Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 29DYL
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 hqW4.|&\c
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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 8<UD#i@:C
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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 T8&
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分页支持类: vT)(#0>z
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java代码: 7iCH$}
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package com.javaeye.common.util; t\J5np
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import java.util.List; q:4 51 C
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publicclass PaginationSupport { BsV2Q`(gT
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publicfinalstaticint PAGESIZE = 30; ^vXMX^*
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privateint pageSize = PAGESIZE; Xx_v>Jn!
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privateList items; N|[P%WM3
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privateint totalCount; 4G`7]<
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privateint[] indexes = newint[0]; gBQK
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privateint startIndex = 0; GxWA=Xp^~G
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public PaginationSupport(List items, int FB{4& ;
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totalCount){ r`5[6)+P
setPageSize(PAGESIZE); +L_!$"I
setTotalCount(totalCount); %?K1X^52d
setItems(items); gqR?hZD
setStartIndex(0); M>hHTa?W
} ,7:_M>-3g
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public PaginationSupport(List items, int PjriAlxD
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totalCount, int startIndex){ @vWf-\
setPageSize(PAGESIZE); nQ4 s
setTotalCount(totalCount); @!z9.o;
setItems(items); VT1Nd
setStartIndex(startIndex); J(+I`
} <fq?{z
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public PaginationSupport(List items, int E)liuu!qI
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totalCount, int pageSize, int startIndex){ OZ\ ]6]L
setPageSize(pageSize); Ei!5Qya>
setTotalCount(totalCount); dn0?#=
setItems(items); ]m}<0-0
setStartIndex(startIndex); jj^{^,z\
} >vE1,JD)w
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publicList getItems(){ pp{Za@j
return items; jQjtO"\JG
} rb_ cm
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publicvoid setItems(List items){ e%#(:L
this.items = items; 6x%uWZa'
} m1DzUq;
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publicint getPageSize(){ vJ96qX
return pageSize; |0 #J=am
} pE{ZWW[@+
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publicvoid setPageSize(int pageSize){ L~N<<8?\
this.pageSize = pageSize; ]O
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} L}O_1+b
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publicint getTotalCount(){ 2\h]*x%:
return totalCount; ~nk{\ rWO
} .>z)6S_G
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publicvoid setTotalCount(int totalCount){ nbM[?=WS
if(totalCount > 0){ ]k~k6#),;
this.totalCount = totalCount; GtcY){7
int count = totalCount / VfAC&3%M
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pageSize; @QiuCB
if(totalCount % pageSize > 0) ()1\b
count++; Y<%)Im6v/
indexes = newint[count]; ;ru=z@
for(int i = 0; i < count; i++){ f\+MnZ4[Qj
indexes = pageSize * >r+Dl\R
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i; g{K*EL<
} ceN*wkGyB
}else{ emp*j@9
this.totalCount = 0; a4HUP*
} H^ _[IkuA%
} 4QbD DvRQ^
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publicint[] getIndexes(){ ?f!w:zp
return indexes; 4B>N[#-0=
} 8>" vAEf
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publicvoid setIndexes(int[] indexes){ 3|4jS"t{f
this.indexes = indexes; ta`}}I
} *Dx&} "
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publicint getStartIndex(){ f0rM 4"1
return startIndex; ^_FB .y%
} ^|yw)N]Q/
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publicvoid setStartIndex(int startIndex){ -*8 |J;
if(totalCount <= 0) }Z5f5q
this.startIndex = 0; k<p$BZ
elseif(startIndex >= totalCount) 4/Ub%t-
this.startIndex = indexes -a:+ h\K
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[indexes.length - 1]; EA.4m3
elseif(startIndex < 0) LE^kN<qMK
this.startIndex = 0; W]E6<y'
else{ ,B|~V 3)(
this.startIndex = indexes 7x8/Vz@\
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[startIndex / pageSize]; |F)BKo D
}
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} E^kB|; Ki
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publicint getNextIndex(){ ,PH ;j_
int nextIndex = getStartIndex() + OwXw9
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pageSize; ? <b>2j
if(nextIndex >= totalCount) l-` M
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return getStartIndex(); y[M<x5
else 13
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return nextIndex; AlP}H~|M7
} sPMCN's
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publicint getPreviousIndex(){ M*M,Z
int previousIndex = getStartIndex() - ykFm$ 0m+I
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pageSize; )kLTyx2&
if(previousIndex < 0) W Z'UVUi8
return0; \\Ps*HN
else #R2wt7vE
return previousIndex; iTTUyftHT
} lu~<pfg
, y%!s27
} wrw4Uxq
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抽象业务类 J~.8.]gXW
java代码: DIrQ5C
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/** TmI~P+5w
* Created on 2005-7-12 FbH
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*/ VK>ZH^-
package com.javaeye.common.business; 8YroEX[5l
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import java.io.Serializable; v|DgRPY
import java.util.List; XMt)\r.
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import org.hibernate.Criteria; ?K5S{qG'O
import org.hibernate.HibernateException; v6uXik
import org.hibernate.Session; sa8Q1i&%
import org.hibernate.criterion.DetachedCriteria; .%~m|t+Rt
import org.hibernate.criterion.Projections; [ PXv8K%]p
import Uwj|To&QR
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org.springframework.orm.hibernate3.HibernateCallback; PfF5@W;E;
import !2YvG%t^6
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org.springframework.orm.hibernate3.support.HibernateDaoS -^C^3pms
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upport; -zn$h$N4
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import com.javaeye.common.util.PaginationSupport; lVb{bO9-O
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public abstract class AbstractManager extends CKB~&>xx
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HibernateDaoSupport { -jXO9Q
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privateboolean cacheQueries = false; ks3ydHe`
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privateString queryCacheRegion; H3Ws$vl9n
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publicvoid setCacheQueries(boolean \0)v5u
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cacheQueries){ x-E@[=
this.cacheQueries = cacheQueries; 4$~A%JN3
} m$XMq
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publicvoid setQueryCacheRegion(String Hl"^E*9x
)4O>V?B
queryCacheRegion){ W}6OMAbsE;
this.queryCacheRegion = (^!$m7
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queryCacheRegion; Ms>CO7Nvy
} TzSEQS{
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publicvoid save(finalObject entity){ q8m[ S4Q]g
getHibernateTemplate().save(entity); ]Lb Fh5;s
} zG^|W8um_
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publicvoid persist(finalObject entity){ J?R\qEq%
getHibernateTemplate().save(entity); lf`" (:./
} obzdH:S
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publicvoid update(finalObject entity){ wZe>}1t
getHibernateTemplate().update(entity); K;L6<a A#
} !c2<-3e
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publicvoid delete(finalObject entity){ Rz03he
getHibernateTemplate().delete(entity); Y|X!da/
} (&o|}"kRq
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publicObject load(finalClass entity, h/s8".\
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finalSerializable id){ 0bz':M#k &
return getHibernateTemplate().load >~}}*yp
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(entity, id); TxA%{0
} ;{j@ia
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publicObject get(finalClass entity, ->9waXRDz)
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finalSerializable id){ ;owU]Xk%8K
return getHibernateTemplate().get TdKo"H*C
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(entity, id); yd=NafPM
} ]39])ul
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publicList findAll(finalClass entity){ n_9Wrx328
return getHibernateTemplate().find("from 5>\Lk>rI
!Bu=?gf
" + entity.getName()); O-uf^S4
} #&sw%CD
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publicList findByNamedQuery(finalString Xh?J"kjof
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namedQuery){ MwE^.6xl{
return getHibernateTemplate ,>3b|-C-
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().findByNamedQuery(namedQuery); XjFaP {
} 4(mRLr%l@`
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publicList findByNamedQuery(finalString query, ],|;
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finalObject parameter){ 9i`MUE1Sh
return getHibernateTemplate p)c"xaTP#F
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().findByNamedQuery(query, parameter); k
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} SYYg
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publicList findByNamedQuery(finalString query, k =
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finalObject[] parameters){ R<Uu(-O-
return getHibernateTemplate y.aeXlc[
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().findByNamedQuery(query, parameters); uB;PaZG?{
} SU7 erCHX
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publicList find(finalString query){ zgPUW z
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return getHibernateTemplate().find }JM02R~I
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(query); ,|^ lqY
} jRBKy8?[C
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publicList find(finalString query, finalObject \E8CC>Jd
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parameter){ 8,&pX ga
return getHibernateTemplate().find 1$v1:6
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(query, parameter); 1#V&'A
} oV;I8;#\J
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public PaginationSupport findPageByCriteria #@Rtb\9
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(final DetachedCriteria detachedCriteria){ 0czEA
return findPageByCriteria BDcA_=^R&
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kv
(detachedCriteria, PaginationSupport.PAGESIZE, 0); O[5u6heNMr
} JL=s=9N;3
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public PaginationSupport findPageByCriteria df8aM<&m3
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(final DetachedCriteria detachedCriteria, finalint X8~gLdv8
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startIndex){ PS/00F/Ak
return findPageByCriteria FQBAt0
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(detachedCriteria, PaginationSupport.PAGESIZE, n_S)9C'=
9t"/@CH{
startIndex); NaC}KI`
} %-O[%Dy
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public PaginationSupport findPageByCriteria JU!vVA_
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(final DetachedCriteria detachedCriteria, finalint a+e8<fM yT
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pageSize, WoDQg64
finalint startIndex){ ^ Iy'<J
return(PaginationSupport) E-b3#\^:
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getHibernateTemplate().execute(new HibernateCallback(){ 9 UcSQ"D
publicObject doInHibernate #TD0)C/
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(Session session)throws HibernateException { *6QmYq6c<
Criteria criteria = c n^z=?
u= ydX
detachedCriteria.getExecutableCriteria(session); Wu
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int totalCount = ='vkd=`Si
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((Integer) criteria.setProjection(Projections.rowCount ,H:{twc
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()).uniqueResult()).intValue(); |YK4V(5x
criteria.setProjection !--A"
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(null); g6(u6%MD
List items = zf?U q
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criteria.setFirstResult(startIndex).setMaxResults 0RkiD8U5
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(pageSize).list(); (db4.G+0
PaginationSupport ps = 7gP8K`w?[
t(\P8J
new PaginationSupport(items, totalCount, pageSize, rhO8 v
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startIndex); |C3~Q{A
return ps; {on+
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} Jsw%.<
}, true); Bw*6X`'Q
} /]hE?cmj
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public List findAllByCriteria(final YY9Ub
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DetachedCriteria detachedCriteria){ )NCSO b
return(List) getHibernateTemplate Qhsk09K_=4
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().execute(new HibernateCallback(){ >n6yKcjY]
publicObject doInHibernate #NR9\
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(Session session)throws HibernateException { :yE7jXB
Criteria criteria = v@;!fBUt
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detachedCriteria.getExecutableCriteria(session); P'p5-l UK
return criteria.list(); #hP&;HZ2>"
} _%6Vcy
}, true); d ~3GEK
} N
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public int getCountByCriteria(final DgRA\[c
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DetachedCriteria detachedCriteria){ h0n,WU/Kw
Integer count = (Integer) )ZQML0}P;
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getHibernateTemplate().execute(new HibernateCallback(){ 6n5>{X
publicObject doInHibernate HA::(cXL
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(Session session)throws HibernateException { us3fBY'
Criteria criteria = pi?[jU[Tn
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detachedCriteria.getExecutableCriteria(session); o7WK"E!pF'
return r4(Cb_
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criteria.setProjection(Projections.rowCount P},d`4Ty@
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()).uniqueResult(); fY{&W@#g
} 'k9dN
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}, true); OX*5 yT{
return count.intValue(); xXm:S{I
} Lyj0$wbH`
} 2$%E:J+2:$
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用户在web层构造查询条件detachedCriteria,和可选的 +/Q?<*[
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 +7|Q d}\X
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PaginationSupport的实例ps。 E2a00i/9Y
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ps.getItems()得到已分页好的结果集 _;yi/)-2
ps.getIndexes()得到分页索引的数组 cp\A
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ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 p.J+~s4G
ps.getNextIndex()下一页索引 <4QOjW
ps.getPreviousIndex()上一页索引 T%p/(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g4fe(.?c,
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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 "8|a4Y+F
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一下代码重构了。 }xE}I<M
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我把原本我的做法也提供出来供大家讨论吧: 0zvA>4cq)
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首先,为了实现分页查询,我封装了一个Page类: F"*.Qq
java代码: dDoKmuY>5
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/*Created on 2005-4-14*/ M7 Z9(3Va
package org.flyware.util.page; Q-,,Kn
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/** }3&~YBx;:
* @author Joa #0wH.\79
* %Yi^{ZrM
*/ pg;y\}
publicclass Page { 2|C(|fD4
"/MA.zEl0,
/** imply if the page has previous page */ b\^q9fy
privateboolean hasPrePage; `[*n UdG
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/** imply if the page has next page */ $<N!2[I L
privateboolean hasNextPage; RN0=jo!58
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/** the number of every page */ <#r/4a"V
privateint everyPage; *tD`X(K
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/** the total page number */ LAT%k2%Wx
privateint totalPage; 3?rYt:Uf!
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/** the number of current page */ 8^FAeV#
privateint currentPage; F3L'f2yBG
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/** the begin index of the records by the current QIg.r\>o
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query */ />,Tq!i\4}
privateint beginIndex; SpB\kC"K
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/** The default constructor */ FNyr0!t,
public Page(){ Bh\>2]~@a
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} :jc
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/** construct the page by everyPage f;w7YO+$p9
* @param everyPage ^*fZ
* */ :GaK.W
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public Page(int everyPage){ iO,_0Y4
this.everyPage = everyPage; D@cv{
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} O0Vtvbj
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/** The whole constructor */ And|T 6u
public Page(boolean hasPrePage, boolean hasNextPage, }>|M6.n "
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} 9qbF+b
int everyPage, int totalPage, ?pAO?5Z:}
int currentPage, int beginIndex){ Vif0z*\e{
this.hasPrePage = hasPrePage; ;GgW&*|
this.hasNextPage = hasNextPage; =QiVcw,G#
this.everyPage = everyPage; )t-Jc+*A>
this.totalPage = totalPage; GWU"zWli]z
this.currentPage = currentPage; W]t!I}yPR
this.beginIndex = beginIndex; cxNb!G
} ba-J-G@YW
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/** <e
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* @return M,ObzgW
* Returns the beginIndex. covr0N)
*/ W_##8[r(?
publicint getBeginIndex(){ EM.7,;|N
return beginIndex; X}/{90UD
} r[TTG0|
7%E]E,f/#
/** D_HE!fl
* @param beginIndex ia!b0*<
* The beginIndex to set. EAg Nu?L
*/ SREe,
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publicvoid setBeginIndex(int beginIndex){ nlfu y[oX
this.beginIndex = beginIndex; U60jkzIRH
} */|Vyp-
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/** ZDI%?.U
* @return P a{)@xT
* Returns the currentPage. J*lKXFq7
*/ sU/R$Nbr
publicint getCurrentPage(){ |Mm9QF;iA
return currentPage; =ca<..yh[d
} WI?iz-,](
7I,/uv?
/** L6xLD X7y
* @param currentPage ;m;a"j5
* The currentPage to set. Oh\+cvbG
*/ :a 5#yh
publicvoid setCurrentPage(int currentPage){ G9/5KW}-
this.currentPage = currentPage; /-.i=o]b
} &@c?5Ie5
vtv^l3
/** JVoW*uA
* @return $E_9AaX
* Returns the everyPage. }[[
*/ vu&%e\gM
publicint getEveryPage(){ Zj*kHjn"
return everyPage; ]$StbBP
} cPemrNxydN
;}tEU'&
/** v[aFSXGj)
* @param everyPage : DxCjv
* The everyPage to set. hr+,-j
*/ x}`]9XQ
publicvoid setEveryPage(int everyPage){ qm.30 2
this.everyPage = everyPage; +EmT+$>J
} nj (/It
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/** {EoRY/]
* @return #q06K2
* Returns the hasNextPage. uA}w?;
*/ <O5r|
publicboolean getHasNextPage(){ ,Tb~+z|-[
return hasNextPage; wX0m8"g@
} 5&y;r
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/** U%Kv}s/(F{
* @param hasNextPage D*>EWlZ
* The hasNextPage to set. urlwn*!^s
*/ (|6Y1``
publicvoid setHasNextPage(boolean hasNextPage){ LEq"g7YH
this.hasNextPage = hasNextPage; W-QBC-
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} nPW?DbH +
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/** 'E4`qq
* @return ^l UV^%f
* Returns the hasPrePage. d ,Fj|}S
*/ oBA]qI
publicboolean getHasPrePage(){ H O^3v34ZO
return hasPrePage; ~{#$`o=
} >t[beRcR6
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/** U5 `h
* @param hasPrePage GAZTCkB"
* The hasPrePage to set. [3yzVcr~4
*/ G2bZl%
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publicvoid setHasPrePage(boolean hasPrePage){ +>em
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this.hasPrePage = hasPrePage; hnQDm$k
} i/&?e+i
>|)ia5#
/** K/2k/\Jk[_
* @return Returns the totalPage. d 6$,iw@>^
* 14[+PoF^A
*/ `]Uu` b
publicint getTotalPage(){ 6 9 PTo
return totalPage; 'f#i@$|]
} +<G |Ru-
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/** @}
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* @param totalPage B? Vr9H 7n
* The totalPage to set. S~dD ;R
*/ KjrUTG0oA
publicvoid setTotalPage(int totalPage){ ~wMdk9RQ
this.totalPage = totalPage; BFU6?\r
} g>lJZD@
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} fn%Gu s~
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 iqzl (9o.D
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个PageUtil,负责对Page对象进行构造: F{#m~4O
java代码: LQ,RQ~!
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/*Created on 2005-4-14*/ 4"OUmh9LHB
package org.flyware.util.page; E<[_L!2
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import org.apache.commons.logging.Log; bYuQ"K
A$
import org.apache.commons.logging.LogFactory; 0_}^IiG
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/** [0_JS 2KE
* @author Joa `EV"
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* a@|/D\C
*/ R^}}-Dvr
publicclass PageUtil { G}o?lo\#h
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privatestaticfinal Log logger = LogFactory.getLog e&Z\hZBb
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(PageUtil.class); Wq bfZx
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/** }PZz(Ms
* Use the origin page to create a new page R&w2y$
* @param page c0J=gZiP
* @param totalRecords $jt UQ1
* @return pK)*{fC$`
*/ p^2"g~
publicstatic Page createPage(Page page, int i\P?Y(-{
- nWs@\
totalRecords){ :NB,Dz+i
return createPage(page.getEveryPage(), }E01B_T9z
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page.getCurrentPage(), totalRecords); ep"YGx[V
} 64Ot`=A"
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/** h)%}O.ueB
* the basic page utils not including exception Wvhg:vup
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handler '64&'.{#>r
* @param everyPage >28.^\?H4
* @param currentPage GZ L{~7n
* @param totalRecords RwH<JaL:
* @return page |{#=#3X
*/ T5mdC
publicstatic Page createPage(int everyPage, int .YvE
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currentPage, int totalRecords){ Km~\^(a '
everyPage = getEveryPage(everyPage); ya81z4?
currentPage = getCurrentPage(currentPage); 1B;-ea
int beginIndex = getBeginIndex(everyPage, V:M$-6jv
'Ii%/ Ob!
currentPage); (BtavE
int totalPage = getTotalPage(everyPage, 5lp
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totalRecords); {x{/{{wzv
boolean hasNextPage = hasNextPage(currentPage, Yp8~wdm
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totalPage); btq`[gAF\
boolean hasPrePage = hasPrePage(currentPage); KFCL|9P
>".,=u'
returnnew Page(hasPrePage, hasNextPage, ]J^9iDTTA
everyPage, totalPage, .s4hFB^n
currentPage, U] 2fV|Hn
+k!Y]_&(:f
beginIndex); r]x;JBy
}
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privatestaticint getEveryPage(int everyPage){ H'Mc]zw_,
return everyPage == 0 ? 10 : everyPage; zj!&12w%3
} $#4J^(I*:
5XO eYO{
privatestaticint getCurrentPage(int currentPage){ +ahr-v^R<
return currentPage == 0 ? 1 : currentPage; MC.,n$O}6
} $}d| ~q\
Onr#p4UT
privatestaticint getBeginIndex(int everyPage, int Da)rzr|}>3
Zk+J= Cwq}
currentPage){ T-Od|T@[
return(currentPage - 1) * everyPage; { VC4rA
} &9CKI/K:
!P7##ho0
privatestaticint getTotalPage(int everyPage, int -.A8kJ
p100dJvq
totalRecords){ 20hF2V
int totalPage = 0; sSLs%)e|:
c5uT'P"
if(totalRecords % everyPage == 0) {}?;|&_
totalPage = totalRecords / everyPage; 0A%>'<
else Z+!3m.q
totalPage = totalRecords / everyPage + 1 ; aqvt$u8
>3H/~ Y
return totalPage; myT z
} NIeKS_ +
!HA[:-JCz
privatestaticboolean hasPrePage(int currentPage){ +):t6oX|
return currentPage == 1 ? false : true; +"Pt? k
} RU!j"T
5
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S@
privatestaticboolean hasNextPage(int currentPage, Sd;/yC 8
3F,$}r#
int totalPage){ e&dE>m
return currentPage == totalPage || totalPage == QN[-XQ>Xt
)hH9VGZq(
0 ? false : true; GyV3 ]Qqj
} !F0MLvdX7^
wj>mk
aa<9%j
} qC9$xIWq
^/K\a
,
j(|G) F
9Vx2VjK2'
IVYWda0m
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。 QDlEby m
o5 6_t{<
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 !1f8~"Z
hWK}] gF
做法如下: W G2 E3y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 JZp*"UzQr
)^UM8
s
的信息,和一个结果集List: \H$Ps9Xh
java代码: !dfc1 UjB
*|MHQp'A
V\zf yH\~
/*Created on 2005-6-13*/ Wvl>i HB
package com.adt.bo; OYGh!sW
(yFR;5Fo
import java.util.List; PMk3b3)Z
^5TSo&qZ
import org.flyware.util.page.Page; C+-GE9=
hR3lo;'
/** l-"c-2-!
* @author Joa aH)$#6${Ap
*/ 3kFOs$3
publicclass Result { 7s_#X|A$
&H!3]
private Page page; [B9'/:
NLFSw
private List content; 0bxB@(NO
3X$)cZQ
/** k LVf}J~?
* The default constructor _Zya GDv
*/ !3>(fj+QS
public Result(){ <@FOqi{o{
super(); <Vyv)#32o3
} orn9;|8q
oxE'u<
/** ;crQ7}k
* The constructor using fields ;bVC7D~~4w
* ig:/60Z
* @param page mH>oF|
* @param content U0'> (FP~2
*/ 8YC\Bw
public Result(Page page, List content){ >ir'v5
this.page = page; M:|Z3p K
this.content = content; H8~<;6W
} J#B%
#X
{S(d5o8
/** E4RvVfA0F
* @return Returns the content. C.V")D=
*/ [-!
publicList getContent(){ I_@\O!<y}
return content; }}XYV eI
} e Ll+F%@
~vnG^y>%
/** e2Sm.H '
* @return Returns the page. LtKiJ.j?A
*/ t3K7W2bz
public Page getPage(){ D.o|pTZ
return page; }f np}L
} kf+]bV
MZf$8R
/** 6Y6DkFdvrZ
* @param content {g}!M^|
* The content to set. 6V\YYrUz
*/ S (](C
public void setContent(List content){ $5y%\A
this.content = content; %pgie"k
} tLe!_p)
Q=J"#EFs
/** f7 V3 6Q8
* @param page ZzLmsTtzIu
* The page to set. $8o(_8Q)
*/ \|nF55W [
publicvoid setPage(Page page){ 1"3|6&=
this.page = page; ^RytBwzKM
} Rk.YnA_J6
} Rkm1fYf
WS8m^~S@\
)%x oN<
emOd<C1A
x/Se
/C
2. 编写业务逻辑接口,并实现它(UserManager, [Hz_x(t26
0ZPwEP
UserManagerImpl) 9tsI1]1[m
java代码: /kE3V`es
9@
[R>C
zu'Uau
/*Created on 2005-7-15*/ Ql
a'vcT
package com.adt.service; j*>+^g\Q6
Kdk0#+xtP
import net.sf.hibernate.HibernateException; 1eQ9(hzF
Sj;B1&
import org.flyware.util.page.Page; [hA%VF.9
"l!WO`.zp=
import com.adt.bo.Result; ?>5[~rMn
GqumH/;
/** i`/_^Fndyu
* @author Joa q\ FF)H
*/ ES!$JWK|
publicinterface UserManager { /PG+ s6
=3OK3|
public Result listUser(Page page)throws km2('t7?
;LE4U OK
HibernateException; }r$&"wYM
q65KxOf`
} $E3-</ f
e*p7(b-
zWpJ\/k~
zbK=yOIOd
/^^t>L
java代码: XL@i/5C[
~K}iVX
$2qZds[
/*Created on 2005-7-15*/ R06L4,/b
package com.adt.service.impl; )I'?]p<
C( 8i0(1
import java.util.List; W[BZ/
)=l~XV
import net.sf.hibernate.HibernateException; "a))TV%N
6nh!g
import org.flyware.util.page.Page; |niYN7 17
import org.flyware.util.page.PageUtil; B*7Y5_N
xgHR;USH
import com.adt.bo.Result; "MHm9D?5
import com.adt.dao.UserDAO; Y$hYW
import com.adt.exception.ObjectNotFoundException; ~$n4Yuu2[
import com.adt.service.UserManager; `v3WJ>Q!N?
H-A?F^#
/** |D+"+w/
* @author Joa d4KTwn5g
*/ I Wcgh`8
publicclass UserManagerImpl implements UserManager { OV3l)73?t
v+uq
private UserDAO userDAO; HE58A.Q&
D ]Q,~Y&'
/** xY9#ouF
* @param userDAO The userDAO to set. Fb=(FQ2Y?
*/ k#Qav1_
publicvoid setUserDAO(UserDAO userDAO){ bA}9He1
this.userDAO = userDAO; 4-;"w;
} {Q],rv|;
FY_.Vp
/* (non-Javadoc) d%_=r." Y
* @see com.adt.service.UserManager#listUser 6 "fYSn>
Q ^X
(org.flyware.util.page.Page) |{W4JFKJ
*/ ly"Jl8/<
public Result listUser(Page page)throws pgbm2mT9
4?Pdld
HibernateException, ObjectNotFoundException { FJ0Ity4u6
int totalRecords = userDAO.getUserCount(); gU\pP,a
if(totalRecords == 0) CXt9 5O?
throw new ObjectNotFoundException %@tKcQ
O
]o7
("userNotExist"); MB.\G.bV
page = PageUtil.createPage(page, totalRecords); &_Kb;UVRj
List users = userDAO.getUserByPage(page); j6v|D>I
returnnew Result(page, users); -!MrG68
}
Fj Rt'
/(IV+
} 8G$ %DZ $
m(CW3:|
j1{|3#5V
d 90
3FRz&FS:j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 p3>(ZWPNV
)_bc:6Q
询,接下来编写UserDAO的代码: '%Og9Bgd+
3. UserDAO 和 UserDAOImpl: MMlryn||1
java代码: kQ~2mU
{!!df.h
E;!pK9wL|
/*Created on 2005-7-15*/ $A~UA
package com.adt.dao; zVN/|[KP4
GL;@heP
import java.util.List; y/=:F=H@w
:})(@.H
import org.flyware.util.page.Page; yg({g
"
m$<LO%<~p
import net.sf.hibernate.HibernateException; HYVSi3[
MKVz'-`u
/** tGt/=~n9
* @author Joa iMG)zPj
*/ %smQ`u|
publicinterface UserDAO extends BaseDAO { ^(z7?T
.OhpItn
publicList getUserByName(String name)throws VB>KT(n-b
|;xm-AM4r
HibernateException; A/5??3H
fM,!9}<
publicint getUserCount()throws HibernateException; e7e6b-"_2
<Z{pjJ/
publicList getUserByPage(Page page)throws FY;\1bt<<
MTBHFjXO
HibernateException; k3[rO}>s
u.v
5!G
} #,dNhUV#
?%RAX CK
be&5vl
L8OW@)|
6Gt~tlt:L
java代码: 9%fd\o@X
oCtg{*vp
$cl[Qcw
/*Created on 2005-7-15*/ ;]*V6!6RR
package com.adt.dao.impl; wQ1_Q8 :Z
'Br:f_}
import java.util.List; y 98v
s|er+-'
import org.flyware.util.page.Page; qHwHP 1
'ec G:B`S
import net.sf.hibernate.HibernateException; (!b_o A8V
import net.sf.hibernate.Query; UI:YzR
SZUhZIz&
import com.adt.dao.UserDAO; \YUl$d0
)m8ve)l
/** [3$L}m
* @author Joa H CBZ*Z-
*/ FHztF$Z
public class UserDAOImpl extends BaseDAOHibernateImpl "ijpqI
EY~b,MIL4
implements UserDAO { 4%! #=JCl
(<M^C>pldf
/* (non-Javadoc) ?yAp&Ad
* @see com.adt.dao.UserDAO#getUserByName zk6al$3R
RYhaQ&1i
(java.lang.String) $~>3bik@
*/ a[e&O&Z
publicList getUserByName(String name)throws [tN^)c`s/
0*e)_l!
HibernateException { oJ\)-qSf
String querySentence = "FROM user in class (CUrFZT$
1Yr&E_5/
com.adt.po.User WHERE user.name=:name"; N5W;Zx]
Query query = getSession().createQuery b5!\"v4c
NO$n-<ag
(querySentence); |E{tS,{OhJ
query.setParameter("name", name); ]JGh[B1gh
return query.list(); FEOr'H<3x
} L >*
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+SM&_b
/* (non-Javadoc) 9gu$vF]9!
* @see com.adt.dao.UserDAO#getUserCount() w$5~'Cbi
*/ !v/j*'L<M}
publicint getUserCount()throws HibernateException { O$dcy!
int count = 0; 0 QzUcr)3+
String querySentence = "SELECT count(*) FROM
ywQ>T+
iJ8 5okv'
user in class com.adt.po.User"; 8PN/*Sa
Query query = getSession().createQuery 0P MF)';R
"zN2+X"&
(querySentence); :ik$@5wp
count = ((Integer)query.iterate().next Z)V m,ng
3o).8b_3g
()).intValue(); Vgh;w-a
return count; Z)JJ-V!
} |AosZeO_
~Onj|w7
/* (non-Javadoc) 72i]`
* @see com.adt.dao.UserDAO#getUserByPage -|1H-[Y(
w@K4u{|
(org.flyware.util.page.Page) W|~Jl7hs8Q
*/ #=}dv8
publicList getUserByPage(Page page)throws =O~ J
sObH#/l`
HibernateException { 7z.(pg=
String querySentence = "FROM user in class O~p@87aq
}"$2F0
com.adt.po.User"; A~2U9f+\
Query query = getSession().createQuery t>f61<27eB
FWi c/7
(querySentence); g&79?h4UXQ
query.setFirstResult(page.getBeginIndex()) t h!$R
.setMaxResults(page.getEveryPage()); bHJKX>@{
return query.list(); uq/z.m
} m7dpr$J
`5HFRgL`.
} 0n FEPMO
VXE85
\vH /bL
G<F+/Oi&DX
>M}\_c=
至此,一个完整的分页程序完成。前台的只需要调用 | c:E)S\
R04%;p:k#
userManager.listUser(page)即可得到一个Page对象和结果集对象 k!&G; 6O-
|igr3p5Fw
的综合体,而传入的参数page对象则可以由前台传入,如果用 PIZnzZ@Z;
"7]YvZYu0
webwork,甚至可以直接在配置文件中指定。 >DFpL$oP
n;Nr[hI
下面给出一个webwork调用示例: *qX!
java代码: p"xti+2,
o{W4@:Ib
R*"31&3le4
/*Created on 2005-6-17*/ Qkk3>{I
package com.adt.action.user; +*W9*gl
3 s @6pI
import java.util.List; ^)JUl!5j]C
|8QXjzH
import org.apache.commons.logging.Log; 2H,^i,
import org.apache.commons.logging.LogFactory; sIVVF#0}]
import org.flyware.util.page.Page; Q140b;Z
Sckt gp8
import com.adt.bo.Result; DH@]d0N
import com.adt.service.UserService; O^Y}fo'
import com.opensymphony.xwork.Action; =up!lg^M
\d"uR@$3mG
/** T[~8u9/
* @author Joa A#b`{C~l
*/ *btLd7c%
publicclass ListUser implementsAction{ Q|gw\.]$&[
X@["Jjp
privatestaticfinal Log logger = LogFactory.getLog Z+gG.|"k
'8k{\>
(ListUser.class); '7Ad:em
A^m]DSFOO
private UserService userService; ;^[VqFpeS
UQ7E7yY#
private Page page; FnZMW, P
%OV)O -
privateList users; jX9{Ki"
g9T9TQ-O
/* C >@T+xOZ
* (non-Javadoc) ak SUk)}e
* sI/]pgt2
* @see com.opensymphony.xwork.Action#execute() \zdY$3z
*/ _`oP*g =
publicString execute()throwsException{ hc2AGeZr
Result result = userService.listUser(page); >}uDQwX8
page = result.getPage(); ?k|}\l[X1
users = result.getContent(); D2,2Yy5y
return SUCCESS; NcuZw?
} #mK/xbW
:jKiHeBQu?
/** F6L}n-p5
* @return Returns the page. -T,/S^
*/ Y%OJ3B(n|
public Page getPage(){ (O[:-Aqm
return page; `rwzCwA1
} N!W# N$
5xS
ze;
/** X\=m
* @return Returns the users. ytmFe !
*/ @nh*H{
publicList getUsers(){ O BCH%\;g
return users; 7_=7 ;PQ<
} FX->_}kL=
2!w5eWl,
/** Juhi#&`T
* @param page #1-2)ZO.
* The page to set. _EusY3q
*/ |}FK;@'I 6
publicvoid setPage(Page page){ rnkq.
this.page = page; lI)RaiMr=
} pv}k=wqJ1
t+H=%{z
/** \{GBaMwG~
* @param users vMlT
* The users to set. g?9IS,Gp
*/ .`ND
publicvoid setUsers(List users){ QE#Ar8tU
this.users = users; G
$F3dx.I
} San=E@3}v!
G\;a_]Q
/** ytDp
4x<W)
* @param userService 76} a
* The userService to set. z5>
{(iY;,
*/ z_ 01*O
publicvoid setUserService(UserService userService){ pBb fU2p
this.userService = userService; >RTmfV
} 2#XYR>[
} Jc3Z1 Tt
hoDE*>i
+H4H$H
N Dqvt$
C4].egVg
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, "44A#0)B'l
NI%&Xhn!*>
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 Cj +{%^#
H}p5qW.tH:
么只需要: @:ojt$
java代码: nZtP!^#
D,c53B6M
'G#T 6B!
<?xml version="1.0"?> ^p}S5,
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Q ,`R-?v
ULJV
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Ch;wvoy
c*@#0B
1.0.dtd"> "R!)"B==
^W*T~V*8
<xwork> &yabxl_
e -yL
<package name="user" extends="webwork- e Lj1
f~rq)2V:
interceptors">
W>HGB
2C&G'@>
<!-- The default interceptor stack name AWG;G+
O'i!}$=g
--> O^L#(8bC
<default-interceptor-ref w y\0o
J?1U'/Wx2
name="myDefaultWebStack"/> "J_#6q*
p!_3j^"{
<action name="listUser" [2l2w[7Rid
<aPbKDF~V
class="com.adt.action.user.ListUser"> nRSiW*;R
<param l`wF;W!
Y+kfMA v
name="page.everyPage">10</param> m) -DrbE
<result JHvawFBN<u
"dItv#<:}
name="success">/user/user_list.jsp</result> ^{m&2l&87
</action> :,f~cdq=
;dR4a@
</package> ALO0yc
})#SjFq<V
</xwork> iL6Yk @
y+"6Y14
*i)3q+%.
Af`qe+0E
6`JY:~V"
Ob~7r*q
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 bZKlQ<sI
6]D%|R,Q#}
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。 h@H8oZ[
IHs^t/;Iv
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 F^/b!)4X
f7y3BWOi]
L#>^R
4]P5k6nV
ToXgl4:kd
我写的一个用于分页的类,用了泛型了,hoho !VoAN5#;
R2`-*PZ_
java代码: (]}52%~
]aDU* tk
?\.DG`Zxc
package com.intokr.util; D00v"yp%%
K
K_
import java.util.List; %0MvCm
G oHdhne3
/** +;|" #
* 用于分页的类<br> |vUjoa'.7E
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~#SLb=K
* _ mJP=+i
* @version 0.01 O`rKxP
* @author cheng _Xe"+
*/ mFa%d8Y
public class Paginator<E> { \kS:u}Ip!
privateint count = 0; // 总记录数 oz[Mt
i*
privateint p = 1; // 页编号 H-g
CY|W
privateint num = 20; // 每页的记录数 |3SM
privateList<E> results = null; // 结果 "+{>"_KV
,|lDR@
/** $E,,::oJ
* 结果总数 ,Qb(uirl]
*/ B_3:.1>"BM
publicint getCount(){ J4l\
return count; vS1#ien#
} 02RZ>m+
CUI\:a-
publicvoid setCount(int count){ K4w#}gzok
this.count = count; N7l`-y
} <uKd)l
ZdsYIRU#
/** @GyxOc@6
* 本结果所在的页码,从1开始 ~^ <1k-
* I8%Uyap{
* @return Returns the pageNo. $eU oFa5A
*/ 5BAGIO<w
publicint getP(){ dZ6P)R
return p; 6Qw5_V^0o
} vLT$oiN[c
kwAL]kI
/** QMQ\y8E
* if(p<=0) p=1 r
Y#^C
* 0n)99Osq(u
* @param p vjz 'y[D
*/ AL{r/h
publicvoid setP(int p){ hVe39BBtO
if(p <= 0) ,u@Vi0
p = 1; ]Dd}^khv
this.p = p; ur@"wcl"V
} U'oFW@Y;h
UfxYD
/** !+H)N
* 每页记录数量 >X58 zlxk
*/ G4jyi&]
publicint getNum(){ (
C~ u.
return num; =#so[Pd
} SsBiCctn
G5!J9@Yi
/** j#rj_ uP
* if(num<1) num=1 m3']/}xHO
*/ EpUBO}q]
publicvoid setNum(int num){ $)v`roDD.
if(num < 1) 0=erf62=
num = 1; w'Vm'zo
this.num = num; .EB'n{zxd
} IZSJ+KO
<nk7vo?Ks
/** e anR$I;Yj
* 获得总页数
<_>xkQbn2
*/ <_ruVy0]
publicint getPageNum(){ {^*K@c
return(count - 1) / num + 1; j0uu*)Rk
} u5O`|I@R
S9kA69O
/** N?j#=b+D
* 获得本页的开始编号,为 (p-1)*num+1 lK"m|Z
*/ $VNj0i. Pr
publicint getStart(){ yR$ld.[uf
return(p - 1) * num + 1; jzb%?8ZJ
} |6o!]~&e$1
pybE0]
/** #<o=W#[
* @return Returns the results. X4dxH_@
*/ ^hRx{A
publicList<E> getResults(){ ojG;[@V
return results; K'f`}y9
} MJugno
7wz9x8 \t
public void setResults(List<E> results){ S3N+9*iK
this.results = results; A81'ca/
} wmDO^}>ZP
59#o+qo4
public String toString(){ _uq[D`=
StringBuilder buff = new StringBuilder :x[SV^fw[
ep)O|_=
(); H~<w*[uT
buff.append("{"); Yow
buff.append("count:").append(count); yB5JvD ?
buff.append(",p:").append(p); 4'#?"I
buff.append(",nump:").append(num); OVUJiBp
buff.append(",results:").append vJ9IDc|[
/I48jO^2
(results); {JlSfJw!
buff.append("}"); qtlcY8!
return buff.toString(); L]Dq1q8`
} A/TCJ#>l
CNl @8&R
} wBI>H
7A
A/sM
?!p>_
aL^
58M y&