Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 & F\HR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s ki'I
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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 6O uB}*
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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 b7 %Z~
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分页支持类: h3U| ~h
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java代码: LldZ"%P
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{
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package com.javaeye.common.util; KPc`5X
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import java.util.List; R"%zmA@o=
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publicclass PaginationSupport { x{y}pH "H
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; cCOw7<
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privateList items; &/)2P#u
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privateint totalCount; ;$=kfj9 :7
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privateint[] indexes = newint[0]; pK/r{/>r
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privateint startIndex = 0; X+6`]]
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public PaginationSupport(List items, int y~eQVnH5W
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totalCount){ BJA&{DMHm
setPageSize(PAGESIZE); =zaf{0c
setTotalCount(totalCount); Wgp}v93
setItems(items); VS.~gHx
setStartIndex(0); +r8:t5:/I
} P D,s,A
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public PaginationSupport(List items, int 7ns n8WN[
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totalCount, int startIndex){ pf&H !-M
setPageSize(PAGESIZE); ]{sx#|_S
setTotalCount(totalCount); R9+0ZoS
setItems(items); K;uO<{a)r
setStartIndex(startIndex); jg)+]r/hS
} [Q0n-b,Q
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ R%%Uw %`
setPageSize(pageSize); kD}w5 U
setTotalCount(totalCount); nr*nX
setItems(items); !!KA9mP
setStartIndex(startIndex); V=
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} e^ Aw%t
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publicList getItems(){ ^Kbq.4
return items; K$1(HbL
} ^pc?oDPSg
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publicvoid setItems(List items){ A r=P;6J
this.items = items; s*;rt
} 6x*$/1'M3;
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publicint getPageSize(){ uge~*S
return pageSize; f)_k_ <
} Kb$6a'u7
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publicvoid setPageSize(int pageSize){ Vb57B.I
this.pageSize = pageSize; 6&,{"N0T
} h 2QJQ|7a
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publicint getTotalCount(){ nSSj&q- O
return totalCount; lWyg_YO@
} QAxR'.d
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publicvoid setTotalCount(int totalCount){ Can:!48
if(totalCount > 0){ HKXtS>7d
this.totalCount = totalCount; #TG7WF5
int count = totalCount / #qcF2&a%
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pageSize; ZUd*[\F~!
if(totalCount % pageSize > 0) A+QOox]<
count++; Ib}~Q@?2
indexes = newint[count]; .-mlV ^
for(int i = 0; i < count; i++){ eZbT;
indexes = pageSize * By;{Y[@rS
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i; zI&).
} 95IR.Qfn!
}else{ rvUJK,oE
this.totalCount = 0; ?l?_8y/ww
} 4_KRH1
} Fo;.
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publicint[] getIndexes(){ m`!Vryf
return indexes; 8b|m6 6#|
} s~b!3l`gu
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publicvoid setIndexes(int[] indexes){ yyv<MSU8
this.indexes = indexes; '{F
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} ~&7 *<`7{
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publicint getStartIndex(){ SrT=XX,
return startIndex; V }wh
} p9Y`_g`
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publicvoid setStartIndex(int startIndex){ +9NI=s6
if(totalCount <= 0) R-]i BL
this.startIndex = 0; _s~F/G`iT
elseif(startIndex >= totalCount) +*=?0 \
this.startIndex = indexes dz"HO!9
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[indexes.length - 1]; 5X}OUn8
elseif(startIndex < 0) &m~
this.startIndex = 0; d$<1Ma}
else{ ,/Yo1@U
this.startIndex = indexes )%Lgo${[;
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[startIndex / pageSize]; FX&)~)
} p}MH LM
} e)Pm{:E
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publicint getNextIndex(){ J?[}h&otQ
int nextIndex = getStartIndex() + G&,2>qxKR
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pageSize; W't.e0L<6
if(nextIndex >= totalCount) IEQ6J}L
return getStartIndex(); 12 S[m~L%
else &Tn7
return nextIndex; 40Z/;,wp{
} *rmwTD"
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publicint getPreviousIndex(){ tg%C>O
int previousIndex = getStartIndex() - nTH!_S>b(Y
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pageSize; Yvxp(
if(previousIndex < 0) -) \!@n0
return0; !k0t
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else fS- 31<?
return previousIndex; zmpQ=%/H
} SX6P>:`
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} QP[`*X
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抽象业务类 90]{4 ]y;
java代码: ealh>Y
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/** <#5`%sa '
* Created on 2005-7-12 hP]zC1s
*/ %{K6
package com.javaeye.common.business; &Vi0.o
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import java.io.Serializable; }hX"A!0
import java.util.List; t.tdY
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import org.hibernate.Criteria; MESPfS+
import org.hibernate.HibernateException; aShZdeC*f
import org.hibernate.Session; i4*!t.eI
import org.hibernate.criterion.DetachedCriteria; o]@g%_3X
import org.hibernate.criterion.Projections; m8ydX6~max
import lITZ|u
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org.springframework.orm.hibernate3.HibernateCallback; (!&g (l;
import wJF Fg :
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org.springframework.orm.hibernate3.support.HibernateDaoS D$[/|%3
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upport; M"$TXXe
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import com.javaeye.common.util.PaginationSupport; dk9nhS+faJ
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public abstract class AbstractManager extends t?j2Rw3f`I
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HibernateDaoSupport { BA+:}81&<q
p; ZEz<M
privateboolean cacheQueries = false; Q|W!m0XO
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privateString queryCacheRegion; JI}p{yI
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publicvoid setCacheQueries(boolean ]0wmvTR
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cacheQueries){ &Jw4^ob
this.cacheQueries = cacheQueries; lt&30nf=
} P$|DiiH
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publicvoid setQueryCacheRegion(String (B zf~#]~
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queryCacheRegion){ 7F{=bL
this.queryCacheRegion = WsCzC_'j.
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queryCacheRegion; +6*
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} AH(O"v`
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publicvoid save(finalObject entity){ .iL_3:6f
getHibernateTemplate().save(entity);
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} x{|n>3l`b9
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publicvoid persist(finalObject entity){ 7TQh'j
getHibernateTemplate().save(entity); S hM}w/4
} ;,h*s,i
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publicvoid update(finalObject entity){ ptmPO4f
getHibernateTemplate().update(entity); Ueyt}44.e2
} Q nqU!6k@
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publicvoid delete(finalObject entity){ =`X;fz
getHibernateTemplate().delete(entity); )LYj,do
} ab 1\nzpd
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publicObject load(finalClass entity, : |c,.uO
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finalSerializable id){ cF[[_
return getHibernateTemplate().load B|O/h!H.
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(entity, id); qpl "j-
} ~j\/3;^s
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publicObject get(finalClass entity, lC1X9Op
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finalSerializable id){ GfQP@R"
return getHibernateTemplate().get /j'We-C
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(entity, id); z~oGd,
} Ac.z6]p
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publicList findAll(finalClass entity){ uBks#Y*3$
return getHibernateTemplate().find("from ^tuJM:
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" + entity.getName()); {Pg7IYjH
} V]PTAhc
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publicList findByNamedQuery(finalString pKMf#)qm
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namedQuery){ *k'9 %'<
return getHibernateTemplate j86s[Dty
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().findByNamedQuery(namedQuery); =I/J !}.
} ZF;S}1
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publicList findByNamedQuery(finalString query, |U^
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finalObject parameter){ 5Kv=;o=U
return getHibernateTemplate wrn[q{dX
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().findByNamedQuery(query, parameter); _'AIXez7q
} V_}`2.Pg
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publicList findByNamedQuery(finalString query, l:HO|Mq
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finalObject[] parameters){ D2!ww{t
return getHibernateTemplate <$D)uY K
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().findByNamedQuery(query, parameters); 3Uag[ms
} 6XQ)Q)
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publicList find(finalString query){ h)wR[N]n
return getHibernateTemplate().find ~:)$~g7>b
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(query); O:7y-r0i
} 6g$04C3tHi
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publicList find(finalString query, finalObject z7P PwTBa
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parameter){ T"d]QYJS
return getHibernateTemplate().find il-&d]AP
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(query, parameter); LwGcy1F.
} x2ol
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public PaginationSupport findPageByCriteria J*U(f{Q(
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(final DetachedCriteria detachedCriteria){ g>im2AD+e
return findPageByCriteria ^1cqx]>E
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); m'qMcCE
} ^m1Rw|
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public PaginationSupport findPageByCriteria c>UITM=!I
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(final DetachedCriteria detachedCriteria, finalint C}1(@$
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startIndex){ ,Fr{i1Ky
return findPageByCriteria -~(0:@o ;
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(detachedCriteria, PaginationSupport.PAGESIZE, x:2[E-
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startIndex); Nl@Hx
} t'Q48QAb?
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public PaginationSupport findPageByCriteria IeU.T@ $
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(final DetachedCriteria detachedCriteria, finalint `a6;*r y
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pageSize, 95!xTf
finalint startIndex){ "Z{^i3gN
return(PaginationSupport) {9l4 pT3
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getHibernateTemplate().execute(new HibernateCallback(){ T]vD ,I+
publicObject doInHibernate '[-/Xa['
ttw@nv%
@
(Session session)throws HibernateException { _?r+SRFn
Criteria criteria = ;:!LAe
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detachedCriteria.getExecutableCriteria(session); u\E.H5u27
int totalCount = 16Xwtn72
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((Integer) criteria.setProjection(Projections.rowCount 1OGlD+f
NfO0^^"
()).uniqueResult()).intValue(); uyA9`~p=#
criteria.setProjection #* Hhe>
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(null); p5H Mg\hT
List items = *"4<&F
S
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criteria.setFirstResult(startIndex).setMaxResults SUVr&S6Nk
& aLR'*]6
(pageSize).list(); OKU P
PaginationSupport ps = SA&wW\Ym]
n)=&=Uj`f
new PaginationSupport(items, totalCount, pageSize, \ D[BRE+
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startIndex); 16+@#d%#p
return ps; K7l{&2>?
} AHA*yC
}, true); .6"7Xxe]<
} an7N<-?
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public List findAllByCriteria(final @E)XT\;3
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DetachedCriteria detachedCriteria){ PT4`1Oy}/1
return(List) getHibernateTemplate Qpc{7#bp
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().execute(new HibernateCallback(){ lxd<^R3i#^
publicObject doInHibernate }"8_$VDcz
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(Session session)throws HibernateException { bCrB'&^t
Criteria criteria = 5cADC`q
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detachedCriteria.getExecutableCriteria(session); u<8Q[_E&
return criteria.list(); &qU[wn:1
} :U*[s$
}, true); fr?eOigbl
} 'I~dJEW7
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public int getCountByCriteria(final 5R Hs
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DetachedCriteria detachedCriteria){ f
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Integer count = (Integer) Vg+SXq6G
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getHibernateTemplate().execute(new HibernateCallback(){ lV
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publicObject doInHibernate CL*%06QyE
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(Session session)throws HibernateException { |l|]Tw
Criteria criteria = 3q>"#+R.t
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detachedCriteria.getExecutableCriteria(session); NLpD,q{
return G#V22Wca8
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criteria.setProjection(Projections.rowCount P2p^jm
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()).uniqueResult(); %FU[j^
} ?MYD}`Cv
}, true); la4,Z
return count.intValue(); HA%ye"(y8
} YZ>cE#
} g)9/z
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用户在web层构造查询条件detachedCriteria,和可选的 ]| yH8 m
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w(j9[
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PaginationSupport的实例ps。 hvyN8We
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ps.getItems()得到已分页好的结果集 {dwV-qz
ps.getIndexes()得到分页索引的数组 q T].,?
ps.getTotalCount()得到总结果数 `9+EhP$RS
ps.getStartIndex()当前分页索引 3EvA 5K.
ps.getNextIndex()下一页索引 #+;=ijyF
ps.getPreviousIndex()上一页索引 _D9=-^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }'W^Ki$
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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 qM0MSwvC=
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一下代码重构了。 ECScx02
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我把原本我的做法也提供出来供大家讨论吧: EVFfXv^
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首先,为了实现分页查询,我封装了一个Page类: u-_$?'l;~
java代码: k)p y\
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/*Created on 2005-4-14*/ pL@zZK0
package org.flyware.util.page; m_2P{
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/**
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* @author Joa Q*.FUV&;
* /aG>we
*/ Q/c
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publicclass Page { Lf#G?]@
_6!/}Fm
/** imply if the page has previous page */ aS vE
privateboolean hasPrePage; (NdgF+'=
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/** imply if the page has next page */ <6C9R>
privateboolean hasNextPage; 4C%>/*%8>
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/** the number of every page */ w<Cmzkf
privateint everyPage; \&5@ yh
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/** the total page number */ dV{Hn {(
privateint totalPage; DA$Q-
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/** the number of current page */ rfRo*u2"
privateint currentPage; N[bN"'U/1
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/** the begin index of the records by the current rR@n>
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query */ $
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privateint beginIndex; <IyLLQ+v
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/** The default constructor */ d7J[.^\
public Page(){ q7&yb.<KD.
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} .)>/!|i
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/** construct the page by everyPage {(}w4.!
* @param everyPage =t$mbI
* */ SU
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public Page(int everyPage){ D?}m
h1#
this.everyPage = everyPage; yvWzc
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} 0DB<hpC:5
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/** The whole constructor */ |Xm4(FN\
public Page(boolean hasPrePage, boolean hasNextPage, ;"Y;l=9_
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int everyPage, int totalPage, d Zz^9:C+
int currentPage, int beginIndex){ 9/daRq$
this.hasPrePage = hasPrePage; hcd>A vC8
this.hasNextPage = hasNextPage; (1SO;8k\
this.everyPage = everyPage; yp{F8V 8
this.totalPage = totalPage; UD<^r]'x
this.currentPage = currentPage; v?D
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this.beginIndex = beginIndex; W(a'^
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} 62)lf2$1
QP5:M!O<)
/** m0\"C-Bk
* @return n5k^v$'
* Returns the beginIndex. }gi1?a59
*/ "gN* J)!x
publicint getBeginIndex(){ R%N#G<^R
return beginIndex; V> a3V'
} +%}5{lu_e
B N*,!fx
/** 3cfZ!E~^kc
* @param beginIndex CESe}^)n
* The beginIndex to set. Wytvs*\`
*/ EkStb#
publicvoid setBeginIndex(int beginIndex){ 3]`qnSYBv
this.beginIndex = beginIndex; !|<f%UO
} *K jVPs
pmW6~%}*
/** _X%6 +0M
* @return H"FflmUO
* Returns the currentPage. ( X
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*/ B`Or#G3ph
publicint getCurrentPage(){ 1s}``1>
return currentPage; =!S@tuY
} ADyNNMcx
Tt <-<oyU.
/** (#-=y~%
* @param currentPage /[|}rqX(
* The currentPage to set. GATP
*/ )|Vg/S
publicvoid setCurrentPage(int currentPage){ b*FU*)<4.
this.currentPage = currentPage; Ife,h
s
} [Yx-l;78
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/** v[,v{5b
* @return R5NRCI
* Returns the everyPage. 7<R6T9g
*/ C*{15!d:G
publicint getEveryPage(){ HV*:<2P%D
return everyPage; vN0L(B
} a(x.{}uG,
}uvKE|umj
/** U|
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* @param everyPage 0K$WSGB?6j
* The everyPage to set. UYcyk
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*/ 2yJ7]+Jd7Y
publicvoid setEveryPage(int everyPage){ KtfkE\KP
this.everyPage = everyPage; q-3J.VLJ5H
} G {pP}
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/** 'TK$ndy;7}
* @return KM_)7?`
* Returns the hasNextPage. [al(>Wr9
*/ C NzSBm
publicboolean getHasNextPage(){ cy&
return hasNextPage; (}*\ {
} F;?TR[4!k
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/** Lt;.Nw
* @param hasNextPage ~4=]%XYz
* The hasNextPage to set. ,<;l"v(
*/ K4?t' dd]
publicvoid setHasNextPage(boolean hasNextPage){ :\1rQT
this.hasNextPage = hasNextPage; 2\nBqCxR
} uGP[l`f|FQ
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/** Ypn%[sSOp
* @return 8g#
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* Returns the hasPrePage. c6?c>*z
*/ F;d%@E_Bc
publicboolean getHasPrePage(){ .`p<hA)%[C
return hasPrePage; CzzUi]*Ac{
} w|
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c]%;^)
/** VeNNsg>&
* @param hasPrePage %S
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* The hasPrePage to set. r6oX6.c
*/ uGuc._}=
publicvoid setHasPrePage(boolean hasPrePage){ Yn IM-
this.hasPrePage = hasPrePage; ~>N`<S
} mc0sdb,c$
3ZW/$KP/
/** tf$PaA
* @return Returns the totalPage. 12:h49AP
* Y91
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*/ `zElBD
publicint getTotalPage(){ @b::6n/u
return totalPage; OQytgXED
} Edf=?K+\!i
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/** XI%RneuDr:
* @param totalPage q7O,I`KaJ
* The totalPage to set. 0%h[0jGj
*/ ; d, JN
publicvoid setTotalPage(int totalPage){ KA|&Q<<{@
this.totalPage = totalPage; 27Kc-rcB
} |MOn0*
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} $n=W2WJ6f
U,%s;
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 dJdD"xj
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个PageUtil,负责对Page对象进行构造: {+@ms$z
java代码: QmWC2$b
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AI^AK0.L
/*Created on 2005-4-14*/ oTq%wi6 _
package org.flyware.util.page; ILkjz^
}
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import org.apache.commons.logging.Log; ')AByD}Hi]
import org.apache.commons.logging.LogFactory; _%A/ )
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/** 8_^'(]
* @author Joa -vv
* $:%*gY4~76
*/ iN:G/ss4O
publicclass PageUtil { ^Ei*M0fF
jHkyF`<+
privatestaticfinal Log logger = LogFactory.getLog VRtbHam
%-h7Z3YcN
(PageUtil.class); x\Nhix}1D
D 7Gd%
/** f0-RhR
* Use the origin page to create a new page &_Cxv8
* @param page paq8L{R
* @param totalRecords ;el]LnV!O
* @return 5S&aI{;9<
*/ q
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publicstatic Page createPage(Page page, int L]c 8d
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totalRecords){ lSZ"y
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return createPage(page.getEveryPage(), +
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page.getCurrentPage(), totalRecords); )HJK '@
} + 6x"trC
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/** >[Xm|A#
* the basic page utils not including exception 2.StG(Y!
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handler Q;XXgX#l
* @param everyPage 3mpP|b"
* @param currentPage {M`
* @param totalRecords L\QQjI{
* @return page 3M}AxE u
*/ '4J&Gp x
publicstatic Page createPage(int everyPage, int 8pXfT%]
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currentPage, int totalRecords){ umJay/>
everyPage = getEveryPage(everyPage); M.o?CX'
currentPage = getCurrentPage(currentPage); rER~P\-
int beginIndex = getBeginIndex(everyPage, f2uZK!:m
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currentPage); fdd~e52f
int totalPage = getTotalPage(everyPage, NY~ dM\
"F&Tnhh4
totalRecords); LTg?5GwD\j
boolean hasNextPage = hasNextPage(currentPage, \ua9thOG
kFS0i%Sr
totalPage); j FgZ}Xp
boolean hasPrePage = hasPrePage(currentPage); 9U!JK3d
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returnnew Page(hasPrePage, hasNextPage, s ;48v
everyPage, totalPage, eA`]KalH
currentPage, u=(H#o<#
t@X M /=d
beginIndex); 3wV86tH%
} }j&O/Up
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privatestaticint getEveryPage(int everyPage){ n(Qj||:
return everyPage == 0 ? 10 : everyPage; ,yTN$K%M
} K3La9O)>
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privatestaticint getCurrentPage(int currentPage){ Xfj)gPt}
return currentPage == 0 ? 1 : currentPage; kBrvl^D{5
} `2pO5B50
jeY4yM
privatestaticint getBeginIndex(int everyPage, int FL59
RwUW;hU
currentPage){ Vz%"9`r
return(currentPage - 1) * everyPage; 72`/d`
} ymHKcQ
bAUHUPe
privatestaticint getTotalPage(int everyPage, int oz Vpfs
*^n^nnCwp
totalRecords){ :RPVT,O}
int totalPage = 0; ZmNZS0j
4"LPJX)Q
if(totalRecords % everyPage == 0) baqn7k"
totalPage = totalRecords / everyPage; SO7(K5H,
else fv:L\N1u
totalPage = totalRecords / everyPage + 1 ; 3)dP7rmZ
sc<kiL
return totalPage; A8J?A#R*{q
} ',DeP>'%>
o\d |CE;>
privatestaticboolean hasPrePage(int currentPage){ TV?
^c?{5
return currentPage == 1 ? false : true; n:F@gZd`
} #U\$@4D
t/ A:k
privatestaticboolean hasNextPage(int currentPage, Pv#KmSA9
6s'[{Ov
int totalPage){ VZ;@S3TS
return currentPage == totalPage || totalPage == O)l%OOv
%j%%Rn
0 ? false : true; 6{L F-`S%
} V!mWn|lf
d"Bo8`_
.Xi2G@D
} T)`gm{T
#uB[&GG}W
Yi[4DfA
.a {QA
H%FM
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。 ^Wf
S\M`
g/x_m.
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 }&mj.hGv
{798=pC<.
做法如下: AYt*'Zeg!s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]Uu
aN8
b"^\)|*4;
的信息,和一个结果集List: Xp#~N_S$
java代码: /GyEV Cc
o94PI*.
D$ ej+s7
/*Created on 2005-6-13*/ OqtQA#uL
package com.adt.bo; )q^(T1
0Qt~K#mr/
import java.util.List; ,b$z!dvhl
Ac
J>$L)
import org.flyware.util.page.Page; 1p~5h(jI
)mj<{Td`
/** l4zw]AYk+X
* @author Joa ,eDu$8J9
*/ <H!O:Mf_p
publicclass Result { ~bWhth2*
A3j"/eKi2
private Page page; !1("(Eb
@Zj&`/
private List content; HXyFj
Q@3B{
/** _g65pxt =Z
* The default constructor &u("|O)w$
*/ sLNNcj(Cy>
public Result(){ Y4`QK+~fH
super(); V>AS%lXj
} JfSdUWxT
{b[tA,
>
/** hw*1g m
* The constructor using fields
C[R`Ml
* +eC3?B8rN
* @param page @bE~@4mOu
* @param content 3Qa?\C&4
*/ 8+&gp$a$
public Result(Page page, List content){ 2!BsEvB(
this.page = page; 6oYIQ'hc
this.content = content; pG~'shD~Dn
} .ByU
b22LT52
/** $Vsy%gA<
* @return Returns the content. 9?$RO[vo
*/ x`#22"m
publicList getContent(){ BK*z 4m
return content; moaodmt]x
} Wy8,<K{
1c/
X
/** K|Om5
p
* @return Returns the page. tR5tPPw
*/ K\~v&
public Page getPage(){ ^:+Rg}]W^
return page; zPHy2H$28
} 2Sjt=LOc="
">cqt>2 A
/** V\"1wV~E
* @param content .8:+MW/
* The content to set. M.S
s:ttj
*/ svqvG7
public void setContent(List content){ Vli3>K&
this.content = content; -(
(Z@T1k
} TH YVT%v
@"w2R$o
/** v[smQO
* @param page VE*j*U
j
* The page to set. _!%M%
*/ (U _wp's
publicvoid setPage(Page page){ qv$!\ T
this.page = page; 1g~y]iQ
} A*R n<{U
} o _(0
Ox~ 9_d
l0. FiO@_Q
#3.\j"b
z(rK^RT
2. 编写业务逻辑接口,并实现它(UserManager, h07eEg
RT/qcS^Oz
UserManagerImpl) t{6ap +%L
java代码: e$32
;$z7[+M
'u1=XX
h
/*Created on 2005-7-15*/ ~GA8_B
package com.adt.service; &kiF/F 1
>K5~:mx#3
import net.sf.hibernate.HibernateException; w2C&%Xk
Y+@g~TE
import org.flyware.util.page.Page; )@_ugW-j
|_, /u_
import com.adt.bo.Result; YNk|+A.<d
Ch7Egzl7?
/** i%MA"I\9
* @author Joa ` zY!`G
*/ DRp&IP<
publicinterface UserManager { F3Ap1-%z
OT;cfkf7
public Result listUser(Page page)throws -zTEL(r
BJgDo
HibernateException; Xo8DEr
<}]{~y
} C38%H
iE=P'"I
ewym1}o
eG4>d^`c
rFfy#e
java代码: D'nL
?&xlT+JM
K#wK1 Sv
/*Created on 2005-7-15*/ 5j`v`[B;
package com.adt.service.impl; Yg&`
U^7]B
rnH}#u+
import java.util.List; rH.gF43O:
6rT4iC3Q{
import net.sf.hibernate.HibernateException; _Z.cMYN
{-h, ZdH^
import org.flyware.util.page.Page; fnWsm4
import org.flyware.util.page.PageUtil; S/fW/W*/}
CL1
oAk
import com.adt.bo.Result; [%?y( q
import com.adt.dao.UserDAO; 2uL9.q
import com.adt.exception.ObjectNotFoundException; c.0]1
import com.adt.service.UserManager; F"[3c6yF
ABZ06S/
/** hiN/S|JN8y
* @author Joa lV)G@l[1
*/ NpR6
publicclass UserManagerImpl implements UserManager { 3nrqo<X
%Hwbw],kl8
private UserDAO userDAO; "wINBya'M
L+t[&1cW
/** S>#R_H<(
* @param userDAO The userDAO to set. s1=+::
*/ . ,R4WA,
publicvoid setUserDAO(UserDAO userDAO){ m8HYWzN
this.userDAO = userDAO; A9;0y jae
} -dG,*0 >
;'^, ,{
/* (non-Javadoc) )2V@ p~k?
* @see com.adt.service.UserManager#listUser iadkH]w
Z2bUs!0
(org.flyware.util.page.Page) R8 jovr
*/ v?)SA];
public Result listUser(Page page)throws r[!(?%>j
uREu2T2
HibernateException, ObjectNotFoundException { aq kix"J
int totalRecords = userDAO.getUserCount(); K:_($X]
if(totalRecords == 0) 0+j}};
throw new ObjectNotFoundException fGTOIi@#
HY*\ k#
("userNotExist"); V7@
{D
page = PageUtil.createPage(page, totalRecords); bE4HDq34
List users = userDAO.getUserByPage(page); AerFgQiS
returnnew Result(page, users); 0D~=SekQ9
} ZF'HM@cfo
3Oiy)f@{TF
} 11{y}J
!^L-T?y.2
8&."uEOOU
Dft%ip2
uw"*zBxl
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 k!owl+a
;{Jb6'K1h
询,接下来编写UserDAO的代码: ^mf jn-=3
3. UserDAO 和 UserDAOImpl: U0IE1_R
java代码: u(2BQO7
w~LU\Ct
y<*-tZV[
/*Created on 2005-7-15*/ n| C|&
package com.adt.dao; no|Gq>Xp
|[LE9Lq/
import java.util.List; jyQVSQs
K(OaW)j
import org.flyware.util.page.Page; Y 1y E
l#xw.2bo
import net.sf.hibernate.HibernateException;
g`3H(PVg
}N]!0Ka
/** g_M^E-3
* @author Joa ~6HDW
*/ e8q4O|I_
publicinterface UserDAO extends BaseDAO { >3P9 i ;W
Noz&noq
publicList getUserByName(String name)throws }NwN2xTB
"@)lH
HibernateException; ?d5h9}B
3+9
U1:1[.
publicint getUserCount()throws HibernateException; q~h:<,5
WK4@:k
m6)
publicList getUserByPage(Page page)throws ^*>n4U
-)RJ\V^{9
HibernateException; ]]/lC
xiCN
qk3
} c,$mWTC
@ef$b?wg
wko2M[
4m /TW)
[gZDQcU
java代码: k%Eh{dA
i| 4_m
xYwkFB$$*
/*Created on 2005-7-15*/ `xIh\q
package com.adt.dao.impl; S&01SX6
`Cg ^in\
import java.util.List; !tBeuemN%
r<|nwFJ
import org.flyware.util.page.Page; NjP ]My
:o$@F-$k
import net.sf.hibernate.HibernateException; t'aSF{%
import net.sf.hibernate.Query; "kr,x3
=
vgo{]:Aj{
import com.adt.dao.UserDAO; Mz\yPT;Y
PG"@A
/** =ybGb7?
* @author Joa zX~}]?|9
*/ )S Q('vwg
public class UserDAOImpl extends BaseDAOHibernateImpl H%C\Uz"o
yQwVQUW8B
implements UserDAO { waQtr,m)
PkJcd->
/* (non-Javadoc) ?l9=$'
* @see com.adt.dao.UserDAO#getUserByName u-39r^`5
3agNB F2
(java.lang.String) : I)G v
*/ !.X_/$c
publicList getUserByName(String name)throws @'gl~J7
:t5uDKZ_j)
HibernateException { 7}o6_i
String querySentence = "FROM user in class EzpwGNfz }
!qaDn.9
com.adt.po.User WHERE user.name=:name"; {+\'bIV[
Query query = getSession().createQuery /{R3@,D[]
{XHk6w
*-
(querySentence); $m8leuo)
query.setParameter("name", name); O#G|
~'.,
return query.list(); lR}%)3_k
} h?A'H RyL~
T3rn+BxF 7
/* (non-Javadoc) k9&@(G[K3
* @see com.adt.dao.UserDAO#getUserCount() xE1rxPuq)d
*/ k(v"B@0
publicint getUserCount()throws HibernateException { uS-3\$
int count = 0; 6F-JK1i
String querySentence = "SELECT count(*) FROM eJ:Yj
~X`<
NQR^%<hU
user in class com.adt.po.User"; OAVQ`ek
Query query = getSession().createQuery oAnigu;
K7Gm-=%
(querySentence); }9=2g`2Q
count = ((Integer)query.iterate().next F"=Hp4-C
zp#:EZ
()).intValue(); B.6`cM^
return count; phS>T
} BkV(81"C
jN {Zw*
/* (non-Javadoc) Qg> 0G%cXU
* @see com.adt.dao.UserDAO#getUserByPage ]?&H^"=
_NT[
~M_Q
(org.flyware.util.page.Page) ALAL( f`
*/ 6g|#ho1Bbs
publicList getUserByPage(Page page)throws pw;r 25
f8#*mQ
HibernateException { $`v+4]
String querySentence = "FROM user in class 1ys( v
O4N-_Kfp/
com.adt.po.User"; y7La_FPrl
Query query = getSession().createQuery
Wxs>osq
ArL-rJ{}
(querySentence); V4EM5 Z\k
query.setFirstResult(page.getBeginIndex()) E\iJP^n
.setMaxResults(page.getEveryPage()); tIp{},bQ^
return query.list(); <N-=fad]
} QXB|!'
[9HYO
} 117c,yM0
8H_l[/
$W*|~}F/Ap
F"v:}Vy|
9M]^l,
至此,一个完整的分页程序完成。前台的只需要调用 c"qPTjY
w49{-Pp[
userManager.listUser(page)即可得到一个Page对象和结果集对象 /4-}k
{=6)SBjf
的综合体,而传入的参数page对象则可以由前台传入,如果用 x,f>X;04
Mlwdha0
webwork,甚至可以直接在配置文件中指定。 !3?yG
+0dT^Jkqg
下面给出一个webwork调用示例: j9>TTgy@
java代码: wB2}uk7
=+4 _j
Hh@2 m\HA
/*Created on 2005-6-17*/ "4RQ`.SR
package com.adt.action.user; }>,CUz
zu C5@jy.x
import java.util.List; 2md.S$V$,
PK}vh%
import org.apache.commons.logging.Log; MISE C[/
import org.apache.commons.logging.LogFactory; 'QnW9EHLF
import org.flyware.util.page.Page; |e+aZ%g
CdNih8uG
import com.adt.bo.Result; ^6#-yDZC@
import com.adt.service.UserService; . wmkj
import com.opensymphony.xwork.Action; jNIUsM8e
/L$NE$D} "
/** r*]uR /Z$
* @author Joa 8
#Fh>
*/ vU{jda$$#
publicclass ListUser implementsAction{ p&uCp7]U
a-:pJE.'p
privatestaticfinal Log logger = LogFactory.getLog 716hpj#*
@'Q%Jc(
(ListUser.class); e lay
=%)
9ClF<5?M
private UserService userService; 4M7^
[G
pW7kj&a_.
private Page page; G\):2Qz!|
(Wn
"3
]
privateList users; l<Lz{)OR
LC76 Qi;|k
/* ho_4fDv
* (non-Javadoc) smbUu/
* k0knPDbHv
* @see com.opensymphony.xwork.Action#execute() (qbc;gBy
*/ @~hz_Nm@8
publicString execute()throwsException{ Q84t9b
Result result = userService.listUser(page); ;!:F#gahv
page = result.getPage(); )6g&v'dq
users = result.getContent(); [*tU}9
return SUCCESS; ,.h$&QFj;
} 1MpX] j8C#
VD9J}bgJ
/** 1P \up
* @return Returns the page. l%@dE7<Z
*/ 4[Z1r~t\L
public Page getPage(){ QY@nE
return page; j $KM9
} "s${!A)
7fUi?41XA
/** gn364U a
* @return Returns the users. XA?WUR[e
*/ dbg|VoNf
publicList getUsers(){ tgc@7
return users; [1mIdwS
} bIq-1
Y(
<jg8y'm@0
/** z}D#WWSxf
* @param page @|Z*f\
* The page to set. yTP[,bM
*/ D)h["z|F
publicvoid setPage(Page page){ 8dlInms
this.page = page; aK!xRnY
} +B](5 z4
"\}21B~{7'
/** ^971<B(v
* @param users
KzIt
* The users to set. UQSX<6"
*/ yB|]LYh
publicvoid setUsers(List users){ +A&EKk%$ |
this.users = users; P&h/IBA_
} ~T;K-9R
X4XFu
/** e
W9)@nVJ
* @param userService GCZu<,
* The userService to set. t;oT {Hge
*/ )Gx":
D
publicvoid setUserService(UserService userService){ 9&&kgKKGQ
this.userService = userService; m)(SG
} Vvx a.B
} 'T6B_9GQ8
Feh"!k <6k
~>.awu+o|
neK*jdaP
5c*p2:]
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, r*c82}tc
9UB??049z
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 2&suo!ig
{_": /A
么只需要: XryQ)x(
java代码: @"jmI&hYn
nl.~^CP
S$Ns8=
<?xml version="1.0"?> 9@kcK
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ](]*]a4ss
;L#LDk{Za
1.0//EN" "http://www.opensymphony.com/xwork/xwork- zojuH8
XB6N[E
1.0.dtd"> Ym3
"
_-g-'Hr+N
<xwork> D>psh-,1
V<
2IIH5^
<package name="user" extends="webwork- |TC3*Y
V]+o)A$
interceptors"> mjWp8i
g%@]z8L
<!-- The default interceptor stack name fQ2!sV
i!s~kk
--> f0:EQYYZ
<default-interceptor-ref v=dKcruR:
U`?zC~
name="myDefaultWebStack"/> o'9OPoof:.
m$j
n5:
<action name="listUser" eA3`]XP.`b
]C9%]`
class="com.adt.action.user.ListUser"> <K|3Q'(S
<param ex0
kb
oHYD_8'f
name="page.everyPage">10</param> 6R3"L]J
<result %4QoF
CpBQ>!CW
name="success">/user/user_list.jsp</result> ~}hba3&b;#
</action> ~{52JeUc P
!gD 3CA
</package> '8]|E
&!H~bzg
</xwork> g~bf!
BH.:_Qrbh[
I,?Fqg'sq
9n06n$F
l}U~I
3}).
[)C)p*!Y)
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 c,b`N0dOKL
c,g]0S?gu
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。 ,3fuX~g
WHhR)$zC
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 E.5*Jr=J
4\ uZKv@,
<lg"M;&Ht
t?3{s\z 8+
muqfSF
我写的一个用于分页的类,用了泛型了,hoho N3S,33
8s
. }-@;:yh
java代码: M]%!n3Fb
PV Q#>_~5
b#/V;
package com.intokr.util; 0+VncL)u
1@1+4P0NF[
import java.util.List; U|y;b+n`
~/]\iOL
/** GlV-}5W
* 用于分页的类<br> ;%b <uV
* 可以用于传递查询的结果也可以用于传送查询的参数<br> \'}/&PCkr
* jL>I5f
* @version 0.01 N9>'/jgZX
* @author cheng Jq$6$A,f
*/ q;Ar&VrlNq
public class Paginator<E> { s)`1Rf
privateint count = 0; // 总记录数 g4.'T51
privateint p = 1; // 页编号 {Q#Fen
;y|
privateint num = 20; // 每页的记录数 iuH8g
privateList<E> results = null; // 结果 qxg7cj2
7 ~%
/** Uy_}@50"l
* 结果总数 LB64W ;#h
*/ W?4&lC^G
publicint getCount(){ /
%U~lr
return count; TQbFI;\
} 2yCd:wg
5Xy^I^J
publicvoid setCount(int count){ K{r1&O>W
this.count = count; dwf #~7h_
} l9ch
%0y3 /W
/** 0Tn|Q9R
* 本结果所在的页码,从1开始 ,h5-rw'
* JQ{zWJlt
* @return Returns the pageNo. 2y
.-4?e
*/ hq&
publicint getP(){ j
44bF/
return p; nIN%<3U2
} YiQeI|{oN
0.{oA`5N
/** FRJ:ym=E
* if(p<=0) p=1 #P,[fgNy
* cQ8$,fo
* @param p fjK]m.w
*/ f@xfb
ie!
publicvoid setP(int p){ 1>*UbV<R;u
if(p <= 0) 0[$Mo3c+'
p = 1; DbNi;m
this.p = p; J*q=C%}.
} nV,{w4t+
R1b
)
/** tr9_bl&z
* 每页记录数量 '@}?NV0
*/ -$]DO5fY
publicint getNum(){ +(h6{e%)
return num; I vl^,{4
} LPm# 3U
.xc/2:m9
/** 1l`s1C
* if(num<1) num=1 J9$]]\52s.
*/ ~jRk10T(B
publicvoid setNum(int num){ UV
*tO15i
if(num < 1) xjn8)C
num = 1; zN8V~M;
this.num = num; %]:vT&M
} ^?S@v1~7d
>I66R;
/** pg& ]F
* 获得总页数 wor'=byh\
*/ *l'$pJ X
publicint getPageNum(){ /cg]wG!n8
return(count - 1) / num + 1; $et
:
} @,>=X:7
~|B!.+
/** S1^Mw;?P
* 获得本页的开始编号,为 (p-1)*num+1 R82Zr@_
*/ *O}'2Ht6\
publicint getStart(){ =R24h
return(p - 1) * num + 1; [k&s!Qp
} c:,{O0 #
V.a]IkK'K
/** VOF:+o@.
* @return Returns the results. YQ8x6AJ
*/ (!&O4C5
publicList<E> getResults(){ XX5(/#
return results; +n.j.JP"X
} 4[V6so 0
*d,n2a#n5
public void setResults(List<E> results){ ADl>~3b
this.results = results; F~@1n,[
} 6x3Ew2
OD@A+"
public String toString(){ O@(.ei*HJ!
StringBuilder buff = new StringBuilder }${ZI
ALt";8Oa
(); ~\s &]L
buff.append("{"); .2 SIU4[P
buff.append("count:").append(count); XJ1nhE
buff.append(",p:").append(p); [j+0EVwB
buff.append(",nump:").append(num); wqoN@d
buff.append(",results:").append I:>d@e/;
]O(HZD%
(results); S?z j&XY3
buff.append("}"); q@"4Rbu6
return buff.toString(); "YvBb:Z>
} GC#95
S0QU@e
} &I'F-F;
xfV2/A#h
xXh]z|