons.logging.LogFactory; 8tLT'2+H#
{=bg5I0|a
/** ]&C:>
* @author Joa FDF3zzP0
* <.r ]dCf
*/ qe5tcv}u
publicclass PageUtil { stg30><
?qg^WDs$
privatestaticfinal Log logger = LogFactory.getLog bkr~13S{+
q GpP,
(PageUtil.class); I|g@W_
lh,ylh
/** ?iPZsV
* Use the origin page to create a new page E!zd(
* @param page ( zn_8s
* @param totalRecords n|70x5Z?}J
* @return $` Z>Lm*
*/ @<D'-mMt
publicstatic Page createPage(Page page, int tt6.
jo
yhcNE8mkQ/
totalRecords){ =vqsd4
return createPage(page.getEveryPage(), KInUe(g<9M
ku/\16E/k
page.getCurrentPage(), totalRecords); Sf
024
} J3/\<=Qh
[x;(cISK1
/** Ku<b0<`
* the basic page utils not including exception gYTyH.
2{A;du%&
handler ,|T*|2Gm
* @param everyPage M82.khm~jM
* @param currentPage 8hTR*e!+
* @param totalRecords <|{L[
* @return page pN\)(:"8v
*/ 9W{,=.%MX$
publicstatic Page createPage(int everyPage, int CfPXn0I
RLdlz
currentPage, int totalRecords){ )KSisEL
everyPage = getEveryPage(everyPage); :/o C:z\h
currentPage = getCurrentPage(currentPage); { 1+Cw?1d
int beginIndex = getBeginIndex(everyPage, A",eS6
i\t753<Ys
currentPage);
xS=_yO9-
int totalPage = getTotalPage(everyPage, <8u>_o6
o3Mf:;2c C
totalRecords); BZovtm3E
boolean hasNextPage = hasNextPage(currentPage, k$ZRZ{
E+
)R jb/3*!
totalPage); 99 <4t$KH
boolean hasPrePage = hasPrePage(currentPage); E%<w5d.lq
v<L=!-b^
returnnew Page(hasPrePage, hasNextPage, nd.57@*M
everyPage, totalPage, J.1O/Pw!.a
currentPage, P@qMJ}<j
7~_{.f
beginIndex); Yo >`h2C4
} x&at^Fp
CQ@LmTW[
privatestaticint getEveryPage(int everyPage){ $Mdbto~ <
return everyPage == 0 ? 10 : everyPage; LtC~)R
} AXz-4,=xX
:lUX5j3
privatestaticint getCurrentPage(int currentPage){ "yg.hK`
return currentPage == 0 ? 1 : currentPage; :W~6F*A
} o^HNF+sm
Z}|TW~J=
privatestaticint getBeginIndex(int everyPage, int b<[jaI0
xC<=~(
currentPage){ qs=Gj?GwGQ
return(currentPage - 1) * everyPage; ):e+dt
} J!rY
6[t
j7K5SS_]
privatestaticint getTotalPage(int everyPage, int k/% #>
ZAMeqPt
totalRecords){ Hal7
MP
int totalPage = 0; }K2
/&kZ
!_qskDc-
if(totalRecords % everyPage == 0) w#oGX
totalPage = totalRecords / everyPage; :*^:T_U
else Vzpt(_><
totalPage = totalRecords / everyPage + 1 ; 59.$ULQVMY
k!T|)\nc+
return totalPage; q(,cYu
} !{;[xXK4M
! 0^;;'
privatestaticboolean hasPrePage(int currentPage){ fV 3r|Bp
return currentPage == 1 ? false : true; 3filAGR?
} z<hFK+j,'^
Re>AsnA[
privatestaticboolean hasNextPage(int currentPage, l09Fn>wa
u^Vh.g]
int totalPage){ jAXR`D
return currentPage == totalPage || totalPage == cv2]*
2gt+l?O<PS
0 ? false : true; ^EF'TO$
} yf!,4SUkU
:Zza)>l
UVrQV$g!
} k}GjD2m
Q
$]YD
pCM
y,Jh@n';|
{3LA%xO
_pW_G1U
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。 Av o|v>
Mi]I:ka
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 (?vK_{
8!&nKy<Y
做法如下: $xT1 1 ^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D|l,08n"?
r4u z} jl{
的信息,和一个结果集List: X1oGp+&
java代码: n#4Gv|{XMD
I.1D*!tz
Y6A;AmM8
/*Created on 2005-6-13*/ t0q_>T-kt
package com.adt.bo; e'34Pw!m
Pe}PH
I
import java.util.List; u^=`%)
T?n-x?e
import org.flyware.util.page.Page; %t*[T
~h!
13!
/** GX
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* @author Joa /4*W DiH
*/ vg)Z]F=t(
publicclass Result { :=*}htP4C
KVN"XqE4
private Page page; [[WF0q
!;v.>.lw
private List content; Mu{BUtkzG
~EEs}i
/** 9#qeFBI
* The default constructor pISp*&
*/ dFW.}"^c
public Result(){ CQgcC-)ns]
super(); *nRNg.i3D
} s5&=Bsv
m2xBS!fm
/** io.]'">
* The constructor using fields .IgRY\?Q
* K*Ks"Vx
* @param page 'H|~u&?
* @param content qM",( Bh
*/ ]]2k}A[-I
public Result(Page page, List content){ 5dl,co{q
this.page = page; QB&BTT=!
this.content = content; T_LLJ}6M
} $'{=R 45Z
71"+<C .
/** ]a?bzOr,
* @return Returns the content. $shp(T,q
*/ X:EEPGE
publicList getContent(){ 7C7>y/uS
return content; 7O)" `
} #H~_K}Ks
\S ."?!U
/** booRrTS
* @return Returns the page. .TpsJXF
*/ /[=E0_t+
public Page getPage(){ I[d]!YI}F
return page; <41ZZ0<EwY
} QA?oJ_}y
fDh]tua
/** .tnkT;T
* @param content =:=/Gz1
* The content to set. `s"d]/85VW
*/ d
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public void setContent(List content){ g`0moXz
this.content = content; n lGHT
} ^U@~+dw
iPj~I
/** H'DVwnn>ik
* @param page !L$x:/R9M
* The page to set. ?X9UTOx
*/ 4w93}t.z
publicvoid setPage(Page page){ Z[?mc|*x
this.page = page; e,0-)?5R
} O
)d[8jw"
} F #`=oM$5
fjG&`m#"
wTc)S6%7
j:,9%tg
91Z'
2. 编写业务逻辑接口,并实现它(UserManager, Vzg=@A#
}m-"8\_D
UserManagerImpl) IG ~`i I
java代码: C! 9}
)[Z!*a m
iE].&>w
/*Created on 2005-7-15*/ w@-M{?R
package com.adt.service; 6.WceWBR
eWs&J24
import net.sf.hibernate.HibernateException; H t(n%;<
}G
VX>p
import org.flyware.util.page.Page; 3gEMRy*+
i^msjA
import com.adt.bo.Result; <0P5 o|
YJV% a
/** TrS8h^C
* @author Joa 3uWkc3
*/ 8'
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publicinterface UserManager { p4!:]0c
Q\ppfc{,
public Result listUser(Page page)throws Yf@e=:
X{xBYZv4
HibernateException; W~1~k{A
zAzP,1$?
} co8"sz0(U
Yr.sm!xA
Qn@Pd* DR
H,unpZ(
I#F!N6;
java代码: D\dWt1n
l7H
qo)
YyAJ m^o
/*Created on 2005-7-15*/ "TyJP[/
package com.adt.service.impl; u$#Wv2| mk
q[q?hQ/b
import java.util.List; RD7^&
sUJ%x#u}Fk
import net.sf.hibernate.HibernateException; |1b_*G4|
>{gPN"S"a
import org.flyware.util.page.Page; D"(L5jR8m@
import org.flyware.util.page.PageUtil; @hQlrq5c
fWfk[(M'9
import com.adt.bo.Result; &s Pq<l o
import com.adt.dao.UserDAO; '. Ed`?<p
import com.adt.exception.ObjectNotFoundException; `nM/l@
import com.adt.service.UserManager; BS Iy+
DI+]D~N
/** 00v&lQBW
* @author Joa u0aJu
*/ N{
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publicclass UserManagerImpl implements UserManager { Nkxmm/Z
|(5W86C,ju
private UserDAO userDAO; ];'v8)Y
wW>zgTG
/** 5;0g!&-t#
* @param userDAO The userDAO to set. Dd;Nz
*/ N\:.
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publicvoid setUserDAO(UserDAO userDAO){ p' M%XBu
this.userDAO = userDAO; W;bu2ym&Q
} yFDv6yJ.
;};wq&b#
/* (non-Javadoc) 3 "o"fl
* @see com.adt.service.UserManager#listUser /}Jj
a=M\MZK>
(org.flyware.util.page.Page) GpZc5c
*/ ?5_7;Ha
public Result listUser(Page page)throws kOIt(e
_g1b{$
HibernateException, ObjectNotFoundException { r.4LU
int totalRecords = userDAO.getUserCount(); !r#?C9Sq
if(totalRecords == 0) -S3MH1TZ
throw new ObjectNotFoundException $O9^SB
Fx-8M!
("userNotExist"); 9U$EJN_G
page = PageUtil.createPage(page, totalRecords); ^G6RjJxqp8
List users = userDAO.getUserByPage(page); vAyFm dJ^
returnnew Result(page, users); CPNL
94x
} >3z5ww
&u#&@J
} pdE3r$C
?LvCR_D:
zZVfj:i8
z dO#0tN
PRz/inru-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _YcA+3ZL
f=)2f=
询,接下来编写UserDAO的代码: (SKVuR%Jj
3. UserDAO 和 UserDAOImpl: aN"DkUYZM
java代码: /yM:|`tT
m1Y>Nj[f
a4irokJv#
/*Created on 2005-7-15*/ R
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package com.adt.dao; {&"N%;`Q
kF/9-[]$g,
import java.util.List; rETRTp0HT
cJ54s}
import org.flyware.util.page.Page; )/z@vY
Mn)@{^
import net.sf.hibernate.HibernateException; mdRU^n
aH^RoG}
/** &^W|iXi#
* @author Joa I1PuHf Qs
*/ =}.EY iD
publicinterface UserDAO extends BaseDAO { Dk?\)lD`
4'0Dr++
publicList getUserByName(String name)throws qK)73eNSR
DZi!aJ
HibernateException; ~8lwe*lNV
r/SG 4
publicint getUserCount()throws HibernateException; _-EyT
3YVi"
k?2
publicList getUserByPage(Page page)throws ?M[ A7?
;VWAf;U;B
HibernateException; $sEy%-
'Fmvu
} St e=&^
Y.*y9)#S6
/iX+ R@
tg{H9tU;
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java代码: *8LMn
7}X[
4("bB
9=UkV\m)
/*Created on 2005-7-15*/ '_V2!?+RU+
package com.adt.dao.impl; t^w"w`v\u
p\bDY
import java.util.List; ~$~5qwl
p\<u6v ~J
import org.flyware.util.page.Page; SLh(9%S;
/kfgx{jZ
import net.sf.hibernate.HibernateException; ['T:ea6B
import net.sf.hibernate.Query; ;aw=MV
_'(,
import com.adt.dao.UserDAO; uuQ(&
o93`|yWl
/** 0zi~p>*nJC
* @author Joa $C `;fA
*/ /oriW;OF
public class UserDAOImpl extends BaseDAOHibernateImpl zRyuq1Zyc,
vMS
|$L
implements UserDAO { 0PWg;>^'
^Y'HaneoM
/* (non-Javadoc) >"C,@cN}B
* @see com.adt.dao.UserDAO#getUserByName UXh9:T'%
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(java.lang.String) l g-X:Z.
*/ {DR`;ea])1
publicList getUserByName(String name)throws [<6S%s
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HibernateException { {HCzp,Y
String querySentence = "FROM user in class a]MX)?
% ClHCoyA
com.adt.po.User WHERE user.name=:name"; ;dJ1
Query query = getSession().createQuery -q*i_r:,
@~%r5pz6
(querySentence); kOed ]>H
query.setParameter("name", name); "T|PS6R~
return query.list(); A -b
[>}_
} *m#Za<_Gv
yrlf+tl
/* (non-Javadoc) Y 1t\iU
* @see com.adt.dao.UserDAO#getUserCount() Wr( y)D<y}
*/ =17t-
[
publicint getUserCount()throws HibernateException { H XmS|PX
int count = 0; FAj)OTI2S
String querySentence = "SELECT count(*) FROM +1D+]*t_?[
3nhXZOO1
user in class com.adt.po.User"; HBMhtfWW
Query query = getSession().createQuery \Rp-;.I@6
* cgI.+
(querySentence); 9_
dpR.
count = ((Integer)query.iterate().next [xGf,;Z
7eiV{ tYF
()).intValue(); %;rHrDP(>
return count; *#C+iAF|)'
} lk( }-
v~^{{O
/* (non-Javadoc) $GTU$4u
* @see com.adt.dao.UserDAO#getUserByPage fe9LEM8j
[Ki0b^
(org.flyware.util.page.Page) -&-Ma,M?
*/ +>r/ 0b
publicList getUserByPage(Page page)throws c\Q7"!e
nuw70*ell
HibernateException { W#hj 1
String querySentence = "FROM user in class =,UWX3`f
Y$?9Zkp>
com.adt.po.User"; Ym =FgM\
Query query = getSession().createQuery 3 yB!M
6e[VgN-s
(querySentence); lw<c2C
query.setFirstResult(page.getBeginIndex()) o*o/q],C9-
.setMaxResults(page.getEveryPage()); GhIKvX_N
return query.list(); SgS~ {4Zx*
} Mw;sLsu
2u5|8
} i*@<y/&'
(w}H]LQ
yc?a=6q'm
Uk6HQQ
x;8A!8w
至此,一个完整的分页程序完成。前台的只需要调用 AD|2qM))
~x]jB
userManager.listUser(page)即可得到一个Page对象和结果集对象 L2[f]J%
%@6}GmK^
的综合体,而传入的参数page对象则可以由前台传入,如果用 jW
3c"
LILQ\I<<'
webwork,甚至可以直接在配置文件中指定。 #g]vc_V
`0Oh_8"
下面给出一个webwork调用示例: "$2y-|
java代码: n:{qC{D-qS
'coV^~qy
pLLGus+W
/*Created on 2005-6-17*/ Bi
@2
package com.adt.action.user; O4og?h>
y9>ZwYN
import java.util.List; ~2gG(1%At9
%3ICI
import org.apache.commons.logging.Log; 1f":HnLRM
import org.apache.commons.logging.LogFactory; 3ZXQoC '
import org.flyware.util.page.Page; hMykf4
v#U"pn|M
import com.adt.bo.Result; 7G/1VeVjB
import com.adt.service.UserService; u[DfzH
import com.opensymphony.xwork.Action; N-e @j4WU
[<
&oF
/** osX8eX]\
* @author Joa gk0( ANx
*/ fmb} 2h
publicclass ListUser implementsAction{ "HDcmIXg&
mqSQL}vR
privatestaticfinal Log logger = LogFactory.getLog ^h"`}[+
?'KL11@R
(ListUser.class); @NNq z
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private UserService userService; q)^Jj?W
\cUC9/
b
private Page page; VB,?Mo}R
4}eepJOn
privateList users; qa0 yg8,<
$>u*}X9
/* Yd#/1!A7u
* (non-Javadoc) {l/-LZ.
* 2kIa*#VOJ
* @see com.opensymphony.xwork.Action#execute() 7Z-O_h3;)@
*/ Vv.|br`;}
publicString execute()throwsException{ 2C9V|[U,
Result result = userService.listUser(page); br":y>=,
page = result.getPage(); {;:/-0s
users = result.getContent(); IHcD*zQ
return SUCCESS; 9mmCp&~Z
} ucG@?@JENm
b"#WxgaF
/** Y}#J4i0b*
* @return Returns the page. d;>#Sxf
*/ U8LtG/
public Page getPage(){ G"Sd@%W(
return page; VrxQc qPr`
} :[hgxJu+
|~X ;1j!
/**
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* @return Returns the users. =[@zF9
*/ oaoU _V
publicList getUsers(){ ?6fnpGX@a
return users; @AIaC-,~]
} M>i9 i-dU
>76\nGO
/** \4-"L>
* @param page OeS\7
* The page to set.
ng_^
*/ y*tZ
!m2Gg
publicvoid setPage(Page page){ 2M68CE
this.page = page; 7]||UuF<
} 'Pn3%&O$
-8j+s}Q
/** LRb{hUt=
* @param users p%*%n3bw
* The users to set. AigS!-
*/ S/ODqL|
publicvoid setUsers(List users){ nysUZB
this.users = users; OVhE??#
} 9/ibWa\.
r?Wk<>%>
/** .xH5fMj,"
* @param userService 83Q4On
* The userService to set. (+FfB"3]
*/ GJtZ&H
publicvoid setUserService(UserService userService){ &'}RrW-s
this.userService = userService; :=/>Vbd: )
} T
QSzx%i2
} [ji#U s:h
b{]z
wpf
Dm-zMCf}Q
I/L_@X<*r
f v9V7
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, Te}8!_ohyC
fDvl/|62{
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 EodQ*{l
'{V0M<O
么只需要: ?Vf o+a,
java代码: N=QfP
[`rba'
glF; eT
<?xml version="1.0"?> 8F&=a,ps[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork qIIv6''5@
h?8]C#6^
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }9W4"e 2)
?l^1 *Q,
1.0.dtd"> zN"J}r:
Y#lk6
<xwork> 7U2J xE
Ooq! 0g
<package name="user" extends="webwork- 8@2OJ =`[
pt?q#EfFJ
interceptors"> _J?
Dq
T3pmVl
<!-- The default interceptor stack name h_T7% #0
%]8qAtV^3j
--> %+K<<iyR|
<default-interceptor-ref |>JS!NM
I
Wu_kx2h
name="myDefaultWebStack"/> 9)gC6IiW
:"IE
<action name="listUser" \8 h;K>=h
eK!V
);
class="com.adt.action.user.ListUser"> IuRmEL_Q_
<param y10h#&k
)_i
qAqkS
name="page.everyPage">10</param> ?Vdia:
<result 52,m:EhL
5wh|=**/
name="success">/user/user_list.jsp</result> (C@~3!AVa
</action> ,]cD
Hqn#yInA7~
</package> \,7}mdQSv
pD01,5/
</xwork> _Gjk;|Sx<I
66I"=:
?}a;}Q6
S4h:|jLUF
*?Kr*]dnLl
.b-f9qc=
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 K/3)g9Z&io
g;8jK8Kh
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。 }woo%N P
mA*AeP_$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N0=ac5
?hWwj6i&
9=V:&.L
HOE_S!N
a8i]]1Blz
我写的一个用于分页的类,用了泛型了,hoho [vHv0"
/Ya_>+oo
java代码: NCk r /#!
=UJ:t Sr
(v}>tb*#`
package com.intokr.util; NX/;+{
:h&fbBH
import java.util.List; 8$ma;U d
h0g:@ae%&
/** $d)ca9
* 用于分页的类<br> 7~GB;1n
* 可以用于传递查询的结果也可以用于传送查询的参数<br> X'`~s}vGO
* \7l-@6'7
* @version 0.01 Tp-l^?O-p
* @author cheng mqAWL:VvQ7
*/ :xh?eN&
public class Paginator<E> { d_)o
privateint count = 0; // 总记录数 ,>eMG=C; g
privateint p = 1; // 页编号 0\@dYPa&C
privateint num = 20; // 每页的记录数 Y))u&*RuT0
privateList<E> results = null; // 结果 `9uB~LY^i
k25WucQ
/** #&m0WI1
* 结果总数 {6c2{@
*/ r!HwXeEn/
publicint getCount(){ JoN\]JL\,
return count; E gal4
} `}lJH i
bBS,-vN
publicvoid setCount(int count){ I*IhwJFl/
this.count = count; 7_mw%|m6@
} {
Q`QX`#
f3H ed
/** Ju3*lk/j-
* 本结果所在的页码,从1开始 1QU:?_\6@t
* c=L2%XPP
* @return Returns the pageNo. Jnna$6G)B
*/ L\&<sy"H
publicint getP(){ Sk:ws&D1u
return p; t0nI ('LX,
} NyVnA
ywb4LKD
/** P~G 1EK|4
* if(p<=0) p=1 ;zIP,PMM
* spGB)k,^
* @param p oA =4=`
*/ qd#sY.|1
publicvoid setP(int p){ p"FW&Q=PN
if(p <= 0) )Lwc
p = 1;
{e[c
this.p = p; +H9 >A0JF
} gOr%!QaF
`S2[5i
/** 8g:;)u4$P
* 每页记录数量 BVr0Gk
*/ GW$.lo1|)
publicint getNum(){ &g.+V/<[
return num; L. EiO({W
} VA9Gb9
%_(H{y_!
/** m^H21P"z
* if(num<1) num=1 mdq;R*`
*/ r; xLP
publicvoid setNum(int num){ {.De4]ANh
if(num < 1) ~5 *5
num = 1; y-j\zK
this.num = num; 1xbK'i:-S
} w7FW^6Zl
Pp|*J^U 4
/** ;Wl+zw
* 获得总页数 *_KFW@bC:
*/ 8S<@"v
publicint getPageNum(){ &3$z4df
return(count - 1) / num + 1; *=wYuJ#
} qqu.EE
C%U`"-%n@7
/** BWM YpZom
* 获得本页的开始编号,为 (p-1)*num+1 ^.hoLwp.
*/ kf;/c}}
publicint getStart(){ s7l;\XBy
return(p - 1) * num + 1; ~",`,ZXQy
} :{ur{m5bX
TzntO9P+
/** 0%Z]h?EYy|
* @return Returns the results. y /BJIQ
*/ xritonG/F
publicList<E> getResults(){ ]_8qn'7
return results; i@B[ eta
} ~>:Z6Le@
h?f>X"*|(
public void setResults(List<E> results){ Ai/b\:V9S
this.results = results; wo3wtx
} +8#_59;x
y8 KX<2s1
public String toString(){ XO9M_*Va
StringBuilder buff = new StringBuilder S_T1y
]a!xUg!S
(); 5 gv/Pq &
buff.append("{"); !
/NG.Wf
buff.append("count:").append(count); J%jB?2
1:o
buff.append(",p:").append(p); ~j#]tElb
buff.append(",nump:").append(num); :T._ba3|
buff.append(",results:").append v\,N 5
,i0b)=!o
(results); ~\cO"(y5:O
buff.append("}"); k~/>b~.c
return buff.toString(); RiTa \
} }->.k/vc
A)~X,
} E%'~'[Q
K3' niGT
p?2Y }9