Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 L"Qh_+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fF8a 1XV
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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 DBqg_v
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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 +Q@/F~1@6@
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。 3bT6W,J4T
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分页支持类:
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java代码: 3K=q)|
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package com.javaeye.common.util; G\'u~B/w
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import java.util.List; KdBq@
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publicclass PaginationSupport { WHpUjyBP
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publicfinalstaticint PAGESIZE = 30; s=\LewF1<
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privateint pageSize = PAGESIZE; iylBK!ou
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privateList items; :Y}Y&mA4
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privateint totalCount; +
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privateint[] indexes = newint[0]; !I~C\$^U
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privateint startIndex = 0; &;~2sEo,
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public PaginationSupport(List items, int w(vE2Y ?
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totalCount){ ex@,F,u>o
setPageSize(PAGESIZE); A4 A6F<
setTotalCount(totalCount); KG4#BY&^
setItems(items); "2#-xOCO
setStartIndex(0); pr[B$X.V
} 1Rb XM n
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public PaginationSupport(List items, int (^s &M
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totalCount, int startIndex){ aUIc=Z
setPageSize(PAGESIZE); N SxPN:
setTotalCount(totalCount); OUIUgej
setItems(items); 4mM2C`I
setStartIndex(startIndex); HP4'8#3o
} 90y9~.v
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public PaginationSupport(List items, int R[>;_}5">
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totalCount, int pageSize, int startIndex){ :EQme0OW
setPageSize(pageSize); aCYm$6LmA
setTotalCount(totalCount); 8}pcanPg
setItems(items); +GYI2
setStartIndex(startIndex); Rvu3Qo+
} @F3-Ugm
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publicList getItems(){ Ip7FD9
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return items; qm'C^X?
} >Xh(`^}SQ*
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publicvoid setItems(List items){ m`yn9(1Y[
this.items = items; 0r$hPmvv8
} YPff)0Nh
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publicint getPageSize(){ R26tQbwE
return pageSize; nnd-pf-
} }N#>q.M
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publicvoid setPageSize(int pageSize){ NW4
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this.pageSize = pageSize; d*\C^:Z
} Nh\8+v*+{
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publicint getTotalCount(){ A_(+r
return totalCount; >NOYa3
} #G!Adj+p5
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publicvoid setTotalCount(int totalCount){ j]?0}Z*
if(totalCount > 0){ 't]EkH]BC
this.totalCount = totalCount; J_wz'eIb0
int count = totalCount / 'G3OZj8
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pageSize; b%!`fn-;
if(totalCount % pageSize > 0) rIFC#Jd/
count++; P7x?!71?L
indexes = newint[count]; qnfRN'
for(int i = 0; i < count; i++){ i{FC1tVeL_
indexes = pageSize * ge
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} 4tTZkJc
}else{ -L 'K
this.totalCount = 0; 8(_g] u#B;
} O+o%C*`K
} e"adkV
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publicint[] getIndexes(){ 5 EuJ
return indexes; F+$@3[Q`N
} F.
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publicvoid setIndexes(int[] indexes){ y yR8VO{
this.indexes = indexes; s=~7m.m
} }NBJ T4R
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publicint getStartIndex(){ P_lcX;O
return startIndex; K<w5[E9V.
} 8(f0|@x^
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publicvoid setStartIndex(int startIndex){ <$ZT]p T
if(totalCount <= 0) pH:|G
this.startIndex = 0; P_g0G#`4
elseif(startIndex >= totalCount) y{?jr$js<
this.startIndex = indexes UO!6&k>c
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[indexes.length - 1]; %+!9
elseif(startIndex < 0) '*ICGKoT
this.startIndex = 0; J o(}#_y?
else{ =+=|{l?F
this.startIndex = indexes D&m"~wI
Lm{ o=v
[startIndex / pageSize]; yaXa8v'oC
} :*+BBC
} rtF6Lg
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publicint getNextIndex(){ molowPI
int nextIndex = getStartIndex() + d lLk4a+
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pageSize; 5XUI7Q%
if(nextIndex >= totalCount) >T^v4A
return getStartIndex(); KdpJ[[Ug/
else 9qy 9
return nextIndex; +<WT$ddK=5
} nJ})6/gK
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publicint getPreviousIndex(){ QGj5\{E_
int previousIndex = getStartIndex() - 4H=sD
t
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pageSize; y"-{6{3
if(previousIndex < 0) lFV|GJ
return0; FEmlC,%
else p%
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return previousIndex; 3i}B\
{
} [:S F(*}
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} q.F1Jj
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抽象业务类 bd*(]S9d
java代码: be#"517
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/** \^LR5S&
* Created on 2005-7-12 cGp 6yf
*/ Q^w]Nj(e_
package com.javaeye.common.business; S
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import java.io.Serializable; c6)zx
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import java.util.List; CW YJ<27v{
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import org.hibernate.Criteria; yuX0Y{:I
import org.hibernate.HibernateException; |YFlJ2w
import org.hibernate.Session; Sd6^%YB
import org.hibernate.criterion.DetachedCriteria; C8q-gP[
import org.hibernate.criterion.Projections; #8OqX*/
import )ix E
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org.springframework.orm.hibernate3.HibernateCallback; ,jcp"-5#j
import RR=l&uT
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org.springframework.orm.hibernate3.support.HibernateDaoS =oDrN7`,B
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upport; +]vl8, 4@
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import com.javaeye.common.util.PaginationSupport; P[i/o#
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public abstract class AbstractManager extends ]NsaFDi\
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HibernateDaoSupport { l}/UriZ0
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privateboolean cacheQueries = false; M-|2W~YU
) &-E@% \
privateString queryCacheRegion; \_bX2Lg
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publicvoid setCacheQueries(boolean Z4' v
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cacheQueries){ "O
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this.cacheQueries = cacheQueries; LL+rdxJO^
} Cx~z^YP'
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publicvoid setQueryCacheRegion(String 9k&$bC+Q
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queryCacheRegion){ :Ej)AfS
this.queryCacheRegion = ERjf.7)d
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queryCacheRegion; \gpKQt0
} rC16?RovQ@
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publicvoid save(finalObject entity){ n0q(EQy1U
getHibernateTemplate().save(entity); N0PX<$y
} C@i g3fhV
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publicvoid persist(finalObject entity){ v%^H9aK_
getHibernateTemplate().save(entity); mgWtjV 8
} qFk(UazN
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publicvoid update(finalObject entity){ .O^|MhBJu
getHibernateTemplate().update(entity); A )cb
} \
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publicvoid delete(finalObject entity){ Kw|`y %~
getHibernateTemplate().delete(entity); ;r']"JmF,
} ZHJzh\?
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publicObject load(finalClass entity, I_rVeMw=
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finalSerializable id){ {ex]_V>
return getHibernateTemplate().load j>iM(8`t1
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(entity, id); 5`Bb0=j
} Ih0GzyU*4
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publicObject get(finalClass entity, "x11 YM{F
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finalSerializable id){ r[x7?cXsW
return getHibernateTemplate().get ^BZdR<;
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(entity, id); 4/4IZfznX
} uRIr,U^
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publicList findAll(finalClass entity){ +j,;g#d
return getHibernateTemplate().find("from fu/c)D6u*m
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" + entity.getName()); RjT[y: !
} 2-4%h!
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publicList findByNamedQuery(finalString kL-+V)Kl
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namedQuery){ rZEu@63
return getHibernateTemplate 19S,>
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().findByNamedQuery(namedQuery); ;3!TOY"j;e
} 5>HI/QG
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publicList findByNamedQuery(finalString query, ktCh*R[`
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finalObject parameter){ 4{Iz\:G:{/
return getHibernateTemplate }7V/(K
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().findByNamedQuery(query, parameter); _heQ|'(
} KH;e)91
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publicList findByNamedQuery(finalString query, `{ /tx!
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finalObject[] parameters){ d+(~{xK:
return getHibernateTemplate |
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().findByNamedQuery(query, parameters); W `Soa&9
} gC 4w&yL
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publicList find(finalString query){ h3:k$`_
return getHibernateTemplate().find aU3&=aN+
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(query); u^ T2
} 7(jt:V6V
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publicList find(finalString query, finalObject yY1&hop
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parameter){ lY~xoHT;[
return getHibernateTemplate().find mBNa;6w?{*
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(query, parameter); W?$
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} {PfE7KH
{ "/@,!9rJ
public PaginationSupport findPageByCriteria B *:6U+I
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(final DetachedCriteria detachedCriteria){ p~r +2(J
return findPageByCriteria M?_VYK
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); )wKuumet
} _+UD>u{
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public PaginationSupport findPageByCriteria XpM#0hm
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(final DetachedCriteria detachedCriteria, finalint ?-(E$ll
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startIndex){ I3SLR
return findPageByCriteria a/?gp>M9
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(detachedCriteria, PaginationSupport.PAGESIZE, 'j}%ec1
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startIndex); \
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} vXyaOZ
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public PaginationSupport findPageByCriteria }lWEbQ)(!
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(final DetachedCriteria detachedCriteria, finalint ^oA^z1>3
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pageSize, +lE 9*Gs_$
finalint startIndex){ Ua(!:5q?
return(PaginationSupport) pTcm2-J
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getHibernateTemplate().execute(new HibernateCallback(){ N2C^'dFj
publicObject doInHibernate +HNQ2YZ
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(Session session)throws HibernateException { r]2}S=[
Criteria criteria = QarA.Ne~
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detachedCriteria.getExecutableCriteria(session); z )k\p'0"
int totalCount = H+-9R
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((Integer) criteria.setProjection(Projections.rowCount 7ej"q
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()).uniqueResult()).intValue(); Xa+ u>1"2"
criteria.setProjection <1V!-D4xu
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(null); jiz"`,-},O
List items = A"p7N?|%
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criteria.setFirstResult(startIndex).setMaxResults ]{Iy<
2,'m]`;GNr
(pageSize).list(); `2Vc*R
PaginationSupport ps = <T<?7SE+
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new PaginationSupport(items, totalCount, pageSize, ,+%$vV
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startIndex); \,lgv
return ps; ABB4(_3E
} ]uj6-0q){W
}, true); !3}vl
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} 79=w]y
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public List findAllByCriteria(final r@^h,
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DetachedCriteria detachedCriteria){ M+9G^o)u
return(List) getHibernateTemplate 5&\Q0SX(~
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().execute(new HibernateCallback(){ O8r9&Nv
publicObject doInHibernate S2h?Q$e3
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(Session session)throws HibernateException { TnCN2#BO
Criteria criteria = ?,O{,2}
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detachedCriteria.getExecutableCriteria(session); &%$r3ePwc
return criteria.list(); 0sLR5A
} e@F9'z4
}, true); Ir }r98lz
} z;x$tO
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public int getCountByCriteria(final ;3-5U&Axt
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DetachedCriteria detachedCriteria){ ]2+7?QL,
Integer count = (Integer) S9U,so?
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getHibernateTemplate().execute(new HibernateCallback(){ CfNHv-jDL
publicObject doInHibernate 2xN1=ug
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(Session session)throws HibernateException { !U/iY%NE
Criteria criteria = a2 e-Q({
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detachedCriteria.getExecutableCriteria(session); 3.Oc8(N^}
return za`
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criteria.setProjection(Projections.rowCount !ZPaU11
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()).uniqueResult(); I9-vV>:z
} bwR24>8lP
}, true); VImcW;Xa
return count.intValue(); . T6fPEb
} Iww.Nd2
} '8R5?9"
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用户在web层构造查询条件detachedCriteria,和可选的 :Y`cgi0vkd
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 RsIR}.*
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PaginationSupport的实例ps。 r<,W{Va
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ps.getItems()得到已分页好的结果集 ~( 54-9&
ps.getIndexes()得到分页索引的数组 >bWx!M]
ps.getTotalCount()得到总结果数 }>Gnpc
ps.getStartIndex()当前分页索引 AQ:cim`
ps.getNextIndex()下一页索引 u4*7n-(
ps.getPreviousIndex()上一页索引 ;$gZ?&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 H-$ )@
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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 !mLQdkTE
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一下代码重构了。 gU1E6V-Jm
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我把原本我的做法也提供出来供大家讨论吧: \W$bOp
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首先,为了实现分页查询,我封装了一个Page类: Rd7[e^HSN
java代码: 7DaMuh~<
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/*Created on 2005-4-14*/ LnZzY0
package org.flyware.util.page; P[{qp8(g
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/** l`D^)~o8
* @author Joa E=!=4"rZF
* <j" }EEb^
*/ :l<)p;\
publicclass Page { ? ->:,I=<~
8l,`~jvU!*
/** imply if the page has previous page */ H>Wi(L7
privateboolean hasPrePage; o|#Mq"od
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/** imply if the page has next page */ MJJ]8:%
privateboolean hasNextPage; m>dZ n
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/** the number of every page */ 5c50F{
privateint everyPage; <s/n8#i=H
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/** the total page number */ Exir?G} \
privateint totalPage; lR]z8&
Fe8JsB-
/** the number of current page */ a#H2H`%
privateint currentPage; 8vFt<k}G
=@%;6`AVcp
/** the begin index of the records by the current 1~BDtHW7`n
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query */ *Z0 Y:"
privateint beginIndex; 0Y rdu,c
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/** The default constructor */ h{zE;!+)D
public Page(){ D(3\m)
fQ>=\*b9x^
} |,zcrOo]
>:W7f2%8`
/** construct the page by everyPage Hx;ij?
* @param everyPage I5RV:e5b
* */ DG_tmDT4
public Page(int everyPage){ Wxjv=#3
this.everyPage = everyPage; 3{e7j6u\
} rBBA`Ut@F
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/** The whole constructor */ (hywT)#+
public Page(boolean hasPrePage, boolean hasNextPage, vCC}IDd
)
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int everyPage, int totalPage, Fy4jujP<
int currentPage, int beginIndex){ x;H#-^LxW=
this.hasPrePage = hasPrePage; 5`:+NwXS2
this.hasNextPage = hasNextPage; %9.]
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this.everyPage = everyPage; XD\RD
this.totalPage = totalPage; m9*Lo[EXO
this.currentPage = currentPage; ZLA&<]Ad"$
this.beginIndex = beginIndex; .H1kl)~V
} cv fh:~L
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/** M1._{Jw5
* @return n^QOGT.s6`
* Returns the beginIndex. $YDZtS&h
*/ p%304oP6
publicint getBeginIndex(){ 7?6?`no~JJ
return beginIndex; Mwdh]I,#
} yQwj[
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/** OCy\aCp
* @param beginIndex >V~q`htth
* The beginIndex to set. G?-27Jk8
*/ f_1#>]
publicvoid setBeginIndex(int beginIndex){ &fBLPF% 6
this.beginIndex = beginIndex; .8is!TT
} yjvH)t/!.
#8;|_RU
/** s{q)m@
* @return E-,74B&H
* Returns the currentPage. H~-zq}4
*/ I`h9P2~
publicint getCurrentPage(){ x&3!z[m@@
return currentPage; mi|O)6>8n
} ]UnZc
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/** /'1UfjW>
* @param currentPage lo:]r.lX{
* The currentPage to set. HMNjQ
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*/ k/nOz*
publicvoid setCurrentPage(int currentPage){ Egt;Bj#%
this.currentPage = currentPage; sm}q&m]ad
} 6w K=
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/** U{D ?1tF
* @return [!{*)4$6
* Returns the everyPage. BQf}S
+
*/ )8oI
s
publicint getEveryPage(){ !TY4C`/
return everyPage; 0CY_nn#3
} zQxZR}'
Y',s|M1})\
/** +SM $#
* @param everyPage 3y> .1
* The everyPage to set. mLD0Lu_Ob3
*/ ;9c3IK@
publicvoid setEveryPage(int everyPage){ ?)Lktn9%
this.everyPage = everyPage; AW6]S*rh
} W<;i~W
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/** 6KhHS@Z
* @return D`e!CprF
* Returns the hasNextPage. }.gDaxj
*/ G5zZf~r
publicboolean getHasNextPage(){ D>c%5h
return hasNextPage; qsFA~{o.
} (|ga#%iI
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/** >U"f1q*$
* @param hasNextPage X=(8t2
* The hasNextPage to set. FHM^x2
*/ \WouTn
publicvoid setHasNextPage(boolean hasNextPage){ H1|X0a(j
this.hasNextPage = hasNextPage; s;}';#
} u 8U>R=M
\ ;Hj,z\
/** -+|0LXo
* @return S=[K/Kf-
* Returns the hasPrePage. NNutpA}s
*/ D.qbzJz
publicboolean getHasPrePage(){ t> &$_CSWK
return hasPrePage; &Z=}H0y
q
} 2K,
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E( 8!VY ^
/** |\?-k
* @param hasPrePage k4pvp5}%
* The hasPrePage to set. ,Q(n(m'
*/ z2!NBOv
publicvoid setHasPrePage(boolean hasPrePage){ M0c"wi@S_
this.hasPrePage = hasPrePage; XpOsnvW
} .eZ4?|at.F
*KxV;H8/
/** ; {I{X}b
* @return Returns the totalPage. 1ErH \!
* 2c0eh-Gf
*/ ,PRM(n -
publicint getTotalPage(){ CNbrXN
return totalPage; pl fz)x3
} K*
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/** xZ`t~4qR
* @param totalPage c)@M7UK[
* The totalPage to set. ,dBtj8=
*/ _z,/!>J
publicvoid setTotalPage(int totalPage){ o>U%3-+T^J
this.totalPage = totalPage; ]3
0
7.
} MB^b)\X
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} \iowAo$
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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 +/Y)s5@<
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个PageUtil,负责对Page对象进行构造: (CZRX9TT1
java代码: /"iYEr%_
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/*Created on 2005-4-14*/ LfgR[!
package org.flyware.util.page; [>"qOFCr#:
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import org.apache.commons.logging.Log; <YJU?G:@
import org.apache.commons.logging.LogFactory; Zls4@/\Q
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/** lZn <v'y
* @author Joa C?hw$^w7T
* 6"_FjS3Sl
*/ Ypv"u0
publicclass PageUtil { uu#ALB
Jm
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privatestaticfinal Log logger = LogFactory.getLog $:
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(PageUtil.class); @*%.V.
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/** aYPzN<"%
* Use the origin page to create a new page ]4z?sk@
* @param page h ?p^DPo
* @param totalRecords ,HMB`vF
* @return cHJ
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*/ cp.)K!$
publicstatic Page createPage(Page page, int ^8V]g1]fiG
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totalRecords){ 1L &_3}
return createPage(page.getEveryPage(), evszfCH'J
w
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page.getCurrentPage(), totalRecords); }GGFJ"
} YJ!6)d?C.
C'5i>;
/** 5jYRIvM[Q~
* the basic page utils not including exception q~l&EH0
vn,L),"=
handler 0Y!Bb2m
* @param everyPage ~Dkje
* @param currentPage })"9TfC
* @param totalRecords M:C*?;K:
* @return page Z,u:g c+*
*/ rcQ?E=V2O
publicstatic Page createPage(int everyPage, int .6.oqb
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currentPage, int totalRecords){ J@yy2AZnO
everyPage = getEveryPage(everyPage); < ^J!*>
currentPage = getCurrentPage(currentPage); y f+/Kj<
a
int beginIndex = getBeginIndex(everyPage, uMqo)J@s
fNB*o={r|
currentPage); \h
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int totalPage = getTotalPage(everyPage, vEfX'gyk
r}vI#;&
totalRecords); [_H9l)
boolean hasNextPage = hasNextPage(currentPage, ICV67(Ui
YR[Ii?
totalPage); e1+
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boolean hasPrePage = hasPrePage(currentPage); Ye(0'*-jyc
OjZ+gl}
returnnew Page(hasPrePage, hasNextPage, qtgj"4,:`
everyPage, totalPage, O`Z>Oon?
currentPage, lYy0
~8|$KD4I
beginIndex); J.O;c5wL
} ,Xb :f/lB
$1UN?(r
privatestaticint getEveryPage(int everyPage){ rtUdL,Hx
return everyPage == 0 ? 10 : everyPage; S liF$}J
} St&XG>nWS
[!aHP?-
privatestaticint getCurrentPage(int currentPage){ 1uD}V7_y"
return currentPage == 0 ? 1 : currentPage; kW/ksz0)
} R?]>8o,
_
k>j?j-
privatestaticint getBeginIndex(int everyPage, int 7f
7*id
bg 7b!t1F
currentPage){ zM)o^Fn2
return(currentPage - 1) * everyPage; `d8$OC
} VT0I1KQx.
qnT:x{o
privatestaticint getTotalPage(int everyPage, int *9*I:Uh57
_s=[z$EN&
totalRecords){ ql_aDoj
int totalPage = 0; `#9ZP
5@Rf]'1B0
if(totalRecords % everyPage == 0) %=NqxF>>
totalPage = totalRecords / everyPage; cIq3En
else irrQ$N}
totalPage = totalRecords / everyPage + 1 ; W]reQ&<Z
EI/_=.d
return totalPage; 9-L.?LG
} 1L^\TC
v|n.AGn
privatestaticboolean hasPrePage(int currentPage){ &;C|=8eB
return currentPage == 1 ? false : true; #<l;YT8
} Ba@UX(t
|E!xt6B
privatestaticboolean hasNextPage(int currentPage, TNiFl hq
-<CBxyZa&
int totalPage){ JqFFI:Q5a
return currentPage == totalPage || totalPage == R#Ss_y
>5XE*9
0 ? false : true; 6IeHZ)jGj
} QvqX3FU
03{e[#6
(8{h I
} %Wu3$b
Is%-r.i
$'kIo*cZ
6B|IbQ^
4xg%OH
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 &4p:2,|r9
][#]4_
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 o3%Gc/6%
vE&
做法如下: 8Gs{Zfp!D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )<jj O
C2bN<K
的信息,和一个结果集List: |8V+(Vzl
java代码: OSsdB%bIu`
opdi5e)jK
'rU5VrK
/*Created on 2005-6-13*/ kM@8RAxA
package com.adt.bo; 6(X(f;MEl
d94Lc-kq^
import java.util.List; 3kQky
!=eui$]
import org.flyware.util.page.Page; @K2q*d
eV}Ow`~I5
/** N(&,+KJ)
* @author Joa JAc-5e4
*/ -*+7-9A I
publicclass Result { -:>Mi5/ s
8 w^i
private Page page; dN;C-XF3s
YV 2T$#7u
private List content; mI?AI7DqK
yv]/A<gP+
/** O z]iHe
* The default constructor oM
Q+=
*/ W
4~a`D7
public Result(){ %A:<rO85o
super(); ~B1)!5Z
} lc#su$xR>
;1K.SDj
/** O~l WFaW
* The constructor using fields 2["bS++?
* $oe:km1-D
* @param page mp>,TOi~s7
* @param content 7WKb|
/#;
*/ Gpo(Zf?
public Result(Page page, List content){ DMsxHAE1
this.page = page; rp+&ax}Wh
this.content = content; YN.rj-;^+
} $5s?m\!jZz
^4h/6^b0c
/** M&:[3u-
* @return Returns the content. +t,JCY6
*/ tNG0ft%a
publicList getContent(){ oj;Rh!O
return content; z~UqA1r
} (O"Wa
7GB>m}7
/** [;
* @return Returns the page. :l'61$=
*/ iQ~;to;Y
public Page getPage(){ IlN9IF\9L
return page; sy0|=E*;8"
} 7%b?[}y4
#kR8v[Z
/** {D={>0
* @param content 4l <%Q2
* The content to set. [:&4 Tp*C
*/ []}E-
V
public void setContent(List content){ )Gi!wm>zvN
this.content = content; &"p7X>bd
} ifHQ2Ug9
/5b,&
/** f!|7j}3
* @param page K-cRNt
* The page to set. S%uwQ!=O8
*/ U%.OH?;f
publicvoid setPage(Page page){ A NR?An
this.page = page; [K1RP.
} e`27 ?
} ue"?n2
yr8
b?m.x
X0wvOs:
}TI"j{(QJ
:08b&myx
2. 编写业务逻辑接口,并实现它(UserManager, plcz m 2
#e|G!'wdj
UserManagerImpl) qS1byqq78l
java代码: *DfwTbg|
lR3`4bHA
G0*>S`:4
/*Created on 2005-7-15*/ 9f1,E98w_
package com.adt.service; L?:.8k`d
}22h)){n#Y
import net.sf.hibernate.HibernateException; oMey^]!
}rK9M$2]u
import org.flyware.util.page.Page; lrrNyaFn
/&1FgSARK
import com.adt.bo.Result; Vcjmj
c"F3[mrff
/** Lmh4ezrdH
* @author Joa ul@G{N{L
*/ IP<]a5
publicinterface UserManager { uknX py))
%?
87#|
public Result listUser(Page page)throws $D&N^}alW
JO3"$s|t
HibernateException; P?WS=w*O0
iwM$U(
9
} lJlyfN
)c432).Z
LKC^Y)6o
L F<{/c9,
*BdKQ/Dk
java代码: )DG>omCY
g_8A1lt
9Kl:3C
/*Created on 2005-7-15*/ |-+ IF,j
package com.adt.service.impl; cl,\N\
yzI`&?
P2
import java.util.List; ?F=^&
v8
)SjhOvm
import net.sf.hibernate.HibernateException; 9szUN;:ZZ
n VNz5B
import org.flyware.util.page.Page; [T}Lq~
import org.flyware.util.page.PageUtil; GycW3tc]_&
esh7*,7-z*
import com.adt.bo.Result; "/ 9EUbca
import com.adt.dao.UserDAO; 3aX/)v.:4
import com.adt.exception.ObjectNotFoundException; PAYS~MnV@3
import com.adt.service.UserManager; >v?&&FhHK<
O-uno{Fd*
/** :)*+aS"
* @author Joa L|hoA9/]
*/ f\+ E&p.
publicclass UserManagerImpl implements UserManager { j-$F@p_2F
6<hE]B)
private UserDAO userDAO; od=x?uBVd
4-r5C5o,W
/** a]S0|\BkN
* @param userDAO The userDAO to set. |$:y8H'J
*/ d94Le/E
publicvoid setUserDAO(UserDAO userDAO){ '73g~T%$^*
this.userDAO = userDAO; .91@T.
} |d)*,O4s
D\H;_k8
/* (non-Javadoc) Y?'Krw `
* @see com.adt.service.UserManager#listUser uyqu n@q
-s6k't
(org.flyware.util.page.Page) iVSN>APe
*/ 'qy
LQ:6
public Result listUser(Page page)throws ! 'qY
WeiDg,]e$b
HibernateException, ObjectNotFoundException { Q1[3C(
int totalRecords = userDAO.getUserCount(); Y#<>N-X|kA
if(totalRecords == 0) Kj{(jT
throw new ObjectNotFoundException Abc%VRsT
YZdV0-S
("userNotExist"); N|5fkx<d^
page = PageUtil.createPage(page, totalRecords); ~W..P:wG5
List users = userDAO.getUserByPage(page); *,FU*zi
returnnew Result(page, users); "p@EY|Zv%I
} I<+i87=
MBn ZO
} 1DRih>+#
AW<"3 !@
% B^BN|r
DJJd_
MLT^7'y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q)[DSM
:B7dxE9[r
询,接下来编写UserDAO的代码: 80GBkFjV
3. UserDAO 和 UserDAOImpl: : *8t,f~s^
java代码: =1r!'<"h
zL!}YR@&u"
}bZb8hiG
/*Created on 2005-7-15*/ s1>d)2lX
package com.adt.dao; 7!g"q\s
PpLuN12H
import java.util.List; OK" fFv
<~teD[1k"
import org.flyware.util.page.Page; O|AY2QH\
!O 0{ .k
import net.sf.hibernate.HibernateException; +~n4</
2|A?9aE%0
/** eA_]%7+`
* @author Joa 4DgH/Yo
*/ `$t|O&z
publicinterface UserDAO extends BaseDAO { z'&tmje[?
k+@,m\tE
publicList getUserByName(String name)throws Q2 Dh(
25Uw\rKeO
HibernateException; ^AF~k#R
M2Jb<y]
publicint getUserCount()throws HibernateException; Wud-(19
kB9@
&t+
publicList getUserByPage(Page page)throws B|K^:LUk9
8o i{%C&-
HibernateException; 5)C`W]JE
k&9[}a*
} #.{ddY{
8ly6CP+^B
\0n<6^y
` >loleI
^c]c`w
java代码: ^'p!#\T;H
a+^,EY
ws<pBC,m
/*Created on 2005-7-15*/ u'T?e+=
package com.adt.dao.impl; []G@l. ]W
O7oq1JI]Y
import java.util.List; O%f{\Fr
f#McTC3C
import org.flyware.util.page.Page; 3BSZz%va
P@5}}vwS
import net.sf.hibernate.HibernateException; PqMu2 e
import net.sf.hibernate.Query; Z*n4$?%W
i&q_h>ZTg
import com.adt.dao.UserDAO; OX7a72z
+4+czfz
/** TBZhL
* @author Joa R*?!xDJ
*/ zY2x_}#Q\"
public class UserDAOImpl extends BaseDAOHibernateImpl pfR~?jYzm
=zTpDL
implements UserDAO { Wuk!\<T{
5me#/NqLHY
/* (non-Javadoc) 7x]q>Y8T
* @see com.adt.dao.UserDAO#getUserByName ;9<?~S
}USOWsLSt
(java.lang.String) klMpiy
*/ XQ2YUe]DJ
publicList getUserByName(String name)throws >)HKruSW.
'w=aLu5dY
HibernateException { T7|=`~
String querySentence = "FROM user in class @{Dfro
Tb!FO"o
com.adt.po.User WHERE user.name=:name"; ?zf3AZ9
Query query = getSession().createQuery x`Wb9[u8
%f?Zg44
(querySentence); 9fWR8iV
query.setParameter("name", name); jZH4]^De
return query.list(); #ro$$I;
} <\$?.tTZ{
2D a0*xn{
/* (non-Javadoc) q VavP6I
* @see com.adt.dao.UserDAO#getUserCount() %{Obhj;c
*/ "Th;YJu
publicint getUserCount()throws HibernateException { RY3=UeoF
int count = 0; ("YWJJ'H
String querySentence = "SELECT count(*) FROM JmeE}:5lpj
| )br-?2
user in class com.adt.po.User"; F'"-aB ~
Query query = getSession().createQuery RN}joKV
8Zy*#[-
(querySentence); 'V8o["P
count = ((Integer)query.iterate().next +_25E.>ml
EPA
2_
()).intValue(); ?]aVRmL
return count; n]7rHV}G
} t1~k+
r;{ggwY&J
/* (non-Javadoc) -d thY(8
* @see com.adt.dao.UserDAO#getUserByPage gvPHB+#A
}{kn/m/
(org.flyware.util.page.Page) pju*i6z
*/ tc{l?7P
publicList getUserByPage(Page page)throws K7C!ZXw~
9Zf
HibernateException { |`pBI0Sjo
String querySentence = "FROM user in class _
nz^+
\t`Vq JLyu
com.adt.po.User"; atW^^4:
Query query = getSession().createQuery %_!0V*X*
nf[KD,f
(querySentence); \Ui8gDJ8y5
query.setFirstResult(page.getBeginIndex()) BG)zkn$
.setMaxResults(page.getEveryPage()); 4sX?O4p
return query.list(); _zzT[}
} j+S&5C/{
:'xZF2
}
DZ4gp
t=My=pG
!I\eIV>0b
9G"4w` P
Yakrsi/jV}
至此,一个完整的分页程序完成。前台的只需要调用 F >^KXq:Z
3sIdwY)ZS_
userManager.listUser(page)即可得到一个Page对象和结果集对象 MmU`i ,z
vl6|i)D
的综合体,而传入的参数page对象则可以由前台传入,如果用 #T8jHnI
YMy**
webwork,甚至可以直接在配置文件中指定。 8zcSh/
P #8+1iC1
下面给出一个webwork调用示例: pAqPHD=
java代码: wDSwcNS
:7X{s4AU6
{.0I!oWv
/*Created on 2005-6-17*/ +?*.Emzl@
package com.adt.action.user; [Jjo H1E@
t/%[U,m
import java.util.List; _VM}]A
#c"05/=A
import org.apache.commons.logging.Log; ux*G*QZ
import org.apache.commons.logging.LogFactory; 1}SON4U
import org.flyware.util.page.Page; Sn
7h$
j|qdf3^f
import com.adt.bo.Result; 'vZy-qHrV
import com.adt.service.UserService; ??|,wIRz
import com.opensymphony.xwork.Action; R#?atL$(
<Wj/A/
/** ftRdK>a
D
* @author Joa oK<H/76x
*/
Jk:ZO|'Z
publicclass ListUser implementsAction{ UF\k0oLz
:/Z1$xS
privatestaticfinal Log logger = LogFactory.getLog Q,tjODc6n
N6T
(ListUser.class); y5D3zqCG
qI
tbY%
private UserService userService; D vN0h(?
- K"L6m|
private Page page; M\Wg|gpy
2#CN:b]+
privateList users; >MhZ(&iD
HCYy9
/* MCIuP`sC|
* (non-Javadoc) P]2 /}\f
* _j{)%%?r
* @see com.opensymphony.xwork.Action#execute() )(1tDQ`L>
*/ ^)$T`
publicString execute()throwsException{ <]#_&Na
Result result = userService.listUser(page); zxd<Cq>d
page = result.getPage(); P.=Dd"La
users = result.getContent(); W>,D$
return SUCCESS; ]n'.}"8Kn
} onS4ZE3B
jH;L7
/** ]/%CTD(O
* @return Returns the page. \[8uE,=|
*/ ]C|xo.=?]
public Page getPage(){ %RzkP}1>E
return page; j.V7`x
} bHTTxZ-%
<K/iX%b?
/** nn">
* @return Returns the users. Iu;VFa
*/ xyXVWd[
publicList getUsers(){ G!Y7RjWD
return users; m
(kKUv
} o_ixdnc
Z%SDN"+'g
/** g`"_+x'
* @param page Qi9M4Yv
* The page to set. ws,VO*4
*/ lZ`@ }^&
publicvoid setPage(Page page){ :&RpB^]
this.page = page; Ro2!$[P
} "9y0]~
sE^=]N
/** @ "CP@^
* @param users K2tOt7M!
* The users to set. )Oj{x0{\Q
*/ A{DE7gp!
publicvoid setUsers(List users){ Z22#lF\ N
this.users = users; e\*N Lj_(
} C}:_&^DQ
S;nlC
/** o4aFgal1
* @param userService ^X:g C9
* The userService to set. T@r%~z
*/ CraD
publicvoid setUserService(UserService userService){ KM-7w66V
this.userService = userService; 88DMD"$B
} eTY(~J#'
} >T^BD'z@'
l<s6Uu"
dp'k$el
[R/'hH5
<bh!wf6;
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;1ZMHD
GVM)-Dp]
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 (;++a9GK
[|L~" BB
么只需要: $~1~+s0$
java代码: /nNrvMtv
.;;:t0PB
cN]g^
<?xml version="1.0"?> NH8\}nAK
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _%PEv{H0.
mX@!O[f%9e
1.0//EN" "http://www.opensymphony.com/xwork/xwork- vu_ u\2d
;0O>$|kg
1.0.dtd"> #pWeMt'
~J|B
<xwork> CVGQ<,KVW
"pQ)5/e
<package name="user" extends="webwork- oP`Qyk
u 9kh@0
interceptors"> PO]c&}/
:qK^71gz
<!-- The default interceptor stack name 7[YulC-pH
[^\HP]*Q{
--> N7dI}ju
<default-interceptor-ref PKX
Tj6hj)
j>|mpfU
name="myDefaultWebStack"/> 7DWHADr
e!1am%aE
<action name="listUser" &h;J_Ps
)t$o0!
class="com.adt.action.user.ListUser"> <PpW.1w
<param #PA 9bM
$/$ 5{<
name="page.everyPage">10</param> }+GIrEDId
<result 7tU=5@M9D
Og9:MFI
name="success">/user/user_list.jsp</result> e<HHgC#J
</action> i-`J+8|d
E)Cdw%}^
</package> qnTW?c9Z5
2D'$
</xwork> 9wpV} .(
~zL DLr=
}"6
PM)s
asKAHVT(
^(T_rEp
"4/J4'-
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 1'BC
R
Vae=Yg=fw
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。 .5GGZfJ]
2#`9OLu8X
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 _?c7{
tY!GJusd
H.*aVb$
4ZrRgx2MD
Z:Y_{YAD
我写的一个用于分页的类,用了泛型了,hoho XSe\@t~&g
L_Lhmtm}m
java代码: ,]_<8@R
lkaWwjv_D
HCZVvsG
package com.intokr.util; 8;"HM5+
b+e9Pi*\
import java.util.List; #B!<gA$/
WADAp\&
/** =RjseTS
* 用于分页的类<br> ] Wx?k7T
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Ktn:6=,
* #(G"ya
* @version 0.01 a?8boN(
* @author cheng w>TTu:
7
*/ -X_dY>>s
public class Paginator<E> { dd:vQOF;
privateint count = 0; // 总记录数 W*^_Ul|
privateint p = 1; // 页编号 hK 1 H'~c
privateint num = 20; // 每页的记录数 !YENJJ
privateList<E> results = null; // 结果 jkV9$W0
nUf0TkA
/** s%i
\z }/
* 结果总数 fRomP-S
*/ LW!>_~g-
publicint getCount(){ h8hyQd$!
return count; ;2[o>73F
} XNQPyZ2@|b
l-?#oy
publicvoid setCount(int count){ g<g$c<sm
this.count = count; Ox9M![fC
} A\ r}V-
x,LYfy"0
/** y_LFkZ
* 本结果所在的页码,从1开始 =buarxk
* (CInt_dBw~
* @return Returns the pageNo. iCtS<"@Yx
*/ =B0AG9Fz
publicint getP(){ 8,-U`.
return p; /z`.- D(
} 1'f&
/p$+oA+
/** jr/IU=u*v
* if(p<=0) p=1 W0XfU`
* !3`X Gg
* @param p zx7A}rs3oX
*/ KW(^-:wmr
publicvoid setP(int p){ jM:|%o
if(p <= 0) ng:B;;
m
p = 1; [xo-ZDIoG
this.p = p; m
;yIFO
} Q[)3r
,D
=
( 4l
/** p# JPLCs
* 每页记录数量 {LBL8sG
*/ l'7'G$v
publicint getNum(){ X}g"_wN,g>
return num; -+[~eqRB
} {9vMc
OV|n/~
/** zMh`Uqid
* if(num<1) num=1 NZz^* Ela
*/ z}F^HQ1
publicvoid setNum(int num){ )M*Sg?L
if(num < 1) -ufaV#
num = 1; JqV}$E"M2
this.num = num; C5Mpm)-%
} .rQcg.8/B
EQ]>^VE2B
/** e[6Me[b
* 获得总页数 Zn:]?%afdO
*/ a]!u
go}
publicint getPageNum(){ ^%O$7*
return(count - 1) / num + 1; 5Gm8U"UR
} m[ER~]L/C
;
W$.>*O
/** ']N\y6=fn9
* 获得本页的开始编号,为 (p-1)*num+1 `aSbGMz
*/ 5t|$Yt[
publicint getStart(){ `>=@Kc
return(p - 1) * num + 1; ~:*V'/2k
} A4/gVi|
=.l>Uw!
/** &5*t*tI
* @return Returns the results. *0m|`-
T
*/ 9'p*7o
publicList<E> getResults(){ !QCErE;r
return results; Y.kc,~vYL
} xl Q]"sm1
!&5|:96o
public void setResults(List<E> results){ :;\xyy}A
this.results = results; :lu "14
} Zzmo7kFx3
lT~WP)
public String toString(){ %vbov}R
StringBuilder buff = new StringBuilder u+c2
m
,+X:#$
(); 8:2Vib$
buff.append("{"); $01~G?:]`
buff.append("count:").append(count); +BE_t(%p"
buff.append(",p:").append(p); /J9Or{#r
buff.append(",nump:").append(num); aGAr24]y
buff.append(",results:").append dh1 N/[
kOC0d,
(results); 0}po74x*r
buff.append("}"); (B%[NC6
return buff.toString(); w|NI d,#f
} >_$_fB
=E-o@#BS
} OzR<jCOS
bDD29
/FjdcH=