Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7!` C TE
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 XyKKD&j
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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 D;
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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 $HR(|{piZ
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分页支持类: SjNwT[.nr7
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java代码: e5:l 6`
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package com.javaeye.common.util; 5e~{7{
#/
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import java.util.List; S|u1QGB
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publicclass PaginationSupport { V }r_
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publicfinalstaticint PAGESIZE = 30; cvLcre% >A
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privateint pageSize = PAGESIZE; hnfrnYH
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privateList items; 3vvFF]D5k
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privateint totalCount; #\!hBL
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privateint[] indexes = newint[0]; [7Kj$PB3
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privateint startIndex = 0; q_m#BE;t
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public PaginationSupport(List items, int -^nQ^Td=j
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totalCount){ N4GIb 6
setPageSize(PAGESIZE); uzn))/"
setTotalCount(totalCount); JXa%TpI:
E
setItems(items); N6 }i>";_;
setStartIndex(0); kI1{>vYD
} %_X[{(
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public PaginationSupport(List items, int 4@V <Suw
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totalCount, int startIndex){ )*QTxN
setPageSize(PAGESIZE);
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setTotalCount(totalCount); +
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setItems(items); `a1R "A
setStartIndex(startIndex); q'8@0FT0
} A"T. nqB^y
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public PaginationSupport(List items, int cE8 _keR~
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totalCount, int pageSize, int startIndex){ d-S'y-V?d
setPageSize(pageSize); PFn[[~5V
setTotalCount(totalCount); 6s"bstc{
setItems(items); *]UEF_
setStartIndex(startIndex); JMe[
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} fm2M i~}0
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publicList getItems(){ p-03V"^&
return items; kGTc~p(
} Vgb>3]SU
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publicvoid setItems(List items){ 3b/vyZF
this.items = items; DDCQ Af
} vYm&AD
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publicint getPageSize(){ v}*u[GWl]
return pageSize; N)I
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} PHL@1K{)
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publicvoid setPageSize(int pageSize){ >yHnz?bf@
this.pageSize = pageSize; Q1&dB{L
} B+H9c~3$
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publicint getTotalCount(){ /WgW e
return totalCount; T|iF/p]F
} -v+^x`HR
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publicvoid setTotalCount(int totalCount){ 5 9J$SE
if(totalCount > 0){ umn~hb5O
this.totalCount = totalCount; %_=R&m'n`
int count = totalCount / U=#ylQ
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pageSize; U$JIF/MO_
if(totalCount % pageSize > 0) Jt,
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count++; s=@CeV@4W
indexes = newint[count]; Ewsg&CCN
for(int i = 0; i < count; i++){ I\6<)2j/L
indexes = pageSize * DT]p14@t9
}
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} Z!l!3(<G.f
}else{ 2}C>{*}yQ
this.totalCount = 0; J0W).mD_H
} Ck a]F2,
} c89vx 9
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publicint[] getIndexes(){ |(ju!&
return indexes; "LaX_0t)
} uiEA=*axp
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publicvoid setIndexes(int[] indexes){ l5nDt$Ex
this.indexes = indexes; 05LQh
} ?v~3zHK
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publicint getStartIndex(){ xVX||rrh
return startIndex; ]c=1-Rl
} 0BD((oNg
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publicvoid setStartIndex(int startIndex){ &+iW:
if(totalCount <= 0) D)Rf
this.startIndex = 0; 0lh6b3tdP
elseif(startIndex >= totalCount) yC*B OJS
this.startIndex = indexes zW`koRH@
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[indexes.length - 1]; cyeDZ)
elseif(startIndex < 0) 0\^2HjsJ
this.startIndex = 0; p+D6Z'B
else{ sBI%lrO
this.startIndex = indexes !T(Omve)
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[startIndex / pageSize]; = }lA|S
} ;7*@Gf}R
} 7f,WzvV
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publicint getNextIndex(){ ~y^lNgujO
int nextIndex = getStartIndex() + s""8V_,;
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pageSize; Dx)XC?'xO
if(nextIndex >= totalCount) 'Rw]
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return getStartIndex(); lc#zS_
else P;/wb/
return nextIndex; %-|q3 ^s
} bu9&sQ;
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publicint getPreviousIndex(){ 0J</`/g H
int previousIndex = getStartIndex() - B;_3IHMO
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pageSize; #;]F:TlR
if(previousIndex < 0) Q
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return0; HN@)/5BY
else a/#,Y<kJ
return previousIndex; UH|.@7w
} T^G<)IX`c
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} MX\-)e#
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抽象业务类 4 Z)]Cq*3
java代码: f`rz)C03
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/** AE
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* Created on 2005-7-12 HE'8
*/ y@JYkp>I
package com.javaeye.common.business; >L4$DKO
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import java.io.Serializable; h!GixN?
import java.util.List; XePBA
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import org.hibernate.Criteria; +,>bpp1
import org.hibernate.HibernateException; D<6kAGE
import org.hibernate.Session; 5Vqvb|
import org.hibernate.criterion.DetachedCriteria; HpAZ{P7
import org.hibernate.criterion.Projections; *X=-^\G
import KL`>mJo$
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org.springframework.orm.hibernate3.HibernateCallback; tYa8I/HpT
import 0MPDD%TP
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org.springframework.orm.hibernate3.support.HibernateDaoS 2jC\yY |PN
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upport; yG4MqR)J
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import com.javaeye.common.util.PaginationSupport; _"V0vV
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public abstract class AbstractManager extends *[n^6)
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HibernateDaoSupport { *JXJ
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privateboolean cacheQueries = false; k3XtKPO
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privateString queryCacheRegion; =p6xc}N
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publicvoid setCacheQueries(boolean cqp#1oM4M
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cacheQueries){ RoZV6U~
this.cacheQueries = cacheQueries; JM%#L *;
} +dv@N3GV
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publicvoid setQueryCacheRegion(String ?|dz"=y
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queryCacheRegion){ }Jfo(j
this.queryCacheRegion = }JsdgO&z
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queryCacheRegion; *Rd&4XG
} ,L G&sa"
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publicvoid save(finalObject entity){ p3' +"sFU
getHibernateTemplate().save(entity); &EOh}O<
} Ui&$/%Z|
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publicvoid persist(finalObject entity){ %54![-@
getHibernateTemplate().save(entity); ~T~v*'_h
} 4{KsCd)
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publicvoid update(finalObject entity){ y]_DW6W
getHibernateTemplate().update(entity); p'*UM%@SIY
} 9iE66N>z
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publicvoid delete(finalObject entity){ 7F4]EA^
getHibernateTemplate().delete(entity); E.9F~&DPJ<
} DVl:s
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publicObject load(finalClass entity, Eqc$*=
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finalSerializable id){ 2}t wt
return getHibernateTemplate().load icmDPq
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(entity, id); }UrtDXhA
} xo$ZPnf(zv
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publicObject get(finalClass entity, `upNP/,
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finalSerializable id){ 51vK>
return getHibernateTemplate().get 5hAg*zJb5o
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(entity, id); )-@EUN0E>5
} !MC Wt
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publicList findAll(finalClass entity){ kokkZd7!
return getHibernateTemplate().find("from (EX
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" + entity.getName()); x-<dJ}`
} $H^6I8>
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publicList findByNamedQuery(finalString $gNCS:VG*
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namedQuery){ |zMQe}R@%
return getHibernateTemplate 8~i@7~
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().findByNamedQuery(namedQuery); (`xc3-,
} 'SmdU1]4BD
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publicList findByNamedQuery(finalString query, /Q!F/HY3ZS
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finalObject parameter){ abND#t
return getHibernateTemplate [H6>] &
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().findByNamedQuery(query, parameter); s@$AYZm_
} >BX_Bou
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publicList findByNamedQuery(finalString query, dY,'6JzC
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finalObject[] parameters){ 7XNfH@
return getHibernateTemplate "hfwj`U
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().findByNamedQuery(query, parameters); &a`-NRU#
} II91Ia
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publicList find(finalString query){ eZcm3=WV|
return getHibernateTemplate().find 89paR[
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(query); =BtEduz
} j!s&yHE1
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publicList find(finalString query, finalObject ?vVkZsU
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parameter){ 6]Jv3Re'(I
return getHibernateTemplate().find "#7i-?=
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(query, parameter); 4g 1h:I/
} $3L7R
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public PaginationSupport findPageByCriteria =N=,;<6%A
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(final DetachedCriteria detachedCriteria){ W{0:8_EI
return findPageByCriteria 3 yElN.=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); k2=uP8
} mT.F$Y9
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public PaginationSupport findPageByCriteria h2q]!01XP
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(final DetachedCriteria detachedCriteria, finalint 9K49<u0O
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startIndex){ h+Dok#g
return findPageByCriteria cZu:dwE
<fw[7=_)^
(detachedCriteria, PaginationSupport.PAGESIZE, ql#K72s
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startIndex); !hq7R]TC+
} v zn/waw
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public PaginationSupport findPageByCriteria bfJDF(=h
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(final DetachedCriteria detachedCriteria, finalint _ReQQti[
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pageSize, !-QKh aY
finalint startIndex){ Rwr0$_A
return(PaginationSupport) F4}Zl
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getHibernateTemplate().execute(new HibernateCallback(){ w
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publicObject doInHibernate +o/q@&v;Ax
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(Session session)throws HibernateException { 6+It>mnR
Criteria criteria = ~DJ/sY2/
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detachedCriteria.getExecutableCriteria(session); Kz%wMyZ:g
int totalCount = 4_mh
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((Integer) criteria.setProjection(Projections.rowCount HZ|6&9we
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()).uniqueResult()).intValue(); 4uz\Me(
criteria.setProjection {5to;\.
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(null); >fjf]
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List items = M*}o{E;
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criteria.setFirstResult(startIndex).setMaxResults [p<L*3<
3{%/1>+x5
(pageSize).list(); D\k);BU~
PaginationSupport ps = Ki' EO$
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new PaginationSupport(items, totalCount, pageSize, q%JV"9,
n\ IVpgP
startIndex); =v_ju;C=
return ps; T1x$v,)8x
} F;zmq%rK
}, true); U'\\(m|
} =3}+f-6"'
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public List findAllByCriteria(final d`:0kOF+
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DetachedCriteria detachedCriteria){ <q!{<(:
return(List) getHibernateTemplate >uQ!B/C!
7mu%| !
().execute(new HibernateCallback(){ {_
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publicObject doInHibernate N+r~\[N\9
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(Session session)throws HibernateException { P$!Ht
Criteria criteria = cJqPcCq(wn
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detachedCriteria.getExecutableCriteria(session); P017y&X
return criteria.list(); 4
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} jReI+
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}, true); (Q@m;i>
} o]]Q7S=
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public int getCountByCriteria(final >LW9$[H
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DetachedCriteria detachedCriteria){ 6Fm.^9@
Integer count = (Integer) >6aCBS?2
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getHibernateTemplate().execute(new HibernateCallback(){ ^ML2xh
publicObject doInHibernate A$-{WN.W
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(Session session)throws HibernateException { bT8BJY%+
Criteria criteria = HkQ2G}<
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detachedCriteria.getExecutableCriteria(session); K46mE
return QJv,@@mu
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criteria.setProjection(Projections.rowCount Y(&phv&
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()).uniqueResult(); mX<D]Z< k
} h IGa);g
}, true); ]qXfgc
return count.intValue(); [rQ#skf
} V,>#!zUv
} (OJ}|*\ e
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用户在web层构造查询条件detachedCriteria,和可选的 0a(*/u
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 p*>[6{$3)O
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PaginationSupport的实例ps。 (+4=A k
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ps.getItems()得到已分页好的结果集 <,LeFy\zW
ps.getIndexes()得到分页索引的数组 4=1lyw
ps.getTotalCount()得到总结果数 Vv zd>yII
ps.getStartIndex()当前分页索引 6H3_qx
ps.getNextIndex()下一页索引 z9VQsC'K
ps.getPreviousIndex()上一页索引 P{);$e+b~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 mNV4"lNR
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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 y{kXd1,
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一下代码重构了。 zO!`sPP
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我把原本我的做法也提供出来供大家讨论吧: |=7%Edkd
#'"h+[XY
首先,为了实现分页查询,我封装了一个Page类: 4h(aTbHaQ
java代码: >q]r)~8F^
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/*Created on 2005-4-14*/ *aTM3k)Zs
package org.flyware.util.page; >+8mq]8^
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/** dkCSqNFL)
* @author Joa 8_KXli}7=
* Va9vDb6
*/ E{j6OX\
publicclass Page { KnbP@!+c
4}8Xoywi1
/** imply if the page has previous page */ @UvjJ
privateboolean hasPrePage; bcOX/
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/** imply if the page has next page */ OY?uqP}c
privateboolean hasNextPage; pKp#4Js
L !{^^7
/** the number of every page */ J@1 (2%)|Z
privateint everyPage; 4,)=r3;&!
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/** the total page number */ W[YcYa_tQ
privateint totalPage; K_RrSI&>
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/** the number of current page */ 76c}Rk^
privateint currentPage; S~m*t i(
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/** the begin index of the records by the current /oWB7l&
p-ry{"XA
query */ &\1Dy}:
privateint beginIndex; M?]ObIM:5
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/** The default constructor */ 1)k))w 9
public Page(){ uE/qraA
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} rNI3_|a
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/** construct the page by everyPage !n
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* @param everyPage />]/At
* */ Ot v{#bB$
public Page(int everyPage){ 23Eg|Xk
this.everyPage = everyPage; >O~xu^N?
} :<nL9y jt
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/** The whole constructor */ eYS
public Page(boolean hasPrePage, boolean hasNextPage, 1no$|n#
@ '<lD*W
=. OWsFv
int everyPage, int totalPage, *r(iegO$
int currentPage, int beginIndex){ Oi7:J>
[
this.hasPrePage = hasPrePage; M8
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this.hasNextPage = hasNextPage; F2+lwyc Y
this.everyPage = everyPage; {'{ssCL
this.totalPage = totalPage; g%^Zq"
this.currentPage = currentPage; F[~qgS*;
this.beginIndex = beginIndex; #U!J2240
} [;};qQ-C2
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/** M~3(4,
* @return u*H2kn[DU
* Returns the beginIndex. `t#C0
*/ t+66kB N
publicint getBeginIndex(){ J&h 3,
return beginIndex; egKYlfe"
} 7rsrC
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/** hu6)GOZbv
* @param beginIndex |[xi"E\
* The beginIndex to set. _Z 9I')
*/ 8f#YUK
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publicvoid setBeginIndex(int beginIndex){ EMJ}tvL0Tp
this.beginIndex = beginIndex; nEs l
} Vd|/]Zj
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/** E6BW&Xp
* @return y:pypuwt;
* Returns the currentPage. 'O2{0
*/ ,P5HR+h
publicint getCurrentPage(){ yUBic~S
return currentPage; <sd
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} +}z
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/** =g?r.;OO
* @param currentPage <o
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* The currentPage to set. o1YhYA
*/ E-n!3RQ(w
publicvoid setCurrentPage(int currentPage){ l1!i3m'x
this.currentPage = currentPage; c-`&e-~XKL
} Br-bUoua
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/** hLO nX<%a
* @return VSM%<-iQ
* Returns the everyPage. |h8C}P&Z
*/
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publicint getEveryPage(){ |1rBK.8
return everyPage; 'gQm%:qU3r
} R?^FO:nM%!
uy 7)9w
/** iSHNt0Nl
* @param everyPage 2{ }5WH
* The everyPage to set. Ho*S>Y
*/ }|Cw]GW
publicvoid setEveryPage(int everyPage){ EYMwg_
this.everyPage = everyPage; A qE,zW
} Jtc?p{
h]G}E9\l
/** '(I"54W
* @return .LV=Z0ja
* Returns the hasNextPage. 7*u0)Hog
*/ }
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publicboolean getHasNextPage(){ 7Nx@eoZ
return hasNextPage; Vs m06Rj{
} bm(0raugs
3Qn! `
/** babDLaC@
* @param hasNextPage <@e6zQG
* The hasNextPage to set. ]+ug:E{7
*/ F;`es%8
publicvoid setHasNextPage(boolean hasNextPage){ trM8p
this.hasNextPage = hasNextPage; 3{~hRd
} nL@P{,J
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/** SlsMMD
* @return k&@JF@_TI
* Returns the hasPrePage. h&.9Q{D
*/ w QwY_ _
publicboolean getHasPrePage(){ N4'b]:`n
return hasPrePage; 67Ge}6*2pd
} hF!yp7l;
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/** EGU?54
* @param hasPrePage ?=f\oH$
* The hasPrePage to set. \fh.D/@
*/ sK}Ru?a)
publicvoid setHasPrePage(boolean hasPrePage){ %%klR{
this.hasPrePage = hasPrePage; c[J#Hc8;
} B8;_h#^q
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/** <)y'Ot0 y
* @return Returns the totalPage. z{;W$SO
2
* O:pQf/Xn
*/ nvgo6*
publicint getTotalPage(){ aD24)?db-
return totalPage; H~@aT7
} &UQKZ.
Pbd#Fu;
/** CM8WI~
* @param totalPage i8u9~F
* The totalPage to set. G8f7N;D
*/ rTW1'@E
publicvoid setTotalPage(int totalPage){ *slZ17xg
this.totalPage = totalPage; bAt!9uFn
} u;1#eP\;
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} R#
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 -&@[]/
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个PageUtil,负责对Page对象进行构造: CA[k$Sw*
java代码: q{n~s=
hTH"jAC+
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/*Created on 2005-4-14*/ k:`^KtBMl
package org.flyware.util.page; /8J2,8vZ
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import org.apache.commons.logging.Log; 9S.R%2xw`
import org.apache.commons.logging.LogFactory; kZSe#'R's
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/** ~F
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* @author Joa N~Ax78TX
* 4$SW~BpQ
*/ ]:m*7p\uk
publicclass PageUtil { w.^k':,"
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privatestaticfinal Log logger = LogFactory.getLog r 3pfG
>3 qy'lm
(PageUtil.class); ,Sghi&Ky
<$,iYx
/** 8t9sdqM/C
* Use the origin page to create a new page \`|,wLgH
* @param page &hjrJ/'^
* @param totalRecords ~sMn/T*fv
* @return VO. Y\8/
*/ Ya304Pjd
publicstatic Page createPage(Page page, int e[>(L% QV+
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totalRecords){ d=N5cCqq
return createPage(page.getEveryPage(), u&2uQ-T0
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page.getCurrentPage(), totalRecords); Hagj^8
} ?8YHz
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/** >d#B149
* the basic page utils not including exception 9FH=Jp
93[`1_q7\
handler o6Vc}jRH
* @param everyPage V@e0VV3yx%
* @param currentPage /rKrnxw
* @param totalRecords #^xiv/sV
* @return page ~wh8)rm
*/ ~)sb\o
publicstatic Page createPage(int everyPage, int WoesE:NiR
W53i5u(
currentPage, int totalRecords){ *kZJ
everyPage = getEveryPage(everyPage); ikyvst>O
currentPage = getCurrentPage(currentPage); *RN*Bh|$
int beginIndex = getBeginIndex(everyPage, P0}uTee
+% '0;
currentPage); g&riio7lx
int totalPage = getTotalPage(everyPage, RrKs!2sCT
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totalRecords); -%%2Pz0I
boolean hasNextPage = hasNextPage(currentPage, JcvK]x
gLd3,$Ei
totalPage); J=zh+oLCV
boolean hasPrePage = hasPrePage(currentPage); +#'exgGU^[
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returnnew Page(hasPrePage, hasNextPage, ;h0?o*i_
everyPage, totalPage, PNg, bcl
currentPage, GS<,adD
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beginIndex); ^J@Y?CQl\
} wR>\5z)^
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privatestaticint getEveryPage(int everyPage){ HO&#Lv
return everyPage == 0 ? 10 : everyPage; xxiEL2"`>
} 8~}Ti*Urc
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privatestaticint getCurrentPage(int currentPage){ {.Nt#l
return currentPage == 0 ? 1 : currentPage; w9i1ag
} t4F 1[P
B>|@XfPM
privatestaticint getBeginIndex(int everyPage, int \u",bMQF
6dq5f?w]
currentPage){ <@@.~Qm'
return(currentPage - 1) * everyPage; 83)2c a
} w9c
a2o+tR;H
privatestaticint getTotalPage(int everyPage, int U2@?!B[\d`
z`f1|Ok
totalRecords){ "m/0>UU0
int totalPage = 0; ,v>P05
=(.HO:#
if(totalRecords % everyPage == 0) 611:eLyy&l
totalPage = totalRecords / everyPage; bWjW_$8
else ,#D&*
totalPage = totalRecords / everyPage + 1 ; J"I{0>@
#LBZ%%v
return totalPage; !63x^# kg
} #}e)*(
;Fp"]z!Qh+
privatestaticboolean hasPrePage(int currentPage){ '.d el7s
return currentPage == 1 ? false : true; Y/)>\
} /d8PDc "
MP0gLi
privatestaticboolean hasNextPage(int currentPage, )P\ec
GP`_R
int totalPage){ '0/t |V<
return currentPage == totalPage || totalPage == NqlG= pu
DkQy.
0 ? false : true; pPeS4$Y
} F4Z+)'oDr,
o D:?fs]
hZc$`V=R
} xNE<$Bz
!XzRV?Ih;
%'k^aqFL
<Cn-MOoM
0alm/or
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。 p>65(&N,
>k
kuw?O@
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 RzFv``g
~qco -b
做法如下: R279=sO,J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 d,+d8X
W[w8@OCNf
的信息,和一个结果集List: 5A:b
\
java代码: 1Cp5a2{
oT%~)g
Pou`PNvH
/*Created on 2005-6-13*/ ]"{K5s7
package com.adt.bo; iS=}| 8"
4CfPa6_
import java.util.List; ZIkXy*<(
|V%Qp5 XJ
import org.flyware.util.page.Page; 6'+3""\
Y2QlK1.8V
/** l#V"14y
* @author Joa ~48Uch\LG:
*/ MU%C_d%.
publicclass Result { -~]*)&
qmv%N
private Page page; Da)9s %_4
YYZE-{ %
private List content; cZ%weQa#N)
=<n+AqJ%
/** *siS4RX2
* The default constructor (lTM^3
}
*/ 7`|$uIM`
public Result(){ s?7g3H5#0k
super(); f9X*bEl9;`
} yA
\C3r'
5e6]v2 k
/** IF$f^$
* The constructor using fields y]+i.8[
* \ C~Y
* @param page 50uNgLs
* @param content /i"L@t)\t
*/ ~t.*B& A
public Result(Page page, List content){ E@Q+[~H }
this.page = page; ^MKvZ DOP
this.content = content; x.xfMM2n
} 11Pm lzy
mJ)o-BV
/** j%#n}H
* @return Returns the content. <p-R{}8
*/ E+]gC
publicList getContent(){ Iyz} ;7yVI
return content; g75)&U`>}
}
TB1E1
Gt2NUGU
/** tTX2>8Gmr
* @return Returns the page. CES^
c-. k
*/ 7=aF-;X3jj
public Page getPage(){ S
XIo
return page; XjuAVNY
} [wj&.I{^s
5BN!uUkm+
/** ggzg,~V
* @param content hwSn?bkw
* The content to set. LIT{rR#8
*/ Gp6|M2Vu_5
public void setContent(List content){ b(wW;C'#0p
this.content = content; 9EIHcUXe
} ,mx>)}l95
^} %OqP
/** ))K3pKyb
* @param page
^uD r
* The page to set. /608P:U
*/ nNSq6 Cj
publicvoid setPage(Page page){ g0:mm,t\
this.page = page; 2bPrND\P=
} Ugp[Ugr
} Pe6MDWR
t5\~Z}G8
<w}YD @(f
MRMswNQ
E=_M=5]
2. 编写业务逻辑接口,并实现它(UserManager, Mm;kB/1
b*+Od8r
UserManagerImpl) /U4F\pZl
java代码: CE=&ZHt9
l&R~I6^E
5Q;Fwtm
/*Created on 2005-7-15*/ e23}'qb
package com.adt.service; Gc^w,n[E
NuRxk eEO
import net.sf.hibernate.HibernateException; 6FFQoE|n
KB0HM
import org.flyware.util.page.Page; O-[ lL"T
K?+iu|$&
import com.adt.bo.Result; *yN+Xm8o
s5_[[:c=^
/** (j@3=-%6 G
* @author Joa $!h21
*/ w] i&N1i
publicinterface UserManager { -aK_
9D#"Ey
public Result listUser(Page page)throws \dO9nwa?
u,mC`gz
HibernateException; >`R}ulz)
ebxpKtEC
} Q x}\[
>k)}R|tJ
P~HzNC
Q(=} PF
.Zv@iL5
java代码: `dO)}}| y
:Q@=;P2
FR"yGx#$
/*Created on 2005-7-15*/ fs_6`Xt
package com.adt.service.impl; gVO<W.?
8 h
import java.util.List; L 1iA
^x
FW~%xUSE5
import net.sf.hibernate.HibernateException; $9k7A 8K
f_2tMiy5
import org.flyware.util.page.Page; iOXxxP%#
import org.flyware.util.page.PageUtil; *{5p/}p
i P gewjx
import com.adt.bo.Result; JR>#PJ,N-
import com.adt.dao.UserDAO; \X1?,gV_
import com.adt.exception.ObjectNotFoundException; 6g06s @kz
import com.adt.service.UserManager; 7VQ|3`!<
\ <b-I
/** }i0(^"SoXZ
* @author Joa pxy=edd
*/ ' P5ttI#|
publicclass UserManagerImpl implements UserManager { zg L0v5vk
WsO'4~X9
private UserDAO userDAO; hUN]Lm6M
E_k<EQ%r
/** LE#ko2#ke
* @param userDAO The userDAO to set. &Z3g$R 9
*/ U\dq
Mp#Wy
publicvoid setUserDAO(UserDAO userDAO){ 30cZz
this.userDAO = userDAO; 6vy(@z
} U-!+Cxjs
Zt;3HY=y
/* (non-Javadoc) B'<k*9=Nv8
* @see com.adt.service.UserManager#listUser fP<Tvf
iG*@(
(org.flyware.util.page.Page) G>"=Af(t?Y
*/ ?XOl>IO
public Result listUser(Page page)throws 0*G
=~:
6?GR+;/
HibernateException, ObjectNotFoundException { |e49F
int totalRecords = userDAO.getUserCount(); u By[x 0
if(totalRecords == 0) \[u7y. b
throw new ObjectNotFoundException cXP*?N4Cf
t6m&+N
("userNotExist"); `P/7Mf
page = PageUtil.createPage(page, totalRecords); |Rk9W
List users = userDAO.getUserByPage(page); 9C9>V]
returnnew Result(page, users); 3Ov? kWFO
}
Ne>yFl"u
!Q(x A,p
} 6_xPk`m
JAEn
72
gT3i{iU
oTS/z\C"<u
KA^r,Iw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 phk fPvL{
W>[0u3
询,接下来编写UserDAO的代码: ;J<K/YdI
3. UserDAO 和 UserDAOImpl: [ H"\<"1o
java代码: mIk8hA@B_
k/'>,WE
l}\q }7\)
/*Created on 2005-7-15*/ J4Yu|E<&
package com.adt.dao; IXQxjqd^
]nmVT~lBe"
import java.util.List; =Rv!c+?
N`o[iHUj \
import org.flyware.util.page.Page; V+04X"
{DfXn1Cg0U
import net.sf.hibernate.HibernateException; FZdZGK
pCOtk'n
/** UqsJ44QEZ
* @author Joa :<Z>?x
*/ z#DgoA
publicinterface UserDAO extends BaseDAO { E(%_aFx>/
9:[L
WT&
publicList getUserByName(String name)throws j_w"HiNBA
i6Zsn#Z7)
HibernateException; cviPCjM
kF,_o/Jc
publicint getUserCount()throws HibernateException; 1^R[kaY
v2ab
publicList getUserByPage(Page page)throws YC,)t71l{
Wycood*
HibernateException; PRTn~!Z0
ePD~SO9*
} >s*ZT%TF
l:Hm|9UZ
.A6i?iROe
fm u;Pb]r
VDnN2)Km*
java代码: ,\".|m1o.
x~;1CB
E![Ye@w
/*Created on 2005-7-15*/ ^/`W0kT
package com.adt.dao.impl; G&7!3u
qHQWiu%h
import java.util.List; Dej_(Dz_S
0<^!<i(%
import org.flyware.util.page.Page; Ad%3 fvn
V1h&{D\"
import net.sf.hibernate.HibernateException; o$4xinK
import net.sf.hibernate.Query; )P|&o%E
P84uEDY
import com.adt.dao.UserDAO; *{K?JB#W
A3su!I2S
/** *PSUB{i(
* @author Joa _zuX6DO
*/ =eHoJq
public class UserDAOImpl extends BaseDAOHibernateImpl =PQMd
B)!ty"
implements UserDAO { \7\7i-Vo
{D>@ZC
/* (non-Javadoc) Ekl cnM|6
* @see com.adt.dao.UserDAO#getUserByName _{k-&I
n^xB_DJ~
(java.lang.String) wr`+xYuuC=
*/ kiP-^Wan
publicList getUserByName(String name)throws +xL*`fn
-%,3qhsd
HibernateException { O/{X:Ja{
String querySentence = "FROM user in class V]{^}AKc
,JU3w
com.adt.po.User WHERE user.name=:name"; Q"(*SA+-|
Query query = getSession().createQuery QGq8r>
O~udlVn<6
(querySentence); LtK= nK
query.setParameter("name", name);
gt>k]0
return query.list(); AuW-XK.
} O_S%PX
$yoIz.?V
/* (non-Javadoc) *ydh.R<hb
* @see com.adt.dao.UserDAO#getUserCount() 9CNeMoA$p:
*/ [t}@>@W|
publicint getUserCount()throws HibernateException { ]iq2_{q
int count = 0; J? 4E Hl
String querySentence = "SELECT count(*) FROM z&Kh$ $)[
6o
cTQ}=
user in class com.adt.po.User"; fvNj5Vq:
Query query = getSession().createQuery t(.jJ>|+*
J=`2{
'l
(querySentence); n@PXC8}
count = ((Integer)query.iterate().next UzKB "Q
&W*do
()).intValue(); *ujJpJZ2
return count; tupAU$h?!
} zu!#
<t"KNKI
/* (non-Javadoc) t4H*&U
* @see com.adt.dao.UserDAO#getUserByPage K2@],E?e%|
a)qlrtCl
(org.flyware.util.page.Page) &VdKL2
*/ h~r&7G@[}
publicList getUserByPage(Page page)throws jFH wu*
:={rPj-nU
HibernateException { yLY$1#Sa
String querySentence = "FROM user in class FE4P
EBXvu
]q":ta!f
com.adt.po.User"; sD{d8s[(
Query query = getSession().createQuery {;^GKb+
1> 'xmp+#
(querySentence); KGP *G
BZr
query.setFirstResult(page.getBeginIndex()) LKsK!X
.setMaxResults(page.getEveryPage()); mrGfu:r
return query.list(); >MLPmER
} D6vhW:t8?
w^=uq3X?
} M=t;t0
:\cid]y3
qbq.r&F&
>E\U$}WCG
"59"HVV
至此,一个完整的分页程序完成。前台的只需要调用 ]x1o (~
SFkB,)Z N
userManager.listUser(page)即可得到一个Page对象和结果集对象 $X ]t}=
uMb[0-5
的综合体,而传入的参数page对象则可以由前台传入,如果用 =EQaZ8k
rk7d7`V
webwork,甚至可以直接在配置文件中指定。 }Q-%ij2
^tRy6zG
下面给出一个webwork调用示例: l",X
java代码: 16|miK[@
o!Y61S(
xWxgv;Ah
/*Created on 2005-6-17*/ Rl[SqmnI)@
package com.adt.action.user; kR]AW60OE
)tp;2rJ/
import java.util.List; {D`_q|
s#4Q?<65u
import org.apache.commons.logging.Log; Rd|M)
import org.apache.commons.logging.LogFactory; ,wB)hp
import org.flyware.util.page.Page; V[^+lR
)F3>
import com.adt.bo.Result; /?B%,$~
import com.adt.service.UserService; 01">$
import com.opensymphony.xwork.Action; w1:%P36H
z:W|GDD1
/** Nf1&UgX
* @author Joa 7$A=|/'nSA
*/ txFcV
publicclass ListUser implementsAction{ SS7C|*-Zd
1pJ?YV
privatestaticfinal Log logger = LogFactory.getLog m.&"D>
\t
$LHF=tYS
(ListUser.class); IcUE=J
jUCDf-_ m
private UserService userService; (AswV7aGe
>fx/TSql:J
private Page page; UdK +,k~m/
@jT=SFf
privateList users; %R@&8
C sx
EN4
/* x>[f+Tc
* (non-Javadoc) N51WY7
* m4 :"c"
* @see com.opensymphony.xwork.Action#execute() @X]JMicJ
*/ [5wU0~>'
publicString execute()throwsException{ g<s;uRA4O9
Result result = userService.listUser(page); _GsHT\
page = result.getPage(); =0mXTY1
users = result.getContent(); TF-a1z
return SUCCESS; bw*D!mm,
} 7da~+(yhr
)g[7XB/w
/** G[s/M\l
* @return Returns the page. ?7Skk
*/ t[%ELHV
public Page getPage(){ :Nl.< 6+
return page; 0uhIJc'2
} C)|#z/"
jOU1F1
/** Na{&aqdz
* @return Returns the users. Hg`2-
Nl
*/ p0@l581
publicList getUsers(){ 0&2eiMKG?n
return users; PLs(+>H
} Ct pc]lJ}
u#`'|ko\9
/** z[*Y%o8-r
* @param page #}aBRKZf6
* The page to set. ^_XV }&7Q
*/ QI{<q<
publicvoid setPage(Page page){ _[8sL^
this.page = page; @2R+?2 j
} 4KZ)`KPE
&8@
a"
/** c%x.cbu>
* @param users Ufv0Xj
* The users to set. (qg~l@rf
*/ u%rB]a$/
publicvoid setUsers(List users){ S<nbNSu6+
this.users = users; ah|`),o(k
} X:d[eAu0
Qm2(Z8Gh
/** <hzuPi@
* @param userService A]AM|2 D
* The userService to set. ^5~)m6=2
*/ 9Lqo^+0)\
publicvoid setUserService(UserService userService){ n%I9l]
this.userService = userService; ~PiCA
} ?PDrj/: *
} &ZAc3@l[c
"MU)8$d
.8/W_iC92
O`FuXB(t
AW/)R"+
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, "7_qB8\
%a$Fsn
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 'QxPQcU
n8 e4`-cY
么只需要: .9KW|(uW
java代码: Nj|~3
*KO
]-tAgNzl%
5 @61=Au
<?xml version="1.0"?> hSfLNvK
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork jS'hs>Ot
P<s:dH"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]WZi +
\X0wr%I
1.0.dtd"> ;P2(C >|
<]kifiN#
<xwork> ;+4X<)y*>
?KtvXTy{m
<package name="user" extends="webwork- <nE |Y@S
<n|.Z-gF\
interceptors"> Q5pm^X._j
jN^09T49
<!-- The default interceptor stack name ~[9(}UM
70{fl
4J5
--> |,OTGZgc
<default-interceptor-ref AlQ
B(U0 ~{7a
name="myDefaultWebStack"/> }Q%fY(bp
8I|2yvhP
<action name="listUser" |q*s)8
)uIHonXU
class="com.adt.action.user.ListUser"> 8et.A
<param TLiA>`r=
B#9T6|2
name="page.everyPage">10</param> +yYSp8>
<result (y{nD~k
_=68iDXm
name="success">/user/user_list.jsp</result> L}5IX)#gH
</action> ht@s!5\LK
'c|Y*2@
</package> H-Z1i
HnmByn\j
</xwork> XG_Iq ,
UONW3}-
7]6HXR @
A1nEp0%Y
PM!7ci
sT"h)I)]*
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 {ei,>5K
C>*]a(5k
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。 (Jb[_d*
8ncgTCH:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %l8nTcL_?
$>mTPNF
8GD!]t#
{|Pz9a-:
fG\]&LFBU
我写的一个用于分页的类,用了泛型了,hoho hV4\#K[
Mb0cdK?hA
java代码: lj o^ 2
xr\wOQ*`
@YfCS8
eH
package com.intokr.util; Cq, hzi-
>4} 2~;
import java.util.List; C5jR||
)wwQv2E
/** X[
o9^<
* 用于分页的类<br> "x$RTuWA9
* 可以用于传递查询的结果也可以用于传送查询的参数<br> KGI0|Z]n~
* 1@Zjv>jy[
* @version 0.01 wh<s#q`
* @author cheng ]
x_WO_
*/ Aa;s.:?
public class Paginator<E> { 32*FI SH^
privateint count = 0; // 总记录数 'ehJr/0&g
privateint p = 1; // 页编号 ,3{z_Rax-
privateint num = 20; // 每页的记录数 n/3gx4.g
privateList<E> results = null; // 结果 %Pb 5PIk4
*R6n+d
/** (mJqI)m8
* 结果总数 2W=(
{e)$
*/ 6:Nz=sw8
publicint getCount(){ cn4CK.?
return count; G;%Pf9o26
} 6T_Mk0Sf+
buhn~ c
publicvoid setCount(int count){ g(0
|p6R
this.count = count; $LF
}
Bjz\L0d
K"sfN~@rT[
/** KR6*)?c`
* 本结果所在的页码,从1开始 NgnHo\)
* *L9s7RR
* @return Returns the pageNo. T$'GFA
*/ L:y}
L
publicint getP(){ syYg, G[
return p; Hop$w
} <4W"ne28
AE)<ee%\\
/** 2>l:: 8Pp
* if(p<=0) p=1 !$>d75zli
* Aghcjy|j
* @param p `1NxS35u
*/ F%Lniv/N
publicvoid setP(int p){ Ha\q}~_
if(p <= 0) !j)H!|R
p = 1; lq$1CI
this.p = p; gq6C6
} [Pdm1]":(
b-{\manH
/** )-9G*3
* 每页记录数量 KsGS s9
*/ VX<ZB +R
publicint getNum(){ b+NF:-fO
return num; v?yH j-
} b\%=mN
OH28H),}
/** &DFe+y~PR
* if(num<1) num=1 $;_'5`xs
*/ S#X$QD
publicvoid setNum(int num){ 2oAPJUPOJ
if(num < 1) ^b`}g
num = 1; x, js}Mlw
this.num = num; >qjr7 vx
} $.}fL;BzVz
ih?_ fW
/** +0=u]
* 获得总页数 EvMhNq~y5
*/ w.cQ|_
publicint getPageNum(){ vL13~q*F
return(count - 1) / num + 1; }}?L'Vby
} A>$VkGo
i_ 4FxC4
/** r6Z&i^cMe
* 获得本页的开始编号,为 (p-1)*num+1 }(-R`.e;
*/ ^\cB&<h
publicint getStart(){ r +;C}[E
return(p - 1) * num + 1; jz|zq\Eek
} \qAMs^1-
y'Xg"
/** O!zH5
* @return Returns the results. e+=Oj o#
*/ kRskeMr:Rd
publicList<E> getResults(){ qqSk*oH~
return results; T IPb ]
} ASAz<H$
d'Z|+lq:
public void setResults(List<E> results){ Z\xR+3
this.results = results;
Nora<
} /MSz{ %v
{t[j>_MYw
public String toString(){ A$W,#`E
StringBuilder buff = new StringBuilder !a3cEzs3
]}F_nc2L
(); Tn/
3`j
{
buff.append("{"); K3?7Hndf2
buff.append("count:").append(count); QQ97BP7W
buff.append(",p:").append(p); Qg?^%O'
buff.append(",nump:").append(num); E'$r#k:o
buff.append(",results:").append #HB]qa
!l_1r$
(results); _p7c<$;
buff.append("}"); p[&'*"o!/
return buff.toString(); IQdiVj
} D<}KTyG]
oj@B'j
} Gw3|"14
Te2XQU2,F
ZSYXUFz