Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,mvFeo;@f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Rf8ZH
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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 h$$JXf
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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 x1`(Z|RJ
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分页支持类: *0@Z+'M?
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java代码: f. >[ J
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package com.javaeye.common.util; 0%,W5w
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import java.util.List; ib
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publicclass PaginationSupport { W{!5}Sh
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publicfinalstaticint PAGESIZE = 30; !Sy9v
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privateint pageSize = PAGESIZE; RrrlfF ms
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privateList items; 7Dl^5q.|
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privateint totalCount; I]5){Q"S
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privateint[] indexes = newint[0]; <_pLmYI
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privateint startIndex = 0; zA$ Y@f
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public PaginationSupport(List items, int :.l\lj0Yf
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totalCount){ G.iQ\'1_h
setPageSize(PAGESIZE); MFO%F) 5
setTotalCount(totalCount); 5>CeFy
setItems(items); ,K6ODtw.
setStartIndex(0); k5bv57@
} g(s}R ?
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public PaginationSupport(List items, int s2QgR37s>
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totalCount, int startIndex){ !=;Evf
setPageSize(PAGESIZE); ?wmu0rR
setTotalCount(totalCount); }3XjP55
setItems(items); :4X,5X7tW=
setStartIndex(startIndex); QjJlVlp
} veh=^K%G |
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public PaginationSupport(List items, int uQW[2f
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totalCount, int pageSize, int startIndex){ <?8cVLW}O
setPageSize(pageSize); C'l\4ij)7
setTotalCount(totalCount); j+/EG^*/
setItems(items); -~\7ZRP8
setStartIndex(startIndex); 54TWFDmGi
} F/p1?1M
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publicList getItems(){ F{7
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return items; L7(.dO0C
} F3Da-6T@
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publicvoid setItems(List items){ 1uA-!T*e>
this.items = items; Cx(HsJ!,
} JPT&!%~
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publicint getPageSize(){ Sqmjf@o$>
return pageSize; Y%]g,mG
} 6~s{HI!
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publicvoid setPageSize(int pageSize){ ?&1%&?cg9
this.pageSize = pageSize; rSW{1o'
} SFsT^f<
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publicint getTotalCount(){ G~*R6x2g
return totalCount; YWi Y[
} CSm(yB{|pC
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publicvoid setTotalCount(int totalCount){ 5HvYy
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if(totalCount > 0){ Xe/7rhov
this.totalCount = totalCount; 95D(0qv
int count = totalCount / x5U;i
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pageSize; #&{)`+!"
if(totalCount % pageSize > 0) 7#*O|t/'
count++; u |$GOSD
indexes = newint[count]; !a'{gw
for(int i = 0; i < count; i++){ \4*i;a.kU
indexes = pageSize * ke +\Z>BWN
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} 4HXNu, T'
}else{ [vdC $9z,
this.totalCount = 0; Dp@m"_1`+
} a5@lWpQsV
} 9x8Ai
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publicint[] getIndexes(){ }LZz"b<aw
return indexes; 0b,{4DOD
} {`L,F
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publicvoid setIndexes(int[] indexes){ 1tpt433
this.indexes = indexes; .N#grk)C
} zq#gf
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publicint getStartIndex(){ zfml^N
return startIndex; gp{P _
} mA3yM#
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publicvoid setStartIndex(int startIndex){ (jE[W:
if(totalCount <= 0) VD=F{|^
this.startIndex = 0; n6IN I~,
elseif(startIndex >= totalCount) h&{>4{
this.startIndex = indexes xoE,3Sn
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[indexes.length - 1]; ,76nDXy`
elseif(startIndex < 0) cC,gd\}M
this.startIndex = 0; yLt?XhRlp
else{ ]b&qC
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this.startIndex = indexes e=Kr>~q=
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[startIndex / pageSize]; )jRaQ~Sm
} q]*:RI?wGT
} BQ~&gy{
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publicint getNextIndex(){ w{ x=e
int nextIndex = getStartIndex() +
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pageSize; j7Lw(AJ
if(nextIndex >= totalCount) lGX_5R
return getStartIndex(); =Sn!'@%U]
else F8Z6Ss|v3
return nextIndex; TUd=qnu
} W}oAgUd
SRk-3 :
publicint getPreviousIndex(){ X_I.f6v{
int previousIndex = getStartIndex() - #+P)X_i`
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pageSize; ( e(<4-&
if(previousIndex < 0) %G~%:uJ5
return0; gB#$"mq,
else y
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return previousIndex; ;0++):30V
} ;,LlOR
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} uwb>q"M
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抽象业务类 DcLx[C
java代码: C[(Exe
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/** 6~Xe$fP(
* Created on 2005-7-12 ?x
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*/ \LW
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package com.javaeye.common.business; [PW*|U
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import java.io.Serializable; 0bk094
import java.util.List; .:s**UiDR
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import org.hibernate.Criteria; F%QVn.
import org.hibernate.HibernateException; Ndx ]5
import org.hibernate.Session; 4;d9bd)A
import org.hibernate.criterion.DetachedCriteria; .W%{j()op
import org.hibernate.criterion.Projections; |"a%S,I'
import o%tvwv
<El6?ml@
org.springframework.orm.hibernate3.HibernateCallback; +hS}msu'
import TXQY&7
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org.springframework.orm.hibernate3.support.HibernateDaoS x:Kca3p v_
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upport; EGyQhZ mO
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import com.javaeye.common.util.PaginationSupport; #fYz367>
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public abstract class AbstractManager extends F/w!4,'<?5
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HibernateDaoSupport { sL tsvH#
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privateboolean cacheQueries = false; SuW_[6]
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privateString queryCacheRegion; Hv1d4U"qM
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publicvoid setCacheQueries(boolean X/nb7_M
T=2 91)@
cacheQueries){ iwfv t^
this.cacheQueries = cacheQueries; b-+iL
} `+QrgtcEy4
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publicvoid setQueryCacheRegion(String PF-
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queryCacheRegion){ l$Y7CIH
this.queryCacheRegion = %-:6#bz
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queryCacheRegion; Piz/vH6M}
} d+fig{<b
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publicvoid save(finalObject entity){ `r iK[@
getHibernateTemplate().save(entity); ( UV8M\
} s?5(E}
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publicvoid persist(finalObject entity){ \^3\_T&6
getHibernateTemplate().save(entity); -U=bC
} mOyBSOad4
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publicvoid update(finalObject entity){ Bf F$
getHibernateTemplate().update(entity); F/}PN1#T
} jfHVXu^M
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publicvoid delete(finalObject entity){ PhM3?$
getHibernateTemplate().delete(entity); nK6{_Y>
} C(_xqn
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publicObject load(finalClass entity, 7{XI^I:n
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finalSerializable id){ I"9S
return getHibernateTemplate().load !UlG!820
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(entity, id); [3rvRJ.
} 8fJ- XFK$:
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publicObject get(finalClass entity, y:Qo:Z~
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finalSerializable id){ Ut8yA"Y~
return getHibernateTemplate().get ?E2/
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(entity, id); #Gs] u
} 5"6Y=AuQ6
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publicList findAll(finalClass entity){ l>S~)FNwXJ
return getHibernateTemplate().find("from ;Zc(qA
$q{-)=-BXQ
" + entity.getName()); rRL:]%POT
} qI"@ PI!s
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publicList findByNamedQuery(finalString Ah28D!Gor
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namedQuery){ xO6)lVd
return getHibernateTemplate zD-.bHo>.
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().findByNamedQuery(namedQuery); =g$%.
} 9#.nNv*z3
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publicList findByNamedQuery(finalString query, ED @9,W0
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finalObject parameter){ =ex71qj)
return getHibernateTemplate NS;,(v{*N
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().findByNamedQuery(query, parameter); uG2Hzav
} O[;>Y'zqC%
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publicList findByNamedQuery(finalString query, a}+|2k_
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finalObject[] parameters){ x\GCsVy
return getHibernateTemplate f 6Bx>lh
; 7[5%xM
().findByNamedQuery(query, parameters); `TOm.YZG
} *obBo6!zM
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publicList find(finalString query){ &mKtW$K` q
return getHibernateTemplate().find EV z>#GC
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4
(query); 4WZ:zr N
} 1pVagLlb:7
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publicList find(finalString query, finalObject Uoh!1_oV
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parameter){ YUat}-S
return getHibernateTemplate().find ne4hR]:
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(query, parameter); 9^<t0oY
} S
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* f=H#
public PaginationSupport findPageByCriteria 1j
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I1S*=^Z_U
(final DetachedCriteria detachedCriteria){ DDyeNuK
return findPageByCriteria V.6h6B!vB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %:sQ[^0
} oEd+
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public PaginationSupport findPageByCriteria >fPa>[_1
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(final DetachedCriteria detachedCriteria, finalint +ZEj(fd9
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startIndex){ Lf{9=;
return findPageByCriteria /mX/
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(detachedCriteria, PaginationSupport.PAGESIZE, ]
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startIndex); #!l\.:h%
} V<Q''%k
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public PaginationSupport findPageByCriteria V6B`q;lA
) RS*MEgA
(final DetachedCriteria detachedCriteria, finalint qI"Xh"
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pageSize, Stq&^S\x69
finalint startIndex){ qR/~a
return(PaginationSupport) DpH+lpC
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getHibernateTemplate().execute(new HibernateCallback(){ oW3j|V
publicObject doInHibernate I{U7BZy
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(Session session)throws HibernateException { D]\of#%T
Criteria criteria = FCnOvF65
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detachedCriteria.getExecutableCriteria(session); ZgK[,<2
int totalCount = xr}3vJ7
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((Integer) criteria.setProjection(Projections.rowCount iqm]sC`
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()).uniqueResult()).intValue(); mD<- <]SYp
criteria.setProjection T^> ST
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(null); PTrKnuM\J_
List items = <fg~+{PA&
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criteria.setFirstResult(startIndex).setMaxResults 7ESSx"^B
F_.rLgGY
(pageSize).list(); CT,P Q
PaginationSupport ps = GdHFgxI
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new PaginationSupport(items, totalCount, pageSize, ^S:S[0\,
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startIndex); ix2V?\
return ps; `Y>'*4a\
} *:S_v.Y3"
}, true); vqO d`_)
} DSjEoWj
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public List findAllByCriteria(final
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SO @d\H
DetachedCriteria detachedCriteria){ (iQ<
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return(List) getHibernateTemplate 0z&]imU
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().execute(new HibernateCallback(){ .aS`l~6
publicObject doInHibernate KUJCkwQ
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(Session session)throws HibernateException { Rp.42v#ck
Criteria criteria = czNi)4x
\#Md3!MG
detachedCriteria.getExecutableCriteria(session); 2%4u/
return criteria.list(); o;#:%
} lTb4quf8I
}, true); ymH>]
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} m1bkY#\ U|
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public int getCountByCriteria(final j.=&qYc0"
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DetachedCriteria detachedCriteria){ ]R%[cr
Integer count = (Integer) s0r::yO
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getHibernateTemplate().execute(new HibernateCallback(){ Wh).%K(t
publicObject doInHibernate /LwS|c6}}
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(Session session)throws HibernateException { tb$I8T
Criteria criteria = |wbXu:
uuHg=8(
detachedCriteria.getExecutableCriteria(session); EzII!0 F
return 0?V{u`*
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criteria.setProjection(Projections.rowCount mIW8K
):
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()).uniqueResult(); ^IQtXae6M
} DVJuX~'|!
}, true); gq%U5J"x;J
return count.intValue(); ?D>%+rK8c
} `JQw]\f4>
} i~Q nw-^B
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用户在web层构造查询条件detachedCriteria,和可选的 ]@Z[/z%~04
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 oYx4+xH/
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p
PaginationSupport的实例ps。 --OAsbr
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ps.getItems()得到已分页好的结果集 Jb/VITqN4
ps.getIndexes()得到分页索引的数组 @LSfP
ps.getTotalCount()得到总结果数 B:)PUBb
ps.getStartIndex()当前分页索引 P5Bva
ps.getNextIndex()下一页索引 G*s5GG@Z.
ps.getPreviousIndex()上一页索引 SI`ems{1>c
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 g3|k-
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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 h
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一下代码重构了。 Vp$<@Y
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我把原本我的做法也提供出来供大家讨论吧: G^ShN45
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首先,为了实现分页查询,我封装了一个Page类: VwN=AFk
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java代码: \h>6k
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/*Created on 2005-4-14*/ x)R1aq
package org.flyware.util.page; y(<+=
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/** o,rK8x
* @author Joa <=~*`eWV
* GX+Gqj.
*/ %)ri:Q q
publicclass Page {
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/** imply if the page has previous page */ 42f\]R,
privateboolean hasPrePage; TO&^%d
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/** imply if the page has next page */ M1z ?E@kz
privateboolean hasNextPage; <<DPer2
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fn
/** the number of every page */ P^aNAa
privateint everyPage; j];#=+
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/** the total page number */ ZU$QwI8
privateint totalPage; ep6V2R
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/** the number of current page */ i"0*)$
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privateint currentPage; lSfPOx;*
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/** the begin index of the records by the current }S"qU]>8a
hbe";(
query */ _WGWU7h
privateint beginIndex; vL#I+_ 2
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/** The default constructor */ >u\'k+=
public Page(){ \WqC^Di
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} B?db`/G9
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/** construct the page by everyPage $0cE iq?Hf
* @param everyPage e= XC$Jv
* */ $azK M,<q
public Page(int everyPage){ _1jbNQa
this.everyPage = everyPage; aI>F8R?
} !gL1
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, -k
}LW4
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int everyPage, int totalPage, %(S!/(LWW
int currentPage, int beginIndex){ ]|N"jr?7H
this.hasPrePage = hasPrePage; RA!8AS?
this.hasNextPage = hasNextPage; 4av
this.everyPage = everyPage; ^jXKM!}-E
this.totalPage = totalPage; `46|VQAx
this.currentPage = currentPage; KGf@d*ZOMz
this.beginIndex = beginIndex; k$.l^H u
} {z9,CwJan?
I* PxQ
/** Uw?25+[b
* @return yO/'}FD
* Returns the beginIndex. g7w#;E
*/ o4^#W;%w
publicint getBeginIndex(){ BC85#sbl
return beginIndex; I-Q(kWc
} L<G6)'5W
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/** (S?qxW?
* @param beginIndex M<x><U#]A
* The beginIndex to set. t]{, 7.S
*/ y#P_ }Kfo
publicvoid setBeginIndex(int beginIndex){ E*yot[kj
this.beginIndex = beginIndex; k!T-X2L=
} [,Y;#;
7CCSG{k
/** a
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* @return Abpzf\F
* Returns the currentPage. kaRjv
*/ *c(J4
publicint getCurrentPage(){ s]HJcgI
return currentPage; Gx|/
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} #4AqWyp#f
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/** ?btX&:j2P
* @param currentPage ti<;>P[4
* The currentPage to set. AHT(Z~C
*/ b%X<'8z9Z
publicvoid setCurrentPage(int currentPage){ R0yp9icS
this.currentPage = currentPage; _$mS=G(
} :4>LtfA
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/** ?i\$U'2*z3
* @return }5d|y*
* Returns the everyPage. :2lM7|@/
*/ EkOn Rm_hn
publicint getEveryPage(){ dCWq~[[
return everyPage;
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} _AiGD
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/** h2aO-y>K
* @param everyPage ?#:!!.I:
* The everyPage to set. L(/wsw~y*
*/ [3]h(D
publicvoid setEveryPage(int everyPage){ (#Xgfb"S3
this.everyPage = everyPage; TrVQ]9;jWk
} 6f
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/** i;J*9B_U
* @return rD>q/,X=\
* Returns the hasNextPage. <2\QY
*/ 2~)q080jh
publicboolean getHasNextPage(){ _2<k,Dl;RY
return hasNextPage; P!/:yWd
} WWA!_
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/** Lf,C50
* @param hasNextPage 3UcOpq2i\
* The hasNextPage to set. UvGX+M,z'
*/ CasFj9,
publicvoid setHasNextPage(boolean hasNextPage){ hw&~OJeo
this.hasNextPage = hasNextPage; tY?evsVgz
} 6}_J;g\|
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/** >kV=h?]Y
* @return H"rIOoxf
* Returns the hasPrePage. Bs-MoT!
*/ ."j*4
publicboolean getHasPrePage(){ ZQ~EaI9R
return hasPrePage; .a|ROjd!
} XOzZtt
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/** 1gH>B5`
* @param hasPrePage Byns6k
* The hasPrePage to set. p{JE@TM
*/ 3UGdXufw
publicvoid setHasPrePage(boolean hasPrePage){ 5{#ya2
this.hasPrePage = hasPrePage; -PHqD
} gjy:o5{vA*
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/** 7=4V1FS6i
* @return Returns the totalPage. j,g.Eo
* j"<F?k@`Q
*/ [u8JqX
publicint getTotalPage(){ V[">SiOg
return totalPage; 1L.yh U\
} +C(/.X
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/** W.<I:q`eO
* @param totalPage J]Qbg7|
* The totalPage to set. [M:BJ%*
*/ D^2yP~(
publicvoid setTotalPage(int totalPage){ +|Qe/8Q
this.totalPage = totalPage; !'%`g,,r
} o
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} qCYXkZ%`
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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 >l!DWi6
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个PageUtil,负责对Page对象进行构造: _qhYG1t
java代码: ,9ZN k@q
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/*Created on 2005-4-14*/ Y&`nB,'
package org.flyware.util.page; qXQ7Jg9
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import org.apache.commons.logging.Log; o*|j}hnbv
import org.apache.commons.logging.LogFactory; }Gm/9@oKc
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/** <o\I C?A
* @author Joa =Qw`F0t
* sMAu*
*/ =ZN~*HLl}
publicclass PageUtil { ]+i~Cbj
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privatestaticfinal Log logger = LogFactory.getLog VBI~U?0
b$'}IWNV
(PageUtil.class); a(`@u&]WZ
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/** .TetN}w
* Use the origin page to create a new page SiQszV.&
* @param page ~m.@{Do0p
* @param totalRecords <lwkjt=RV
* @return khtSZ"8X
*/ j]5bs*G
publicstatic Page createPage(Page page, int F]~>qt<ia
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totalRecords){ uvf}7
return createPage(page.getEveryPage(), O9]+Jd4W
(lVHKg&U[
page.getCurrentPage(), totalRecords); m339Y2%=
} -V)DKf"f
-:o4|&g<*
/** P ||:?3IH
* the basic page utils not including exception 2hI|]p
*R6Ed
handler K0O&-v0"1
* @param everyPage rSvQarT
* @param currentPage &?#G)suP
* @param totalRecords /a!M6:,pX
* @return page i>68gfx
*/ .0>2j(
publicstatic Page createPage(int everyPage, int Sq,x57-
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currentPage, int totalRecords){ rt[w
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everyPage = getEveryPage(everyPage); %Cz&7 qf"
currentPage = getCurrentPage(currentPage); |[}!E/7>b
int beginIndex = getBeginIndex(everyPage, yk|<P\
fSFb)+
currentPage); g",htYoEnj
int totalPage = getTotalPage(everyPage, [~<X|_LG
U6@Hgi>
totalRecords); 69$[yt>KYz
boolean hasNextPage = hasNextPage(currentPage, hln.EAW'Yc
i#Y[I"'
totalPage); mew,S)dq!
boolean hasPrePage = hasPrePage(currentPage); 9c@."O`
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returnnew Page(hasPrePage, hasNextPage, LJAqk2k
everyPage, totalPage, D-tm'APq
currentPage, (/r l\I
&6`h%;a/&
beginIndex); [Q2"OG@Q
} E9IU,P6a
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privatestaticint getEveryPage(int everyPage){ r{T}pc>^
return everyPage == 0 ? 10 : everyPage; k_hV.CV
} BB694
:q0TS>l
privatestaticint getCurrentPage(int currentPage){ j r<`@
return currentPage == 0 ? 1 : currentPage; jLRh/pbz4
} [Grd?mc#
%|:Gn) 8
privatestaticint getBeginIndex(int everyPage, int OJGEX}3'
`"/s," c:D
currentPage){ *+ql{\am4N
return(currentPage - 1) * everyPage; ?B"k9+%5ej
} ""JTU6]MS
R>iRnrn:-
privatestaticint getTotalPage(int everyPage, int tJ
NJS
#~(VOcRI
totalRecords){ ? %9-5"U[
int totalPage = 0; AUm"^-@x#>
c05kHB$O
if(totalRecords % everyPage == 0) .BR2pf|R
totalPage = totalRecords / everyPage; Wz~=JvRHh
else s?8vs%(l
totalPage = totalRecords / everyPage + 1 ; .I"Qu:``
0'IV"eH2
return totalPage; (|EnRk-E
} a9ko3L
4Y)rgLFj
privatestaticboolean hasPrePage(int currentPage){ *,:>EcDr
return currentPage == 1 ? false : true; q*|H*sS
} Sd!!1as
#JFTD[1
privatestaticboolean hasNextPage(int currentPage, 3$u3ssOL
Nm.H
int totalPage){ K\7\
return currentPage == totalPage || totalPage == [<+A?M=
5v f?E"\r
0 ? false : true; Vy:I[@6@+
} rfgkw
l$PSID
^]&uMkPN
} )]/gu\90
kPm{ tc
ETw7/S${
hGPo{>xR
o"te7nBI
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。 "%o,P/<X
:ub 4p4h*
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 OD*\<Sc
csceu+IA
做法如下: ;#F/2UgHB
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 -K 7jigac
llCBqWn
的信息,和一个结果集List: b'!t\m
java代码: OlW|qj
''{REFjK7
vr,8i7*0
/*Created on 2005-6-13*/ [z2XK4\e1T
package com.adt.bo; bjQp6!TsZ
u?(@hUV.
import java.util.List; TY(B]Q_o
raWs6b4Q
import org.flyware.util.page.Page; ^PnXnH?
r\OunGUP
/** WIe7>wkC
* @author Joa cBZKt
*/ 4GA9oLl
publicclass Result { $>PXX32
qqL :#]lV5
private Page page; #JmVq-)
9Q~9C9{+
private List content; M bj{C
,g.*Mx`-
/** xJphG
* The default constructor O%g
Q
*/ a'T8U1
public Result(){ `&\jOve
super(); 1ZL91'U
} ~$I9%z7@
WrA!'I
/** uwQ~4
* The constructor using fields PQl^jS
* lO
(MF
* @param page U9<AL.
* @param content <G9HVMiP
*/ ))/NGa
public Result(Page page, List content){ ',7LVT7
this.page = page; eGwO!Lv}B
this.content = content; Mnu8d:$
} pyvH [
Z~g6C0
/** p<eu0B_V
* @return Returns the content. "!V-@F$@N
*/ R`[jkJrc
publicList getContent(){ B]KR *
return content; {iGy@?d)zt
} aVg~/
Dq [f
/** F@8G,$
* @return Returns the page. N('=qp9
*/ [>2iz
public Page getPage(){ s6q6)RD"
return page; I_1(jaY
} I7@|{L1|FB
jR1o<]?
/** u|ph_?6o
* @param content 1zGD~[M
* The content to set. O$qxo
&
*/ C+0MzfLgf
public void setContent(List content){ J!{t/_aw
this.content = content; eD|p1+76
} YiO3.+H
i/vo
/** 2
c
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* @param page 8a,uM :
* The page to set. ]u]BxMs
*/ Y3_C':r
publicvoid setPage(Page page){ %Z8'h\|
this.page = page; w#XD4kwQG
} ]C;X/8'Jf5
} x%v[(*F#y
e3#0r
%E R"Udh
a2!U9->!
-JEiwi ,
2. 编写业务逻辑接口,并实现它(UserManager, J~]Y
|)+ s, LT5
UserManagerImpl) tJM#/yT
java代码: =bBV
A0y
NihUCj"
!K8Kw
W|X
/*Created on 2005-7-15*/ wD\viuq0
package com.adt.service; >1}@Q(n/}{
o2 ;
import net.sf.hibernate.HibernateException; 9-W3}4'e
eh39"s
import org.flyware.util.page.Page; 0.aIcc
]\C wa9
import com.adt.bo.Result; tD~
nPbbB
2 rFjYx8D!
/** ]
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* @author Joa t/wo
G9N
*/ qkM)zOZ^
publicinterface UserManager { g@O H,h/
E0*KKo%
public Result listUser(Page page)throws q4EOI
:`>$B?x+
HibernateException; k-Z:z?M
f7SMO-3a
} e7Sp?>-d
"5!T-Z+F
\{a!Z&df
6!`GUU
n)Z u>
java代码: 45,): U5
&RHZ7T
:#VdFMC<
/*Created on 2005-7-15*/ >T#" Im-
package com.adt.service.impl; !X[P)/?b0+
,Y4>$:#n/
import java.util.List; UhKd o
d =p=eUd2
import net.sf.hibernate.HibernateException; Nz77"
kC
dq{+-XaEk
import org.flyware.util.page.Page; 7>E>`Nc6
import org.flyware.util.page.PageUtil; GGs7]mhA
Z[9t?ePL
import com.adt.bo.Result; i'QR-B&Z
import com.adt.dao.UserDAO; .iC!Ttr
import com.adt.exception.ObjectNotFoundException; N/!(`Z,
import com.adt.service.UserManager; ]$,3vYBf
oF~+L3&X
/** :4r{t?ytXw
* @author Joa a&Z,~Vp
*/ 8og8;#mnyr
publicclass UserManagerImpl implements UserManager { q@^^jlHP
9SBTeJ$RZ
private UserDAO userDAO; K(uz`(5
X<D fzd oI
/** 8wrO64_NO
* @param userDAO The userDAO to set. Bp_8PjQ
*/ rE Me=>^
publicvoid setUserDAO(UserDAO userDAO){ `6P2+wf1j~
this.userDAO = userDAO; aX2N
Qq>s
} R.\]JvqO
1=h5Z3/fj
/* (non-Javadoc) iR!]&Oh
* @see com.adt.service.UserManager#listUser c{IL"B6>
zm{`+boH<
(org.flyware.util.page.Page) =axuL P))
*/ t#VX#dJ
public Result listUser(Page page)throws 5WA:gy gB&
/9A6"Z
HibernateException, ObjectNotFoundException { 5\EnD,y
int totalRecords = userDAO.getUserCount(); R,s}<N$
if(totalRecords == 0) kTcW=AXu
throw new ObjectNotFoundException |[0Ijm2
6V"uovN2
("userNotExist"); T/.U Mw
page = PageUtil.createPage(page, totalRecords); O^!Bc}$
List users = userDAO.getUserByPage(page); (hBph+
returnnew Result(page, users); o`Af6C;Q
} Qo!F?i/ n
:-WNw
n
} 2q(gWhcj
44s 9\
8`wKq6
WD_{bd)
yEos$/*u-N
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |~ytAyw
dC;&X
g`
询,接下来编写UserDAO的代码: ts%
n tnvI
3. UserDAO 和 UserDAOImpl: &Dt=[yqeG
java代码: m] yUcj{F
.^2.h
ZXN`8!]&
/*Created on 2005-7-15*/ `-e9#diQe
package com.adt.dao; ^s#+`Y05/
BNF*1JO
import java.util.List; 6oq5CD oq
gj
iFpW4
import org.flyware.util.page.Page; ACy}w?D<
>9mj/P D
import net.sf.hibernate.HibernateException; ]imVIu
d'&OEGb<
/** ;B;@MD,B
* @author Joa [W*M#00_&4
*/ d&AO4^
publicinterface UserDAO extends BaseDAO { ^<Gxip
A|4om=MO
publicList getUserByName(String name)throws 3AglvGK7{
a~J!G:(
HibernateException; 5}Id[%.x
;5.<M<PH
publicint getUserCount()throws HibernateException; ?PS?_+E\L
Lq$ig8V:O7
publicList getUserByPage(Page page)throws yMu G? x+
(7N!Jvg9
HibernateException; _BY+Tfol
z]SEPYq:
} zRd.!Rv
R?;mu^B
"G~!J\
pKpB
"O-X*>?f
java代码:
EADN
#t;]s<
xMNQT.A
/*Created on 2005-7-15*/ O9zMD8
package com.adt.dao.impl; Dn@ZS _f
!H@HgJ
-
import java.util.List; =+UtAf<n
`"}).{N]C
import org.flyware.util.page.Page; uY(8KW
@87Y/_l
import net.sf.hibernate.HibernateException; W!R0:-
import net.sf.hibernate.Query; :<bhQY
|O6/p7+.
import com.adt.dao.UserDAO; M)!"R [V
$./aKJ1B
/** FNuE-_
* @author Joa kX+9U"`
C
*/ :*&c'
public class UserDAOImpl extends BaseDAOHibernateImpl `"[qb ?z
,`RX~ H=C
implements UserDAO { n?$c"}
Ynvf;qs
/* (non-Javadoc) ]Ml
* @see com.adt.dao.UserDAO#getUserByName )XavhS~Ff
NJE*/_S
(java.lang.String)
6WT3-@d
*/ TE$6=;
publicList getUserByName(String name)throws ZfX$q\7
UimofFmI%
HibernateException { J _dgP[
String querySentence = "FROM user in class {J
izCUo_'
3N-pND0>p
com.adt.po.User WHERE user.name=:name"; $[Z~BfSQ
Query query = getSession().createQuery 2"?D aX
2C}Yvfm4
(querySentence); %cg| KB"l
query.setParameter("name", name); .{c7 I!8
return query.list(); =]-z?O6^`
} ye=4<b_
A-:k4] {%P
/* (non-Javadoc) KpYezdPF)
* @see com.adt.dao.UserDAO#getUserCount() @XolFOL"f"
*/ `_ 1~[t
publicint getUserCount()throws HibernateException { >V?0#f45@
int count = 0; h'};spv
String querySentence = "SELECT count(*) FROM B~ i
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user in class com.adt.po.User"; D-LOjMe
Query query = getSession().createQuery I=#`8deH(
z`t~N
(querySentence); NJ.oM E@=
count = ((Integer)query.iterate().next ,8Po
_[
.l_Nf9=
()).intValue(); p*,T~(A6
return count; ssx#|InY
} B7[d^Y60B
&nXE?-J
/* (non-Javadoc) ObEz 0Rj
* @see com.adt.dao.UserDAO#getUserByPage z2t+1In,
hXth\e\[{`
(org.flyware.util.page.Page) jzJTV4&zjs
*/ mN}szW,
publicList getUserByPage(Page page)throws {eI'0==
t4#gW$+^?H
HibernateException { r!dWI
String querySentence = "FROM user in class .!KsF
h,pK
qE[YZ(/f0&
com.adt.po.User"; vs=q<Uw)
Query query = getSession().createQuery "lw|EpQk`
|&JeJ0k>~
(querySentence); }}$@Tij19[
query.setFirstResult(page.getBeginIndex()) Znb7OF^#"
.setMaxResults(page.getEveryPage()); jhf3(hx&F
return query.list(); p>+9pxx~U
} xmcZN3 ){+
vio>P-2Eho
} f\dfKNm6
v.Q#<@B^:
^_|kEvk0
Jg[Ao#,==
N4C7I1ihq
至此,一个完整的分页程序完成。前台的只需要调用 =n"k gn
|EX=Rj*
userManager.listUser(page)即可得到一个Page对象和结果集对象 KH;~VR8"/
i,*m(C@F}
的综合体,而传入的参数page对象则可以由前台传入,如果用 9;U?_
t kj
webwork,甚至可以直接在配置文件中指定。 Y /_CPY
LZe)_9$
下面给出一个webwork调用示例: &Q~W{.
java代码: iOURS
w'(/dr
+m%%Bz>
/*Created on 2005-6-17*/ Icrnu}pl_
package com.adt.action.user; N7J?S~x
8^ f: -5
import java.util.List; %r(WS_%K|
)e?&'wa>
import org.apache.commons.logging.Log; lUs$I{2_
import org.apache.commons.logging.LogFactory; j0mN4Ny
import org.flyware.util.page.Page; i)|jLrW~e
R*D<M3
import com.adt.bo.Result; }l7+W4~
import com.adt.service.UserService; rl%,9JD!
import com.opensymphony.xwork.Action; H/*ol^X7
X n!mdR
/** O[ird`/
* @author Joa - /\qGI
*/ ;z4F-SYQ
publicclass ListUser implementsAction{ "g^i%
zk8)!Af
privatestaticfinal Log logger = LogFactory.getLog {s0%XG1$
Y\-xX:n.\
(ListUser.class); UrvUt$WO
dz9U.:C
private UserService userService; Z{0BH{23
f+ceL'fr
private Page page; 8-nf4=ll
~%/Rc`
privateList users; zg<-%r'$
.
|T=T0^
/* B]"`}jn
* (non-Javadoc) ^_bG{du
* `sCaGCp
* @see com.opensymphony.xwork.Action#execute() ,-y9P
*/ XJ4f;U
publicString execute()throwsException{ NVv
<vu
Result result = userService.listUser(page); YK3>M"58
page = result.getPage(); wI_@
users = result.getContent(); f"5O'QHGQK
return SUCCESS; LN5LT'CE
} DYr#?} 40
4@?0wV
/** Ocx"s\q(
* @return Returns the page. j1K3|E
*/ w'H'o!*/
public Page getPage(){ l:V
R8g[
return page; F(HfXY3
} >s{I@#9
D9oNYF-V
/** :*''ci
* @return Returns the users. \#9LwC"8;
*/ 9b+jT{Tg
publicList getUsers(){ ]^~}/@
return users; 2nB99L{6
} e,p"=/!aY
^&eF916H
/** ,@ 8+%KqG
* @param page (gBKC]zvz3
* The page to set. FXof9fa_B
*/ YJ _eE
publicvoid setPage(Page page){ C$y6^/7)
this.page = page; YvU%OO-+,
} cJ96{+
p`Pa;=L
/** ~$HB}/
* @param users Y_'ERqQ
* The users to set. m@2E ~m
*/ \cIN]=#
publicvoid setUsers(List users){ gpV4qDXV
this.users = users; EjR(AqZY
} Uk?G1]$mL
uYUFxm
/** XQ]K,# i
* @param userService Yr9'2.%Q
* The userService to set. y*i&p4Y*
*/ 2zBk#c+
publicvoid setUserService(UserService userService){ J6Z[c*W
this.userService = userService; 2Xt4Rqk $
} u;`]U$Qq9
} OpUfK4U)
bWswF<y-
)/;KxaKt
p/h\QG1
Y
[`+7w
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, .q@?sdGD
&BVHQ7[
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Lzh8-d=HQ
}@r23g%
么只需要: gmL~n7m:K
java代码: hw
DxGiU
fq7#rZCxX
"Oxr}^% i
<?xml version="1.0"?> hLO)-ueb
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork yE$PLM
R}&?9tVRR
1.0//EN" "http://www.opensymphony.com/xwork/xwork- :;k?/KU7
PF{uaKWk
1.0.dtd"> )(}[S:`
ZoG@"vr2
<xwork> 9c>i>Vja!
zwfft
<package name="user" extends="webwork- HXLnjXoe
6>vR5pn
interceptors"> FOTe,F.8
C(N'=-;Kl
<!-- The default interceptor stack name %rW}x[M%w?
my'nDi
--> "<CM'R
<default-interceptor-ref F\:~^`
|a(KVo
name="myDefaultWebStack"/> LE\*33k_
(Z),gxt
<action name="listUser" /UCBoQ$/]
?JrUZXY
class="com.adt.action.user.ListUser"> ~MG6evm &
<param 42Z:J 0
|9E:S
name="page.everyPage">10</param> 8em'7hR9
<result L AQ@y-K3
/JD}b[J$
name="success">/user/user_list.jsp</result> wLV,E,gM
</action> ng1E'c]0@
k<9,Ypa
</package> "- 4|HA
_H+]G"k/r
</xwork> x@-K
5aQ)qUgAW
Ua1&eCZi
'P.y?
S<mZs;
,1-%C)
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 Y+-yIMt$r
o|xf2k
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 2I.FSR_G?
` H'G"V
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 TFSdb\g
#7uH>\r
+25}X{r$_
#VQZ"7nI@
VfnL-bDGV
我写的一个用于分页的类,用了泛型了,hoho W|PAI[N
j=0kxvp
java代码: l)u%`Hcn
|IAx!Z-P
ndSu-8?L
package com.intokr.util; E>fY,*0
nW=6nCyvo
import java.util.List; x;mw?B[
9{pT)(Wnb
/** 8lF9LZ8
* 用于分页的类<br> }QE.|.fA1
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;}B=g/C
* m$8siF{<q
* @version 0.01 #qd!_oN
* @author cheng >tg)F|@
*/ 4H8r[
public class Paginator<E> { (Jq m9
privateint count = 0; // 总记录数 5_^d3LOT0x
privateint p = 1; // 页编号 i\xs!QU
privateint num = 20; // 每页的记录数 hb[ThQ
privateList<E> results = null; // 结果 ?$pNd uE
@nH3nn
/** w-).HPe
* 结果总数 jFQ y[k-B
*/ !'$*Z(
publicint getCount(){ frcAXh9
return count; bJ2-lU% ;2
} ]OpGD5jZ
KloX.y)q
publicvoid setCount(int count){ xW"O|x$6
this.count = count; S^s-md>
} Ar%*NxX
M6-uTmN:d
/** $QiMA,
* 本结果所在的页码,从1开始 p{E(RsA
* 1d<?K7%^
* @return Returns the pageNo. !.h{/37]
*/ ruaZ(R[
publicint getP(){ >MYxj}I4{z
return p; H{cOkuy
} FK BRJ5O
-Mo4`bN
/** |q4=*X q
* if(p<=0) p=1 g$Tsht(rHD
* .-$3I|}X=
* @param p /KH85/s
*/ b^R:q7ea
publicvoid setP(int p){ C:1(<1K
if(p <= 0) a`Bp^(f}
p = 1; AO<T6VK
this.p = p; dV$[O`F*b
} a" s2N%{
091m$~r*
/** 60{G
4b)
* 每页记录数量 5Sl"1HL
*/ -zECxHjx
publicint getNum(){ CH7a4qL`
return num; AMrYT+1
} :[a*I6/^
cc${[yj)
/** j+!u=E
* if(num<1) num=1 '@t,G,FJ
*/ w/NT 5
publicvoid setNum(int num){ _;}$/
if(num < 1) } W]A`-Jv
num = 1; zFOtOz`9H
this.num = num; >s%Db<(P=
} fBX@
MedC
%:C6\4
/** a;$V;3C{b&
* 获得总页数 2IJniS=[>
*/ Xau%v5r
publicint getPageNum(){ o?]Q&,tO
return(count - 1) / num + 1; @<DRFP
} &zYQH@
+1#;s!e
/** K^x{rn.Zf
* 获得本页的开始编号,为 (p-1)*num+1 Bc!<!
*/ cLyf[z)W
publicint getStart(){ %lbvK^
return(p - 1) * num + 1; @
2hGkJ-
} B}qG-}(V
~{DJ,(N"n
/** {"jtR<{)
* @return Returns the results. tnpEfi-
*/ IV~)BW leT
publicList<E> getResults(){ C32*RNG?U
return results; f)vnm*&-
} xS,F
DPA
#Q2s3"X[
public void setResults(List<E> results){ .LAB8bg
this.results = results; i:Y5aZc/Ds
} _"*vj-{-y
|i
B#
public String toString(){ ?uCL[
StringBuilder buff = new StringBuilder 3]S_w[Q4
/ 8O=3
(); R?{_Q<17
buff.append("{"); OGEe8Z9Jt
buff.append("count:").append(count); <uU<qO;6
buff.append(",p:").append(p); @nqM#
buff.append(",nump:").append(num);
[<r.M<3
buff.append(",results:").append i&(1<S>P
L0VZ>!*o
(results); H8g6ZCU~
buff.append("}"); .Z]hS7t
return buff.toString(); ;u`8pF!_eE
} !,$K;L
Bor_(eL^
} I_#5gq
uPho|hDp
r5[pT(XT]