Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qY0p)`3!%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]r{y+g|
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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
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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 `9%@{Ryo
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分页支持类: c:M~!CXO
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java代码: (m25ZhW
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package com.javaeye.common.util; *e!0ZB3J
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import java.util.List; P;{f+I|`
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publicclass PaginationSupport { gm\P`~+o
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publicfinalstaticint PAGESIZE = 30; c&J,O1){\
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privateint pageSize = PAGESIZE; {IJ,y27
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privateList items; .sgP3Ah
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privateint totalCount; ESft:3xyw
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privateint[] indexes = newint[0]; Wyd,7]'z)Z
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privateint startIndex = 0; ??Q'| r
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public PaginationSupport(List items, int ~sx?aiO
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totalCount){ Z`Rrv$M!
setPageSize(PAGESIZE); ?zM]p"M
setTotalCount(totalCount); xp.~i*!`
setItems(items); 3{O^q/R
setStartIndex(0); M3!A?!BU
} |9Q4VY'";
}vgeQh-G
public PaginationSupport(List items, int Z.ky=vCt
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totalCount, int startIndex){ IC"bg<L,*
setPageSize(PAGESIZE); [< Bk% B5
setTotalCount(totalCount); 9(V12gn+lk
setItems(items); }4b
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setStartIndex(startIndex); a6cq0g[# z
} Lk9X>`b#B
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public PaginationSupport(List items, int ;shhgz$
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totalCount, int pageSize, int startIndex){ %\IB_M
setPageSize(pageSize); -<h4I
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setTotalCount(totalCount); SfLZVB
setItems(items); "N>~]
setStartIndex(startIndex); D,b'1=
} FL*qV"r^n
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publicList getItems(){ ;89 `!V O
return items;
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} h fZY5+Z<
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publicvoid setItems(List items){ =bgzl=A`
this.items = items; _FR_6*C)5
} K[r<-6TS
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publicint getPageSize(){ 5+Fr/C
return pageSize; .5*5S[
} G'<:O(Imu
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publicvoid setPageSize(int pageSize){ 8T-/G9u
this.pageSize = pageSize; cuzU*QW"g
} '-c
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publicint getTotalCount(){ -|V1A[
return totalCount; imw,Nb
} "%]<Co<S
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publicvoid setTotalCount(int totalCount){ |iSd<
if(totalCount > 0){ Z$jqB~=^e
this.totalCount = totalCount; ]t0]fb[J
int count = totalCount / o?5m^S14[1
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pageSize; {02$pO
if(totalCount % pageSize > 0) c[VVCN8dA
count++; ;\a?xtIy
indexes = newint[count]; ,Y9bXC8+dU
for(int i = 0; i < count; i++){ ~P!\;S
indexes = pageSize * w]1hoYuV
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i; u|(;SY
} !r^fX=X>'
}else{ [~_)]"pU
this.totalCount = 0; 8_$[SV$q
} F^4mO|
} iepolO=
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publicint[] getIndexes(){ +q*WY*gX
return indexes; wH]5VltUT1
} Z?JR6;@W
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publicvoid setIndexes(int[] indexes){ %Yw?!GvL[
this.indexes = indexes; U/ds(*g@
} )O+V ft
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publicint getStartIndex(){ yK+1C68A
return startIndex; ( fNG51h!
} qkXnpv
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publicvoid setStartIndex(int startIndex){ <=nOyT9
if(totalCount <= 0) 2o)8 'Lp
this.startIndex = 0; d)>b/0CZ
elseif(startIndex >= totalCount) wF=?EK(;P{
this.startIndex = indexes @tT2o@2Y^
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[indexes.length - 1]; x&p.-Fi
elseif(startIndex < 0) )x5t']w`K
this.startIndex = 0; 4yK{(!&i+
else{ +L0Jje>Az
this.startIndex = indexes {<cL@W
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[startIndex / pageSize]; E4N/or
} DbWaF5\yD
} <>v=jH|L
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publicint getNextIndex(){ l"zwH
int nextIndex = getStartIndex() + XgI;2Be+&a
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pageSize; *q&^tn b
if(nextIndex >= totalCount) ;{lb_du2:
return getStartIndex(); ~Z`Cu~7
else '[Zgwz;z
return nextIndex; I3qTSX-
} I|x?
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publicint getPreviousIndex(){ f/95}6M
int previousIndex = getStartIndex() - &M>o
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pageSize; [CG3&J
if(previousIndex < 0) 1SF8D`3
return0; 0fJz[;dV>n
else mWUkkR(/
return previousIndex; prEI9/d"
} ZS<`.L6B3
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} KwHlpW*
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抽象业务类 u|"y&>!R-
java代码: lFtH;h,==v
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/** 6$)FQ
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* Created on 2005-7-12 8'PK}heBU
*/ 2#(dfEAy
package com.javaeye.common.business; 0Ke2%+yqJ
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import java.io.Serializable; _v[gJ(F
import java.util.List; <2af&-EGs
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import org.hibernate.Criteria; XL7||9,(h
import org.hibernate.HibernateException; '=0l{hv@
import org.hibernate.Session; TKp2C5bX
import org.hibernate.criterion.DetachedCriteria; '':MhRb
import org.hibernate.criterion.Projections; !bIE%cq
import B[IWgvB(e
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org.springframework.orm.hibernate3.HibernateCallback; a9u2Wlz
import
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org.springframework.orm.hibernate3.support.HibernateDaoS KV)if'
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upport; I~GHx5Dk
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import com.javaeye.common.util.PaginationSupport; )(9[> _+40
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public abstract class AbstractManager extends Jcy+(7lE)
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HibernateDaoSupport { LGK&&srJs
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privateboolean cacheQueries = false; Y(u`K=*
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privateString queryCacheRegion; VAo`R9^D#
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publicvoid setCacheQueries(boolean aoQ$"PF9
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cacheQueries){ Y2IMHNtH
this.cacheQueries = cacheQueries; $V !25jQ
} ik](k"1{
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publicvoid setQueryCacheRegion(String i&%m^p
+ 9I|Fm
queryCacheRegion){ LzxO=+=9!q
this.queryCacheRegion = 8|(],NyEJ
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queryCacheRegion; 4jc?9(y%
} nu)YN1
*
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publicvoid save(finalObject entity){ *aJO5&w<T
getHibernateTemplate().save(entity); |e<$
} 9 p,O>I
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publicvoid persist(finalObject entity){ ;b(ww{&
getHibernateTemplate().save(entity); {1_<\~J
} Xr:s-L
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publicvoid update(finalObject entity){ .SLpgYFL{
getHibernateTemplate().update(entity); (xE |T f
} uq/Fapl
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publicvoid delete(finalObject entity){ ##%&*vh
getHibernateTemplate().delete(entity); cF_`QRtO
} Dlpmm2
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publicObject load(finalClass entity, P,xIDj4d
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finalSerializable id){ sH>`eqY
return getHibernateTemplate().load puLgc$?
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(entity, id); ]Ok'C"V(j
} :T|9;2
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publicObject get(finalClass entity, %NfXe[T
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finalSerializable id){ +hKs
return getHibernateTemplate().get `!spi=f
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(entity, id); r{B28'f[
}
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publicList findAll(finalClass entity){ w3 kkam"
return getHibernateTemplate().find("from vaJl}^T
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" + entity.getName()); TtF+~K
} lT*@f39~g
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publicList findByNamedQuery(finalString [V>s]c<4`o
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namedQuery){ PU[<sr#,
return getHibernateTemplate ^^zj4 }On?
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().findByNamedQuery(namedQuery); 0w:
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} 97UOH
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publicList findByNamedQuery(finalString query, d3|/&gDBK
)[J@s=
finalObject parameter){ :8]8[
return getHibernateTemplate AorY#oq
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().findByNamedQuery(query, parameter); o2=):2x
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} S0Io$\ha
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publicList findByNamedQuery(finalString query, U<Tv<7`
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finalObject[] parameters){ y631;dU
return getHibernateTemplate E
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().findByNamedQuery(query, parameters); p"c6d'qe
} SMIDW}U2S
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publicList find(finalString query){ 6dmb
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return getHibernateTemplate().find J4"A6`O
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(query); <tBT?#C9+
} l^}u S|c(
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publicList find(finalString query, finalObject ?P-O4
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parameter){ W^h,O+vk
return getHibernateTemplate().find fkp(M
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(query, parameter); [uHU[
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} (3mL!1\
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public PaginationSupport findPageByCriteria @2L^?*n=
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(final DetachedCriteria detachedCriteria){ rh1PpsSc
return findPageByCriteria @wa"pWx8
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); F<4:P=
} K<:%ofB"S
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public PaginationSupport findPageByCriteria |f @A-d X
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(final DetachedCriteria detachedCriteria, finalint Pe,k y>ow
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startIndex){ MymsDdQ]
return findPageByCriteria -k7b#
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(detachedCriteria, PaginationSupport.PAGESIZE, j@(S7=^C6%
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startIndex); ~`&4?c3p
} %;h1n6=v2
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public PaginationSupport findPageByCriteria Cip|eM &l
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(final DetachedCriteria detachedCriteria, finalint C(v'7H{4cW
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pageSize, z+;$cfN
finalint startIndex){ [[^r;XKQ
return(PaginationSupport) >^`# %$+
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getHibernateTemplate().execute(new HibernateCallback(){ [dP<A?s
publicObject doInHibernate i^jM9MAi
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(Session session)throws HibernateException { Od;k}u6;<
Criteria criteria = D$)F
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detachedCriteria.getExecutableCriteria(session); EH2):
int totalCount = M5+R8ttc
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((Integer) criteria.setProjection(Projections.rowCount <ZZfN@6
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()).uniqueResult()).intValue(); J+ :3==,
criteria.setProjection xC _3&.
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(null); HI D6h!
List items = 8M!9gvcaO
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criteria.setFirstResult(startIndex).setMaxResults KS~Q[-F1P
'!Va9m*w7
(pageSize).list(); F czia0@z
PaginationSupport ps = #Qz9{1\G
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new PaginationSupport(items, totalCount, pageSize, Lp$&eROFVs
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startIndex); gf9,/m
return ps; rM~Mqpk
} l@UF-n~[
}, true); -6F\=
} b9.7j!W
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public List findAllByCriteria(final /8_x]Es/
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DetachedCriteria detachedCriteria){ tx1TtWo
return(List) getHibernateTemplate uKIR$n"
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().execute(new HibernateCallback(){ -t`KCf,0
publicObject doInHibernate 65&+Fv
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(Session session)throws HibernateException { P6^\*xkMr
Criteria criteria = #c<F,` gdi
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detachedCriteria.getExecutableCriteria(session); ,5*<C'9
return criteria.list(); ABtv|0K
} W7V#G(cpU
}, true); 0R+<^6^l)
} zBrqh9%8e
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public int getCountByCriteria(final /4*>.Nmb,f
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DetachedCriteria detachedCriteria){ 4%jSqT@
Integer count = (Integer) a!x?Apww
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getHibernateTemplate().execute(new HibernateCallback(){ [DSzhi]
publicObject doInHibernate U3>ES"N
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(Session session)throws HibernateException { ;2eZa|M*q
Criteria criteria = t_X=x`f
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detachedCriteria.getExecutableCriteria(session); -S$Y0FDV
return 9@p+g`o
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criteria.setProjection(Projections.rowCount Bd13p_V"6
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()).uniqueResult(); 6k\8ulHw
} H]f8W]"c[
}, true); 9[\$\l
return count.intValue(); "g;}B"rG
} iJ`v3PP
} oJ}$ /_
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用户在web层构造查询条件detachedCriteria,和可选的 |f&=9%
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ApAHa]Ccp
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PaginationSupport的实例ps。 Jp`qE
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ps.getItems()得到已分页好的结果集 '^6x-aeq[D
ps.getIndexes()得到分页索引的数组 {BJn9B
ps.getTotalCount()得到总结果数 tJY3k$YX
ps.getStartIndex()当前分页索引 3/((7O[
ps.getNextIndex()下一页索引 ]^CNC0
ps.getPreviousIndex()上一页索引 IOOAaa @(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 2f$6}m'Ad
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 =XT}&D6
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一下代码重构了。 ,] ,dOIOwn
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我把原本我的做法也提供出来供大家讨论吧: nZ2mY!*
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首先,为了实现分页查询,我封装了一个Page类: H#;-(`F
java代码: 5 J9,/M0
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/*Created on 2005-4-14*/ Bzw!,(u/
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package org.flyware.util.page; dLMKfh/4Q
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/** tb-:9*2j-
* @author Joa u/BCl!`
* 80M"`6
*/ 8 3wa{m:
publicclass Page { KGsH3{r
p|z\L}0
/** imply if the page has previous page */ 5xawa:K
privateboolean hasPrePage; VSlIeZ
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/** imply if the page has next page */ .*s1d)\:
privateboolean hasNextPage; IE-c^'W=}m
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/** the number of every page */ q >|:mXR
privateint everyPage; Wa{>R2h\
sacaL4[_<
/** the total page number */ y[s* %yP3l
privateint totalPage; aD1G\*AFJ
<d GGH
/** the number of current page */ I'h6!N"
privateint currentPage; 6mnj!p]3
JEK6Ms;)A
/** the begin index of the records by the current 9oK#n'hjb
#mNM5(o
query */ #l6L7u0~wC
privateint beginIndex; i 5"g?Wa2N
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/** The default constructor */ F8J;L](Dq
public Page(){ ztNm,1pnQ
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} "0F =txduS
R)AFaP |
/** construct the page by everyPage .~+I"V{yF
* @param everyPage P| o_/BS
* */ >g!a\=-[
public Page(int everyPage){ <|_/i/H
this.everyPage = everyPage; I@ l'Fx
} J
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/** The whole constructor */ -vcHSwGb
public Page(boolean hasPrePage, boolean hasNextPage, 2t3'"8xJ
-0 [^w
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int everyPage, int totalPage, )&"l3*x
int currentPage, int beginIndex){ {%$eq{~m
this.hasPrePage = hasPrePage; $= '_$wG
8
this.hasNextPage = hasNextPage; 85rXm*Df
this.everyPage = everyPage; }LDH/#
u
this.totalPage = totalPage; #2thg{5
this.currentPage = currentPage; }[P1Va[!
this.beginIndex = beginIndex; iV!o)WvG,F
} }ZMbTsm
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/** ?\dY!
* @return d`D<PT(\
* Returns the beginIndex. S3V3<4CB
*/ .0l0*~[
publicint getBeginIndex(){ Bb^CukS:
return beginIndex; )~1QOl
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} PN ,pEk|
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/** *ip2|2G$
* @param beginIndex &ah!g!o3
* The beginIndex to set. _T6l*D
*/ 6/ir("LK
publicvoid setBeginIndex(int beginIndex){ 9Xb,Swo~
this.beginIndex = beginIndex; 5?+ECxPt
} RF/I*5
H#IJ&w|
/** i1]*5;q
* @return |^K-m42
* Returns the currentPage. 8_8r{a<xW
*/ h}&WBN
publicint getCurrentPage(){ a?bSMt}
return currentPage; C~PrIM?
} (H/JB\~r
\ct) /
/** Ek|#P{!
* @param currentPage B#RwW,
* The currentPage to set. bD_|n!3
*/ >U\,(VB
publicvoid setCurrentPage(int currentPage){ '_& Xemz
this.currentPage = currentPage; q_eGY&M
} 2GNtO!B.
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/** j4j %r(
* @return g4,>cqRkq
* Returns the everyPage. ydo"H9NOS
*/ (q'w"q j
publicint getEveryPage(){ FB{4& ;
return everyPage; 07WZ w1(;
} %Q:i6 ~
&WN#HI."]
/** fZU#%b6G
* @param everyPage qkB)CY7
* The everyPage to set. hA1\+r
*/ f\O)+Vc
publicvoid setEveryPage(int everyPage){ \ .HX7v
this.everyPage = everyPage; ~|+!xh
} x&qC~F*QR%
e;KZTH;
/** `6:;*#jO,
* @return >%jQw.
* Returns the hasNextPage. r8\"'4B1
*/ SE=3`rVJ
publicboolean getHasNextPage(){ F3*]3,&L
return hasNextPage; gJn|G#!
} d&K2\n
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/** fpbb <Ro
* @param hasNextPage KLv`Xg \
* The hasNextPage to set. '^f,H1oW
*/ !~5;Jb>s[/
publicvoid setHasNextPage(boolean hasNextPage){ o~7~S
this.hasNextPage = hasNextPage; q]F2bo
} '@1o M1
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/** PM3kI\:)m
* @return 2O\p`,.
* Returns the hasPrePage. lA[BV7.=7
*/ L{fKZ
publicboolean getHasPrePage(){ 69{^Vfd;Y
return hasPrePage; h=6Zvf<x
} 6 R}]RuFQ
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/** R$(FrbC
* @param hasPrePage IQ_2(8Kv
* The hasPrePage to set. @,
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*/ 7PG&G5
publicvoid setHasPrePage(boolean hasPrePage){ _:oB#-0
this.hasPrePage = hasPrePage; Vae}:8'}
} H8d%_jCr
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/** *Dx&} "
* @return Returns the totalPage. h3rdqx1
* rEwEdyK
*/ s=0z%~H
publicint getTotalPage(){ [DS.@97n
return totalPage; dh r)ra]
} /wplP+w2
uan%j]|q%
/** 2pR+2p`
* @param totalPage $'D|}=h<Y
* The totalPage to set. wZ7Opm<nt
*/ |F)BKo D
publicvoid setTotalPage(int totalPage){ }F3}-5![
this.totalPage = totalPage; $10"lM[
} OwXw9
l{tpFu9v
} ;T1OXuQ
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;&mefaFlWp
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 'qR)f\em
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个PageUtil,负责对Page对象进行构造: D@9adwQb
java代码: uE {r09^q\
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/*Created on 2005-4-14*/ *E$&
package org.flyware.util.page; `[)
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import org.apache.commons.logging.Log; CUIFKM
import org.apache.commons.logging.LogFactory; NDsF<2A4
p0c*)_a*
/** )1#J4
* @author Joa fpd4 v|(
* .gZ1}2GF=
*/ 62L,/?`B$
publicclass PageUtil { TsiI5'tx
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privatestaticfinal Log logger = LogFactory.getLog ScN'|Ia.-
=i'APeNaQ
(PageUtil.class); -8Z;s8ACo
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/** *@;Pns]L-
* Use the origin page to create a new page .7GTL
* @param page <L!9as]w
* @param totalRecords /6Bm
<k%
* @return pi?$h"y7Q
*/ 3MqyHOOv
publicstatic Page createPage(Page page, int "rHcsuSEw
MS7rD%(,'
totalRecords){ utSW>
return createPage(page.getEveryPage(), tfz"9PV80
?$v*_*:2h
page.getCurrentPage(), totalRecords); 0j\} @
} T?lp:~d
j Wpm"C
/** Ms>CO7Nvy
* the basic page utils not including exception Ja4j7d1:
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handler
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* @param everyPage $?Dcp^
* @param currentPage lf`" (:./
* @param totalRecords zWO!z=
* @return page Z;'5A2
*/ uW 7Yem&
publicstatic Page createPage(int everyPage, int {JGXdp:SB
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currentPage, int totalRecords){ .DrGr:UW
everyPage = getEveryPage(everyPage); O3/w@q Q
currentPage = getCurrentPage(currentPage); f%[0}.wp
int beginIndex = getBeginIndex(everyPage, c3aBPig\D
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currentPage); %(}%#-X
int totalPage = getTotalPage(everyPage, ]broU%#"
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totalRecords); xofxE4.
boolean hasNextPage = hasNextPage(currentPage, q9gk:Jt
16-1&WuY@
totalPage); V*,6_-^l
boolean hasPrePage = hasPrePage(currentPage); 1sNZl&
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returnnew Page(hasPrePage, hasNextPage, =Sjf-o1V
everyPage, totalPage, ?910ki_
currentPage, %|(Cb!ySX
0Qr|!B:+9)
beginIndex); b O9PpOk+z
} J;5G]$s
!*!i&0QC~R
privatestaticint getEveryPage(int everyPage){ k
& 6$S9
return everyPage == 0 ? 10 : everyPage; "ivSpec.V
} |'QgL0?
gg?O0W{
privatestaticint getCurrentPage(int currentPage){ Z}`A'#!
return currentPage == 0 ? 1 : currentPage; uB;PaZG?{
} 5E!Wp[^
fq(3uE]nC
privatestaticint getBeginIndex(int everyPage, int F7&Oc)f"B
7Um3myXU
currentPage){ \E8CC>Jd
return(currentPage - 1) * everyPage; &`B
Tw1u
} F* _ytL
83pXj=k<
privatestaticint getTotalPage(int everyPage, int i:sb_U+M
#@Rtb\9
totalRecords){ !{S HlS
int totalPage = 0; ^$;5ZkQy
O[5u6heNMr
if(totalRecords % everyPage == 0) "vF7b|I
totalPage = totalRecords / everyPage; Eemk2>iP?
else "%dok@v
totalPage = totalRecords / everyPage + 1 ; /_ RrNzqy
FQBAt0
return totalPage; +8 }p-<a
} ~PA6e+gmL
/9<62F@zJ"
privatestaticboolean hasPrePage(int currentPage){ v]U0@#/p
return currentPage == 1 ? false : true; r!)jxIL\
} 6B&ERdoX
lQt* LWd[
privatestaticboolean hasNextPage(int currentPage, v0W/7?D
8gXf4A(N
int totalPage){ #TD0)C/
return currentPage == totalPage || totalPage == oF=UjA
u= ydX
0 ? false : true; mAuN* (
} ;2Za]%'
9Fh1rZD<
y R_x:,|g
} }x+s5a;!3/
ds<q"S{p
{f[X)
f4lC*nCN
k%h%mz
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。 t_{rKb,
t'DYT"3
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 J/ZC<dkYQ
#(o( p
做法如下: ]?n~?dD{]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /]hE?cmj
3PRK.vf
的信息,和一个结果集List: /+{1;}AT
java代码: Tj+U:#!!~
e.fxB
t N4-<6
/*Created on 2005-6-13*/ aYM~Ub:x{
package com.adt.bo; 8erG](
I&`aGnr^^
import java.util.List; *4%%^*g.I
Q%524%f$
import org.flyware.util.page.Page; I%NeCd
p`EgMzVO,
/** Eu<f
* @author Joa *5{1.7
*/ #8~ygEa}
publicclass Result { qWf[X'
iCCe8nK
private Page page; P@D\5}*6
DP;:%L}
private List content; UyFC\vQ
d2TIG<6/
/** C_JO:$\rE
* The default constructor 5nTcd@lX
*/ qoZ)"M
public Result(){ EM`'=<)V
super(); =iH9=}aBFC
} /;{L~f=et)
Gpi_p
/** +TX4,"
* The constructor using fields ={f8s,m)P,
* ^;F5ymb3U
* @param page eoXbZ
* @param content \98N8p;,I
*/ A3*(c3
public Result(Page page, List content){ O /:FY1
this.page = page; i+pQ 7wx
this.content = content; (&v,3>3]
} 0Lb{HLT
Ftd,dqd
/** ,LP^v'[V7
* @return Returns the content. a>rDJw:
*/ e6bh,BwgQq
publicList getContent(){ qj `C6_?
return content; *A4eYHn@
} AJE$Z0{q
jVZ<i}h0B
/** 0TSB<,9a[
* @return Returns the page. 4Gh\T`=
*/ 4=EA3`l
public Page getPage(){ F_m'
9KX4E
return page; U^BM 5b
} 0
x' d^
0FY-e~xr
/** Jp%5qBS^
* @param content V"'PA-z3
* The content to set. 6y1\ar(A
*/ V0#Ocq,
public void setContent(List content){ =6O*AJ
this.content = content; T:Ee6I 3l
} &"I csxG
%[s%H)e)
/** "tl$JbRTY
* @param page GN9kCyPK
* The page to set. M8<Vd1-5
*/ 3u4Q!U%(D
publicvoid setPage(Page page){ @SpP"/)JY
this.page = page; {V[}#Mf
} |#M|"7;2z
} Gyy4zK
hjM?D`5x
P\<:.8@$S
yz=X{p1
\!BVf@>p%
2. 编写业务逻辑接口,并实现它(UserManager, M@<9/xPS
3l41"5Fy&
UserManagerImpl) ,Kl?-W@
java代码: 6]d]0TW_
*o4a<.hd2
KR%WBvv
/*Created on 2005-7-15*/ g#^MO]pY
package com.adt.service; |:JT+a1
1' v!~*af
import net.sf.hibernate.HibernateException; Ez0zk9
^]D1':
import org.flyware.util.page.Page; (.V),NKG
i,a"5DR8
import com.adt.bo.Result; h]k$K
.#$2,"8
/** P/|1,Sk
* @author Joa A)>#n)
*/ {vCtp
publicinterface UserManager { i2c|_B
Z%:>nDZV
public Result listUser(Page page)throws ],S {?!'1
ByJPSucD
HibernateException; ktx| c19
rf:H$\yw
} PWiUW{7z
OQB7C0+ &
#0[^jJ3J
@r/~Y]0Ye5
\rzMgR$/rj
java代码: CssE8p>"F
6X%g-aTs
lYJSg70P
/*Created on 2005-7-15*/ @;P ;iI
package com.adt.service.impl; !p/?IW+
HdI)Z<Krp
import java.util.List; A8Q^y
AP^
FZj>N(
import net.sf.hibernate.HibernateException; a~$Y;C_#<
!h7.xl OpN
import org.flyware.util.page.Page; @e
GBF
Ns
import org.flyware.util.page.PageUtil; Gb\PubJ
Coe/ 4!$M
import com.adt.bo.Result; mA+:)?e5~
import com.adt.dao.UserDAO; }}QR'
import com.adt.exception.ObjectNotFoundException; pOo016afmA
import com.adt.service.UserManager; {XmCG%%L
C\GP}:[T3
/** KRC"3Qt
* @author Joa jTcv&`fAz
*/ #6<1
=I'j
publicclass UserManagerImpl implements UserManager { Pa{
V>`ANZ4
private UserDAO userDAO; ~EPVu
`IUn{I
/** JN|6+.GG
* @param userDAO The userDAO to set. ~E7IU<B
*/ \toU zTT
publicvoid setUserDAO(UserDAO userDAO){ QE\
[EI2
this.userDAO = userDAO; i9DD)Y<
} QH9t |l
]2wxqglh)
/* (non-Javadoc) |
:-i[G?n
* @see com.adt.service.UserManager#listUser Wjw,LwB
VIP7j(#t_g
(org.flyware.util.page.Page) W-n4wIj"
*/ !ka* rd
public Result listUser(Page page)throws 4?'vP '
6p)AQTh>
HibernateException, ObjectNotFoundException { dWvVK("Wj
int totalRecords = userDAO.getUserCount(); WQ.0} n}d
if(totalRecords == 0) +y?Ilkk;j
throw new ObjectNotFoundException r[a7">n
>Q\Kc=Q|
("userNotExist"); TQF+aP8[L
page = PageUtil.createPage(page, totalRecords); 7#0buXBg
List users = userDAO.getUserByPage(page); `.W2t5Y
returnnew Result(page, users); V}#X'~Ob
} :eVZ5?F
t~->&Ja
} -Lh7!d
TJO$r6&
tX{yR'Qhu
9Ux(
P2-&Im`+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rG-T Dm
/uwi$~Ed
询,接下来编写UserDAO的代码: s{Z)<n03
3. UserDAO 和 UserDAOImpl: esqmj#G
java代码: -Z"4W
lT^su'+bk
$oK&k}Q
/*Created on 2005-7-15*/ 50^ux:Uv+N
package com.adt.dao; mH'~pR>t
/o;M
?Nt6
import java.util.List; -Uwxmy +
;.A}c)b
import org.flyware.util.page.Page; `@/)S^jBau
%c }V/v_h
import net.sf.hibernate.HibernateException; *VZ|Idp
kJWg},-\
/** dZU#lg
* @author Joa ')y2W1
*/ o|kykxcq
publicinterface UserDAO extends BaseDAO { i}) s4%a
@NiuT%#c
publicList getUserByName(String name)throws ;o_F<68QP
Ax;[ Em?I
HibernateException;
54+(o6E<
+1ICX
publicint getUserCount()throws HibernateException; f!9i6
~dYCY_a
publicList getUserByPage(Page page)throws j[G`p^ul
CL=%eSsuD
HibernateException; b(iF0U>&
#S}orWj
} u^"
I3u8$
<RGH+4LF
u "[f\l
<^5!]8*O
#,%bW[L<N
java代码: Nd~B$venh
yqT !A
ge~@}iO@
/*Created on 2005-7-15*/ IiU> VLa
package com.adt.dao.impl; {q-&!l|
d*@T30
import java.util.List; ujU,O%.n
wPlM=
.Hq?
import org.flyware.util.page.Page; Hn|W3U
VW-qQe
import net.sf.hibernate.HibernateException; R'>!1\?Iq
import net.sf.hibernate.Query; (8duV
@!sK@&ow@%
import com.adt.dao.UserDAO; *WwM"NFHDd
,;k+n)
/** UcRP/LR%C
* @author Joa FK%b@/7s~
*/ W }NUU
public class UserDAOImpl extends BaseDAOHibernateImpl Pfd1[~,
YF%gs{
implements UserDAO { ~6G
`k^!
-+R,="nRQ
/* (non-Javadoc) q+ax]=w
* @see com.adt.dao.UserDAO#getUserByName w#A)B<Y/"
*uvM6F$ut
(java.lang.String) ;Afz`Se1@
*/ vy<W4
publicList getUserByName(String name)throws )U/jD
w"hd_8cO
HibernateException { o! a,r3
String querySentence = "FROM user in class JcAsrtrG]
gabfb#
com.adt.po.User WHERE user.name=:name"; ?nU<cx h
Query query = getSession().createQuery ]aX@(3G1s
c*bvZC^6
(querySentence); inut'@=G/
query.setParameter("name", name); 55S s%$k@
return query.list(); 6^`iuC5
} [doEArwn
Pv -4psdw
/* (non-Javadoc) O]N /(pe:d
* @see com.adt.dao.UserDAO#getUserCount() u]p21)m$x
*/ X8C7d6ca
publicint getUserCount()throws HibernateException { Jf YgZ\#
int count = 0; <BR^Dv07U
String querySentence = "SELECT count(*) FROM 'zyw-1
/%@;t@BK4
user in class com.adt.po.User"; G m~ ./-
Query query = getSession().createQuery 5EYGA\
*+M#D^qo
(querySentence); !KHgHKEW^
count = ((Integer)query.iterate().next }b_Ob
3>O|i2U
()).intValue(); dN8Mfa)
return count; RQVu~7d[
} VAPeMO
ck
cu!%aM,/<-
/* (non-Javadoc) pH'_k k
* @see com.adt.dao.UserDAO#getUserByPage "@V yc6L
VfU"%0x
(org.flyware.util.page.Page) wgl <JO
*/ `TBXJ(Y
publicList getUserByPage(Page page)throws ASqYA1p.
{
I#>6
HibernateException { X[B P0:`t
String querySentence = "FROM user in class PK|-2R"M
Yy *=@qu>g
com.adt.po.User"; <-VBb[M#
Query query = getSession().createQuery mixsJ}e
rA~f68h|
(querySentence); R%UTYRLUn
query.setFirstResult(page.getBeginIndex()) @*z"Hi>4
.setMaxResults(page.getEveryPage()); 10SI&O
return query.list(); bRAD_
} nCQtn%j't
VF`!ks
} l5 9a3=q
{&5lZ<nu8A
wQ33Gc
>Hf{Mx{<
ACRuDY
至此,一个完整的分页程序完成。前台的只需要调用 {JE [
#Y7jNrxE
userManager.listUser(page)即可得到一个Page对象和结果集对象 %8*:VR
sT^R0Q'>
的综合体,而传入的参数page对象则可以由前台传入,如果用 /VYT](
:nx+(xgw
webwork,甚至可以直接在配置文件中指定。 eF+F"|1h
~$J;yo~
下面给出一个webwork调用示例: s~M$Wo8
java代码: L}h_\1
<6UXk[y
[)"\Aq
/*Created on 2005-6-17*/ |
0
package com.adt.action.user; -1Q24jrO-
q T6y&
import java.util.List; D{(}&8a9
ajSB3}PN
import org.apache.commons.logging.Log; Y`g o V
import org.apache.commons.logging.LogFactory; :\^b6"}8
import org.flyware.util.page.Page; D ,kxB~
#`iEb iSq
import com.adt.bo.Result; Y 9$jJ1V
import com.adt.service.UserService; ~1O|4mssS
import com.opensymphony.xwork.Action; \F|)w|v
'+9<[]
/** od=hCQ1>
* @author Joa orjtwF>^
*/
p9"dm{
publicclass ListUser implementsAction{ UT;%I_i!'
o`YBz~2
privatestaticfinal Log logger = LogFactory.getLog '{
<RX
x?S86,RW
(ListUser.class); FX!KX/OE)
|[`YGA4
private UserService userService; !)bZ.1o
ZiPeP
private Page page; x?L0R{?WW
d6n_Hpxw^
privateList users; NjIPHM$g
Y(UK:LZ'
/* G_+/ e]P
* (non-Javadoc) ,
>7PG2
a
* i^DMnvV.
* @see com.opensymphony.xwork.Action#execute() wUaWF$~y
*/ u8c@q'_
publicString execute()throwsException{ &~*](Ma
Result result = userService.listUser(page); d88A.Z3w
page = result.getPage(); CcQc!`YC
users = result.getContent(); l8G1N[
return SUCCESS; KKC%!Xy
} NtM>`5{?
f2e;N[D
/** F0!Z1S0g
* @return Returns the page. 9"#C%~=+
*/ v~ >Bbe
public Page getPage(){ ,:mL\ZED
return page; `,}7LfY
} ^BA
I/WP
_eGYwBm
/** SZH`-xb!+5
* @return Returns the users. /B t!xSI
*/ 26p[x'W
publicList getUsers(){ !7DDPJ~
return users; NF0_D1Goi
} #G#gc`S-,
=\lw.59
/** # Wi?I=,
* @param page o8X_uKEI
* The page to set. GST#b6S
*/ @_kF&~
publicvoid setPage(Page page){ x3i}IC
this.page = page; lpXGsKH2
} hJ(vDv%
Z[Tou
/** u\Cf@}5(
* @param users R=~%kt_n
* The users to set. y"yo\IDW
*/ qb[hKp5K6
publicvoid setUsers(List users){ P4@`C{F5m
this.users = users; 1r=cCM
} J$}]p
Po58@g
/** l:'#pZ4T
* @param userService 0!,uo\`
* The userService to set. =.z;:0]'n
*/ Wxj_DTi[1"
publicvoid setUserService(UserService userService){ bL
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this.userService = userService; aVu!Qk=Z/
} SE\?8cs]-
} 5QiQDQT}5
!'H$08Ql}
hdDT'+
'4uu@?!dVk
R%KF/1;/
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, b*Y Wd3
G:1d6[Q5{
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 S46aUkW.
O[VY|.MEk
么只需要: O&<p
8
java代码: 1dLc/,|
(T*$4KGV
OK]Q Db
<?xml version="1.0"?> 6C2~0b
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]JkEf?;.
u{DEOhtI4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- estiS
~5+RK16
1.0.dtd"> YH\9Je%jx
y.lWyH9
<xwork> |OJWQU![by
(=^KP7
<package name="user" extends="webwork- "jAd.x?X7e
qm$(_]R~`
interceptors"> :\|A.#
U
nsI+04[F
<!-- The default interceptor stack name l
L;5*@
@e<(o
UE
--> Qn8xe,
<default-interceptor-ref ASHU0v
Y5tyFi#w[
name="myDefaultWebStack"/> iv >MIdIm
#VrIU8Q7'
<action name="listUser" srf}+>u&
0S4BV%7F
class="com.adt.action.user.ListUser"> os{ iY
<param ol"|?*3q
kY$EK]s
name="page.everyPage">10</param> mxqD'^n#
<result Mm$\j*f/
(|BY<Ac3
name="success">/user/user_list.jsp</result> E<\$3G-do
</action> bqED5;d'#
i3,.E]/wX@
</package> KZjh<sjX|
~bZ=]i
</xwork> 0cycnOd
m}'_Poc
g$s;;V/8e
ZHK>0>;
O#U maNj/
."+lij=56
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 ~gpxK{
Kd-1EU
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。
-qj[ck(y
rk8pL[|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 r""rJzFz'
!uGfS' Vl
Q7uJ9Y{X
96^aI1:
nW)+-Wxq
我写的一个用于分页的类,用了泛型了,hoho /i"hViCrlG
&q>8D'
java代码: 6=;:[
$/M-@3wro
Z
i6s0Uck
package com.intokr.util; hty'L61\z
fLe~X!#HF
import java.util.List; ZoXz@/T
z&gmaYwq
/** (S!UnBb&
* 用于分页的类<br> `2 <:$]
* 可以用于传递查询的结果也可以用于传送查询的参数<br> itzUq,T
* B2[f1IMI
* @version 0.01 ~Y/A]N86,
* @author cheng 6nk}k]Ji
*/
^f,4=-
public class Paginator<E> { !Axe}RD'
privateint count = 0; // 总记录数 8QTry%
privateint p = 1; // 页编号 ~3 :VM_
privateint num = 20; // 每页的记录数 D
5r H6*J
privateList<E> results = null; // 结果 i%9vZ
)5b_>Uy
/** \( s `=(t
* 结果总数 FFqK tj's
*/ kD#n/RBgf
publicint getCount(){ \< .BN;t{
return count; y[XD=j
} st)is4
^i8,9T'=
publicvoid setCount(int count){ q8$t4_pF
this.count = count; NAD^10
} ~5HT_B U=
y8$3kXh
/** |1%%c
%
* 本结果所在的页码,从1开始 t+KW=eW
* `NQ
* @return Returns the pageNo. futYMoV
*/ %AO6=
publicint getP(){ 9&*
7+!
return p; E,m|E]WP
} pX_
Dd1k?
/** ?r !kKMZ
* if(p<=0) p=1 sa+
JN^[X
* h-PJC/>
* @param p MUl`0H"tR
*/ =Q9^|& 6
publicvoid setP(int p){ SPV+ O{
if(p <= 0) '^)'q\v'k
p = 1; sc]#T)xG
this.p = p; qefp3&ls
} Gt*<Awn8
:z8/iD y
/** >3/mV<g f
* 每页记录数量 'f{13-#X@
*/ q(qm3OxYo
publicint getNum(){ c= t4 gf
return num; C?|sQcCE
} }p?,J8=-
l?)>"^
/** ahXcQ9jzFi
* if(num<1) num=1 KRxJ2
*/ G|jHic!
publicvoid setNum(int num){ >l 0aME@-0
if(num < 1) (/uN+
num = 1; #+o$Tg
this.num = num; 1vq2`lWpx
} WuE]pm]c
igQzL*X
/** j(y<oxh
* 获得总页数 #MYoy7=
*/ i]<@
publicint getPageNum(){ ,u|>%@h
return(count - 1) / num + 1; V<WWtu;3
} zmQQ/7K
8(n>99VVK
/** 'ij+MU1
* 获得本页的开始编号,为 (p-1)*num+1 ,IhQ %)l
*/ cy@oAoBq
publicint getStart(){ C5(XZscq
return(p - 1) * num + 1; #fF5O2E'3
} ?xwi2<zz
y"H5>
/** J?{sTj"KB
* @return Returns the results. 6/cm TT$i
*/ ED8{
publicList<E> getResults(){ (tA[] ne2
return results; jkl dr@t
} _8$xsj4_
A@~9r9Uf
public void setResults(List<E> results){ pzRVX8
this.results = results; jy~hLEt7
} Uhvy2}w
YN)qMI_`A
public String toString(){ >0SG]er@
StringBuilder buff = new StringBuilder |34k;l]E
2.nT k
(); IgJG,!>h
buff.append("{"); |d&Kr0QIV
buff.append("count:").append(count); c*#$sZ@YA
buff.append(",p:").append(p); d0T 8Cwcb
buff.append(",nump:").append(num); c
k[uvH
buff.append(",results:").append )PR`irw
<,O|fY%
(results); yUcU-pQ
buff.append("}"); 4%}iKoT
return buff.toString(); G-D}J2r=F
} Ox
,Rk
.&5 3sJ0{
} R1hmJ
A]iT
uu5 p
kK6t|Yn&