Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 k"gm;,`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (n.IK/:
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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 Q`'cxx
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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 fA<os+*9i
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分页支持类: !:5'MI@
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java代码: zfI{cMn'J
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package com.javaeye.common.util; 9]ZfSn)
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import java.util.List; q({-C
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publicclass PaginationSupport { VByA6^JR
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publicfinalstaticint PAGESIZE = 30; CfS;F
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privateint pageSize = PAGESIZE; Wf8@B#^{
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privateList items; .p=J_%K}0x
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privateint totalCount; N-2_kjb!
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privateint[] indexes = newint[0]; A#?Cts,M
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privateint startIndex = 0; /mp!%j~
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public PaginationSupport(List items, int $Lbamg->E
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totalCount){ >#&2 5,Q
setPageSize(PAGESIZE); N.Q}.(N0
setTotalCount(totalCount); seAPVzWUU
setItems(items); NQuqM`LSQ
setStartIndex(0); `_1fa7,z
} x%H,ta%
x\ #K2
public PaginationSupport(List items, int p>J@"?%^
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totalCount, int startIndex){ YW~ 9 N
setPageSize(PAGESIZE); xH`
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setTotalCount(totalCount); gzvgXZ1q"
setItems(items); 1'p=yHw
setStartIndex(startIndex); *'H\`@L
}
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public PaginationSupport(List items, int #b)`as?!1
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totalCount, int pageSize, int startIndex){ IIGx+>
setPageSize(pageSize); \Ezcr=0z{j
setTotalCount(totalCount); 3rHn?
setItems(items); sqV~Dw
setStartIndex(startIndex); hg<[@Q%$o
} BUsxgs"),
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publicList getItems(){ 9dAtQwGR"6
return items; pQc-}o"
} {"$[MYi:
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publicvoid setItems(List items){ { Dm@_&
this.items = items; nTtEv~a_n
} T+RC#&>
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publicint getPageSize(){ a
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return pageSize; -'D~nd${
} T4}Wg=UKg
* Wp?0CP
publicvoid setPageSize(int pageSize){ \I}EWI
this.pageSize = pageSize; ^ZS!1%1
} @x!+_z
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publicint getTotalCount(){ k$f2i,7'
return totalCount; (dyY@={q
}
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9I<~t@q5e@
publicvoid setTotalCount(int totalCount){ }!Pty25j
if(totalCount > 0){ o+XQMg
this.totalCount = totalCount; +rSU
int count = totalCount / CSW+UaE
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pageSize; B6Ajcfy
if(totalCount % pageSize > 0) \k"Ct zoX
count++; A*/8j\{n
indexes = newint[count]; LxWd_B
for(int i = 0; i < count; i++){ @'M"c
q
indexes = pageSize * +kE~OdZG
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i; 8*#$3e
} Bvj sl
}else{ Eld[z{n"
this.totalCount = 0; l.g.O>1
} ~9#x=nU:+V
} ;P;c!}:\b
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publicint[] getIndexes(){ Z.Dg=>G]
return indexes; *2vp2xMA@
} aMHC+R1X
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publicvoid setIndexes(int[] indexes){ ~a_X
7
this.indexes = indexes; 6:; >id${
} Q}<QE:-&E
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publicint getStartIndex(){ W|zPV`
return startIndex; $%31Gk[I
} UmGKj9u
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publicvoid setStartIndex(int startIndex){ j%bC9UkE3
if(totalCount <= 0) /#@tv~Z^
this.startIndex = 0; yk5K8D[tV
elseif(startIndex >= totalCount) C$C>RYE?.
this.startIndex = indexes m0h,!
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[indexes.length - 1]; LA2/<:
elseif(startIndex < 0) &hL2xx=
this.startIndex = 0; (^g XO
else{ A! HJ
this.startIndex = indexes Kj3Gm>B<y
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[startIndex / pageSize]; oUN\tOiS+
} "sDs[Lcq
} \~Z%}$ =
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publicint getNextIndex(){ ^^B_z|;Aa
int nextIndex = getStartIndex() + Y[R>?w
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pageSize; eu_ZsseZ
if(nextIndex >= totalCount) ZbdGI@
return getStartIndex(); CP%^)LX *
else <`; {gX1
return nextIndex; (&v|,.c^)1
} d-tg^Ot#
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publicint getPreviousIndex(){ _JNYvngm
int previousIndex = getStartIndex() - yx4pQL7
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pageSize; )b2O!p
if(previousIndex < 0) jg{2Sxf!c
return0; yOKzw~;0%
else .S/zxf~h
return previousIndex; 3^y<Db
} Z~-N'Lt{
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} ?vAhDD5
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抽象业务类 vo*oCfm
java代码: `Z5dRLrd
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/** Ny/eYF#
* Created on 2005-7-12 .43cI(
*/ M")/6 PH8
package com.javaeye.common.business; ;l @lA)i
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import java.io.Serializable; 6z6\xkr
import java.util.List; pXN'vP
#(Gz?kGAH`
import org.hibernate.Criteria; *xsBFCRU
import org.hibernate.HibernateException; p!uB8F
import org.hibernate.Session; R*lq7n9
import org.hibernate.criterion.DetachedCriteria; nC%qdzT
import org.hibernate.criterion.Projections; C<(oaeQY
import YOGj__:
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org.springframework.orm.hibernate3.HibernateCallback; Gvh"3|u?z
import /P TRe5-7
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org.springframework.orm.hibernate3.support.HibernateDaoS Mkk.8AjC|
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upport; a4 N f\7
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import com.javaeye.common.util.PaginationSupport; F5/,S
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public abstract class AbstractManager extends 76<mP*5
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HibernateDaoSupport { _Q
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privateboolean cacheQueries = false; t $Rc
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privateString queryCacheRegion; 1Pw1TO"Z
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publicvoid setCacheQueries(boolean ;zD4#7=
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cacheQueries){ Q#H"Se
this.cacheQueries = cacheQueries; ~).D\Q\
} ycc G>%>r
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publicvoid setQueryCacheRegion(String H2Wlgt
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queryCacheRegion){ j+ -r(lZ
this.queryCacheRegion = J({D~
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queryCacheRegion; /R=MX>JA;
} r W[;3yMf
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publicvoid save(finalObject entity){ ~BJE~
getHibernateTemplate().save(entity); =NC??e {
} *4`5&) `
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publicvoid persist(finalObject entity){ |w{Qwf!2
getHibernateTemplate().save(entity); MAFdJ+n#
} ~KMah
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publicvoid update(finalObject entity){ j`RG Moq
getHibernateTemplate().update(entity); yFDeYPZP
} Z)E)-2U$@
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publicvoid delete(finalObject entity){ wT":
getHibernateTemplate().delete(entity); a!: N
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} V)/J2 -w
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publicObject load(finalClass entity, q q&U)-`
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finalSerializable id){ qNj?Rwc
return getHibernateTemplate().load HBE[q#
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(entity, id); \N0vA~N.
} uWdF7|PN7
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publicObject get(finalClass entity, <.4(#Ebd
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finalSerializable id){ <F0^+Pf/
return getHibernateTemplate().get Vl5>o$G|<.
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(entity, id); n
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} $]E+E.P
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publicList findAll(finalClass entity){ z&d.YO_W
return getHibernateTemplate().find("from @y;VV*
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" + entity.getName()); 8N'hG,
} 'A:Y&w"r
{ %X2K
publicList findByNamedQuery(finalString tpcB}HUv
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namedQuery){ IXa~,a H71
return getHibernateTemplate *GE6zGdN
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().findByNamedQuery(namedQuery); Nz`8)Le
} T"Y#u
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publicList findByNamedQuery(finalString query, H;nzo3x
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finalObject parameter){ *Sj)9mp
return getHibernateTemplate 06.%9R{
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().findByNamedQuery(query, parameter); La1:WYt
} qK%N{ro[{?
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publicList findByNamedQuery(finalString query, _j, Tc*T
*P*~CHx>
finalObject[] parameters){ :[n~(~7?
return getHibernateTemplate ,nteIR'??
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().findByNamedQuery(query, parameters); K _VIk'RB
} ^R@)CIQ
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publicList find(finalString query){ pE<a:2J
return getHibernateTemplate().find .2@T|WD!Ah
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(query); JE9v+a{7
} ZNw|5u^N
t^":.}[Q
publicList find(finalString query, finalObject D|ze0A@
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parameter){ /(s |'"6
return getHibernateTemplate().find Q"FN"uQ}x
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(query, parameter); M8WjqTq
} RG45S0Ygj
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public PaginationSupport findPageByCriteria }kmAUaa,Z
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(final DetachedCriteria detachedCriteria){ I*a@_EO
return findPageByCriteria #(614-r/
p+=zl`\=|
(detachedCriteria, PaginationSupport.PAGESIZE, 0); k(H]ILL
} md{nHX&
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public PaginationSupport findPageByCriteria ?pEPwc
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(final DetachedCriteria detachedCriteria, finalint g]&fyB#
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startIndex){ xFp$JN
return findPageByCriteria zy$jTqDH
m=9b/Nr4
(detachedCriteria, PaginationSupport.PAGESIZE, RM_%u=jC
9)tb=
startIndex); _\+]/rY9o
} |k6+-
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public PaginationSupport findPageByCriteria J8Wits]A]$
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(final DetachedCriteria detachedCriteria, finalint Nxe1^F33
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pageSize, dM^EYW
finalint startIndex){ Cty{
return(PaginationSupport) *Ze0V9$'
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getHibernateTemplate().execute(new HibernateCallback(){ [&99#7B
publicObject doInHibernate x@43ZH_
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(Session session)throws HibernateException { %_s)Gw&sq
Criteria criteria = <MG&3L.[
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detachedCriteria.getExecutableCriteria(session); -hnNaA
int totalCount = G)s.~ T
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((Integer) criteria.setProjection(Projections.rowCount "|(.W3f1
|Yw k
()).uniqueResult()).intValue(); 6inAnC@I
criteria.setProjection >C_G~R
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(null); hev;M)t
List items = $rW(*#C
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criteria.setFirstResult(startIndex).setMaxResults bh5D}w
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(pageSize).list(); }d}sC\>U
PaginationSupport ps = %N&.B
[#Apd1S_
new PaginationSupport(items, totalCount, pageSize, vai w*?jV
$#f_p-N
startIndex); z**2-4 z
return ps; JqO1 a?H
} 3\}u#/Vb
}, true); |qe;+)0>K
} &X:;B'
,(q]
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public List findAllByCriteria(final +r"}@8/\1
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DetachedCriteria detachedCriteria){ }y*D(`
return(List) getHibernateTemplate Zfk]Z9YO
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().execute(new HibernateCallback(){ "[7-1} l
publicObject doInHibernate r}qDvC D
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(Session session)throws HibernateException { O0jOI3/P%
Criteria criteria = =$4I}2
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detachedCriteria.getExecutableCriteria(session); W2rd[W
return criteria.list(); 55s5(]`d
} [c=P)t7
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}, true); P6kDtUXF
} 3);P!W4>
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public int getCountByCriteria(final !`N:.+DT
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DetachedCriteria detachedCriteria){ ZMlBd}H
Integer count = (Integer) OR6vA5J
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getHibernateTemplate().execute(new HibernateCallback(){ eEBNO*2
publicObject doInHibernate OF`J{`{r
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(Session session)throws HibernateException { c=+%][21
Criteria criteria = V~*>/2+
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detachedCriteria.getExecutableCriteria(session); G@Z%[YNw
return .n8O 3V
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criteria.setProjection(Projections.rowCount @P~%4:!Hr
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()).uniqueResult(); *K_8=TIA*
} >ye.rRZd`
}, true); M`K]g&57hL
return count.intValue(); mW!n%f
} <eMqg u
} V-#JV@b
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用户在web层构造查询条件detachedCriteria,和可选的 }0\SNpVN
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @2.
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PaginationSupport的实例ps。 x[};x;[ZE
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ps.getItems()得到已分页好的结果集 #tA9`!
ps.getIndexes()得到分页索引的数组 5ZkR3/h e
ps.getTotalCount()得到总结果数 >}F$6KM
ps.getStartIndex()当前分页索引 sXEIC#rq
ps.getNextIndex()下一页索引 OEl;R7aOB&
ps.getPreviousIndex()上一页索引 ?xUl_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >;Oa|G
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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@9Tw2Y
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一下代码重构了。 oy
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我把原本我的做法也提供出来供大家讨论吧: W=A0+t%XC
aNKw.S>
首先,为了实现分页查询,我封装了一个Page类: yNfj-wM
java代码: yLLA:5Q1
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/*Created on 2005-4-14*/ !I1p`_(_7
package org.flyware.util.page; =7TWzUCO#
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/** b+:mV7eX
* @author Joa
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* ZiY2N*,VO
*/ 7Z:3xb&>
publicclass Page { 9\?&u_ U"
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/** imply if the page has previous page */ @F(er
privateboolean hasPrePage; :tO?+1
!]s=9(O
/** imply if the page has next page */ <<S4l~"o
privateboolean hasNextPage; U%r{{Q1
!-T#dU
/** the number of every page */ [V_mF
privateint everyPage; Q(N'Oj:J
W (TTsnnx
/** the total page number */ +&"W:Le:
privateint totalPage; ApSseBhh
+7OE,RoQ
/** the number of current page */ U7fpaxc-
privateint currentPage; `2U,#nZ 4
o/,%rA4
/** the begin index of the records by the current jo"+_)]
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query */ m8L %!6o
privateint beginIndex; "K>!+<
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/** The default constructor */ /oe0
public Page(){ 6T~+vT
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} 9VaSCB
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/** construct the page by everyPage q{*[uJ}Xc"
* @param everyPage /Tl ybSC1
* */ )N{PWSPs
public Page(int everyPage){ 8z=o.\@
this.everyPage = everyPage; G2[2y-Rv
} 0j;|IU\
HWoMzp5="3
/** The whole constructor */ &flcJ`
public Page(boolean hasPrePage, boolean hasNextPage, ~O./A-l
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int everyPage, int totalPage, A+Je?3/.
int currentPage, int beginIndex){ ocW`sE?EED
this.hasPrePage = hasPrePage; 9|>y[i
this.hasNextPage = hasNextPage; 3H"F~_H
this.everyPage = everyPage; p(4Ek"
this.totalPage = totalPage; G@ybx[_[@
this.currentPage = currentPage; 3S^Qo9S
this.beginIndex = beginIndex; YA8/TFu<_
} Tz&cm=
BI#(L={5
/** ?b^<Tny
* @return
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* Returns the beginIndex. )CL/%I,^
*/ 3 5-FD{
publicint getBeginIndex(){ *Z"Kvj;>u
return beginIndex; /Jk.b/t.*S
} %iV\nFal>
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/** z5:3.+M5
* @param beginIndex 6x;"T+BSSS
* The beginIndex to set. ?1]B(V9nBq
*/ ,aWfGh#$
publicvoid setBeginIndex(int beginIndex){ nYRD>S?uz
this.beginIndex = beginIndex; 8v;T_VN
} N/^[c+J[E
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>,
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/** |@-y+vbA*
* @return *OE>gg&?Nh
* Returns the currentPage. &E
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*/ S;vZXgyN?
publicint getCurrentPage(){ |("5 :m
return currentPage; Z[j-.,Qu
} 8{Svax(
tK <)A)
/** 6B?1d
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* @param currentPage }>j1j^c1='
* The currentPage to set. V|0UwS\n
*/ IZ4jFgpR
publicvoid setCurrentPage(int currentPage){ / dn]`Ge)
this.currentPage = currentPage; P|)SXR
} t;ga>^NA"
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/** p/s5[>N
* @return JeCEj=_Z
* Returns the everyPage. WHF:>0B
*/ Fn%:0j
publicint getEveryPage(){ Md m(xUs
return everyPage;
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} a-DE-V Uls
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/** Nb{oH +$b
* @param everyPage qm}7w3I^
* The everyPage to set. 55|$Imnf
*/ g(;ejKSR
publicvoid setEveryPage(int everyPage){ N=L
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this.everyPage = everyPage; 7~`6~qg.
}
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/** ')FNudsC
* @return PwNLJj+%
* Returns the hasNextPage. q+G1#5
*/ vqxTf)ys
publicboolean getHasNextPage(){
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return hasNextPage; -)<Nd:A
} !8s:3]
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/** G6Fg<g9:
* @param hasNextPage 86} rz
* The hasNextPage to set. ;j_#,Da9<
*/ %F/tbXy{
publicvoid setHasNextPage(boolean hasNextPage){ 'Ph;:EMj
this.hasNextPage = hasNextPage; )I}G:bBa
} If#7SF)n'
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/** n2O7n@8
* @return C,z]q$4
* Returns the hasPrePage. 1Q;`<=
*/ )DLK<10
publicboolean getHasPrePage(){ y! 1NS
return hasPrePage; P?uKDON
} V+K.'
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^@
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/** {DO9{96w4
* @param hasPrePage 0UB'6wRVo
* The hasPrePage to set. NAocmbfNz
*/ -jw=Iyv
publicvoid setHasPrePage(boolean hasPrePage){ "7
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this.hasPrePage = hasPrePage; ]V]o%onW
} :{6[U=O
5Q'R5]?h
/** =UP)b9*h
* @return Returns the totalPage. Gsh2
* 3a S>U #
*/ -T(V6&'Qi
publicint getTotalPage(){ UX9o
return totalPage; ";. 3+z
}
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/** t-Fl"@s
* @param totalPage wIiT
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* The totalPage to set. V)Xcn'h
*/ MdfkC6P
publicvoid setTotalPage(int totalPage){ Te13Af~
this.totalPage = totalPage; gy[uqm_ T
} \
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T
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} ixkg,
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G j:|
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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 ZtT`_G&
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个PageUtil,负责对Page对象进行构造: ={oO9.9
java代码: X[[=YCi0
m1hf[cg
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/*Created on 2005-4-14*/ , $=V
package org.flyware.util.page; !14z4]b
0.5_,an3
import org.apache.commons.logging.Log; m4
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import org.apache.commons.logging.LogFactory; BMW4E 5
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/** RinRQd
* @author Joa btE+.V
* / u{r5`4
*/ M>#{~zr
publicclass PageUtil { >j?uI6Uw
G#C)]4[n
privatestaticfinal Log logger = LogFactory.getLog hU{%x#8}lK
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(PageUtil.class); V+q RDQ
(
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/** l]Sui_+ZU
* Use the origin page to create a new page 8K/lpqw
* @param page D.e*IP1R
* @param totalRecords 2S4z$(x3
* @return V_QVLW
*/ k|D!0^HE[
publicstatic Page createPage(Page page, int VGq]id{*$
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o]
totalRecords){ 2P}RZvUd
return createPage(page.getEveryPage(), #wyS?FP-
UTt#ltun ?
page.getCurrentPage(), totalRecords); Id0F2 [
} ;a`X|N9
~83P09\T%
/** 1DP)6{x
* the basic page utils not including exception @6SSk=9_S
ik*_,51Zj
handler ,L;vN6~
* @param everyPage ;<A/e
* @param currentPage -G 'lyH
* @param totalRecords e{,/
* @return page mI%/k7:sf
*/ NsHveOK1.
publicstatic Page createPage(int everyPage, int QFYy$T+W
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currentPage, int totalRecords){ I'C,'
everyPage = getEveryPage(everyPage); :Eyv= =
currentPage = getCurrentPage(currentPage); 5,Y2Lzr
int beginIndex = getBeginIndex(everyPage, K;PpS*!
M=A9ax
currentPage); %U7B0-
int totalPage = getTotalPage(everyPage, hz%IxI9
ap~Iz
totalRecords); xTMTkVa+B
boolean hasNextPage = hasNextPage(currentPage, [)A#9L~s=
fLAF/#\2
totalPage); U:9vjY
boolean hasPrePage = hasPrePage(currentPage); M\f0
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s|T7)PgR
returnnew Page(hasPrePage, hasNextPage, M6sDtL9l
everyPage, totalPage, gOM`I+CwT
currentPage, bB-v ar
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beginIndex); #Au&2_O
} rYQ@"o0/Y
d
]
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privatestaticint getEveryPage(int everyPage){ `uHpj`EU
return everyPage == 0 ? 10 : everyPage; G
m! ]
} Tt|6N*b'
*
U4:K@y
privatestaticint getCurrentPage(int currentPage){ sBnPS[Oo
return currentPage == 0 ? 1 : currentPage; beE%%C]X
} Rjl __90
8A .7=C' z
privatestaticint getBeginIndex(int everyPage, int S+Yg!RrNqj
;g
jp&g9Q
currentPage){ 6,1|y%(f
return(currentPage - 1) * everyPage; ".?{Y(~
} (K6StNtN
]s@8I2_
privatestaticint getTotalPage(int everyPage, int #7h fEAk
V&H8-,7z
totalRecords){ (02(:;1
int totalPage = 0; w>_EM&r6~u
zP}v2
if(totalRecords % everyPage == 0) 0)V-|v`
totalPage = totalRecords / everyPage; {2^@jD
else 9AzGk=^
totalPage = totalRecords / everyPage + 1 ; ,r;d {
]H~,K ]@.
return totalPage; /H@")je
} v!A|n3B]p
{1|7N
GQ
privatestaticboolean hasPrePage(int currentPage){ ZF(=^.gc
return currentPage == 1 ? false : true; {C6;$#7P
} UE w3AO
)fc"])&8
privatestaticboolean hasNextPage(int currentPage, :w%bw\}
q)+n2FM
int totalPage){ :OaQq@V
return currentPage == totalPage || totalPage == 1o 78e2B
:0/o?'s
0 ? false : true; W%K8HAP "
} `|Z@UPHzG
'/g+;^_cB
zqr%7U
} D
;$+] 2
Zb;$ZUWQX
O/oYaAlFF@
Z8 %\v(L
TR_oI<xB2
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。 ItE~MJ5p
a' o8n6i
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 }p?V5Qp
Vj`s_IPY
做法如下: 5G;^OI!g
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 $ywh%OEH
+N:6wZ7<f
的信息,和一个结果集List: xGv,%'u\
java代码: G;c0
6RQCKN)
k+GnF00N^8
/*Created on 2005-6-13*/ bI6wE'h
package com.adt.bo; <SdJM1%Qo
.eB"la|d
import java.util.List; {eN{Zh5"
FKnQwX.0
import org.flyware.util.page.Page; <D;Q8
bu]Se6%}
/** X3iRR{< @
* @author Joa 4Olv8nOe<
*/ aw%vu
publicclass Result { )"jn{%/t
]{+M>i[
private Page page; [k7N+W8
fUKdC\WL
private List content; LY:?OGh
?mfWm{QTt
/** 8!Mzr1:
* The default constructor ,xe@G)a
*/ %aE7id>v6
public Result(){ (`.qG
&6p
super(); G:C6`uiy`
} 8kM0
<ZC^H
/** '#
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* The constructor using fields !XA%[u
* !2U7gVt"*
* @param page Mth`s{sATa
* @param content zn;Hs]G
*/ $o$Ev@mi
public Result(Page page, List content){ jsi#l
this.page = page; c$<O0dI
this.content = content; To{G#QEgG
} xc<eU`-'b
G[<[#$(
/** Sb9=$0%\
* @return Returns the content. f(s3TLM
*/ K-k.=6mS
publicList getContent(){ ],}afa!A
return content; wt=>{JM
} eTRx 6Fri(
<Bb<?7q$ld
/** fy=C!N&/
* @return Returns the page. p2c=;5|/Q
*/ $N+{r=
public Page getPage(){ hB$Y4~T%
return page; m/c&/6nk
} 9_A0:S9Z
/xm#:+Sc
/** :;*#Qh3"
* @param content kPX2e h
* The content to set. pM'IQ3N
*/ 5v>{Z0TE[6
public void setContent(List content){ qwNKRqT
this.content = content; H^PqYLjN
} _
kSPUP5
+V+*7s%fL
/** r~G]2*3
* @param page h[ZN >T
* The page to set. A;WwS?fyQ
*/ [T[9*6Kt
publicvoid setPage(Page page){
6:@t=C
this.page = page; e(; `9T
} 'UvS3]bSYW
} BUA6(
n:^"[Le
zhX`~){N6
HMS9y%zl/
:OQ:@Yk
2. 编写业务逻辑接口,并实现它(UserManager, $,QpSK`9i
E4v_2Q
-w
UserManagerImpl) #u<oEDQ
java代码: 51ajE2+X&
U_}A{bFG
sAD P~xvU
/*Created on 2005-7-15*/ K)Xs L
package com.adt.service; W]yClx \
+G!jKta7B
import net.sf.hibernate.HibernateException; r0g/ :lJi
97]a-)SA
import org.flyware.util.page.Page; S-LZ(o{ZL
SC
$`
import com.adt.bo.Result; >SxZ9T|%
m]=oaj@9
/** iy.%kHC
* @author Joa @
Zgl>
*/ ULNAH`{D
publicinterface UserManager { DNW2;i<hsz
e:GgA
public Result listUser(Page page)throws Id.Z[owC`Y
rxy{a
HibernateException; |:e|~sism
H?`)[#
} +F7<5YW&(
3?*M{Y|
s*)41\V0
xf^<ec
)p!*c,
java代码: a:-)+sgHw
aZawBU.:
yA?ENAM
/*Created on 2005-7-15*/ NO+
55n
package com.adt.service.impl; {n'qKurxY
n(Q\',C
import java.util.List; sR>`QIi(a
m,@1LwBH
import net.sf.hibernate.HibernateException; F[7Kw"~J
d@D;'2}Yc
import org.flyware.util.page.Page; ,\S pjE
import org.flyware.util.page.PageUtil; 0 .FHdJ<
1~R$$P11[9
import com.adt.bo.Result; R*Xu(89
import com.adt.dao.UserDAO; sMz^!RX@
import com.adt.exception.ObjectNotFoundException; ?}=-eJ(7e
import com.adt.service.UserManager; dDqr
B-G
*1Ut}
/** CCW%G,$U9
* @author Joa )@<HCRQ'q
*/ pyg!rf-
publicclass UserManagerImpl implements UserManager { YH'$_,8peM
{HIR>])o
private UserDAO userDAO; EREolCASb
+-H}s`
/** Gq0]m
* @param userDAO The userDAO to set. @@%i(>4Z
*/ j Ne(w<',P
publicvoid setUserDAO(UserDAO userDAO){ wUK7um
this.userDAO = userDAO; o9m
} tIGVB+g{F
w\o)bn
/* (non-Javadoc)
b(}Gm@#
* @see com.adt.service.UserManager#listUser ^nHB1"OCV
S(>@:`=
(org.flyware.util.page.Page) })o~E
*/ q:Y6fbt<7
public Result listUser(Page page)throws CYPazOfj
(2 T#/$
HibernateException, ObjectNotFoundException { +9CEC1-l
int totalRecords = userDAO.getUserCount(); *%T)\\H2
if(totalRecords == 0) I #M%%5e
throw new ObjectNotFoundException "K|)<6J
@,x_i8
("userNotExist"); 6%gB
E
page = PageUtil.createPage(page, totalRecords); }A4nJ>`tq
List users = userDAO.getUserByPage(page); i\=z'
returnnew Result(page, users); x7P([^i
} Sc1+(z
>
$w^%I
} Q;$
9qOF
W NwJM
s;fVnaqG:
eeW' [
LbJtpwz>z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0$eyT-:d
~9JW#HHzn
询,接下来编写UserDAO的代码: |'V DI]p&
3. UserDAO 和 UserDAOImpl: O!+nF]V4f
java代码: ~lzdbX
lQV|U;~D
_ yfdj[Ot`
/*Created on 2005-7-15*/ X5uS>V%/
package com.adt.dao; ] vC=.&]
1Yc%0L(
import java.util.List; hD nM+4D
_\
.
import org.flyware.util.page.Page; <u/a`E?
_4P;+Y
import net.sf.hibernate.HibernateException; Q7,EY /
xn(+G$m
/** b!i`o%Vb
* @author Joa e#>tM
*/ T*h!d(
publicinterface UserDAO extends BaseDAO { D4< -8
ss?]
publicList getUserByName(String name)throws m"lE&AM64p
UF@IBb}0
HibernateException; #*!+b
(Ij0AeJ#
publicint getUserCount()throws HibernateException; F,*2#:Ki
28nmQ
publicList getUserByPage(Page page)throws Gs[Vu@*
cCM
j\H@
HibernateException; UdT&cG
/ Zo~1q
} P3'2IzNw
+"]oc{W!
G/v|!}?wG
u-m %=2
Q`H#
fS~
java代码: '5'3_vM
No:^hY:F8
3c c1EQ9
/*Created on 2005-7-15*/ f?,-j>[.=f
package com.adt.dao.impl; ~O \}/I28
?n!lUr$:y
import java.util.List; 4\p$4Hs}
\% }raI;Y@
import org.flyware.util.page.Page; !G7h9CF|{
Ci;h
import net.sf.hibernate.HibernateException; >@^<S_KVh
import net.sf.hibernate.Query; N<9w{zIK(
"Dyym<J
import com.adt.dao.UserDAO; @ru<4`h
|2z}Xm5\
/** {tPnj_|n<
* @author Joa m"n.Dz/S
*/ \CcmePTN#x
public class UserDAOImpl extends BaseDAOHibernateImpl (nGkZ}p
i-`,/e~XT
implements UserDAO { HtxLMzgz<<
brb[})}
/* (non-Javadoc) ya:sW5fk
* @see com.adt.dao.UserDAO#getUserByName f%c06Un=
"X`RQ6~]>
(java.lang.String) BsKbn@'uC
*/ p~h4\.*`
publicList getUserByName(String name)throws t) LU\!
Q/p(#/y#b
HibernateException { IWQ&6SDW$z
String querySentence = "FROM user in class Bb~5& @M|N
:3v9h^|+
com.adt.po.User WHERE user.name=:name"; L#n}e7Y9
Query query = getSession().createQuery PC|'yAN:
GE@uOJ6H
(querySentence); qk&gA}qF
query.setParameter("name", name); (#oYyM]
return query.list(); >;,gGH
} @d&g/ccMxd
iAK/d)bq
/* (non-Javadoc) 5:c;RRn
* @see com.adt.dao.UserDAO#getUserCount() B~?c3:6
*/ ;d4y{
publicint getUserCount()throws HibernateException { Vc| NL^
int count = 0; *%X.ym'
String querySentence = "SELECT count(*) FROM T8U[xu.>
=^Th[B
user in class com.adt.po.User"; q-YL]PgV
Query query = getSession().createQuery x@Y|v@}BE
gV|Y54}T
(querySentence); D i+4Eb
count = ((Integer)query.iterate().next bhYU5I 9
ha5e(Hj?
()).intValue(); glx2I_y
return count; ]oEQ4
} I] jX7.fx
B%fU'
/* (non-Javadoc) k52QaMKa~A
* @see com.adt.dao.UserDAO#getUserByPage &3I$8v|!?
c}%es=@
(org.flyware.util.page.Page) Ah (iE
*/ e8{^f]5
publicList getUserByPage(Page page)throws G]-%AO{K
7%4.b7Q
HibernateException { 45)D+
String querySentence = "FROM user in class };rm3;~ eg
)6=gooe]
com.adt.po.User"; GMdI0jaG#
Query query = getSession().createQuery AFGwT%ZD
KSc~GP_
(querySentence); j{)~QD ?
query.setFirstResult(page.getBeginIndex()) jB!W2~Z
.setMaxResults(page.getEveryPage()); Y''6NGf
return query.list(); a%E8(ms37y
} M6_-f ;.
r{S=Z~J
} =U NT.]
)pS8{c)E
g2=}G <*0
\-OC|\{32
D"cKlp-I6|
至此,一个完整的分页程序完成。前台的只需要调用 D^u\l
kon5+g9q
userManager.listUser(page)即可得到一个Page对象和结果集对象 xQo~%wW,?
_IxamWpX$
的综合体,而传入的参数page对象则可以由前台传入,如果用 tq&Yek>C
\45(#H<$
webwork,甚至可以直接在配置文件中指定。 >ZeEX,N
,T$r9!WTM
下面给出一个webwork调用示例: c;wA
java代码: MqdB\OW&
-2 xE#r
&DLhb90
/*Created on 2005-6-17*/ ~M*gsW$
package com.adt.action.user; 1"O&40l
4)^vMG&
import java.util.List;
RL*]g*
TT7PQf >
import org.apache.commons.logging.Log; P?J kP
import org.apache.commons.logging.LogFactory; /PqUXF
import org.flyware.util.page.Page; :G 5C ]'t
6R2uWv
import com.adt.bo.Result; 4%7s259%
import com.adt.service.UserService; 4.Z(:g
import com.opensymphony.xwork.Action; ~^$MA$ /p
g\&2s,
/** =Z`0>R`
* @author Joa >A($8=+#x
*/ U
Du~2%
publicclass ListUser implementsAction{ HN68!v}C|
cy3M^_5B<
privatestaticfinal Log logger = LogFactory.getLog fK_~lGY(
f=m/
-mAA
(ListUser.class); o?wt$j-
l3p3tT3+
private UserService userService; kOipH |.x
K/|
private Page page; TsD;Kl1
A"4@L*QV
privateList users; 3ji:O T
+
|C=ZU
/* ^f|<R8 `
* (non-Javadoc) -k{Jp/-D
* L\L"mc|O
* @see com.opensymphony.xwork.Action#execute() 7|Dn+=
*/ lw[<STpD;
publicString execute()throwsException{ ([KN*OF
Result result = userService.listUser(page); XG&K32_fs
page = result.getPage(); X NE+(Bt
users = result.getContent(); }0;Sk(B>
return SUCCESS; C[8Kl D
} \Y e%o}.{
iBoEZEHjw
/** <hv7s,i
* @return Returns the page. lFfXWNb
*/ .C= I^
public Page getPage(){ e$|VG*
d
return page; o&$hYy"<.L
} fHfY}BQS
y5u\j{?Te
/** A1-qtAO]
* @return Returns the users. FT.@1/ )
*/ ~`R1sSr"
publicList getUsers(){ G{o+R]Us
return users; j=ihbR^]Tl
} 5v9uHxy
S}7>RHe
/** RmO yGSO
* @param page 4seciz0?
* The page to set. f#P_xn&et
*/ x?L hq2
publicvoid setPage(Page page){ V]c5
Z$Bd
this.page = page; }V]eg,.BJ
} z-@-O
J+Bdz6lt
/** IN^_BKQt
* @param users V@Wcb$mgk
* The users to set. uV~e|X
"9s
*/ :woa&(wN;1
publicvoid setUsers(List users){ <Wy>^<`
this.users = users; *]x_,:R6Ow
} a)S7}0|R
C) .2gQ
G
/** ce' TYkPM
* @param userService 0JXqhc9'
* The userService to set. TpP8=8_Lh
*/ <AUWby,"
publicvoid setUserService(UserService userService){ l!IGc:
this.userService = userService; ``9 GY
} ^,V[nfQR
} xvDI 4x&
uvB1VV4
Y=Hz;Ni
xR908+>5
:3?|VE F
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, ~ E *d G
z+3 9ee
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 R2LK.bTVn
Y&~M7TY b
么只需要: s'L?;:)dyB
java代码: a+?~;.i~
'm O2t~n
)(bxpW
<?xml version="1.0"?> j} RzXJ~t
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork YKs4{?vw
1V%'.l9
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Wsm`YLYkt!
bGv4.:)
1.0.dtd"> p4>,Fwy2
Qb`C)Nh:
<xwork> -3hCiKq
Q)^g3J
<package name="user" extends="webwork- .mPg0
rkYjq4Z@
interceptors"> B*@6xS[IL
PayV,8
<!-- The default interceptor stack name Fe$/t(
@ls.&BHUP
--> jO)&KEh
<default-interceptor-ref daX*}Ix
1r571B*O
name="myDefaultWebStack"/> cwynd=^nC
~O4|KY
<action name="listUser" sR*Nq5F#9
'[Gm8K5
class="com.adt.action.user.ListUser"> Fu)Th|5GZ
<param -&Gfh\_NW
hz)9"B\S
name="page.everyPage">10</param> f\K#>u*
Q
<result \0AiCMX[
-x'e+zT
name="success">/user/user_list.jsp</result> aqr!oxn?t
</action> >o[|"oLO
L2|aHI1'l
</package> 0*7*RX
8A{6j
</xwork> 7X'y>\^w^>
;NsO
vWY(% Q,
r4eUZ .8R
RP`
`mI
?_ RYqolz
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ek)Xrp:2
6/2v
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 x /
XkD]Hq
R^P_{_I*"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8$}OS-
Oif,|:
Vxh.<b6&'
[Ox(.
Lko`F$5X
我写的一个用于分页的类,用了泛型了,hoho p|VcMxT9-
)5yj/0oT
java代码: 4}yE+dRUK:
G)7)]yBL
9
5 H?{
package com.intokr.util; ,Y!zORv<7
@ajM^L!O
import java.util.List; 9]$`)wZ
Y}.Ystem
/** /iC_!n u
* 用于分页的类<br> WE.Tuo5L
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5$Kf]ZP
* T*P+Fh"
* @version 0.01 wO!u!I
* @author cheng
BGqa-d
*/ CC8k&u,
public class Paginator<E> { aRwnRii
privateint count = 0; // 总记录数 f7+Cz>R
privateint p = 1; // 页编号 r!K|E95oj9
privateint num = 20; // 每页的记录数 &!1}`4$[T
privateList<E> results = null; // 结果 ;KcFy@ 6q5
?`P2'i<b
/** F6dr
* 结果总数 gdi`x|0
*/ yQ[u3tI
publicint getCount(){ w0Ij'=:
return count; Y@} FL;3
} D4Sh9:\
uva\0q
publicvoid setCount(int count){ E`)Qs[?Gk
this.count = count; dlD}Ub
} :p-Y7CSSu
iJP{|-h
/** Z"tQpJg
* 本结果所在的页码,从1开始 qrDcL>Hrn
* T[2}p=<%
* @return Returns the pageNo. )%mAZk-*;^
*/ 3{3/: 7
publicint getP(){ `clB43i
return p; .~`Y)PON
} !F7: i
)N)ljA3]
/** rYGRz#:~+
* if(p<=0) p=1 _T]>/}}p
* Q]\j>>
* @param p IJPgFZ7
*/ se,Z#H
publicvoid setP(int p){ 9}
*$n&B
if(p <= 0) ~3=2=Uf
p = 1; /DU*M,
this.p = p; JEHK:1^
} qG9qN.|dC
ma]?
)1<{
/** 0Hcbkep9D
* 每页记录数量 n\= (S9
*/ 4VFc|g
publicint getNum(){ OCW+?B;
return num; Qp!J:YV
} o}~3JBnT
yWHne~!
/** sXB+s
* if(num<1) num=1 NG9vml
*/ ;0j*>fb\q7
publicvoid setNum(int num){ k/#>S*Ne
if(num < 1) u(hC^T1
num = 1; 263*: Y
this.num = num; btQet.
} N!m%~kS9k<
T
% /
/** ;3UvkN
* 获得总页数 3; y_mg
*/ E@pFTvo
publicint getPageNum(){ F=i!d,S
return(count - 1) / num + 1; NI\H
\#bJ
} h{/ve`F>@
x,1=D~L}
/** A&l7d0Z^j5
* 获得本页的开始编号,为 (p-1)*num+1 \n0gTwiO%
*/ B01^oYM}
publicint getStart(){ d_T<5Hin
return(p - 1) * num + 1; e?<D F.Md+
} "Ot{^_e
MPvWCPB
/** /{we;Ut=g
* @return Returns the results. KjYDFrR4
*/ ,?y7,nb
publicList<E> getResults(){ }vD;DSz:
return results; GP]TnQ<*;
} c[{UI
vYzVY\
public void setResults(List<E> results){ `M rBav
this.results = results; gj;@?o0
} wOcg4HlW
)E`+BH
public String toString(){ oKiD8':
StringBuilder buff = new StringBuilder q?iCc c
!4B_$6US
(); o2}N=|&
buff.append("{"); sR!+d:LJ4
buff.append("count:").append(count); Tc_do"uU
buff.append(",p:").append(p); 6ZksqdP8
buff.append(",nump:").append(num); :#SNpn=@
buff.append(",results:").append A^g>fv
hVZo"XUb
(results); JUU&Z[6J
buff.append("}"); ;]@exp5
return buff.toString(); V{$Sfmey
} czS7-Hh@
fq(5Lfe}
} ITc`]K
8[HZ@@
NL-_#N$