Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 xU&rUk/L
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H\^^p!^)
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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 +SJ aE] $
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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 kxP6#8*:
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分页支持类: I9MI}0}7
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java代码: oeIS&O.K
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package com.javaeye.common.util; S.I<Hs
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import java.util.List; A-~)7-
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publicclass PaginationSupport { k4@GjO1"$
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publicfinalstaticint PAGESIZE = 30; L]VK9qB
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privateint pageSize = PAGESIZE; 7+c@pEU]
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privateList items; 3S,pd0;
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privateint totalCount; kSDV#8uZ
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privateint[] indexes = newint[0]; B4b UcYk
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privateint startIndex = 0; QhZ%<zN
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public PaginationSupport(List items, int CI,-qi
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totalCount){ BP7_o63/G
setPageSize(PAGESIZE); ka5>9E
setTotalCount(totalCount); X[|>r@Aa!
setItems(items); ugCc&~`
setStartIndex(0); ovHbs^H%
} !xlVyt5e
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public PaginationSupport(List items, int n"pADTaB
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totalCount, int startIndex){
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setPageSize(PAGESIZE); %!q(zql
setTotalCount(totalCount); Yc
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setItems(items); v|hi;l@7E
setStartIndex(startIndex); K+7xjFoDIR
} [;2v[&Po
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public PaginationSupport(List items, int xW09k6
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totalCount, int pageSize, int startIndex){ mMMu'N
setPageSize(pageSize); 464Z0C
setTotalCount(totalCount); n_!&Wr^CX
setItems(items); UKzmRa,s
setStartIndex(startIndex); &@RU}DnvM&
} # WxH
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publicList getItems(){ mdk:2ndP
return items; ^^[,aBu
} l/`Z+];
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publicvoid setItems(List items){ vb%\q sf
this.items = items; tpVtbh1)u
} ]6nF>C-C
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publicint getPageSize(){ )j$Bo{
return pageSize; -H]svOX
} ^yX
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publicvoid setPageSize(int pageSize){ (R0
this.pageSize = pageSize; H'Po
} LWW0lG!_F
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publicint getTotalCount(){ Ah"RxA
return totalCount; !ine|NM
} )S`A+M K]
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publicvoid setTotalCount(int totalCount){ d BJM?/
if(totalCount > 0){ b w cPY
this.totalCount = totalCount; /r)d4=1E
int count = totalCount / /qz(ra
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pageSize; )~Q$ tM`
if(totalCount % pageSize > 0) s^AYPmR6
count++; gKPV*
indexes = newint[count]; 4b(iGLrt0
for(int i = 0; i < count; i++){ H<qR^a
indexes = pageSize * RpreW7B_Q*
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i; ^{bP#f
} \'p)kDf
}else{ Wl*\kQ}U
this.totalCount = 0; Z8:iaP)
} `=.{i}V
} `aC#s3[
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publicint[] getIndexes(){ co;2s-X
return indexes; kt@+UK."
} h rZ\ O?j
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publicvoid setIndexes(int[] indexes){ ";GLX%C!{@
this.indexes = indexes; 9eV@v
} = 7jkW (Q
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publicint getStartIndex(){ D3jP hPy.
return startIndex; UH)A n:9
} Z(V4"x7F
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publicvoid setStartIndex(int startIndex){ [6c{t
if(totalCount <= 0) >si<VCO
this.startIndex = 0; ){6;o&CC:
elseif(startIndex >= totalCount) <|.M]]}j
this.startIndex = indexes kQj8;LU
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[indexes.length - 1]; alq>|,\x
elseif(startIndex < 0) I5-/KVWb
this.startIndex = 0; C[[z3tn
else{ q-uYfXZ{j
this.startIndex = indexes y(q1~73s
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[startIndex / pageSize]; jx-W$@
} K%Rx5 S
} ' rXkTm1{
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publicint getNextIndex(){ &^z~wJ,]
int nextIndex = getStartIndex() + G;tIhq[$Vb
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pageSize; B^KC~W
if(nextIndex >= totalCount) <yIJ$nBx
return getStartIndex(); ."MBKyg6
else ]qrO"X=
return nextIndex; )[/+j"F
} `B^?Za,xN
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publicint getPreviousIndex(){ KC
int previousIndex = getStartIndex() - ??k^Rw+0R
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pageSize; ($ae n
if(previousIndex < 0) zRu}lJ1#W$
return0; b7=]"|c$@
else !QYqRH~5
return previousIndex; fIFB"toiPE
} Q~`]0R159e
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} Ha;^U/0|
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抽象业务类 W~gFY#w
java代码: 8pPAEf
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/** d]+g3oy
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* Created on 2005-7-12 4Jht{#IIG
*/ B:Msn)C~
package com.javaeye.common.business; ]x~H"<V
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import java.io.Serializable; rU(N@i%
import java.util.List; pnVtjWrbG
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import org.hibernate.Criteria; #OG_OI
import org.hibernate.HibernateException; M)Y`u
import org.hibernate.Session; Ib]{rmaP
import org.hibernate.criterion.DetachedCriteria; rjfQ\W;}U
import org.hibernate.criterion.Projections; x@Q}sW92
import ]W]Vkkg]
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org.springframework.orm.hibernate3.HibernateCallback; ?e yo2:-$
import ij%\ld9kd
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org.springframework.orm.hibernate3.support.HibernateDaoS 0hCJovSG%
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upport; CkIICx
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import com.javaeye.common.util.PaginationSupport; LkNC8V
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public abstract class AbstractManager extends % &{>oEQ
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HibernateDaoSupport { YQ2ie>C8
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privateboolean cacheQueries = false; =XyK/$
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privateString queryCacheRegion; )7:2v1Xr]
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publicvoid setCacheQueries(boolean "o%N`Xlx
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cacheQueries){ oO!@s`
this.cacheQueries = cacheQueries;
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} tOS%.0W5J
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publicvoid setQueryCacheRegion(String i3N _wv{
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queryCacheRegion){ fq_ 6xs
this.queryCacheRegion = }h EBX:-
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queryCacheRegion; wvsTP32]
} wbVM'E/&
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publicvoid save(finalObject entity){ ,.G6c=pZ
getHibernateTemplate().save(entity); eRv3qK{`
} 1z0&+ C3z
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publicvoid persist(finalObject entity){ d{I|4h
getHibernateTemplate().save(entity); ]g!k'@
} QV7K~qi
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publicvoid update(finalObject entity){ 5c`DkWne%
getHibernateTemplate().update(entity); % ;09J
} 8kX3.X`
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publicvoid delete(finalObject entity){ hPP+lqY[
getHibernateTemplate().delete(entity); /w`{]Ntgu
} C
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publicObject load(finalClass entity, uXyNj2(d.
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finalSerializable id){ wlmi&kq
return getHibernateTemplate().load u3w `(3{<
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(entity, id); Ds$FO}KD{
} ,H[-.}OO
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publicObject get(finalClass entity, VNx}ADXu ]
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finalSerializable id){ a:7"F{D91
return getHibernateTemplate().get mRxL%!
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(entity, id); qXCl6Yo8
} :Dw;RcZQ
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publicList findAll(finalClass entity){ S\MD]>4
return getHibernateTemplate().find("from O"nY4
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" + entity.getName()); \bZbz/+D
} M
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publicList findByNamedQuery(finalString VEd\*
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namedQuery){ *.~hn5Y|?
return getHibernateTemplate )j]S;Mr
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().findByNamedQuery(namedQuery); !s9<%bp3
} `9kjYSd#E
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publicList findByNamedQuery(finalString query, >/ECLP
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finalObject parameter){ AW!|xA6'`:
return getHibernateTemplate VgN`'
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().findByNamedQuery(query, parameter); ig7)VKr
} g*AnrQ}P
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publicList findByNamedQuery(finalString query, 5MO:hE5sm
BAx)R6kS;
finalObject[] parameters){ JOx75}
return getHibernateTemplate ^Qs-@]E-
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().findByNamedQuery(query, parameters); \b1I<4(
} ;yx+BaG~?
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publicList find(finalString query){ \"<&8
return getHibernateTemplate().find P (_:8|E
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(query); (IAl$IP63s
} k'xnl"q
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publicList find(finalString query, finalObject 8L|rj4z<#
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parameter){ 7"Zr:|$U
return getHibernateTemplate().find e*jn7aya
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(query, parameter); 7Q/v#_e(
} LGgEq-
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public PaginationSupport findPageByCriteria BB1'B-O
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(final DetachedCriteria detachedCriteria){ `Z{;
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return findPageByCriteria EN+WEMro
L` V6\Ix(I
(detachedCriteria, PaginationSupport.PAGESIZE, 0); o`DBzC
} i/,G=yA
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public PaginationSupport findPageByCriteria EJNj.c-#
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(final DetachedCriteria detachedCriteria, finalint Z>7Oez>
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startIndex){ GLv}|>W
return findPageByCriteria tV[?WA[xt
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(detachedCriteria, PaginationSupport.PAGESIZE, qF%wl
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startIndex); +`yDW N?7
} "k"q)5c
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public PaginationSupport findPageByCriteria Ni"fV]'
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(final DetachedCriteria detachedCriteria, finalint \Nb6E&+
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pageSize, ) Z0
finalint startIndex){ XqyfeY5t
return(PaginationSupport) VCX})sp
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate YEXJh!X
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(Session session)throws HibernateException { c_kxjzA#
Criteria criteria = H)
m!)=\'
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detachedCriteria.getExecutableCriteria(session); kVe^g]F
int totalCount = s><RL]+{G+
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((Integer) criteria.setProjection(Projections.rowCount b!PN6<SI
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()).uniqueResult()).intValue(); )d>"K`3
criteria.setProjection >Djv8 0
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(null); $*G]6s
List items = 4<ER
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criteria.setFirstResult(startIndex).setMaxResults 8:huWjh]M
:c!7rh7O
(pageSize).list(); kD >|e<}\
PaginationSupport ps = oMkB!s
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new PaginationSupport(items, totalCount, pageSize, [
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startIndex); GNZQj8
return ps; shYcfLJ
} N{q5E,}
}, true); Q'7o_[o/
} .J&NM(qeZ
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public List findAllByCriteria(final P`-(08t
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DetachedCriteria detachedCriteria){ fx99@%Ii
return(List) getHibernateTemplate S]K^wj[
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().execute(new HibernateCallback(){ dn:g_!]p
publicObject doInHibernate (|(Y;%>-v
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(Session session)throws HibernateException { _@F4s
Criteria criteria = / (W{`
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detachedCriteria.getExecutableCriteria(session); v?K
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return criteria.list(); Nr:%oD_G*
} i._d^lR\t
}, true); K{x<zv&,
} =y0!-y
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public int getCountByCriteria(final y!blp>V6
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DetachedCriteria detachedCriteria){ U87VaUr
Integer count = (Integer) *h@nAB\3
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getHibernateTemplate().execute(new HibernateCallback(){ 7M3q|7?
publicObject doInHibernate }1:jM_H)k
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(Session session)throws HibernateException { o!sxfJKl
Criteria criteria = rYJt;/RtR}
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detachedCriteria.getExecutableCriteria(session); O4]Ss}ol
return Q\m"n^XN
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criteria.setProjection(Projections.rowCount E36<Wog
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()).uniqueResult(); vkc(-n
} HR['y9U
}, true); " &p\pR~
return count.intValue(); i*.Z~$
} L L9I:^
} 8%arA"#S
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用户在web层构造查询条件detachedCriteria,和可选的 $v-lG(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4y>G6TD^
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 cvn,&G-`
ps.getIndexes()得到分页索引的数组 |n01T_Z)P
ps.getTotalCount()得到总结果数 je_77G(F
ps.getStartIndex()当前分页索引 b]hRmW
ps.getNextIndex()下一页索引 =1VY/sv
ps.getPreviousIndex()上一页索引 1?E\2t&K
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~4XJ" d3L
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @^k$`W;
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一下代码重构了。 <0JW[m
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我把原本我的做法也提供出来供大家讨论吧: zh*NRN
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首先,为了实现分页查询,我封装了一个Page类: 6l:CDPhR
java代码: \DeZY97p%
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/*Created on 2005-4-14*/ gbXzD`WQ
package org.flyware.util.page; BCsW03sQ
#V4_. t#
/** &&_W,id`
* @author Joa =qIJXV
* A' dt
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*/ WdunI~&.
publicclass Page { rh$%*l
dYfVox;
/** imply if the page has previous page */ M~ynJ@q
privateboolean hasPrePage; z4UeUVfZ}
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/** imply if the page has next page */ sx`C<c~u
privateboolean hasNextPage; `4\ H'p
xCoQ>.4p
/** the number of every page */ Ms{v;fT
privateint everyPage; -_b}b)2iYN
42Kzdo|}
/** the total page number */ R^%7|
privateint totalPage; K'1rS[^>R
}KS[(Q
/** the number of current page */ 0DS<(
privateint currentPage; UL"JwqD
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/** the begin index of the records by the current I#uJdV|x
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query */ 7Py8!
privateint beginIndex; "z@qG]#5
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/** The default constructor */ N9,n/t
public Page(){ &*/X*!_HK
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} pm3?
;}^Pfm8
/** construct the page by everyPage J~n{gT<L
* @param everyPage 'T+3tGCy+
* */ P(A%z2Ql
public Page(int everyPage){ NrS1y"#d9
this.everyPage = everyPage; (MJu3t
@
} =_.Zv
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/** The whole constructor */ l ^\5Jr03
public Page(boolean hasPrePage, boolean hasNextPage, E*rDwTd
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int everyPage, int totalPage, ^[^uDE
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int currentPage, int beginIndex){ =0x[Sa$&,
this.hasPrePage = hasPrePage; X}
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this.hasNextPage = hasNextPage; >MiA|N=
this.everyPage = everyPage; *K-,<hJ#L
this.totalPage = totalPage; dIIsO{Zqv
this.currentPage = currentPage; G}}oeS
this.beginIndex = beginIndex; >Pbd#*
} }{]{`\
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/** U/0NN>V
* @return "QGP]F
* Returns the beginIndex. fv<($[0
*/ f8'&(-
publicint getBeginIndex(){ 9I^_n+E
return beginIndex; ]yCmGt+b
} }b6ja y
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/** $~ zqt%}
* @param beginIndex C.pNDpx-
* The beginIndex to set. d3^LalAp
*/ >{npg2
publicvoid setBeginIndex(int beginIndex){ WpSdukXY{
this.beginIndex = beginIndex; ZaXK=%z
} =2->1<!x6<
>/$Q:92T
/** n'%*vdHKm
* @return o(|`atvK
* Returns the currentPage. 3vVhE,1N
*/ _%Mu{Ni&
publicint getCurrentPage(){ %)\Cwl
return currentPage; DRf~l9f
} p5G O@^i
4?72TBl]
/** fN8A'p[
* @param currentPage N#]f?6*R
* The currentPage to set. kwZC3p\\
*/ fs~n{z,ja%
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; NoZz3*j=
} Oh<Z0M)
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/** _qJ[~'m<^C
* @return 2ORWdR.b
* Returns the everyPage. oBKZ$&_h
*/ >nvreis
publicint getEveryPage(){ $0iz;!w
return everyPage; !4I?59
} LNk
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/** -[Zau$;J<
* @param everyPage cnCUvD]'
* The everyPage to set. -"!V&M
*/ fgTvwOSk
publicvoid setEveryPage(int everyPage){ |w /txn8G|
this.everyPage = everyPage; *~2jP;$
} jwAO{.}T1r
q`9~F4\
/** -+Quw2465^
* @return `C_#EU-
* Returns the hasNextPage. dpE\eXoa,
*/ {&w%3
publicboolean getHasNextPage(){ }wj*^>*
return hasNextPage; )k29mqa`
} #; }IHAR
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/** ^D oJ='&
* @param hasNextPage BFj@Z'7P
* The hasNextPage to set. Yg2z=&p-{"
*/ .B#Lt,m
publicvoid setHasNextPage(boolean hasNextPage){ C'7W50b
this.hasNextPage = hasNextPage; :qgdn,Me
} 6TPcG d Z
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/** SuGlNp>#qm
* @return A(;J
* Returns the hasPrePage. d'Gv \i&e
*/ z?1GJ8
publicboolean getHasPrePage(){ |byB7f
return hasPrePage; $_)YrqSo~
} n'4D ;4
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/** X] Tb4
* @param hasPrePage _mXq]r0
* The hasPrePage to set. =CRaMjN
*/ B;W=61d
publicvoid setHasPrePage(boolean hasPrePage){ e/@udau
this.hasPrePage = hasPrePage; Yn1 U@!
} !j YV,:'
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b
/** \UtUP#Y{t
* @return Returns the totalPage. 0Xk;X1Xl
* w[4SuD
*/ Dtd
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publicint getTotalPage(){ pc-'+7Dh>
return totalPage; <| Z0|sel
} ,EwJg69
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/** Of([z!'Gc
* @param totalPage Ie4*#N_
* The totalPage to set. uz'beE
*/ |W:kzTT-T
publicvoid setTotalPage(int totalPage){ ua7I K~8l
this.totalPage = totalPage; ~}4H=[Zu
} nwcT8b87J
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} s8eiq`6\H}
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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 Kau*e8
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个PageUtil,负责对Page对象进行构造: WxO*{`T!
java代码:
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/*Created on 2005-4-14*/ |U7{!yy%MF
package org.flyware.util.page; 3P-#NL
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import org.apache.commons.logging.Log; 9iS3.LCfX
import org.apache.commons.logging.LogFactory; pLyX9C
$8_*LR$
/** hc0VS3 k)
* @author Joa P?]q*KViM
* :I<%.|8
*/ 8eOQRC33
publicclass PageUtil { *bv
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privatestaticfinal Log logger = LogFactory.getLog m^]/
/j
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(PageUtil.class); <;U"D.'
cpE&Fba}"
/** wQ[2yq
* Use the origin page to create a new page !lu$WJ{M
* @param page Z|wZyt$$
* @param totalRecords *+@/:$|U
* @return 7*[>e7:A
*/ 6e~+@S
publicstatic Page createPage(Page page, int j&8 ~X2?*
Oa@X! \
totalRecords){ dWm[#,Q?
return createPage(page.getEveryPage(), !4oYQB
#axRg=d?K
page.getCurrentPage(), totalRecords); |'KNR]:
N
} h)A+5^:^
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/** UI;!_C_
* the basic page utils not including exception <w2Nh eM 3
|<BTK_R
handler U*a!Gn7l
* @param everyPage ={feN L
* @param currentPage k5}i^^.
* @param totalRecords dc lJ
* @return page Bwll
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*/ uVisU%p
publicstatic Page createPage(int everyPage, int %FyB\IQ
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currentPage, int totalRecords){ mX |AptND
everyPage = getEveryPage(everyPage); ]7xAL7x
currentPage = getCurrentPage(currentPage); m41n5T`
int beginIndex = getBeginIndex(everyPage, ""WZpaw
}^LcKV
currentPage); &+sO"j4<?r
int totalPage = getTotalPage(everyPage, @)}Vk
2'pxA:
totalRecords); 0s<o5`v
boolean hasNextPage = hasNextPage(currentPage, RKBjrSZg8
7Uj[0Awn
totalPage); j j$'DZk
boolean hasPrePage = hasPrePage(currentPage); K5w22L^=+
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returnnew Page(hasPrePage, hasNextPage, v3]q2*`G#
everyPage, totalPage, E176O[(V=
currentPage, d3n TJ X
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beginIndex); Tmw
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} .s2d
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privatestaticint getEveryPage(int everyPage){ u\t ;
return everyPage == 0 ? 10 : everyPage; C($`'~b
} wbr"z7}
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privatestaticint getCurrentPage(int currentPage){ PfuYT_p4s
return currentPage == 0 ? 1 : currentPage; 0tsll1
} W}.4$f>
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privatestaticint getBeginIndex(int everyPage, int CZ&TUE|:DA
h+$_:](PC
currentPage){ %F}`;>C3
return(currentPage - 1) * everyPage; ,:L}S03k
} N!Y'W)i16
/pyKTZ|
privatestaticint getTotalPage(int everyPage, int FAQ:0L$G
?T4%"0
totalRecords){ [Cr_2
int totalPage = 0; YDQV,`S7
9r8{9h:
if(totalRecords % everyPage == 0) j,G/[V
totalPage = totalRecords / everyPage; YJ75dXc&&
else ueWG/`ig
totalPage = totalRecords / everyPage + 1 ; @*2FG\c<
=6+BBD
return totalPage; G:@gO2(D
} sV77WF
XhIgzaGVu
privatestaticboolean hasPrePage(int currentPage){ ^ePSI|EW
return currentPage == 1 ? false : true; WVo%'DtF`
} ZE=~ re
ipbVQ7
privatestaticboolean hasNextPage(int currentPage, [C d2L&9
U9N}6a=
int totalPage){ %NAz(B
return currentPage == totalPage || totalPage == @Sv
?Ar
:'rXu6c-
0 ? false : true; o oS4F1ta
} ' !_44
U}qW9X;o
iSsy_ |
} 3cfkJ|fuwe
O%+:fJz6wI
m&$H?yXW>
Z-vzq;
,,G0}N@7s
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。 U2Ur N?T
)FHaJ*&d
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 _6(zG.Fg
{+r?g J
做法如下: \|T0@V
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D(r|sw
,-{j.
的信息,和一个结果集List: u_Q3v9
java代码: >2v_fw
>c1mwZS;
L4[bm[x
/*Created on 2005-6-13*/ =)bZSb"<"
package com.adt.bo; z_Qw's
|H@M-
import java.util.List; ~XZ1,2jA/
B\("08x
import org.flyware.util.page.Page; dj]sr!q+
Nf;vUYP
/** TvQAy/Y0
* @author Joa <"\K|2Sg
*/ APLu?wy7s5
publicclass Result { +ATN2
o
.:lzT"QXI
private Page page; D<rjxP
]&9f:5',
private List content; Z
v~
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q,*IR*B:a
/** v =u|D$
* The default constructor C'=C^X%
*/ ;pU LJ}rDb
public Result(){ O}KT>84M
super(); Xz5=fj&
} VyI%^S
]sS
.KB*u*h
/**
:zZtZT!
* The constructor using fields e~-Dk .i
* TIvLY5 HG
* @param page 6}|vfw
* @param content jV7q)\uu^
*/ r[?rwc^
public Result(Page page, List content){ %`}Qkb/Lyh
this.page = page; wIY#TBu
this.content = content; !W3Le$aL
} -bj1y2)n
D'2O#Rj4q
/** Vl'=92t
* @return Returns the content. tRXM8't
*/ >PYe"
publicList getContent(){ v:vA=R2
return content; :}GxJT4
} f9&D1Gh+w
^Krkf4fO
/** pa\]@;P1
* @return Returns the page. prm
*/ ^L'K?o
public Page getPage(){ -jyD!(
return page; Nh+$'6yT%
} b;}MA7=
t7~mW$}O
/** nY*ODL
* @param content m?m,w$K
* The content to set. qQom=x
*/ w?5b: W,
public void setContent(List content){ /vQ^>2X%
this.content = content; BHK_=2WYz
} vAVoFL
GN>T }
/** jAJkCCG
* @param page WK=!<FsC$
* The page to set. 1/{:}9Z@
*/ YJ"gm]Pm
publicvoid setPage(Page page){ d)0%|yX6
this.page = page; \{&55>
} 9u)h$VC
} Og&2,`Jb
OIoAqt
|MRxm"]A
JZ<O-G+
@vv`86bm
2. 编写业务逻辑接口,并实现它(UserManager, UtWoSFZ'o!
-meKaQv
UserManagerImpl) 2?"9NQvz
java代码: G?"1
z;
h?R-t*G?
6iTDk
/*Created on 2005-7-15*/ Fj5^_2MU:
package com.adt.service; eR}d"F4W
RM`8P5i]sF
import net.sf.hibernate.HibernateException; 62zlO{ >rJ
kO5KZ;+N-
import org.flyware.util.page.Page; wJgM.V"yb
%|u"0/
import com.adt.bo.Result; r!zNcN(%cs
.58AXg
/** #
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* @author Joa &3^40s/+
*/ a{8GT2h`4
publicinterface UserManager {
wj?fr?
#F9$"L1Hg
public Result listUser(Page page)throws Uvuvr_IP
S\f^y8*<
HibernateException; 7<KRB\)b&
D,)~j6OG8
} BHU[Rz7x
wY=ky629
s+CWyW@
E+01"G<Q
lz>5bR'
java代码: `\qU.m0(j
ypsCyDQK`
2T|L##C
/*Created on 2005-7-15*/ Fdzd!r1 v
package com.adt.service.impl; l >O]Cpt
"w A8J%:
import java.util.List; IGp-`%9
:2?'mKa7
import net.sf.hibernate.HibernateException; %TR->F
8"4`W~ 3
import org.flyware.util.page.Page; >!oN+8[~
import org.flyware.util.page.PageUtil; > W0hrt?b
;j(xrPNb
import com.adt.bo.Result; cis~]x%
import com.adt.dao.UserDAO; 0 @,@
import com.adt.exception.ObjectNotFoundException; d- ]%
import com.adt.service.UserManager; x:@e ID
1'g?B`
/** .N5"IY6>
* @author Joa -Rf|p(SJ,E
*/ adxJA}K}
publicclass UserManagerImpl implements UserManager { bEy%S"\<
B8P%4@T
private UserDAO userDAO; JD'/m
hN0
!k[zUti
/** M35}5+
* @param userDAO The userDAO to set. >DV0!'jW
*/ aTPpE9Pa&
publicvoid setUserDAO(UserDAO userDAO){ --]\z* x
this.userDAO = userDAO; ~#-`Qh
} "zv+|_ZAfd
$]hf2Yr(
/* (non-Javadoc) ))MP]j9
T
* @see com.adt.service.UserManager#listUser BY 1~\M
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[^
(org.flyware.util.page.Page) rKjQEO$yi
*/ ;DGWUK.U[H
public Result listUser(Page page)throws !Q?4sAB
hR?rZUl2M
HibernateException, ObjectNotFoundException { <fyv^e
int totalRecords = userDAO.getUserCount(); 7'<4'BGzl]
if(totalRecords == 0) [s2%t"H-y
throw new ObjectNotFoundException X!"y>J
:q= XE$%H
("userNotExist"); ,= PDL
page = PageUtil.createPage(page, totalRecords); X~j
A*kmAj
List users = userDAO.getUserByPage(page); 6Qo6T][
returnnew Result(page, users); iffU}ce
} "=RB
#
p3Gj=G
} L,:U _\HQ
*yJb4uALB
g VuN a)
=CJs&Qa2
k20H|@g2
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8G@FX $$Q
[6D>2b}:{[
询,接下来编写UserDAO的代码: t ?{B*
3. UserDAO 和 UserDAOImpl: x^;nfqn|
java代码: JD>!3>S)?
|W::\yu6
2L\h+)
/*Created on 2005-7-15*/ {vU '>pp
package com.adt.dao; ?W|POk}
1ri#hm0x\
import java.util.List; &iSQ2a!l8b
Mu:H'$"'H
import org.flyware.util.page.Page; C=Zuy^
Nd0Wt4=
import net.sf.hibernate.HibernateException; weDv[b5i
y"]> Rr
/** 6jnRC*!?
* @author Joa -~xd-9v?
*/ R0+m7mx#E
publicinterface UserDAO extends BaseDAO { !7w-?1?D
H11Wb(6Wu
publicList getUserByName(String name)throws < ^&'r5H
jG/kT5S
HibernateException; '|+_~ZO*d
EXzY4D ^
publicint getUserCount()throws HibernateException; j^k{~]+_^]
LQS*/s0
publicList getUserByPage(Page page)throws NN$`n*;l
&wjOb
HibernateException; y3xP~]n
xq]&XlA:ug
} ZBYmAD
712i|
O-|3k$'\z
Tu"yoF
m760K*:i\
java代码: T&h|sa(
'R$~U?i8
0q3:"X
/*Created on 2005-7-15*/ <9Chkb|B
package com.adt.dao.impl; Ne4A
^.4<#Qs
import java.util.List; NfSe(rd
NT nn!k
import org.flyware.util.page.Page; ZqhINM*Rm
Xu
T|vh
import net.sf.hibernate.HibernateException; ="4jk=on
import net.sf.hibernate.Query; H#ihU3q
;P{ *'@
import com.adt.dao.UserDAO; 4bKZ@r%
*zx;81X=
/** v14[G@V~\
* @author Joa D`gY6wX
*/ :4A^~+J
public class UserDAOImpl extends BaseDAOHibernateImpl qR1ez-#K
q}8R>`Z{
implements UserDAO { ~!uK;hI
`j2z=5
/* (non-Javadoc) 6m{3GKaW~
* @see com.adt.dao.UserDAO#getUserByName 63~i6
\ pq]q
(java.lang.String) i.#s'm.9
*/ IQ|~d08}
publicList getUserByName(String name)throws t]m#k%)
\0:l9;^4
HibernateException { F
|GWYw'%
String querySentence = "FROM user in class 'J\%JAR@
@B[V'|
com.adt.po.User WHERE user.name=:name"; 59)PJ0E
Query query = getSession().createQuery g,1\Gj%y
_7;#0B
(querySentence); ru U|
query.setParameter("name", name);
#8(@a
Y
return query.list(); 1]qhQd-u
} C{,nDa?|
d9^h
YS{
/* (non-Javadoc) jjwY{jV
* @see com.adt.dao.UserDAO#getUserCount() +Y\#'KrA
*/ l>:?U
publicint getUserCount()throws HibernateException { "kL5HD]TC
int count = 0; +Gjy%JFp
String querySentence = "SELECT count(*) FROM eC3ZK"oJ
}b{N[
user in class com.adt.po.User"; 1\3n
Query query = getSession().createQuery 7+z%O3k'I
+F@9AO>LF
(querySentence); TcqqAc
count = ((Integer)query.iterate().next ?iq:Gf
%@IR7v~
()).intValue(); c~Ha68
return count; X-%*`XG'
} PeG8_X}u9
>97V2W
/* (non-Javadoc) 08twcY;&k
* @see com.adt.dao.UserDAO#getUserByPage )D@
NX/}
Y/4B*>kl
(org.flyware.util.page.Page) :|Z*aI]9
*/ Nc7YMxk'H
publicList getUserByPage(Page page)throws .IgCC_C9
Hu;#uAnxQ
HibernateException { a([cuh.
String querySentence = "FROM user in class ruA!+@or
S4\T (
com.adt.po.User"; hxv/285B
Query query = getSession().createQuery u=4tW:W,
9SU;c l
(querySentence); '91Ak,cWB
query.setFirstResult(page.getBeginIndex()) !]"T`^5,Y
.setMaxResults(page.getEveryPage()); cLXMq"?C
return query.list(); | 0&~fY
} %II |;<
\ET7
} BO1Mz=q
/6f$%:q
{!<zk+h$
3n,F5?!m
6.k2,C4dT<
至此,一个完整的分页程序完成。前台的只需要调用 f-3lJ?6
}?H |9OS
userManager.listUser(page)即可得到一个Page对象和结果集对象 d-c+KV
MN#\P1
的综合体,而传入的参数page对象则可以由前台传入,如果用 fghJj@ES
n0cqM}P@;!
webwork,甚至可以直接在配置文件中指定。 O6m}#?Ai/@
b>o38(
下面给出一个webwork调用示例: jirxzj
java代码: `M|fwlAJQ
m. XLpD
Xp%JPI {
/*Created on 2005-6-17*/ RCsd
package com.adt.action.user; +H+OYQ>^
9 /0<Z_b2
import java.util.List; r% qgLP{v
[]'BrG)!
import org.apache.commons.logging.Log; Xo'_|-N+
import org.apache.commons.logging.LogFactory; 0(64}T)
import org.flyware.util.page.Page; QV" |
p6sXftk
import com.adt.bo.Result; 6)Kg!.n%f
import com.adt.service.UserService; _57i[U r
import com.opensymphony.xwork.Action; }2G'3msx
x|1OGbBK
/** g#:?Ay-m
* @author Joa ':J[KWuV
*/ V+DN<F-
publicclass ListUser implementsAction{ %\CsP!
P0|V1,)
privatestaticfinal Log logger = LogFactory.getLog c!j$-Ovm
hX<0{pXM4
(ListUser.class); zsWYV n]
f BukrPsV
private UserService userService; GsxrqIaD
q.~_vS%
private Page page; Kc0KCBd8];
*Z<`TB)<X
privateList users; \y{C>!WX4
@/7tN3O
/* eR =P
* (non-Javadoc) Hh,q)(Wo
* ]^E<e!z={$
* @see com.opensymphony.xwork.Action#execute() g&X$)V4C
*/ *ewE{$UpK
publicString execute()throwsException{ yX/ 9jk
Result result = userService.listUser(page); m{;2!
page = result.getPage(); }5u$/c@f1
users = result.getContent(); :<!a.%=
return SUCCESS; ZI}7#K<9X
} e'p'{]r<w
l7n c8K
/** 6gNsh
* @return Returns the page. zcy!YB
*/ >]s|'HTxF
public Page getPage(){ QT&2&#Z
return page; +q6/'ErN]m
} A+_361KH
GMr jZ
/** ol[
* @return Returns the users. 3* 1cCM42
*/ j!F5gP-l
publicList getUsers(){ [}|x@
v9
return users; Ho2#'lSKM
} &Y4S[-
%`?IY <
/** ~ep-XO
* @param page 59 R;n.Q
* The page to set. !#Ub*qY1Z
*/ i]Njn k
publicvoid setPage(Page page){ scT,yNV
this.page = page; $qV, z
} V9mqJRFJ:
\C#XKk$OE
/** \QGh@AQp"
* @param users Op0n.\>
* The users to set. p(=}Qqdr8
*/ Cjc>0)f&.
publicvoid setUsers(List users){ +`}QIp0
this.users = users; ibAZ=RD
} xf% _HMKc
MAb*4e#
/** x-1RmL_%
* @param userService qr~P$
* The userService to set. TF R8
*/ G)t_;iNL|
publicvoid setUserService(UserService userService){ o<cg9
this.userService = userService; U[,."w]T
} iHBetkAu
} H65><38X/
>pdWR1ox
`\ _>P@qz
e ?sMOBPlv
nvY%{Zf$}
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, \MI2^JN
j*Uz.q?
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 69N/_V
{%Cb0Zh
么只需要: Vq-W|<7C=
java代码: <hkSbJF
]ie38tX$
4}.PQ{
<?xml version="1.0"?> /Z^"[Ke
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [J{\Ke0<e1
}:+SA
1.0//EN" "http://www.opensymphony.com/xwork/xwork- QP>tu1B|
*hWpJEV
1.0.dtd"> \no6]xN;
QiKci%=SX
<xwork> J'}G~rB<<
~?#>QN\\c
<package name="user" extends="webwork- F \0>/
C-)mP- |8
interceptors"> 2~`vV'K
!$n@-
<!-- The default interceptor stack name /~~A2.=.
fVJlA
--> 4|U$ON?x
<default-interceptor-ref ![3 /!
HKp|I%b]J
name="myDefaultWebStack"/> UlP2VKM1&
S3oyx#R('O
<action name="listUser" aQ.QkMZ
]w,:T/Z}
class="com.adt.action.user.ListUser"> |#(KP
<param A:b(@'h
w :nYsuF
name="page.everyPage">10</param> 5}C.^ J`
<result qTZ\;[CrP"
amTeTo]Tg
name="success">/user/user_list.jsp</result> ~F"<N q
</action> a_Sp}s<J
FP=up#zl
</package> ,ArHS
r{cmw`WA/P
</xwork> DplS\}='s
[x%[N)U3
I4XnJ[N%
baQORU=X
/Fk]>|*
O:E0htdWr
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 ZWmS6?L.
jlxY|;gZ-0
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。 YY zUg
b1TIVK3m
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Iip%er%b
dl]pdg<
Y5{KtW
I=[Ir8};
9| g]M:{
我写的一个用于分页的类,用了泛型了,hoho 'GI|
t
m>{a<N
java代码: -=cxUDB
TUBpRABH
{=%,NwPs
package com.intokr.util; a`e'HQ
Wu~cy}\
import java.util.List; K<rv|bJ
;A6%YY
/** ,xw1B-dx
* 用于分页的类<br> Tbp;xv_qo
* 可以用于传递查询的结果也可以用于传送查询的参数<br> v!`:{)2C
* WKAG)4
* @version 0.01 T>hrKn.!D:
* @author cheng aPdEEqc\l
*/ {j6$'v)0
public class Paginator<E> { 3Ofh#|qc&
privateint count = 0; // 总记录数 bey:Qj??
privateint p = 1; // 页编号 %*zV&H
privateint num = 20; // 每页的记录数 $d-$dM?R5
privateList<E> results = null; // 结果 ;kI)j
?
2YDD`:R
/** "XQ3mi`y
* 结果总数 (#?O3z1@"
*/ S zNZY&8
f
publicint getCount(){ ]]o?!NX
return count; E~@&&dU8
} [uwn\-
*sQ.y
{
publicvoid setCount(int count){ GrUpATIx
this.count = count; -5oYGLS$y3
} c,^W/:CQAB
fig~z=m
/** (mr*Thy`@
* 本结果所在的页码,从1开始 l 88n*O
* p()q)P
* @return Returns the pageNo. H_ a##z
*/ M"Af_Pbx
publicint getP(){ u6 QW*8b4
return p; TMGYNb%<bX
} ihJ!]#Fbm
ch2m Ei(
/** +DG-MM%\
* if(p<=0) p=1 `_f&T}]
* 8BrC@L2E0
* @param p GEvx<:
*/ 1s~rWnhVv
publicvoid setP(int p){ u/<ZGW(&s(
if(p <= 0) |}2/:f#Iz*
p = 1; 2D(sA
this.p = p; >/Gw)K}#E
} 7+88o:G9
{Q>4zepN!
/** >k
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* 每页记录数量 sSf;j,7V
*/ 9OFH6-;6`\
publicint getNum(){ &.(iS
return num; LF`]=.Q
} JMk2OK{0
EKO~\d
/** @3y
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* if(num<1) num=1 q:nUn?zB
*/ 3ZC@q
#R
A
publicvoid setNum(int num){ ,Ne9x\F
if(num < 1) (t){o>l
num = 1; ySI}Nm>&=
this.num = num; A;5_/ 2
} Hs$HeAp;
+PnuWK$
/** 7Vk9{x$z
* 获得总页数 UD8e,/
*/ 5t-d+vB
publicint getPageNum(){ |)xWQ KzA
return(count - 1) / num + 1; E2 FnC}#W
} $vK,Gugcx
_ X
/** .Tm.M7
* 获得本页的开始编号,为 (p-1)*num+1 l-cBN^^
*/ pHx$
publicint getStart(){ 3-E-\5I
return(p - 1) * num + 1; ~+d{:WY
} j\wZjc-j
p0y|pD
/** $tF\7.e@
* @return Returns the results. ~3-"1E>Rgy
*/ t^Lb}A#$4
publicList<E> getResults(){ C:t?HLY)fG
return results; *|j4>W\J
} w#hg_RK(Jr
k]C k%[d
public void setResults(List<E> results){ KgbBa2@+
this.results = results; :Tv>)N
} daP_Kz/2K
7x77s
public String toString(){ `\|@w@f|;
StringBuilder buff = new StringBuilder oOc-1C
y
dl3;A_ 2
(); +*xc4
buff.append("{"); r`"T{o\e
buff.append("count:").append(count); Tt9cX}&&
buff.append(",p:").append(p); k q]E@tE*3
buff.append(",nump:").append(num); {]U
\HE1w
buff.append(",results:").append yY!)2{F+
WO{7/h</
(results); IA&V?{OE@I
buff.append("}"); b%*`}B
return buff.toString(); wx`.
} ?-%(K^y4r
3UmkFK<
} "wcw`TsK
Qd\='*:!
cl1ygpf(