Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4~YPLu
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1`z^Xk8vt
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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 yB~`A>~M
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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 etk@ j3#
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分页支持类: [sF
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java代码: ~:M"JNcs
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package com.javaeye.common.util; T~"T%r
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import java.util.List; rs?"pGz;
@M!WosRk
publicclass PaginationSupport { c6"hk_
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publicfinalstaticint PAGESIZE = 30; 1P1"xT
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privateint pageSize = PAGESIZE; 1O{x9a5Z?O
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privateList items; 5^W},:3R
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privateint totalCount; Jfs$VGZP;
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privateint[] indexes = newint[0]; q;{# ~<"+
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privateint startIndex = 0; 7[}K 2.W.
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public PaginationSupport(List items, int 1tMs\e-
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totalCount){ }&I^1BHZs
setPageSize(PAGESIZE); k@i+gV%
setTotalCount(totalCount); @=kDaPme92
setItems(items); /^F$cQX(
setStartIndex(0); ]IZn#gnM
} ',<Bo{
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public PaginationSupport(List items, int ?-g/hXx;
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totalCount, int startIndex){ G6?+Qzr
setPageSize(PAGESIZE); 28N
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setTotalCount(totalCount); 3TS(il9A
setItems(items); "\]NOA*
setStartIndex(startIndex); y>DvD)
} 'Lb-+X,
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public PaginationSupport(List items, int OE4hGxG
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totalCount, int pageSize, int startIndex){ 7@@,4_q E
setPageSize(pageSize); l(CMP!mY
setTotalCount(totalCount); ;Uxr+,x~
setItems(items); ckWK+
setStartIndex(startIndex); yK #9)W-
} jhN]1t/\X
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publicList getItems(){ ~)k OOoH
return items; r- :u*
} 8LMO2Wyq
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publicvoid setItems(List items){ }{(dG7G+
this.items = items; 1oSrhUTy
} $%3"@$
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publicint getPageSize(){ DnZkZ;E/
return pageSize; s$,gM,|cK
} #J,?oe=<4
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publicvoid setPageSize(int pageSize){ *C*'J7
this.pageSize = pageSize; jM'kY|<g;
} c9 c_7g'q-
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publicint getTotalCount(){ TI9]v(
return totalCount; Hlr[x
} Id/-u[-yo
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publicvoid setTotalCount(int totalCount){ ky^p\dMh
if(totalCount > 0){ =@%Ukrd@
this.totalCount = totalCount; #Oeb3U
int count = totalCount / k[`9RGT
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pageSize; k\qF> =
if(totalCount % pageSize > 0) )M!6y%b67
count++; 007(k"=oV
indexes = newint[count]; 5a PPq~%
for(int i = 0; i < count; i++){ ~T{^7"q\
indexes = pageSize * ~'[0-_]=f
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i; [f?fA[,[
} X(`wj~45VX
}else{ r ^m8kYezQ
this.totalCount = 0; `k 5'nnyP
} J ^y1=PM
} IYo{eX~=
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publicint[] getIndexes(){ :?*|D p1
return indexes; gyt[ZN_2
} 0Q]ZS
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publicvoid setIndexes(int[] indexes){ |A'y|/)#Z
this.indexes = indexes; ~ryB*eZH
} j`'9;7h M6
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publicint getStartIndex(){ /.{q2]
return startIndex; Z/r =4
} u?J!3ZEtb
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publicvoid setStartIndex(int startIndex){ iE~][_%U
if(totalCount <= 0) jc4#k+sb
this.startIndex = 0;
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elseif(startIndex >= totalCount) wc%Wy|d
this.startIndex = indexes h2b,(
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[indexes.length - 1]; biBo?k;4
elseif(startIndex < 0) 8R) 0|v&;
this.startIndex = 0; j>{Dbl:#2
else{ R7q\^Yzo
this.startIndex = indexes
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[startIndex / pageSize]; e6
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} !>,\KxnM
} /f5*KRM
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publicint getNextIndex(){ t==CdCl
int nextIndex = getStartIndex() + "}ms|
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pageSize; rkF>c
if(nextIndex >= totalCount) y*BS
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return getStartIndex(); ?YeUA =[MC
else eWgqds
return nextIndex; GQ@`qYLZ+
} j.?c~Fh
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publicint getPreviousIndex(){ >{seaihK
int previousIndex = getStartIndex() - OzVCqq"]
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pageSize; {CO]wqEj
if(previousIndex < 0) iOFp 9i=j
return0; AqdQiZ^9
else z frEM
return previousIndex; L[|($vQ"
} P1r)n{;
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} B"@3Q av3
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抽象业务类 z154lY}K
java代码: Q1b<=,
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/** FyF./
* Created on 2005-7-12 yobcAV`
*/ Ug VLHwkvk
package com.javaeye.common.business; x%hV5KW
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import java.io.Serializable; )U?5O$M;lE
import java.util.List; -E$(<Pow~\
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import org.hibernate.Criteria; ?g6xy[
import org.hibernate.HibernateException; JB
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import org.hibernate.Session; /.1yxb#Z?,
import org.hibernate.criterion.DetachedCriteria; >!D^F]CH
import org.hibernate.criterion.Projections; SJ4+s4!l
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import ep$C
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org.springframework.orm.hibernate3.HibernateCallback; KBe\)Vs
import '{[n,xeR
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org.springframework.orm.hibernate3.support.HibernateDaoS .Wr%l$~
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upport; ]52.nxs~
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import com.javaeye.common.util.PaginationSupport; x$:P;#
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public abstract class AbstractManager extends g5YDRL!Wh
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HibernateDaoSupport { -lb,0
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privateboolean cacheQueries = false; YLx4qE
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privateString queryCacheRegion; |+aUy^
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publicvoid setCacheQueries(boolean 6XFLWN-)
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cacheQueries){ 6w"_sK?
this.cacheQueries = cacheQueries; SyB2A\A
} [J{M'+a
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publicvoid setQueryCacheRegion(String _, ki/7{
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queryCacheRegion){ FJ/c(K
this.queryCacheRegion = -PG81F&K
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queryCacheRegion; &tJ!cTA.-
} ;!C~_{/t
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publicvoid save(finalObject entity){ UGb<&)
getHibernateTemplate().save(entity); )Z"
} zUIh^hbFf
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publicvoid persist(finalObject entity){ 5Y3L
getHibernateTemplate().save(entity); l!d |luqbA
} &>xd6-
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publicvoid update(finalObject entity){ TpSv7k T]
getHibernateTemplate().update(entity); -r'/PbV0
} }3TTtd7
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publicvoid delete(finalObject entity){ V?zCON
getHibernateTemplate().delete(entity); T[L7-5U0
} I&Z4?K
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publicObject load(finalClass entity, -Gyj]v5y`c
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finalSerializable id){ YjR`}rdwo
return getHibernateTemplate().load Sc/\g
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(entity, id); ;k=&ZV
} c{,VU.5/
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publicObject get(finalClass entity, nn?h;KzB
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finalSerializable id){ %`# HGji)
return getHibernateTemplate().get ceUhCb
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(entity, id); l2*o@&.
} 'O+)[D
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publicList findAll(finalClass entity){ SqosJ}K
return getHibernateTemplate().find("from %S$+3q%F
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" + entity.getName()); v.q`1D1=t
} "T4buTXJ
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publicList findByNamedQuery(finalString J/(^Z?/~P!
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namedQuery){ n([9U0!gu
return getHibernateTemplate )s~szmJoVD
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().findByNamedQuery(namedQuery); E |K|AdL
} A0l-H/l7
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publicList findByNamedQuery(finalString query, 1KMSBLx
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finalObject parameter){ !XqU'xxC
return getHibernateTemplate b uu /Nz$
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().findByNamedQuery(query, parameter); N87)rhXSo,
} ;ipT0*Y
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publicList findByNamedQuery(finalString query, WZQ
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finalObject[] parameters){ >At* jg48
return getHibernateTemplate @d1YN]ede
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().findByNamedQuery(query, parameters); >|1$Pv?
} r?$V;Z
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publicList find(finalString query){ '5xvR G
return getHibernateTemplate().find t}wwRWo2?f
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(query); wsEOcaie
} Tv6HPD$[
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publicList find(finalString query, finalObject 2/>u8j
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parameter){ @QO^3%b8
return getHibernateTemplate().find hQ@E2 Xsv
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(query, parameter); oiTSpd-
} A:4?Jd>
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public PaginationSupport findPageByCriteria %5ovW<E:
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(final DetachedCriteria detachedCriteria){ cfC}"As
return findPageByCriteria V)Sw\tS6g
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); )&s9QBo{b
} 1'YUK"i
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public PaginationSupport findPageByCriteria X-y3CO:&@h
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(final DetachedCriteria detachedCriteria, finalint 2Bz\Tsp
@:Emmzucv|
startIndex){ t\XA
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return findPageByCriteria dJF3]h Y
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(detachedCriteria, PaginationSupport.PAGESIZE, QJF_ "
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startIndex); ,v#O{ma
} }B ?_>0
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public PaginationSupport findPageByCriteria `rest_vu
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(final DetachedCriteria detachedCriteria, finalint 'mTQ=1
):]5WHYg
pageSize, vyvb-oz;u
finalint startIndex){ ~5>k_\G8
return(PaginationSupport) D4O^5?F)|
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getHibernateTemplate().execute(new HibernateCallback(){ v|R#[vtFd
publicObject doInHibernate 8bdx$,$k
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(Session session)throws HibernateException { V<ii
Criteria criteria = ^6QzaC3
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detachedCriteria.getExecutableCriteria(session); ENy$sS6[D
int totalCount = ~X(2F#{<{
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((Integer) criteria.setProjection(Projections.rowCount ~5o2jTNy`p
zyB>peAp6j
()).uniqueResult()).intValue(); INEE
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criteria.setProjection M=54xTh0Y
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(null); FA{'Ki`
List items = meYGIP:n
}t*:EgfI
criteria.setFirstResult(startIndex).setMaxResults +GEdVB
X#o<))
(pageSize).list(); -_M':
PaginationSupport ps = 73l,PJ
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new PaginationSupport(items, totalCount, pageSize, Oe21noL
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startIndex); #y
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return ps; 84<zTmm
} aA]wFZ
}, true); :W#?U yo
} (QS 0
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public List findAllByCriteria(final r72zWpF!Ss
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DetachedCriteria detachedCriteria){ 1}~ZsrF
return(List) getHibernateTemplate oDWNOw
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().execute(new HibernateCallback(){ (6i4N2
publicObject doInHibernate 40O@a:q*
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(Session session)throws HibernateException { _BoA&Ism
Criteria criteria = ]:}7-;$V
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detachedCriteria.getExecutableCriteria(session); !ScEA=
return criteria.list(); p}e| E!
} a@-bw4SD
}, true); T^ - - :1
} ,<$rSvMfg
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public int getCountByCriteria(final 5cb8=W-
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DetachedCriteria detachedCriteria){ nG$+9}\UlP
Integer count = (Integer) ,/"0tP&_;
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getHibernateTemplate().execute(new HibernateCallback(){ Z=
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publicObject doInHibernate 3bT?4
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(Session session)throws HibernateException { [OS&eK 8
Criteria criteria = T%A"E,#
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detachedCriteria.getExecutableCriteria(session); OVE?;x>n/1
return rP#&WSLVj
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criteria.setProjection(Projections.rowCount %pLqX61t=
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()).uniqueResult(); Gr'|nR8
} PbfgWGr
}, true); U?ZWDr"*`w
return count.intValue(); kG5Uc83#G
} "-\8Y>E
} o wwWm1@
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用户在web层构造查询条件detachedCriteria,和可选的 :m36{#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >>cL"m
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PaginationSupport的实例ps。 )$K\:w>
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ps.getItems()得到已分页好的结果集 ZiRCiQ/?
ps.getIndexes()得到分页索引的数组 fu?u~QZ8
ps.getTotalCount()得到总结果数 ?J-D6;
ps.getStartIndex()当前分页索引 \YHl(
ps.getNextIndex()下一页索引 AW'$5NF>
ps.getPreviousIndex()上一页索引 Gzwb<e
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ce*?crOV
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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 `6BQ6)7
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一下代码重构了。 IJC]Al,df
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我把原本我的做法也提供出来供大家讨论吧: bP,Ka
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首先,为了实现分页查询,我封装了一个Page类: Asy2jw\V
java代码: PR*EyM[T
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/*Created on 2005-4-14*/ qIB2eCXw
package org.flyware.util.page; k=G c#SD5_
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/** x=X&b%09
* @author Joa fAfB.|cd
* 16Jjf|]j
*/ 5DO}&%.xt
publicclass Page { 0.c96&
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/** imply if the page has previous page */ C
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privateboolean hasPrePage; d,Oe3?][0p
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/** imply if the page has next page */ RRzLQ7J
privateboolean hasNextPage; *}_i[6_\E
rrq7UJ;
/** the number of every page */ \Ym!5,^o
privateint everyPage; r{_1M>F
D!
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/** the total page number */ !1@oZ(
privateint totalPage; ;Wsl 'e/
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/** the number of current page */ ymT]ow6C
privateint currentPage; .'4@Yp{=
A7eYKo
q
/** the begin index of the records by the current [?(qhp!
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query */ v&7x ~!O
privateint beginIndex; _d+` Gw
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/** The default constructor */ JeAyT48!M
public Page(){ SRU#Y8Xv|
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} z6h/C{
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/** construct the page by everyPage u'gsIuRJ
* @param everyPage 6UuM`eu
* */ QUF1_Sa
public Page(int everyPage){ " LhXR
this.everyPage = everyPage; |/Y!R>El
} }:1qK67S
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/** The whole constructor */ =/4}!B/
public Page(boolean hasPrePage, boolean hasNextPage, Tb*Q4:r"
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int everyPage, int totalPage, = N:5#A
int currentPage, int beginIndex){ . TNJuuO
this.hasPrePage = hasPrePage; Zc*#LsQh.`
this.hasNextPage = hasNextPage; pBn;:
this.everyPage = everyPage; P(3$XMx
this.totalPage = totalPage; n@S|^cH
this.currentPage = currentPage; ^,[gO#hgz
this.beginIndex = beginIndex; %WYveY
} A-eCc#I
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/** e'=#G$S?g
* @return `qZ@eGZ
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* Returns the beginIndex. Rn{X+b.
*/ Bu{%mm(
publicint getBeginIndex(){ RhE|0N=
return beginIndex; u
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} d ;,C[&
#jg3Ku;Y
/** -cUw}
* @param beginIndex t 1G2A`
* The beginIndex to set. #rp)Gc
*/ SK_N|X].
publicvoid setBeginIndex(int beginIndex){ 0,iG9D7
this.beginIndex = beginIndex; ?:F Jc[J
} SV^[)p)
P%<MQg|k`
/** Ac/LNqIs
* @return 1W9uWkk_d
* Returns the currentPage. HLh]*tQG
*/ '2{60t_A
publicint getCurrentPage(){ ntZHO}'
return currentPage; a!PN`N28
} } OkK@8?0O
/EL3Tt
/** ?Uhjyi
* @param currentPage 9v7}[`^
* The currentPage to set. >-(,BfZ
*/ 2F ~SH
publicvoid setCurrentPage(int currentPage){ ,rhNXx
this.currentPage = currentPage; :r&4/sN}<
} V<d`.9*}
'jKCAU5/0;
/** |;YDRI
* @return +V#dJ[,8;.
* Returns the everyPage. / 6DW+!
*/ %y)LBSxf
publicint getEveryPage(){ n5*m x7
return everyPage; B5]nP .R
} y"zZ9HQM
G52z5-=v
/** ]YB,K)WQ
* @param everyPage X\BdN Hr
* The everyPage to set. % "ZC9uq?
*/ zZ8:>2Ps(
publicvoid setEveryPage(int everyPage){ X
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this.everyPage = everyPage; 2JHV*/Q
} !'=<uU-
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/** >}86#^F
* @return Jz-RMX=
* Returns the hasNextPage. P>7PO~E.
*/ U^OR\=G^
publicboolean getHasNextPage(){ )N&95\u
return hasNextPage; -V||1@
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} s6I/%R3
) =|8%IrB
/** B>
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* @param hasNextPage kO,vHg$
* The hasNextPage to set. <ol?9tm
*/ +^%0/0e
publicvoid setHasNextPage(boolean hasNextPage){ XZ|\|(6Cc
this.hasNextPage = hasNextPage; {.r9l
} H8!lSRq
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/** Wk]E6yz6
* @return /? Bu^KX
* Returns the hasPrePage. uecjR8\e
*/ Z'c9xvy5
publicboolean getHasPrePage(){ @u8kNXT;h
return hasPrePage; %v]-:5g'|
} &lB>G[t
+ )7h)uq
/** F>5)Clq
* @param hasPrePage <ceJ!"L
* The hasPrePage to set. t;lK=m|
*/ 4n2*2
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publicvoid setHasPrePage(boolean hasPrePage){ A)kdY!}
this.hasPrePage = hasPrePage; g=S|lVQm
} prVqV-S6TY
;oRgg'k<
/** ABhQ7
x|
* @return Returns the totalPage. b yJ[1UK
* ,h.hgyt
*/ IVG77+O# }
publicint getTotalPage(){ vH]2t.\
return totalPage; [uu<aRAg3O
} zB+zw\ncN
@G=_nZxv
/** 49 1 1
* @param totalPage f7 zGz
* The totalPage to set. kfy|3KA3m
*/ 5+*CBG}
publicvoid setTotalPage(int totalPage){ sH Hu<[psM
this.totalPage = totalPage; vNAQ/Q
} MNKY J
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} R"e53 3
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s%)>O{{)
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n*N`].r#{=
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 d?=r:TBU
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个PageUtil,负责对Page对象进行构造: QeD ;GzG
java代码: ]U5/!e
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/*Created on 2005-4-14*/ l`*R !\
package org.flyware.util.page; R,W
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import org.apache.commons.logging.Log; hu-6V="^9
import org.apache.commons.logging.LogFactory; h)
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/** );V.le}%(
* @author Joa B%KfB
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* 4NmLbM&C8
*/ h7>`:~
publicclass PageUtil { ~01Fp;L/
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privatestaticfinal Log logger = LogFactory.getLog i8`0-
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(PageUtil.class); DX8pd5U
@%$<,$=
/** h, P#)^"
* Use the origin page to create a new page /1LQx>1d
* @param page UQ+!P<>w
* @param totalRecords zT jk^
* @return o$,e#q)8
*/ GhY MO6Q4
publicstatic Page createPage(Page page, int rFYw6&;vOi
R"[U<^
totalRecords){ [!b=A:@
return createPage(page.getEveryPage(), s;YuB#Z
v,,Dz8!Ty
page.getCurrentPage(), totalRecords); %weG}gCM
} RL1cx|
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/** Ea?u5$>gY"
* the basic page utils not including exception A$o ?_
&13#/
handler ,c[f/sT\
* @param everyPage :%"$8o*0W
* @param currentPage psE&Rx3)
* @param totalRecords !"N-To-c
* @return page UWq[K&vQZ
*/ k>7 2W/L^
publicstatic Page createPage(int everyPage, int hdx"/.s
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currentPage, int totalRecords){ PkxhR;4
everyPage = getEveryPage(everyPage); r
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currentPage = getCurrentPage(currentPage); x<[W9Z'~?9
int beginIndex = getBeginIndex(everyPage, Y%)@)$sK
[V.#w|n
currentPage); x8E!Ko](
int totalPage = getTotalPage(everyPage, ^Euqy,8}
zX ?@[OT
totalRecords); :/FT>UCL
boolean hasNextPage = hasNextPage(currentPage, ##qs{s^]
:<>=,`vQD
totalPage); ~>|o3&G{
boolean hasPrePage = hasPrePage(currentPage); TTzvH;S
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returnnew Page(hasPrePage, hasNextPage, j43-YdCJ
everyPage, totalPage, @j?)uJ0Q
currentPage, ,.&y-?
jsnk*>j
beginIndex); haIH `SY
} 1A-ess\
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privatestaticint getEveryPage(int everyPage){ \v[?4[
return everyPage == 0 ? 10 : everyPage; YVB\9{H?
} ld/\`s[i
UqaV9
privatestaticint getCurrentPage(int currentPage){ 7.`:Z_
return currentPage == 0 ? 1 : currentPage; a 9f%p
} }o MY
Q{+N{/tF
privatestaticint getBeginIndex(int everyPage, int IJV1=/NJW
'"14(BvW
currentPage){ lq\/E`fc`
return(currentPage - 1) * everyPage; b)Dzau
} 7>>6c7e
dUL3UY3
privatestaticint getTotalPage(int everyPage, int DZ~qk+,I
V50FX}i
totalRecords){ LHJjPf)F
int totalPage = 0; Z 361ko}
{%Q&CQG_
if(totalRecords % everyPage == 0) ;UG]ckV-
totalPage = totalRecords / everyPage; BX=YS)
else F~tT5?+
totalPage = totalRecords / everyPage + 1 ; SN/
e41
|]8Hh>
return totalPage; Y1Qg|U o
} 9py*gN#
*P}v82C N
privatestaticboolean hasPrePage(int currentPage){ V8{5 y
<Y>
return currentPage == 1 ? false : true; LU4k/
} }hd:avze
QvN=<V
privatestaticboolean hasNextPage(int currentPage, ?A7_&=J%
#^~[\8v>
int totalPage){ N++jI(
return currentPage == totalPage || totalPage == P(#by{s
7Ta",S@m
0 ? false : true; m?Qr)F_M
} 3>t^Xu~
ME%W,B.|"s
;.4A,7w#
} (( D*kd"
T,eP&IN
,3tcti~sZ
A$]&j5nh|
\$]
V#@F
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。 ow{Ss X
k{q4Zz[
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 <_~>YJ
o|?bvFC
做法如下: :L!O/Bd8V
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sHSD`mYq
8DsXw@o
的信息,和一个结果集List: _H+|Ic
java代码: $<(FZb=
#}Qzu~
mOkf
/*Created on 2005-6-13*/ SuU_psF
package com.adt.bo; zrg#BXj7
rL/e
import java.util.List; 8I`t`C/4
\Gk4J<
import org.flyware.util.page.Page; E8=8OX/{Y
u'BuZF
/** TsB"<6@!AA
* @author Joa "/&_B
*/ |*+f N8
publicclass Result { ZFAi 9M
,@1.&!F4it
private Page page; X <<hb
D<
h+r?
private List content; hS}d vZa
feH|sz`e
/** }Ra'`;D$
* The default constructor 1k
*gbXb
*/ Uz`K#Bz
public Result(){ DFKumw>!
super(); C Ahkv0?8
} Gw5j6
_*SA_.0
/** ymxYE#q
* The constructor using fields m.}Yn,
* 5g{F-
* @param page YGj3W.eH
* @param content Rt[zZv
*/ t'@qb~sf
public Result(Page page, List content){ !u0qF!/W
this.page = page; VQQtxHTC3
this.content = content; $]Vvu{
} 5zqlK-$
X(Wd
/** _rz*7-ks=
* @return Returns the content. ]}~[2k.
*/ H~IN<3ko
publicList getContent(){ =D2jJk?AX
return content; .9< i
} &F*L=Ng
%6vf~oG
/** wm$1LZ8o-`
* @return Returns the page. 8$H_:*A?
*/ d3$&I==;:
public Page getPage(){
YtzB/q8I
return page; ptrQ~m-
} 5jTBPct
K9#=@}!3L
/** ]+SVQ|v0
* @param content /=5YHq>
* The content to set. I'_u4
*/ \UdHN=A&
public void setContent(List content){ 'n9<z)/,!
this.content = content; a19yw]hF5
} Y 7a<3>
SOq{`~,4B
/** ~qG`~/7
* @param page uK:?6>H
* The page to set. =lzRx%tm
*/ TfD]`v`]
publicvoid setPage(Page page){ ndIf1}
this.page = page; 3 9|4)1e
} vakAl;
} $\0%"S
SA| AS<
N6"b
OxJ(
f
xWW"B*A
CMm:Vea
2. 编写业务逻辑接口,并实现它(UserManager, kIb)I(n
8Rgvb3u
UserManagerImpl) z"b}V01F#
java代码: oA^aT:o +
SIBNU3;DL
bOt6q/f
/*Created on 2005-7-15*/ 7gL N7_2
package com.adt.service; :
"|M
V'XmMn)!
import net.sf.hibernate.HibernateException; y|BRAk&n
8E m X
import org.flyware.util.page.Page; "Dc6kn^}3
zHI_U\"8D
import com.adt.bo.Result; =@ '>|-w|
X*'tJN$
/** E|(T(4;
* @author Joa s&<6{AU(id
*/ 3HU_~%l
publicinterface UserManager { U4J9bp|
|mSF a8G@
public Result listUser(Page page)throws /kl41gx
h}X^
HibernateException; ? 1OZEzA!
/B$9B
} 03F%!Rm/j
"k)}qI{
Osb#<9{}
=*VKp{5=
p[Pa(a,B7
java代码: {bxTODt@
}klET
J YA
/*Created on 2005-7-15*/ )T-C/ 3
package com.adt.service.impl; He#5d!cf:M
xz-z"
8d
import java.util.List; uQwKnD?F+e
0Q81$% @<
import net.sf.hibernate.HibernateException; XYJ7k7zc+Y
wA+QUN3#n
import org.flyware.util.page.Page; 39xA h*}G]
import org.flyware.util.page.PageUtil; )ZU)$dJ>V
K3uNR w
import com.adt.bo.Result; %h)6o99{wF
import com.adt.dao.UserDAO; <oweLRt
import com.adt.exception.ObjectNotFoundException; d|^cKLu
import com.adt.service.UserManager; uSeRn@
h]wahExYP
/** ]SqLF!S(=
* @author Joa {XT3M{`rWL
*/ &n_aMZ;
publicclass UserManagerImpl implements UserManager { -^C't_Q o
njbEw4nX
private UserDAO userDAO; hJrcy!P<a
B0_[bQoc1
/** %^e~;i=2
* @param userDAO The userDAO to set. [0M2`x4`
*/ 4fK(<2i
publicvoid setUserDAO(UserDAO userDAO){ Q}pnb3J>T
this.userDAO = userDAO; ' }G!D
} W'3&\}
[I4:R_\
/* (non-Javadoc) [(Z sQK
* @see com.adt.service.UserManager#listUser T=/GFg'
qb^jcy
(org.flyware.util.page.Page) ]g#ur@Y%
*/ |'w_5?|4
public Result listUser(Page page)throws K4]42#
Rgb1B3gu
HibernateException, ObjectNotFoundException { {`2R<O
int totalRecords = userDAO.getUserCount(); Y<~Nx~w{
if(totalRecords == 0) X6+2~'*t
throw new ObjectNotFoundException I%.96V
~hubh!d=
("userNotExist"); OQ[E-%v1 R
page = PageUtil.createPage(page, totalRecords); t7A '
List users = userDAO.getUserByPage(page); 3~zK :(
returnnew Result(page, users); ~]+-<O^U~
} }LXS!Ff:
3=6`'PKRQ
} I)
mP?
ds@w=~
tCT-cs
Oeua<,]Z~
ttEQgkd`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 KmuE#Ia
G8c 8`~t
询,接下来编写UserDAO的代码: 6XVr-ef
3. UserDAO 和 UserDAOImpl: 4nC`DJ;V
java代码: kbqG)
4vri=P 2%
k=t\
/*Created on 2005-7-15*/ +f{CfWIKs
package com.adt.dao; O]ZP- WG
qT`sPEs;V
import java.util.List; W$&kOdD!$
;aZ$qgN*Y
import org.flyware.util.page.Page; 6pkZ8Vp:
it=4cHT
import net.sf.hibernate.HibernateException; b;wf7~a*
"AN2K
/** %GRD3S
* @author Joa | aH;@V
*/ j@4
yRl ^
publicinterface UserDAO extends BaseDAO { ]Y#$!fIx
Ri$wt.b
publicList getUserByName(String name)throws Qo*,2B9R L
BMw_F)hTO
HibernateException; sE*A,z?
ENlqoj1
publicint getUserCount()throws HibernateException; PJC[#>}
!Vtt.j &4
publicList getUserByPage(Page page)throws "NU l7ce.R
f/spJ<B).4
HibernateException; [Z2:3*5r.
/*5t@_0fe
} t;P%&:"@M
DNsDEU
4"$K66yk@
>KjyxJ7
%
K$om|]p
java代码: %9z N U
t`b>iX%(1t
->DfT*)
/*Created on 2005-7-15*/ IUX~dO
package com.adt.dao.impl; Vp =
1}#(4tw)
import java.util.List; >>lT-w
hg}Rh
import org.flyware.util.page.Page;
:e-&,K
EleK*l
import net.sf.hibernate.HibernateException; <ex,@{n4
import net.sf.hibernate.Query; 1:-^*
__U;fH{c
import com.adt.dao.UserDAO; F$kLft[:
TGnyN'P|
/** s>Eu[uA
* @author Joa M8Y\1#~
*/ m5HP56a
public class UserDAOImpl extends BaseDAOHibernateImpl EjsAV F
[@
jEQr{X7bEL
implements UserDAO { x`'2oz=,F4
pWo`iM& F
/* (non-Javadoc) 5t6!K?}
* @see com.adt.dao.UserDAO#getUserByName ei 1(A
()=u#y
(java.lang.String) 0sjw`<ic
*/ zV)Ob0M7U
publicList getUserByName(String name)throws m?;aTSa
po~l8p>
HibernateException { +MG(YP/l
String querySentence = "FROM user in class ZyE2=w7n
K*uFqdLL!
com.adt.po.User WHERE user.name=:name"; k0|*8
Query query = getSession().createQuery h:QKd!Gq
*uYnu|UQH
(querySentence); q2VQS1R`8
query.setParameter("name", name); 'jp nQcwxx
return query.list(); w$J0/eX{A
} 8fpaY{]
Xrnxpp!#^D
/* (non-Javadoc) iE}jilU
* @see com.adt.dao.UserDAO#getUserCount() S[fzy$">
*/ `r"euO
r\
publicint getUserCount()throws HibernateException { uHdrHP
int count = 0; E.v~<[g
String querySentence = "SELECT count(*) FROM s&S8P;K|
l" y==y
user in class com.adt.po.User"; AL/`Pqlk
Query query = getSession().createQuery 1nh2()QI[
HjTK/x'_'L
(querySentence); /kL X
f_
count = ((Integer)query.iterate().next n8"S;:Zm
Ba/Z<1)
()).intValue(); H27J kZ&
return count; zuOx@T^
} ?' H);ou-p
/kGRN@
/* (non-Javadoc) pyK|zvr-r
* @see com.adt.dao.UserDAO#getUserByPage M70X dn
A:3bL:
;t
(org.flyware.util.page.Page) VNx|nP&
*/ 8ID
fYJ
publicList getUserByPage(Page page)throws 0*^)n&O
SJ1
1LF3)
HibernateException { i70TJk$fs
String querySentence = "FROM user in class gvYib`#
{t: ZMUV
com.adt.po.User"; C)>
])'S
Query query = getSession().createQuery gBRhO^Sz
)f4D2c&VE
(querySentence); {N+N4*
query.setFirstResult(page.getBeginIndex()) Vm]ltiTVk
.setMaxResults(page.getEveryPage()); P>%\pCJ])
return query.list(); S5ka;g
} Xz5 aTJ&
gP.Q_/V
} uV<I!jyI
2U,O
e9
G.K3'^_
<Gzy*1Q&
m`UNdFS
至此,一个完整的分页程序完成。前台的只需要调用 Z~o*$tF/
)AOD~T4s7
userManager.listUser(page)即可得到一个Page对象和结果集对象 !Y_"q^5GG'
iK%<0m
的综合体,而传入的参数page对象则可以由前台传入,如果用 tx;DMxN!W
Q[i/]
webwork,甚至可以直接在配置文件中指定。 ug!DL=ZW
JsOPI]
下面给出一个webwork调用示例: X ^>o/U
java代码: oo7&.HWf
XJnDx 09h
2A@9jl s
/*Created on 2005-6-17*/ {O*<1v9<
package com.adt.action.user; *zX*k7LnV
D"fE )@Q@Y
import java.util.List; WlP#L`
MP, l*wVd
import org.apache.commons.logging.Log; rAD5n,M]
import org.apache.commons.logging.LogFactory; QLo^6S5!
import org.flyware.util.page.Page; yv4ki5u`
+]Of f^s
import com.adt.bo.Result; ]B0>r^
import com.adt.service.UserService; FQ?,&s$Bmd
import com.opensymphony.xwork.Action; j[YzBXd
V
Kg&{
?&
/** y|b|_eE?{
* @author Joa B+|E|8"
*/ p8y_uNQE
publicclass ListUser implementsAction{ /zn|?Y[
PPT"?lt*&
privatestaticfinal Log logger = LogFactory.getLog )NZ6!3[@
%>'2E!%
(ListUser.class); >L/Rf8j &
!o &+
private UserService userService; k%#`{#ni
VtF^;
f
private Page page; }(O/ y-
!_s|h@
privateList users; hNUAwTH6
^[XxE Lx
/* 5gW`;Cdbyc
* (non-Javadoc) hb9X<N+p
* u814ZN}
* @see com.opensymphony.xwork.Action#execute() %*P59%
*/ o#E 3{zM
publicString execute()throwsException{ mnL
\c'
Result result = userService.listUser(page); 1Nx.aji
page = result.getPage(); S{j|("W"[
users = result.getContent(); a>`\^>G4
return SUCCESS; [8.ufpZ
} "|`8mNC
K|];fd U
/** {
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* @return Returns the page. .Ozfj@ f
*/ gs 8w/
public Page getPage(){ rq9{m(
return page; vJ>A
>RCB
} noe1*2*T E
}GsZ)\!$4
/** >b,o yM
* @return Returns the users. gBHev1^y
*/ xBU\$ToC
publicList getUsers(){ ;OmmXygl
return users; Jl&bWp^3
} j11 \t
,Ihuo5>/z
/** [6BLC{2
* @param page NKLGbH
* The page to set. 8-cG[/|0
*/ sl|s#+Z
publicvoid setPage(Page page){ _3tHzDSG#
this.page = page; 8,YF>O&
} ]R}#3(]1
Ri4_zb
/** UT [7 J
* @param users m\7-/e2a
* The users to set. <1&kCfE&
*/ ~X5yHf3
publicvoid setUsers(List users){ +,7dj:0S
this.users = users; c a_N76o!
} #`:s:bwM:
2ko7t9y&
/** tu77Sb
* @param userService
\8Mkb]QA
* The userService to set. x@2rfs
*/ ?1 r@r
publicvoid setUserService(UserService userService){ 7GfgW02
this.userService = userService;
wxsJB2
} qyUcjc%[
} p*!@z|F>U
YS?P A#
NmST1pMk
M
^ZoBsZ
Y_>z"T
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, BzF.KCScs
51.F,uY
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 v6oPAqj,r
riZFcVsB
么只需要: G6JyAC9j
java代码: Q6,rY(b6
3k;U#H
vi4 1`
<?xml version="1.0"?> -6~*:zg,
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Sn.I
]:l
seHwn'Jn
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 7t5X
7oF`Os+U
1.0.dtd"> oF.Fg<p(
2P$l XGjh
<xwork> 5YC56,X
I.R3?+tZ
<package name="user" extends="webwork- 'nP'MA9b;a
^K@r!)We
interceptors"> 6\ux;lksn*
Z/q%%(fh 0
<!-- The default interceptor stack name >1pD'UZIy7
?*}76u
--> *IGxa
<default-interceptor-ref =d~]*[8
ifTVTd7O
name="myDefaultWebStack"/> |rdG+>
c/;t.+g
<action name="listUser" Lj *FKP\{
ol!o8M%Q
class="com.adt.action.user.ListUser"> :m8ED[9b
<param ||`w MWq
><LIOFqsS
name="page.everyPage">10</param> H!F'I)1
<result )FWF T:P~
>]:R{1h
name="success">/user/user_list.jsp</result> t8i"f L
</action> XYod>[.x
l]WV?^*
</package> (n" )
P7egT,Z
</xwork> n,PHfydqX
zmr=iK
^+`vh0TPQ
t)cG_+rJ
G]P4[#5
:U)e
8
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 %T'?7^\>
4Xz6JJ1U[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。 ~lDLdUs
H7Y}qP5X
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 C| Mh<,~E
+V2a|uvEc
rA`zuYo
#cdLg-v
d.2b7q09
我写的一个用于分页的类,用了泛型了,hoho )V@qH]
Ub3,x~V
java代码: W**=X\"'
.kC}. Q_
H kg@M?(
package com.intokr.util; *}/xy
SH3
&51/Pm2O
import java.util.List; l06 q1M 3
`t6lnO
/** 44%H? ,d
* 用于分页的类<br> "VT5WFj
* 可以用于传递查询的结果也可以用于传送查询的参数<br> P* aD2("Z
* H~ks"D1
* @version 0.01 M<ad>M
* @author cheng l$zNsf.
*/ ,1~Zqprn
public class Paginator<E> { ++dV5
privateint count = 0; // 总记录数 5@0c@Q
privateint p = 1; // 页编号 uFok'3!g7%
privateint num = 20; // 每页的记录数 2~ 'Q#(
privateList<E> results = null; // 结果 #m$H'O[WG\
xje{kx#
/** 2Cr+Z(f
* 结果总数 W!X#:UM)
*/ cU{LyZp
publicint getCount(){ nn=JM7e\9
return count; 1Rczf (,aT
} =x7ODBYW^
Ev^Xs6 }"
publicvoid setCount(int count){ dHp6G^Y
this.count = count; L1F){8[
} vo::y"
ADR`j;2
/** [")0{LSA=
* 本结果所在的页码,从1开始 l w%fY{
* c<H4rB
* @return Returns the pageNo. 3zl!x
*/ _p_F v>>:
publicint getP(){ 3/ [=
return p; EXBfzK)a
} vaQ,l6z
.h
M}nalr+#
/** +?.,pq n<=
* if(p<=0) p=1 F;b|A`M
* mdZELRu
* @param p TuF:m"4
*/ B"qG-ci
publicvoid setP(int p){ 5=?&q 'i
if(p <= 0) xS(sR x+A
p = 1; TWs|lhC7!
this.p = p; :w];N|48s
} kqyMrZ#
t
=*K?'ly
/** c^bA]l^a
* 每页记录数量 8odVdivh
*/ HhpP}9P;
publicint getNum(){ @i`gR%
return num; K&X'^|en
} )T4L^^`
`773& \PK
/** lyi}q"Kn*;
* if(num<1) num=1 !e7vc[N
*/ )a}5\V
publicvoid setNum(int num){ )F~_KD)7jJ
if(num < 1) |.S;z"v![
num = 1; [%@zH
this.num = num; cr/|dc'
} D3K`b4YV
?k3b\E3
/** x$Dv&4
* 获得总页数 <G&v
*/ _4W#6!
publicint getPageNum(){ srSTQ\l4
return(count - 1) / num + 1; B@=Yj_s
} O<E0L&4-&
x)?\g{JH
/** ms{R|vU%b
* 获得本页的开始编号,为 (p-1)*num+1 oF>GWstTR
*/ \8$`:3,@
publicint getStart(){ OM.^>=
return(p - 1) * num + 1; M ?3N
} D!P?sq _5r
XMdc n,
/** wiGwN
* @return Returns the results. I,S'zHR
*/ dL\8^L
publicList<E> getResults(){ Ax%BnkU
return results; L,ra=SV F
} =I5XG"",
N\fT6#5B
public void setResults(List<E> results){ nZT@d;]U9
this.results = results; |-mazvA
} `u}x:f !
#.><A8J
public String toString(){ t#q>U%!
StringBuilder buff = new StringBuilder Ocb2XEF
"h2Ny#
(); IF:M_
buff.append("{"); 6Te}"t>
buff.append("count:").append(count); m7"f6zSo(
buff.append(",p:").append(p); d"78:+
buff.append(",nump:").append(num); 47 RY pd
buff.append(",results:").append q>[% C5
W<4\4
(results); 42u\Y_^ID
buff.append("}"); ./
:86@O
return buff.toString(); KRtu@;?
} 93J)9T
Cm4*sN.&)
} A1q^E(}O
P&GZe/6Y
R\}YD*