Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }n:?7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 g`^X#-!(
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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 n"Veem[_4g
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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 /UcV
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分页支持类: ZzGahtx)Y
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java代码: )::>q5c
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package com.javaeye.common.util; BimjQ;jtI
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import java.util.List; URgk^nt2p
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publicclass PaginationSupport { 6Q&r0>^{
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publicfinalstaticint PAGESIZE = 30; \2-@' ^i
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privateint pageSize = PAGESIZE; Vgb *% I
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privateList items; 9I7\D8r
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privateint totalCount; o Pci66
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privateint[] indexes = newint[0]; C;+(Zp
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privateint startIndex = 0; ^)!F9h+
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public PaginationSupport(List items, int /PBaIoJE
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totalCount){ j1 q[2'
setPageSize(PAGESIZE); s.Y4pWd5@
setTotalCount(totalCount); =;a!u
setItems(items); Di_2Plo)4
setStartIndex(0); 7tM9u5FF
} sZWaV4
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public PaginationSupport(List items, int B$3 ?K
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totalCount, int startIndex){ sxKf&p;
setPageSize(PAGESIZE); ?^mi3VM
setTotalCount(totalCount); [H\:pP8t
setItems(items); 54;J8XT7
setStartIndex(startIndex); AE`We$!
} X[s8X!#
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public PaginationSupport(List items, int b !@Sn/
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totalCount, int pageSize, int startIndex){ G|w=ez
setPageSize(pageSize); keW~ NM
setTotalCount(totalCount); PP~rn fE
setItems(items); 0_P}z3(M
setStartIndex(startIndex); anw}w!@U
} #PDf,^
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publicList getItems(){ )0vU
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return items; _\PNr.D8
} o}Odw;
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publicvoid setItems(List items){ PjT=$]
this.items = items; 1(zsOeX
} H7Uli]e3
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publicint getPageSize(){ E9|eu\
return pageSize; n,HE0Zn]Y_
} ,/&'m13b/L
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publicvoid setPageSize(int pageSize){ ECdvX0*a
this.pageSize = pageSize; 1aVa0q<
} J`q]6qf#
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publicint getTotalCount(){ \l"&A
return totalCount; \$aF&r<R
} 9`jcC-;iv
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publicvoid setTotalCount(int totalCount){ RCTQhTy=
if(totalCount > 0){ J89Dul l
this.totalCount = totalCount; @~<j&FTT
int count = totalCount / &
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pageSize; =1I#f
if(totalCount % pageSize > 0) (>6*#9#p
count++; +x9cT G
indexes = newint[count]; {e|*01hE
for(int i = 0; i < count; i++){ .6O"|
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indexes = pageSize * uPYmHA}_/
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i; q#Zs\PD
} W"{v2x i
}else{ QB:i/9
this.totalCount = 0; #po5_dE\*
} lf>*Y.!@me
} =.]l*6WV
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publicint[] getIndexes(){ RsU3Gi_Zdz
return indexes; kt[:@Nda9
} I/VxZ8T
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publicvoid setIndexes(int[] indexes){ P o jmC
this.indexes = indexes; E^GHVt/.
} Tmh(=
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publicint getStartIndex(){ 87}&`
return startIndex; I -Xlx<
} 6:U$w7P0
e
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publicvoid setStartIndex(int startIndex){ AC
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if(totalCount <= 0) GV)<Q^9
this.startIndex = 0; sS&Z ,A
elseif(startIndex >= totalCount) KbL V'%D
this.startIndex = indexes jENr>$$
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[indexes.length - 1]; M3p
elseif(startIndex < 0) #-3=o6DCK
this.startIndex = 0; "'g[1Li
else{ J};z85B
this.startIndex = indexes HL/bS/KX
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[startIndex / pageSize]; Om M=o*d
} LG~S8u
} JKer//ng4
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publicint getNextIndex(){ f<+4rHT
int nextIndex = getStartIndex() + bX.ja;;
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pageSize; $Vc~/>
if(nextIndex >= totalCount) iv phlw
return getStartIndex(); n~g)I&
else !-m&U4Ku6o
return nextIndex; #j@71]GI
} V{|}}b?w?
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publicint getPreviousIndex(){ :Rs^0F8)c
int previousIndex = getStartIndex() - "MIq.@8ra
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pageSize; 5XuT={o
if(previousIndex < 0) ,>t69 Ad
return0; \#68;)+=
else _k^0m
return previousIndex; Q]rD}Ckv-
} >5R<;#8
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} _U;eN|Ww
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抽象业务类 >3awn*N
java代码: :'aAZegQY
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/** 8/z3=O&
* Created on 2005-7-12 `mye}L2I
*/ CG'.:`t
package com.javaeye.common.business; xEuN
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import java.io.Serializable; `%3/
import java.util.List; q1E:l!2al
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import org.hibernate.Criteria; 0Z|FZGRP
import org.hibernate.HibernateException; pZ#ap<|>I
import org.hibernate.Session; v/ *Y#(X
import org.hibernate.criterion.DetachedCriteria; A:<;M@q!
import org.hibernate.criterion.Projections; X=8Y%
import yL;M"L
#YDr%>j
org.springframework.orm.hibernate3.HibernateCallback; UpXz&k
import \7"@RHcihB
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org.springframework.orm.hibernate3.support.HibernateDaoS ~2EH OO{
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upport; Tz2-Bp]h
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import com.javaeye.common.util.PaginationSupport; OT^%3:zg
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public abstract class AbstractManager extends 6Es?
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HibernateDaoSupport { y2O4I'/5<
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privateboolean cacheQueries = false; 2xw6 5z
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privateString queryCacheRegion; fF*`'i=!
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publicvoid setCacheQueries(boolean &R~n>>c
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cacheQueries){ G8W#<1LE
this.cacheQueries = cacheQueries; RtG}h[k/X
} "U.^lkN
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publicvoid setQueryCacheRegion(String &'l>rD^o
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queryCacheRegion){ K/ &?VIi`z
this.queryCacheRegion = ND<!4!R^
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queryCacheRegion; @pGZLq
} 7FN<iI&7\
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publicvoid save(finalObject entity){ gn5)SP 8
getHibernateTemplate().save(entity); K;7f?52
} A?TBtAe
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publicvoid persist(finalObject entity){ W)(^m},*8D
getHibernateTemplate().save(entity); xf%4, JQ
} }FF W|f
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publicvoid update(finalObject entity){ F_xbwa*=
getHibernateTemplate().update(entity); #S%Q*k<hw
} y]%w )4PS
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publicvoid delete(finalObject entity){ 6.t',LTB
getHibernateTemplate().delete(entity); I2(zxq&2M\
} :a:[.
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publicObject load(finalClass entity, V8=Y@T,
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finalSerializable id){ D71;&G]0
return getHibernateTemplate().load (h']a!
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(entity, id); `P Xz
} w@2Vts
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publicObject get(finalClass entity, (I@bkMp
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finalSerializable id){ ZxGP/D
return getHibernateTemplate().get = sAn,ri
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(entity, id); 2tayP@$
} lq.Te,Y%w
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publicList findAll(finalClass entity){ hzI*{
return getHibernateTemplate().find("from )o!XWh
5=(c%
" + entity.getName()); O7']
} @{h?+
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publicList findByNamedQuery(finalString 79zJ\B_
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namedQuery){ \qi|Js*{
return getHibernateTemplate ]E3U
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().findByNamedQuery(namedQuery); m?s}QGSka
} bg|!'1bD`5
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publicList findByNamedQuery(finalString query, F#xa`*AP
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finalObject parameter){ Y}6n]n;uR
return getHibernateTemplate }awzO#
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().findByNamedQuery(query, parameter); (3\Xy
} r!}al5~&
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publicList findByNamedQuery(finalString query, H* !EP
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finalObject[] parameters){ A5#y?Aq
return getHibernateTemplate 6VD1cb\lF
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().findByNamedQuery(query, parameters); 9ykM3
} lC97_T
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publicList find(finalString query){ /E wGW
return getHibernateTemplate().find `,wu}F85
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(query); %Qn(rA@9
} i5hD#
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publicList find(finalString query, finalObject {TXOQ>gY
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parameter){ B68H&h]D#'
return getHibernateTemplate().find 3l!NG=R
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(query, parameter); >=ot8%.!,B
} 5IVksg
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public PaginationSupport findPageByCriteria lD;'tqaC
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(final DetachedCriteria detachedCriteria){ #i QX6WF
return findPageByCriteria B\j~)vg
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); h
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} a7H0!9^h
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public PaginationSupport findPageByCriteria s #:%x#
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(final DetachedCriteria detachedCriteria, finalint >AD=31lq
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startIndex){ ed~R>F>
return findPageByCriteria &ju-
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(detachedCriteria, PaginationSupport.PAGESIZE, M\/XP| 7
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startIndex); y93k_iq$S
} U/MFhD(06
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public PaginationSupport findPageByCriteria q/@dR{-
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(final DetachedCriteria detachedCriteria, finalint Qb^q+C)o]
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pageSize, (4~WWU (iT
finalint startIndex){ v<rF'D2
return(PaginationSupport) L0Vgo<A
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getHibernateTemplate().execute(new HibernateCallback(){ =7[)'
publicObject doInHibernate vM0_>1nN
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(Session session)throws HibernateException { <3
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Criteria criteria = $7gB_o$zz
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detachedCriteria.getExecutableCriteria(session); Uf,fX/:!
int totalCount = J2Et-Cz 1
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((Integer) criteria.setProjection(Projections.rowCount H~+xB1
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()).uniqueResult()).intValue(); vx 0UoKX
criteria.setProjection go|>o5!g
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(null); UKB_Yy^Y
List items = P15:,9D
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criteria.setFirstResult(startIndex).setMaxResults p,#6
@*
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(pageSize).list(); ^KHLBSc:
PaginationSupport ps = -Q[g/%
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new PaginationSupport(items, totalCount, pageSize, mVf.sA8
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startIndex); 1 tfYsg=O
return ps; Ygj6(2
} l)}t,!M6
}, true); e9@(/+
} R8sck)k'}
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public List findAllByCriteria(final a+(j?_FyI
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DetachedCriteria detachedCriteria){ T&}Ye\%
return(List) getHibernateTemplate V:^H4WvL\W
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().execute(new HibernateCallback(){ u^Sv#K X
publicObject doInHibernate }""p)Y&
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(Session session)throws HibernateException { 8=H\?4)()Y
Criteria criteria = O k(47nC
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detachedCriteria.getExecutableCriteria(session); 3z,2utH
return criteria.list(); mCk5B*Jy
} nk08>veG
}, true); (KF7zP
} "\T"VS^pd
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public int getCountByCriteria(final "@t-Cy:!O
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DetachedCriteria detachedCriteria){ y_%&]/%
Integer count = (Integer) h;Mu[`
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getHibernateTemplate().execute(new HibernateCallback(){ QWhp:]}
publicObject doInHibernate uB+9dQ
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(Session session)throws HibernateException { D0%FELG05
Criteria criteria = 0VG=?dq
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detachedCriteria.getExecutableCriteria(session); Q;gQfr"c7
return 5ZsDgOeY
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criteria.setProjection(Projections.rowCount m!!;/e?yx
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()).uniqueResult(); &t[|%c*D&
} &wGg6$
}, true); rt;gC[3\
return count.intValue(); g\J)= ,ju,
} )+B=z}:Nfz
} vahf]2jEB
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用户在web层构造查询条件detachedCriteria,和可选的 ?'LM7RE$X6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7-g^2sa'(
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PaginationSupport的实例ps。 n2;(1qr
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ps.getItems()得到已分页好的结果集 VD4S_qx
ps.getIndexes()得到分页索引的数组 yA0Y
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ps.getTotalCount()得到总结果数 E 8^sy*f
ps.getStartIndex()当前分页索引 G;9|%yvd8
ps.getNextIndex()下一页索引 {.#j1r4J`
ps.getPreviousIndex()上一页索引 !G>(j
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 xO gq-@`
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 a[JZ5D
5~-}}F
一下代码重构了。 YiBOi?h9
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我把原本我的做法也提供出来供大家讨论吧: @2|G|C/]O}
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首先,为了实现分页查询,我封装了一个Page类: &0i71!Oy
java代码: * T\>
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/*Created on 2005-4-14*/ &
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package org.flyware.util.page; -YAO3
n4XMN\:g{
/** ?9,YVylg
* @author Joa jUZ[`f;
* |y'b217t
*/ u4C1W|x
publicclass Page { FcY$k%;'Q
l [x%I
/** imply if the page has previous page */ &LwJ'h+nd
privateboolean hasPrePage; @u<0_r
t
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/** imply if the page has next page */ .0KOnLdK
privateboolean hasNextPage; kU>#1He
k\%,xf; x
/** the number of every page */ &7lk2Q\
privateint everyPage; {MA@A5
=cknE=
/** the total page number */ m_~y
privateint totalPage; 9PWm@
Nlf
@gY'YA8m
/** the number of current page */ EqYz,%I%
privateint currentPage; 0.3^
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/** the begin index of the records by the current !HbqbS22
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query */ C!`>cUhE{
privateint beginIndex; <&*#famX
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/** The default constructor */ o<~-k,{5P
public Page(){ m*OLoZVy
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} 55(J&q
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/** construct the page by everyPage ]9dx3<2_I
* @param everyPage t4C<#nfo
* */ <[esA9.]t
public Page(int everyPage){ G!-7ic_4
this.everyPage = everyPage; Hs.6;|0%
} p`pg5R
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/** The whole constructor */ |2[S/8g!
public Page(boolean hasPrePage, boolean hasNextPage, )Fw
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int everyPage, int totalPage, Q|6Ls$'$
int currentPage, int beginIndex){ =I
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this.hasPrePage = hasPrePage; fpI;`s
this.hasNextPage = hasNextPage; >2FAi.,
this.everyPage = everyPage; +.XZK3
this.totalPage = totalPage; Ks9FnDm8
this.currentPage = currentPage; #_JA5W+E
this.beginIndex = beginIndex; Qd9-u)L<
} 6@*5!,
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/** cH+h=E=
* @return .G7]&5s
* Returns the beginIndex. &?}kL=
h
*/ 5B8V$ X
publicint getBeginIndex(){ NKupOJJq
return beginIndex; dcV,_
} {d&X/tT
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/** nNd`]F^U
* @param beginIndex j;$6F/g
* The beginIndex to set. ]J8KCjq@
*/ G5y]^P
publicvoid setBeginIndex(int beginIndex){ a3b2nAI l
this.beginIndex = beginIndex; u^j8
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} ^D%}V- "
*#ob5TBq[
/** 4r68`<mn[
* @return 6M
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* Returns the currentPage. 3ybK6!g`[
*/ @&!=m]D*
publicint getCurrentPage(){ U)O?|
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return currentPage; Gp?ToS2^d
} Z%, \+tRe
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/** JL}hOBqfI
* @param currentPage {mCKTyN+
* The currentPage to set. +#de8/x
*/ 8MYLXW6
publicvoid setCurrentPage(int currentPage){ e;&{50VY
this.currentPage = currentPage; CVyx lc>
} =F",D=
f}Ne8]U/Hc
/** s9ju/+fv
* @return f.U0E6-(3N
* Returns the everyPage. z'vdC
*/ Tx|SAa=V
publicint getEveryPage(){ s$SU
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return everyPage; XvfcPI6
} 7eaA]y~H
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/** >
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* @param everyPage #;qFPj- v
* The everyPage to set. doxdRYKL
*/ P3,Z5|)
publicvoid setEveryPage(int everyPage){ ;PP_3`
this.everyPage = everyPage; Ak%no3:9
} P;HVL flu
CP F>^Mp#
/** +SZ%&
* @return }"g21-T^
* Returns the hasNextPage. i?&4SG+2~K
*/ rzYobOKd#
publicboolean getHasNextPage(){ XudH
return hasNextPage; FcA)RsMI*
} Qwp\)jVi
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/** 1`2);b{@
* @param hasNextPage rE
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* The hasNextPage to set. hB2s$QS
*/ iECC@g@a
publicvoid setHasNextPage(boolean hasNextPage){ q>D4ma^
this.hasNextPage = hasNextPage; &F<J#cfe8
} " kE:T.,
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/** 1{\,5U&
* @return BM=V,BZy
* Returns the hasPrePage. P0`>{!r6@
*/ QXIbFv
publicboolean getHasPrePage(){ Xj})?{FP
return hasPrePage; X1
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} )$lSG}WD
@Le ^- v4
/** ~q'w),bE"Q
* @param hasPrePage t9$AvE#a!=
* The hasPrePage to set. ]sm0E@ 1
*/ Y7b,td1
publicvoid setHasPrePage(boolean hasPrePage){ ;S{Ld1;
this.hasPrePage = hasPrePage; (TbB?X}
} \U<F\i
k
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/** Vx\#+)4
* @return Returns the totalPage. C,VqT6E<
* O_s9
*/ b Q9"GO<X
publicint getTotalPage(){ Us@ {w`T
return totalPage; [X$|dOm'N
} 1=/MT#d^?
xRTg
[
/** vBCZ/F[
* @param totalPage +*:x#$phx
* The totalPage to set. !Wdt:MUI8
*/ ]X"i~$T1 S
publicvoid setTotalPage(int totalPage){ L[QI 5N
this.totalPage = totalPage; "ojD f3@{
} x=)30y3*;
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} yoA*\V
-;/@;W
A
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 x`=5l`
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个PageUtil,负责对Page对象进行构造: D\_*,Fc
java代码: ;2xXX,'R7
L2/<+Zw
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/*Created on 2005-4-14*/ K9z_=c+
package org.flyware.util.page; r/s&ee
|V~(mS747:
import org.apache.commons.logging.Log; 6!Tf'#TV~!
import org.apache.commons.logging.LogFactory; Lct+cKKU
6_`eTL=G
/** qS/71Kv'
* @author Joa ?+} E
* GD6'R"tJ
*/ <g|nmu)o$
publicclass PageUtil { 9 (FcA5Y
qdkTg: QJ,
privatestaticfinal Log logger = LogFactory.getLog M;Mdz[Q
Bc9|rl V,
(PageUtil.class); xUYN\Pc-
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/** h?pGw1Q
* Use the origin page to create a new page 2sd=G'7!
* @param page b09#+CH?
* @param totalRecords |\r\i&|g1
* @return r^o}Y
*/ as!|8JE`
publicstatic Page createPage(Page page, int I`n1M+=%
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totalRecords){ EBn:[2
return createPage(page.getEveryPage(), ?H7p6mu
?;.+A4
page.getCurrentPage(), totalRecords); dE9aE# o
} {*=5qV}
C7*Yg$`{
/** 2QuypVC ]
* the basic page utils not including exception G3?a~n^b
s)7`r6w
handler )dN,b(w9
* @param everyPage 8KdcLN@
* @param currentPage d7-F&!sQ
* @param totalRecords aid)q&AcQ
* @return page Ad N=y8T
*/ @ :
publicstatic Page createPage(int everyPage, int C`1\$U~%
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currentPage, int totalRecords){ 4#Nd;gM2
everyPage = getEveryPage(everyPage); {Z~VO
currentPage = getCurrentPage(currentPage); 9787uj]Y}H
int beginIndex = getBeginIndex(everyPage, %!hA\S
7QL) }b.H
currentPage); >5@ 0lYhH
int totalPage = getTotalPage(everyPage, fO}1(%}d
r Xk
totalRecords); +iDz+3v(
boolean hasNextPage = hasNextPage(currentPage, 8#JyK+NU
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totalPage); >8HRnCyp/
boolean hasPrePage = hasPrePage(currentPage); +w}%gps
(S93 %ii
returnnew Page(hasPrePage, hasNextPage, Z YO/'YW
everyPage, totalPage, P*^UU\x'4I
currentPage, B(vz$QE,$r
HvfTC<+H
beginIndex); PT*@#:MA
} +z/73s0~
rN!9&
privatestaticint getEveryPage(int everyPage){ UtW3KvJ#=
return everyPage == 0 ? 10 : everyPage; GISI8W^
} 6 VJj(9%
,4I6Rw B.
privatestaticint getCurrentPage(int currentPage){ l[j0(T
return currentPage == 0 ? 1 : currentPage; AE@Rn(1.
} T=KrT7
NZ? =pfK\s
privatestaticint getBeginIndex(int everyPage, int RoXOGVo
r3lr`s`
currentPage){ #S74C*'8
return(currentPage - 1) * everyPage; 2OOj8JS
} y]z# ??
B!C32~[
privatestaticint getTotalPage(int everyPage, int
nLLHggNAV
C4d1*IQk
totalRecords){ i*rv_G|(Zj
int totalPage = 0; +( 7vmC.
'$ nGtB5
if(totalRecords % everyPage == 0) -kS5mR
totalPage = totalRecords / everyPage; T//+&Sk[
else /]58:euR
totalPage = totalRecords / everyPage + 1 ; G!lykk]
/u1zRw
return totalPage; GnHf9
JrR
} W$ {sD|d-
BHBR_7
privatestaticboolean hasPrePage(int currentPage){ n6+MqN
return currentPage == 1 ? false : true; 8pKPbi;(2
} !Dn1pjxc
|&*rSp2iH
privatestaticboolean hasNextPage(int currentPage, _5 -"<
;Cpm3at
int totalPage){ yq^$H^_O
p
return currentPage == totalPage || totalPage == ^*>no=A
[9Hm][|Ph
0 ? false : true; fC:\Gh5
} f*f9:xUY
UE](`|4H
&%51jM<
} A)0m~+?{J
'n`$c{N<tM
,
Vr6
w0OK.fj
"[Lp-4A\
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。 C3Z(k}
~oyPmIcb
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 nr6[rq
BU .G~0
做法如下: rMx_ <tX X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1KEPD@0oxx
|-?b)yuAz
的信息,和一个结果集List: 6/C
java代码: jDR\#cGrZ
k.hSN8
ZACn_gd[5
/*Created on 2005-6-13*/ g9`ytWmM
package com.adt.bo; v<4X;4p^
'Pn`V{a
import java.util.List; 6H9]]Unju
,*#M%Pv1t
import org.flyware.util.page.Page; ZuON@ (
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/** 0
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* @author Joa ?Io2lFvI@Y
*/ L3Iz]D3s
publicclass Result { {=Y&q~:8v
qTex\qP
private Page page; mQ)l`wGh
#@`^
.
private List content; aesFv)5DK
BF#e=p
/** |8rJqtf +&
* The default constructor Y`Rf E
*/ @T T[H*,
public Result(){ jV8><5C
super(); iSax-Mc
} b(,[g>xH
q3:'
69
/** m/h0J03'T
* The constructor using fields *GMRu,u2
* e$h\7i:(
* @param page 1A
*8Jnw
* @param content 3sNq3I
*/ "*WXr$
public Result(Page page, List content){ 1Sr}2@>
this.page = page; HyMb-Us
this.content = content; sJvn#cS
} `_
L|Is=n
7u(i4O&
k
/** &ICO{#v5
* @return Returns the content. lDXH<W?
*/ 2HNS|GHb&
publicList getContent(){ &c!-C_L 2
return content; {,-# ;A*yW
} >skS`/6
wm4e:&
/** .YlM'E*X
* @return Returns the page. K ajyQ"j
*/ U9s y]7
public Page getPage(){ S]a$w5ZP
return page; &!Vp'l\9
} YWdvL3Bgk,
W_EN4p~J
/** z@j&vW
* @param content }8e%s;C
* The content to set. lX7^LB
*/ &3. 8i%
public void setContent(List content){ :'=C/AL
this.content = content; i=UJ*c
} }mK_d9d x
4#uoPkLK
/** o%iTYR:x
* @param page !{LwX Kf
* The page to set. PGDlSB^O
*/ R&A.F+Zgt
publicvoid setPage(Page page){ b/`'?|
C
this.page = page; j|9 2
g
} I1jF`xQ&0
} Q[^d{e*l
bx>D
"M]]H^r5
`pr,lL
Z$@Nzza-
2. 编写业务逻辑接口,并实现它(UserManager, U# gmk0>t{
Zuf&maa S
UserManagerImpl) 4a~_hkY]
java代码: +{Ttv7l_2
,q1RJiR
gB#t"s)
/*Created on 2005-7-15*/ :KwYuwYS
package com.adt.service; i|e-N?l
g=wnly
import net.sf.hibernate.HibernateException; LvaF4Y2v
-q27N^A0
import org.flyware.util.page.Page; Ym6[~=~EK
|BR&p)7)
import com.adt.bo.Result; ~yV0SpL
[LK
9^/V
/** 3yDvr*8-@
* @author Joa j<u`W|vl
*/ _'Z@ < ,L
publicinterface UserManager { f32nO
S6uBk"V!
public Result listUser(Page page)throws lK0coj1+
coBxZyM 1}
HibernateException; 2_p/1Rs
"#%T*c{Tf0
} |ONOF
}N NyUwFa
tQ"PCm
,h"M{W$
Q6E80>
java代码: 4U3T..wA
d?JVB
1x]G/I*
/*Created on 2005-7-15*/ {.AFg/Z
package com.adt.service.impl; 6aL`^^
dJk.J9Z
import java.util.List; hk(^?Fp
HDYoM
import net.sf.hibernate.HibernateException; PeOgXg)L`z
@U,cj>K
import org.flyware.util.page.Page; \VW.>@s~
import org.flyware.util.page.PageUtil; \%#jT GFs~
^(y4]yZ
import com.adt.bo.Result; U}NNbGQj
import com.adt.dao.UserDAO; lxbZM9A2
import com.adt.exception.ObjectNotFoundException; q;+qIV&.:
import com.adt.service.UserManager; 1-`8v[S
|dvcDx0|K
/** D*b>
l_
* @author Joa xJ4T7 )*
*/ iVA_a8}
publicclass UserManagerImpl implements UserManager { k~R_Pq
S
JP#m}W
private UserDAO userDAO; n']@Spm
,+XQ!y%
/** vjW S35i
* @param userDAO The userDAO to set. XS>4efCJ
*/ J?{uG8)
publicvoid setUserDAO(UserDAO userDAO){ ?U&onGy
this.userDAO = userDAO; mY-r:
} l`d=sOB^
9,4a?.*4~
/* (non-Javadoc) Bi]%bl>%
* @see com.adt.service.UserManager#listUser iC
2:P~
g\2Y605DM
(org.flyware.util.page.Page) GerZA#
*/ 0=~Ji_5mB
public Result listUser(Page page)throws H&I0\upd
R6ywc"xE
HibernateException, ObjectNotFoundException { ~&g:7f|X
int totalRecords = userDAO.getUserCount(); D+RG,8Ht
if(totalRecords == 0) W /IyF){
throw new ObjectNotFoundException 8<xJmcTEwO
3+IS7ATn
("userNotExist"); ~{xY{qL
page = PageUtil.createPage(page, totalRecords); C0e<
_6p=
List users = userDAO.getUserByPage(page); ~yci2{
returnnew Result(page, users); cOIshT1
} O*CKyW_$t
[qc90)^Q,
} wEk9(|
/#blXI
p<
XjiRq
OA[w|Tt
.iw+#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :[Fwc
)V3G~p=0
询,接下来编写UserDAO的代码: kIQMIL0+
3. UserDAO 和 UserDAOImpl: Xf:-K(%e
java代码: bBGLf)fsTG
t1xX B^.M{
Fm:Ri$iT
/*Created on 2005-7-15*/ P'zA=Rd&~>
package com.adt.dao; 97Whn*
iYFM@ta
import java.util.List; +3VY0J
e<q;` H
import org.flyware.util.page.Page; %ePInpb
F&Q:1`y
import net.sf.hibernate.HibernateException; R6!t2gdKe@
&}6=V+J;
/** ;vuok]@
* @author Joa I6\l6 o
*/ 6*CvRb&
publicinterface UserDAO extends BaseDAO { s3oK[:/
!s5 _JO
publicList getUserByName(String name)throws :Z,zWk1|
1--5ok
h
HibernateException; Rzw}W7zg[
~|riFp=J
publicint getUserCount()throws HibernateException; 0&zp9(G5
ZjbMk3Y
publicList getUserByPage(Page page)throws h%Bp%Y9
)%P!<|s:5
HibernateException; ZfoI7<?33
&!_>J0
} (|<}q-wO
G3m+E;o1
zGA#7W2?0
Ak&eGd$d
z;D[7tT
java代码: DdPU\ ZWR
Lk4gjs,V
~#Vrf0w/
/*Created on 2005-7-15*/ ;=aj)lemCr
package com.adt.dao.impl; _A1r6
1#6c
sZW5
import java.util.List; :D;BA
EQ\/I(
=l
import org.flyware.util.page.Page; =56O-l7T*w
n}0[EE!
import net.sf.hibernate.HibernateException; 5!-'~W
import net.sf.hibernate.Query; w_PnEJa9
^_n(>$
EK
import com.adt.dao.UserDAO; B/AS|i] sM
>,7-cm=.
/** ,x&T8o/a
* @author Joa #,lJ>mTe4
*/ [s"xOP9R
public class UserDAOImpl extends BaseDAOHibernateImpl AfB,`l`k
s&TPG0W
implements UserDAO { AKu]c-
*7FtEk/l
/* (non-Javadoc) Gu-6~^Km9
* @see com.adt.dao.UserDAO#getUserByName W:'H&`0
G*JasHFs
(java.lang.String) ^,*!Qk<c
*/ BRyrdt*_e
publicList getUserByName(String name)throws tP^2NTs%]
Z0 @P1
HibernateException { S8 .1%sw
String querySentence = "FROM user in class yp9vgUs
n Hz Xp:"
com.adt.po.User WHERE user.name=:name"; imC>T!-7
Query query = getSession().createQuery I82GZL
dv1Y2[
(querySentence); M8(N9)N
query.setParameter("name", name); [`2V!rU
return query.list(); hR(\ %p
} Y,n&g45m
E9<oA.
/* (non-Javadoc) 4c0 =\v
* @see com.adt.dao.UserDAO#getUserCount() {Dup k0'(
*/ k nTCX
publicint getUserCount()throws HibernateException { %OE
(?~dq
int count = 0; N3"O#C
String querySentence = "SELECT count(*) FROM Vq4g#PcG
3qggdi
user in class com.adt.po.User"; %m )vQ\Vtx
Query query = getSession().createQuery '(fQtQ%
'ioX,KD
(querySentence); UXgeL2`;
count = ((Integer)query.iterate().next 2D;2QdO
RA^6c![
()).intValue(); yzWVUqtXm
return count; 3e,"B
S)+
} F}MjZZj(U=
29z$z$l4
/* (non-Javadoc) E &G]R!
* @see com.adt.dao.UserDAO#getUserByPage dT?mMTKn+
"!,)Pv
(org.flyware.util.page.Page) #|-i*2@oR
*/ As"%
u
publicList getUserByPage(Page page)throws VYG o;
4fSGc8
HibernateException { s`#g<_ {X
String querySentence = "FROM user in class (_IP z)F
Z@(m.&ZRx
com.adt.po.User"; ((Uw[8#2`
Query query = getSession().createQuery 7fE U5@
;V v.$mI
(querySentence); 'nJ,mZx
query.setFirstResult(page.getBeginIndex()) a1#",%{I
.setMaxResults(page.getEveryPage()); *E.uqu>I
return query.list(); b@X+vW{S
} ?hBj q
erlg\-H
} YUjKOPN
yd|ao\'=
N.'-9hv
D4Z7j\3a
C:r3z50
至此,一个完整的分页程序完成。前台的只需要调用 zt!)7HBo
=W[M=_0u
userManager.listUser(page)即可得到一个Page对象和结果集对象 JIatRc?g
!(A<
的综合体,而传入的参数page对象则可以由前台传入,如果用 5D+rR<pD}"
Fe L !%z
webwork,甚至可以直接在配置文件中指定。 ?uh%WN6nU]
`}.jH1Fx/m
下面给出一个webwork调用示例: adY ,Nz
java代码: R+r;V ]-/
<H,E1kGw9
bUU\bc
/*Created on 2005-6-17*/ br;~}GR_h
package com.adt.action.user; }y>/#]X
yU|=)p5
import java.util.List; y3@m1>]09
O%s7 }bR3
import org.apache.commons.logging.Log; z?<Xx?Kk
import org.apache.commons.logging.LogFactory; a! gj_
import org.flyware.util.page.Page; >c)-o}bd^
^UmhSxQ##
import com.adt.bo.Result; q"0_Px9P
import com.adt.service.UserService;
#sm@|'Q%
import com.opensymphony.xwork.Action; |BEoF[1
o)WzZ,\F^J
/** HuLvMYF
* @author Joa AGhr(\j
*/ R!>l7p/|H)
publicclass ListUser implementsAction{ Y>2oU`ly,
^]k=*>{
R
privatestaticfinal Log logger = LogFactory.getLog
VXPsYR&
Ju-#F@38
(ListUser.class); D4jZh+_|S
n,#o6ali>
private UserService userService; 6GMwB@ b
s:xt4<
private Page page; ^XT;n
woUt*G@
privateList users; |U`ASo
ST1;i5
/* /lLG|aAe
* (non-Javadoc) &SMM<^P.
* $Zn>W@\
* @see com.opensymphony.xwork.Action#execute() \*mKctpz]6
*/ jO.c>C[?
publicString execute()throwsException{ %Y=
Result result = userService.listUser(page); Hy1pIUsx
page = result.getPage(); J3 xi5S
users = result.getContent(); ra
F+Bt`
return SUCCESS; a\m0X@Q
} ,a3M*}Y~3
)O ,+'w?
/** \SooIEl@
* @return Returns the page. PG{"GiZz=
*/ Zt \3y
public Page getPage(){ >p29|TFbV
return page; ]#;u]
} TBmmC}PEd
F%I*m^7d
/** Ask~
* @return Returns the users. >P}6/L
*/ |@rYh-5
publicList getUsers(){ PmA_cP7~
return users; g$U7bCHG
} N&G;`
'XI-x[w
/** #]2,1dJ
* @param page RY}:&vWDk
* The page to set. .*Axr\x3
*/ mW)C=X%
publicvoid setPage(Page page){ |!cM_&
this.page = page; Na.)!h_Kn'
} uA%cie
& &:ZY4`
/** i9^m;Y)^I
* @param users a/Cc.s
* The users to set. 7
V=%&+
*/ ,#.9^J
publicvoid setUsers(List users){ 6C- !^8[f
this.users = users; TUi<
} /mQ9}E4X
,-)ww:
/** 'ALe>\WO
* @param userService r5Xi2!
* The userService to set. i}kMo@
*/ %(~8a
publicvoid setUserService(UserService userService){ b/UjKNf@
this.userService = userService; U=N]XwjVK<
} sDS0cc6e
} L{u1_
$+n5l@W
p><DA fB
`l-R?C?*!
"uU[I,h
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, GE#LcCa
?>iZ){0,
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 *oru;=D@8
T2}ccnDi
么只需要: -hKtd3WbT
java代码: nE"0?VNW$
M7gM#bv>L
trg&^{D<
<?xml version="1.0"?> CW@G(R
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +zzS
8_uh2`+Bvb
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [KsVI.gn
0hX@ta[Up
1.0.dtd"> ]*\<k
oT^r
<xwork> KDYyLkI dr
C72btS
<package name="user" extends="webwork- C/!8NV1:4
(^= Hq'D
interceptors"> (Ek=0;Cr
@v=A)L
<!-- The default interceptor stack name )}SiM{g
&;@U54,wV
--> \\,z[C
<default-interceptor-ref n4G53+y'
jIL$hqo
name="myDefaultWebStack"/> uH8`ipX
.iH#8Z
<action name="listUser" YbE1yOJ&m
;/ao3Q
class="com.adt.action.user.ListUser"> 1a;&&!X
<param UE/N-K)`
%M;{+90p>t
name="page.everyPage">10</param> >Av%[G5=h#
<result p&(~c/0
^g*/p[
name="success">/user/user_list.jsp</result> KDy:A>_ G"
</action> 'W|@d8}h
ZUUfn~ORc
</package> Y\ G^W8
&Qq4xn+J
</xwork> dIDs~
!FR1yO'd>
Yq%D/dU8
P7p'j
oxL4* bqZ
e3 {L%rQE
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 0Z>oiBr4
(r )fx
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 d^jIsE `
cRC)99HP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Ow7I`#P
IXmO1*o@
POvpaPAZ<
!YEU<9
[8C6%n{W
我写的一个用于分页的类,用了泛型了,hoho g@7j<UY
k0R;1lZ0n
java代码: 1">]w2je:
=v]eQIp
"6%vVi6
package com.intokr.util; 9@|X~z5E
Y/w) VV
import java.util.List; 9 ulr6
P1mPC
/** r.;(Kx/M
* 用于分页的类<br> =rDIU&0Y
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 7w=%aW|
* wuTCdBu6hU
* @version 0.01 CQNt
* @author cheng /A) v$Bv=
*/ A4W61f
public class Paginator<E> { eX>X=Ku
privateint count = 0; // 总记录数 _[W`!#"
privateint p = 1; // 页编号 Wy%F
privateint num = 20; // 每页的记录数 <U$A_]*w
privateList<E> results = null; // 结果 ,/g\;#:{@]
nNff~u)I
/** K*Tvo`
* 结果总数 (FAd'$lhX}
*/ {1
94u%'
publicint getCount(){ /Iu._2
return count; jq&$YmWp
} =}~hbPJM
hOx">yki
publicvoid setCount(int count){ 3f:I<S7
this.count = count;
<&'r_m
} YA>du=6y\
`$\Y,9E}x
/** <`q|6XWL
* 本结果所在的页码,从1开始 _k@{>
?(a
* Q( KLx )
* @return Returns the pageNo. Wwf#PcC]
*/ 5i$~1ZC
publicint getP(){ 41TB
return p; 9c=_p'G3Fw
} K/u`Wz~A
SS;QPWRZ
/** ?WX&,ew~
* if(p<=0) p=1 Zh.fv-Ecp
* n]@+<TA<uA
* @param p <nj[=C4v
*/ )gCHwu
publicvoid setP(int p){ k852M^JP
if(p <= 0) soZw""|v
p = 1;
Xze
this.p = p; s%z'1KPS
} _rqOzE)
)8yee~+TN
/** OR^Wd
* 每页记录数量 -j[n^y'v
*/ 5@Q4[+5&_
publicint getNum(){ MOG[cp
return num; kI3-G~2
} +2w54X%?M
WJU`
g
/** j#U?'g
* if(num<1) num=1 Y(SgfWeK@1
*/ c+G: bb%p
publicvoid setNum(int num){ 685o1c|
if(num < 1) 38Z"9
num = 1; XI\aZ\v
this.num = num; Rhx7eU#&
} BQBO]<99
h ;5
-X7
/** bYdC.AE
* 获得总页数 "ngYh]Git$
*/ KW&&AuPb}
publicint getPageNum(){ r[Q$w>
return(count - 1) / num + 1; n a2"Sy=Yi
} &bj :,$@
5!Z+2Cu]
/** _:'m/K3Ee
* 获得本页的开始编号,为 (p-1)*num+1 p^YE"2 -
*/ FzpWT-jnDd
publicint getStart(){ 0mj=\ j
return(p - 1) * num + 1; GKY:"q&h
} nHKEtKDd
0m`7|80#P
/** 9rao&\eH
* @return Returns the results. _|TE )h
*/ n/?5[O-D]
publicList<E> getResults(){ 5.[{PJ]bq
return results; 2,&lGyV#
} cJ8F#t
&F'v_9
public void setResults(List<E> results){ =b% J@}m`&
this.results = results; d=qpTb;(
} yK?~XV:
TKLy38
public String toString(){ 31>k3IP&
StringBuilder buff = new StringBuilder 0uU%jN$
kM3BP&
3m1
(); MmWJYF=
buff.append("{"); &OhKx
buff.append("count:").append(count);
o@LjSQ5!
buff.append(",p:").append(p); qqzQKN
buff.append(",nump:").append(num); : 6>H\
buff.append(",results:").append HB`pK'gz
v[a#>!;s
(results); 2J4|7UwJ
buff.append("}"); DJQ]NY|
return buff.toString(); 1~ SY
} N@MeaO
GPR`=]n& &
} HqXo;`Yy}
E;4Ns
2hJ{+E.m