Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bhqSqU}6~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Y![Q1D!
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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 0gd`W{YP
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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 7~Y\qJ4b
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分页支持类: {&=+lr_h?
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java代码: TN(Vzs%
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package com.javaeye.common.util;
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import java.util.List; @Rr=uf G
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publicclass PaginationSupport { .-d'*$
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publicfinalstaticint PAGESIZE = 30; mZ+!8$1X
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privateint pageSize = PAGESIZE; >JpBX+]5m
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privateList items; v:t;Uk^Y
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privateint totalCount; a:BW*Hy{\
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privateint[] indexes = newint[0]; )?F&`+
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privateint startIndex = 0; VOEV[?>ss
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public PaginationSupport(List items, int Bs "D<r&ro
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totalCount){ uo#1^`P
setPageSize(PAGESIZE); J(7#yg%5
setTotalCount(totalCount); !oWB5x~:P
setItems(items); daE.y_9y
setStartIndex(0); ;b<w'A_1
} '`>%RZ]
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public PaginationSupport(List items, int 9@ k8$@
&dyQ6i$],
totalCount, int startIndex){ ,!#Am13
setPageSize(PAGESIZE); Gv-VDRS
setTotalCount(totalCount); Q:-T'xk@
setItems(items); TnF~'RZYb
setStartIndex(startIndex); C[J9 =!t
} -D`1z?zHra
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public PaginationSupport(List items, int &
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{wqT$( (<
totalCount, int pageSize, int startIndex){ bb6x} jR
setPageSize(pageSize); (GJtTp~2C4
setTotalCount(totalCount); _Mw3>GNl
setItems(items); D2$9$xeR
setStartIndex(startIndex); UB$}`39@
} L'+bVP{L
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publicList getItems(){ [`n_> p!
return items; =U]9>
} OX_y"]utU
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publicvoid setItems(List items){ LV:L0D7y
this.items = items; R(1:I@<?E
} hA7=:LG
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publicint getPageSize(){ 5YY5t^T
return pageSize; :""HyjY!
} 'RjEdLrI
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publicvoid setPageSize(int pageSize){ _.5{vGyxr
this.pageSize = pageSize; 'OY4Q'Z
} &Hoc`u
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publicint getTotalCount(){ yE:y[k0E
return totalCount; j~q 7v
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} y=Y k$:-y
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publicvoid setTotalCount(int totalCount){ .n8R%|C5
if(totalCount > 0){ (xfc_h*xA
this.totalCount = totalCount; *:%&z?<Fw
int count = totalCount / !0;AFv`\
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pageSize; fn}E1w
if(totalCount % pageSize > 0) ~+Wx\:TT
count++; vjEDd`jYZ
indexes = newint[count]; K~L&Z?~|E
for(int i = 0; i < count; i++){ 7`|'Om?'
indexes = pageSize * R@c] )\^]
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} ,GSiSn
}else{ +( LH!\{^
this.totalCount = 0; #-L0.z(
} &~:EmLgv
} de:@/-|
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publicint[] getIndexes(){ 0#V"
return indexes; be+-p
} 6#z8 %kaX
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publicvoid setIndexes(int[] indexes){ v "l).G?
this.indexes = indexes; u?,>yf.;s
} X!KX4H
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publicint getStartIndex(){ MCE@EFD`\
return startIndex; lR?y
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} !tq]kKJ3:
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publicvoid setStartIndex(int startIndex){ - Jaee,P
if(totalCount <= 0) ZF7n]LgSc&
this.startIndex = 0; g QBS#NY
elseif(startIndex >= totalCount) bxa>:71
this.startIndex = indexes xp|1yud
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[indexes.length - 1]; gC$_yd6m
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elseif(startIndex < 0) @qNY"c%HV
this.startIndex = 0; 3@~a)E}T
else{ ilL%
this.startIndex = indexes bF _]j/
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[startIndex / pageSize]; &eMd^l}:#
} tl dK@!E3
} ,!Wo6{'
%{
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publicint getNextIndex(){ h1~h&F?
int nextIndex = getStartIndex() + %pVsafV
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pageSize; "](Q2
if(nextIndex >= totalCount) wR_mJMk_
return getStartIndex(); <zXG}JuL@T
else EjfQF C
return nextIndex; EV6R[2kl
} b
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publicint getPreviousIndex(){ .>W [
int previousIndex = getStartIndex() - R+!U.:-yz
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pageSize; ;!f='QuA
if(previousIndex < 0) |uy@v6
return0; n
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else "|JbdI]%P
return previousIndex; xoVd[c!
} \PS]c9@,rc
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} k<*v6
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抽象业务类 DOyO`TJi
java代码: M4Cb(QAVP
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/** GP+=b:C{E
* Created on 2005-7-12 h] ho? K
*/ ;?u cC@
package com.javaeye.common.business; pj_W^,*/
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import java.io.Serializable; D2VYw<tEA
import java.util.List; |ru!C(
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import org.hibernate.Criteria; eFsl
import org.hibernate.HibernateException; h GA2.{
import org.hibernate.Session; yr'-;-u
import org.hibernate.criterion.DetachedCriteria; Xc[ym
import org.hibernate.criterion.Projections; )ThNy:4
import *
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org.springframework.orm.hibernate3.HibernateCallback; NK|U:p2H
import u>;aQtK~
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org.springframework.orm.hibernate3.support.HibernateDaoS u.q3~~[=
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upport; |8E~C~d
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import com.javaeye.common.util.PaginationSupport; yLf9cS6=
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public abstract class AbstractManager extends ItLR|LO9
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HibernateDaoSupport { Kz
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privateboolean cacheQueries = false; 9+ Mj$
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privateString queryCacheRegion; P,ZQ*Ju
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publicvoid setCacheQueries(boolean > 3&
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cacheQueries){ SN)Czi#7
this.cacheQueries = cacheQueries; xJw"
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} 3B;Gm<fJ9N
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publicvoid setQueryCacheRegion(String [;hkT
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queryCacheRegion){ V=fu[#<@Ig
this.queryCacheRegion = %@%rdrZ
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queryCacheRegion; L+ew/I>:
} q5Zu'-Cx@
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publicvoid save(finalObject entity){ 8p829
getHibernateTemplate().save(entity); FS8l}t
} <VU-ja*(J
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publicvoid persist(finalObject entity){ uxdB}H,
getHibernateTemplate().save(entity); E`LaO
} t ^>07#z
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publicvoid update(finalObject entity){ Q~"Lyy8
getHibernateTemplate().update(entity); /Q W^v;^
} SeZ+&d
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publicvoid delete(finalObject entity){ /T
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getHibernateTemplate().delete(entity); 7V^j9TC
} k6DJ(.n'%a
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publicObject load(finalClass entity, f4\F:YT
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finalSerializable id){ ;~
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return getHibernateTemplate().load mx1Bk9h%Xe
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(entity, id); Nq9pory^
} )6XnxBSH
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publicObject get(finalClass entity, z1tD2jL _
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finalSerializable id){ (=rDt93J
return getHibernateTemplate().get E\Wd*,/v)
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(entity, id); us5Zi# }
} K
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publicList findAll(finalClass entity){ )s7 EhIP
return getHibernateTemplate().find("from "=%YyH~WY
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" + entity.getName()); qDg`4yX.}
} T+0z.E!~I
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publicList findByNamedQuery(finalString g<F+Ldgj
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namedQuery){ Gn6\n'r0
return getHibernateTemplate .@r{Tq,%q8
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().findByNamedQuery(namedQuery); EQ"_kJ>81Y
} )2Q0NbDn
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publicList findByNamedQuery(finalString query, 8>|4iT
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finalObject parameter){ #6y fIvap
return getHibernateTemplate {?w*n_T.
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().findByNamedQuery(query, parameter); Grw[h
} 2fayQY
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publicList findByNamedQuery(finalString query, / E!6]b/
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finalObject[] parameters){ aFnyhu&W'
return getHibernateTemplate ?=?*W7
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().findByNamedQuery(query, parameters); dhg($m
} zb~;<:<
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publicList find(finalString query){ .1h\r,
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return getHibernateTemplate().find 4y.'O
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(query); @d5t%V\
} BVv-1$ U^
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publicList find(finalString query, finalObject 7
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parameter){ DjZTr}%q
return getHibernateTemplate().find blG?("0!
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(query, parameter); #RdcSrw)W!
} HWL? doM
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public PaginationSupport findPageByCriteria _=[pW2p
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(final DetachedCriteria detachedCriteria){ 0ikA@SAq
return findPageByCriteria : @gW3'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /lHs]) ,
} ev7A;;
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public PaginationSupport findPageByCriteria RY,L'GtO
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(final DetachedCriteria detachedCriteria, finalint 't\sXN+1
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startIndex){ ]]u_Mdk
return findPageByCriteria rJp9ut'FEz
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(detachedCriteria, PaginationSupport.PAGESIZE, s}^W2
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startIndex); DM,;W`|6%
} ~2NTXp
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public PaginationSupport findPageByCriteria !*wd
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(final DetachedCriteria detachedCriteria, finalint \u/=?b
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pageSize, <qoPBm])
finalint startIndex){ c!$~_?]
return(PaginationSupport) 1JGww]JZo
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getHibernateTemplate().execute(new HibernateCallback(){ xnZ
publicObject doInHibernate EL
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(Session session)throws HibernateException { {!4ZRNy(k
Criteria criteria = t/]za4w/
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detachedCriteria.getExecutableCriteria(session); Hw#yw g
int totalCount = Yk7^?W
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((Integer) criteria.setProjection(Projections.rowCount JS >"j d#
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()).uniqueResult()).intValue(); r_V^sX
criteria.setProjection Ys5Iqj=mp
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(null); >ZAn2s
List items = {mHxlG)
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criteria.setFirstResult(startIndex).setMaxResults 9\r5&#<(I
gi/W3q3c6
(pageSize).list(); 5) 4?i p
PaginationSupport ps = 8?o{{ay
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new PaginationSupport(items, totalCount, pageSize, :y!{=[>M(
yAJrdY"
startIndex); %)r1?H} #%
return ps; y$|OE%S
} y= 1(o3(
}, true); ,ce$y4%(
} 7ws[Rp8
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public List findAllByCriteria(final BLo=@C%w5
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DetachedCriteria detachedCriteria){ W$R@Klz
return(List) getHibernateTemplate !`dn# j
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().execute(new HibernateCallback(){ nlx~yUXL4
publicObject doInHibernate d:n.Vp
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(Session session)throws HibernateException { )]JQlm:H
Criteria criteria = l'\m'Ioh
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detachedCriteria.getExecutableCriteria(session); QJH~YV\%
return criteria.list(); IkLcL8P^
} E-#}.}i5
}, true); a&`Lfw"
} ]u
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public int getCountByCriteria(final Z@#kivcpz
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DetachedCriteria detachedCriteria){
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Integer count = (Integer) A@ G%*\UZ
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getHibernateTemplate().execute(new HibernateCallback(){ ~,84E [VV
publicObject doInHibernate 2MKB(;k
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(Session session)throws HibernateException { l9$"zEC
Criteria criteria = [Kanj/
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detachedCriteria.getExecutableCriteria(session); )!D,;,aQ
return #Bas+8
@,
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criteria.setProjection(Projections.rowCount meyO=>
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()).uniqueResult(); :W1B"T<
} 4"%LgV`
}, true); M[ ,:NE4H
return count.intValue(); 09HqiROw
} !JwR[X\f
} K!SFS
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用户在web层构造查询条件detachedCriteria,和可选的 #;>v,Jo
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2xpI|+a%
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PaginationSupport的实例ps。 n ]P,5
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ps.getItems()得到已分页好的结果集 j |ZhGerp
ps.getIndexes()得到分页索引的数组 JE/Kf<
ps.getTotalCount()得到总结果数 !&vPG>V
ps.getStartIndex()当前分页索引 (%iCP/E3
ps.getNextIndex()下一页索引 [-JU(:Rh
ps.getPreviousIndex()上一页索引 zM|Y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 |]x>|Z?/u
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 qgw)SuwW
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一下代码重构了。 p u6@X7W"
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我把原本我的做法也提供出来供大家讨论吧: w|8T6W|w
jB%aHUF;
首先,为了实现分页查询,我封装了一个Page类: -1tiy.^$F
java代码: L+2<J,
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/*Created on 2005-4-14*/ jZ> x5 W
package org.flyware.util.page; F>[T)t{m=
y` 6!Vj l
/** YS+|n%?
* @author Joa zqa7!ky
* FWDAG$K@0
*/ C{U"Nsu+1
publicclass Page { 'o]8UD(
zP|^) h5
/** imply if the page has previous page */ Y4I;-&d's
privateboolean hasPrePage; 58o'Q
jLv8K
/** imply if the page has next page */ 4S3uzy%
privateboolean hasNextPage; 6ly`lu9
{#4F}@Q
/** the number of every page */ j)b[7%
privateint everyPage; gano>W0
d\v1R-V
/** the total page number */ :"I!$_E'
privateint totalPage; yJ?S7+b
q=`i
/** the number of current page */ "TP^:Ln
privateint currentPage; GEUC<bL+
S<UWv@`U"
/** the begin index of the records by the current 0;2"X[e
Y2Y)| <FH
query */ b]k9c1x
privateint beginIndex; M.?[Xpa
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/** The default constructor */ sA!$}W
public Page(){ 2c1L[]h'
fm1yZX?`
} Wg!JQRHtT
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/** construct the page by everyPage yttaZhK^u
* @param everyPage kBg8:bo~
* */ aGq1YOD[$
public Page(int everyPage){ q1?}G5a?
this.everyPage = everyPage; :B
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} \2!1fN
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/** The whole constructor */ 6tF_u D
public Page(boolean hasPrePage, boolean hasNextPage, m< Y I}
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int everyPage, int totalPage, $*hqF1Q
int currentPage, int beginIndex){ sFV&e->AN\
this.hasPrePage = hasPrePage; xTg=oq
this.hasNextPage = hasNextPage; N`et]'_A}
this.everyPage = everyPage; t4v@d
this.totalPage = totalPage; a|eHo%Qt
this.currentPage = currentPage; TP{2q51yM
this.beginIndex = beginIndex; yXT8:2M
} Ra/Pk G-7
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/** 7m:ZG
* @return (NC]S
* Returns the beginIndex. E.eUd4XG
*/ _9:r4|S
publicint getBeginIndex(){ 2mEvoWnJ
return beginIndex; mLm?yb:
} 7!U^?0?/
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/** Fj4>)!^kM
* @param beginIndex *WaqNMD[%
* The beginIndex to set. N> xdX5
*/ j9xu21'!%
publicvoid setBeginIndex(int beginIndex){ )k.}>0K |
this.beginIndex = beginIndex; 5XoM)
} h?'~/@
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/** U*4r<y9R
* @return sm"s2Ci=}
* Returns the currentPage. ,0a\Ka{^
*/ ( 4(,"
publicint getCurrentPage(){ "fu:hHq
return currentPage; fPPC`d&Q3
} ir|c<~_=
Kk`LuS?
/** r4m z
* @param currentPage \zKO5,qw
* The currentPage to set. &P7Z_&34Z
*/ ,49Z/P
publicvoid setCurrentPage(int currentPage){ bEm9hFvd
this.currentPage = currentPage; 8PR\a!"
} L3=5tuQ[5
Qk72ra)
/** +/ rt'0o
* @return V]NCFG
* Returns the everyPage. Z+=M_{`{
*/ 1Li*n6tLX`
publicint getEveryPage(){ slzB#
return everyPage; y9b%P]i
} <*(^QOM
l];/,J^
/** 6n^@Ps
* @param everyPage
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* The everyPage to set. u4j"U6"]M
*/ Y>6N2&Q
publicvoid setEveryPage(int everyPage){ )2a)$qx;
this.everyPage = everyPage; ]I_*+^?tI
} \PWH(E9
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/** 0SDnMij&bf
* @return #%EHcgF
* Returns the hasNextPage.
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*/ b~qH/A}h
publicboolean getHasNextPage(){ hd6O+i
Y4
return hasNextPage; ?lML+
} %&S9~E
D
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/** 2+_a<5l~
* @param hasNextPage ,l Y4WO
* The hasNextPage to set. Xv3pKf-K
*/ TJ1h[
publicvoid setHasNextPage(boolean hasNextPage){ Wy%FF\D.Y
this.hasNextPage = hasNextPage; "([/G?QAG
} h+ud[atk.
tuLNGU
/** T<-_#}.Hn
* @return Ss%1{s~ok
* Returns the hasPrePage. M*f]d`B
*/ 4(p`xdr}K
publicboolean getHasPrePage(){ 5vg="@O K
return hasPrePage; (zh[1[a
} tva=DS
NBHpM}1xtU
/** C~R
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* @param hasPrePage f}J(nz>Sh
* The hasPrePage to set. ]f0OmUHR5i
*/ 1
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publicvoid setHasPrePage(boolean hasPrePage){ T7%!JBg@
this.hasPrePage = hasPrePage; L$BV`JWPw
} {
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N<1+aL\
/** -]+pwZ4g
* @return Returns the totalPage. "F%JZO51
* [q Uv|l1
*/ vxHFNGI
publicint getTotalPage(){ r!
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return totalPage; !|up"T I
} 0EF~Ouef
(|F.3~Amq
/** $rI 1|;^
* @param totalPage Fn7OmxfD
* The totalPage to set. Qn,6s%n
*/ _&/ {A|n
publicvoid setTotalPage(int totalPage){ a6-.|tt#t
this.totalPage = totalPage; Px&_6}YWy
} 1I{8 |
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} A&bj l[s
a]T&-#c,}
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1"L"LU'
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 !~yBzH;K
bi^?SH\
个PageUtil,负责对Page对象进行构造: HA*L*:0
java代码: ,T`,OZm
y?3.W
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/*Created on 2005-4-14*/ (v%24bv
package org.flyware.util.page; Q{RmE:
H=Ilum06
import org.apache.commons.logging.Log; KVJ,
a
import org.apache.commons.logging.LogFactory; (Xcy/QT
? ep#s$i
/** bD{k=jum
* @author Joa uO`MA%
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* O|~C qb
*/ EgU#r@7I
publicclass PageUtil { =jJEl=*S
V@!)Pw
privatestaticfinal Log logger = LogFactory.getLog 4uo`XJuQ
[104;g <
(PageUtil.class); a9z#l}IQ
m^G(qoZ]
/** P0jr>j@^-
* Use the origin page to create a new page yB2h/~+
* @param page p.SipQ.P
* @param totalRecords :t]HY2
* @return Pps-,*m
*/ {@^;Nw%J
publicstatic Page createPage(Page page, int B+j]C$8}
<ZF|2
totalRecords){ r~lZ8$KC
return createPage(page.getEveryPage(), P}Kgh7)3
k(l2`I4V
page.getCurrentPage(), totalRecords); O,%,dtD[a
} w{6C4~0
Wc[,kc
/** a/,>fv9;$
* the basic page utils not including exception w8UuwFG?<
r8Mx+r
handler fq]PKLW'
* @param everyPage AO$AT_s
* @param currentPage g4$(%]
* @param totalRecords n%s%i-[5B
* @return page \A"o[A2v
*/ -f)fiQ-<
publicstatic Page createPage(int everyPage, int i(^U<DW$
{P]C>
currentPage, int totalRecords){ W(`QbNJ
everyPage = getEveryPage(everyPage); #_@cI(P
currentPage = getCurrentPage(currentPage); 3KkfQ{
int beginIndex = getBeginIndex(everyPage, LdV&G/G-#D
S{rltT-
currentPage); rP3HR5
int totalPage = getTotalPage(everyPage, &0Yg:{k$
.p&@;fZ
totalRecords); *h!fqT%9
boolean hasNextPage = hasNextPage(currentPage, _U<fS
/|1p7{km
totalPage); /Vn>(;lo
boolean hasPrePage = hasPrePage(currentPage); !Qe;oMqy}
aa`(2%(:
returnnew Page(hasPrePage, hasNextPage, ej`%}e%2
everyPage, totalPage, MC}t8L=
currentPage, XH"+oW
/x6p
beginIndex); a /sj W
} `hi=y BO
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privatestaticint getEveryPage(int everyPage){ $zMshLT
return everyPage == 0 ? 10 : everyPage; mll:rWC)
} _h~ksNm5u
0=j }`
privatestaticint getCurrentPage(int currentPage){ lW&(dn)}
return currentPage == 0 ? 1 : currentPage; ~2w&+@dV%
} <W80A J
pk/#RUfT+
privatestaticint getBeginIndex(int everyPage, int H\67Pd(Z6
h[ DNhR
currentPage){ $J`O-"M
return(currentPage - 1) * everyPage; h:YD$XE
} \k.`xG?
?Z7`TnG$uf
privatestaticint getTotalPage(int everyPage, int r~t`H*C)}
jxh:z
totalRecords){ WQK<z!W5
int totalPage = 0; m+kP"]v
{^VtD
if(totalRecords % everyPage == 0) W$rWg>4>
totalPage = totalRecords / everyPage; ~RhUg~o
else #jQauO
totalPage = totalRecords / everyPage + 1 ; J7+G"_)'
K4c:k;
V
return totalPage; Jz}nV1G(jz
} #DTKz]i?
/4:bx#;A
privatestaticboolean hasPrePage(int currentPage){ 1i76u!{U
return currentPage == 1 ? false : true; _ E;T"SC
} Zv u6/#
Z/#_Swv
privatestaticboolean hasNextPage(int currentPage, w,LtQhQ
CLR1CGnn7
int totalPage){ O
VV@
return currentPage == totalPage || totalPage == xM*_1+<dT$
B$4*U"tk
0 ? false : true; 3S0.sU~_U
} U0~_'&Fe
?+yr7_f3*
mmAm@/
} _pvB$&
lvs
XL
hi7_jl6
ToXWFX
`fu_){
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。 @I_cwUO
I{Zb/}k-
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 RLmOg{L
WE<?y_0y&
做法如下: N9e'jM>Oos
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "TV'}HH
4CNrIF@
的信息,和一个结果集List: D*XrK0#Z`
java代码: QQ*sjK.(
J1?;'
2"Os9 KD
/*Created on 2005-6-13*/ ^9g$/8[^c_
package com.adt.bo; z;c>Q\Q
b$ G{^
import java.util.List;
FaL\6w
1^~&"s U
import org.flyware.util.page.Page; (o^tmH*
"HMEoZ
/** {keZ_2
* @author Joa 1|bXIY.J*
*/ +#}GmUwPG$
publicclass Result { eA/n.V$z
$@g]?*L:
private Page page; ~6[?=mOi'
p@<Q?
private List content; &OMlW_FHR
V>@[\N[
/** U&!TA(Yr
* The default constructor j#NyNv(jE1
*/ @CMI$}!{V
public Result(){ =~#mF<z5
super(); j{@O%fv=
} 4ot<Uw5
VF%QM;I[Rc
/** !ifU}qFzK
* The constructor using fields DeO-@4+qKd
* FXQWT9Kk~_
* @param page ke4E1T-1n
* @param content #EzBB*kP
*/ Dd3f@b[WX
public Result(Page page, List content){ -;""l{
this.page = page; =o@;K~-
this.content = content; 48^-]};
} qt"D!S_
A2_ut6&eb
/** :6n#y-9^1
* @return Returns the content. o+A7hBM^
*/ mw@Pl\=
publicList getContent(){ +C(-f
return content; H4$qM_N
} 'o AmA=
GABZsdFZ!
/** xL}i9ozZ
* @return Returns the page. w^yb`\$
*/ l45/$G7
public Page getPage(){ LUOjaX
return page; JGs:RD'
} --yF%tRMP
h\s/rZg=r
/** HiCh:IP7>/
* @param content EX8JlA\-W
* The content to set. yx-{PjX
*/ v 6 ~9)\!j
public void setContent(List content){ ,7{|90'V<
this.content = content; /K=OsMl2b8
} Hon2;-:]{]
8 Rx@_
/** i8iT}^
* @param page 5`;SI36"
* The page to set. r- 8Awa
*/ 6$u/N gS
publicvoid setPage(Page page){ iw@rW5%'~
this.page = page; 5ggyk0
} aZ#FKp^8H
} c<lp<{;
l.Q
y>o:5':;'
0~|0D#klB
Z8v\>@?5R
2. 编写业务逻辑接口,并实现它(UserManager, ]OAU&t{
<Q[%:LD
UserManagerImpl) |t,sK aL
java代码: 9~SPoR/_0
x :SjdT
<=(K'eqC^
/*Created on 2005-7-15*/ `<XS5h
h=
package com.adt.service; ZO+RE7f*?c
+a,SP
import net.sf.hibernate.HibernateException; {FJMcO=
vYgJu-Sl
import org.flyware.util.page.Page; _u]Z+H"
L]Tj]u)
import com.adt.bo.Result; V@'Xj .ze
*5'8jC"2g
/** 35h|?eN_m!
* @author Joa gtKih
*/ Kz'GAm\
publicinterface UserManager { pa-*&p
\f,<\mJ#
public Result listUser(Page page)throws pY&6p~\p
Yy~x`P'g!
HibernateException; 757&bH|a
s_^`t+5
} KOixFn1
G|cjI*
;~3;CijJ8
ys=2!P-[#
3M#x)cW
java代码: _L,~WYRo
(Mv~0ShakO
It*U"4lgi
/*Created on 2005-7-15*/
?K-4T
package com.adt.service.impl; Y3@+aA
Z~:)hwF
import java.util.List; ,[n9DPZ
FM]clC;X?
import net.sf.hibernate.HibernateException; 2)EqqX[D
Wvb ~j
import org.flyware.util.page.Page; _'p/8K5)=
import org.flyware.util.page.PageUtil; 4s{=/,f
l!1_~!{y
import com.adt.bo.Result; G}U <^]c
import com.adt.dao.UserDAO;
(N/u@ M
import com.adt.exception.ObjectNotFoundException; @tT`s^e
import com.adt.service.UserManager; W@!qp
%
jDH{xSMb
/** ^*jwe^
* @author Joa :1d;jx>
*/ ]ty$/{hx'
publicclass UserManagerImpl implements UserManager { %XR(K@V
=2q#- ,t
private UserDAO userDAO; :@(1~Hm
\: ZDY(>1
/** qt:B]#j@
* @param userDAO The userDAO to set. nLL2/!'n
*/ , S^y>
publicvoid setUserDAO(UserDAO userDAO){ Az8b_:=
this.userDAO = userDAO; l#uF%;GDX
}
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,wf_o%'eW
/* (non-Javadoc) p*K #s1
* @see com.adt.service.UserManager#listUser r'ilJ("
oW
OR7)?r
(org.flyware.util.page.Page) yR5XcPoKI
*/ 9z?c0W5x
public Result listUser(Page page)throws FM%WMyb[
a|TUH+|
HibernateException, ObjectNotFoundException { ZXLAX9|
int totalRecords = userDAO.getUserCount(); MoxWnJy}
if(totalRecords == 0) Q>[{9bI4QP
throw new ObjectNotFoundException 0~<?*{~
I!b"Rv=Nf-
("userNotExist"); qo:Zc`t(R
page = PageUtil.createPage(page, totalRecords); EFiVwH
List users = userDAO.getUserByPage(page); shGUG;
returnnew Result(page, users); 4~Q<LEly
} 5xT, O
xqdkc^b
} ipG 0ie+
5>dA7j^v
yl*%P3m|
=H: N!!:
0rX%z$D+@
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 AW;xlY= g
} A6z%|d
询,接下来编写UserDAO的代码: rhYAR r'
3. UserDAO 和 UserDAOImpl: E*R-Dno_F
java代码: g[y&GCKY!=
nzO-\`40
0^L:`[W+
/*Created on 2005-7-15*/ Rhlm
package com.adt.dao;
"X=^MGV
T&1-gswr:
import java.util.List; 7aRy])x
(7_ezWSl>
import org.flyware.util.page.Page; Tq^B>{S"
/_JR7BB^X,
import net.sf.hibernate.HibernateException; N f?\O@
6ImW|%
/** ^^V+0 l
* @author Joa Z3<lJk\Y
*/ W-D4"
G@
publicinterface UserDAO extends BaseDAO { Hl}m*9<9us
g\+!+!"~
publicList getUserByName(String name)throws 7h.[eMLPB
iyR5mA
HibernateException; g}?39?o4
8eCh5*_$
publicint getUserCount()throws HibernateException; amQiH!}8R
'mv|6Y
publicList getUserByPage(Page page)throws _x-2tnIxXv
D41.$t[
HibernateException; }WR@%)7ay
NUBzc'qb
} zzC{I@b
/^i_tLgb
YY>&R'3[
17:7w
?r$&O*;
java代码: T_\hhP~
=%77~q-HL
eHHU2^I,
/*Created on 2005-7-15*/ <e|B7<.
package com.adt.dao.impl; AgDXpaq
!~m PxGY
import java.util.List; wlwgYAD
\*fXPJ4
import org.flyware.util.page.Page; OK@yMGz1I
5n::]Q%=D
import net.sf.hibernate.HibernateException; M6[O>z
import net.sf.hibernate.Query; j<?k$8H
3E @ &
import com.adt.dao.UserDAO; [8b{Ybaz
s2tNQtq0W
/** HS.eK#:N
* @author Joa (6)|v S
*/ Rs'mk6+
public class UserDAOImpl extends BaseDAOHibernateImpl vN6)Szim
(^ J2(
implements UserDAO { 7*+tG7I @
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/* (non-Javadoc) U
d+6=Us{
* @see com.adt.dao.UserDAO#getUserByName U,<?]h
q)"yP\
(java.lang.String) M VE:JNm
*/ #E/|WT
publicList getUserByName(String name)throws +D h?MQt?
=4/K#cQ
HibernateException { %u?A>$Jn
String querySentence = "FROM user in class Mf9x=K9
w!UIz[ajI
com.adt.po.User WHERE user.name=:name"; 0b=00./o
Query query = getSession().createQuery 9WL$3z'*
Fp+fZU
(querySentence); On;7
query.setParameter("name", name); !'bZ|j%
return query.list(); >b*}Td~J
} :dlG:=.W
BE!WCDg,
/* (non-Javadoc) =1VpO{q
* @see com.adt.dao.UserDAO#getUserCount() )uCa]IR
*/ /7R0w
publicint getUserCount()throws HibernateException { 9 b&HqkXX
int count = 0; PmUq~YZ7
String querySentence = "SELECT count(*) FROM e=i9l
dY?>:ce
user in class com.adt.po.User"; 1mv8[^pF
Query query = getSession().createQuery /p{$HkVw
\NL*$SnxP
(querySentence); q] '2'"k
count = ((Integer)query.iterate().next !imjfkG
ZyrVv\'
()).intValue(); e1H2w?
s
return count; _ o6Zj1p
} ib(4Y%U6~
7]
>z e
/* (non-Javadoc) P.Qz>c^-C
* @see com.adt.dao.UserDAO#getUserByPage )9{!=k
D'
h%.
(org.flyware.util.page.Page) X$<CIZ
*/ kI~;'M
publicList getUserByPage(Page page)throws kznm$2 b
mN"g~o*
HibernateException {
{u$<-W-&
String querySentence = "FROM user in class \2[
qD(dAU
com.adt.po.User"; KhNE_.
Z
Query query = getSession().createQuery =nUzBL%~
;+~Phdy
(querySentence); 5Noy~;
query.setFirstResult(page.getBeginIndex()) j[$+hh3:
.setMaxResults(page.getEveryPage()); RAoY`AWI
return query.list(); q:P44`Aq
} rVb61$
}ho6
} ]L!:/k,=S
#PMi6q~Z
6P`!yBAu
CuYSvW
9t{Iv({6p
至此,一个完整的分页程序完成。前台的只需要调用 d?jzh1
^4
~ V/
userManager.listUser(page)即可得到一个Page对象和结果集对象 i=`@)E
Nj}-"R\u
的综合体,而传入的参数page对象则可以由前台传入,如果用 hx!hI1
aB~=WWLR\
webwork,甚至可以直接在配置文件中指定。 P?M WT]fY
Hg+bmwM
下面给出一个webwork调用示例: 8^qLGUxz
java代码: Dp;6CGYl?
oN.#q$\` k
RA:3ZV
/*Created on 2005-6-17*/ e8hwXz
package com.adt.action.user; >^adxXw.o
9y*pn|A[F
import java.util.List; cG4$)q;q
wGx*Xy1n<
import org.apache.commons.logging.Log; q4KYC!b
import org.apache.commons.logging.LogFactory; Z:<6Ck
import org.flyware.util.page.Page; ]= 9^wS
j.g9O]pi
import com.adt.bo.Result; 71k>_'fl
import com.adt.service.UserService; KqWt4{\8v`
import com.opensymphony.xwork.Action; w4;1 ('
b^&nr[DC
/** 2~!+EH
* @author Joa &&|c-mD+*
*/ QR[i9'`<
publicclass ListUser implementsAction{ \']_ y\
>?^_JEC6
privatestaticfinal Log logger = LogFactory.getLog Qr]`flQ8
=.6JvX<d1*
(ListUser.class); , n47.S
b,-qyJW6
private UserService userService;
W[oQp2 =
9>[*y8[:0
private Page page; cp3O$S
Aw7_diK^
privateList users; u*<knZ~ty
J+f*D+x1
/* G>j4b}e
* (non-Javadoc) DBZ^n9
* P(~vqo>!
* @see com.opensymphony.xwork.Action#execute() W4S! rU
*/ zr1A4%S"
publicString execute()throwsException{ *ta?7uSiT
Result result = userService.listUser(page); @SH$QUM(
page = result.getPage(); 7\ kixfEg
users = result.getContent(); gw v
s
return SUCCESS; Y
#6G&)M
} vC%8-;8{H
O",*N
/** "1>48Z-UC
* @return Returns the page. hd_<J]C
*/ FKk.BA957h
public Page getPage(){ nY 50dFA,
return page; "/$2oYNy+
} l5CFm8%
x10u?@
/** a X:,1^
* @return Returns the users. ^mCKRWOP'
*/ NVq3h\[X
publicList getUsers(){ %H8s_O
return users; u%I |o s]
} ynU20g
GilmJ2<
/** Kz2s{y~?
* @param page s|o+
Im
* The page to set. 4~mmP.c
*/ ^Qa!{9o[
publicvoid setPage(Page page){ nypG
this.page = page; f,'9Bj.~
} 1_6oM/?'
[mA\,ny9
/** y#)ad\
* @param users ?S~j2 J]
* The users to set. db5@+_
*/ )|`|Usn#[
publicvoid setUsers(List users){ M
Qlx&.>
this.users = users; @;ob 4sU
} }q D0-
T~-OC0
/** TjLW<D(i>
* @param userService Vs@H>97,G
* The userService to set. J0O wzO
*/ xty)*$C>
publicvoid setUserService(UserService userService){ w4(g]9^Q
this.userService = userService; I/ V`@*/+
} ;FO( mL (
} H&E3RU>`
^% jk. *
F%^)oQT+c
B"=w9w]
XCUU(H
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ^QTtCt^:
TIYo&?Z)
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 jltW@co2sV
Y;[+ ^J*a
么只需要: vvmG46IgZ
java代码: 6Us*zKgW
,)%$Zxng
vG'I|OWg
<?xml version="1.0"?> b&\f 8xZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {'$+?V"&
rs+
["h
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q>Kzl/~c.P
Hh{pp ^
1.0.dtd"> t?;\'
Dwg_#GSr
<xwork> \:D"#s%x
u;3wg`e
<package name="user" extends="webwork- )0N^rw kW
A#KfG1K>
interceptors"> %8$ldNhV
q3}WO]TBj
<!-- The default interceptor stack name ~1.B
fOR8
cPbAR'
--> ?3Y~q;I]O
<default-interceptor-ref EEdU\9DH(
SKeX~uLz
name="myDefaultWebStack"/> w$4*/D}Y
{dXmSuO
<action name="listUser" }(/\vTn*1
g=L80$1
class="com.adt.action.user.ListUser"> (,OF<<OH
<param 3+oGR5gIN
pRH'>}rtuH
name="page.everyPage">10</param> =u
3YRqz
<result !@4 i:,p@
W|4h;[w
name="success">/user/user_list.jsp</result> 28x:]5=jb
</action> Y=\:fa
KuJNKuHa.
</package> :jr`}Z%;y
+Hkr\
</xwork> 5Vj O:>
8"yZS)09
Wf:LYL
pX?/=T@ Bw
)zK@@E
9>T5~C'*
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 P87Lo4Rd
Q.} guI\
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 fprP$MbI
ae0t*;~
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 (d>}Fp
DVz_;m6)
p-XO4Pc6
L25%KGg'o
)18C(V-x
我写的一个用于分页的类,用了泛型了,hoho ToX--w4
Jp"yb`w
java代码: o1Nfn'!3/>
LDh,!5G-M
}*?,&9/_)
package com.intokr.util; Fxv5kho
W[<ZI>mf
import java.util.List; 3nnoXc'
s`gfz}/
/** <rxtdI"3
* 用于分页的类<br> ve^gzE$<I
* 可以用于传递查询的结果也可以用于传送查询的参数<br> zvK'j"Wq=
* D`R~d;U~
* @version 0.01 SFR<T
* @author cheng ;cfPS
*/ IxaF*4JG
public class Paginator<E> { u~7fK
privateint count = 0; // 总记录数 E<sd\~~A:
privateint p = 1; // 页编号 JA~q}C7A7o
privateint num = 20; // 每页的记录数 Lu
CiO
privateList<E> results = null; // 结果 X^Fc^U8
?&?5x%|.<
/** qs!A)H#
* 结果总数 i2+_~$f
*/ -G(#,rXk
publicint getCount(){ n?*r, )'
return count; d9up!
k
} QJ +Ml
X& mD/1
publicvoid setCount(int count){ H3LuRGe&2
this.count = count; b|e1HCH
} 9,[AfI
|y
pXO3
/** <$??Z;6
* 本结果所在的页码,从1开始 7n,=`0{r
* Y_)xytJ$
* @return Returns the pageNo. +U)4V}S)
*/ M+*K-zt0
publicint getP(){ W*B=j[w
return p; ;Z); k`j
} {2 k]$|
//'&a-%$^
/** +xd@un[r<
* if(p<=0) p=1 'xLXj>
* RsYMw3)G
* @param p S)?N6sz%
*/ E0AbVa.
publicvoid setP(int p){ vXm'ARj
if(p <= 0)
ne:
'aq
p = 1; td7Of(k'
this.p = p; &0i$Y\g
} Fw:_O2
e07u@_'^
/** >gDeuye
* 每页记录数量 WLA&K]
*/ q@g#DP+C
publicint getNum(){ Dt!
<
return num; (eAz
nTU
} ~ #7@;C<nt
8@Bm2?$}g
/** &(lQgi+^!
* if(num<1) num=1 F^Bk @
*/ v: veKA
publicvoid setNum(int num){ yf7|/M
if(num < 1) Mh{244|o[
num = 1; 5'( T*"
this.num = num; ut#pg+#Q
} 70'gVCb
Zrp-Hv27,,
/** 2Z5_@Y
* 获得总页数 4jSYR#Hqp`
*/ c8Q}m(bhWI
publicint getPageNum(){ JfY(};&
return(count - 1) / num + 1; Ot)S\s>
} *nYg-)
|]9L#
/** g)R 2V
* 获得本页的开始编号,为 (p-1)*num+1 cK >^8T^
*/ BeN]D
publicint getStart(){ F{.\i *$
return(p - 1) * num + 1; I&m' a
} yM7Iq)o6u
=H3tkMoi2
/** ;>L8&m)R5
* @return Returns the results. :Nv7Wt!
*/ |j81?4<)v
publicList<E> getResults(){ +g kJrw
return results; TEh.?
} G |[{\
(^(l=EN-<
public void setResults(List<E> results){ zhm 0J-g
this.results = results; c#>(8#'.U
} r@m]#4
L~^5Ez6U
public String toString(){ Sb> &m
StringBuilder buff = new StringBuilder Ix}6%2\
co3\1[q"b
();
)UM^#<-
buff.append("{"); <e?Eva%t`
buff.append("count:").append(count); ^!d0abA
buff.append(",p:").append(p); ~!!\#IX
buff.append(",nump:").append(num); \xbUr`WBY
buff.append(",results:").append ,oh;(|=
2,F9P+
(results); XL^05
buff.append("}"); jS~Pdz
return buff.toString(); pmvd%X\f
} (S?Y3l|
QxdC[t$Lp
} ~r!(V;k{
(/N&_r4x
"I)zi]vk