Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 C~_q^fXJt
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 c#x7N9;"!
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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|]
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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 0gi}"v
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分页支持类: `#<eA*^g5
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java代码: J\GKqt;5@
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package com.javaeye.common.util; eo]a'J9(
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import java.util.List; 3]7ipwF2q
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; cnYYs d{
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privateint pageSize = PAGESIZE; *fOIq88
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privateList items; ls]Elo8h1f
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privateint totalCount; ]q37 Hj
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privateint[] indexes = newint[0]; =mAGD*NKu
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privateint startIndex = 0; &U854
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public PaginationSupport(List items, int @US '{hO1p
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totalCount){ ,Zr YJ<
setPageSize(PAGESIZE); WVsKrFZT
setTotalCount(totalCount); )/
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setItems(items); 0-lPhnrp
setStartIndex(0); n*Q4G}p
} vLD:(qTi
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public PaginationSupport(List items, int Mj,2\ijNM
e4 ?<GT
totalCount, int startIndex){ ?WMi S]Q\
setPageSize(PAGESIZE); _4!7
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setTotalCount(totalCount); O]4W|WI3
setItems(items); #SK#k<&P
setStartIndex(startIndex); U8U/?zW/&
} #{?m
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public PaginationSupport(List items, int Yoj~|qL
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totalCount, int pageSize, int startIndex){ aB7d(
setPageSize(pageSize); XC57];-
setTotalCount(totalCount); U8Cw7u2
setItems(items); pC55Ec<
setStartIndex(startIndex); zl,bMtQ
} rZb_1E<
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publicList getItems(){ U3(L.8(sA
return items; 8rnb
} )sMAhk|
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publicvoid setItems(List items){ IZzhJK M1V
this.items = items; EgkZ$ah
} Y^T-A}?`
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publicint getPageSize(){ K7n;Zb:BR
return pageSize; F<H`8*q9
} M^0w/
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publicvoid setPageSize(int pageSize){ b0rt.XB
this.pageSize = pageSize; Z5{*? 2
} |F8;+nAVF#
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publicint getTotalCount(){ U1OLI]P
return totalCount; O1l4gduN|i
} Q';\tGy
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publicvoid setTotalCount(int totalCount){ D>,$c
if(totalCount > 0){ DtI%-I.
this.totalCount = totalCount; 2{jtQlc
int count = totalCount / iA5*
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pageSize; HCfS)`
if(totalCount % pageSize > 0) hqwz~Ky}
count++; UEx(~>
indexes = newint[count]; \1eKY^)2
for(int i = 0; i < count; i++){ dn:|m^<)
indexes = pageSize * hVTyv"
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} btr x?k(
}else{ 1o"y%*"
this.totalCount = 0; N9fUlXhR
} QySca(1tN
} R|cFpRe
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publicint[] getIndexes(){ u|:UFz^p
return indexes; 64IeCAMVo
} $j$\ccG
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publicvoid setIndexes(int[] indexes){ f@,hO5h(_|
this.indexes = indexes; >TH-Q[
} OsHkAI
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publicint getStartIndex(){ Ply2DQr
return startIndex; h|$zHm
} _KT]l./
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publicvoid setStartIndex(int startIndex){ A[wxa
if(totalCount <= 0) noB}p4
this.startIndex = 0; _s*uF_:3
elseif(startIndex >= totalCount) ;dpS@;v
this.startIndex = indexes Wr}a\}R
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[indexes.length - 1]; s\n,Z?m
elseif(startIndex < 0) oeRYyJ
this.startIndex = 0; b ?=
else{ 2={K-s20
this.startIndex = indexes 4)c"@Zf
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[startIndex / pageSize]; e!L sc3@
} )PLc+J.I
} l[x`*+ON:2
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publicint getNextIndex(){ 7J)Hwl
int nextIndex = getStartIndex() + %\s#e
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pageSize; JOL Z2
if(nextIndex >= totalCount) !W6
return getStartIndex(); *N&^bF"SF
else 7lBQd (
return nextIndex; F#3$p$;B$
} b;t}7.V'%
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publicint getPreviousIndex(){ FB^dp}
int previousIndex = getStartIndex() - {0m[:af&
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pageSize; Vq;{+j(
if(previousIndex < 0) N5I W@?4
return0; B@~eBU,$
else c] :J/'vc
return previousIndex; c^q O@%s
} VN55!l'OV
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} -`ys pE0?
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抽象业务类 XxrO:$
java代码: NVM2\fs
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/** 'yAoZ P\|
* Created on 2005-7-12 $SD@D6`lL
*/ P.2.Ge|
package com.javaeye.common.business; B39PDJ]hu
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import java.io.Serializable; |^&2zyUj/
import java.util.List; XP
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import org.hibernate.Criteria; Fw8X$SE"
import org.hibernate.HibernateException; 3=eGS
import org.hibernate.Session; My43\p
import org.hibernate.criterion.DetachedCriteria; xQ(KmP2hl
import org.hibernate.criterion.Projections; &,gryBN
import nR|uAw
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org.springframework.orm.hibernate3.HibernateCallback; e]y=]}A3{
import 4m g
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org.springframework.orm.hibernate3.support.HibernateDaoS T_|fb)G+{
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upport; 2K7:gd8Ru
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import com.javaeye.common.util.PaginationSupport; 8"I5v(TV
( ;S]{z%
public abstract class AbstractManager extends C
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HibernateDaoSupport { *Uw#
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privateboolean cacheQueries = false; T>:g
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privateString queryCacheRegion; J$=b&$I(
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publicvoid setCacheQueries(boolean /3:IE%o
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cacheQueries){ ."@a1_F|
this.cacheQueries = cacheQueries; Y_iF$m/R
} e+[J[<8
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publicvoid setQueryCacheRegion(String [T?6~^m=
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queryCacheRegion){ M97p.; ;
this.queryCacheRegion = wP *a>a
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queryCacheRegion; *V<2\-
} 6'lT`E|
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publicvoid save(finalObject entity){ LRlk9:QD>
getHibernateTemplate().save(entity); [A OluS
} M#jee E-}%
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publicvoid persist(finalObject entity){ kQiW 5
getHibernateTemplate().save(entity); ^=M(K ''
} dCJR,},\f
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publicvoid update(finalObject entity){ aRb:.\ \zc
getHibernateTemplate().update(entity); b(rBha|
} 9(gOk
x?&xz;
publicvoid delete(finalObject entity){ we).8%)'
getHibernateTemplate().delete(entity); ?g1.-'
} )o(F*v
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publicObject load(finalClass entity, 4!RI2?4V
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finalSerializable id){ -(,6w?
return getHibernateTemplate().load 1+ARV&bc
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(entity, id); +P;D}1B#I?
} &7nfTc
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publicObject get(finalClass entity, g<5Pc,
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finalSerializable id){ o8pe07n(W
return getHibernateTemplate().get "TNUw&ih
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(entity, id); v-aq".XQ
} C3h!?5
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publicList findAll(finalClass entity){ 8$olP:d
return getHibernateTemplate().find("from HWAqJb [
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" + entity.getName()); W3j|%
} 6df&B
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publicList findByNamedQuery(finalString x5Pt\/ow
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namedQuery){ QQ8W;x
return getHibernateTemplate 2=
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().findByNamedQuery(namedQuery); 1qN9bwRO
} ',%&DA2
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publicList findByNamedQuery(finalString query, ;a)\5Uy
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finalObject parameter){ B)`X7uG
return getHibernateTemplate Br!&Y9
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().findByNamedQuery(query, parameter); qnRzs
} .e+UgCwi
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publicList findByNamedQuery(finalString query, 8;NO>L/J]i
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finalObject[] parameters){ f}!26[_9{
return getHibernateTemplate xxn&{\
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().findByNamedQuery(query, parameters); #4u; `j"4=
} 4e t#Q
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publicList find(finalString query){ NR@Tj]`k
return getHibernateTemplate().find z\5Nni/~6D
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(query); !Esiq<Yh
} +rY0/T_0,
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publicList find(finalString query, finalObject M(jH"u&f
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parameter){ /B7
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return getHibernateTemplate().find }6N|+z.cU
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(query, parameter); G9q0E|
} ?J?!%Mw
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public PaginationSupport findPageByCriteria e8.bH#
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(final DetachedCriteria detachedCriteria){ MzG.Qh'z
return findPageByCriteria kv b-=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7d5x4^EYE
} /K<Nlxcm
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public PaginationSupport findPageByCriteria 0]~n8mB>
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(final DetachedCriteria detachedCriteria, finalint ^D|c
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startIndex){ zL'n
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return findPageByCriteria k5YDqGn'q
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(detachedCriteria, PaginationSupport.PAGESIZE, |M_Bbo@ud
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startIndex); 1<"kN^
} 9E+lriyY
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public PaginationSupport findPageByCriteria ;4IP7$3G
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(final DetachedCriteria detachedCriteria, finalint \m!."~%
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pageSize, urB.K<5ZA
finalint startIndex){ zZHsS$/
return(PaginationSupport) AF-.Nwp
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getHibernateTemplate().execute(new HibernateCallback(){ !@X#{
publicObject doInHibernate o_n.,=/cZ
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(Session session)throws HibernateException { HApP*1J^c
Criteria criteria = w[ngkLEA
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detachedCriteria.getExecutableCriteria(session); ^-_!:7TH]
int totalCount = `ijX9c
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((Integer) criteria.setProjection(Projections.rowCount =`U[{3A_
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()).uniqueResult()).intValue(); n'H\*9t
criteria.setProjection :\Z0^{
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(null); o6R(BMwGa
List items = ^5+-7+-S
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criteria.setFirstResult(startIndex).setMaxResults )C@,mgh
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(pageSize).list(); 4C:YEX~
PaginationSupport ps = Yq_zlxd%F
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new PaginationSupport(items, totalCount, pageSize, {~"=6iyj
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startIndex); +l9avy+P(
return ps; "n:9JqPb
} V4H+m,R
}, true); @b
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} :FSkXe2yy0
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public List findAllByCriteria(final AN;?`AM;
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DetachedCriteria detachedCriteria){ h4#5j'RO
return(List) getHibernateTemplate `6A"eDa
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().execute(new HibernateCallback(){ 1\p[mN
publicObject doInHibernate zSO[f
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(Session session)throws HibernateException { QEPmuG
Criteria criteria = ~"N]%Cu
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detachedCriteria.getExecutableCriteria(session); {e^llfj$#
return criteria.list(); Tla*V#:Ve
} vBp5&*
}, true); ?>_.~b~
} 580t@?
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public int getCountByCriteria(final +CkK4<dF
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DetachedCriteria detachedCriteria){ 9&tV#=s
Integer count = (Integer) 4Zq5
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate oOlI*/OMb
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(Session session)throws HibernateException { JeA}d
Criteria criteria = }oG&zw
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detachedCriteria.getExecutableCriteria(session); 0ePZxOSjD
return ^o 5q- ;a
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criteria.setProjection(Projections.rowCount u{ng\d*KE}
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()).uniqueResult(); Rg6>6.fk*
} 1pK7EK3R
}, true); nxt1Y04,H
return count.intValue(); 7 mN?;X33
} )mEF_ &
} uzo}?X#
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用户在web层构造查询条件detachedCriteria,和可选的 pmS=$z;I
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 n RGH58
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PaginationSupport的实例ps。 >C i=H(8vN
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ps.getItems()得到已分页好的结果集 1a<,/N}}t
ps.getIndexes()得到分页索引的数组 ^2=zp.)
ps.getTotalCount()得到总结果数 Gd"*mLd
ps.getStartIndex()当前分页索引 k5($b{
ps.getNextIndex()下一页索引 *<@
ps.getPreviousIndex()上一页索引 `/U:u9H9v
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @dXf_2Tv=
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 `{/=i|6
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一下代码重构了。 }vi%pfrB
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我把原本我的做法也提供出来供大家讨论吧: TwH(47|?Nt
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首先,为了实现分页查询,我封装了一个Page类: 1/i|
java代码: K.%E=^~q
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/*Created on 2005-4-14*/ UYPBKf]A9
package org.flyware.util.page; MMf6QxYf
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/** =nsY[ s<
* @author Joa <7p2OPD
* \yy!?UlaI
*/ 1w5nBVC*$V
publicclass Page { Ip4~qGJ
LP\ Qwj{
/** imply if the page has previous page */ @6gz)
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privateboolean hasPrePage; o _-t/
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/** imply if the page has next page */ L}9@kjW
privateboolean hasNextPage; c.~|)^OXXO
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/** the number of every page */ iZ:-V8{
privateint everyPage; QIw.`$H+
aql*@8
)m
/** the total page number */ 1a'JNe$
privateint totalPage; &Ls0!dWC
RI`A<*>w
/** the number of current page */ ^R\blJQ<^
privateint currentPage; 4?&=H
*H:
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/** the begin index of the records by the current /i"EVN`t
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query */ bw4b'9cK
privateint beginIndex; 0'~?u '
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Dn@ n:m
/** The default constructor */ o ).pF">jh
public Page(){ U` U/|@6
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} N@VD-}E
5
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/** construct the page by everyPage 52~k:"c
* @param everyPage jPd<h{js
* */ pQ>V]M
public Page(int everyPage){ m/ukH{H1%
this.everyPage = everyPage; c{<3\
} |joGrWv4
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/** The whole constructor */ $?A]!Y;
public Page(boolean hasPrePage, boolean hasNextPage, J
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int everyPage, int totalPage, <(iOzn
int currentPage, int beginIndex){ #:yZJS9f9
this.hasPrePage = hasPrePage; nO/5X>A,Zw
this.hasNextPage = hasNextPage; <@yyx7
this.everyPage = everyPage; vxgm0ZOMN
this.totalPage = totalPage; ~\^8
^
this.currentPage = currentPage; rB)WHx<
this.beginIndex = beginIndex; uZ^i8;i
} L`!sV-.
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/** 9xz`V1mIL
* @return D^u{zZy@e
* Returns the beginIndex. F lZ]R
*/ 2.[qcs3zl
publicint getBeginIndex(){ spI{d!c
return beginIndex; DXiD>1(q
} zf!c
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/** qkEy$[D9
* @param beginIndex gV7o
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* The beginIndex to set. q8D1MEBL`
*/ [brrziZ
publicvoid setBeginIndex(int beginIndex){ @!S$gTz
this.beginIndex = beginIndex; EAI[J&c
} :K~7BJ(HO
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/** iO@wqbg$6
* @return ^Nu} HcC+
* Returns the currentPage. (UM+?]Qwy
*/ ?R+$4;iy
publicint getCurrentPage(){ Jq!($PdA
return currentPage; `Ctj]t
} HlO+^(eX
Ju\"l8[f
/** NX;&V7
* @param currentPage )ad-s
* The currentPage to set. w7C=R8^
*/ o#Y1Uamkf
publicvoid setCurrentPage(int currentPage){ oHYD6qJX{
this.currentPage = currentPage; pg<>Ow5,~l
} ,..b)H5n
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/** 5YCbFk^
* @return jyC6:BNust
* Returns the everyPage. qL#R
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*/ IF}r%%'Y$
publicint getEveryPage(){ t|q=NK/
return everyPage; }>w;
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} d?K8Ygz
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/** 9~_6mR<
* @param everyPage Gl:ASPZ6
* The everyPage to set. OTm`i>rB
*/ r3kI'I|bq
publicvoid setEveryPage(int everyPage){ RoTT%c P_
this.everyPage = everyPage; )t4C*+9<U
} phdN9<Z
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/** fwEi//1
* @return $CmTsnR1#y
* Returns the hasNextPage. (07d0 <<[
*/ "duJl-
publicboolean getHasNextPage(){ {x:IsQZ
return hasNextPage; K+\hv~+@
} r$7rYxFR
P#xn!fMi
/** B]vj1m`9
* @param hasNextPage #59zv=
* The hasNextPage to set. j;3o9!.s:
*/ j7d;1 zB+G
publicvoid setHasNextPage(boolean hasNextPage){ cG?266{g
this.hasNextPage = hasNextPage; B_S3}g<~
} V*aTDU%-.
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/** NO$Nl/XM
* @return #q- _
* Returns the hasPrePage. *E]\l+]J
*/ 2KEww3.{
publicboolean getHasPrePage(){ - \QtE}|4
return hasPrePage; OK 6}9Eu9
} krA))cP
El%(je,|
/** -}J8|gwwp
* @param hasPrePage F\I^d]#,[
* The hasPrePage to set. CmTJa5:
*/ m+g>s&1H
publicvoid setHasPrePage(boolean hasPrePage){ epF>z
this.hasPrePage = hasPrePage; d1-p];&
} 93\,m+-
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9q
/** 4pqZ!@45|
* @return Returns the totalPage. AMdS+(J
* hs4r5[
*/ *C BCQp[$
publicint getTotalPage(){ |>4 { 4
return totalPage; \K6J{;# L
} p!ErH]lH
9:>K!@
/** s,Swlo7D!
* @param totalPage UwU]l17~
* The totalPage to set. UL%ihWq
*/ F?B=:8,}
publicvoid setTotalPage(int totalPage){ #k)\e;,X
this.totalPage = totalPage; fW
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} wk#QQDV3|0
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} ${wE5^ky
R 6Em^A/>
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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 t3G'x1
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个PageUtil,负责对Page对象进行构造: $w\ , ."y
java代码: In&vh9Lw
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/*Created on 2005-4-14*/ `t6L'%\
package org.flyware.util.page; H[
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import org.apache.commons.logging.Log; 8H?AL
RG
import org.apache.commons.logging.LogFactory; B5G$o{WM
_3a
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/** 3iw9jhK!W
* @author Joa j&.BbcE45
* Oe`t!&v
*/ ^%pwyY\t
publicclass PageUtil { x(=x;X$[^
s`RJl V
privatestaticfinal Log logger = LogFactory.getLog '9@R=#nd
"[yiNJ"kt
(PageUtil.class); vuBA&j0C
T"U t).
/** 8BDL{?Mu
* Use the origin page to create a new page GwBQ
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* @param page |T *qAJ8c
* @param totalRecords R:N-y."La.
* @return n bk(FD6
*/ [[Z>(d$8
publicstatic Page createPage(Page page, int TzGm562o%
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totalRecords){ g/p
}r.
return createPage(page.getEveryPage(), VWt'Kx"
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page.getCurrentPage(), totalRecords); Ah{pidUx
} ,np`:fBMy
;0}2@Q2@ZK
/** mC92J@m/L!
* the basic page utils not including exception PBtU4)
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_
handler \DK*>
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* @param everyPage &,]+>
* @param currentPage D|9fHMg%
* @param totalRecords vWs c{9
* @return page j*d~h$[k
*/ ^~ $&
publicstatic Page createPage(int everyPage, int -FV'%X$i
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currentPage, int totalRecords){ rJp6d :M
everyPage = getEveryPage(everyPage); <|3v@
currentPage = getCurrentPage(currentPage); /g'-*:a
int beginIndex = getBeginIndex(everyPage, <z2mNq
F*VMS
currentPage); vp-7>Wj
int totalPage = getTotalPage(everyPage, y$o=\:
pVS2dwBqE
totalRecords); ^]&{"!
boolean hasNextPage = hasNextPage(currentPage, I?Fa
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totalPage); 5C1Rub)
boolean hasPrePage = hasPrePage(currentPage); K"j=_%{
9dtGqXX
returnnew Page(hasPrePage, hasNextPage, &> .1%x@R
everyPage, totalPage, @;D}=$x
currentPage, :b*`hWnQ
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beginIndex); K/v-P <g
} 1Z8Oh_DC
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privatestaticint getEveryPage(int everyPage){ Ks2%F&\cE
return everyPage == 0 ? 10 : everyPage; UMQW#$~C{g
} 3}{5
X'
I A#*T`
privatestaticint getCurrentPage(int currentPage){ e uHu}
return currentPage == 0 ? 1 : currentPage; O>M*mTM
} R(N(@KC
% W',c u
privatestaticint getBeginIndex(int everyPage, int R+VLoz*J6
\Rqh|T<D
currentPage){ N 3p 7 0
return(currentPage - 1) * everyPage; g*?+~0"`Y
} =GKYroNM
h?3l
privatestaticint getTotalPage(int everyPage, int Ny,A#-?
MI'l4<>u
totalRecords){ W<|K
int totalPage = 0; Bi:wP/>v
3(})uV
if(totalRecords % everyPage == 0) ivz?-X4]
totalPage = totalRecords / everyPage; w<>6>w@GZ
else wU)5Evp[
totalPage = totalRecords / everyPage + 1 ; ]!G>8Rc
<` j[;>O
return totalPage; 2vdQ&H4
} *a,.E6C*
pUMB)(<k
privatestaticboolean hasPrePage(int currentPage){ 3J~kiy.nfW
return currentPage == 1 ? false : true; 3hf;4Mb
} ZHD0u)ri=J
Am%a4{b
privatestaticboolean hasNextPage(int currentPage, U"y'Kd
C1B3VG
int totalPage){ qvU$9cTY
return currentPage == totalPage || totalPage ==
G<-9U}~76
yX.5Y|A<
0 ? false : true; d3=6MX[c
} <ivqe"m
&Dg)"Xji
u4,X.3V]A
} b}&7~4zw
a$zm/
3^R] [;
tZu*Asx7
`I vw`} L
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。 Z++Z@J "
m7wc)"`t
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 ?WQd
'Rkvsch
做法如下: r;on0wm&B
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 CziaxJ
x"llX
的信息,和一个结果集List: g[wP!y%V
java代码: *JY`.t
DPS1GO*
J={OOj
/*Created on 2005-6-13*/ H")N_BB
package com.adt.bo; /=YqjZTCq
yg-FJ/
import java.util.List; MpIw^a3(r
HEB/\
import org.flyware.util.page.Page; mB^I@oZ*
AJ?}Hel[0
/** E/8u'
* @author Joa /x:(SR2,
*/ e8ULf~I
publicclass Result { L>~@9a\jO
4&oXy,8LC
private Page page; n:*_uc^C
vJj:9KcP>h
private List content; by|?g8
9 yW~79n
/** p17|ld`
* The default constructor tf7v5iG e
*/ <5ft6a2fQ
public Result(){ %eJ\d?nw
super(); 3r-Vx P 5n
} }}``~
PJK]t7vp
/** fY%M=,t3c
* The constructor using fields Z.aLk4QO@
* wj#J>C2]
* @param page .YjrV+om1
* @param content qJX+[PJ
*/ B3cf] S%
public Result(Page page, List content){ R?bn,T>
this.page = page; ~X~xE]1o|U
this.content = content; iz9\D*or
} }c35FM,
_z<Y#mik
/** cVB|sYdf
* @return Returns the content. $(KIB82&
*/ ?@lx
publicList getContent(){ M$&WM{Pr^
return content; Q3BLL`W~
} zM_DE
x5fgF;
/** ~tg1N^]kV
* @return Returns the page. rw5#e.~V
*/ JtYYT/PB
public Page getPage(){ 1!>bhH}{D
return page; rq<`(V'2
} /63W\
waXDGdl0
/** cyGN3t9`.
* @param content Tsm1C#6 Y*
* The content to set. JNxW6 cK
*/ 2AXF$YjY
public void setContent(List content){ Th7wP:iDP
this.content = content; ~+pg^en
} H5AK n*'7
Avs7(-L+s
/** 8S.')<-f
* @param page MfXt+c`r
* The page to set. ~A[YnJYA#
*/ 8/Et&TJ`
publicvoid setPage(Page page){ 9Qt)m
fqM
this.page = page; & %N(kyp
} Pn'`Q S?
} vx\nr8'k
y3={NB+
`d}W;&c
I" 8d5a}
6P%<[Z
2. 编写业务逻辑接口,并实现它(UserManager, j<l#qho{h
k
Zk .]b
UserManagerImpl) :S QDqG
java代码: F* 3G_V
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@9_nwf~X4
/*Created on 2005-7-15*/ q4sl=`L5Sp
package com.adt.service; lSn5=^]q
~a'nHy1
import net.sf.hibernate.HibernateException; 3E<aiGU
y\F`B0#$
import org.flyware.util.page.Page; O%YjWb
@DfkGm[%
import com.adt.bo.Result; (@%XWg
"C:rTIH
/** $"Y3mD}?L
* @author Joa \3%W_vU_
*/ +Fk4{p
publicinterface UserManager { C+/Eqq^(
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public Result listUser(Page page)throws a);O3N/*I
#2Ac
HibernateException; H/^~<U#p
_, \y2&KT
} f*{M3"$E
<)_:NRjBF&
X!U]`Qh
6PiEa(
McT\ R{/
java代码: ky'|Wk6
a<f;\$h]
3xBN10R#
/*Created on 2005-7-15*/ 5c<b|
package com.adt.service.impl; MS{Hz,I,
m3U+ du
import java.util.List; ^D9
/
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import net.sf.hibernate.HibernateException; nHI(V-E2:H
`[X6#`<
import org.flyware.util.page.Page; rU;
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import org.flyware.util.page.PageUtil; 8'3"uv
bHO7*E
import com.adt.bo.Result; :0nK`$'
import com.adt.dao.UserDAO; pt=7~+r
import com.adt.exception.ObjectNotFoundException; AiY|O S3R
import com.adt.service.UserManager; *GCA6X
|tG05 +M
/** |2qR^Hd&5
* @author Joa @ L\-ZWq
*/ 5XzrS-I+X@
publicclass UserManagerImpl implements UserManager { C}Rs[
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private UserDAO userDAO; btUq
jVX._bEGX
/** `!zQ
* @param userDAO The userDAO to set. n)tU9@4Np
*/ B:e.gtM5
publicvoid setUserDAO(UserDAO userDAO){ vAi"$e
this.userDAO = userDAO; vz6SCGg,
} JR/W9i
''_,S,.a20
/* (non-Javadoc) 1pWk9Xuh
* @see com.adt.service.UserManager#listUser t G]N*%@
.JNcY]V#
(org.flyware.util.page.Page) 0o;k?4aP.c
*/ ]9fS@SHdx
public Result listUser(Page page)throws <"N:rn{Qq
~q{\;
HibernateException, ObjectNotFoundException { !K!)S^^Po?
int totalRecords = userDAO.getUserCount(); -_s%8l^
if(totalRecords == 0) DD2adu^
throw new ObjectNotFoundException )i&%cyZw
\'[3^/('
("userNotExist"); mRwXN*Izw
page = PageUtil.createPage(page, totalRecords); s jSi;S4
List users = userDAO.getUserByPage(page); GNs#oM
returnnew Result(page, users); -y%QRO(
} \$'R+k-57;
ot^q}fRX
} OSU{8.
V:(y*tFA
jh>N_cp
37#cx)p^f
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 eUYZxe :6
P=2wkzeJj
询,接下来编写UserDAO的代码: P2O\!'aEh
3. UserDAO 和 UserDAOImpl: uG4$2
java代码: O97VdNT8
-4 8`#"xy
KrS
/*Created on 2005-7-15*/ YmOldR9v(
package com.adt.dao; E\ tL
J)_>%.
import java.util.List; 'Cg V0&@
D2{L=
import org.flyware.util.page.Page; 2v4W6R
SBC~QD>L+
import net.sf.hibernate.HibernateException; ?fB5t;~E
K6-6{vt
/** FzVZs#O
* @author Joa lBS"3s384
*/ g#w`J\iz
publicinterface UserDAO extends BaseDAO { 5~QhX22
tbg*_ZQO u
publicList getUserByName(String name)throws 3eWJt\}?B
2H6:np|O
HibernateException; \/n+j!
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publicint getUserCount()throws HibernateException; f#1/}Hq/I
emA.{cVr!
publicList getUserByPage(Page page)throws V- /YNRV
Mw+v"l&mU
HibernateException; _FT6]I0
>d#3|;RY
} I,]J=xi
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a%v>eXc
#vtN+E
java代码: w#sq'vo4%
Vn^)
Zd$JW=KR]l
/*Created on 2005-7-15*/ Z4#v~!
package com.adt.dao.impl; oooS s&t
},&h[\N{6
import java.util.List; Y|_O8[
]Y{,N x
import org.flyware.util.page.Page;
>9{zQf!
pzi q0
import net.sf.hibernate.HibernateException; RB IOdz
import net.sf.hibernate.Query; lirN YJ]tO
G?R_aPP
import com.adt.dao.UserDAO; ,[Ag~.T
1&|
/** P8<hvMF
* @author Joa ~}K{e
*/ f9a$$nb3`
public class UserDAOImpl extends BaseDAOHibernateImpl RtwUb(wn6
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implements UserDAO { "-P/jk
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/* (non-Javadoc) 3-iD.IAUm@
* @see com.adt.dao.UserDAO#getUserByName IytDvz*|
$T?]+2,6;
(java.lang.String) ,m:L2 -J@
*/ Ch t%uzb,
publicList getUserByName(String name)throws b4)k &*dfR
O:._W<
HibernateException { 2$tQ @r
String querySentence = "FROM user in class yyjw?#\8
|kseKZ3
com.adt.po.User WHERE user.name=:name"; @y5= J`@=
Query query = getSession().createQuery 0yaMe@&,
57<Di!rt
(querySentence); x}|+sS,g
query.setParameter("name", name); FfG%C>E6~
return query.list(); V9Hl1\j^
} .;g}%C
Lc%xc`n8B
/* (non-Javadoc) e^8BV;+c
* @see com.adt.dao.UserDAO#getUserCount() y6FKg)
*/ )b9_C
O}
publicint getUserCount()throws HibernateException { r8,om^N6
int count = 0; 4gb'7'
String querySentence = "SELECT count(*) FROM yPN+W8}f
"Vy WT
user in class com.adt.po.User"; l
sr?b
Query query = getSession().createQuery +(&|u q^
T
pD;
(querySentence); *{|$FQnR>(
count = ((Integer)query.iterate().next oqYt/4^Q
`7\H41%\pp
()).intValue(); A?r^V2+j
return count; 'g hys1H
} VX!hv`E
:BD>yOlG
/* (non-Javadoc) s4bv;W
* @see com.adt.dao.UserDAO#getUserByPage 5z Kqb
]Jn2Ra"j
(org.flyware.util.page.Page) QZ~0o7
*/ 03_pwB)^
publicList getUserByPage(Page page)throws mf9hFy*<4
Mg\TH./Y:
HibernateException { 0 sh~I
String querySentence = "FROM user in class MMd.0JuaO
#ouE r-=
com.adt.po.User"; n}OU Y
Query query = getSession().createQuery ?-,6<K1
j^ nu|
(querySentence); \c%g M1
query.setFirstResult(page.getBeginIndex()) 9@'4P
.setMaxResults(page.getEveryPage()); $@.jZ_G
return query.list(); i?-Y
} =?/&u<
ISBF\ wQY
} (:7a&2/M
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S3y246|4
]2$x|#Gg}
>
c:Zx!
至此,一个完整的分页程序完成。前台的只需要调用 #c:kCZt#
E-SG8U;
userManager.listUser(page)即可得到一个Page对象和结果集对象 `tVy_/3(9
b 4OnZ;FI
的综合体,而传入的参数page对象则可以由前台传入,如果用 ^{[[Z.&R?
,hvc``j
S8
webwork,甚至可以直接在配置文件中指定。 |r !G,
,Xtj;@~-
下面给出一个webwork调用示例: KUKI qAA
java代码: bo>E"<
8R?I`M_b
c1#+Vse
/*Created on 2005-6-17*/ GHG,!C
package com.adt.action.user; 6|#g+&[
2*'ciH37
import java.util.List; ]0-<>
4Jykos2
import org.apache.commons.logging.Log; QN g\4%
import org.apache.commons.logging.LogFactory;
KGT3|)QN
import org.flyware.util.page.Page; x<F$aXOS
iRve)
import com.adt.bo.Result; K<RqBecB
import com.adt.service.UserService; x0<^<D &Q
import com.opensymphony.xwork.Action; 0T9.M(
"
"%#cDR
/** LGVlc@0'
* @author Joa 1-o V-K
*/ `D2Mss$!
publicclass ListUser implementsAction{ ArXl=s';s4
t9` Ed>a
privatestaticfinal Log logger = LogFactory.getLog Ct!S Tk[2
>lLo4M 3
(ListUser.class); vD26;S.y[a
X"<|Z]w
private UserService userService; {[^#h|U
Ep ">v>"
private Page page; bV6V02RF
{7X~!e|w
privateList users; a+
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doLNz4W
/* wW5Yw
i
* (non-Javadoc) E9$H nj+m
* B*79qq
* @see com.opensymphony.xwork.Action#execute() C6^j#rl
*/ 5[R?iSGL1
publicString execute()throwsException{ MLS;SCl
Result result = userService.listUser(page); u)~s4tP4
page = result.getPage(); ab4LTF|
users = result.getContent(); !y*oF{RZ
return SUCCESS; 6fGK(r
} .NnGVxc5*
1;&T^Gdj
/** tX?J@+
* @return Returns the page. e U;jP]FA
*/ XwPx9+b6j
public Page getPage(){ hY=I5[*
return page; (>AFyh&3,X
} P%)b+H{$h
sfI N)jh
/** BX3lPv
* @return Returns the users. i0ybJOa4
*/ LNiS`o\
publicList getUsers(){ a.,_4;'UE1
return users; +)gB9DoK
} O-!,Jm
`{}@@]
/** &J(!8y*QyE
* @param page @O/,a7Tt
* The page to set. T|bZ9_?+2
*/ \_U*t!
publicvoid setPage(Page page){ &t_h'JX&
this.page = page; <[hz?:G"$
} o^GC=Aca`
1JeJxzv>C
/** PAoX$q
* @param users # ZTLrq5b
* The users to set. <'2u
a
*/ [@2s&Ct;
publicvoid setUsers(List users){ %h/! Y<%
this.users = users; MGybGbd
} @a(oB.i
784;]wdy\
/** RGp'b
* @param userService 2 ~-( A
* The userService to set. ikHOqJ-,m
*/ p(?3
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publicvoid setUserService(UserService userService){ m&Sp1=*Ejy
this.userService = userService; @q)E=G1<o0
} JIV8q HC
} XKSX#cia
q%S8\bt
xR}of"
K)5;2lN,
fl)zQcA
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, d?7BxYaa
V(..8}LlD
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 (}~ucI<~
x6e +7"#~
么只需要: %U?)?iZdL
java代码: 7\%$>< K
]o*$h$? s
) 4ncutb
<?xml version="1.0"?> O<X
)p`,`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 38wq (
5i9Ub|!P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w-FHhf
]^'ZiyJX
1.0.dtd"> Q52bh'cuU
C #aFc01B
<xwork> SRWg[H
-*3(a E
<package name="user" extends="webwork- or.\)(m#(
B_&^ER5j
interceptors"> 5^2TfG9
bQ.nFa']
<!-- The default interceptor stack name CQ1 8%w6
Ja [#[BJ?
--> X6kaL3L}
<default-interceptor-ref |Puj7Ru
u+z~
name="myDefaultWebStack"/> =|V"#3$f
e &Rb
<action name="listUser" vgAFuQi(
5/(sjMB
class="com.adt.action.user.ListUser"> a_%>CD${t
<param Q>%E`h
Yxqj -
name="page.everyPage">10</param> !I7 ?
<result %zflx~
OG}KqG!n
name="success">/user/user_list.jsp</result> ?O7iK<5N
</action> @_Sp3nWdu
^ZVOql&
</package> ~`[8"YUL
Zs73
ad
</xwork> 8A4TAT4,
3#mE(
`|P
[gn[nP9
XtzOFx/
{u4i*udG`)
`^%@b SE(
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 Tk](eQsy.v
PUKVn+h
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。 d?}hCo=/Xq
#ovM(Mld
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 vX.]hp5~
A^L?_\e6
e^WqJ7j
5L3{w+V
' &N20w
我写的一个用于分页的类,用了泛型了,hoho cNeiD@t3V&
KBj@V6Q
java代码: ~'{VaYk]v
SwJHgZ&
,!H\^Vfl
package com.intokr.util; #[(gIOrNn8
D-D# `
import java.util.List; I4:rie\hjC
_.-#E$6s#q
/** N'a?wBBR
* 用于分页的类<br> tvCcyD%w
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -R8/`M8GbD
* g-|Kyhr?=
* @version 0.01 y9ip[Xn-$:
* @author cheng =h7[E./U1
*/ "$P'Wv
public class Paginator<E> { P
eHW[\)
privateint count = 0; // 总记录数 QH:>jmC{1h
privateint p = 1; // 页编号 W1`Dx(g
privateint num = 20; // 每页的记录数 B'#4;R!8P=
privateList<E> results = null; // 结果 iLQSa7
)*W=GY*
/** RUqO!s~#rY
* 结果总数 KG-y)qXu
*/ ph+M3q(z
publicint getCount(){ h,~tXj
return count; $$\V2%v
} ^vG=|X|)c
X&.:H~xS+
publicvoid setCount(int count){ Nuo^+z
E
this.count = count; WV@X@]U
} Qxky^:B
e`;t<7*i
/** hd8B0eD'
* 本结果所在的页码,从1开始 y,V6h*x2
* "R8.P/ 3
* @return Returns the pageNo.
}Zt.*%
*/ R)Q/Ff@o0
publicint getP(){ l[Tt[n
return p; @wMQC\Z
} |SxMN%M!
%fBP:5%K
/** 4?v$<=#21*
* if(p<=0) p=1 r:73uRk
* 3Qk/ Ll
* @param p nPcxknl(pd
*/ a^(2q{*
publicvoid setP(int p){ n
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if(p <= 0) {N"*olx
p = 1; 7MoR9,(
this.p = p; z>7=k`x`:
} }'v{dK
%uj[ `
/** .(JE-upJ"
* 每页记录数量 hRa\1Jt>a
*/ *^uGvJXF
publicint getNum(){ p1kl LX
return num; ^] i"
H|(x
} ?P%|P
%n4@[fG%K
/** &{BBxv)y
* if(num<1) num=1 ?THa5%8f
*/ J}:&eS
publicvoid setNum(int num){ ed=n``P~}
if(num < 1) IeH^Wm&^
num = 1; `|&\e_"DE
this.num = num; s:3aRQ%
} J0Jr
BXCh
k&yQ98H$K"
/** UmYD]
* 获得总页数 1E8$% 6VV
*/ /9P^{OZ;y
publicint getPageNum(){ (VfwLo>#
return(count - 1) / num + 1; 6={IMkmA
} RXUA!=e
7,f:Qi@g
/** Ndo}Tk!
* 获得本页的开始编号,为 (p-1)*num+1 J_|7$
l/
*/ 4C6=77Jr
publicint getStart(){ =Y/}b\9`T
return(p - 1) * num + 1; q)NXyy4BT
} DQ%`v=
E1#H{)G
/** K4_~ruhr
* @return Returns the results. N`f!D>b:dn
*/ Rq"VB.ef&{
publicList<E> getResults(){ dJloH)uJZ>
return results; Ih(:HFRMq6
} $|rCrak;
={\![{L
public void setResults(List<E> results){ DE5d]3B
this.results = results; z'?SRK5+
} I; ^xAd3G
?Y%}(3y
public String toString(){ @ <|6{N<
StringBuilder buff = new StringBuilder sf
fV.cC`
"v@);\-V
(); 6euR'd^Qi
buff.append("{"); 1]"D%U=
buff.append("count:").append(count); 2@rp<&s
buff.append(",p:").append(p); WfRVv3Vm
buff.append(",nump:").append(num); jMTRcj];(
buff.append(",results:").append W&HF?w}s
uPI v/&HA
(results); K/!/M%GB6
buff.append("}"); ur?d6a
return buff.toString(); v hRu`Yb
} -)p@BtMS
>Dk1axZ!>/
} Tnf&pu#5
)ZQHa7V
2r
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