Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 O<ybiPR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4dm0:,
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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 IfT: 9
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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 p 16+(m
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分页支持类: UFC^lv
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java代码: 'ka$@,s :
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package com.javaeye.common.util; H7k@Br
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import java.util.List; ZAn9A>5_
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publicclass PaginationSupport { J#q^CWN3R
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publicfinalstaticint PAGESIZE = 30; YQWq*o^:
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privateint pageSize = PAGESIZE; @sW!g;\T
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privateList items; <;uM/vSi
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privateint totalCount; A-J#$B
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privateint[] indexes = newint[0]; )."dqq^ q
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privateint startIndex = 0; kB%.i%9\\
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public PaginationSupport(List items, int gf>GK/^HH
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totalCount){ @=
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setPageSize(PAGESIZE); $*LBZcL
setTotalCount(totalCount); sZ7~AJ
setItems(items); j)#yyK{k2s
setStartIndex(0); 7j29wvSp5
} 6urU[t1
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public PaginationSupport(List items, int E25w^x2
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totalCount, int startIndex){ )o-mM
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setPageSize(PAGESIZE); 1Dhu5ht
setTotalCount(totalCount); (_6JQn
setItems(items); RKM5FXX
setStartIndex(startIndex); 3(nnN[?N,5
} JT=ax/%Mo
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public PaginationSupport(List items, int l|iOdKr h
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totalCount, int pageSize, int startIndex){ 2E`mbT,v&
setPageSize(pageSize); =''b `T$
setTotalCount(totalCount); {oR@'^N
setItems(items); `M(st%@n
setStartIndex(startIndex); !w@i,zqu
} h%NM%;"H/
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publicList getItems(){ t;-F]
return items; X[f)0w%
} c-!3wvt)
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publicvoid setItems(List items){ ^SW9J^9
this.items = items; N2Ysi$
} MJCz %zK
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publicint getPageSize(){ uu"hu||0_
return pageSize; k@h0 }%
} |sl^4'Ghc
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publicvoid setPageSize(int pageSize){ bI_MF/r''
this.pageSize = pageSize; @; I9e
} 9\T9pjdZE
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publicint getTotalCount(){ ^dsj1#3z
return totalCount; ^zS;/%
} Bu+?N%CBi
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publicvoid setTotalCount(int totalCount){ O:
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if(totalCount > 0){
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this.totalCount = totalCount; lV$#>2Hh5
int count = totalCount / ckv8QAm
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pageSize; ^4Ff8Y
if(totalCount % pageSize > 0) x8~*+ j
count++; k g Rys
indexes = newint[count]; i[ws%GfEv
for(int i = 0; i < count; i++){ j)Kd'Va
indexes = pageSize * [1ClZ~f
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i; X#K;(.},h
} 45$aq~%as
}else{ q)KOI`A
this.totalCount = 0; {MTtj4$
} &-X51O C
} x5Fo?E
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publicint[] getIndexes(){ e@ $|xa")
return indexes; oA7| s1
} h@\HPYi#.
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publicvoid setIndexes(int[] indexes){ U~t!
this.indexes = indexes; ,?Zy4-
} 53pT{2]zAi
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publicint getStartIndex(){ 79-50}A
return startIndex; x;-D}#
} }UQ,B
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publicvoid setStartIndex(int startIndex){ j]]5&u/l
if(totalCount <= 0) qDhZC*"9#D
this.startIndex = 0; X8?@Y@
elseif(startIndex >= totalCount) AZA5>Y
this.startIndex = indexes @$
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[indexes.length - 1]; Dhfor+Epy
elseif(startIndex < 0) \pTv;(
this.startIndex = 0; {XUSw8W'
else{ kBk2mMZ
this.startIndex = indexes oDJ
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[startIndex / pageSize]; mFxt +\
} H~SU:B:
} ?4Fev_5m
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publicint getNextIndex(){ apgKC;
int nextIndex = getStartIndex() + Wm5[+z|2?9
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pageSize; *M0O&" ~j
if(nextIndex >= totalCount) m({q<&]Qp
return getStartIndex(); q;IuV&B
else C dPQhv)m
return nextIndex; D%c^j9' 1
} UQ7La 7"
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publicint getPreviousIndex(){ E|SmvIV-
int previousIndex = getStartIndex() - \Y!=O=za]
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pageSize; NYs<`6P:Y
if(previousIndex < 0) o{n#f?EA
return0; B,%KvL&xMX
else OL:hNbw'~T
return previousIndex; !?Y71:_!
} {4f%UnSz(
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} es\
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抽象业务类 -vk/z+-^!
java代码: ,# .12Q!
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/** 6c/0OM#
* Created on 2005-7-12 qe(C>qjMbG
*/ Aw4)=-LKO
package com.javaeye.common.business; ,!g/1m
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import java.io.Serializable; 1&7?f
import java.util.List; O:RN4/17
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import org.hibernate.Criteria; 589fr"Ma,6
import org.hibernate.HibernateException; j
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import org.hibernate.Session; Zy:q)'D=
import org.hibernate.criterion.DetachedCriteria; K V?+9qa,
import org.hibernate.criterion.Projections; @Gw]cm
import h^`@%g9 S
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org.springframework.orm.hibernate3.HibernateCallback; kApD D[ N
import /Dt:4{aTOC
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org.springframework.orm.hibernate3.support.HibernateDaoS T?=]&9Y'
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upport; uk,9N
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import com.javaeye.common.util.PaginationSupport; F{.g05^y
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public abstract class AbstractManager extends I69Z'}+qz
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HibernateDaoSupport { O*,O]Q
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privateboolean cacheQueries = false; H$Pf$D$
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privateString queryCacheRegion; 2e3AmR@*
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publicvoid setCacheQueries(boolean D(dV{^} 9
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cacheQueries){ :J2^Y4l2
this.cacheQueries = cacheQueries; IDh`*F
} &G\C[L
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publicvoid setQueryCacheRegion(String ]6|?H6'/`v
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queryCacheRegion){ ,nP nH1vb
this.queryCacheRegion = n-qle5s j
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queryCacheRegion; -y?ve od#
} )-}<}< oO
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publicvoid save(finalObject entity){ 6Rq +=X
getHibernateTemplate().save(entity); yOb']
} mRGr+m
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publicvoid persist(finalObject entity){ :fy,%su
getHibernateTemplate().save(entity); _z.CV<
} s*i,Ph
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publicvoid update(finalObject entity){ Tkp"mT
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getHibernateTemplate().update(entity); 4mX]JH`UTe
} L5 Ai
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publicvoid delete(finalObject entity){ fLSDt(c',
getHibernateTemplate().delete(entity); d& v 7l
} J<Ki;_=I
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publicObject load(finalClass entity, h2:TbQ
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finalSerializable id){ np}0OX
return getHibernateTemplate().load ?hIDyM
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(entity, id); <dBz]W
} vQ$"|8,
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publicObject get(finalClass entity, =i7CF3
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finalSerializable id){ Nr]guC? rE
return getHibernateTemplate().get [=Nv=d<[p
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(entity, id); 7/Bj WU5*
} iF.f*3-NJB
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publicList findAll(finalClass entity){ /!/Pk'p=/
return getHibernateTemplate().find("from \lDh"
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" + entity.getName()); I,&
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} d$?+>t/
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publicList findByNamedQuery(finalString BI!E mA
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namedQuery){ N"~P$B1X
return getHibernateTemplate r(n>N0:0Ls
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().findByNamedQuery(namedQuery); k>!i
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} pB%oFWqK
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publicList findByNamedQuery(finalString query, jgkY^l
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finalObject parameter){ mfDt_Iq
return getHibernateTemplate *Id[6Z
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().findByNamedQuery(query, parameter); ~rAcT6#
} V^}$f3\B
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publicList findByNamedQuery(finalString query, ~ySsv
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finalObject[] parameters){ j``Ku@/x0
return getHibernateTemplate ~Q]::
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().findByNamedQuery(query, parameters); o{mVXidE
} #D>:'ezm
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publicList find(finalString query){ F6h IG G
return getHibernateTemplate().find [w+1<ou;j
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(query); ,k9.1kjO*)
} i?mUQ'H
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publicList find(finalString query, finalObject UvqnNA
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parameter){ E2S#REB4
return getHibernateTemplate().find F2)KAIl
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(query, parameter); %\!0*(8
} 2%H_%Zu9
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public PaginationSupport findPageByCriteria sY]pszjT
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(final DetachedCriteria detachedCriteria){ Sj8fo^K50
return findPageByCriteria aan(69=jz
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5,Co(K
} jz\>VYi(7
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public PaginationSupport findPageByCriteria plNw>rFa
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(final DetachedCriteria detachedCriteria, finalint {?3i^Q=V
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startIndex){ N7;kWQH
return findPageByCriteria rQPO+
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(detachedCriteria, PaginationSupport.PAGESIZE, '68#7Hs.
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startIndex); ;L%\[H>G
} =xb/zu(
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public PaginationSupport findPageByCriteria |]Y6*uEX<
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(final DetachedCriteria detachedCriteria, finalint RE]*fRe7#
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pageSize, p DU+(A4>
finalint startIndex){ {L M Q
return(PaginationSupport) ,}Im^~5
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getHibernateTemplate().execute(new HibernateCallback(){ /c7jL4oD
publicObject doInHibernate (^<skx>
=#&+w[4?&.
(Session session)throws HibernateException { N)KN!!
Criteria criteria = kn&BGYt
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detachedCriteria.getExecutableCriteria(session); Qv8 =CnuOT
int totalCount = W{ZJ^QAq/
)E6E}
((Integer) criteria.setProjection(Projections.rowCount ^Q!A4qOQ
&u(pBr8B
()).uniqueResult()).intValue(); 8Qkwg]X
criteria.setProjection OY!WEP$F-C
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(null); F C=N}5u
List items = 9*r l7
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criteria.setFirstResult(startIndex).setMaxResults I.%EYAai
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(pageSize).list(); 8N4E~*>C
PaginationSupport ps = 3i9~'j;F3
jgfr_"@A
new PaginationSupport(items, totalCount, pageSize, e&Z ?I2J
A3.pz6iT>
startIndex); 1h{7dLA
return ps; 5/HkhTyj
} (/i|3 P
}, true); RgzzbW
} e
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public List findAllByCriteria(final P|;f>*^Y
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DetachedCriteria detachedCriteria){ 5`::#[
return(List) getHibernateTemplate }=u#,nDl>$
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().execute(new HibernateCallback(){ ')(U<5y)
publicObject doInHibernate bPuO~#iN~
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(Session session)throws HibernateException { Zk31|dL
Criteria criteria = 1I8<6pi-
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detachedCriteria.getExecutableCriteria(session); q'uGB fE.
return criteria.list(); LO38}w<k
} Y&$puiH-j
}, true); x l=i_
} &Cr4<V6-q
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public int getCountByCriteria(final _k(&<1i
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DetachedCriteria detachedCriteria){ >g{b'Xx
Integer count = (Integer) p>W@h*[6w
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getHibernateTemplate().execute(new HibernateCallback(){ LQ||7>{eX
publicObject doInHibernate gYmO4/c,
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(Session session)throws HibernateException { KfQR(e9n
Criteria criteria = $JiypX^DOP
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detachedCriteria.getExecutableCriteria(session);
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return 8,&Y\b`..
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criteria.setProjection(Projections.rowCount O! _d5r&,
KNOVb=#f_
()).uniqueResult(); *lQa^F
} pxW*kS
}, true); 9A9T'g)Du
return count.intValue(); &/g^J\ 0M)
} Ss\FSEN!/
} bP4}a!t+n
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用户在web层构造查询条件detachedCriteria,和可选的 ff00s+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _SU6Bd/>
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PaginationSupport的实例ps。 uhB
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ps.getItems()得到已分页好的结果集 `X<a(5[vV3
ps.getIndexes()得到分页索引的数组 M6].V *k'2
ps.getTotalCount()得到总结果数 .s KfwcYu4
ps.getStartIndex()当前分页索引 Jw{duM;]
ps.getNextIndex()下一页索引 #RHt;SFx
ps.getPreviousIndex()上一页索引 6r`Xi&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 `O0y8
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 "|V}[ 2
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一下代码重构了。 be?Bf^O>
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我把原本我的做法也提供出来供大家讨论吧: uJ0Wb$%
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首先,为了实现分页查询,我封装了一个Page类: flOXV
java代码: R]0`-_T
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/*Created on 2005-4-14*/ $KlaZ>Dh
package org.flyware.util.page; {@k
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/** [8K :ml
* @author Joa Sf@xP.d
* d qO]2d
*/ F@zTz54t
publicclass Page { Oz)/KZ
lr@w1*
/** imply if the page has previous page */ W{~ y< `D
privateboolean hasPrePage; s^Xs*T@~h
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/** imply if the page has next page */ po.QM/b
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privateboolean hasNextPage; D]N)
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/** the number of every page */ U} w@,6
privateint everyPage; s_e*jM1
mc{W\H
/** the total page number */ *vq75k$7
privateint totalPage; 7zIfsb
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/** the number of current page */ y9w,Su2
privateint currentPage; }w8yYI
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/** the begin index of the records by the current N>1d]DrQR
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query */ 1/K1e$r
privateint beginIndex; 2<:dA >1
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/** The default constructor */ #rNc+
public Page(){ UT[{NltH
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} ;'
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/** construct the page by everyPage S\!vDtD@
* @param everyPage ]q4(%Q
* */ VE}r'MBk
public Page(int everyPage){ r3KNRr@
this.everyPage = everyPage; ai;Q,Vy
} #&1gVkvp
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/** The whole constructor */ Q{an[9To~P
public Page(boolean hasPrePage, boolean hasNextPage, T8x8TN"
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int everyPage, int totalPage, g:GywXW
int currentPage, int beginIndex){ ZSyXzop
this.hasPrePage = hasPrePage; |f!J-H)
this.hasNextPage = hasNextPage; &0fV;%N
this.everyPage = everyPage; &xGpbJG
this.totalPage = totalPage; #M5d,%?+#[
this.currentPage = currentPage; 5?([jAOf
this.beginIndex = beginIndex; H4j1yD(d
} #9~,d<H
5% }!z~8Y4
/** `(=?k[48
* @return 5UG9&:zu'V
* Returns the beginIndex. ]lqZ9rO
*/ gsl_aW!
publicint getBeginIndex(){ ;%^{Zybh
return beginIndex; !hHX8TD^J
} 0,Ib74N'w
.yFO]
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/** DbX7?Jr
* @param beginIndex ]yL+lv
* The beginIndex to set. ;jN1n
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*/ md!!$+a%|
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; LsaX
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} :8==Bu
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/** 5SmJ'zFO
* @return *ZFF$0}
* Returns the currentPage. J9DI(`
*/ H)EL0
Kv/
publicint getCurrentPage(){ GIn%yB'
return currentPage; {2q0Ko<
} 8eYEi
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/** +
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* @param currentPage 7J
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* The currentPage to set. B([-GpZt[
*/ 'J5F+,\Ka
publicvoid setCurrentPage(int currentPage){ AO|1m$xf
this.currentPage = currentPage; ^u1Nbo
} 8#- Nx]VM
uXLZ!LJo
/** %e3E}m>
* @return V0W4M%
* Returns the everyPage. V\opC6*L_e
*/ DS>&|zF5l
publicint getEveryPage(){ vqO#Z
return everyPage; ;Bj&9DZd
} a1/+C$
oB
k;2.g$)W[c
/** \8s:I+[HH
* @param everyPage pV;0Hcy
* The everyPage to set. w-xigm>{Z
*/ Cc,V ]
publicvoid setEveryPage(int everyPage){ kE8s])Z,+
this.everyPage = everyPage; 3EY
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} =5V7212
MI^$df
/** JYA>Q&
* @return 4z26a
* Returns the hasNextPage. CR%h$+dzy
*/ $Bl51VjN
publicboolean getHasNextPage(){ UnYb}rF#%
return hasNextPage; O>a1S*mxP
} ccPWfy_
jm@M"b'{
/** D!/ 4u0m
* @param hasNextPage /h.{g0Xc
* The hasNextPage to set. xpo^\E?2
*/ -1d*zySL
publicvoid setHasNextPage(boolean hasNextPage){ hsS&|7Pt
this.hasNextPage = hasNextPage; N:k>V4oE
} tcsb]/my
gsM^Pu09ud
/** |G$-5
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* @return sPeTW*HeR
* Returns the hasPrePage. Ip=QtNW3\
*/ LL)t)
publicboolean getHasPrePage(){ %"fO^KA.h]
return hasPrePage; q5-i=lw
} @xa$two
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/** !G0Mg; ,
* @param hasPrePage VwZ~ntk
* The hasPrePage to set. ;in-)`UC!
*/ :yJ([
publicvoid setHasPrePage(boolean hasPrePage){ ^_DwuY
this.hasPrePage = hasPrePage; Zv=pS
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} $x]/|u/9
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/** CI-za !T
* @return Returns the totalPage. [u2t1^#Ol
* {=mGXd`x?l
*/ {6:*c
publicint getTotalPage(){ s@7h oU-+
return totalPage; X;GU#8W
} 4;CI<&S
alHA&YC{K
/** 3W_7xLA
* @param totalPage cSV&p|
* The totalPage to set. uL1lB@G@
*/ K<`Z@f3'w
publicvoid setTotalPage(int totalPage){ l"nS+z
this.totalPage = totalPage; 3o?eUwI}
} 'VCuMCV
z},\1^[
} Ddg!1SF
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1E&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 r hucBm
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个PageUtil,负责对Page对象进行构造: $ B&ZnZ?
java代码: EA8plQ~GtE
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/*Created on 2005-4-14*/ !bYVLFp=\_
package org.flyware.util.page; Ry]9n.y
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import org.apache.commons.logging.Log; #G F.M,O/h
import org.apache.commons.logging.LogFactory; 0 D
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/** bEQ- ?X%7
* @author Joa Xo~q}(ze^
* 0+@:f^3]!
*/ ZCc23UwI
publicclass PageUtil { 6Z J-oT!.
7kE+9HmfMk
privatestaticfinal Log logger = LogFactory.getLog S\A0gOL^
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(PageUtil.class); m[3c,Axl7
83/m^^F{]
/** _u$DcA8B
* Use the origin page to create a new page "B
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* @param page &;P\e
* @param totalRecords u^{p'a'
* @return js <Up/1
*/ @_-,Q5
publicstatic Page createPage(Page page, int >Jx=k"Kv+
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totalRecords){ ,&S0/j
return createPage(page.getEveryPage(), vn$=be8l4
W$NFk(
page.getCurrentPage(), totalRecords); Aixe?A_x
} Q. O4R_H
(Q%
@]
/** *P`wuXn}
* the basic page utils not including exception :" !Z9l\@
*#Ia8^z=p
handler ;)CN=J!
* @param everyPage 1@t.J>
* @param currentPage ki@C}T5
* @param totalRecords H8? Y{H
* @return page xp95KxHHo
*/ S!=R\_{u$
publicstatic Page createPage(int everyPage, int IBJNs$
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currentPage, int totalRecords){ DH+kp$,}
everyPage = getEveryPage(everyPage); zs
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currentPage = getCurrentPage(currentPage); }Cw,m0KV/
int beginIndex = getBeginIndex(everyPage, f*Q9u >1p
i^.eX
VV/
currentPage); `Tyd1!~
int totalPage = getTotalPage(everyPage, nTr]NBR
M3@qhEf?vk
totalRecords); s<!G2~T
boolean hasNextPage = hasNextPage(currentPage, w[gt9]}N
a7ZufB/
totalPage); sZ&|omN
boolean hasPrePage = hasPrePage(currentPage); S8/~'<out
JP6 Noia
returnnew Page(hasPrePage, hasNextPage, A~a 3bCX+"
everyPage, totalPage, mKO~`Wq%@
currentPage, U.t][#<3
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beginIndex); !Ea! "}
} -;_"Y]#
AJ*17w
privatestaticint getEveryPage(int everyPage){ SIrNZ^I
return everyPage == 0 ? 10 : everyPage; 16 `M=R
} |au`ph5
2 >O [Y1
privatestaticint getCurrentPage(int currentPage){ X0P +[.i
return currentPage == 0 ? 1 : currentPage; MT>(d*0s
} 6X h7Bx1
,Owk;MV@
privatestaticint getBeginIndex(int everyPage, int O H2IO
BX[IWP\%
currentPage){ 1%B9xLq
return(currentPage - 1) * everyPage; N}B&(dJ
} #9DJk,SP
hui
#<2{
privatestaticint getTotalPage(int everyPage, int n)q8y0if
0:[A4S`X
totalRecords){ L
QV@]z&
int totalPage = 0; ,(x`zpp _
}>BNdm"Er
if(totalRecords % everyPage == 0) Bj\
x
totalPage = totalRecords / everyPage; ~"`e9Im
else hjg1By(
totalPage = totalRecords / everyPage + 1 ; .p e3L7g
Q34u>VkdQI
return totalPage; ^lV}![do!
} V>)/z|[
MSM8wYcD
privatestaticboolean hasPrePage(int currentPage){ B;=Z^$%T
return currentPage == 1 ? false : true; }a5TY("d9H
} *'8q?R?7g
dNt^lx
privatestaticboolean hasNextPage(int currentPage, vkGF_aenk
|wuTw|
int totalPage){ A)n_ST0
return currentPage == totalPage || totalPage == LZ_VLW9wE
,S`n?.&& 7
0 ? false : true; 5O]tkHYR
}
p )JR5z
@Drl5C}+
SQK82/
} 8ly)G
K(upzn*a
06AgY0\
gw,K*ph}q
>^g2Tg:
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。 QEt"T7a[/
>>KI_$V
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 )GG9[%H!
xgIb6<qwY
做法如下: aIa<,
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 '12*'Q+{+
RDDA^U7y#
的信息,和一个结果集List: tb~E.Lm\
java代码: l]zQSXip
L1!~T+%uQ
Ir>4- @
/*Created on 2005-6-13*/ s;oe Qa}TB
package com.adt.bo; hv#$Zo<
&K'*67h
import java.util.List; lJFy(^KQG,
w>X@
,
import org.flyware.util.page.Page; t6+W
y]@JkF(
/** I(R%j]LX&
* @author Joa rMIX{K)'f
*/ Qm3F=*)d
publicclass Result { d]sqj\Q57
-n|>U:
private Page page; AzJ;EtR
o[Qb/ 7
private List content; GP4!t~"1
r?[[.zm"7
/** e'$[PF
* The default constructor qQ)1+^
*/ T$u'+*
Xx
public Result(){ xf;>o$oN0P
super(); UJqh~s
} IowXVdm@6
+=9iq3<yfS
/** <\$"U5"`
* The constructor using fields 1K/ :
* 1HNP@9ga
* @param page F!hjtIkPj
* @param content fTR6]i;
*/ 6:%lxG
public Result(Page page, List content){ )ddJ\:
this.page = page; R$l-
7YSt
this.content = content; bFN/{^SB
} n7;jME/!
N5zWeFq@6
/** up['<Kt+a
* @return Returns the content. L$O\fhO?
*/ ^ICSh8C
publicList getContent(){ h&L-G j
return content; )_C>hWvo_
} /hqn>t
!$1qnsz
/** <h9nt4F
* @return Returns the page. baG_7>Q9H
*/ .up[wt gN
public Page getPage(){ U'F}k0h?\'
return page; Ek `bPQ5
} .GJbrz
ly34aD/p~,
/** q
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* @param content lbt8S.fx
* The content to set. D1-w>Y#
*/ pm=O.)g4`
public void setContent(List content){ R2~y<^.V`Y
this.content = content; RjviHd#DXn
} oh$"?N7n1
:^`j:B
/** n6Uh%rO7S|
* @param page V#$QKn`;
* The page to set. fgL"\d}
*/ ,sc#l<v
publicvoid setPage(Page page){ xV+\R/)x
this.page = page; ?K pDEH~\
} u{=h%d/
} C TG^lms
V2?{ebx`
yc]_ ?S>9
"4WnDd5"
T=pP
2. 编写业务逻辑接口,并实现它(UserManager, _J\zj
U3B&3K} ~
UserManagerImpl) +-;v+{
java代码: qh6b;ae\x
r1IvA^X
*jc
>?)k
/*Created on 2005-7-15*/ ,2Ed^!`
package com.adt.service; 6<\dQ+~
rMJ@oc
import net.sf.hibernate.HibernateException; ~.^:?yCA
m=E/um[D
import org.flyware.util.page.Page; :kI[Pf!z
vgtAJp+p*
import com.adt.bo.Result; 'MYKAnZ-i
BTr;F]W
/** 1yF9zKs&_
* @author Joa Y9f7~w^s
*/ <?KgzIq2
publicinterface UserManager { sdCG}..`
V}<<?_
public Result listUser(Page page)throws fFbJE]jW
P]}:E+E<.I
HibernateException; 11QZ- ^
j^b&Q
} L T`T~|pz
9HN&M*}
Y'P^]Q=}_#
k~<Ozx^AyY
e^\(bp+83
java代码: ]6v7iuvI
xv$fw>
@(=?x:j
/*Created on 2005-7-15*/
K%%Ow
package com.adt.service.impl; 3`SH-"{j%
%jj-\Gz!
import java.util.List; )ZLj2H <
g$ )0E<
import net.sf.hibernate.HibernateException; /J-.K*xKt
&,p6lbP
import org.flyware.util.page.Page; K($+ILZ
import org.flyware.util.page.PageUtil; g8Y)90 G
C<:wSS^@1
import com.adt.bo.Result; 0# 1~'e
import com.adt.dao.UserDAO; P;y!Y/$ C
import com.adt.exception.ObjectNotFoundException; ^=-25%&^
import com.adt.service.UserManager; lws.;abm%n
!}P^O(oY
/** @/As|)
* @author Joa D.7cWR`Wp
*/ B(71I;
publicclass UserManagerImpl implements UserManager { |uFb(kL[U
l#ct;KZ
private UserDAO userDAO; J
Z@sk2
Su,<idS
/** |,n(9Ix
* @param userDAO The userDAO to set. ^o Ds*F
*/ 4$2HO`@uN
publicvoid setUserDAO(UserDAO userDAO){ T^d<vH
this.userDAO = userDAO; K\ pZ
} A9Ea}v9:
|iSwG=&
/* (non-Javadoc) /P[u vO
* @see com.adt.service.UserManager#listUser + rN#
\C;Yn6PK0
(org.flyware.util.page.Page) L*Ffic
*/ >W/mRv&
public Result listUser(Page page)throws z/5TYv)S
*pS3xit~
HibernateException, ObjectNotFoundException { %y>*9$<pXe
int totalRecords = userDAO.getUserCount(); 'dQGb-<_<
if(totalRecords == 0) $i8oLSRV
throw new ObjectNotFoundException UDkH'x$=
ri3*~?k00
("userNotExist"); ^Bw"+ 6d
page = PageUtil.createPage(page, totalRecords); Y~( 8<`^
List users = userDAO.getUserByPage(page); 2"
v{
returnnew Result(page, users); IwbV+mWQ
} Vfq-H /+
3M[d6@a
} SJ8
~:"\P
{KTZSs $n
="@f~~
nyhHXVRH
!L|VmLqa
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 J~@W":v
;6]ag< Q
询,接下来编写UserDAO的代码: bS|h~B]rd
3. UserDAO 和 UserDAOImpl:
S[8nGH#m
java代码: { }Afah
)!zg=}V
)WEOqaR]
/*Created on 2005-7-15*/ T9}dgf
package com.adt.dao; vXdI)Sx[
A$P Oc<
import java.util.List;
NQ '|M
}DvT6
import org.flyware.util.page.Page; :W-xsw
$RRh}w\0^
import net.sf.hibernate.HibernateException; vl s+E o]
(S=CxK
/** ffOV7Dxy
* @author Joa 'UCClj;?K
*/ j6*e^
B
publicinterface UserDAO extends BaseDAO { Xe
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h^H)p`[Gme
publicList getUserByName(String name)throws A}uWy^w
z^KBV^n
HibernateException; "[_gRe*2
=jG."o
publicint getUserCount()throws HibernateException; )ZZ6 (O
K[V#Pj9
publicList getUserByPage(Page page)throws gZz5P>^
mX@xV*
HibernateException; *L<<S=g$2
FYg{IKg
} 77]Fp(uI
6%c]{eTd9
VB+_ kR6Zv
?%>S5,f_
8js1m55KT
java代码: R C!~eJG!
]>+ teG:4
o8A(Cg}
/*Created on 2005-7-15*/ [;C*9Nl
package com.adt.dao.impl; u3 4.
K[-G2
import java.util.List; )4GCL(&
QcdAg%"yy
import org.flyware.util.page.Page; .g_Kab3?L
eN TKX
import net.sf.hibernate.HibernateException; {I$zmVG
import net.sf.hibernate.Query; ,G$<J0R1
%x^ U3"7
import com.adt.dao.UserDAO; *M~BN}.
\VAS<?3
/** 2;SiH]HNS
* @author Joa 0n?^I>j
*/ +'g~3A-G
public class UserDAOImpl extends BaseDAOHibernateImpl -0*z"a9<p8
3qp\jh=FE
implements UserDAO { ^7`gf
vri<R8
/* (non-Javadoc) ?j8_j
* @see com.adt.dao.UserDAO#getUserByName )c0 Dofhg
phcYQqR
(java.lang.String) {%Q+Pzl.
*/ 7a%)/)<D
publicList getUserByName(String name)throws / \k\HK8
VF:<q
HibernateException { F{m?:A
String querySentence = "FROM user in class H|d"45J_
)f`oCXh
com.adt.po.User WHERE user.name=:name"; l4E0/F
Query query = getSession().createQuery b5%T)hn=
Z~g7^,-t
(querySentence); #t&L}=G{%
query.setParameter("name", name); @w;&:J9m
return query.list(); P[gYENQ
} kK]L(ZU+
T$Rf
/* (non-Javadoc) to] ~$~Q|>
* @see com.adt.dao.UserDAO#getUserCount() Ij7[2V]c
*/ KA9v?_@{ F
publicint getUserCount()throws HibernateException { D;oX*`
int count = 0; 14 hE<u
String querySentence = "SELECT count(*) FROM Sh U1RQk
5k<0>6;XH
user in class com.adt.po.User"; jH2_Ekgc;_
Query query = getSession().createQuery Cl!qdh6
|)YN"nqg
(querySentence); YGCBDH%6
count = ((Integer)query.iterate().next rn-CQ2{?
5oY^;)\/
()).intValue(); =zwn3L8 fL
return count; yRldPk_
} _VLA2#V>
!='L `.
/* (non-Javadoc) AbOF/g)C
* @see com.adt.dao.UserDAO#getUserByPage k4~2hD<|
u_%L~1+'
(org.flyware.util.page.Page) G@6F<L~$1
*/ {} Zqaf
publicList getUserByPage(Page page)throws ;v%f +
Jw
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HibernateException { yH',vC.
String querySentence = "FROM user in class Sk%*Zo{|
6F3FcUL
com.adt.po.User"; p']oy;t
Query query = getSession().createQuery qbD[<T
te#Wv9x
(querySentence); 0{.[#!CSk
query.setFirstResult(page.getBeginIndex()) t|}}#Z!I[f
.setMaxResults(page.getEveryPage()); pn
aSOyR
return query.list(); 8/ PS#dM\
} /
#D R|
N9BfjT}
} DYW&6+%,hO
?%i~~hfH#N
L-Pq/x2r
t'bhA20Z\
~>>^7oq
至此,一个完整的分页程序完成。前台的只需要调用 7) Qq
' )KuLVE}S
userManager.listUser(page)即可得到一个Page对象和结果集对象 tE;c>=>t
")eY{C
的综合体,而传入的参数page对象则可以由前台传入,如果用 eDS,}Z'
Z3z"c
B
webwork,甚至可以直接在配置文件中指定。 [ih^VlZ
C;XhnqWv+l
下面给出一个webwork调用示例: 4)E$. F^
java代码: g,}_&+q:.M
+Z=DvKsTJ
'Em633
/*Created on 2005-6-17*/ =r>u'wRQ
package com.adt.action.user; D[p`1$E-1v
Isg\ fSK<j
import java.util.List; ]YKxJ''u
FZ=xy[q]~
import org.apache.commons.logging.Log; =nE^zY2m%
import org.apache.commons.logging.LogFactory; kuW^_BROJ
import org.flyware.util.page.Page; IOOK[g.?h
r5'bt"K\>
import com.adt.bo.Result; ! +XreCw
import com.adt.service.UserService; ~r?VXO p"
import com.opensymphony.xwork.Action; }5lC8{wZ
p?'&P!
/** I@:"Qee
* @author Joa -$cO0RSY
*/ 5O"$'iL
publicclass ListUser implementsAction{ w7QYWf'
o!W(
privatestaticfinal Log logger = LogFactory.getLog oR'u&\mB
^BhS*
(ListUser.class); }sW%i#CV
ibh,d.*~g
private UserService userService; |a>,FZv8e
;]^% 6B n
private Page page; dnCurWjdk
.g!K| c
privateList users; *b\&R%6dR
z2[{3Kd*
/* cSYMnB
* (non-Javadoc) 5N:IH@
*
aS,
* @see com.opensymphony.xwork.Action#execute() "43F.!P
*/ N%!{n7`N:
publicString execute()throwsException{ w
L4P-4'
Result result = userService.listUser(page); q0VR&b`?>D
page = result.getPage(); QfRo`l/V9
users = result.getContent(); 63Z^ k(
return SUCCESS; uFn?U)
} /^=8?wK
Nf)$K'/
/** PUErvLt
* @return Returns the page. /-Z}=
*/ '>[Ut@lT;
public Page getPage(){ arN=OB
return page; % !Ih=DZ
} w[OUGn'
@z>DJ>htN
/** t:*1*;
* @return Returns the users. Y]bS=*q
*/
>Ft)v
publicList getUsers(){ QM@zy
return users; i7%`}t
} B0D
jGe%'AN\
/** ]D[\l$(
* @param page T}59m;I
* The page to set. "w3%BbI x
*/ (h'Bz6K
publicvoid setPage(Page page){ r0*Y~
KHw
this.page = page; ;2[),k
} o2!wz8
S
^$!n,
/** JJy.)-R
* @param users `\J,%J
* The users to set. P~s u]+
*/ D.gD4g_O/
publicvoid setUsers(List users){ {%c&T S@s
this.users = users; -quJX;~
} 2@Oz _?O=
z! :0%qu
/** B_
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* @param userService :Q8*MJ3&V
* The userService to set. Z?u}?-b1\H
*/ 3%)@c P:?
publicvoid setUserService(UserService userService){ (C0Wty
this.userService = userService; Z{x)v5yh2V
} m"!Q5[
} OAf}\
[ps4i_
|G_, 1$
l2ie\4dK@
k~)@D| ?
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, jXPbj.
h
s_x
@6
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 zI4d|P
9 !$&1|,*
么只需要: ~BMUea(
java代码: 8.Ufw.
5
AG><5 }
t1wzSG
<?xml version="1.0"?> 5=
T$h;O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ),Hr
3^5h:OaT
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Z<,Hz+
$PRUzFZ
1.0.dtd"> _r>kR7A\{
8:[ l1d86
<xwork> |K9*><P?)2
9sI&d
<package name="user" extends="webwork- *7b?.{
nw(R=C
interceptors"> vo(:g6$
QseV\; z
<!-- The default interceptor stack name ZG-#YF.1
GL~
Wnt
--> -fp/3-
<default-interceptor-ref o`G6!
.5);W;`X
name="myDefaultWebStack"/> q;*'V9#
ESUO I
<action name="listUser" "Mz#1Laby`
=cO5Nt
class="com.adt.action.user.ListUser"> IwRP,MQ~
<param rgDl%X2B
>@Pw{Zh$
name="page.everyPage">10</param> MJkusR/
<result &XCP@@T
g)=$zXWhP
name="success">/user/user_list.jsp</result> bg|dV
</action> ZMLN
;.{Na
;"Aj80
</package> #<X4RJ
'T$Cw\F&
</xwork> T?RN} @D
O(VWJ@EHn
rT\~VJ>+i
mE_%
h=\1ZQKC)
/:ZwGyT;
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 (:F]@vT
+r7hc;+G
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。 ]=9 d'WL
%a|Qw(4\
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 oUO3,2bn
J%n#uUs
l fFRqZ
M?DZShkV_
EV-sEl8ki
我写的一个用于分页的类,用了泛型了,hoho _>BYUPY
bDudETl
java代码: v(GnG
}a#T\6rY
||fw!8E
package com.intokr.util; yYSmmgrX0
^M%P43
import java.util.List; ?PqkC&o[q
ZjY,k
/** ("F$r$9S
* 用于分页的类<br> -2!S>P Zs
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :J_UXtx
* #Hz9@H
* @version 0.01 'CSjj@3 X
* @author cheng v*0J6<
*/ d2V\T+=
public class Paginator<E> { A+GRTwj
privateint count = 0; // 总记录数 > ;#Y0
privateint p = 1; // 页编号 H-nhq-fut
privateint num = 20; // 每页的记录数 a6cU<(WDeh
privateList<E> results = null; // 结果 .dVV#
H
R)ZzRz|/
/** mj'N)6ga
* 结果总数 rsa_)iBC
*/ ~5h4 Gy)
publicint getCount(){ =+ b>d\7xG
return count; S>r}3,]S
} YtKT3u:x
pUS: HJk|
publicvoid setCount(int count){ 4`mf^Kf
this.count = count; SjpCf8Z(
} I'^XEl?
!.^x^OK%y
/** \y%"tJ~N{
* 本结果所在的页码,从1开始 he/rt#
* G[]%1
_QCO
* @return Returns the pageNo. #d3_7rI0V
*/ V= p"1!(
publicint getP(){ -s!J3DB
return p; D\+x/r?-I
} 4H;7GNu
.>}I/+n
/** D
"5|\
* if(p<=0) p=1 $]xH"Z%"
*
`xHpL8i$5
* @param p XR9kxTuk
*/ s8[(
publicvoid setP(int p){ ZMZWO$"K1
if(p <= 0) r7>FH!=:
p = 1; 9M'"q7Kh
this.p = p; R-dv$z0
} G7|d$!%
rqiH!R
/** rp
dv{CUp7
* 每页记录数量 rPBsr<k#5
*/ );AtFP0Y
publicint getNum(){ E2dS@!]V
return num; lhJY]tQt/
} t#_6GL
f4*(rX
/** @(oY.PeS<z
* if(num<1) num=1 V`LE 'E
*/ ,mvFeo;@f
publicvoid setNum(int num){ H)E,([
if(num < 1) ~Q
Q1ZP3
num = 1; ~PQR_?1
this.num = num; h lc!}{$%8
} XUh&an$
^ H2TSaJ;
/** xu"-Uj1
* 获得总页数 ,1B4FAR&
*/ r}e(MT:R'
publicint getPageNum(){ Q?LzL(OioN
return(count - 1) / num + 1; K3h];F!^
} {+cx} `
U';)]vB$
/** ^Ss<<
* 获得本页的开始编号,为 (p-1)*num+1 PPrvVGP
*/ ewN|">WXQ
publicint getStart(){ T"3LO[j+
return(p - 1) * num + 1; bv(+$YR
} E&z^E2
^`dMjeF
/** *oIIcE4g7
* @return Returns the results. W^Fkjqpv
*/ fV7
k {dR
publicList<E> getResults(){ 0vDvp`ie#4
return results; roAHkI
} 5uSg]2:
Gs|a$^V|o
public void setResults(List<E> results){ g'T L`=O
this.results = results; B/K=\qmm
} @oj_E0i3
kSol%C
public String toString(){ *P7n YjG
StringBuilder buff = new StringBuilder >YXb"g@.
P8=J0&5
(); |5FEsts[
buff.append("{"); !,Gavt7f
buff.append("count:").append(count); >wb*kyO7(#
buff.append(",p:").append(p); )v+&l9D
buff.append(",nump:").append(num); oNl-!W
buff.append(",results:").append 5>CeFy
,K6ODtw.
(results); n%;t Va
buff.append("}"); g(s}R ?
return buff.toString(); kO^
} 2,B^OZmw
rGt]YG#C
} -:L7iOzgD
I
Gb'ii=A
wRwx((eb