Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Wvr{l
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 0Z8"f_GK
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 8\lh'8
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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 =zyA~}M2
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分页支持类: vNv!fkl
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java代码: ~pQN#C)CO>
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package com.javaeye.common.util; yk`qF'4]
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import java.util.List; RTm/-6[N
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publicclass PaginationSupport { 9VnBNuT
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publicfinalstaticint PAGESIZE = 30; 2aM7zP[Z
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privateint pageSize = PAGESIZE; RPW46l34
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privateList items; E7MSoBX9M
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privateint totalCount; f_jhQ..g<g
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privateint[] indexes = newint[0]; ;2<5^hgk
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privateint startIndex = 0; ;KlYiu
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public PaginationSupport(List items, int Ku75YFO,5
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totalCount){ -d\sKc
setPageSize(PAGESIZE); CBEf;Ig
setTotalCount(totalCount); pUXoSnIq:
setItems(items); \#_ymM0
setStartIndex(0); gYB!KM *v
} }xk(aM_
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public PaginationSupport(List items, int oBkhb
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totalCount, int startIndex){ At iUTA
setPageSize(PAGESIZE); !@=S,Vc.
setTotalCount(totalCount); Cq\XLh `
setItems(items); } a9Ah:.7/
setStartIndex(startIndex); R c+olJ^5
} T-en|.
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public PaginationSupport(List items, int V\;Xa0
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totalCount, int pageSize, int startIndex){ K*>%,mP$i
setPageSize(pageSize); K oJ=0jM#
setTotalCount(totalCount); ec&/a2M
setItems(items); $a M5jH<
setStartIndex(startIndex); 4E39]vb
} :RIz6Tz
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publicList getItems(){
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return items; ??,[-Oi
} }Kp!,
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publicvoid setItems(List items){ kFn/dQ4|
this.items = items; O[Vet/^)
} MuoE~K2
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publicint getPageSize(){ F8f}PV]b
return pageSize; =-h^j
} SVe]2ONd
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publicvoid setPageSize(int pageSize){ D=0YLQ*rP
this.pageSize = pageSize; SMEl'y
} EwC]%BZP
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publicint getTotalCount(){ k]~o=MLmj
return totalCount; }
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} qjB:6Jq4q
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publicvoid setTotalCount(int totalCount){ 3p%e_?
if(totalCount > 0){ pU$k{^'UK
this.totalCount = totalCount; sQJ\{'g
int count = totalCount / ]r
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pageSize; X1Yw=t~a
if(totalCount % pageSize > 0) ldA_mj{
count++; t'n@yX_
indexes = newint[count]; lPy|>&Yc
for(int i = 0; i < count; i++){ V8^la'_j
indexes = pageSize * ~:ASv>m
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} v:t;Uk^Y
}else{ M3tl4%j
this.totalCount = 0; a:BW*Hy{\
} )1s5vNVa
} )?F&`+
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publicint[] getIndexes(){ d:%b
return indexes; K./qu^+k
} ;TAj;Tf]H
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publicvoid setIndexes(int[] indexes){ $*#a;w7\C
this.indexes = indexes; my (@~'
} QAs)zl0
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publicint getStartIndex(){ U,Z\)+-R
return startIndex; J @Hg7Faz
} |[SHpcq>
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publicvoid setStartIndex(int startIndex){ 6"&cQ>$xh
if(totalCount <= 0) d?zSwLsl
this.startIndex = 0; 1}(22Q;
elseif(startIndex >= totalCount) TeHJj`rdAU
this.startIndex = indexes O~3
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[indexes.length - 1]; i2=- su
elseif(startIndex < 0) W/Dd7G#IC
this.startIndex = 0; L@N%S Sf
else{ D=e*rrL7a
this.startIndex = indexes 4V@%Y,:ee
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[startIndex / pageSize]; Pb5yz-?
} 9\Ii$Mp
} [LYO'-g^F#
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publicint getNextIndex(){ w!F>fcm
int nextIndex = getStartIndex() + s<I)THC
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pageSize; 4MgN
if(nextIndex >= totalCount) 5vx 4F f
return getStartIndex(); msl.{
else W A/dt2D|
return nextIndex; R(1:I@<?E
} hA7=:LG
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publicint getPreviousIndex(){ \+
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int previousIndex = getStartIndex() - Z&
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pageSize; Lq(=0U\"P
if(previousIndex < 0) wvv+~K9jq
return0; Z"`w>c.
else )lG}B U.
return previousIndex; >h7(kj:
} yE:y[k0E
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} y=Y k$:-y
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抽象业务类 GcV/_Y
java代码: btW#ebm
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/** 4 &bmt
* Created on 2005-7-12 7:4c\C0
*/ m$vq%[/#
package com.javaeye.common.business; |Z:yd}d
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import java.io.Serializable; LU6R"c11
import java.util.List; \e86'&
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import org.hibernate.Criteria; vk7IqlEQ
import org.hibernate.HibernateException; lC5zqyG
import org.hibernate.Session; VVJ0?G
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import org.hibernate.criterion.DetachedCriteria; j7}mh
import org.hibernate.criterion.Projections; ,=)DykP
import "Bd-h|J
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org.springframework.orm.hibernate3.HibernateCallback; N:`_Vl
import L=lSW7R
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org.springframework.orm.hibernate3.support.HibernateDaoS -P;3BHS$T
}U}zS@kI
upport; .j4y0dh33
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import com.javaeye.common.util.PaginationSupport; )tlj{ 7p
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public abstract class AbstractManager extends |8` }8vo)
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HibernateDaoSupport { ![z2]L+TB
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privateboolean cacheQueries = false; `l|Oj$
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privateString queryCacheRegion; zyPb\/
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publicvoid setCacheQueries(boolean $ }/tlA&e
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cacheQueries){ >CvhTrPI
this.cacheQueries = cacheQueries; ka_m
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} #9GfMxH
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publicvoid setQueryCacheRegion(String ffP]U4
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queryCacheRegion){ ;hQ[-
this.queryCacheRegion = j/t%7,
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queryCacheRegion; "Q@m7j)(
} 4Sh8w%s
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publicvoid save(finalObject entity){ -r*|N.5c
getHibernateTemplate().save(entity); 0moA mfc
} l%+ &V^:
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publicvoid persist(finalObject entity){ V Rv4p5
getHibernateTemplate().save(entity); #Us<#"fC
} 3eY>LWx
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publicvoid update(finalObject entity){ |X@s {?
getHibernateTemplate().update(entity); R+!U.:-yz
} 4b<|jVl\
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publicvoid delete(finalObject entity){ |uy@v6
getHibernateTemplate().delete(entity); WN]k+0#
} `)cI^!
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publicObject load(finalClass entity, $~5H-wJ
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finalSerializable id){ j \rGU){
return getHibernateTemplate().load b_sasZo
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(entity, id); & %/p;::A
} K~#?Y,}O
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publicObject get(finalClass entity, M4Cb(QAVP
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finalSerializable id){ (?Ko:0+*
return getHibernateTemplate().get Ucv7`W
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(entity, id); P4B|l:
} qt9jZtx
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publicList findAll(finalClass entity){ 0_qr7Ui8(
return getHibernateTemplate().find("from =mLp g4
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" + entity.getName()); 3>n&u,Xe
} '=nmdqP
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publicList findByNamedQuery(finalString igL5nE=n
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namedQuery){ |ufT)+:
return getHibernateTemplate =w`Mc\o "
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().findByNamedQuery(namedQuery); g@ J F
} Xr^ 5Th\
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publicList findByNamedQuery(finalString query, @(L}:]{@
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finalObject parameter){ rOOo42YW`
return getHibernateTemplate ]]y>d!
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().findByNamedQuery(query, parameter); ItLR|LO9
} l!}gWd,H
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publicList findByNamedQuery(finalString query, vRtERFL
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finalObject[] parameters){ MP}-7UA#K
return getHibernateTemplate P,ZQ*Ju
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().findByNamedQuery(query, parameters); Xc+YoA0Ez
} !Gnm<|.
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publicList find(finalString query){ l`~$cK!
return getHibernateTemplate().find 1q;R+65
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(query); '{0O!y[H6
} P'iX?+*
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publicList find(finalString query, finalObject <mP_K^9c
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parameter){ a1_ N~4r`
return getHibernateTemplate().find N5l`Rq^K
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(query, parameter); @[joM*U
} w}6~t\9D
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public PaginationSupport findPageByCriteria '`k
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(final DetachedCriteria detachedCriteria){ K?M~x&Q
return findPageByCriteria ThP~k9-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sRLjKi2D
} lq-F*r\/~+
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public PaginationSupport findPageByCriteria SeZ+&d
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(final DetachedCriteria detachedCriteria, finalint /T
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startIndex){ )+v5H
return findPageByCriteria xK0;saG#
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(detachedCriteria, PaginationSupport.PAGESIZE, |H=5Am
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startIndex); .+Q1h61$T
} Q,9KLi3
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public PaginationSupport findPageByCriteria ~YNzSkz
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(final DetachedCriteria detachedCriteria, finalint JoB-&r}\V*
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pageSize, CBdr1
finalint startIndex){ K~]Xx~F
return(PaginationSupport) 5Th\wTh04
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getHibernateTemplate().execute(new HibernateCallback(){ o4 "HE*
publicObject doInHibernate
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(Session session)throws HibernateException { O>f*D+A-
Criteria criteria = rv)Eg53Q
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detachedCriteria.getExecutableCriteria(session); W@GU;Nr
int totalCount = .0>bnw
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((Integer) criteria.setProjection(Projections.rowCount oT:wGBW
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()).uniqueResult()).intValue(); CNj |vYj
criteria.setProjection F*z>B >{)
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(null); >f9Q&c$R
List items = CXu$0DQ(
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criteria.setFirstResult(startIndex).setMaxResults `{yD\qDyX
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(pageSize).list(); \\Zsxya1
PaginationSupport ps = U1yspHiZ
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new PaginationSupport(items, totalCount, pageSize, rWJRoGk/
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startIndex); we}5'bS>
return ps; CyVi{"aF3
} pi;fu
}, true); 4ke.p<dG
} a~VW?wq
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public List findAllByCriteria(final nJgN2Z
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DetachedCriteria detachedCriteria){ N>s3tGh
return(List) getHibernateTemplate \(?d2$0m
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().execute(new HibernateCallback(){ 0jXDjk5'<
publicObject doInHibernate qbD_
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(Session session)throws HibernateException { u3 +]3!BQ
Criteria criteria = ok-q9dM
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detachedCriteria.getExecutableCriteria(session); cy8r}wD
return criteria.list(); Q^Vch(`&P
} 2nFr?Y3g,
}, true); (Q&jp!WU
} bLggh]Fh
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public int getCountByCriteria(final X)TZ S
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DetachedCriteria detachedCriteria){ /K,@{__JP
Integer count = (Integer) |e+r~).4B
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getHibernateTemplate().execute(new HibernateCallback(){ kDiR2K&
publicObject doInHibernate t1#f*G5
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(Session session)throws HibernateException { >FFp"%%
Criteria criteria = 0!c/4^
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detachedCriteria.getExecutableCriteria(session); H]dN'c-
return K(NP%:
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criteria.setProjection(Projections.rowCount ARJtE@s6Y
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()).uniqueResult(); ye
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} d|
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}, true); }6__E;h#J
return count.intValue(); 6il+hz2&lH
} #LYx;[D6
} i&}LuF8
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用户在web层构造查询条件detachedCriteria,和可选的 ~a>3,v-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 +b dnTV6
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PaginationSupport的实例ps。 qm=9!jqC;
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ps.getItems()得到已分页好的结果集 p:!FB8
ps.getIndexes()得到分页索引的数组 CS xB)-
ps.getTotalCount()得到总结果数 MA mjoH
ps.getStartIndex()当前分页索引 V2 }.X+u&<
ps.getNextIndex()下一页索引 _2})URU<S
ps.getPreviousIndex()上一页索引 H[/^&1P
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !6+V
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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 u])MI6LF
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一下代码重构了。 ;4vx+> -
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我把原本我的做法也提供出来供大家讨论吧: Nm0|U.<
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首先,为了实现分页查询,我封装了一个Page类: 0te[i*G
java代码: $O9#4A;
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/*Created on 2005-4-14*/ *pGbcBQ
package org.flyware.util.page; `b5pa `\4
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/** pmDFmES
* @author Joa QJH~YV\%
* IkLcL8P^
*/ E-#}.}i5
publicclass Page { a&`Lfw"
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/** imply if the page has previous page */ `[4{]jX+<
privateboolean hasPrePage; n6GB2<y
rdm&YM`J
/** imply if the page has next page */ ,HW[l.v
privateboolean hasNextPage; eOd'i{f@F
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/** the number of every page */ VSm{]Z!x
privateint everyPage; GplEad
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/** the total page number */ w5Yt mnP
privateint totalPage; `HM?Fc58
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/** the number of current page */ #Ic-?2Gn4<
privateint currentPage; ~w$ ^`e!]
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/** the begin index of the records by the current @yn1#E,
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query */ Qnv)\M1
privateint beginIndex; nA#dXckoc
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/** The default constructor */ R-Z)0S'ZR
public Page(){ $)M5@KT
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} RZ:=';
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/** construct the page by everyPage `CEHl &w
* @param everyPage $+[
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* */ 8Nf%<nUv
public Page(int everyPage){ /:aY)0F0<&
this.everyPage = everyPage; ft4(^|~
} 32,Y3!%
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/** The whole constructor */ fnU;DS]W
public Page(boolean hasPrePage, boolean hasNextPage, #uH%J<U
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4#wZ#}
int everyPage, int totalPage, T
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int currentPage, int beginIndex){ yK:b$S
this.hasPrePage = hasPrePage; b*"%E,?
this.hasNextPage = hasNextPage; +T]D\];D
this.everyPage = everyPage; X?OH//co
this.totalPage = totalPage; .0'FW!;FV
this.currentPage = currentPage; .L}k-8
this.beginIndex = beginIndex; 5g;i{T/6~x
} |]x>|Z?/u
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/** qgw)SuwW
* @return 77p8|63
* Returns the beginIndex. p u6@X7W"
*/ pK@8= +
publicint getBeginIndex(){
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return beginIndex; <Is~DjIav
} (<xl _L:*.
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/** ps3jw*QZ{5
* @param beginIndex 8iUj9r_
* The beginIndex to set. _T.k/a
*/ 5}"9)LT@@w
publicvoid setBeginIndex(int beginIndex){ EHX/XM
this.beginIndex = beginIndex; @PyZ u7'
} |#`qP^E
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/** JY6^pC}*
* @return :c`Gh< u
* Returns the currentPage. vAjvW&'g
*/ (E]q>'X
publicint getCurrentPage(){ ~~X-$rtU
return currentPage; i5jsM\1j
} 2N[/Cc2Tg/
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/** Alpk5o5B
* @param currentPage ($r-&]y
* The currentPage to set. $irF
*/ Ud'/
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publicvoid setCurrentPage(int currentPage){ `ehcj
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this.currentPage = currentPage; i9j#Tu93 f
} .h[yw$z6
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/** bOS; 1~~
* @return bE>"DPq
* Returns the everyPage. g!DJW
*/ M A
publicint getEveryPage(){ E]dmXH8A
return everyPage; oA]rwaUX
} aV`_@F-8
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/** R-J^%4U`7
* @param everyPage 6>&h9@
* The everyPage to set. |!E: [UH
*/ JBt2R=
publicvoid setEveryPage(int everyPage){ H[D<G9:
this.everyPage = everyPage; I> BGp4 AQ
} .6[7D
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/** VHqHG`}:
* @return GYwU3`{
* Returns the hasNextPage. jcL%_of
*/ +Fa!<txn
publicboolean getHasNextPage(){ ^c| _%/
return hasNextPage; &r)[6a$fW
} 1V:I}~\
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/** v,^W& W.
* @param hasNextPage Z|$M 9E
* The hasNextPage to set. x
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*/ 1U6z2i+y
publicvoid setHasNextPage(boolean hasNextPage){ _kXq0~
this.hasNextPage = hasNextPage; K$/&C:,Q
} &$g{i:)Z
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/** &OsO _F
* @return <sli!rv
* Returns the hasPrePage. F(KsB5OY?
*/ w?:tce
publicboolean getHasPrePage(){ f@Yo]F U
return hasPrePage; ?!HU$>
} O_\%8*;
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/** ^xm%~
* @param hasPrePage d J>~
* The hasPrePage to set. cp$GP*{@
*/ "Tz'j}< 9C
publicvoid setHasPrePage(boolean hasPrePage){ Fj4>)!^kM
this.hasPrePage = hasPrePage; *WaqNMD[%
} N> xdX5
j9xu21'!%
/** )k.}>0K |
* @return Returns the totalPage. 5XoM)
* 5y8VA4L/o
*/ c*.-mS~Z`
publicint getTotalPage(){ @L$!hTaP
return totalPage; dVe,;?+A
} Q>(a JF
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/**
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* @param totalPage 5Ky(C6E$s
* The totalPage to set. * o{7 a$V
*/ V:h7}T95
publicvoid setTotalPage(int totalPage){ O',Vce$
this.totalPage = totalPage; LyH1tF
} !|Wf
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} ,49Z/P
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Qk72ra)
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 +/ rt'0o
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个PageUtil,负责对Page对象进行构造: 2Gh&h(
java代码: lg
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/*Created on 2005-4-14*/ sGa}Cf;H@g
package org.flyware.util.page; Ad&VOh+0
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import org.apache.commons.logging.Log; wJj:hA}
import org.apache.commons.logging.LogFactory; LXqPNVp#
EF6h>"']/
/** Cxeam"-HTt
* @author Joa H*e +
2
* +z4E:v
*/ BP}@E$
publicclass PageUtil { h4#'@%
1mD)G55Ep
privatestaticfinal Log logger = LogFactory.getLog dci<Rz`h
_b$ yohQ
(PageUtil.class); -9::M}^2
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/** 2VzYP~Jg
* Use the origin page to create a new page 2+_a<5l~
* @param page ,l Y4WO
* @param totalRecords Xv3pKf-K
* @return TJ1h[
*/ Wy%FF\D.Y
publicstatic Page createPage(Page page, int "([/G?QAG
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totalRecords){ tuLNGU
return createPage(page.getEveryPage(), T<-_#}.Hn
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page.getCurrentPage(), totalRecords); ~Up{zRD"B
} 4(p`xdr}K
s VHk;:e>x
/** sn"z'=ch
* the basic page utils not including exception xv&h>GOg
yzv"sd[8N
handler 1jej7p>K
* @param everyPage `nKN|6o#x
* @param currentPage ^=5x1<a9$
* @param totalRecords +IO>%
* @return page H8B$#.
*/ z:4_f:70
publicstatic Page createPage(int everyPage, int {
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@$~IPg[J
currentPage, int totalRecords){ n}I?.r@e
everyPage = getEveryPage(everyPage); &gPP#D6A
currentPage = getCurrentPage(currentPage); &O^-,n
int beginIndex = getBeginIndex(everyPage, Z"RgqNf
*~>p;*
currentPage); X'-Yz7J?o
int totalPage = getTotalPage(everyPage, !|up"T I
7f4O~4.[i
totalRecords); :eSsqt9]9
boolean hasNextPage = hasNextPage(currentPage, &7oL2Wf
7[w<v(Rc
totalPage); vFB^h1k~.M
boolean hasPrePage = hasPrePage(currentPage); H>A6VDu
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returnnew Page(hasPrePage, hasNextPage, 2 rr=FJ
everyPage, totalPage, [orL.D]
currentPage, [iEz?1.,
S>r",S
beginIndex); >=|p30\b
} ;0Pv49q
nQoQNB
privatestaticint getEveryPage(int everyPage){ J|].h
return everyPage == 0 ? 10 : everyPage; kw@^4n+M
} (
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privatestaticint getCurrentPage(int currentPage){ fum.G{}
return currentPage == 0 ? 1 : currentPage; P.qzP/Ny
} I{jvUYrKH
]jFl?LA%7
privatestaticint getBeginIndex(int everyPage, int EG;E !0
RQb}t,
currentPage){ @1Q-.54a
return(currentPage - 1) * everyPage; Pal=I)
} OU"%,&J
hd u2?v@
privatestaticint getTotalPage(int everyPage, int 8M@'A5]
[d8Q AO1;)
totalRecords){ RGE(#
int totalPage = 0; {X&lgj
80wzn,o
S
if(totalRecords % everyPage == 0) ?UZt30|1
totalPage = totalRecords / everyPage; ?)y^ [9
else +)iMJ]>
totalPage = totalRecords / everyPage + 1 ; (rd
[tc
M{Z
;7n'
return totalPage; m$kQbPlatN
} lOk8VlH<h
9MYk5q.X:
privatestaticboolean hasPrePage(int currentPage){ pX
^^0
return currentPage == 1 ? false : true; QCF'/G
} ^w.hI5ua)
&J*M
privatestaticboolean hasNextPage(int currentPage, 1XMR7liE
{^
b2nOMv
int totalPage){ ^Aq0<
return currentPage == totalPage || totalPage ==
G$+v |z
$KO2+^%y
0 ? false : true; LWN{
} RI0^#S_{
B-R#?Xn:!I
sa(.Anmlj
} `;E/\eG"
M .b8 -`V
4
"HX1qP
>F7w]XH
FT@uZWgQ=
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。 M
9t7y
x8PT+KC
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 r8J 7zTD&
#Ub_m@@4
做法如下: Z[oEW>_A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 lUm(iYv;H
VN0We<\Z
的信息,和一个结果集List: CwA_jOp
java代码: ViPC Yt`of
\=AA,Il
'J|)4OG:
/*Created on 2005-6-13*/ .B#
.
package com.adt.bo; _1p8(n
DK)W
,z|
import java.util.List; " B#|C'
bf"'xn9
import org.flyware.util.page.Page; i#]e&Bru5
GQqGrUQ*}
/** 6lSz/V;
* @author Joa G^~[|a4`
*/ Xv8-<Ks
publicclass Result { L>1hiD&
xc:E>-
private Page page; PgWWa*Ew
9CY{}g
private List content; #) aLD0p
YAr6cl
/** Ae+)RBpc
* The default constructor /o9T [^\
*/ ,^UqE{
public Result(){ Az`Aa0h]7
super(); c=oDzAzuV\
} fFjpQ~0
$;qi-K3j
/** G*fo9eu5$
* The constructor using fields I,j4 BU4
* Tlsh[@Q
* @param page /kW Z 8Z
* @param content mgq!)
*/ $KiCs]I+
public Result(Page page, List content){ Oj5UG*
this.page = page; &O&HczO
this.content = content; 0
&zp
} Ts5)r(
\G" S7
/** M&Ka^h;N
* @return Returns the content. =ejj@c
*/ 8M,*w6P
publicList getContent(){ eqo0{e
return content; !eLj +0
} ti\
${C3
m1"m KM
/** yn4T!r "
* @return Returns the page. =3e7n2N)
*/ "O&93#8
public Page getPage(){ Q`ua9oIJ=
return page; ^SdF\uk{?6
} T*z]<0E]
#~*v##^vFH
/** )h{&O
,s
* @param content )`\hK
* The content to set. xY^sC56Z
*/ 25Dl4<-Z
public void setContent(List content){ ~MC|
this.content = content; Gm=qn]c
} 9wgB JJl7
<n2@;`D
/** 8+zW:0"[
* @param page iNO>'7s7
* The page to set. 37#&:[w>
*/ _C?j\Wy
publicvoid setPage(Page page){ jEc_!Q
this.page = page; YG "Ta|@5
} L:R4&|E/t
} {f/qI`
f-ltV<C_
3[YG
BM(
v, $r.g;
O\5%IfB'"
2. 编写业务逻辑接口,并实现它(UserManager, /k#-OXP~
067c/c
UserManagerImpl) {keZ_2
java代码: a~$XD(w^
yk+ 50/L
88g3<&
/*Created on 2005-7-15*/ i]JTKL{\q
package com.adt.service; 8:ubtB
S*h52li
import net.sf.hibernate.HibernateException; D!<F^mtl
wu41Mz7
import org.flyware.util.page.Page; vwCQvt
L.Y3/H_
import com.adt.bo.Result; 8Sbz)X
[);oj<
/** DiC z%'N
* @author Joa H?$dnwR
*/ xEb>6+-F@
publicinterface UserManager { #8$?#
dT
Y"Cf84E
public Result listUser(Page page)throws j]u!;]
\Z-th,t
HibernateException; y7Po$ )8l
3uL
f0D
} >p_W(u@ z$
}K {1Bm@S
iHa?b2=)
=u.@W98, K
XlmX3RU
java代码: 5E!C?dv(z
&5CRXf
5ut| eD`3
/*Created on 2005-7-15*/ L*@`i ]jl
package com.adt.service.impl; 3Cf9'C
t^s&1#iC
import java.util.List; &i#$ia r
LC%ococ
import net.sf.hibernate.HibernateException; -IPo/?}
<r%K i`u(p
import org.flyware.util.page.Page; +;N]34>S7
import org.flyware.util.page.PageUtil; Q@D7\<t
VtBC~?2U)B
import com.adt.bo.Result; YIQD9
import com.adt.dao.UserDAO; yx-{PjX
import com.adt.exception.ObjectNotFoundException; b!<_ JOL2.
import com.adt.service.UserManager; s :vNr@TS
qBA)5Sv\V
/** GkGiQf4hh
* @author Joa _&gi4)q
*/ z7K{ ,y
publicclass UserManagerImpl implements UserManager { Q$%apL
C$[d~1t6
private UserDAO userDAO; 7]=&Q4e4
#'L<7t
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/** i8iT}^
* @param userDAO The userDAO to set. x|H`%Z
*/ bA;OphO(
publicvoid setUserDAO(UserDAO userDAO){ a:FU- ^B4~
this.userDAO = userDAO; O-?rFNavxp
} IH|zNg{\Y
TI>5g(:3\
/* (non-Javadoc) r\NqY.U&
* @see com.adt.service.UserManager#listUser 5ggyk0
|v&)O)Jg
(org.flyware.util.page.Page) Xs03..S
*/ Tz
@<hE
public Result listUser(Page page)throws ``MO5${
K'A+V
HibernateException, ObjectNotFoundException { lriezI
int totalRecords = userDAO.getUserCount(); |9*Rnm_
if(totalRecords == 0) !)s(Lv%]
throw new ObjectNotFoundException L/k35 x8
XlppA3JON|
("userNotExist"); g~lv/.CnA+
page = PageUtil.createPage(page, totalRecords); "?"
:
List users = userDAO.getUserByPage(page); -&+:7t
returnnew Result(page, users); Cbbdq%ySI
} ~i,d%a
&l(T},-X
} 7)?C+=,0
x :SjdT
w$]G$e
kmQ:wf:
LdUz;sb
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G% F#I
B=SA
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询,接下来编写UserDAO的代码: g2OnLEF]s
3. UserDAO 和 UserDAOImpl: A95f!a
java代码: U/>I! 7oe
O=K
lc+Oo
&RR;'wLoQT
/*Created on 2005-7-15*/ WQ|Ufl;
package com.adt.dao; $^x=i;>aK.
Fh~9(Y#
import java.util.List; *5'8jC"2g
YPK@BmAdE
import org.flyware.util.page.Page; o&JoeKXor
,!=
sGUQ)
import net.sf.hibernate.HibernateException; 5Tsz|k
"x$@^
/** ,&[o:jTk
* @author Joa I4Do$&9<D
*/ CD1Ma8I8
publicinterface UserDAO extends BaseDAO { R|?n
B`SX3,3
publicList getUserByName(String name)throws <spG]Xa<
x[A|@\Z
HibernateException; 757&bH|a
l)r\SE1
publicint getUserCount()throws HibernateException; y-pdAkDh
:zW? O#aL-
publicList getUserByPage(Page page)throws 01(U)F\
[* xdILj
HibernateException; 7F`\Gz_2
qlhc"}5x }
} fTxd8an{
<IrhR,@M,L
Q%CrB>|@
Q Xd`P4a
(Mc{nFqS
java代码: !t% 1G.
P|NGAd
5BrN
uR$
/*Created on 2005-7-15*/ ju2H0AQ
package com.adt.dao.impl; `E~"T0RX
:tWkK$
import java.util.List; PYQ0&;z
CvIuH=,
import org.flyware.util.page.Page; f]*;O+8$LN
enk`I$Xx
import net.sf.hibernate.HibernateException; ch#)XomN
import net.sf.hibernate.Query; 3MQHoxX
WUS%4LL(
import com.adt.dao.UserDAO; _'p/8K5)=
0>[]Da}
/** T
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* @author Joa |AvPg
*/ .7.G}z1
public class UserDAOImpl extends BaseDAOHibernateImpl k$=L&id
le:}MM
implements UserDAO { ~n -N
gmp@ TY=:L
/* (non-Javadoc) @tT`s^e
* @see com.adt.dao.UserDAO#getUserByName O%%Q./oh
$uLTYu
(java.lang.String) @5d^ C
*/ 6{I7=.V
publicList getUserByName(String name)throws &D<6Go/)_*
>p&"X 2
@
HibernateException { bAlty}U
String querySentence = "FROM user in class 1_7p`Gxt[/
2K4Xu9-i:b
com.adt.po.User WHERE user.name=:name"; <v1H1'gv
Query query = getSession().createQuery Boj R"
&n*ga$Q
(querySentence); SY9 5s
query.setParameter("name", name); "]3o933D
return query.list(); 7a[6@
} p$"~vA .
!S~)U{SSK
/* (non-Javadoc) D)MFii1J~
* @see com.adt.dao.UserDAO#getUserCount() (jKqwVs.:
*/ Az8b_:=
publicint getUserCount()throws HibernateException { K0>;4E>B
int count = 0; ;9~YQW@|
String querySentence = "SELECT count(*) FROM 0L;,\&*u
*mV?_4!,f7
user in class com.adt.po.User"; [__P-h{J
Query query = getSession().createQuery Fs>MFj
[XPAI["
(querySentence); r'ilJ("
count = ((Integer)query.iterate().next Zzlt^#KLx
=lv(
()).intValue(); *BxU5)O
return count; ; &rxwL
} 9z?c0W5x
UhR^Y{W5
/* (non-Javadoc) qKSR5 #
* @see com.adt.dao.UserDAO#getUserByPage &$ }6:
MoxWnJy}
(org.flyware.util.page.Page) dkC_Sh{
*/ #0)TS
publicList getUserByPage(Page page)throws 6l,6k~Z9
O0y0'P-rJq
HibernateException { 75>%!mhM
String querySentence = "FROM user in class Y"ta`+VJ
`pv
com.adt.po.User"; Dj= {%
Query query = getSession().createQuery :xg
J2
;\"5)S
(querySentence); 5%wA"_
query.setFirstResult(page.getBeginIndex()) 9t`yv@.>N
.setMaxResults(page.getEveryPage()); ty[%:eG#
return query.list(); Ud"_[JtGM
} <|'ETqP<+
mR2"dq;U
} #Br`;hL<T
ZYB5s~;eB"
=f@71D1
2cu2S"r
=H: N!!:
至此,一个完整的分页程序完成。前台的只需要调用 Obu 6k[BE.
=2*2$
userManager.listUser(page)即可得到一个Page对象和结果集对象 _e8Gt6>
nUs=PD3)
的综合体,而传入的参数page对象则可以由前台传入,如果用
6x5Q*^w
-7oIphJ=\
webwork,甚至可以直接在配置文件中指定。 Z9H2! Cp
^0"fPG`
下面给出一个webwork调用示例: GRpwEfG
java代码: t<+>E_Xw
bfUKh%!M
j*?E~M.'1K
/*Created on 2005-6-17*/ ?gu!P:lZS
package com.adt.action.user; GQ85ykky
EId>%0s5
import java.util.List; Y q/vym-O5
Gqq<-drR
import org.apache.commons.logging.Log; %/)z!}{
import org.apache.commons.logging.LogFactory; 1z; !)pG.
import org.flyware.util.page.Page; DZ`,QWuA
|+~P; fG
import com.adt.bo.Result; O*2{V]Y
@
import com.adt.service.UserService; +-x+c:
IxA
import com.opensymphony.xwork.Action; /_JR7BB^X,
jn]l!nm
/** WCaMPz
* @author Joa 6wOj,}2Mn
*/ ui"`c%2n
publicclass ListUser implementsAction{ 1C=42ZZ&2
n\7>_
privatestaticfinal Log logger = LogFactory.getLog Z3<lJk\Y
W-D4"
G@
(ListUser.class); Hl}m*9<9us
g\+!+!"~
private UserService userService; 7h.[eMLPB
hQ)?LPUB
private Page page; Yjy%MR
|Eu#mN
privateList users; Q(WfWifu-|
8z-wdO\
/* ]Gj%-5G
* (non-Javadoc) b;`MHEzw&q
* '[[IalQ?
* @see com.opensymphony.xwork.Action#execute() Dir# [j
*/ t&yuo E
publicString execute()throwsException{ 5s0`T]X-
Result result = userService.listUser(page); W;X:U.
page = result.getPage(); EnMc9FN(y
users = result.getContent(); 1JS5 LS
return SUCCESS; 6DEH|2
} cri-u E?
@Rd`/S@
/** E)'T;%
* @return Returns the page. uw>y*OLU+
*/ mmC MsBfL
public Page getPage(){ X#W6;?Z\
return page; B|>eKI
} }PMlG
Qc Xw -
/** !bW^G}
<t
* @return Returns the users. :p1_ij]ND
*/ f'j<v
publicList getUsers(){ `)i4ZmE|
return users; )Zvn{
} *P12d
rv~OfL
/** ;%AY#b4m
* @param page T[ zEAj
* The page to set. U
d+6=Us{
*/ U,<?]h
publicvoid setPage(Page page){ q)"yP\
this.page = page; h?QGJ^#8
} gE23C*!'&:
H'@@%nO(
/**
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* @param users Qoz4(~I
* The users to set. CT.hBz
-S
*/ o3'Za'N.
publicvoid setUsers(List users){ PTF|"^k+
this.users = users; V4*/t#L/
} 9]S;%:64
8[)"+IFN
/** 9*a"^
* @param userService bz\nCfU
* The userService to set. H9=8nLb.
*/ TaG(sRI
publicvoid setUserService(UserService userService){ $3Sm?
this.userService = userService; u~'j?K.^
} OV^?cA
} VkC1\L6
gue~aqtJ
()_^:WQO?
/p{$HkVw
\NL*$SnxP
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, q] '2'"k
1:Raa 5
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 ZyrVv\'
AHplvksb
么只需要: e1H2w?
s
java代码: _dVA^m
T\TKgO=)
aslb^
<?xml version="1.0"?> ~kZ?e1H
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )9{!=k
;C5
J^xHI
1.0//EN" "http://www.opensymphony.com/xwork/xwork- g0s*4E
IP#qT
`=}
1.0.dtd"> <[z9*Tm
)%I62<N,z
<xwork> 1[(/{CClB
[58qC:
<package name="user" extends="webwork- :W[d&e
V4?]NFK
interceptors"> U5;Y o+z
LV]F?O[K=
<!-- The default interceptor stack name 9,wU[=. 0
Ix.Y_}
--> j2%M-y4E
<default-interceptor-ref (7|!%IO.
^}Gu'!z9D
name="myDefaultWebStack"/> $mst\]&;
Wl{}>F`W[
<action name="listUser" (+9^)No
o[k,{`M0
class="com.adt.action.user.ListUser"> %xwtG:IKEV
<param zRA,Yi4;+
1v9#Fr Y
name="page.everyPage">10</param> <)$JA
<result T:VFyby\w
_sqV@ J
name="success">/user/user_list.jsp</result> o+T, O+i
</action> g-2(W
Hg+bmwM
</package> 8^qLGUxz
Dp;6CGYl?
</xwork> oN.#q$\` k
3Ebkq[/*%
4nD U-P#f
.10$n*
6hf6Z3
TE@bV9a
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 90
pt'Jg
~=c[?:
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 xY`$j'u
0'II6,:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8'VcaU7Nh
zy@
nBi^
6iJ\7
DZU} p
@HP7$U"
我写的一个用于分页的类,用了泛型了,hoho $McbVn)~f
f>ilk Q`
java代码: Eh.NJI(
@l@erCw@
+r 8/\'u-
package com.intokr.util; f26hB;n
JrwR:_+|
import java.util.List; j%Z%_{6Ds*
S!.H _=z%p
/** +Am\jsq
* 用于分页的类<br> KOVR=``"/
* 可以用于传递查询的结果也可以用于传送查询的参数<br> nCdxn#|
* Nr0}*8#j
* @version 0.01 /\UFJ
* @author cheng ; +R
*/ 7Ezy-x2h
public class Paginator<E> { f
_*F&-L
privateint count = 0; // 总记录数 kPFqsq
privateint p = 1; // 页编号 *ta?7uSiT
privateint num = 20; // 每页的记录数 @SH$QUM(
privateList<E> results = null; // 结果 8G|kKpX
= ^_4u%}
/** U<.,"`=l
* 结果总数 $g]'$PB
*/ bv4G!21]*;
publicint getCount(){ W3 2]#M=
return count; pcO0xrI
} oC1Nfc+
^#&:-4/
publicvoid setCount(int count){ SR*KZ1U
this.count = count; U|)CZcM
} 9*j$U$:'
[BKX$A:Y
/** M}xyW"yp
* 本结果所在的页码,从1开始 C *U,$8j|}
* cP`[/5R
* @return Returns the pageNo. h4k.1yH;
*/ rnS&^
publicint getP(){ W60C$*h
return p; +|TFxaVz
} &WoS(^
o@A|Lm.
/** #m36p+U
* if(p<=0) p=1 4~mmP.c
* ^Qa!{9o[
* @param p nypG
*/ 0XUWK@)P
publicvoid setP(int p){ 5 p! rZ
if(p <= 0) \ 3HB
p = 1; zpBkP-%}E
this.p = p; =p7eP
} ,K~r':ht
p1B~F
/** 2 s<uT
* 每页记录数量 db0]D\
*/ ])H[>.?K
publicint getNum(){ T~-OC0
return num; TjLW<D(i>
} e)A-.SRiO$
RGV}c#
/** < r7s,][&
* if(num<1) num=1 vOi4$I~CJ
*/ "6
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publicvoid setNum(int num){ WHKe\8zWq
if(num < 1) ?)?}^
num = 1; x{#W84
this.num = num; k{-#2Qz
} PQA}_o
6PdLJ#LS
/** }>< v7
* 获得总页数 qpXsQim$~
*/ 8a,pDE
publicint getPageNum(){ L@>$
Aw
return(count - 1) / num + 1; IJ#+"(?7,u
} Auk#pO#
d@e2+3<
/** M
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* 获得本页的开始编号,为 (p-1)*num+1 5VhJ*^R`y
*/ RgTrj
publicint getStart(){ o%sx(g=q6
return(p - 1) * num + 1; m%)Cw)t
7
} wC`+^>WFo
o#=@!m
/** Dwuao`~Xm
* @return Returns the results. _fE$KaP
*/ zyPc<\HoK
publicList<E> getResults(){ $fFh4O4
return results; gjDxgNpa
} 8qWN~Gk1p{
AOscewQ
public void setResults(List<E> results){ QP:|D_k
this.results = results; 5}NTqN0@
} ;?.w!|6
32x[6"T
public String toString(){ hG8<@
StringBuilder buff = new StringBuilder \^]*T'>b
?`T-A\A=
(); ^SC2k LI
buff.append("{"); q!4eVg*
buff.append("count:").append(count); ;<N%D=;}@
buff.append(",p:").append(p); &"'Z)iWm
buff.append(",nump:").append(num); uN+]q qCf
buff.append(",results:").append "^NsbA+
4I!g?Moh
(results); Z)'gj
buff.append("}"); C q)Cwc[H
return buff.toString(); ckdXla
} y ]D[JX[
U\GuCw
} ,4H/>yPw
H?cJ'Q,5
br%l>Y\"