Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K .cMuh
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &46h!gW
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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 -{i;!XE$SR
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 ?Sj3-*/?
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分页支持类: 5!r?U
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java代码: cn$E?&-
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package com.javaeye.common.util; (^'TT>2B
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import java.util.List; Gb6t`dSzz
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publicclass PaginationSupport { ST3aiyG
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publicfinalstaticint PAGESIZE = 30; 7z'l}*FRD
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privateint pageSize = PAGESIZE; ve2GRTO^aC
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privateList items; s+>VqyHgf
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privateint totalCount; XSkN9LqZ
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privateint[] indexes = newint[0]; bv`gjR
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privateint startIndex = 0; yjODa90!G
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public PaginationSupport(List items, int =(ts~^
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totalCount){ utxT$1iJn~
setPageSize(PAGESIZE); P 8DY*B k
setTotalCount(totalCount); GwHMXtj4
setItems(items); 5|!x0H;
setStartIndex(0); -o<L%Y<n2
} 9^Q:l0|
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public PaginationSupport(List items, int ;aKdRhDo
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totalCount, int startIndex){ p#W[he
setPageSize(PAGESIZE); iha{(-
setTotalCount(totalCount); & IVwm"
setItems(items); $Scb8<
setStartIndex(startIndex); 7u]0dHj
} t>QAM6[
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public PaginationSupport(List items, int Be+CV">2
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totalCount, int pageSize, int startIndex){ ">]v'h(s
setPageSize(pageSize); [Q&{#%M
setTotalCount(totalCount); N"MuAUB:K
setItems(items); pqO}=*v@
setStartIndex(startIndex); 2Q`@lTUv
} 6/@"K
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publicList getItems(){ @e# eAJhU
return items; :SilQm*Pl
} 8 munw
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publicvoid setItems(List items){ keNPlK%>
this.items = items; YHN@?}T()
} a<l(zJptG
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publicint getPageSize(){ /NCEZ@2BN,
return pageSize; j?D=Ij"o
} [$)C(1zY
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publicvoid setPageSize(int pageSize){ .8hB <G
this.pageSize = pageSize; 8jW{0&ox)
} }I;A\K]
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publicint getTotalCount(){ =s`\W7/;{-
return totalCount; K0RY2Hiw
} ZzPlIl}\
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publicvoid setTotalCount(int totalCount){ ;u!qu$O
if(totalCount > 0){ \D(6t!Ox
this.totalCount = totalCount; GGk.-Ew@
int count = totalCount / U.<';fKnT
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pageSize; WbC|2!
if(totalCount % pageSize > 0) vR<Y1<j
count++; vt}+d
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indexes = newint[count]; 8qL*Nf
for(int i = 0; i < count; i++){ dABmK;
indexes = pageSize * sh(G{Yz@
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i; @0A7d
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} @mBZu!,
}else{ N*w/\|
this.totalCount = 0; kFmd):U!R
} {LfVV5?
} 4VINu9\V
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publicint[] getIndexes(){ F2!C^r,~L
return indexes; !K^.r_0H.
} v
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publicvoid setIndexes(int[] indexes){ _2+}_ >d
this.indexes = indexes; |r5 n p
} o5KpiibFM
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publicint getStartIndex(){ x'_I{$C&
return startIndex; ^l|{*oj2
} WCT}OiLsL
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publicvoid setStartIndex(int startIndex){ Lbk?( TL
if(totalCount <= 0) K5gh7
this.startIndex = 0; ^T`)ltI]V
elseif(startIndex >= totalCount) Xwy0dXko
this.startIndex = indexes 1 zIFQ@
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[indexes.length - 1]; ?}"$[6.
elseif(startIndex < 0) vcs=!Ace
this.startIndex = 0; R{GOlxKs C
else{ XB,
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this.startIndex = indexes KB49~7XjQ@
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[startIndex / pageSize]; s*{l}~fPkW
} Pn|A>.)z
} i-[ic!RnKj
hN*,]Z{
publicint getNextIndex(){ uu L"o
int nextIndex = getStartIndex() + c'n EbelE
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pageSize; n{JBC%^g
if(nextIndex >= totalCount) M72.
return getStartIndex(); .g71?^?(
else _4F(WC co
return nextIndex; wYy=Tl-N
} c?B@XIl
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publicint getPreviousIndex(){ )8]O|Z-CU
int previousIndex = getStartIndex() - S~L$sqt
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pageSize; {/`iZzPg
if(previousIndex < 0) Yl%1e|WV
return0; `>&V_^y+
else a;JB8
return previousIndex; (c;F%m|
} -Yx'qz@
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} !gA<9h
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抽象业务类 0dxEV]
java代码: dPplZ,Y%
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/** o))z8n?b
* Created on 2005-7-12 m
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*/ /H.w0fu&.S
package com.javaeye.common.business; L+,p#w
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import java.io.Serializable; =Hplg>h)
import java.util.List; i]&C=X
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import org.hibernate.Criteria; &nkYJi(!
import org.hibernate.HibernateException; 3)\jUVuj
import org.hibernate.Session; U;QTA8|!&
import org.hibernate.criterion.DetachedCriteria; dbM~41C6
import org.hibernate.criterion.Projections; A+P9M \u.
import \6o%gpUkD
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org.springframework.orm.hibernate3.HibernateCallback; {3n|=
import ?O3E.!Q|
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org.springframework.orm.hibernate3.support.HibernateDaoS <QbD ; (%
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upport; FOJ-?s(
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import com.javaeye.common.util.PaginationSupport; l~P%mVC3m
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public abstract class AbstractManager extends 7\x7ySM
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HibernateDaoSupport { ;f,`T
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privateboolean cacheQueries = false; 3!E*h0$}
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privateString queryCacheRegion; o
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publicvoid setCacheQueries(boolean 8R?X$=$]!.
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cacheQueries){ dr3j<D-Q
this.cacheQueries = cacheQueries; x(oL\I_Z
} to9~l"n.s
}j<:hDQP
publicvoid setQueryCacheRegion(String y4sKe:@2
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queryCacheRegion){ 4WCWu}
this.queryCacheRegion = dH:z_$Mg
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queryCacheRegion; [7x,&
} #dyz
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publicvoid save(finalObject entity){ "#zSk=52z
getHibernateTemplate().save(entity); y!_*CYZ~m
} S,ZlS<Z#
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publicvoid persist(finalObject entity){ I`hltJM'
getHibernateTemplate().save(entity); s
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} 7{jB!Xj
}!_x\eq^
publicvoid update(finalObject entity){ Jr|"QRC
getHibernateTemplate().update(entity); ~,#zdm1r@
} sBUK v(U)
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publicvoid delete(finalObject entity){ dCq-&3?t
getHibernateTemplate().delete(entity); *}fs@"S
} bY`
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publicObject load(finalClass entity, z[Sq7bbYO
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finalSerializable id){ l Tpn/
return getHibernateTemplate().load O3ij/8f
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(entity, id); |,YyuCQcL[
} 6.#5Ra
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publicObject get(finalClass entity, I*h%e,yIO
: jgvg$fd
finalSerializable id){ NsbC0xLd
return getHibernateTemplate().get 2ed4xhV
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3
(entity, id); R<\5q%@G
}
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publicList findAll(finalClass entity){ !97U2L4
return getHibernateTemplate().find("from ^YVd^<cE
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" + entity.getName()); jLc"1+
} &Bn>
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publicList findByNamedQuery(finalString p7SX,kpt>
}jL_/gvgy
namedQuery){ <HYK9{Q
return getHibernateTemplate
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().findByNamedQuery(namedQuery); r0MUv}p#|L
} =yT3#A~<G
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publicList findByNamedQuery(finalString query, Tt^PiaS!
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finalObject parameter){ gc5u@(P"
return getHibernateTemplate ;Gf,I1d}{
o`tOnwt
().findByNamedQuery(query, parameter); I`e$U
} aC!e#(q
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publicList findByNamedQuery(finalString query, ;i;2cq
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finalObject[] parameters){ &\n<pXQ
return getHibernateTemplate tr[(,kX
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().findByNamedQuery(query, parameters); <n#phU Q
} z2.9l?"rfQ
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publicList find(finalString query){ ^4G%*-
return getHibernateTemplate().find m=m T`EP
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(query); ]t2zwHo#
} OEZ`5"j
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publicList find(finalString query, finalObject ?$chO|QY
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parameter){ rnOg;|u8
return getHibernateTemplate().find vk:k ~
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(query, parameter); HQ187IwpTm
} n0\k(@+k
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public PaginationSupport findPageByCriteria $Gy&
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(final DetachedCriteria detachedCriteria){ Sa8KCWgWh
return findPageByCriteria U{`Q_Uw@$:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); rT#2'-f
} )2pOCAjL2
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public PaginationSupport findPageByCriteria pqT+lai)#
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(final DetachedCriteria detachedCriteria, finalint ce&Q}_
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startIndex){ CjQ)Bu*4
return findPageByCriteria "e-RV
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(detachedCriteria, PaginationSupport.PAGESIZE, (GCe D-
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startIndex);
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} Z&Qz"V>$
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public PaginationSupport findPageByCriteria uc~/l4~N
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(final DetachedCriteria detachedCriteria, finalint av8\?xmo.$
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pageSize,
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finalint startIndex){ .="/n8B
return(PaginationSupport) V7gv@<1<y
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getHibernateTemplate().execute(new HibernateCallback(){ q,Nhfo(
publicObject doInHibernate
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(Session session)throws HibernateException { 2 -C*RHRx
Criteria criteria = 4Ou5Vp&y
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detachedCriteria.getExecutableCriteria(session); @CB&*VoB
int totalCount = r3}Q1b&
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((Integer) criteria.setProjection(Projections.rowCount *x<3=9V
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()).uniqueResult()).intValue(); rlpbLOG`
criteria.setProjection \/8oua_)
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(null); .7K<9K +P
List items = L,/(^0;
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criteria.setFirstResult(startIndex).setMaxResults ]ZI ?U<0
^o8o
(pageSize).list(); e[($rsx
PaginationSupport ps = *NjjFk=R
uE=pq<
new PaginationSupport(items, totalCount, pageSize, `zP{E T_Y
9 *+X^q'
startIndex); ~lQ<#*wl
return ps; B)`@E4i
} N?3BzI%?
}, true); AzZb0wW6p
} q(XO_1W0V
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public List findAllByCriteria(final {Q(R#$)5+
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DetachedCriteria detachedCriteria){ bm\Zp
return(List) getHibernateTemplate DX b=Ku
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().execute(new HibernateCallback(){ Uaz$<K6
publicObject doInHibernate \:5M0
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(Session session)throws HibernateException { R^f-j-$o]
Criteria criteria = \1MMz Z4rf
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detachedCriteria.getExecutableCriteria(session); z#u<]] 5
return criteria.list(); N ]|P||fC
} %NH{%K,
}, true); l\DcXgD
x
} Q~-M B]'
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public int getCountByCriteria(final EG#mNpxE
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DetachedCriteria detachedCriteria){ T$pBgS>
Integer count = (Integer) {x\lK;
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getHibernateTemplate().execute(new HibernateCallback(){ }{S pV
publicObject doInHibernate ]m=2 $mK
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(Session session)throws HibernateException { YsA.,
Criteria criteria = G9AQIU%ii
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detachedCriteria.getExecutableCriteria(session); 6!A+$"
return -oMp@2\e
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criteria.setProjection(Projections.rowCount :(TOtrK@
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()).uniqueResult(); N#&/d nV
} zy\R>4i'#Q
}, true); "eH.<&
return count.intValue(); P>wTp)
} *V[6ta'
} * R_mvJlT
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用户在web层构造查询条件detachedCriteria,和可选的 e"^n^_9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Z9p`78kYyh
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PaginationSupport的实例ps。 Rdj/n :
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ps.getItems()得到已分页好的结果集 _J ZlXY
ps.getIndexes()得到分页索引的数组 RA
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ps.getTotalCount()得到总结果数 |S.;']t+
ps.getStartIndex()当前分页索引 jA,|.P>
ps.getNextIndex()下一页索引 ?@iGECll
ps.getPreviousIndex()上一页索引 lr~c w#h*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ){FXonVP
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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 w<$0n#5
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一下代码重构了。 "3e1 7dsY
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我把原本我的做法也提供出来供大家讨论吧: 2E_d$nsJ
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首先,为了实现分页查询,我封装了一个Page类: F&)(G\
java代码: ~7O.}RP0
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/*Created on 2005-4-14*/ 5169E*
package org.flyware.util.page; #4wia%}u
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/** a8v9j3.
* @author Joa f6U
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* aF5=k:k
*/ N*6lyFcg
publicclass Page { Y:KIaYkk
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/** imply if the page has previous page */ /PTk296@
privateboolean hasPrePage; .yN.
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/** imply if the page has next page */ [l:}#5\]4
privateboolean hasNextPage; n"|1A..^
vfpK|=[7o
/** the number of every page */ du_TiI
privateint everyPage; WEsX+okj
w)Wg 8
/** the total page number */ i_ z4;%#?
privateint totalPage; 2e*"<>aeq
oQ/ Dg+Xp
/** the number of current page */ 7CV}QV}G
privateint currentPage; S0jYk (
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/** the begin index of the records by the current p{W'[A{J .
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query */ 1azj%WY
privateint beginIndex; Gcp!"y=i
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/A"UV\H`f
/** The default constructor */ bd[%=5
public Page(){ uj^l&"
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} zOsk'ZE&
4#Id0['
/** construct the page by everyPage ]^BgSC
* @param everyPage {L.=)zt>
* */ +A%"_7L}
public Page(int everyPage){ L2`a| T=
this.everyPage = everyPage;
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} l2
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/** The whole constructor */ 3}gf%U]L
public Page(boolean hasPrePage, boolean hasNextPage, vq-#%o
CCp&+LRvR
ql2O%B.6?
int everyPage, int totalPage, *Fu;sR2y%:
int currentPage, int beginIndex){ la{Iqm{i
this.hasPrePage = hasPrePage; GPLq$^AH
this.hasNextPage = hasNextPage; >A
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this.everyPage = everyPage; P{%R*hb]
this.totalPage = totalPage; )9s
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this.currentPage = currentPage; kcio]@#
this.beginIndex = beginIndex; ,l7',@6Y
} f,0,:)
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/** hjx=?
* @return T)tf!v3v
* Returns the beginIndex. K</="3
HK
*/ b|E1>TkY
publicint getBeginIndex(){ *7UDTgY
return beginIndex; -I*NS6
} % h"%G=:
o*Kl`3=]
/** .XPPd?R
* @param beginIndex c(r8
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* The beginIndex to set. eiwPp9[08
*/ y vo4 .u
publicvoid setBeginIndex(int beginIndex){ Xot2L{EIUE
this.beginIndex = beginIndex; +~f5dJyk`
} 1YJ@9 *l
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/** Q5>]f/LD
* @return B0$.oavC
* Returns the currentPage. k.Q4oyei
*/ 6y
publicint getCurrentPage(){ a
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return currentPage; _&}z+(Ug
} jrZH1dvE
f3"sKL4|
/** ?
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* @param currentPage dO|n[/qL0
* The currentPage to set. Q/ ^a(
*/ .qg 2zE$0
publicvoid setCurrentPage(int currentPage){ %w#8t#[,6
this.currentPage = currentPage; c'&\[b(m
} #B&%Y6E5
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/** v%!'vhf_K
* @return Hwiftx
* Returns the everyPage. #!R =h|
*/ 3iBUIv
publicint getEveryPage(){ 7]lUPLsl
return everyPage; *!&,)''
} J[jzkzSu`
#Pe|}!)u
/** I.hy"y2&
* @param everyPage B
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* The everyPage to set. |P(8T'
*/ j5V{,lf
publicvoid setEveryPage(int everyPage){ WdJJt2'
this.everyPage = everyPage; r>Cv@4/j
} . E?a
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/** |rwx;+
* @return 9M Ug/
* Returns the hasNextPage. p n(y4we
*/ 4StoEgFS
publicboolean getHasNextPage(){ ;$/]6@bqB
return hasNextPage; ^Q5advxuq
} 8 GW0w
#55_hY#
/** hL}AgY@
* @param hasNextPage z\+Ug9Of
* The hasNextPage to set. (;cvLop
*/ *TC#|5
publicvoid setHasNextPage(boolean hasNextPage){ h$$2(!G4
this.hasNextPage = hasNextPage; H rI(uZ]
} -mqL[ h,
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/** U}^`R,C
* @return w'zSV1
* Returns the hasPrePage. EKf! j3
*/ CQ/ps,~M
publicboolean getHasPrePage(){ %{ +>\0x
return hasPrePage;
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} {I]>!V0j!
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/** uow{a*qd6
* @param hasPrePage |ohCA&k%;
* The hasPrePage to set. v9XevLs
*/ Z^6qxZJ7
publicvoid setHasPrePage(boolean hasPrePage){ 33OkYC%e
this.hasPrePage = hasPrePage; ]3I@5 }5%
} m)e~HP7M
rB}2F*eT
/** ^C70b)68
* @return Returns the totalPage. mae@L
* Ob@HzXH
*/ n7(/ml+Q_
publicint getTotalPage(){ ?#Y1E~N
return totalPage; " mB
/"
} K-4o_:F
bD<hzOa
/** H-jxH,mJmW
* @param totalPage (Ky$(Ubb#6
* The totalPage to set. .'zcD^
*/ `[F[0fY-
publicvoid setTotalPage(int totalPage){ *Z2#U?_
this.totalPage = totalPage; +XpQ9Cd
} !MEA@^$#
cg_j.=M-
} rHJtNN8$k
(Z?g^kjq)
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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 uy8mhB+]
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个PageUtil,负责对Page对象进行构造: s(cC;
java代码: W
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/*Created on 2005-4-14*/ ; ~#uH7k
package org.flyware.util.page; k`NXYf:
:[?65q{
import org.apache.commons.logging.Log; |C}= 1
import org.apache.commons.logging.LogFactory; 8RjFp2)W
b/obHB+:
/** DMiB \o
* @author Joa B~47mw&b
* A+ LX37B
*/ h]DzX8r}
publicclass PageUtil { -~ H?R
/5m ~t.Z9M
privatestaticfinal Log logger = LogFactory.getLog ]BaK8mPl
|SuN3B4e
(PageUtil.class); l09SWug
<~n%=^knE
/** M s Q=1
* Use the origin page to create a new page `@^s}rt +
* @param page k FCdGl
* @param totalRecords yQE9S+%M
* @return YSux#*#H
*/ !XQ)>T^G5
publicstatic Page createPage(Page page, int *&tv(+P
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totalRecords){ ].
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return createPage(page.getEveryPage(), hFMT@Gy
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page.getCurrentPage(), totalRecords); Ah_0o_Di
} C~R,,
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/** HleMzykF
* the basic page utils not including exception Ti&v9re%wO
V?-SvQIk1
handler cXbQ
* @param everyPage nHl{'|~
* @param currentPage |[X-i["y
* @param totalRecords X1o=rT
* @return page 1ZO/R%[
*/ RuWu#tk
publicstatic Page createPage(int everyPage, int M i047-% (
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currentPage, int totalRecords){ qL~|bfN
everyPage = getEveryPage(everyPage); ZG8Xr"
currentPage = getCurrentPage(currentPage); b}J,&eYD
int beginIndex = getBeginIndex(everyPage, 4%5 +
k;Ask#rs
currentPage); ASUleOI79(
int totalPage = getTotalPage(everyPage, EM!9_8 f
>r.W \
totalRecords); VF:95F;@
boolean hasNextPage = hasNextPage(currentPage, 0X4I-xx#
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totalPage); .x][ _I>
boolean hasPrePage = hasPrePage(currentPage); l09DH+
i/RA/q
returnnew Page(hasPrePage, hasNextPage, Xp0S
everyPage, totalPage, 6-QcHJ>m6U
currentPage, r=S,/N(1
g)nT]+&
beginIndex);
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} r>g5_"FL
U
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privatestaticint getEveryPage(int everyPage){ b)7v-1N
return everyPage == 0 ? 10 : everyPage; (W5JVk_o
} eu0jjeB
*{dMo,.eI
privatestaticint getCurrentPage(int currentPage){ C=`MzZ bJ
return currentPage == 0 ? 1 : currentPage; ?Lbn R~/J
} V z-]H]MW,
[}`-KpV!;
privatestaticint getBeginIndex(int everyPage, int Dr5AJ`y9A
>\[| c
currentPage){ PLRMW2
return(currentPage - 1) * everyPage; }-~LXL%!3
} Rk!8eN Pf
vfdTGM`3
privatestaticint getTotalPage(int everyPage, int rY295Q
\nU_UH
totalRecords){ a LJ
d1Q
int totalPage = 0;
Ww=b{lUD
<jG[
z69)
if(totalRecords % everyPage == 0) [" sm7yQ
totalPage = totalRecords / everyPage; CvRO'
else Q-Oj%w4e
totalPage = totalRecords / everyPage + 1 ; _&aPF/
mb*|$ysPx
return totalPage; w+iIay
} E<\\/Q%w
6mV^akapv
privatestaticboolean hasPrePage(int currentPage){ </D )i
return currentPage == 1 ? false : true; _kdt0Vr,L
} ##nC@h@
3<_=Vyf
privatestaticboolean hasNextPage(int currentPage, GezMqt;2
Fb6d1I^wR
int totalPage){ X<&Y5\%F
return currentPage == totalPage || totalPage == d fSj= 4
+aN"*//i
0 ? false : true; {\gpXVrn_
} QypUBf
:D~J(Y2
j+("4b'
} PxA
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h}Lrp r2r
cVli^*se
Qcn;:6_&W
|IDZMd0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 L| ;WE=
.$o
A~
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 vURgR
Ho1 V)T>
做法如下: 8khIy-9-'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^O,r8K{1n
&Qq|
的信息,和一个结果集List: !\!j?z=O8
java代码: slaH 2}$xR
\-8aTF
j<)`|?@e(
/*Created on 2005-6-13*/ n?"("Fiw
package com.adt.bo; bu{dT8g'U
85lcd4&~
import java.util.List; q@1xYz:J
-_= m j
import org.flyware.util.page.Page; gBOF#"-
A=wG};%_
/** `><E J'h
* @author Joa Kl<NAv%j
*/ bnJ4Edy
publicclass Result { jZ''0Lclpc
HlEHk'
private Page page; @M"(
r"ab
3i~X`@$k>
private List content; b@O{e QB
dWdD^>8Ef
/** W}#n.c4+
* The default constructor sG\K$GP!
*/ <GF^VT|Ce
public Result(){ GJF &id
super(); M3r;Pdj2r
} eD7qc1*G
#q W#>0U
/** RT${7=
* The constructor using fields %m+7$iD
* zrf
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* @param page vmh>|N4a7
* @param content zRbY]dW
*/ _3.rPS,s
public Result(Page page, List content){ nLCaik_,m
this.page = page; )j\_*SoH
this.content = content; Ks<+@.DLTu
} k SgE_W)
lQEsa45
/** =T\=,B
* @return Returns the content. }kP<zvAaw
*/ (][-()YV
publicList getContent(){ x=+>J$~Pb
return content; xP/q[7>#Q
} G4&?O_\;
U`5/tNx
/** \>G}DGz
* @return Returns the page. t#3_M=L
*/ |* ^LsuFb
public Page getPage(){ [A~ Hl
return page; dMCoN8W
} E(vO^)#
@BG].UJo
/** `WnsM;1Y"
* @param content dFA1nn6{
* The content to set. sN2m?`?"G
*/ _,IjB/PR(
public void setContent(List content){ ib~i ^_p
this.content = content; lQBEq"7$
} PG}Roj
I
~X3x-nAt
/** v1Q78P
* @param page w`=O
'0d
* The page to set. r)OiiD"
*/ -/V(Z+dj
publicvoid setPage(Page page){ H5V>d
this.page = page; *C<;yPVc
} 3zu6#3^
} ,aa
4Kh
IN.g
;Rpib[m
3W]gn8
f*xr0l
2. 编写业务逻辑接口,并实现它(UserManager, :0QDV~bs
T\g+w\N
UserManagerImpl) CWocb=E
java代码: 3u& ,3:
GC' e
ir"t@"Y;o
/*Created on 2005-7-15*/ vhAgX0k
package com.adt.service; O ;[Mi
GM?s8yZ<
import net.sf.hibernate.HibernateException; aKWxL e
^g5E&0a`g
import org.flyware.util.page.Page; 0zkMRBe
{u2Zl7]z^
import com.adt.bo.Result; EmR82^_:
d~QM@<SV
/** w;j<$<4=7
* @author Joa >TY;l3ew
*/ MIn_?r
publicinterface UserManager { vSC1n8 /
cjJfxD&q
public Result listUser(Page page)throws +ima$a0Zyt
*YL86R+U
HibernateException; '4<o&b^yQ
%ut8/T
} |R _rfJh
ft1#f@b.
3Ovx)qKxd
n6+h;+8;]
T!ZjgCY}
java代码:
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(RV#piM
>}%#s`3W1_
/*Created on 2005-7-15*/ u!5q)>Wt(
package com.adt.service.impl; `[g$EXX
ES AX}uF
import java.util.List; 2xf lRks
ybw\^t
import net.sf.hibernate.HibernateException; pGjwI3_K
Yj/o17
import org.flyware.util.page.Page; 6]~/`6Dub
import org.flyware.util.page.PageUtil; \Ta5c31S+
PJ0~ymE1~G
import com.adt.bo.Result; ]% HxzJ
import com.adt.dao.UserDAO; q,O_y<uw
import com.adt.exception.ObjectNotFoundException; 4\u`MR
import com.adt.service.UserManager; yn_f%^!G
-0#"<!N
/** z!O;s
ep?/
* @author Joa 6V%}2YE?X
*/ r KUtTj
publicclass UserManagerImpl implements UserManager { 'jfE?ngt
d"06
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private UserDAO userDAO; \<*F#3U1
(${ #l
/** tWTHyL
* @param userDAO The userDAO to set. #~)A#~4O
*/ _.Hj:nFHz
publicvoid setUserDAO(UserDAO userDAO){ `;+x\0@<
this.userDAO = userDAO; Zk((VZ(y
} R20 .dA_N
G3io!XM)D
/* (non-Javadoc) /MY's&D(
* @see com.adt.service.UserManager#listUser vj%"x/TP
{$hWz (
(org.flyware.util.page.Page) nPdkvs
*/ i .uyfV&F
public Result listUser(Page page)throws q
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HibernateException, ObjectNotFoundException { $cHU,
int totalRecords = userDAO.getUserCount(); kY\faWuR
if(totalRecords == 0) Nh }-6|M
throw new ObjectNotFoundException ))f@9m
g:ky;-G8b
("userNotExist"); -0kMh.JYR
page = PageUtil.createPage(page, totalRecords); $q:l \
List users = userDAO.getUserByPage(page); G\dPGPPM
returnnew Result(page, users); #p>&|I
} K~,!IU_QG
J<"K`|F
} 5>.ATfAsV
<<u]WsW{C
QUn!&55
m;l[flQ~
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jY1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 npltsK):
4 H0rS'5d
询,接下来编写UserDAO的代码:
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3. UserDAO 和 UserDAOImpl: syW[uXNLZ
java代码: x5uz$g
X^N6s"2
J FnE{
/*Created on 2005-7-15*/ ocWl]h].
package com.adt.dao; @2h hB W
>IrQhSF
import java.util.List; 7;q0'_G
eLPtdP5k
import org.flyware.util.page.Page; O=7S=Rm4&
3WF]%P%
import net.sf.hibernate.HibernateException; =Pw{1m|k
$I*}AUp
v?
/** #X'-/q`.
* @author Joa Ve%ua]qA
*/ U<0Wa>3zj
publicinterface UserDAO extends BaseDAO { 8(Te^] v#
xaVX@ 3r.3
publicList getUserByName(String name)throws Kt*fQ
`9
/ ^d9At614
HibernateException; ^6kl4:{idE
<M1*gz
publicint getUserCount()throws HibernateException; _lk VT']
0SYJ*7lPX
publicList getUserByPage(Page page)throws 2~f*o^%l
KPO w
HibernateException; /kG?I_z
rtz-kQ38R
} X,l7>>L{g
xbhHP2F|
=@M9S
b'+Wf#.]f0
C]mp<
java代码: i=#\`"/
-@>]iBl
|e@1@q(a[]
/*Created on 2005-7-15*/ Q2ne]MI
package com.adt.dao.impl; k{;?>=FH!
mz.,j(Ks-
import java.util.List; m<3. X"-
2QbKh)
import org.flyware.util.page.Page; w:%NEa,Z
wsB-(
0-
import net.sf.hibernate.HibernateException; {l$)X
import net.sf.hibernate.Query; A4@z+ebb l
zqdkt `
import com.adt.dao.UserDAO; 4'#=_J
a. D cmy{
/** W?zj^y[w
* @author Joa ZrEou}z(*
*/ 153*b^iDBh
public class UserDAOImpl extends BaseDAOHibernateImpl 18%$Z$K,
A,EG0yb
implements UserDAO { n$SL"iezW?
bS8$[7OhX
/* (non-Javadoc) 7=fNvES2
* @see com.adt.dao.UserDAO#getUserByName liPrxuP`
L@[}sMdq(
(java.lang.String) V)~b+D
*/ Z1q<) O1QX
publicList getUserByName(String name)throws !%t@wQ]\hG
`;}qjm0a
HibernateException { nw/g[/<;
String querySentence = "FROM user in class Zc_F"KJL
vo
}4N[]Sb
com.adt.po.User WHERE user.name=:name"; Kn$E{ F\
Query query = getSession().createQuery <`SA>P
83V\O_7j
(querySentence); #pAN
query.setParameter("name", name); 81|[Y'f
return query.list(); kK}?NKqT
} B^TgEr
I/St=-;
/* (non-Javadoc) x'}zNEXI
* @see com.adt.dao.UserDAO#getUserCount() K{I "2c
*/ 5Xxdm-0
publicint getUserCount()throws HibernateException { :dbO|]Xf
int count = 0; <ndY6n3
String querySentence = "SELECT count(*) FROM J)Yz@0#T(;
jNX6Ct?
user in class com.adt.po.User"; 8~,zv_Pl
Query query = getSession().createQuery 09vVCM;DY
a+v.(mCG
(querySentence); sSKD"
count = ((Integer)query.iterate().next )UU`uzU;u
B=W#eu
<1
()).intValue(); 3'L =S
return count; :dipk,b?n
} mm#UaEp
|4/rVj"
/* (non-Javadoc) :yJ#yad
* @see com.adt.dao.UserDAO#getUserByPage 3<)][<Ud
(bI/s'?K
(org.flyware.util.page.Page) w8q
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*/ F#9^RA)9
publicList getUserByPage(Page page)throws ZGh6- /
;>ml@@Z
HibernateException { b (HJ|
String querySentence = "FROM user in class wGs'qL"z
_M8'~$Sg
com.adt.po.User"; EVqqOp1$v4
Query query = getSession().createQuery au=@]n#<(
W^HE1Dt]
(querySentence); a|y'-r90
query.setFirstResult(page.getBeginIndex()) #G(ivRo
.setMaxResults(page.getEveryPage()); EY !o#m
return query.list(); l2M(
} u"7!EhX&
L^CB#5uG
} Y<Ae_yLa
mmjWLrhlu
L"1AC&~u
_
j'm2BAO
"usPzp5
至此,一个完整的分页程序完成。前台的只需要调用 >f&L7@
;=P!fvHk
userManager.listUser(page)即可得到一个Page对象和结果集对象 D{d%*hlI 3
(O!CHN!:
的综合体,而传入的参数page对象则可以由前台传入,如果用 &%(Dd
`N}Vi6FG
webwork,甚至可以直接在配置文件中指定。 QaE!?R
(8ct'Q ;
下面给出一个webwork调用示例: )JyB
java代码: ~S~+'V,d
@v&P;=lU
ryzNM3
/*Created on 2005-6-17*/ iSOyp\E|
package com.adt.action.user; _XT;
2Gj)fMK38
import java.util.List; 4,YL15.
R $dNdd9m
import org.apache.commons.logging.Log; q3v5gz^t
import org.apache.commons.logging.LogFactory; ntPX?/
import org.flyware.util.page.Page; N2j^fZd_
WCqa[=v)t
import com.adt.bo.Result; _ A{F2M
import com.adt.service.UserService; <7Yh<(R e^
import com.opensymphony.xwork.Action; 9RSviIi$
EcytNYn
/** k=p[Mlic/
* @author Joa t5 ^hZZ
*/ rR{KnM
publicclass ListUser implementsAction{ CO,{/
B )\;Ja
privatestaticfinal Log logger = LogFactory.getLog q TWQ!
Ur1kb{i
(ListUser.class); }{PG^ Fc<P
icVB?M,m
private UserService userService; >bmdu\j5R
b,jo94.G
private Page page; ]M "U 'Z
^HuB40
privateList users; 4kV$JV.l
(t@!0_5
/* e `JWY9%
* (non-Javadoc) [ gR,nJH.
* eMn'z]M&]
* @see com.opensymphony.xwork.Action#execute() PN J&{4wY
*/ HHgv,bC!
publicString execute()throwsException{ # Rs5W
Result result = userService.listUser(page); .*+jD^Gr
page = result.getPage(); T~XKV`LQ
users = result.getContent(); 3)e{{]6
return SUCCESS; kQ2WdpZ/
}
noB8*n0
0Q#}:
/** i&)([C0z$
* @return Returns the page. V+U89j1g
*/ Wi\k&V.mE
public Page getPage(){ Y>8JHoV
return page; heWQPM|s
} Ix(,gDN
|,H2ge
/** ?-0, x|ul
* @return Returns the users. E 8$S0u;`
*/ y5^OD63s
publicList getUsers(){ &b%2Jx[+
return users; {C8IYBm
} pP"j|
8aM\B%NGWi
/** p*1B*R
* @param page R S>qP;V*-
* The page to set. 4OAR ["f
*/ O^ &m
publicvoid setPage(Page page){ =jxy4`oF
this.page = page; "|,KXv')
} w|0:0Rc~u
"HH<5M
/** !`W0;0'Zg
* @param users {+Wknm%
* The users to set. oxI?7dy5
*/ 7GErh,
publicvoid setUsers(List users){ `6# s+JA[
this.users = users; VH+3o?nrT
} 1TGE>HG
BT$Oh4y4
/** 3U!=R-
* @param userService |S<!'rY
* The userService to set. gg#lI|
*/ ~oK0k_{~
publicvoid setUserService(UserService userService){ g2M1zRm;
this.userService = userService; zqQ[uO]m?
} )>"Ky
} s bR*[2
.SSyW{a3w
|]Hr"saO0
ug"4P.wI
)7#3n(_np
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, N
K@6U_/W
TnKOr~ @*
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 hOFvM&$
>r}?v3QW
么只需要: }!|$;3t+c
java代码: >@-.rkd(
J!3;\
hl)jE
06
<?xml version="1.0"?> uc]5p(9Hb
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork d6??OO=~>M
Z>X]'q03
1.0//EN" "http://www.opensymphony.com/xwork/xwork- F,K))325
\F+".X#jh
1.0.dtd"> Ul 85-p
/L|x3RHs
<xwork> TT#V'r\
376z~
<package name="user" extends="webwork- lh XD9ed
Tfv@oPu
interceptors"> p u?COA
}w>UNGUMh
<!-- The default interceptor stack name $
)2zz>4
SD@ 0X[
--> ?=-/5A4K
<default-interceptor-ref y4=T0[
V
F8/n;
name="myDefaultWebStack"/> Qs8yJH`v
@$%.iQ7A;
<action name="listUser" VyNU<}
Es\J%*\u
class="com.adt.action.user.ListUser"> DPmY_[OAE
<param .vi0DuD6
^4Se=Hr
z2
name="page.everyPage">10</param> qa8?bNd'f
<result fgF@ x
/V]i3ac
name="success">/user/user_list.jsp</result> p=i6~
</action> Xw|-v$'y
_,e4?grP#
</package>
Z}SqiT
o,0
Z^"|
</xwork> _oefp*iWS
D+q z`
$kkL)O*"]
r5$!41
{FILt3f;
G"Ey%Q2K
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 /,$V/q+
%* gg6Q
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 |'x"+x
muFWFq&yP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iHQ$L# 7
Z;0<k;#T(p
t9lf=+%s
<1_3`t
qn}VW0!
我写的一个用于分页的类,用了泛型了,hoho iVmy|ewd
8R(l~
java代码: i;IhsKO0R
Nm%#rZrN~Q
66_=bd(9
package com.intokr.util; |X6R2I
Rz*GRe
import java.util.List; 6 lEv<)cC
vuJEPn%
/** AOV{@b(
* 用于分页的类<br> _?I*::
I
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 34_
V&8
* 7lwFxP5QT
* @version 0.01 ) <w`:wD
* @author cheng <w?k<%( 4
*/ 2l:cP2fa
public class Paginator<E> { 6UqDpL7^U
privateint count = 0; // 总记录数 cveQ6
-`K
privateint p = 1; // 页编号 *Aug7
HlS
privateint num = 20; // 每页的记录数 p^ OHLT
privateList<E> results = null; // 结果 N'pYz0_H
+4[9Eb'k=
/** ]-;JHB5A_:
* 结果总数 zq3f@xOK
*/ pXA|'U5]
publicint getCount(){ $uRi/%Q9
return count; [.CP,Ly
} -<" ;|v4
3&+nV1
publicvoid setCount(int count){ 'Ddzlip
this.count = count; hyhm{RC?[
} lB#7j
5as5{"l
/** 'cc{sjG
* 本结果所在的页码,从1开始 Np$ue
}yr
* l2Rnyb<;;
* @return Returns the pageNo. it-2]Nw
*/ E!L_"GW
publicint getP(){ J5xZLv
return p; T~g`;Q%i
} xjrL@LO#
1/?K/gL
/** rcH{"\F_/
* if(p<=0) p=1 >>8{N)c5E
* ?<Mx* l
* @param p nm%7 e!{m
*/ Re*~C:
publicvoid setP(int p){ 4 DV,f2:R4
if(p <= 0) K7i@7
p = 1; 2dbn~j0
this.p = p; J
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} Gj[5ew?@
k_gl$`A
/** 79h'sp6;
* 每页记录数量 [N"=rY4G
*/ ph%t
#R
publicint getNum(){ M.EL^;r
return num; nD!t*P
} K @:t6
]xbMMax
/** ]A1'+!1$
* if(num<1) num=1 u4 ~.[3E*
*/ kD)]\
publicvoid setNum(int num){ )Z\Zw~L
if(num < 1) /2tPd
num = 1; J?hs\nA
this.num = num; -q&,7'V
} ,F "P/`i'
Wo,93]
/** 0 ;4 YU%u
* 获得总页数 nu2m5RYx
*/ >q ,Z*s>?
publicint getPageNum(){ "x
3C3Zu.;
return(count - 1) / num + 1; *,=8x\Shp
} 9j5-/
3[ xHY@c
/** ^nDa-J$
* 获得本页的开始编号,为 (p-1)*num+1 53^3..E|
*/ 7d+0'3%
publicint getStart(){ >Qg-dJt[
return(p - 1) * num + 1; <KI>:@|Sc
} :EH>&vm
us.IdG
/** :X}Ie P
* @return Returns the results. bwJluJ,E
*/ 0+.<BOcW5
publicList<E> getResults(){ Xc~BHEp
return results; n_wF_K\h
} 7c6-
o"A
)lJi7 ^,
public void setResults(List<E> results){ ]c]^(C
this.results = results; 3/]~#y%2
} _p^Wc.[~M
_!w69>Nj
public String toString(){ 9Q7342
StringBuilder buff = new StringBuilder Zvra > %
u EERNo&
(); bHXoZix
buff.append("{"); w U1[/
buff.append("count:").append(count); XK;Vu#E*^
buff.append(",p:").append(p); Mh{;1$j#
buff.append(",nump:").append(num); i8%@4U/ J
buff.append(",results:").append sI{?4k
:%+9y @%
(results); V=YDqof
buff.append("}"); gN*b~&G
return buff.toString(); {xICR ~,*
} rMw$T=Oi
k"m+i
} t%@u)b p
Zb'a+8[
H;ujB \+