Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,%9XG077
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UdO8KD#r3
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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 e@h{Ns.1-
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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 xGsOnY;
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分页支持类: %],BgLhS.
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java代码: ?IGp?R^j"
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package com.javaeye.common.util; lD0p=`.
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import java.util.List; P#A,(Bke3
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publicclass PaginationSupport { I 1]YT
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publicfinalstaticint PAGESIZE = 30; 7\UHADr
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privateint pageSize = PAGESIZE; 1GN^uia7
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privateList items; &y_t,8>5
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privateint totalCount; 8-G )lyfj
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privateint[] indexes = newint[0]; =Z+^n
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privateint startIndex = 0; !~E/Rp
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public PaginationSupport(List items, int ]xvA2!)Q
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totalCount){ .F ?ww}2p]
setPageSize(PAGESIZE); /g u
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setTotalCount(totalCount); "(mJupI
setItems(items); I"x'
setStartIndex(0); *8)?ZZMM
} C1-U2@
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public PaginationSupport(List items, int 5X0ex.
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totalCount, int startIndex){ K\-N'M!Z
setPageSize(PAGESIZE); v6)QLp
setTotalCount(totalCount); xsZN@hT
setItems(items); ?w/p 9j#
setStartIndex(startIndex); |lLe^FM
} a#1r'z~]}
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public PaginationSupport(List items, int KF7w{A){
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totalCount, int pageSize, int startIndex){ va@;V+cD
setPageSize(pageSize); ;W{z"L;nX
setTotalCount(totalCount); 5j`sJvq
setItems(items); 8$-MUF,
setStartIndex(startIndex); 6Jgl"Jw8
} j"jssbu}
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publicList getItems(){ JlSqTfA
return items; yD<#Q\,
} 2[B bdg[O
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publicvoid setItems(List items){ `)O9
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this.items = items; N~|f^#L
} q;AD#A|\
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publicint getPageSize(){ Y's=31G@
return pageSize; }P2*MrkcHB
} 0-p^ oA
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publicvoid setPageSize(int pageSize){ lz=DGm
this.pageSize = pageSize; 1
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} "pt[Nm76)8
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publicint getTotalCount(){ pRfKlTU\
return totalCount; UusAsezm:
} VsA_x
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publicvoid setTotalCount(int totalCount){ ]Z[3 \~?
if(totalCount > 0){ ULew ~j
this.totalCount = totalCount; U$D:gZ
int count = totalCount / *`OXgkQ
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pageSize; !o|
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if(totalCount % pageSize > 0) 86%k2~L
count++; q!&:y7O8
indexes = newint[count]; N_D=j6B
for(int i = 0; i < count; i++){ }*XF- U
indexes = pageSize * mTH[*Y,
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} e`+
}else{ 6 w!qZ4$
this.totalCount = 0; ="T}mc
} -)J*(7F(6^
} tDAX
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publicint[] getIndexes(){ W[QgddR
return indexes; tQj=m_
} !o'a]8
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publicvoid setIndexes(int[] indexes){ +4t
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this.indexes = indexes; U-?r>K2
} LZ#A`&qUd
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publicint getStartIndex(){ i_L u
return startIndex; GF9iK|i/
} iMVQt1/
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publicvoid setStartIndex(int startIndex){ e>Q:j_?.e
if(totalCount <= 0) PJb/tKC
this.startIndex = 0; f:q2JgX
elseif(startIndex >= totalCount) \ bNDeA&l
this.startIndex = indexes zV$Z@o
@ &c@
[indexes.length - 1]; !/2kJOSp
elseif(startIndex < 0) (N}\Wft%
this.startIndex = 0; 2P57C;N8|
else{ 7T X$
this.startIndex = indexes Q-_;.xy#4
a&)$s;
[startIndex / pageSize]; !G;BYr>X
} OG IN-
} 0Q%I[f8
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publicint getNextIndex(){ 0NsPo
int nextIndex = getStartIndex() + )$Fw<;4
@6 jKjI
pageSize; ;).QhHeg>
if(nextIndex >= totalCount) On4Vqbks
return getStartIndex(); 09Oe-Bg
else Xa8_kv_
return nextIndex; @)ozgs@e
} Wbmqf
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publicint getPreviousIndex(){ f$nZogaQ
int previousIndex = getStartIndex() - I~
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pageSize; AxJf\B8
if(previousIndex < 0) eF8um$t9
return0; bB.nevb9p
else =Oh/4TbW[
return previousIndex; Y$q--JA
} K<ldl.
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} P`hg*"<V
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抽象业务类 BGB.SN#q+
java代码: RV5;EM)~[
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/** 6mrfkYK
* Created on 2005-7-12 )N
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*/ {7Ez7'SVV
package com.javaeye.common.business; ctC!b{S"@
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import java.io.Serializable; ~o;*{ Q
import java.util.List; YF");itH
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import org.hibernate.Criteria; n@e|PWu
import org.hibernate.HibernateException; $/i;UUd
import org.hibernate.Session; doe u`
import org.hibernate.criterion.DetachedCriteria; ( (mNB]sy
import org.hibernate.criterion.Projections; ;#D:S6 L
import %}~Ncn_r
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org.springframework.orm.hibernate3.HibernateCallback; ]\R%@FCYc
import [k
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org.springframework.orm.hibernate3.support.HibernateDaoS bO{wQ1)Z_
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upport; ;@u+b0
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import com.javaeye.common.util.PaginationSupport; PsMCs|*
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public abstract class AbstractManager extends nIP*yb}5
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HibernateDaoSupport { tO QY./I
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privateboolean cacheQueries = false; tTrue?
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privateString queryCacheRegion; Q[F$6m%o
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publicvoid setCacheQueries(boolean w0t||qj^>"
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cacheQueries){ ;lo!o9`<
this.cacheQueries = cacheQueries; [318Q%W&
} w+owx(mN@
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publicvoid setQueryCacheRegion(String X6@G)68
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queryCacheRegion){ E>SLR8!Cv
this.queryCacheRegion = PM%Gsy]q
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queryCacheRegion; Yf(QU`w_
} Go_~8w0<
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publicvoid save(finalObject entity){ DbkKmv&
getHibernateTemplate().save(entity); %,*{hhfu
} /e}NZo{)g
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publicvoid persist(finalObject entity){ [&
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getHibernateTemplate().save(entity); P\CT|K'P
} RoWGQney
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publicvoid update(finalObject entity){ h{cJ S9e}
getHibernateTemplate().update(entity); toCT5E_0=
} t1YVE%`w
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publicvoid delete(finalObject entity){ 'e>0*hF[
getHibernateTemplate().delete(entity); ]T! >]
} }A`4ae=
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publicObject load(finalClass entity, 3 tp'}v
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finalSerializable id){ {aWTT&-N
return getHibernateTemplate().load q>*+.~
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(entity, id); 5}4r'P$m:
} 0xM\+R~,
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publicObject get(finalClass entity, I vQ]-A}N
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finalSerializable id){ (TV ye4Z
return getHibernateTemplate().get ,$96bF "#
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(entity, id); QuJ)WaJkC
} O?9&6x
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publicList findAll(finalClass entity){ Vn6 g(:\w
return getHibernateTemplate().find("from b}9Ry"
jR#g>MDKB
" + entity.getName()); Q!:J.J
} X99:/3MXB'
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publicList findByNamedQuery(finalString ~ b;%J:
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namedQuery){ g,!6,v@
return getHibernateTemplate Uzb~L_\Rmt
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().findByNamedQuery(namedQuery); &C+pen)Z
} shOQ/
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publicList findByNamedQuery(finalString query, hSq3LoHV
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finalObject parameter){ !K#Q[Ee
return getHibernateTemplate Q0I22?
d([NU;
().findByNamedQuery(query, parameter); 8=H!&+aGh
} 7Xi)[M?)#
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publicList findByNamedQuery(finalString query, D}wM$B@S
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finalObject[] parameters){ `Li3=!V[
return getHibernateTemplate t3.;W/0_
aCe<*;b@
().findByNamedQuery(query, parameters); O<Rm9tZ8
} W|o LS
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publicList find(finalString query){ i:wTPR
return getHibernateTemplate().find vl8Ums} +
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(query); yT<yy>J9l#
} 18 pi3i[
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publicList find(finalString query, finalObject :yo tpa
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parameter){ x8xSA*@k
return getHibernateTemplate().find G%w hOIFRq
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(query, parameter); .V9/0
} j()<.h;'
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public PaginationSupport findPageByCriteria ;#G)([
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(final DetachedCriteria detachedCriteria){ .olDmFQD
return findPageByCriteria TOp|Qtn
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r7r>1W%4
} IPK.
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public PaginationSupport findPageByCriteria s_A<bW566F
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(final DetachedCriteria detachedCriteria, finalint ,rT62w*e
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startIndex){ !j,LS$tPu
return findPageByCriteria #;?j]npg]
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(detachedCriteria, PaginationSupport.PAGESIZE, y~CK&[H
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startIndex); $IzhaX
} fGDR<t3yiQ
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public PaginationSupport findPageByCriteria a%a_sR\)
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(final DetachedCriteria detachedCriteria, finalint =Jd('r
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pageSize, FMCX->}$
finalint startIndex){ Gj[`r
return(PaginationSupport) vs-%J6}G
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getHibernateTemplate().execute(new HibernateCallback(){ N6Mo|
publicObject doInHibernate :uE:mY%R
#'N"<o[
(Session session)throws HibernateException { RHc63b\
Criteria criteria = w,fA-*bZ 0
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detachedCriteria.getExecutableCriteria(session); pJ Iq`)p5
int totalCount = M8oCh
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((Integer) criteria.setProjection(Projections.rowCount !e?g"5r{Bv
],l
w
()).uniqueResult()).intValue(); n4Od4&r
criteria.setProjection E^z\b *
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(null); >h+[#3vD
List items = K]4XD1n7
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criteria.setFirstResult(startIndex).setMaxResults RN(>37B3_
TxL;qZRY
^
(pageSize).list(); ;fLYO6
PaginationSupport ps = x_&=IyU0j
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new PaginationSupport(items, totalCount, pageSize, -F.A1{l[.
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startIndex); ))Ws{
return ps; 0J-]
} {kGcZf3h
}, true); 69#D,ME?
} n\8;4]n
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public List findAllByCriteria(final GORu*[U8
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DetachedCriteria detachedCriteria){ egcJ@Of
return(List) getHibernateTemplate 2%Bq[SMuN
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().execute(new HibernateCallback(){ aChyl;#E
publicObject doInHibernate am>X7
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(Session session)throws HibernateException { $2u^z=`b!%
Criteria criteria = HP T{83
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detachedCriteria.getExecutableCriteria(session); IR; DdF
return criteria.list(); ^fVLM>p <;
} N|cWTbi
}, true); >_3+s~
} 1<Fh
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public int getCountByCriteria(final wfr+-
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DetachedCriteria detachedCriteria){ kkfwICBI
Integer count = (Integer) Q2[@yRY/z
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getHibernateTemplate().execute(new HibernateCallback(){ So &c\Ff
publicObject doInHibernate T8|aFoHCK
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(Session session)throws HibernateException { N<bNJD}
Criteria criteria = Pe_mX*0
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detachedCriteria.getExecutableCriteria(session); ub^v,S8O
return 3m1]Ia-9
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criteria.setProjection(Projections.rowCount P} =eR
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()).uniqueResult(); a o_A%?Ld
} lLD-QO}/
}, true); nNe`?TS?f
return count.intValue(); B{IYVviiP
} 7gIK+1`
} C~\/FrO?
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用户在web层构造查询条件detachedCriteria,和可选的 }T!2IaAB
AEx|<E0
startIndex,调用业务bean的相应findByCriteria方法,返回一个 UPtWj8h
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PaginationSupport的实例ps。 _H#l&bL@C
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ps.getItems()得到已分页好的结果集 cI #2MjL
ps.getIndexes()得到分页索引的数组 |E+tQQr%'
ps.getTotalCount()得到总结果数 v] *(Wd~|
ps.getStartIndex()当前分页索引 *h ~Y=#`8*
ps.getNextIndex()下一页索引 VKa-
ps.getPreviousIndex()上一页索引 ,,+ ~./)
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 D}Jhg`9
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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 %\=oy=f
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一下代码重构了。 9T*%CI
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类: 7h?yAgDv~
java代码: p{:r4!*L
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/*Created on 2005-4-14*/ $"Oy }
package org.flyware.util.page; ;]<{<czc
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/** [ e4)"A"
* @author Joa !x9j~D'C`
* #k%3Ag
*/ )2Gp3oD?
publicclass Page { a7G0
gIA{6,A
/** imply if the page has previous page */ c"+N{$ vp
privateboolean hasPrePage; +~ro*{3
Yuy7TeJRx
/** imply if the page has next page */ rQNT
privateboolean hasNextPage; m,nV,}@J
Y=3:Q%X
/** the number of every page */ "4FL<6
privateint everyPage; [P*3ld,,G%
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/** the total page number */ `~( P
privateint totalPage; kmM4KP#&|
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/** the number of current page */ b~ ?TDm7
privateint currentPage; R6 wK'
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/** the begin index of the records by the current ~Z5?\a2Ld
OT7F#:2`
query */ z`uqK!v(K
privateint beginIndex; 1Oo^
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/** The default constructor */ &?3?8Q\
public Page(){ EmNB}\IYU
+P6#7.p`Z
} v>Il#
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/** construct the page by everyPage ZNPzQ:I@
* @param everyPage x_Ki5~w5
* */ :=04_5 z
public Page(int everyPage){ 8eP2B281
this.everyPage = everyPage; xJ9_#$ngeM
} Ms?V1
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/** The whole constructor */ S[UHx}.
public Page(boolean hasPrePage, boolean hasNextPage, {Ny\9r
&)Z8Qu
yz-IZt(
int everyPage, int totalPage, sZ-]yr\E"
int currentPage, int beginIndex){ =S@$"_&
this.hasPrePage = hasPrePage; kP%W:4l0
this.hasNextPage = hasNextPage; vII&v+C
this.everyPage = everyPage; U-TwrX
this.totalPage = totalPage; H<`[,t
this.currentPage = currentPage; UQ>GAzh
this.beginIndex = beginIndex; <W,k$|w
} w;Qo9=-
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/** 8 Oeg"d
* @return TMG:fg&E~
* Returns the beginIndex. xy$FS0u
*/ Xvs{2
publicint getBeginIndex(){ 5fb,-`m.
return beginIndex; ]^gD@].
} }M/w 0U0o
n:he`7.6O
/** tH:ea$A
* @param beginIndex #s1M>M)
* The beginIndex to set. ;JFE7\-mC
*/ NpD}7t<EF
publicvoid setBeginIndex(int beginIndex){ GT%V,OJ
this.beginIndex = beginIndex; MvY0?!v
} U=XaI%ZM)
*D<S \6=
/** P0Na<)\'Y!
* @return !N,Z3p>Q
* Returns the currentPage. 5 LX3.
*/ z$G?J+?J
publicint getCurrentPage(){ p%IR4f
return currentPage; 1:7>Em<s
} D4'?
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/** 0P/A
* @param currentPage O(
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* The currentPage to set. ~B(]0:
*/ d5A!kU _.
publicvoid setCurrentPage(int currentPage){ EhB9M!Y`@
this.currentPage = currentPage; QY+#Vp<`
} #2ZXYH}
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/** F.A<e #e?
* @return ^&&dO*0{
* Returns the everyPage. g) v"nNS
*/ n{BC m %
publicint getEveryPage(){ ejo4mQ]a
return everyPage; |@nvg>mu
} e+y< a~N
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/** 8kJ k5
* @param everyPage @hzQk~Gdi
* The everyPage to set. H.idL6*G
*/ P+}qaup
publicvoid setEveryPage(int everyPage){ q'(WIv@
this.everyPage = everyPage; !+uMH!
} #EHBS~^
qoZ* sV
/** 6j"(/X|Ex5
* @return +8^9:w0}
* Returns the hasNextPage. [=U7V;5($
*/ 20?i4h_
publicboolean getHasNextPage(){ =_":Z!_
return hasNextPage; V2 VsJ
} h!K
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I J4"X#Q/
/**
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* @param hasNextPage f{AgKW9"
* The hasNextPage to set. ,dVCbAS@
*/ (la<X<w
publicvoid setHasNextPage(boolean hasNextPage){ hsqUiB tc6
this.hasNextPage = hasNextPage; W$'pUhq\H
} C9=f=sGL
J $e.$ah;
/** K,IOD
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* @return $,aU"'D
* Returns the hasPrePage. =R>Sxaq
*/ yQi|^X~?$
publicboolean getHasPrePage(){ p1?}"bHk
return hasPrePage; 3~cOQ%#]4
} ,j_{IL690
&us8,x6yg
/** _5`M( ;hL2
* @param hasPrePage Ep?a>\
* The hasPrePage to set. "~V}MPt
*/ B4|`Z'U#;
publicvoid setHasPrePage(boolean hasPrePage){ HO@T2t[
this.hasPrePage = hasPrePage; V)@MM2,
} QK? 5)[ J
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/** a^=4'.ok
* @return Returns the totalPage. l4/TJ%`MG
* `|/|ej]$P
*/ "^XN"SUw
publicint getTotalPage(){ Q}=RG//0*
return totalPage; 3Aj_,&X.@(
} c%Gz{':+
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/** '^/E2+
* @param totalPage Bw_Ih|y,w
* The totalPage to set. &)X<yd0
*/ <rC#1wR4
publicvoid setTotalPage(int totalPage){ wP8R=T
this.totalPage = totalPage; L}21[ N~ky
} &R5M&IwL
3?O|X+$p
} :?UIyN?
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9~; Ju^b
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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 /7lkbL
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个PageUtil,负责对Page对象进行构造: N )!v-z,k
java代码: I!(yU
;
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/*Created on 2005-4-14*/ ,Tz
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package org.flyware.util.page; u}:O[DG
XBY"7}
import org.apache.commons.logging.Log; h7y*2:l6
import org.apache.commons.logging.LogFactory; YSwD#jO0
N|~&Q!A&
/**
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* @author Joa \6'A^cE/PX
* ib&qH_r/
*/ u]2k %TUY
publicclass PageUtil { [.Y=~)7FB
ho20>vw#
privatestaticfinal Log logger = LogFactory.getLog =
]@xXVf/
)/ZSb1!
(PageUtil.class); UF%5/SiVX
3LxJ}>]TO
/** }O>Zu[8a
* Use the origin page to create a new page 2"MI8EK
* @param page Orb(xLChJ
* @param totalRecords kp6x6%{K\
* @return M[{Cy[ta
*/ 7_3O]e[8
publicstatic Page createPage(Page page, int "J.jmR;
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totalRecords){ -J30g\
return createPage(page.getEveryPage(), FGH>;H@
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page.getCurrentPage(), totalRecords); 6~8
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} *]eZ Y
q
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/** "pPNlV]UA^
* the basic page utils not including exception ye%F <:O7
e)xWQ=,C
handler 2)A
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* @param everyPage 4eEs_R
* @param currentPage &\H5*A.HkA
* @param totalRecords ]03ZrZ!
PM
* @return page cR&xl^BJ
*/ KwHOV$lD;
publicstatic Page createPage(int everyPage, int G8s`<:9*
0/6&2
currentPage, int totalRecords){ +o3g]0
everyPage = getEveryPage(everyPage); z3C^L
currentPage = getCurrentPage(currentPage); ul?BKV+3E
int beginIndex = getBeginIndex(everyPage, qLP+@wbJ
=c,gK8C
currentPage); vck$@3*
int totalPage = getTotalPage(everyPage, )
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3XnXQ/({
totalRecords); $"8k|^Z3
boolean hasNextPage = hasNextPage(currentPage, &rl>{Uvq
$Y`aS^IW
totalPage); U.aa iX7
boolean hasPrePage = hasPrePage(currentPage); *X\c
$=*
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returnnew Page(hasPrePage, hasNextPage, `Ek !;u>
everyPage, totalPage, KVR}Tp/R
currentPage, )^\='(s
!{Y#<tG]
beginIndex); fh_
.J[Y.k
} kOCxIJ!Xp=
/pU6trIM
privatestaticint getEveryPage(int everyPage){ (M+<^3c
return everyPage == 0 ? 10 : everyPage; \uk #pL
} 9^^#I~-
W~%~^2g ;k
privatestaticint getCurrentPage(int currentPage){ 5u46Vl{
return currentPage == 0 ? 1 : currentPage; JY2
F-0t)
} j''Iai_
?iX=2-
privatestaticint getBeginIndex(int everyPage, int /;rN/ot2o
32iI :u
currentPage){ JF*g!sV%
return(currentPage - 1) * everyPage; >, E$bm2
}
9+QrTO
5E!m! nBZ
privatestaticint getTotalPage(int everyPage, int B`scuLl3
Zir`IQ$
totalRecords){ SR&
mHI-f0
int totalPage = 0; Gme$FWa
zy[=OX+
if(totalRecords % everyPage == 0) 9i}D6te
totalPage = totalRecords / everyPage; (U_Q7hja?
else FIjET1{
totalPage = totalRecords / everyPage + 1 ; #mhD; .Wg
Qs9 U&*L
return totalPage; rk/
c
} mi<D
bnou
\+3Wd$I
privatestaticboolean hasPrePage(int currentPage){ -o_TC
return currentPage == 1 ? false : true; &=Zg0Q
} />Vx*^u8Hz
}4]<P
privatestaticboolean hasNextPage(int currentPage, ZZU 8B?)
#(
sNk,^Ax
int totalPage){ S;Z3v)E-f
return currentPage == totalPage || totalPage == K$cIVsfr
{p|%hhTK%
0 ? false : true; 50ew/fZj|
} aNC,ccm
:bRR(sP
Kk>qgi$
} 5\0.[W{^
=Rx?6%
J,G9m4Z7
{7Avba
P! Ed
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。 /iy*3P,`
c^Jgr(Ow
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 0@K:Tq-mF
m"(d%N7
做法如下: {[5L96RH%
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 SP*JleQN
'ZH<g8:=@
的信息,和一个结果集List: iM|"H..
java代码: nRB>[lG
4l}M
i
N>fYH.c3Y
/*Created on 2005-6-13*/ 1m`tqlFU9
package com.adt.bo; 7~ese+\smG
DRW.NL o
import java.util.List; sV^h#g~Zb
p/1}>F|i
import org.flyware.util.page.Page; 9G&l qfX:
y3nm!tjyM
/** C^" Hj
* @author Joa O)xEF~DaD
*/ 6IY}SI0N
publicclass Result { <
mK
'?G[T28
private Page page; ,(0XsBL
[k~+(.2I
private List content; ]Ec[")"kT
=x0"6gTz>
/** !@Sf>DM"
* The default constructor r\n
h.}s
*/ VuMDV6^Z
public Result(){ sRyw\v-=P
super(); sIRrEea
} vvsNWA
6G<Hi"I
/** Cre0e$ a
* The constructor using fields mU+FQX
* oiv2rOFu
* @param page 8<-oJs_o+
* @param content ;2Ad])
*/ ju^"vw
public Result(Page page, List content){ 5Vqmv<F;$Z
this.page = page; *[xNp[4EU
this.content = content; ;WS7.
} bj7MzlGFy
]EM)_ :tRf
/** +:"6`um|
* @return Returns the content. { 1@4}R4
*/ 32 1={\X
publicList getContent(){ P"=UI$HN
return content; bN4&\d*u#
} 7 xp1\j0
)YnI!v2T
/** @x=BJuUuX
* @return Returns the page. o?va#/fk
*/ CS;W)F
public Page getPage(){ K_&c5(-(_
return page; A:.IBctsd
} YoF\MT]W
!HR2Rf l
/** lNaez3
* @param content Ie2w0Cs28
* The content to set. .hQ3A"
*/ CFBUQMl>
public void setContent(List content){ GIC"-l1\
this.content = content; iVq#aXN
} {wpMg
g8+4$2`ny
/** _PyW=Tj
* @param page 5"}y\
* The page to set. %%as>}.
*/ ?K4.L?D#J
publicvoid setPage(Page page){
?+
-/';
this.page = page; FI`nRFq)C
} (pE\nuA\
} 7TV>6i+7
v#:+n+y\z
w%8ooQ|C
Krp
<bK6
d(X\B{
2. 编写业务逻辑接口,并实现它(UserManager, *X=@yB*aK
L,L ~
.E
UserManagerImpl) r;cI}'
java代码: m6_~`)R8
#}/cM2m
I3 G*+6V
/*Created on 2005-7-15*/ ~jp!"f
package com.adt.service; +H[}T ]
s`Yu"s
8}4
import net.sf.hibernate.HibernateException; iJ`%yg,
qXrt0s[
import org.flyware.util.page.Page; ;L
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%s
nc3ltT,R
import com.adt.bo.Result; -uv
9(r\P
<}28=d
/** K-2o9No?j`
* @author Joa vs\'1^*D
*/ ldAov\X
publicinterface UserManager { )g9)IF
|t4Gz1"q=8
public Result listUser(Page page)throws Tn4W\?R
$z2xZqe
HibernateException; "ib K1}-
lL:KaQ 0E
} A~6%,q@^jh
Qb!!J4|!
z'?7]C2b
:LZ-da"QR
f$1Gu
java代码: CN\|_y
-Q<z1vz
t(J![wB}
/*Created on 2005-7-15*/ 0Y5LDP
package com.adt.service.impl; v%H"_T
pau*kMu^}
import java.util.List; tJUVw=
{E3xI2
import net.sf.hibernate.HibernateException; Ne &Xf
o,?!"*EP
import org.flyware.util.page.Page; =7 Jy
import org.flyware.util.page.PageUtil; pT("2:)x
V*6l6-y~Ih
import com.adt.bo.Result; a4A`cUt
import com.adt.dao.UserDAO; ]$m#1Kj
import com.adt.exception.ObjectNotFoundException; "
Sc5qG
import com.adt.service.UserManager; Y3vX)D}
1YJ_1VJ
/** GXT]K>LA
* @author Joa ad"'O]
*/ \@Ee9C13
publicclass UserManagerImpl implements UserManager { p&i.)/
J"%8:pL
private UserDAO userDAO; Ho|o,XvLv
hMNJ'i}
/** Wyy^gJl
* @param userDAO The userDAO to set. wVx,JL5Jr
*/ =LlLE<X"%x
publicvoid setUserDAO(UserDAO userDAO){ FWuw/b$
this.userDAO = userDAO; /Jh1rck
} $T"h";M)s
_REqT
/* (non-Javadoc) `+roQX.p
* @see com.adt.service.UserManager#listUser C1h#x'k
y\^@p=e
(org.flyware.util.page.Page) O {PW
*/ nAIH`L"X
public Result listUser(Page page)throws 5JS ZLC
xLA~1ZSVJw
HibernateException, ObjectNotFoundException { mbF(tSy
int totalRecords = userDAO.getUserCount(); rei
8LW
if(totalRecords == 0) dX_!0E[c
throw new ObjectNotFoundException Wt>J`
x|.v{tQa
("userNotExist"); mfZ)^X
page = PageUtil.createPage(page, totalRecords); ]kRI}Om2
List users = userDAO.getUserByPage(page); qOW#Q:T
returnnew Result(page, users); t:\l&R&
} ~V @;(_T
X6Un;UL
} p`d
XqW
2Oyy`k
@'*eC}\E
2$M,*Dnr
g.9L)L
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 DH:J
E [S?
b=^
询,接下来编写UserDAO的代码: Iha[Gu
3. UserDAO 和 UserDAOImpl: ;xfO16fNk
java代码: 3FFaEl
(@+h5@J[`I
!6M Bxg >
/*Created on 2005-7-15*/ ar Q)%W
package com.adt.dao; %Nj #0YF]
QS^~77q
import java.util.List; BU!#z(vU
J5;5-:N
import org.flyware.util.page.Page; xZX`%f-
W$r^
import net.sf.hibernate.HibernateException; @c Z\*,T
gc##V]OD
/** Hk@r5<{
* @author Joa XlVc\?
*/ >W
r$Y{
publicinterface UserDAO extends BaseDAO { eI^gV'UK
0mTEim
publicList getUserByName(String name)throws jO=*:{#x
3 -tO;GKb
HibernateException; :V-k'hm
&
69Nw/$
publicint getUserCount()throws HibernateException; 80|onP\L
<|a=hHPi:
publicList getUserByPage(Page page)throws \^9pW 2v
EJ`Q8uz
HibernateException; :/6()_>bO
E4r.ky`#~
} I FsE!oDs4
r@k"4ce-
'99@=3AB:`
GzdRG^vN
fYB*6Xb,w
java代码: .$Y?
W<
oE1M/*myS
{SJsA)9:#
/*Created on 2005-7-15*/ )B ;M
package com.adt.dao.impl; +oZH?N4yaM
b0 &
import java.util.List; +Qs!Nhsq
TiyUr [
import org.flyware.util.page.Page; m2(E>raV6
T6uMFD4 |
import net.sf.hibernate.HibernateException; !{(ls<
import net.sf.hibernate.Query; ^LVk5l)\>g
Um z05*
import com.adt.dao.UserDAO; y@3Q;~l,
ePEe?o4;
/** :m Kxa
* @author Joa Me,<\rQ
*/ !MoOKW
public class UserDAOImpl extends BaseDAOHibernateImpl
Yl~$V(
L+.H z&*@
implements UserDAO { M\9F:.t=
cvfUyp;P
/* (non-Javadoc) IE;\7r+h
* @see com.adt.dao.UserDAO#getUserByName Qs l80~n_7
|n`PESf_
(java.lang.String) &RW`W)0;
*/ j0x5@1`6G
publicList getUserByName(String name)throws ZVL
gK}s
>aG= T{
HibernateException { +AoP{x$Ia
String querySentence = "FROM user in class U;U08/y
g*y/j]
com.adt.po.User WHERE user.name=:name"; z]=8eV\
Query query = getSession().createQuery NEVp8)w
s?c JV`
(querySentence); 5/?P|T
query.setParameter("name", name); @7W?8
return query.list(); qSTW b%
} rslvsS:
jXp. qK\"
/* (non-Javadoc) c<4F4k7
* @see com.adt.dao.UserDAO#getUserCount()
$:EG%jl
*/ Uw)=WImz[
publicint getUserCount()throws HibernateException { CxDcY
int count = 0; a9l8{3
String querySentence = "SELECT count(*) FROM 8z}^jTM
AbfZ++aJ
user in class com.adt.po.User"; NYB "jKMk
Query query = getSession().createQuery . I==-|
Vb!O8xV4;+
(querySentence); c-B/~&
count = ((Integer)query.iterate().next M'2r@NR8
){P^P!s$
()).intValue(); ?pG/m%[
return count; =45W\
} kRlA4h1u_$
q]FBl}nwl%
/* (non-Javadoc) 9S>g6}[E#0
* @see com.adt.dao.UserDAO#getUserByPage +sf .PSz$
!^WHZv4
(org.flyware.util.page.Page) H0>yi[2f
*/ f~ZEdq8
publicList getUserByPage(Page page)throws hw=GR_,
89HsPB1"t
HibernateException { #jA) >z\Q^
String querySentence = "FROM user in class 1e}8LH7
0<.RA%dj
com.adt.po.User"; "0Q1qZ
Query query = getSession().createQuery O/b+CSS1
C:i|-te
(querySentence); 7-*=|gl+
query.setFirstResult(page.getBeginIndex()) V%NeZ1{ e
.setMaxResults(page.getEveryPage()); K_ke2{4Jm
return query.list(); UyiJU~r1
} aG{$Ic
u9Y3?j,oC
} ]
fwZAU
{(tHk_q
Ri)uq\E/#
9Ah[rK*}
8-Me.2K
至此,一个完整的分页程序完成。前台的只需要调用 jfp z`zE
qP1FJ89H
userManager.listUser(page)即可得到一个Page对象和结果集对象 Vn|1v4U!
I7(?;MpI
的综合体,而传入的参数page对象则可以由前台传入,如果用 nidr\oFUIn
0*F}o)n/m
webwork,甚至可以直接在配置文件中指定。 sKL:p3r
$,27pkwHeW
下面给出一个webwork调用示例: f.6~x$:)`E
java代码: rs-,0'z,7
)T|L,Lp
%J~WC$=Qv
/*Created on 2005-6-17*/ p&Ed\aQ%z;
package com.adt.action.user; _O]xey^r
:50b8
import java.util.List; }dYBces
2+Rv{%
import org.apache.commons.logging.Log; L{&U V0q!
import org.apache.commons.logging.LogFactory; A''pS
import org.flyware.util.page.Page; :/N+;- 18
/*rhtrS)
import com.adt.bo.Result; QHlU|dR)Ry
import com.adt.service.UserService; #hw>tA6
import com.opensymphony.xwork.Action; d~9!,6XM
0
n
vSvk
/** 1G^#q,%X_v
* @author Joa GJA`l8`SQ
*/ se9>.}zZN
publicclass ListUser implementsAction{ j
!H^-d}q
sa&) #Z:
privatestaticfinal Log logger = LogFactory.getLog 3tAU?sV!
bt/ =Kq#
(ListUser.class); y2|R.EU\m<
p $`92Be/
private UserService userService; DAO]uh{6
%)(Cp-b!
private Page page; 3n;K!L%zMT
K8I$]M
privateList users; 6'-As=iw
+.yT/y "
/* =E*Gb[r_7
* (non-Javadoc) Y.6SOu5$]
* u bW]-U=T
* @see com.opensymphony.xwork.Action#execute() xTz%nx
*/ vVxD!EL
publicString execute()throwsException{ s1j{x&OSq
Result result = userService.listUser(page); g(E"4M@t!
page = result.getPage(); t^tmz PWA
users = result.getContent(); gm"#:< )
return SUCCESS; }6u2*(TmD
} 8|^CK|m6*
{*m ?Kc7k
/** SPkn3D6
* @return Returns the page. ipE]}0q
*/ <wd]D@l7r
public Page getPage(){ K9Hqq7"%
return page; }^kL|qmjR
} K`-!uZW:B7
#]Y>KX2HG
/** Nf41ZT~
* @return Returns the users. /8'S1!zc
*/ 5 `/< v^
publicList getUsers(){ rf&M!d}!
return users; %3r:s`{
} z(y*hazK
Di.3113t
/** Xd
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* @param page WYcA8X/
* The page to set. 5e8AmY8;
*/ }2 8=
publicvoid setPage(Page page){ *Mc7f ?H
this.page = page; w8Sv*K
} \*t~==WB
Y"g.IK`V
/** ,F6=b/eZ
* @param users pc]J[ S?P
* The users to set. XRN+`J
*/ iUk-'
publicvoid setUsers(List users){ 0#o/ ^Ah
this.users = users; k(VB+k"3
} ,5
j"ruZ
Q,T"Zd Q
/** O`1!
* @param userService w4,Ag{t>
* The userService to set. o`S?
*/ OWq'[T4
publicvoid setUserService(UserService userService){ 1 T<+d5[C
this.userService = userService; I{'f|+1
} >4` dy
} [(kB
5 a
. 5y"38e
ZzGahtx)Y
ym,H@~
iRo.RU8>
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ;h=*!7:
E(pF:po
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 {PU!=IkTS
'wasZ b<^
么只需要: UB`ToE|Ii
java代码: q<W=#Sx
W<ZK,kv
^ >x|z.
<?xml version="1.0"?> qVqRf.-\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork u|#>32kV
4LcX<BU9
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [jdFA<Is
INs!Ame2
1.0.dtd"> e1myH6$W
%VJ85^B3
<xwork> lf<S_2i
ZIR0PQh\
<package name="user" extends="webwork- 1F8 W9b^D
f"u*D,/sS
interceptors"> <:>SGSE9
4BYE1fUzd
<!-- The default interceptor stack name EI>6Nh
%=we`&
--> Z7rJ}VP
<default-interceptor-ref o{b=9-V
EJ}!F?o
name="myDefaultWebStack"/> g>0XxjP4
-{XRA6
<action name="listUser" O`GsS{$sS
r~-.nb"P
class="com.adt.action.user.ListUser"> {#P`^g
<param x&Vm!,%:1
AmPMY:1i"
name="page.everyPage">10</param> WL,&-*JAW
<result rB~W Iu
j:T/ iH!YF
name="success">/user/user_list.jsp</result> []R? ViG
</action> o;a:Dd
6Tw#^;q-
</package> %
}|cb7l
eivtH P
</xwork> 0_P}z3(M
anw}w!@U
#PDf,^
HjqB^|z
,B(7\
/iNa'W5\
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 >h2%[j=
uJHu>M}~
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。 v[@c*wo
87)zCq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 G&xo1K]
hv 6@Jr3
_Y=2/*y^
<^~FLjsfg
.?p\n7
我写的一个用于分页的类,用了泛型了,hoho /&& 2u7*
do-ahl,
java代码: aSuM2
,:fl?x.X
07Gv* .
package com.intokr.util; w;}@'GgL
`~eX55W
import java.util.List; b `2|I {
;4M><OS!
/** a07@C
* 用于分页的类<br> tkQH\5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> =~Ynz7 /x
* )#a[-.OI
* @version 0.01 <^b7cOFQ
* @author cheng G2LK]
*/ <H1`
public class Paginator<E> { n,eJ$2!J
privateint count = 0; // 总记录数 YSJy`
privateint p = 1; // 页编号 Qu5UVjbE,
privateint num = 20; // 每页的记录数 L%v^s4@
privateList<E> results = null; // 结果 ,uw132<b
ONNpiK-
/** ,:~0F^z
* 结果总数 6)oLus
*/ W"{v2x i
publicint getCount(){ QB:i/9
return count; 4k/VBZB
} E3@QI?n^^
{mWui9 %M
publicvoid setCount(int count){ }>^Q'BW;65
this.count = count; 4L-:*b_v\
} L-pVltX
xvzr:pP
/** -yGDh+-
* 本结果所在的页码,从1开始 ,*4p?|A
* i |{Dd%4vK
* @return Returns the pageNo. )eUW5
tS
*/ Zh5RwQNE~
publicint getP(){ p~ C.IG
return p; VL[R(a6c
<
} -/_L*oYli
AC
O)Dt(Y
/** GV)<Q^9
* if(p<=0) p=1 2fU$J>Y
* !zPG?q]3
* @param p "dR|[a<#g
*/ $M_x!f'{>
publicvoid setP(int p){ mrm^e9*Z
if(p <= 0) >FhK#*Pa
p = 1; ,f}UGd[a
this.p = p; ug{R 3SS
} hjO*~
WwC 5!kZ
/** 2([2Pb3<"
* 每页记录数量 vHAg-Avc
*/ 7iHK_\t n
publicint getNum(){ 2L AYDaS
return num; V`adWXu
} h8\
T
th6+2&B6
/** Qn ^bVhG+
* if(num<1) num=1 o7B[R) 4
*/ t9&cE:n
publicvoid setNum(int num){ ZKg{0DY
if(num < 1) Xtwun
num = 1; AamVms
this.num = num; =9kN_:-
} h._nK\
?ER-25S
/** T&86A\D\z
* 获得总页数 "x@='>:$
*/ p8s:g~ W
publicint getPageNum(){ "<}&GcJbz
return(count - 1) / num + 1; [1 Ydo`
} A2}Rl%+X]6
MNH1D!}
/** tbnH,*
* 获得本页的开始编号,为 (p-1)*num+1 !*2%"H*
*/ dd?x(,"A`
publicint getStart(){ 0y&I/2
return(p - 1) * num + 1; 8/z3=O&
} SuZ&vqS
Z):n c% S
/** $3Z-)m
* @return Returns the results. 7PR#(ftz
*/ B?$ "\;&
publicList<E> getResults(){ m/N dJMoN=
return results; 3] 1-M
} OB~X/
ExHKw~y9
public void setResults(List<E> results){ ^m_yf|D$
this.results = results; nm7;ieMfr
} H:p Z-v*
fYE(n8W3
public String toString(){ /6O??6g
StringBuilder buff = new StringBuilder 1FtM>&%4
9Lh|DK,nV/
(); Le"oAA#[
buff.append("{"); syip; ;
buff.append("count:").append(count); lnE+Au'
buff.append(",p:").append(p); ]|_\xO(
buff.append(",nump:").append(num); yqSs,vz
buff.append(",results:").append Tz2-Bp]h
(M
=Y&M'f
(results); m]*Bx%-1c
buff.append("}"); vK$"# F~
return buff.toString(); g'];Estb~
} 9 2MTX
Osp
[FUjnI
} <o2r~E0r3
`.y}dh/+0W
d--y