Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 oz(V a!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 E({W`b~_f
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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 =ILE/pC-|
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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 fD<9k
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分页支持类: UMN3.-4K#
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java代码: AM4lAq_
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package com.javaeye.common.util; #)&kF+
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import java.util.List; 9?5'>WO
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publicclass PaginationSupport { ?6;9r[ p
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publicfinalstaticint PAGESIZE = 30; }w{6Ua
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privateint pageSize = PAGESIZE; >?/Pl"{b
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privateList items; z']TRjDbT
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privateint totalCount; 0x&-/qce6W
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privateint[] indexes = newint[0]; >/@wht4- j
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privateint startIndex = 0; J?]wA1
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public PaginationSupport(List items, int 3K2B7loD)~
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totalCount){ tk'1o\@p9b
setPageSize(PAGESIZE); rucgav
setTotalCount(totalCount); @ev"{dY
setItems(items); I$.HG]
setStartIndex(0); w$Zi'+&*
} 0w M2v[^YO
c2Q KI~\x
public PaginationSupport(List items, int q~esxp
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totalCount, int startIndex){ 6#[
setPageSize(PAGESIZE); ]S@zhQ
setTotalCount(totalCount); RLy(Wz3%
setItems(items); V
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setStartIndex(startIndex); `1}WQS
} aQjs5RbP~
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public PaginationSupport(List items, int 6_Ps*Ed
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totalCount, int pageSize, int startIndex){ +rAmy
setPageSize(pageSize); E@}N}SR
setTotalCount(totalCount); hkS0 ae
setItems(items); bTBV:]w
setStartIndex(startIndex); H7{)"P]{f
} c`S`.WID
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publicList getItems(){ WP*xu-(:
return items; " pg5w
} ~e|RVY,
9:DT+^BB
publicvoid setItems(List items){ 3K;V3pJ].
this.items = items; Db:^Omwo
} kq| r6uE
JWZG)I]r
publicint getPageSize(){ =VC"X ?N
return pageSize; V{jQ=<)@e
} JRti2Mu
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publicvoid setPageSize(int pageSize){ z):LF<
this.pageSize = pageSize; e}f#dR+(
} voX4A
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publicint getTotalCount(){ `O+}$wP
return totalCount; Dq07Z^#'
} F,dPmR
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publicvoid setTotalCount(int totalCount){ {lam],#r
if(totalCount > 0){ {ef9ov Xk
this.totalCount = totalCount; >m:;.vVY
int count = totalCount / Nxm^jPM0
xDqJsp=]-
pageSize; u[:-^H
if(totalCount % pageSize > 0) `T'[H/
count++; t=l@(%O 0_
indexes = newint[count]; U/}("i![Dy
for(int i = 0; i < count; i++){ V ,+&.A23
indexes = pageSize * ttP|}|O
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i; hs;YMUA"
} :)9CG!2y<M
}else{ WswM5RN
this.totalCount = 0; _cc37[
} 8SZZ_tS3r
} hkpS}*L9o
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publicint[] getIndexes(){ MnLo{G]
return indexes; fA$2jbGW
} ltWEA
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publicvoid setIndexes(int[] indexes){ b6%[?k
this.indexes = indexes; $.Ia;YBf
} C.|.0^5
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publicint getStartIndex(){ ,kQCCn]
return startIndex; 2y"L&3W
} m~I@q
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publicvoid setStartIndex(int startIndex){ /wi*OZ7R
if(totalCount <= 0) !We9T )e
this.startIndex = 0; *w#^`yeo
elseif(startIndex >= totalCount) QbJE+m5
this.startIndex = indexes }j)][{i*x
zQxTPd
[indexes.length - 1]; R@df~
elseif(startIndex < 0) uv|RpIv e:
this.startIndex = 0; 8l>7=~Egp
else{ q _INGCJ
this.startIndex = indexes ' Ig:-
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[startIndex / pageSize]; 9oj#5Hq
} 9GX'+$R]
} oA* 88c+{f
A(D>Zh6 o@
publicint getNextIndex(){ u?4d<%5R!
int nextIndex = getStartIndex() + f8?hEa:js
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pageSize; iBPIj;,
if(nextIndex >= totalCount) H2S/!Q;K
return getStartIndex(); $jg~a
else ]>/oo =E
return nextIndex; H73 r3BH
} Pk3b#$+E
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publicint getPreviousIndex(){ 79z/(T+
int previousIndex = getStartIndex() - t`-
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pageSize; LVaJyI@/>
if(previousIndex < 0) v8"Zru
return0; m0i,Zw{eM
else N0pA ,&
return previousIndex; :bq${
} *L&|4|BF2
r,<p#4(>_
} W5uC5C*,l
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抽象业务类 v=_Ds<6n
java代码: en"\2+{Cg
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/** V
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* Created on 2005-7-12 jA? 7>"|
*/ vX?C9Fr 2
package com.javaeye.common.business; d"=)=hm!
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import java.io.Serializable; nGM;|6x"8|
import java.util.List; lMmP]{.>$
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import org.hibernate.Criteria; v]'\]U^
import org.hibernate.HibernateException; *&z!y/
import org.hibernate.Session; RGLJaEl !
import org.hibernate.criterion.DetachedCriteria; s$kvLy<
import org.hibernate.criterion.Projections; SN 4JX
import FMtg7+Q|>
sk5B} -
org.springframework.orm.hibernate3.HibernateCallback; zWrynJ}s
import G '%ZPh89
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org.springframework.orm.hibernate3.support.HibernateDaoS R].xT-1
@dn&M9Z
upport; BS2'BS8
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import com.javaeye.common.util.PaginationSupport; gSHN,8.
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public abstract class AbstractManager extends ',1[rWyc
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HibernateDaoSupport { ?^ R"a##
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privateboolean cacheQueries = false; Z kBWVZb
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privateString queryCacheRegion; R"{P#U,HNO
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publicvoid setCacheQueries(boolean YB_fy8Tfx
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cacheQueries){ *|^||
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this.cacheQueries = cacheQueries; RS|*3
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} `Bb32L
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publicvoid setQueryCacheRegion(String y:Ag mr,S
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queryCacheRegion){ ctPT=i60
this.queryCacheRegion = sw50lId
e35 ")z~
queryCacheRegion; %NcBq3
} 4WPco"xH!
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publicvoid save(finalObject entity){ P=a&>i
getHibernateTemplate().save(entity); wjTW{Bg~G
} [sK'jQo-[1
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publicvoid persist(finalObject entity){ iM$iZ;Tp
getHibernateTemplate().save(entity); {5 3#Xd
} vcZ"4%w
@W=:r/
publicvoid update(finalObject entity){ I5]58Ohx
getHibernateTemplate().update(entity); Qnx?5R-}ZU
} }+giQw4
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publicvoid delete(finalObject entity){ BnG{)\s
getHibernateTemplate().delete(entity); d>0 j!+s
} HP=5a.
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publicObject load(finalClass entity, )"g @"LJ=
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finalSerializable id){ (S_1C,
return getHibernateTemplate().load p::`1
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(entity, id); >ktekO:H
} 6ZQ$5PY
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publicObject get(finalClass entity, bRJ]avR
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finalSerializable id){ 6&btAwvOHx
return getHibernateTemplate().get >}r
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(entity, id); S-79uo
} @2eH;?uO
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publicList findAll(finalClass entity){ 6?-,@e
return getHibernateTemplate().find("from `a8 &7J(
?SX0e(+}}
" + entity.getName()); 1]aya(
} ,w,)n^
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publicList findByNamedQuery(finalString 6-\C?w
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namedQuery){ UdFYG^i
return getHibernateTemplate k~]\kv=
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().findByNamedQuery(namedQuery); [bEm D
} 0C717
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publicList findByNamedQuery(finalString query, MNX-D0`g
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finalObject parameter){ CWkAc5
return getHibernateTemplate 9abn6S(XpJ
h[]3#
().findByNamedQuery(query, parameter); uvA 2`%T/
} ^3nB2G.ax
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publicList findByNamedQuery(finalString query, mnH1-}oL
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finalObject[] parameters){ % %QAC4
return getHibernateTemplate Ws[d. El
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().findByNamedQuery(query, parameters); X'5+)dj
} u2 U4MV1C
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publicList find(finalString query){ `4"&_ltD
return getHibernateTemplate().find NmV][0(BS
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(query); ]2xoeNF/W{
} kN*\yH|
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publicList find(finalString query, finalObject cx4'rK.
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parameter){ q?oJ=]m"
return getHibernateTemplate().find 7
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(query, parameter); l5_%Q+E_
} ]GPUL>7
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public PaginationSupport findPageByCriteria wqp(E+&
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(final DetachedCriteria detachedCriteria){ +,}CuF
return findPageByCriteria 0'Qo eFKG
2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z(beT e
} 7033#@_
s}":lXkrw
public PaginationSupport findPageByCriteria mQt?d?6
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(final DetachedCriteria detachedCriteria, finalint .g6(07TyV
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startIndex){ :6Sb3w5h
return findPageByCriteria U_e e3KKA
p%*!]JRS
(detachedCriteria, PaginationSupport.PAGESIZE, |y7#D9m
%LZf=`:(
startIndex); ;?:X_C
} ?ik6kWI
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public PaginationSupport findPageByCriteria oNBYJ]t
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(final DetachedCriteria detachedCriteria, finalint ,h$j%->U
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pageSize, >a1ovKF
finalint startIndex){ g,cl|]/\d
return(PaginationSupport) h3:dO|Z
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getHibernateTemplate().execute(new HibernateCallback(){ 'D;'Pr]
publicObject doInHibernate dKTUW<C
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(Session session)throws HibernateException { ;/-#oW@gQ
Criteria criteria = {piZm12q?
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detachedCriteria.getExecutableCriteria(session); iG;GAw|E
int totalCount = We,~P\g
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((Integer) criteria.setProjection(Projections.rowCount ^aO\WKkA
r` (U3EgP
()).uniqueResult()).intValue(); 18U
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criteria.setProjection GPnSdGLC
FzGla} )
(null); ZN?UkFnE
List items = ;}gS8I|
dq
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criteria.setFirstResult(startIndex).setMaxResults FqK2[]8
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(pageSize).list(); L`{EXn[
PaginationSupport ps = &O.S ;b*+
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new PaginationSupport(items, totalCount, pageSize, o\YF_235
nANoy6z:
startIndex); I~>L4~g)
return ps; h47l;`kD-#
} A">A@`}
}, true); -!]dU`:(X
} oLp:Z=
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public List findAllByCriteria(final jVpk) ;vC
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DetachedCriteria detachedCriteria){ 3 _tO
return(List) getHibernateTemplate Kr]`.@/.S
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().execute(new HibernateCallback(){ 5:H9B
publicObject doInHibernate *xOrt)D=
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(Session session)throws HibernateException { T9+ ?A
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Criteria criteria = +}@HtjM
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detachedCriteria.getExecutableCriteria(session); cHMS[.=;
return criteria.list(); Y+tXWN"8
} Y@Kp'+t(!
}, true); m,U`hPJ
} z_p/.kQ'5
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2
public int getCountByCriteria(final }]H_|V*f
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DetachedCriteria detachedCriteria){ uFT&r|
Integer count = (Integer) AhARBgf<
qe:,%a-9
getHibernateTemplate().execute(new HibernateCallback(){ mSzBNvci
publicObject doInHibernate f9g#pyH4
$Q|t^(
(Session session)throws HibernateException { ?q<"!U|e
Criteria criteria = A8R}W=
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detachedCriteria.getExecutableCriteria(session); ?b~V uo
return [S/]Vk|4
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criteria.setProjection(Projections.rowCount *_z5Pa`A
6 /Apdn1[
()).uniqueResult(); rnVh
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} #U NTD4
}, true); TK;*:K8oe
return count.intValue(); T}X#I'Z
} +M6qbIO
} $Rsf`*0-
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用户在web层构造查询条件detachedCriteria,和可选的 u4=j!Zb8}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]iuM2]
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 $@t-Oor;
ps.getIndexes()得到分页索引的数组 31y=Ar""
ps.getTotalCount()得到总结果数 ubIGs|p2c
ps.getStartIndex()当前分页索引 Cd#>,,\z
ps.getNextIndex()下一页索引 1@kPl[`p'
ps.getPreviousIndex()上一页索引 jl=<Q.Mm7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $Tt@Xu
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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 AyKaazm]9
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一下代码重构了。 n< [np;\
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我把原本我的做法也提供出来供大家讨论吧: SU9#Y|I
Pn5@7~
首先,为了实现分页查询,我封装了一个Page类: lC+p2OG^[
java代码: o*\kg+8
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/*Created on 2005-4-14*/ c/I.`@
package org.flyware.util.page; S?%V o* Y
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/** k`r}Gb
* @author Joa :*e0Z2=
* 8f% @
*/ viAvD6e
publicclass Page { N7*JL2Rnq
]YZ+/:#U7
/** imply if the page has previous page */ _tL*sA>[~)
privateboolean hasPrePage; > >wbyj8
Va06(Cq
/** imply if the page has next page */ fM_aDSRa!H
privateboolean hasNextPage;
= Ow}MX
fEdQR->
/** the number of every page */ \0Zm3[
privateint everyPage; *L/_ v
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/** the total page number */ LGPy>,!
privateint totalPage; t(CdoE,6
Lm9y!>1"O
/** the number of current page */ 0X -u'=Bs
privateint currentPage; er^z:1'
fSl+;|Kn
/** the begin index of the records by the current >\8Bu#&s4
tuK"}HepB
query */ =R!=uml(
privateint beginIndex; +M
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Fm{Ri=X<:
<dDGV>n4;
/** The default constructor */ }
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public Page(){ =V_}z3b
$# @G!
} N-
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3`J?as@^8
/** construct the page by everyPage Xcicqywe?
* @param everyPage X_|8CD-@6
* */ P@p(Y2&~g
public Page(int everyPage){ 1#Dpj.cO#
this.everyPage = everyPage; _$0<]O$
} jwTb09
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/** The whole constructor */ PX[taDN
public Page(boolean hasPrePage, boolean hasNextPage, ^M
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int everyPage, int totalPage, rZe"*$e
int currentPage, int beginIndex){ IO`.]iG
this.hasPrePage = hasPrePage; ,y3o ,gl
this.hasNextPage = hasNextPage; 57)S"
this.everyPage = everyPage; s7SW4ff1
this.totalPage = totalPage; 4kNf4l9Y
this.currentPage = currentPage; BkJV{>?_+
this.beginIndex = beginIndex; w]UYD;f
} t'_Hp},
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/** +e%9P%[+
* @return Tm_AoZH
* Returns the beginIndex. ]o_Z3xXUa
*/ zVZZdG~8
publicint getBeginIndex(){ Jj|HeZ1C f
return beginIndex; Yp./3b VO
} n%3rv?m7
/P5w}n
/** a
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* @param beginIndex NUEy0pLw
* The beginIndex to set. OTL=(k
*/ {~k/xM.-
publicvoid setBeginIndex(int beginIndex){ ~LuZpV
this.beginIndex = beginIndex; N/TUcG|m\
} }qG{1Er
&'N{v@Oi)
/** d%81}4f:
* @return c7q1;X{:
* Returns the currentPage. %(Nu"3|$K=
*/ ._~_OVU
publicint getCurrentPage(){ (X,Ua+{
return currentPage; za1MSR
} vO%n~l=
p8oOm>B96n
/** x$J1%K*
* @param currentPage 2+TCFpv
* The currentPage to set. *.ri8
*/ X7?p$!M6;B
publicvoid setCurrentPage(int currentPage){ 9loWh5_1Z
this.currentPage = currentPage; |zKe*H/
} 4Ucg<Z&%
\ZigG{
/** S WVeUL#5
* @return =2\k
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* Returns the everyPage. nY'0*:'u
*/ 1<fS&)^W
publicint getEveryPage(){ rC14X} X6
return everyPage; \$/)o1SG
} x:88E78
7;#9\a:R?
/** 4cRF3$amd
* @param everyPage $}jp=?,t
* The everyPage to set. 7$<.I#x
*/ wXMKQ)$(
publicvoid setEveryPage(int everyPage){ KF|+#qCN
this.everyPage = everyPage; n&D<l '4
} Z%y>q|:
!Sy._NE`z
/** _Buwz_[&
* @return \acJ9N
* Returns the hasNextPage. U,LW(wueT
*/ j5|_SQOmt
publicboolean getHasNextPage(){ LU l6^JU
return hasNextPage; |o6
h:g
} XpdDIKMmE
#25Z,UU
/** 6B)(kPW
* @param hasNextPage =\B{)z7@6D
* The hasNextPage to set. 9
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*/ sNc(aGvy
publicvoid setHasNextPage(boolean hasNextPage){ 9AD`,]b
this.hasNextPage = hasNextPage; C~ t?<
} am{f<v,EI
oN)l/"%C7/
/** =SB#rCH
* @return h8Q+fHDYv
* Returns the hasPrePage. X]U,`oE)9
*/ Q g"hN
publicboolean getHasPrePage(){ hF s:9
return hasPrePage; 01g=Cg
} >N@tInE
K}tl,MMU
/** /1F%w8Iqh
* @param hasPrePage %I9{)'+@x
* The hasPrePage to set. X|q&0W=
*/ rIH/<@+
publicvoid setHasPrePage(boolean hasPrePage){ 'C8VD+p
this.hasPrePage = hasPrePage; "=@b>d6U+
} n .ZLR=P4
8i!AJF9IQ}
/** nBI?~hkP3
* @return Returns the totalPage. u =z$**M^
* = I,O+^
*/ VLC<ju!
publicint getTotalPage(){ B]L5K~d
return totalPage; U&yXs'3a&
} .+MJ' bW
H;s
/** XE*
@*
* @param totalPage 'iA#lKG
* The totalPage to set. 4sasf94
*/ SeN4gr*
publicvoid setTotalPage(int totalPage){ $,v
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this.totalPage = totalPage; Zk4Hs%n
} GR@!mf
+~?ze,Di
} X,n4_=f
&lbxmUeU
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id<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 SNV~;@(h
)Fx"S.Ok
个PageUtil,负责对Page对象进行构造: 11[[H kX@
java代码: reR ><p
C,~wmS )@
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/*Created on 2005-4-14*/ \ZX5dFu0
package org.flyware.util.page; h[#Lg3
i]J*lM7'
import org.apache.commons.logging.Log; g}"`@H(9r3
import org.apache.commons.logging.LogFactory; xI}o8G KQq
k"D6Vyy`
/** XTEC0s"F
* @author Joa I=o[\?u*_
* to,DN2rN
*/ ("Z;)s4q
publicclass PageUtil { s0uI;WMg
;*1bTdB5a
privatestaticfinal Log logger = LogFactory.getLog x=T`i-M
ma9q?H#X
(PageUtil.class); [ -"o5!0<
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/** K]ob>wPf
* Use the origin page to create a new page nwswy]e8/
* @param page +^ a9i5
* @param totalRecords bP\0S@1YL
* @return A'r 3%mC
*/ QA>(}u\+
publicstatic Page createPage(Page page, int qzS 9ls>>
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totalRecords){ rCfr&>nn
return createPage(page.getEveryPage(), <6QG7i
uMVM- (g%
page.getCurrentPage(), totalRecords); s3qWTdM
} nfpkWyI u{
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/** mAMi-9
* the basic page utils not including exception **_`AM~
JLUG=x(dA
handler Py7!_TX
* @param everyPage t\~lGG-p
* @param currentPage i)9}+M5
* @param totalRecords ;, P-2\V/
* @return page arJ4^ d
*/ &7z79#1NS
publicstatic Page createPage(int everyPage, int U<,@u,_Ja
2gz}]_
currentPage, int totalRecords){ kms&o=^
everyPage = getEveryPage(everyPage); D^Ahw"X)
currentPage = getCurrentPage(currentPage); W%LTcm
int beginIndex = getBeginIndex(everyPage, ?&;d#z*4
KilgeN:
currentPage); CvfXm
int totalPage = getTotalPage(everyPage, >2h|$6iWP
X8~dFjhX
totalRecords); *uHL'Pe;m
boolean hasNextPage = hasNextPage(currentPage, uo0g51%9
=OfU#i"c
totalPage); -YM#.lQ
boolean hasPrePage = hasPrePage(currentPage);
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n,sf$9"
returnnew Page(hasPrePage, hasNextPage, /~3~Xc~=p
everyPage, totalPage, (Mi]vK.4
currentPage, Y.`
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Y<|!)JLB2
beginIndex); S\fEV"
} )006\W|t9
1Vq]4_09g1
privatestaticint getEveryPage(int everyPage){ lOIBX@K E
return everyPage == 0 ? 10 : everyPage; mr:;Wwd
} Yhdt"@;..
X-1<YG
privatestaticint getCurrentPage(int currentPage){ ",/3PT
return currentPage == 0 ? 1 : currentPage; O@JgVdgf
} m|q?gX9R
[Du@go1C
privatestaticint getBeginIndex(int everyPage, int dFY]~_P472
3TUW+#[Gu
currentPage){ ]jbQou@
return(currentPage - 1) * everyPage; GMmz`O
XN
} g8^\|
E)==!T@E
privatestaticint getTotalPage(int everyPage, int n]M1'yU
\b{Aj,6,
totalRecords){ 6k6M&a
int totalPage = 0; / hUuQDJ
5G .Fi21
b
if(totalRecords % everyPage == 0) Bz}Dgbb
totalPage = totalRecords / everyPage; fw>@:m_bK
else !iKR~&UpAL
totalPage = totalRecords / everyPage + 1 ; u] C/RDTH
l;i,V;@t
return totalPage; !0ly1T 9
} Y.I-hl1<r
zJ{?'kp
privatestaticboolean hasPrePage(int currentPage){ G| 7\[!R
return currentPage == 1 ? false : true; a<X8l^Ln
} blxAy
.G[y^w)w}
privatestaticboolean hasNextPage(int currentPage, o(xRq;i
#_yQv? J
int totalPage){ rfqw/o
return currentPage == totalPage || totalPage == xdWfrm$;ZA
^NJ]~h{n$
0 ? false : true; Zgp]s+%E
} [6x-c;H_4
0_yE74i
F#=XJYG1
} t~pA2?9@
{MmHR
`@GqD
`|K,E
b?Wg|D
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。 3L/qU^`
=ark?<E
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 %M8Egr2|0
a%*l]S0z"
做法如下: ~ILig}I
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;9r
Z{'i+|
`-zdjc d
的信息,和一个结果集List: *]2LN$
java代码: $>E\3npV
"bZV<;y6
/UeLf$%ZW
/*Created on 2005-6-13*/ `x:znp} '
package com.adt.bo; Oq"(oNG@
j0J}d _
import java.util.List; ~82[pY
o?\)!_Z|
import org.flyware.util.page.Page; Ore$yI}!m
UnNvlkjq9
/** )#-27Y
* @author Joa 4GJ1P2
*/ 'B}pIx6k~
publicclass Result { tf64<j6
D|I(2%aC
private Page page; kTQ:k
}%B
A7U'>r_.
private List content; CG'NC\x5
M9Gs^
/** .4={K)kz|F
* The default constructor *D`qcv
*/ 'G6TSl
public Result(){ [+$l/dag
super(); Z :f0>
} Z&8
7Aj
U
-~%-gFC
/** GypZ!)1
* The constructor using fields 8xhXS1
* GZT}aMMSJ
* @param page \C.%S +u
* @param content 1A^iUC5)
*/ i}
96,{
public Result(Page page, List content){ P8NKpO\
this.page = page; >JT{~SRB|Y
this.content = content; BmYU#h
} 8)/i\=N3;
GkMNV7"m
/**
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* @return Returns the content. |Y3!Lix
*/ hZnT`!iFE^
publicList getContent(){ -Nmf}`_
return content; 992;~lBu
} }yqRz6=YB
`7jm
/** Fk D
* @return Returns the page. mOwgk7s[J
*/ :NU-C!eT
public Page getPage(){ s#w+^Mw$
return page; Qo
} rh2pVDS
IWu^a w
/** i]GBu
* @param content !s,<hU#
* The content to set. c5P52_@
*/ c?)
pn9
public void setContent(List content){ Wq)'0U;{$
this.content = content; A{h
hnrr8
} , >Y.!
_yjM_ALjo
/** $m/-E#I#Z
* @param page U[d/`
* The page to set. FcIH<_r
*/ $}oQ=+c5
publicvoid setPage(Page page){ e<5+&Cj
this.page = page; N&NOh|YS
} V2es.I
} zcJ]US
G_5sF|(mq
OxElvbM#
vVyO}Q`
q" wi.&|
2. 编写业务逻辑接口,并实现它(UserManager, !|_
CXm
T|
MIa].S#
UserManagerImpl) <0P`ct0,i
java代码: WAY<X:|We
&ukNzV}VW
GQqw(2Ub}
/*Created on 2005-7-15*/ !N$4.slr<p
package com.adt.service; =D5@PHpv(
7qE V5!
import net.sf.hibernate.HibernateException; qNHS 1
w GZ(bKyO
import org.flyware.util.page.Page; *"
<tFQ
{N5g52MN
import com.adt.bo.Result; 7~\Dzcfk"P
NOyLZa'
/** QXJD'c
* @author Joa $Fz/&;KX!
*/ ([|5(Omd\
publicinterface UserManager { +^YV>;
_if&a'
public Result listUser(Page page)throws ?y<n^`
XeDU
,
HibernateException; I#eIm3Y?
R,Zuy(g
} hD<z^j+
?d+B]VYw
;YZw{|gsh
};o R x)
zQ{ Q>"-
java代码: ("/*k
$O}gl Q
IX7d[nm39
/*Created on 2005-7-15*/ Ccz:NpK+
package com.adt.service.impl; qjR;c&
q R
8e>;E
import java.util.List; ^%_B'X9
8YkP57Y%[Z
import net.sf.hibernate.HibernateException; BCUw"R#
RB/[(4
import org.flyware.util.page.Page;
(i *1M
import org.flyware.util.page.PageUtil; ?[!.TU?4N
)2S0OY.
import com.adt.bo.Result; ""pJO 6bI
import com.adt.dao.UserDAO; $L</{bXW
import com.adt.exception.ObjectNotFoundException; {(a@3m~a%
import com.adt.service.UserManager; 3kR- WgVF,
^ Jnp\o>
/** R2]?9\II
* @author Joa 3 tXtt@Yy
*/ 9}}D -&Mc
publicclass UserManagerImpl implements UserManager { )Xd=EWGUS
GsDSJz
private UserDAO userDAO; QQ2xNNF[
^|\ *i
/** KD,b.s
* @param userDAO The userDAO to set. :@:R4Ac
*/ =m} {g/Bk
publicvoid setUserDAO(UserDAO userDAO){ AL|fL
this.userDAO = userDAO; Fg#*rzA
} }GkEv}~t
nWXI*%m5
/* (non-Javadoc) :Hd?0eZ|
* @see com.adt.service.UserManager#listUser CWBsiL
f
,}{E+e5jh7
(org.flyware.util.page.Page) =Rb, `%
*/ -^#Ix;%
public Result listUser(Page page)throws )_j.0a
>5^Z'!Z"
HibernateException, ObjectNotFoundException { [*}[W6
3v
int totalRecords = userDAO.getUserCount(); ;/oMH/,U8
if(totalRecords == 0) 4D58cR}
throw new ObjectNotFoundException ~-M7
Ch;EnN<
("userNotExist"); *[.\S3K`
page = PageUtil.createPage(page, totalRecords); 6Ir
?@O1'!
List users = userDAO.getUserByPage(page); T$}<So|
returnnew Result(page, users); 42m`7uQ
} 8 6L&u:o:
h)y"?Jj
} _^a.kF
m@zxjIwT
^S<Z'S
8kMMQ ES
y|MW-|0=!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 t4gD*j6J3
sp_(j!]jX
询,接下来编写UserDAO的代码: XLmbpEh
3. UserDAO 和 UserDAOImpl: %{}Jr`
java代码: 3tr?-l[N\
$ng\qJ"HF
];uvE? 55
/*Created on 2005-7-15*/ U Ciq'^,
package com.adt.dao; 1]hMA\x
)3..7ht3^5
import java.util.List; <CA
lJ
PKjA@+
import org.flyware.util.page.Page; E0)v;yRcw
ie$=3nZJ}
import net.sf.hibernate.HibernateException; ~!:F'}bj
m2_&rjGz
/** (b{
{B$O
* @author Joa {.!:T+'Xi\
*/ mDM]RAub)
publicinterface UserDAO extends BaseDAO { " jeJV,%
-Q$$2QW!
publicList getUserByName(String name)throws 5n9F\T5
"%.#/!RG
HibernateException; 3}h&/KN{
a#raUF7e
publicint getUserCount()throws HibernateException; 8AefgjE
p O:
EJ
publicList getUserByPage(Page page)throws x &9I2"
<c\aZ9+V
HibernateException; B]Zsn`n
,#c-"xY
} ^
1J;SO|
n:#ji|wM
Xp{gh@#dr
y!v $5wi
@{nT4{
java代码: Vm6^'1CY
u*9C(je
MiSFT5$v6
/*Created on 2005-7-15*/ Ab(bvS8r$
package com.adt.dao.impl; Cog:6Gnw
c3
wu&*p{
import java.util.List; +m+HC(Z
W:) M}}&H
import org.flyware.util.page.Page; [{ zekF~)@
+6;OB@
import net.sf.hibernate.HibernateException; -_4! id
import net.sf.hibernate.Query; aoJ&< vl3
{;-$;\D
import com.adt.dao.UserDAO; RMvlA'c
yGD0}\!n
/** \4vFEJSh
* @author Joa /S;?M\
*/ }Ns_RS$
public class UserDAOImpl extends BaseDAOHibernateImpl db4&?55Q
P0z "Eq0S
implements UserDAO { bu hxC5i%
yqBu7E$X
/* (non-Javadoc) Iy,)>V%iZV
* @see com.adt.dao.UserDAO#getUserByName D^TKv;%d
_n_i*p
'2
(java.lang.String) QWxQD'L'
*/ N\Hd3Om
publicList getUserByName(String name)throws 8bK}&*z<
[]Fy[G.)H
HibernateException { H~$|y9>qI
String querySentence = "FROM user in class ~]yqJYiid^
-[7.VP
com.adt.po.User WHERE user.name=:name"; p5[uVRZ
Query query = getSession().createQuery Kp&d9e{
Yc
?_^9e
(querySentence); X<?;-HrS;
query.setParameter("name", name); 5$#<z1M.&
return query.list(); ZHF@k'vm/9
} DMf9wB
P;y/`_jo
/* (non-Javadoc) A%2!Hr
* @see com.adt.dao.UserDAO#getUserCount() jG^~{7#
*/ zeua`jQ
publicint getUserCount()throws HibernateException { 3n/L;T,X
int count = 0; Jg Xbs+.
String querySentence = "SELECT count(*) FROM '+eP%Y[W%
h]=chz
user in class com.adt.po.User"; )l"0:1I g
Query query = getSession().createQuery S4(IYnwN
V*TG%V -
(querySentence); b,@:eVQ7
count = ((Integer)query.iterate().next .DX#:?@4@Y
[Dt\E4
()).intValue(); awawq9)Y
return count; O@$hG8:
} ^Uf`w7"iY
O7K))w
/* (non-Javadoc)
h!Q>h7
* @see com.adt.dao.UserDAO#getUserByPage _AO0:&
'v,W
gPe
(org.flyware.util.page.Page) =DCQ!02
*/ ydFY<Mb(o
publicList getUserByPage(Page page)throws >:xnjEsi$/
>2|#b
HibernateException { K
l4",
String querySentence = "FROM user in class "s*{0'jo
kQb0pfYs
com.adt.po.User"; QxkfP %_g
Query query = getSession().createQuery jsG9{/Ov3
[:k'VXL
(querySentence); _m&VdIPO
query.setFirstResult(page.getBeginIndex()) ,S8Vfb &
.setMaxResults(page.getEveryPage()); 1dq.UW\
return query.list(); Rsulp#['
} p<+]+,|\~:
f*I5m=
} tyDtwV|
)CmuC@ Q"
K1hw'AaQ
OYzJE@r^
_+. t7q^
至此,一个完整的分页程序完成。前台的只需要调用 QZfPd\Q5
mA."*)8VNg
userManager.listUser(page)即可得到一个Page对象和结果集对象 .SsIU\[)
f^]AyU;F:
的综合体,而传入的参数page对象则可以由前台传入,如果用 kj8zWG4KH
`SG70/
webwork,甚至可以直接在配置文件中指定。 u1"e+4f
9@j~1G%^
下面给出一个webwork调用示例: i" )_M|
java代码: l?~ci
;lG
mSzwx/3"
p"JSYF
9]
/*Created on 2005-6-17*/ EW!$D
package com.adt.action.user; AVJk
dnx}c4P
import java.util.List; GGBe/X
zPmVECS
import org.apache.commons.logging.Log; d!d
3r W;A
import org.apache.commons.logging.LogFactory; 4 hj2rK'y
import org.flyware.util.page.Page; VgdkCdWRm_
]`NbNr]K
import com.adt.bo.Result; *Z]|
Z4Q/`
import com.adt.service.UserService; NqWHR~&
import com.opensymphony.xwork.Action; Z:*U/_G
7Y)wu$!7}
/** ,VZ&Gc
* @author Joa daorKW4
*/ =.%ZF]Oe+#
publicclass ListUser implementsAction{ q!,do2T
D;L :a`Y
privatestaticfinal Log logger = LogFactory.getLog TM}F9!*je
3 x'30
(ListUser.class); ky#6M?
\
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private UserService userService; KZE.}8^%D
2eK\$_b_
private Page page; e!8_3BE
{$t*Mb0
privateList users; BuYDw*.
=6dKC_Q
/* g IKm
* (non-Javadoc) Gh
pd
k;
* A)#sh)
}Q
* @see com.opensymphony.xwork.Action#execute() 2mO#vTX4
*/ c>R(Fs|6
publicString execute()throwsException{ (w-u"1&
Result result = userService.listUser(page); VB#31T#q?
page = result.getPage(); g5Vr2
users = result.getContent(); @Otc$hj
return SUCCESS; KCu6:)6'
} oL@ou{iQ
-7$'* V9$
/** ]~zJ7I
* @return Returns the page. h=tu+pn
*/ Fs|;>Up0
public Page getPage(){ YUb,5Y0
return page; {|gJC>f@
} 9H}&Ri%
P~<93
/** acZHb[w
* @return Returns the users. `|w#K28t"
*/ D5>~'N3b
publicList getUsers(){ (0Qq rNs
return users; !VHIl&Mos
} t/ 1NTa
WK}+f4tdW[
/** =QfKDA
* @param page GN9_ZlC
* The page to set. 9/M!S[N9
*/ ?>8zU;Aj
publicvoid setPage(Page page){ qtN29[x
this.page = page; Ltw7b
} <`3(i\-X
G7;}309s
/** b1u'ukDP\
* @param users E?mp6R]}%
* The users to set. Q75^7Ga_
*/ ?<?C*W_
publicvoid setUsers(List users){ KUut C
:
this.users = users; +I n"OR%
} c.Y8CD.tqL
;8T=uCi
/** P`
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* @param userService ;QQ7vo
* The userService to set. "V0:Lq
*/ 7 !.8#A':
publicvoid setUserService(UserService userService){ "T
u[n\8
this.userService = userService; $0SZlq>En
} &] 6T^.
} --YUiNhh
/A.i5=k
/&:9VMMj
UMwMXmZNJ
~ p.W*skD
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, k#5e:VOb
)hW {>Y3x
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 }.) 43(>]
%QgAilj,
么只需要: 2P_^@g
java代码: ^(JHRH~=h
.GN$H>')
"EYjY->
<?xml version="1.0"?> Mgs|*u-5
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork V8$bPVps
B9Q.s
1.0//EN" "http://www.opensymphony.com/xwork/xwork- t/WnDR/fM
W+
'}O<
1.0.dtd"> 7B\(r~f`t
U<Y'.!
<xwork> W7=_u+0d
(OcNC/9
<package name="user" extends="webwork- )v{41sM+
.0E4c8R\X
interceptors"> by]|O
)UZ0gfx
<!-- The default interceptor stack name x5z4Yv^
m
OG+r|.N;
--> ,(27p6!
<default-interceptor-ref ~!-8l&C
\e8*vos
name="myDefaultWebStack"/> s]vJUC,s
Sje0:;;|
<action name="listUser" HL}~W}!j
Y0yO`W4
class="com.adt.action.user.ListUser"> \seG2vw$
<param pb6^sA%l
`vxrC&,As
name="page.everyPage">10</param> XH:gQ 9FD
<result ObyuhAR
N3yB1_
name="success">/user/user_list.jsp</result> 1|WpKaMoq
</action> t-m9n*\j1
&<V_[Wh"
</package> T[XP\!z]B!
\_Kt6=
</xwork> 9X$#x90
uWB:"&!^
27],O@2?L
/1W7<']>xV
n*i'v tQ8
Dyk[ug5
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 "-QRkif
>6[ X }
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 zRy5,,i5=[
myWmU0z/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 {pe7]P?
HCx%_9xlm
4-+ozC{
,M@m4bx
nK h%E-c
我写的一个用于分页的类,用了泛型了,hoho <duBwkiG
/iTUex7T
java代码: s"=F^#
B221}t
[CDX CV-z
package com.intokr.util; hX8gV~E=y
g{v5mly
import java.util.List; `
-[Bo
C^,4`OI
/** "37@Zt
* 用于分页的类<br> 6A$_&?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2z.8rNwT
* " _:iK]
* @version 0.01 +%
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* @author cheng ,_Qe}qFU
*/ XewXTd#x
public class Paginator<E> { xxoHH#a
privateint count = 0; // 总记录数 f
OM^V{)T
privateint p = 1; // 页编号 2E3?0DL",
privateint num = 20; // 每页的记录数 q:
TT4MUj<
privateList<E> results = null; // 结果 b=K6IX;
$m:2&lU3
/** &Mhv XHI
* 结果总数 [+%d3+27
*/ {1Ju}=69
publicint getCount(){ 2q-:p8
return count; bB;~,W&E1
} Q 7uAf3
*>aZc::
publicvoid setCount(int count){ U0h)pdo
this.count = count; T2:oWjC3$
} `;5VH ]V
"%oH@
=
/** >@)*Sn9"
* 本结果所在的页码,从1开始 HJfQ]p'nK2
* QiTR-M2C!
* @return Returns the pageNo. abROFI5.L
*/ U]V3DDN
publicint getP(){ @V* ju
return p; 8h&oSOkQk,
} C#U<k0R
z^gQ\\,4
/** `1fJ:b/M
* if(p<=0) p=1 {PODisl>\D
* #Mj$o;SX
* @param p |rE!
*/ n|70x5Z?}J
publicvoid setP(int p){ Q7~'![(a
if(p <= 0) @<D'-mMt
p = 1; V[o7Jr~
this.p = p; UAsF0&]
} SON^CvMs{
[&h#iTRT
/** Io$w|~x
* 每页记录数量 ZnvEv;P
*/ V!T^wh;
publicint getNum(){ '}jf#C1$c
return num; BIxV|\k
} _M8G3QOx
:3KO6/+
/** (3
IZ
* if(num<1) num=1 8hTR*e!+
*/ fL ~1
publicvoid setNum(int num){ ?,ZELpg n
if(num < 1) = EQN-{#
num = 1; w^06z,
this.num = num; H$z>OS_6U
} &Ki>h
j 0g5<M
/** Nk96"P$P
* 获得总页数 $|4cJ#;^L
*/ !oZQ2z~
publicint getPageNum(){ %04:z77
return(count - 1) / num + 1; i{o#3
} [Ja)<!]<
_1I K$gb[
/** @%6)^]m}r
* 获得本页的开始编号,为 (p-1)*num+1 cC^W2\
*/ 9@:BK;Fi
publicint getStart(){ QCeMKjCmY
return(p - 1) * num + 1; JB&G~7Q85
} y,MPGW_
<RhOjZgyZ
/** F(#ha J$>
* @return Returns the results. EkN_8(w
*/ z%OuI 8"'
publicList<E> getResults(){ R=!kbBK>\
return results; Q;4}gUmI$
} L +L9Y}
;tJWOm
public void setResults(List<E> results){ :]vA2
this.results = results; iV5}U2Vh
} sW
}<zGYd
5\okU"{d7
public String toString(){ V?OuIg%=:
StringBuilder buff = new StringBuilder :1:3Svb<Y
8]S,u:E:N
(); 3^{8_^I
buff.append("{"); }1 $h xfb
buff.append("count:").append(count); + c`AE
buff.append(",p:").append(p); M2}np
buff.append(",nump:").append(num); Vwjk[ DOL
buff.append(",results:").append ov8
ByJc
?Phk~ jE
(results); kW#S]fsfU
buff.append("}"); q[-|ZA bbr
return buff.toString(); ]JH64~a
} 9/#0?(K8
1o8wy_eSs
} 0s1'pA'
G3G/xC"
$30oc
Tt{