Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <.(IJ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T+NEw8C?/
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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 /S1EQ%_
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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 mbv\Gn#>
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分页支持类: is?`tre\P
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java代码: jV8mn{<
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package com.javaeye.common.util; '|&}rLr:+
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import java.util.List; 3 8pw
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publicclass PaginationSupport { sp0&"&5
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publicfinalstaticint PAGESIZE = 30; @!fy24R]D
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privateint pageSize = PAGESIZE; LgRx\*[C*
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privateList items; :Gqyj_|<
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privateint totalCount;
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privateint[] indexes = newint[0]; 1QtT*{zm$F
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privateint startIndex = 0; pA3j@w
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public PaginationSupport(List items, int U`K5 DZ~
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totalCount){ R"e~0WO
setPageSize(PAGESIZE); 'IP'g,o++
setTotalCount(totalCount); )52:@=h*l
setItems(items); n9gj{]%
setStartIndex(0); cKh { s
} pD##lkJr
iHr{
VQ
public PaginationSupport(List items, int (S0MqX*
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totalCount, int startIndex){ c.m '%4
setPageSize(PAGESIZE); f"xi7vJv!f
setTotalCount(totalCount); K8Gc5#OF
setItems(items); T({:Y. A;
setStartIndex(startIndex); bM_Y(TgJ
} _ot4HmD
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public PaginationSupport(List items, int Xw`vf7z*
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totalCount, int pageSize, int startIndex){ mj[PKEdkB
setPageSize(pageSize); !1C3{
setTotalCount(totalCount); r^ S4 I&
setItems(items); JTNQz
setStartIndex(startIndex); uTA
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} }D xXt
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publicList getItems(){ uT8/xNB!
return items; Vk y~yTL)\
} rK)So#'
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publicvoid setItems(List items){ qC SJ=T;
this.items = items; />Tyiy]2uu
} ?}m/Q"!1
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publicint getPageSize(){ 7S7gU\qOj
return pageSize; UAnq|NJO
} bWt>tEnf
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publicvoid setPageSize(int pageSize){ .UakO,"z
this.pageSize = pageSize; )W:`Q&/G
} A@j;H|
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publicint getTotalCount(){ l2+qP{_4
return totalCount; :t?9$ dL
} mwZesSxB_
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publicvoid setTotalCount(int totalCount){ eU1= :n&&\
if(totalCount > 0){ 1B+MCt4
this.totalCount = totalCount; r*N:-I~z
int count = totalCount / 1HskY| X
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pageSize; '(5 &Sj/C
if(totalCount % pageSize > 0) v/c8P\
count++; :J@q
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indexes = newint[count]; +&jWM-T"-
for(int i = 0; i < count; i++){ 2"~!Pu^.j
indexes = pageSize * pL]C]HGv
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i; 0J_ AX
} ?O8NyCeb7
}else{ n <6}
this.totalCount = 0; w
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} KM g`O3_16
} Nm--h$G
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publicint[] getIndexes(){ c ^G\w+_
return indexes; Vl{CD>$,
} x1Q}B
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publicvoid setIndexes(int[] indexes){ ?cG+rC%
this.indexes = indexes; YPDc
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} }9R45h}{<
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publicint getStartIndex(){ Ms<^_\iPN
return startIndex; l,1 }1{k&
} x +!<_p
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publicvoid setStartIndex(int startIndex){ >@[`,
if(totalCount <= 0) @es}bKP
this.startIndex = 0; ?;0=>3p*0
elseif(startIndex >= totalCount) u'd+:uH
this.startIndex = indexes q#pBlJ.LK
q =b.!AZy
[indexes.length - 1]; U;?%rM6
elseif(startIndex < 0) i92{N$*x
this.startIndex = 0; 0Tp?ED_
else{ ~2
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this.startIndex = indexes qRJg/~_h{
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[startIndex / pageSize];
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} f?dNTfQ3mi
} F4k<YU
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publicint getNextIndex(){ Y6`9:97
int nextIndex = getStartIndex() + X;w1@4!
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pageSize;
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if(nextIndex >= totalCount) :t(gD8 ;
return getStartIndex(); K-)*S\<}
else b5_A*-s$M
return nextIndex; [])M2_
} la8se=^
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publicint getPreviousIndex(){ [NFg9y;{h
int previousIndex = getStartIndex() - H'<9;bD -
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pageSize; +IuV8XT2(
if(previousIndex < 0) vROl}s;
return0; DOkEWqM!
else 2
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return previousIndex; ?p. dc~tZ
} vPi\ vU{
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} G 8uX[-L1
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抽象业务类 j~\\,fl=
java代码: mZ/?uPIa
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/** #Jy+:|jJ
* Created on 2005-7-12 IQGIU3O
*/ [^"e~
package com.javaeye.common.business; izY,t!
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import java.io.Serializable; 3Nr8H.u&q
import java.util.List; kC01s
3 V8SKBS
import org.hibernate.Criteria; L^RyJ;^c
import org.hibernate.HibernateException; &'WgBjP
import org.hibernate.Session; PaMi5Pq
import org.hibernate.criterion.DetachedCriteria; y3 LWh}~E
import org.hibernate.criterion.Projections; ) OZDq]mV
import 5iG|C ~
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org.springframework.orm.hibernate3.HibernateCallback; BR*""/3`
import @`%.\_
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org.springframework.orm.hibernate3.support.HibernateDaoS 5c{=/}Y
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upport; xdYjl.f
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import com.javaeye.common.util.PaginationSupport; RZOk.~[v
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public abstract class AbstractManager extends -|J?-
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HibernateDaoSupport { rQKBT]?y
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privateboolean cacheQueries = false; -7=pb#y
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privateString queryCacheRegion; dr'6N1B@
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publicvoid setCacheQueries(boolean lD/+LyTa
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cacheQueries){ I62Yg
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this.cacheQueries = cacheQueries; .~b6wi&n
} >z[d~
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publicvoid setQueryCacheRegion(String ?W.Y
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queryCacheRegion){ _r^&.'q
this.queryCacheRegion = fC~WuG3
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queryCacheRegion; YRC`2)_'
} ?hfosBn&[
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publicvoid save(finalObject entity){ 'JkK0a2D
getHibernateTemplate().save(entity); veK
} U(J?Q
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publicvoid persist(finalObject entity){ WZFV8'
getHibernateTemplate().save(entity); )'fIrBT
} sjaG%f&h
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publicvoid update(finalObject entity){ !w
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getHibernateTemplate().update(entity); `bH Eu"(,
} Crww\#E;
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publicvoid delete(finalObject entity){ q=[0`--cd
getHibernateTemplate().delete(entity); >!a*wf~]
} 2V~Yb1P
sZB$+~.:}
publicObject load(finalClass entity, sq<y2j1oF
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finalSerializable id){ 9$)4C|
return getHibernateTemplate().load A#8/:t1AW
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(entity, id); ,u\M7,a^
} K-#Rm%J+Wy
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publicObject get(finalClass entity, RrRCT.+E
!{ )H
finalSerializable id){ u}ab[$Q5
return getHibernateTemplate().get gbSZ-
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(entity, id); T>1E
} !5{t1 oJ
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publicList findAll(finalClass entity){ .m+KXlP
return getHibernateTemplate().find("from 8{h:z
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" + entity.getName()); ? 8'4~1g`}
} AQ-PY
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publicList findByNamedQuery(finalString Uz
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namedQuery){ O%VA)<
return getHibernateTemplate _4!{IdR
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().findByNamedQuery(namedQuery); 1vsu[n
} V4EM5 Z\k
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publicList findByNamedQuery(finalString query, &N9IcNP
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finalObject parameter){ /yp/9r@T0
return getHibernateTemplate v~aLTI
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().findByNamedQuery(query, parameter); |=u96G~N
} W]@6=OpH
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publicList findByNamedQuery(finalString query, Ysl9f1>%
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finalObject[] parameters){ q-H&5K
return getHibernateTemplate yYk|YX(7U
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().findByNamedQuery(query, parameters); jOv~!7T
} [n!x&f8Xh
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publicList find(finalString query){ N|$5/bV
return getHibernateTemplate().find 19) !$Hl
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(query); ZHcONYAr
} mV%h[~-
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publicList find(finalString query, finalObject @C07k^j=U
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parameter){ Gn[ *?=Vy
return getHibernateTemplate().find $Ba`VGP>)3
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(query, parameter); lU&Q^Zj`
} );!dg\U
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public PaginationSupport findPageByCriteria ?l>e75V%w
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q
(final DetachedCriteria detachedCriteria){ .c03}RTC^
return findPageByCriteria '(XW$D
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(detachedCriteria, PaginationSupport.PAGESIZE, 0);
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} UFL0 K
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public PaginationSupport findPageByCriteria C-r."L
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(final DetachedCriteria detachedCriteria, finalint [{?;c+[
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startIndex){ 4sI3(z)9H
return findPageByCriteria @|Z*f\
(5>{?dR)|
(detachedCriteria, PaginationSupport.PAGESIZE, 7f[8ED[4
tjt=N\;
startIndex); -}NAb^d
} xTGP
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public PaginationSupport findPageByCriteria $,g 3*A
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(final DetachedCriteria detachedCriteria, finalint ~T;K-9R
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pageSize, 0@:Y>qVa
finalint startIndex){ G[vUOEU~O
return(PaginationSupport) \l>qY(gu
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getHibernateTemplate().execute(new HibernateCallback(){ -aC!0O y`
publicObject doInHibernate ^Kb9@lz/
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(Session session)throws HibernateException { EUJ1RhajF
Criteria criteria = _, 11EeW@
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detachedCriteria.getExecutableCriteria(session); u=1B^V,6V
int totalCount = :v|r= #OI
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((Integer) criteria.setProjection(Projections.rowCount []^PJ
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()).uniqueResult()).intValue(); c1 gz#,
criteria.setProjection TJeou#=/
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(null); _G_ &Me0
List items = Z $ p^v*y
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criteria.setFirstResult(startIndex).setMaxResults `;zu1o
i=,B88ko
(pageSize).list(); bjU 2UcI"<
PaginationSupport ps = e);bF>.~
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new PaginationSupport(items, totalCount, pageSize,
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startIndex); ~gSF@tz@
return ps; WO.}DUfG+
} t;Fbt("]:
}, true); KIXwx98
} 6,CU)-98G
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public List findAllByCriteria(final f\U? :83
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DetachedCriteria detachedCriteria){ l5":[C$
return(List) getHibernateTemplate zsR wF
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().execute(new HibernateCallback(){ B}l}Aq8
publicObject doInHibernate gxBl1
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(Session session)throws HibernateException { a PcGI
Criteria criteria = q?e16M
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detachedCriteria.getExecutableCriteria(session); l^!0|/Vw
return criteria.list(); A?6{
} 4iL.4Uj{N
}, true); %^Q@*+{:f
} 5JXzfc9rL
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public int getCountByCriteria(final 3 cV+A]i
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DetachedCriteria detachedCriteria){ : .FfE
Integer count = (Integer) &VZmP5Gv
)Rm
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getHibernateTemplate().execute(new HibernateCallback(){ #%}u8\q
publicObject doInHibernate IV
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(Session session)throws HibernateException { Qzs\|KS
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); +r#=n7t
return >? A `C!i
dwf #~7h_
criteria.setProjection(Projections.rowCount 8h@)9Q]d\
cfy/*|
()).uniqueResult(); {C,1w
} hVt+%tmNy
}, true); R"\ub"]
return count.intValue(); !lt\2Ae
} .9[8H:Fe
} oE|u;o
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用户在web层构造查询条件detachedCriteria,和可选的 >w]k3MC
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 '@}?NV0
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PaginationSupport的实例ps。 Ymk4Cu.s
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ps.getItems()得到已分页好的结果集 G~iYF(:&
ps.getIndexes()得到分页索引的数组 2'UFHiK
ps.getTotalCount()得到总结果数 }T1Xds8w)t
ps.getStartIndex()当前分页索引 #&`WMLl+8
ps.getNextIndex()下一页索引 V~uA(3\U
ps.getPreviousIndex()上一页索引 ;P0Y6v3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C[<\ufclD
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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 YI\Cs=T/
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一下代码重构了。 YQ8x6AJ
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我把原本我的做法也提供出来供大家讨论吧: 'N5r2JL[w
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首先,为了实现分页查询,我封装了一个Page类: F>_lp,G
java代码: 6x3Ew2
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/*Created on 2005-4-14*/ <~8f0+"
package org.flyware.util.page; CbvL X="%
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/** +so o2cb
* @author Joa Y(!)G!CMc
* 9(evHR7
*/ *[5#g3
publicclass Page { cZK?kz_Y
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/** imply if the page has previous page */ "BNmpP
privateboolean hasPrePage; xXh]z|
*CD=cmdD*
/** imply if the page has next page */ g8*|"{
privateboolean hasNextPage; o!dkS/u-m
C5z
/** the number of every page */ ]8cX#N,M
privateint everyPage; ^@w1Z{:
cFNtY~(b
/** the total page number */ XV9'[V
privateint totalPage; T-cVM>u\D
c+M@{EbuN
/** the number of current page */ e&7}N Za
privateint currentPage; =,;3z/k%
kK6>>lD'
/** the begin index of the records by the current (%IstR|u:
=]k_Oq-1h
query */ 'eXw`kw(
privateint beginIndex; lz5j~t5>Q
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/** The default constructor */ rca"q[,
public Page(){ +|w~j#j9`
v%e"4:K}?
} 39m"}26*E
!8M'ms>s=
/** construct the page by everyPage }XE/5S}D
* @param everyPage o)
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* */ v2z/|sG
public Page(int everyPage){ TZ]Gl4@
this.everyPage = everyPage; @G{DOxE*
} 6$;)CO!h
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/** The whole constructor */ +FK<j;}C7
public Page(boolean hasPrePage, boolean hasNextPage, }Q(I&uz
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VDN]P3
int everyPage, int totalPage, !{0!G
int currentPage, int beginIndex){ O|m-k0n
this.hasPrePage = hasPrePage; _$lQK{@rY
this.hasNextPage = hasNextPage; W5;sps
this.everyPage = everyPage; {vlh,0~
this.totalPage = totalPage; >k-poBw
this.currentPage = currentPage; !XC7FUO
this.beginIndex = beginIndex; A84HaRlkF5
} d)sl)qt}0
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/** fs12<~+z
* @return " <AljgF
* Returns the beginIndex. m"}G-#
*/ /LzNr0>2
publicint getBeginIndex(){ ".Ug
A\0
return beginIndex; Or|LyQU
} L
*@>/N
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/** "j>0A
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* @param beginIndex t,6=EK*3T
* The beginIndex to set. 1OL~)X3
*/ \ed(<e>
publicvoid setBeginIndex(int beginIndex){ RwKN
this.beginIndex = beginIndex; ZQ/5]]}3y
} P.7B]&T6
uuB\~ #?T
/** ;0E4S
* @return K-5)Y+| >
* Returns the currentPage. p(>'4#|qy
*/ "bH ~CG:Y
publicint getCurrentPage(){ ^Pwq`G A
return currentPage; q[ZYlF,Ho
} hSH-Ck@Qy
Y$^QH.h
/** f*Bc`+G
* @param currentPage ]CYe=m1<2Q
* The currentPage to set. yfrgYA
*/ )M~5F,)
publicvoid setCurrentPage(int currentPage){ J)]W[Nk
this.currentPage = currentPage; kOO2 ?L|Z
} jF8ld5|_|
#'P&L>6
;
/** x1h!_^(QfF
* @return #oI`j
q
* Returns the everyPage. XRkqMq%
*/ %LyB~X
publicint getEveryPage(){ Tj:F Qnx
return everyPage; 9Wn0YIc
} pppbn]%Ob
KtE`L4tW6
/** AXFVsZH"zi
* @param everyPage {Bx\Z0+'&
* The everyPage to set. )U`
c9*.
*/ zFIbCv8
publicvoid setEveryPage(int everyPage){ | Z;Av%%
this.everyPage = everyPage; -_+0[Nb.
} % |V:F. f
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/** Rk<:m+V=
* @return
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* Returns the hasNextPage. _C?K;-v}
*/ NNX/2
publicboolean getHasNextPage(){ qyto`n7
return hasNextPage; W7 $yE},z
} KH-.Z0
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H
/** O7W}Z1G
* @param hasNextPage i~4Kek6,I
* The hasNextPage to set. @gd-lcMYW
*/ 8}&cE#@
publicvoid setHasNextPage(boolean hasNextPage){ Rp#SqRy`
this.hasNextPage = hasNextPage; Tn|reXc0e
} -Ac^#/[0
tB[K4GNSQ
/** *T3"U|0_ y
* @return T!n<ya!
* Returns the hasPrePage. I('l)^m%
*/ 8^T' a^Wt
publicboolean getHasPrePage(){ E_?
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return hasPrePage; DE[y&]/C{
} |Z<adOg
&8N\
6K=
/** {VFpfo
* @param hasPrePage ,xiRP$hGhh
* The hasPrePage to set. WJ%b9{<
*/ 3jQ
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publicvoid setHasPrePage(boolean hasPrePage){ )S]c'}^
this.hasPrePage = hasPrePage; V1+IqOXAIp
} |D\ ukml
*ULXJZ%
/** ',.Xn`c
* @return Returns the totalPage. ]2<g"zo0
* yfU1;MI
*/ TZ/u"' ZS
publicint getTotalPage(){ a P`;Nr=
return totalPage; _*+M'3&=
} hk~s1"
hAY_dM
/** SXhJz=h
* @param totalPage (Fu9lW}n
* The totalPage to set. i}Y:o}
*/ 9O|m#&wa]
publicvoid setTotalPage(int totalPage){ n4ISHxM
this.totalPage = totalPage; F/&&VSv>LO
} KMZ% 1=a
y==x
} Q>|<R[.7
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,Rf<6 /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 6(eyUgnb
#e=[W))
个PageUtil,负责对Page对象进行构造: ZqSczS7uf
java代码: 7,:QFV
lwV#j}G
I!{5*~ 3
/*Created on 2005-4-14*/ 5y.kOe4vH
package org.flyware.util.page; V%"aU}
1v`*%95
import org.apache.commons.logging.Log; 3t8VH`!mL{
import org.apache.commons.logging.LogFactory; q$\KE4v"
1Ztoj}!I
/** /:B!hvpw
* @author Joa %kF6y_h`
* Z5v\[i@H!
*/ o_{-X 1w
publicclass PageUtil { 7%C6gU!r
zh7NXTzyf
privatestaticfinal Log logger = LogFactory.getLog T$SGf.-
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(PageUtil.class); V4_ZBeWA
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/** +dlN^P647
* Use the origin page to create a new page |SCO9,Fs
* @param page QO~!S_FRH
* @param totalRecords L_Z>*s&
* @return \:8
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*/ )A,MTi
publicstatic Page createPage(Page page, int T$!.
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(r.[b
totalRecords){ ?m0|>[j
return createPage(page.getEveryPage(), NU O9,
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page.getCurrentPage(), totalRecords); ',~,hJ0
} `i;f
,-D3tleu`
/** *{6{ZKM
* the basic page utils not including exception q9|'!m5K
lx(kbSxF
handler ("?V|
* @param everyPage O(#DaFJv
* @param currentPage (}
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* @param totalRecords 4YMX;W
* @return page E{*d`n
*/ DJR_"8
publicstatic Page createPage(int everyPage, int az/NZlJhT
$cflF@3
currentPage, int totalRecords){ _e:c
22T'
everyPage = getEveryPage(everyPage); z&Cz!HrS
currentPage = getCurrentPage(currentPage); P 9c!
int beginIndex = getBeginIndex(everyPage, '>4H#tu
o !bV;]
currentPage); ;<hLy(@
int totalPage = getTotalPage(everyPage, sN"<baZ
5o2w)<d!
totalRecords); @~sJ
((G[5
boolean hasNextPage = hasNextPage(currentPage, '*lVVeSiFw
~Z-o2+xA
totalPage); O%}?DiSl
boolean hasPrePage = hasPrePage(currentPage); m9M#)<@*
RzhAXI=
returnnew Page(hasPrePage, hasNextPage, 4j_\_:$w<
everyPage, totalPage, t\S=u y
currentPage, UB^OMB-W.m
6
);8z!+
beginIndex); RqB 8g
} "lLwgh;
n)wpxR
privatestaticint getEveryPage(int everyPage){ }ii]cY
return everyPage == 0 ? 10 : everyPage; ~;O=
7
} 4o)\DB?!
?[L0LL?ce
privatestaticint getCurrentPage(int currentPage){ AIRVvW~($
return currentPage == 0 ? 1 : currentPage; -c<1H)W
} 61eKGcjs:
9{]r+z:
privatestaticint getBeginIndex(int everyPage, int NGb!7Mu9
f'zFg["aZS
currentPage){ _>:=<xyOq
return(currentPage - 1) * everyPage; @u'27c_<d3
} 2dV\=vd
\ /X!tlwxh
privatestaticint getTotalPage(int everyPage, int zf!\wY"`
3K'o&>}L
totalRecords){ hz~CW-47
int totalPage = 0; %&Q7;?
PB3!;
if(totalRecords % everyPage == 0) <K.C?M(9
totalPage = totalRecords / everyPage; smLDm
else oe_[h]Hgl
totalPage = totalRecords / everyPage + 1 ; /o06h y
$nd-[xV
return totalPage; *mhw5Z=!
} WUOPYYW<o
u>i+R"hi"
privatestaticboolean hasPrePage(int currentPage){ J/&*OC
return currentPage == 1 ? false : true; uL2{v
} Z?!:=x>7m
BO\`m%8md
privatestaticboolean hasNextPage(int currentPage, s"Pk-Dv
*$Wx*Jo
int totalPage){ +q,n}@y=
return currentPage == totalPage || totalPage == M0IqQM57N
9oau_Q#
0 ? false : true; +nyN+X34B
} )+{omQ7v
KL\=:iWA
L"vG:Mq@D
} kE(-vE9
rpP+20 v
1X_!%Z
O}iKPY8K
2d J)4
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。 cM'[;u
8{=(#]
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 \U =>
%|6Q7'@p
做法如下: y42T.oK8c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 hD.wKX?oO
!";$Zu
的信息,和一个结果集List: Kz2^f@5=F
java代码: yW,#&>]# |
O
NzdCgY
6!PX!
UkF
/*Created on 2005-6-13*/ ~ilBw:L-3
package com.adt.bo; `,]PM)iC
0+`*8G)
import java.util.List; Jt^JE{m9%
k.f:nv5JO
import org.flyware.util.page.Page; Ox1QP2t6Y
&XTd[_VW!
/** @9P9U`ZP
* @author Joa -r0\
*/ ;xC~{O
publicclass Result { JWjp<{Q;1
&zDFf9w2{
private Page page; ba:^zO^
&y wY?ox
private List content; `D4'`Or-U
yFtf~8s3
/** rSCX$ @@F
* The default constructor :rc[j@|pH
*/ AS^$1i:
public Result(){ WC; a
super(); 3sIM7WD?
} i_^NbC
^moIMFl
/** 5!fW&OiY
* The constructor using fields q)y8Bv|
* Pu*UZcXY
* @param page eV}Tx;1|}
* @param content 4?uG> ;V
*/ RIx6& 7$
public Result(Page page, List content){ %+J*oFwQu
this.page = page; Y}z?I%zL
this.content = content; HaUo+,=
} zhL,BTH
bncFrzp#o
/** 4u7>NQUDu
* @return Returns the content. .?]_yX
*/ eR;0pWVl
publicList getContent(){ zwK;6&(W
return content; 2 -8:qmP(
} 'mR+W{r
W4Q]<<6&
/** z9w.=[Io
* @return Returns the page.
>ON.ftZi
*/ %W@IB8]Vr
public Page getPage(){ 8"^TWzg}L
return page; uS,$P34^oy
} T+!kRigN~P
i|'t!3I^m
/** =1Jo-!{{
* @param content ;wB3H
* The content to set. !-~(*tn
*/ G"wQ(6J@
public void setContent(List content){ ywte\}
this.content = content; DJUtuex
} ~Wv?p4
yK3z3"1M?
/** &i RX-)^u
* @param page NE"fyX`
* The page to set. #1R
%7*$i
*/ L\DaZ(Y
publicvoid setPage(Page page){ 2_v>8B
this.page = page; "
z{w^k
} k=_@1b-
} {Wo7=aR
miqCUbcU
eRbO Hj1
p7er04/}\
"-%H</
2. 编写业务逻辑接口,并实现它(UserManager, ~yN,F pD
U)8]pUI+/P
UserManagerImpl) 2O/_hv.
java代码: |e>-v
*Cw2 h
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/*Created on 2005-7-15*/
jfamuu 7
package com.adt.service; XT"c7]X
*_wBV
M=2
import net.sf.hibernate.HibernateException; wP*Z/}Uum+
H;1}Nvvd
import org.flyware.util.page.Page; *2F}e4v
IIkJ"Qg.
import com.adt.bo.Result; 4^&vRD,
UEUTu}4y
/** X $f%Ss
* @author Joa 605|*(
*/ ':3KZ4/C
publicinterface UserManager { HenJlo
\ 714 Pyy
public Result listUser(Page page)throws LNkyV*TI
xTT>3Fj
HibernateException; #ZA
YP
P>|2~YxjU
} v&n&i?
j$6}r
1oPT8)[U
)Yml'?V"
uc_
X;M;
java代码: q@:&^CS
I?QKd@
@zbXG_J
/*Created on 2005-7-15*/ OjZ@_V:
package com.adt.service.impl; g5)VV"
;/@R{G{+~;
import java.util.List; |Bp?"8%*l
hlRE\YO&8R
import net.sf.hibernate.HibernateException; T (qu~}
!r<7]nwV
import org.flyware.util.page.Page; |{
kB`
import org.flyware.util.page.PageUtil; Ty=}A MMyE
K_i2%t3
import com.adt.bo.Result; Qxwe,:
import com.adt.dao.UserDAO; |($pXVLH`
import com.adt.exception.ObjectNotFoundException; )-(NL!?`
import com.adt.service.UserManager; o#i{/#oF
Gsb]e
/** KjadX&JD
* @author Joa ze-iDd_y
*/ GOt@x9%
publicclass UserManagerImpl implements UserManager { pfT7
?U |lZ~o
private UserDAO userDAO; 3r\QLIr L8
b}fH$.V@
/** .qZ<ROZ
* @param userDAO The userDAO to set. .eE5pyw+C
*/ <6@Db$-
publicvoid setUserDAO(UserDAO userDAO){ 4T:ZEvdzf
this.userDAO = userDAO; M-NR!? 9
} J8jbtL O'
O%Mh
g\#B
/* (non-Javadoc) WI%,m~
* @see com.adt.service.UserManager#listUser wNlp4Z'[
Fq8Z:;C8
(org.flyware.util.page.Page) C
RNO4
*/ 9:1ZL_yf
public Result listUser(Page page)throws q
bo`E!K
W+QI
D/
HibernateException, ObjectNotFoundException { ?1YK-T@
int totalRecords = userDAO.getUserCount(); N67m=wRx
if(totalRecords == 0) 1peN@Yk2W
throw new ObjectNotFoundException QZX+E
y=t
-/*K
("userNotExist"); Cd4G&(=
page = PageUtil.createPage(page, totalRecords); =_5-z|<
List users = userDAO.getUserByPage(page); J&Ah52
returnnew Result(page, users); Qi9SN00F.
} o.,hCg)X
qg_=5s
} m9r
X
*p"%cas
~!I
\{(
Yv>% 5`
3o h(d.Z
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 dI`b AP;\
#<{sP0v*
询,接下来编写UserDAO的代码: \Q]7Hw<
3. UserDAO 和 UserDAOImpl: G=DRz F
java代码: SJ<nAX
Kg56.$
./u3z|q1
/*Created on 2005-7-15*/ ]'hz+V31%
package com.adt.dao; yovC~
e7-U0rrE
import java.util.List; )<%GHDWL
U<zOR=_
import org.flyware.util.page.Page; 06ZyR@.@v
X4gs{kx}|
import net.sf.hibernate.HibernateException; Z<`QDBN"4
^]K_k7`I
/** MFRM M%`
* @author Joa 3>ytpXUEGx
*/ 3:s!0ty"
publicinterface UserDAO extends BaseDAO { Y-v6xUc{F
C-&\qAo?<:
publicList getUserByName(String name)throws A\LMmg
>o.4sN@
HibernateException; NSZ9M%7
#V@[<S2
publicint getUserCount()throws HibernateException; W2'u]1bs
`Ps&N^[
publicList getUserByPage(Page page)throws 13kl\<6
EjrK.|I0
HibernateException; ",Mr+;;:[
iU+O(vi
} qf;x~1efC4
XU_gvz
P`^nNX]x+,
-V7dSi
"\3C)Nz?
java代码: G0)}?5L1J
~7ZWtg;B
508v:?^'
/*Created on 2005-7-15*/ B 1jeIk,
package com.adt.dao.impl; 7_HFQT1.N
BlnR{Y
import java.util.List; .~u[rc|<
A`71L V%
import org.flyware.util.page.Page; 0~4Ww=#
FJCs$0
import net.sf.hibernate.HibernateException; g8kS}7/
import net.sf.hibernate.Query; jl9hFubwW
Ogv9_X8
import com.adt.dao.UserDAO; q#=HBSyM
Z-:T')#Cf
/** Y O&@
* @author Joa ~[<C6{
*/ C cPOK2
public class UserDAOImpl extends BaseDAOHibernateImpl ZmI0|r}QbY
G>=Fdt7Oc
implements UserDAO { (@m/j2z
# ~Doz7~
/* (non-Javadoc) Qp7h|<
* @see com.adt.dao.UserDAO#getUserByName .d I".L
Qo32oT[DM
(java.lang.String) y4U|~\]
*/ (@->AJF1\
publicList getUserByName(String name)throws kMJ}sS
h+=IxF4
HibernateException { }ZK%@b>
String querySentence = "FROM user in class EQN)y27poW
.' }jd#
com.adt.po.User WHERE user.name=:name"; yIhPB8QL
Query query = getSession().createQuery aq)g&.dw?
z%S$~^=b
(querySentence); Q3Pu<j}Y
query.setParameter("name", name); G9NI`]k
return query.list(); -0UR%R7q
} 793 15A
XLC9B3Jt
/* (non-Javadoc) ]DKRug5
* @see com.adt.dao.UserDAO#getUserCount() EsGf+-}|!0
*/ r4pX47H
publicint getUserCount()throws HibernateException { Qo)Da}uo20
int count = 0; 6se8`[
String querySentence = "SELECT count(*) FROM fX]`vjM{
XwUa|"X6
user in class com.adt.po.User"; cI P.5)Ca
Query query = getSession().createQuery %cLS*=MO
f";pfu_FZ
(querySentence); Tf~eH!~0
count = ((Integer)query.iterate().next VcGl8~#9
bn)1G$0|
()).intValue(); :h5G|^
return count; +N=HI1^54R
} 9wZ?")2
-=nk,cYn
/* (non-Javadoc) Mh*r)B~%[
* @see com.adt.dao.UserDAO#getUserByPage ;Ax-f04gG
q[_qZ
(org.flyware.util.page.Page) )w0x{_
*/ QuqznYSY{
publicList getUserByPage(Page page)throws tBbOxM m0
GQ;0KIN
HibernateException { u
[._RA
String querySentence = "FROM user in class 3("C'(W
Xd=KBB[r?
com.adt.po.User"; N2O *g`YC
Query query = getSession().createQuery K_;vqi^1^&
?>Sv_0
(querySentence); rz@qW2
query.setFirstResult(page.getBeginIndex()) Hl,{4%]
.setMaxResults(page.getEveryPage()); is4}s,]$6
return query.list(); sSh{.XuB+3
} }:m/@LKB
QQBh)5F
} F%h3?"s
B W<Dmn
\IE![=p\w
^1najUpQ_n
D`T;j[SsS#
至此,一个完整的分页程序完成。前台的只需要调用 rZKfb}ANQ
^ +SE_ -+]
userManager.listUser(page)即可得到一个Page对象和结果集对象 O;H6`JQ
TI'v /=;)
的综合体,而传入的参数page对象则可以由前台传入,如果用 s0/O/G?
j|t=%*
webwork,甚至可以直接在配置文件中指定。 6nZ]y&$G-k
:j]1wp+
下面给出一个webwork调用示例: LqbI/AQ)
java代码: Q#\Nhc
lS4r pbU_
VHxBs
/*Created on 2005-6-17*/ *4}_2"[
package com.adt.action.user; X:oOp=y]|
r[S(VPo[()
import java.util.List; L[x`i'0B
w"v!+~/9
import org.apache.commons.logging.Log; (QDKw}O2b
import org.apache.commons.logging.LogFactory; N1$u@P{
import org.flyware.util.page.Page; g'7E6n"!,
w:t~M[kTW
import com.adt.bo.Result; (`1io
import com.adt.service.UserService; AELj"=RA
import com.opensymphony.xwork.Action; h}
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7?*+,Fo#
/** { ADd[V
* @author Joa UzxL" `^7
*/ V|8'3=Z=
publicclass ListUser implementsAction{ <T}^:2G|
^%r6+ey
privatestaticfinal Log logger = LogFactory.getLog #EH=tJgO|J
`HX:U3/
(ListUser.class); 8A#,*@V[
Pk;\^DRC
private UserService userService; 5#GMp
(/A.,8Ad
private Page page; "w:h
g(@F`W[
privateList users; t7f(%/] H0
w?ugZYwX*
/* =\<NTu
* (non-Javadoc) B!wN%>U
* y\T$) XGV
* @see com.opensymphony.xwork.Action#execute() 2FMmANH0ev
*/ (Ceru o S
publicString execute()throwsException{ Z[#8F&QV!m
Result result = userService.listUser(page); K(+=V)'Dz
page = result.getPage(); JWNN5#=fQ
users = result.getContent(); ZFtx&vrP
return SUCCESS; C
m:AU;
} w){B$X
2j-l<!s
/** ,;pUBrz/[
* @return Returns the page. 'gY?=,dF>
*/ bJ:5pBJ3
public Page getPage(){
Va?]:Q
return page; xm{?h,U,
} QNbZ)
y4kn2Mw;
/** (dg,w*t'
* @return Returns the users. -C2!`/U
*/ 5Ew( 0K[
publicList getUsers(){ z};|.N}
return users; ~>@~U]
} =X'[r
}1 O"?6
/** ;r@=[h
* @param page @fA{;@N
* The page to set. 3HyOQD"{
*/ T={!/y+
publicvoid setPage(Page page){ !$NK7-
this.page = page; 8=D,`wog
} F:jNv3W1
9,8/DW.K
/** Wrp~OF0k
* @param users _)j\
b
* The users to set. -3ePCAtXbe
*/ k{r<S|PK0
publicvoid setUsers(List users){ @G;9eh0$
this.users = users; %vO(.A+
} .c>6}:ye
k9eyl)
/** ASdW!4.p
* @param userService w<~[ad}
* The userService to set. 8Y-*rpLy
*/ w7`pbcY,
publicvoid setUserService(UserService userService){ bGwOhd<.
this.userService = userService; jwjLxt
} [.&JQ
}
3*Q=)}
^zTe9:hz/\
bj`GGxzOb
v2tVq_\AMx
J#Q>dC7
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, vw>(JCR
?<F([(
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 _#H d2h
E-^(VZ_Xj
么只需要: 7(D)U)9h
java代码: PK|qiu-O&*
\5tG>>c i
wdt2T8`I/
<?xml version="1.0"?> 8N)Lck2PR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 4Y'Ne2M{
:ek^M (
1.0//EN" "http://www.opensymphony.com/xwork/xwork- '+Jy//5?
8VG}-
1.0.dtd"> iOfO+3'Z_U
;07$ G+['
<xwork> WI&A+1CK-5
//N="9)@
<package name="user" extends="webwork- J;<dO7 j5
_"x%s
interceptors"> @H$8;CRM
Z79 6;qk
<!-- The default interceptor stack name _'mC*7+
Ge({sy>X
--> v6DjNyg<x
<default-interceptor-ref |%5pzYe
>o13?-S%e
name="myDefaultWebStack"/> s)E8}-v
gFuK/]gzI
<action name="listUser" q_^yma
>`3F`@1L0
class="com.adt.action.user.ListUser"> F#yn'j8
<param &\ca ? #
*jQ$\|Y
name="page.everyPage">10</param> [(g2u@
<result 1p5'.~J+Q
%CYo,
e
name="success">/user/user_list.jsp</result> !"<rlB,J
</action> i._RMl5zg
1!V[fPJ
</package> oCE'@}s.i
j;48Yya'
</xwork> ._>03, "
{S+?n[1r\
&/Gn!J;1
~9APc{"A
?fP3R':s
bBc<p{
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 4Dn&+=fq
OY(CB(2N
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。 EKcPJ\7
xMQ>,nZ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 >`&2]Wc)
>&e=0@?+G
9[X'9*,
:qqG%RB
"(W;rl
我写的一个用于分页的类,用了泛型了,hoho Hmm0H6&u
tA4Ra,-c
java代码: 'OTZ&;7{
;{H Dz$
qov<@FvE0
package com.intokr.util; u59l)8=
!pRu?5
import java.util.List;
ox<&T|
T#!% Uzz
/** ,';|CGI cP
* 用于分页的类<br> K0gQr.J53
* 可以用于传递查询的结果也可以用于传送查询的参数<br> jYp!?%!
* ?AyxRbk
* @version 0.01 B\Nbt!Ps
* @author cheng "Vp
nr +6
*/ ^^b'tP1>
public class Paginator<E> { (ghI$oH
privateint count = 0; // 总记录数 iHPsRq!
privateint p = 1; // 页编号 Dj\nsc@e3
privateint num = 20; // 每页的记录数 'n'>+W:
privateList<E> results = null; // 结果 z.8/[)
/yI4;:/
/** S`kOtZ_N n
* 结果总数 D;R~!3f./b
*/ wMVUTm
publicint getCount(){ 23?u_?+4i
return count; q/b+V)V
} e8vy29\S
UePkSz9EU
publicvoid setCount(int count){
(=!At)O
this.count = count; Hhknjx
} ^2kjO/
2d.$V,U<
/** o|@0.H|
* 本结果所在的页码,从1开始 }B-$}
* 7p1Y g
* @return Returns the pageNo. jSp&\Wj b
*/ M@.l#
[@U
publicint getP(){ M_E,pg=rWI
return p; DzpWU8j
} ps<Ef
j=O+U_w
/** cpOt?XYR~
* if(p<=0) p=1 NVM_.vL
* 8Yq06o38C
* @param p MZt#T+b
*/ !{-W%=Kf
publicvoid setP(int p){ m \)B=H!bz
if(p <= 0) %tVU Rj
p = 1; Jt[ug26
this.p = p; SMZ*30i
} TDo)8+.2z
2_wpj;E
/** Wr[LC&
* 每页记录数量 4FaO+Eo,8
*/ }eLApFHEDg
publicint getNum(){ "pO
return num; 6(QfD](2}
} No7-fX1B
^&<M""Z
/** j6l1<3j
* if(num<1) num=1 -- %XkO
*/ nuq@m0t\#
publicvoid setNum(int num){ ={BC0,
if(num < 1) )|=1;L
num = 1; E 3'I;
this.num = num; WXxnOLJr
} KiXfR\S~C
fn<dr(Dx
/** ajycYk9<m
* 获得总页数 q?LOtN? o
*/ ;!HQ!#B
publicint getPageNum(){ w,IJ44f ^%
return(count - 1) / num + 1; ;}Jv4Z
} aA?Qr&]M
3N > V
sl
/** !mK()# 6
* 获得本页的开始编号,为 (p-1)*num+1 sNx_9pJs4
*/ sO) H#G
publicint getStart(){ bg|$1ue
return(p - 1) * num + 1; Kii@Z5R_?
} 8~T}BC
Pjh;;k|V
/** 76T7<.S
* @return Returns the results. -9LvAV>
*/ !
#Pn_e
publicList<E> getResults(){ pS8\ B
return results; UovN"8W+
} 2Ug_3ZuU
!Mw/j`*
public void setResults(List<E> results){ EC\@$Fg
this.results = results; ubB1a_7
} &7'=t6
;*rGZ?%*
public String toString(){ w&IYCYK_
StringBuilder buff = new StringBuilder QV."ZhL5 =
%rB,Gl:)g
(); OR&pGoW
buff.append("{"); $/^Y(0
buff.append("count:").append(count); Vw;iE=L
buff.append(",p:").append(p); f IV"U
buff.append(",nump:").append(num); :[l}Bb,
buff.append(",results:").append %x#S?GMV<
Hva!6vwO%O
(results); 8/2Wq~&
buff.append("}"); ]|F`;} 7
return buff.toString(); !=30s;-
} ecm+33C
e|C2/U-
} )Fd)YJVR
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>#dLT~[\a