Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 41;)-(1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @P70W<<
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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 A
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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 <:cpz* G4
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分页支持类: ^('cbl
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java代码: (@?eLJlT
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package com.javaeye.common.util; (n=Aa;
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import java.util.List; 9 }n,@@
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publicclass PaginationSupport { 2
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publicfinalstaticint PAGESIZE = 30; &l!$Sw-u;
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privateint pageSize = PAGESIZE; 6<76O~hNZ
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privateList items; 9%TT>2#
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privateint totalCount; #O6
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privateint[] indexes = newint[0]; C
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privateint startIndex = 0; fv5C!> t
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public PaginationSupport(List items, int ZV#$Z
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totalCount){ `G0*l|m>
setPageSize(PAGESIZE); n'3u ]~7^
setTotalCount(totalCount); V(I7*_ZFl
setItems(items); @$ftG
setStartIndex(0); /yt7#!tm+
} a],h<wGEx
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public PaginationSupport(List items, int _jDS"
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totalCount, int startIndex){ %ph"PR/t?
setPageSize(PAGESIZE); 4zX=3iBt
setTotalCount(totalCount); Q%M_
setItems(items); Z*h ;e;
setStartIndex(startIndex); :R3P 58>
} uA^hCh-js
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public PaginationSupport(List items, int - XLo0
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totalCount, int pageSize, int startIndex){ /THNP 8.
setPageSize(pageSize); wVQdUtmk
setTotalCount(totalCount); _2; ^v`[
setItems(items); $Br>KJ%'g
setStartIndex(startIndex); -+ko}He
} }Qb';-+;d
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publicList getItems(){ 9IOGc}
return items; Wv NI=>
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publicvoid setItems(List items){ CX.SYr&!R
this.items = items; dWjx"7^
} /+N|X
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publicint getPageSize(){ ennR@pg
return pageSize; ?Oqzd$-
} |""=)-5N
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publicvoid setPageSize(int pageSize){ U~CdU
this.pageSize = pageSize; ki`8(u6l
} H)`@2~Y
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publicint getTotalCount(){ S$\.4*_H\
return totalCount; ;raz6DRO
} OZa88&
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publicvoid setTotalCount(int totalCount){ ">4PePt.n
if(totalCount > 0){ TZj[O1E
this.totalCount = totalCount; UDVf@[[hN
int count = totalCount / )7k&`?Mh
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pageSize; OWZS3Y+
if(totalCount % pageSize > 0) q;ZLaX\bFl
count++; RrKfTiK H
indexes = newint[count]; U>in2u9
for(int i = 0; i < count; i++){ k06xz#pL
indexes = pageSize * rNZO.qijz
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i; ^DzL$BX
} MSK'2+1T@g
}else{ yAAG2c4(
this.totalCount = 0; kq>GMUl~@
} di--:h/
} ,TEuM|
@W#fui<<}Y
publicint[] getIndexes(){ fEB195#@9
return indexes; b~jIv:9T
} epn#qeX
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publicvoid setIndexes(int[] indexes){ n}0za#G
this.indexes = indexes; is9}ePC7Xu
} r)OO&. P@j
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publicint getStartIndex(){ 6k:y$,w
return startIndex; IKGTsA;
} :4%<Rp
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publicvoid setStartIndex(int startIndex){ ujiZM
if(totalCount <= 0) &{ DR6
this.startIndex = 0; 1;aF5~&
elseif(startIndex >= totalCount) ;i.I&*t
this.startIndex = indexes l<W*/}3
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[indexes.length - 1]; .\Ul!&y
elseif(startIndex < 0) c6t2Q6zV
this.startIndex = 0; >6OCKl
else{ sTt9'P`
this.startIndex = indexes >_-!zjO8u
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[startIndex / pageSize]; NvUu.
} ud yAP>
} :
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publicint getNextIndex(){ 09G9nu ;&{
int nextIndex = getStartIndex() + SOhSg]g
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pageSize; V_Xy2<V
if(nextIndex >= totalCount) w~4
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return getStartIndex(); =x=1uXQv5
else nrF%wH/5
return nextIndex; ;&If9O1
} O;UiYrXU
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publicint getPreviousIndex(){ @55bE\E?@
int previousIndex = getStartIndex() - ^I@ey*$
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pageSize; anK[P'Y
if(previousIndex < 0) ~l(G6/R
return0; C5>{Q:.`e'
else #!w:_T%
return previousIndex; U&,r4>V@h>
} 6
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} wDB)&b
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抽象业务类 4\&H?:c.
java代码: ?UxG/]",
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/** ^Yf3"D?&
* Created on 2005-7-12 \k|_&hG
*/ xR0~S
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package com.javaeye.common.business; }/_('q@s\
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import java.io.Serializable; nsZDZ/jx
import java.util.List; 8dr0 DF$c
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import org.hibernate.Criteria; qRgK_/[]
import org.hibernate.HibernateException;
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import org.hibernate.Session; p^p'/$<6_
import org.hibernate.criterion.DetachedCriteria; 2dv|6p
import org.hibernate.criterion.Projections; U#8\#jo
import D9}d]9]$
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org.springframework.orm.hibernate3.HibernateCallback; eA~J4k_
import K{,
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org.springframework.orm.hibernate3.support.HibernateDaoS JOA%Y;`<#
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upport; H%*~l
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import com.javaeye.common.util.PaginationSupport; j'G"ZPw1
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public abstract class AbstractManager extends (jp1; #P!
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HibernateDaoSupport { {;]uL`abi?
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privateboolean cacheQueries = false; *raIV]W3
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privateString queryCacheRegion; =@bXGMsV!
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publicvoid setCacheQueries(boolean Q.j-C}a
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cacheQueries){ 1h#w"4
this.cacheQueries = cacheQueries; I'KR'1z 9
} R=2
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publicvoid setQueryCacheRegion(String o%kSR ]V|
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queryCacheRegion){ ~J8cS
this.queryCacheRegion = $=\oJ-(!@S
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queryCacheRegion; ~0VwF
} I>N-95
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publicvoid save(finalObject entity){ ==jkp
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getHibernateTemplate().save(entity); h1Ke$#$6
} B|$\/xO
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publicvoid persist(finalObject entity){ !1ie:z>s
getHibernateTemplate().save(entity); d+gk q\
} yrxx+z|wR
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publicvoid update(finalObject entity){ oN1!>S9m
getHibernateTemplate().update(entity); <[ g$N4
} x]yHBc
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publicvoid delete(finalObject entity){ w\0Oz?N
getHibernateTemplate().delete(entity); [15hci+-
} &* V0(
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publicObject load(finalClass entity, rwi2kk#@P
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finalSerializable id){ LM'*OtpDG
return getHibernateTemplate().load &(z8GYBr
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(entity, id); (P]^8qc
} Ymrpf
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publicObject get(finalClass entity, j`LT`p"9S
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finalSerializable id){ ;
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return getHibernateTemplate().get
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(entity, id); IdQwLt
} S7\|/h:4
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publicList findAll(finalClass entity){ OTy4"%
return getHibernateTemplate().find("from H|(*$!~e
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" + entity.getName()); kBDe*K.V
} q) zu}m
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publicList findByNamedQuery(finalString j*3sjOoC
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namedQuery){ J^<j=a|D
return getHibernateTemplate x.yb4i=Jq
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().findByNamedQuery(namedQuery); K{[Fa,]'
} ^/5E773
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publicList findByNamedQuery(finalString query, QdG?"Bdt2
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finalObject parameter){ 9N3oVHc?
return getHibernateTemplate K\%"RgF@&
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().findByNamedQuery(query, parameter); \gPNHL*
} ~9{-I{=
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publicList findByNamedQuery(finalString query, sO f)/19
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finalObject[] parameters){ J4R
return getHibernateTemplate 5SPl#*W
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().findByNamedQuery(query, parameters); }M"'K2_Z
} ^_#gIT\
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publicList find(finalString query){ YJtOdgG|q
return getHibernateTemplate().find jWb\"0)
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(query); y^Xxa'y
} Se]t;7j
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publicList find(finalString query, finalObject iz|9a|k6x
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parameter){ *^$N$t/2
return getHibernateTemplate().find e715)_HD
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(query, parameter); R/KWl^oNj
} TY{?4
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public PaginationSupport findPageByCriteria <a/ZOuBzZ
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(final DetachedCriteria detachedCriteria){ u+i/CE#w
return findPageByCriteria \=:g$_l
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Jv$2wH
} 0i1?S6]d-
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public PaginationSupport findPageByCriteria @X / =.
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(final DetachedCriteria detachedCriteria, finalint S>zKD
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startIndex){ U";Rp&\3;
return findPageByCriteria %4g4 C#
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(detachedCriteria, PaginationSupport.PAGESIZE, 9bYHb'70
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startIndex); P_}_D{G
} l~>rpG
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public PaginationSupport findPageByCriteria W2V@\
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(final DetachedCriteria detachedCriteria, finalint ZXRN?b
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pageSize, TuPxyB
finalint startIndex){ J!qEj{
return(PaginationSupport) ku8Z;ONeH
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getHibernateTemplate().execute(new HibernateCallback(){ _J#Hq 'K
publicObject doInHibernate m=b+V#4i(
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(Session session)throws HibernateException { _34YH 5
Criteria criteria = #nL0Hx7]E
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detachedCriteria.getExecutableCriteria(session); 2QD
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int totalCount = T</gWW
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((Integer) criteria.setProjection(Projections.rowCount MjosA R
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()).uniqueResult()).intValue(); -&^( T
criteria.setProjection {nWtNyJpS
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(null); &l)v'
List items = 0iq$bT|
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criteria.setFirstResult(startIndex).setMaxResults 57%cN-v*
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(pageSize).list(); X=}0+W
PaginationSupport ps = @)Y7GM+^
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new PaginationSupport(items, totalCount, pageSize, h*'5h!
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startIndex); .Zm }
return ps; aYX '&k
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} ?-p aM5Q+
}, true); u+I3VK_)
} c_=zd6 b$S
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public List findAllByCriteria(final Ft>8 YYyU
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DetachedCriteria detachedCriteria){ ;qQzF
return(List) getHibernateTemplate D-EM
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().execute(new HibernateCallback(){ eesLTyD2_
publicObject doInHibernate yr DYw T
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(Session session)throws HibernateException { J@-9{<
Criteria criteria = @Kb~!y@G
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detachedCriteria.getExecutableCriteria(session); rkXSygb
return criteria.list(); 3hjwwLKG$
} _)\,6| #
}, true); WWzns[$f
} oMf h|B
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public int getCountByCriteria(final 1a4 $.
{
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DetachedCriteria detachedCriteria){ q&x#S_!
Integer count = (Integer) k}7)pJNj
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getHibernateTemplate().execute(new HibernateCallback(){ Hc3/`.nt
publicObject doInHibernate @K>Pw arl
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(Session session)throws HibernateException { G*V
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Criteria criteria = NsK >UJ'
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detachedCriteria.getExecutableCriteria(session); x=+H@YO\
return !9Ni[8&Fg0
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criteria.setProjection(Projections.rowCount <FLc0s
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()).uniqueResult(); gW%(_H mX
} a2n#T,kq&
}, true); 6n g9 o6
return count.intValue(); ,\"gN5[$(
} /d;l:
} =-Tetp
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用户在web层构造查询条件detachedCriteria,和可选的 SJe;T
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 kv2:rmv
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PaginationSupport的实例ps。 n`1i k'x?
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ps.getItems()得到已分页好的结果集 *?\Nioii
ps.getIndexes()得到分页索引的数组 Dbd5d]]n3
ps.getTotalCount()得到总结果数 s6IuM )x
ps.getStartIndex()当前分页索引 n_Dhq (.
ps.getNextIndex()下一页索引 |M&/(0
ps.getPreviousIndex()上一页索引 A5\S0l$Q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =nl,5^
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 YXEZ&$e'
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一下代码重构了。 0v?,:]A0E
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我把原本我的做法也提供出来供大家讨论吧: kp|reKM/
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首先,为了实现分页查询,我封装了一个Page类: Z:{Z&HQC
java代码: bB["Qd}Q
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/*Created on 2005-4-14*/ Nx"?'-3Hm
package org.flyware.util.page; RPu-E9g@
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/** YH9BJ
* @author Joa KK}&4^q
* B5hGzplS
*/ -JK+{<
publicclass Page { rm7UFMCR6i
ORO~(%-(e
/** imply if the page has previous page */ 4{_5z7ody
privateboolean hasPrePage; Wil+"[Ge
>8##~ZuF+
/** imply if the page has next page */ v3B
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privateboolean hasNextPage; ~H.;pJ{ 8
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/** the number of every page */ 8I'?9rt2M
privateint everyPage; bYz:gbs]4|
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/** the total page number */ &fcRVku
privateint totalPage; Nb6HM~
W*0KAC`m
/** the number of current page */ Z=xrjE
privateint currentPage; |[ge,MO:
c=5$bo]LI
/** the begin index of the records by the current C,E 5/XW
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query */ n1ICW 9
privateint beginIndex; @'QB rE
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/** The default constructor */ bFpwq#PDW>
public Page(){ rr*IIG&.5
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} \,WPFV
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/** construct the page by everyPage mxIEg?r(
* @param everyPage m{g{"=}YR
* */ yC
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public Page(int everyPage){ C-Mop,w
this.everyPage = everyPage; xc!"?&\*
} \<5xf<{
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/** The whole constructor */ B`vV[w?
public Page(boolean hasPrePage, boolean hasNextPage, tNjrd}8s
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int everyPage, int totalPage, p(Sfw>t(
int currentPage, int beginIndex){ lr1i DwZV
this.hasPrePage = hasPrePage; [W2k#-%G
this.hasNextPage = hasNextPage; UwLa9Dn^
this.everyPage = everyPage; ;3w W)gL1
this.totalPage = totalPage; yk=H@`~!
this.currentPage = currentPage; oyUf/Sl
this.beginIndex = beginIndex; 6|zA,-=
} 0P|WoCX
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/** :G!Kaa,r
* @return lHx$F?
* Returns the beginIndex. ]'"$qm:
*/ }&=C*5JN
publicint getBeginIndex(){ fE(rDQI
return beginIndex; ,QK>e;:Be
} q|~9%Pujg
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/** $+tkBM
* @param beginIndex rIXAn4,dTv
* The beginIndex to set. @=$;^}JS|
*/ VL\6U05Z
publicvoid setBeginIndex(int beginIndex){ |2mEowAd
this.beginIndex = beginIndex; BM3nZ<%3
} 9N9;EY-U
=KX:&GU
/** NK#f Gz*,(
* @return k?_Miqr
* Returns the currentPage. hE>Mo$Q(
*/ |[*b[O
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publicint getCurrentPage(){ B$fL);l-
return currentPage; 1e}wDMU(
} V< J~:b1V
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/** }%%| '8
* @param currentPage pBHr{/\5
* The currentPage to set. u|+O%s TQ
*/ uoF9&j5E@Z
publicvoid setCurrentPage(int currentPage){ . uhP(
this.currentPage = currentPage; n#4Ra+dD
} +~7@K{6q-
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u<
/** *dGW=aM#C
* @return ,9=a(j"
* Returns the everyPage. !fZxK CsQ
*/ v,kedKcxv'
publicint getEveryPage(){ !.9NJ2'8
return everyPage; L='GsjF0}
} KX{ S8_
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/** w*
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* @param everyPage m#Rll[
* The everyPage to set. O4 [[9
*/ *vht</?J
publicvoid setEveryPage(int everyPage){ @;pTQ
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this.everyPage = everyPage; =YI<L8@g~
} _Nw-|N .
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/** 0nBAO
* @return zg[ksny
* Returns the hasNextPage. d]CRvzW
*/ pVLfZ?78
publicboolean getHasNextPage(){ )wmXicURC
return hasNextPage; XmLHZ,/
} )abo5
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/** ]@Q14
* @param hasNextPage kZfO`BVL
* The hasNextPage to set. <wa}A!fu
*/ iB{O"l@w
publicvoid setHasNextPage(boolean hasNextPage){ i,,U D
this.hasNextPage = hasNextPage; nXXyX[c4e
} Y*J,9
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/** st~f}w@
* @return 7R ;!
* Returns the hasPrePage. Wo\NX05-?
*/ (C1]R41'
publicboolean getHasPrePage(){ D[ny%9 :
return hasPrePage; " J$vt`
} wtaeF+u-R-
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/** iN<Tn8-YH6
* @param hasPrePage a>6!?:Rj
* The hasPrePage to set. S&FMFXF@
*/ ` O-$qT,_
publicvoid setHasPrePage(boolean hasPrePage){ @32JMS<
this.hasPrePage = hasPrePage; yPKeatH]
} g?)9zJ9
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/** YEQ}<\B\&
* @return Returns the totalPage. [
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* .(`#q@73
*/ [T.kwQf4$
publicint getTotalPage(){ D>PB|rS@
return totalPage; xrS;06$
} \f05(ld
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/** /(5SJ(a
* @param totalPage ^dld\t:tV7
* The totalPage to set. BNnGtVAbZ
*/ S!0<aFh
publicvoid setTotalPage(int totalPage){ X*/jna"*
this.totalPage = totalPage; ZU5hHah.t
} 7jvf:#\LtL
}]'Z~5T
} ['Hl$2 j
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 `a*[@a#
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个PageUtil,负责对Page对象进行构造: S)T~vK(n
java代码: iG!tRNQ{y
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/*Created on 2005-4-14*/ %@Bl,!BJ,
package org.flyware.util.page; X3P~z8_
1.6yi];6
import org.apache.commons.logging.Log; WnyEdYA
import org.apache.commons.logging.LogFactory; [2"a~o\
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/** }.>( [\q
* @author Joa @2na r<
* g ]e^;
*/ c_"]AhV~Mg
publicclass PageUtil { 9LI#&\lba
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privatestaticfinal Log logger = LogFactory.getLog ?Id3#+-O
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(PageUtil.class); @G@,)`p4?
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/** J^m#984
* Use the origin page to create a new page E_[|ZrIO&*
* @param page N =FX3Z
* @param totalRecords <b.?G
* @return JK))Cuh
*/ 1qp<Fz[
publicstatic Page createPage(Page page, int 1t w>C\
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totalRecords){ ^K.
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return createPage(page.getEveryPage(), P/6$T2k_
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page.getCurrentPage(), totalRecords); I]+xerVd
} 1zqIB")s>
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/** E!nEB(FD
* the basic page utils not including exception va 7I_J
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handler C,r[H5G#
* @param everyPage a|?&
* @param currentPage Jh`Pq,B:
* @param totalRecords dCc"Qr[k
* @return page T5H[~b|9-
*/ T;!: A
publicstatic Page createPage(int everyPage, int }-4@EC>
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currentPage, int totalRecords){ N1/)Fk-z
everyPage = getEveryPage(everyPage); ldk (zAB.
currentPage = getCurrentPage(currentPage); R!{^qHb
int beginIndex = getBeginIndex(everyPage, jeLRS8];
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currentPage); v8
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int totalPage = getTotalPage(everyPage, Kcf1$`F24
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totalRecords); *9Ta0e*
boolean hasNextPage = hasNextPage(currentPage, `s1>7XWf
@pq2Z^SQ H
totalPage); $1lI6 =
,
boolean hasPrePage = hasPrePage(currentPage); mWEaUi)Zz
l ld,&N8
returnnew Page(hasPrePage, hasNextPage, +5~5BZP
everyPage, totalPage, J,q6
currentPage, Uao8#<CkvJ
0i/!by{@
beginIndex); jEU`ko_
} Xf
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|
privatestaticint getEveryPage(int everyPage){ B\^myg4
return everyPage == 0 ? 10 : everyPage; )c*NS7D~f
} 0APh=Alq
8k[=$Ro
privatestaticint getCurrentPage(int currentPage){ p6S{OUiG
return currentPage == 0 ? 1 : currentPage; |y%pJdPk=
} W3Gg<!*Uo
zy8Z68%E`*
privatestaticint getBeginIndex(int everyPage, int Dnk}
E3hql3=
currentPage){ *ay&&S*
return(currentPage - 1) * everyPage; &k53*Wo
} Bk)E]Fk|
}SD*@w
privatestaticint getTotalPage(int everyPage, int }Br=eaY
-nK\+bTL}
totalRecords){ lQ&"p+n
int totalPage = 0; G42J
B8Vhl:p
if(totalRecords % everyPage == 0) )WWqi,T}
totalPage = totalRecords / everyPage; k65V5lb
else _"0,
totalPage = totalRecords / everyPage + 1 ; 7 +]+S`p
~t=73fwB
return totalPage; t .\<Q#bN#
} Cj/J&PDQ
^lvYj
E
privatestaticboolean hasPrePage(int currentPage){ bqPaXH
n
return currentPage == 1 ? false : true; srL|Y&8 p
} <[l0zE5Z8'
!m {d6C[
privatestaticboolean hasNextPage(int currentPage, 1Jm'9iy3
E^s<5BC;
int totalPage){ o,NTIh
return currentPage == totalPage || totalPage == , B90r7K:
s8:-*VR9
0 ? false : true; 9Gh:s6
} +4
W6{`
+jD*Jtb<
)70i/%}7
} ]#NJ[IZb
simD<&p
,vcg%~-
&0`[R*S
JX)%iJq#
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。 wjzR 8g0bQ
Qr.SPNUFK
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 r+RFDg/
KT3n-Y-,
做法如下: QH5[}zs8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y|b&Rup
w|,BTM:e
的信息,和一个结果集List: cM?i _m
java代码: F=g+R~F
n9H4~[JiC
[z[<onFIq
/*Created on 2005-6-13*/ /LK,:6
package com.adt.bo; 2%Mgg,/~
$-w&<U$E
import java.util.List; "7z1V{ ;Y
/_(q7:<ZF
import org.flyware.util.page.Page; :aHLr[%Mz
TC* 78;r
/** mVsghDESJ)
* @author Joa ` W}Bc
*/ OF1fS\P<>
publicclass Result { af-
1F,>siuh ,
private Page page; FW@(MIH
zn)Kl%N^
private List content; "?HDv WP=w
"3;b,<0
/** aj`_*T"A
* The default constructor z)_h"y?H{%
*/ /^pPT6
public Result(){ A.5`+
super(); i-FsA
} b#[EkI 0@
SJ8CBxA
/** B:]%Iu|
* The constructor using fields PZ.q
* WKvG|YRDq
* @param page zL@FN sYVM
* @param content "i^<
H
*/ `^mY*Cb e
public Result(Page page, List content){ BM>'w,$KL
this.page = page; dWi:V7t+
this.content = content; $6DA<v^=z
} oYmLJzCf
7#[8td
/** *l.tsICmbP
* @return Returns the content. @,Kl"i;
*/ |*5HNP
publicList getContent(){ efrVF5,y?
return content; x T8pwTO
} (x!Tb2mlk
;r3Xh)k;
/** <$@*'i^7Ez
* @return Returns the page. U][\|8i
*/ 7^FJ+gN8b
public Page getPage(){ !v\_<8
return page; ),rd7GB>
} RQO&F$R=
:~wU/dEEiz
/** P*:9u>
* @param content `G_k~ %
* The content to set. ;_6CV
*/ u`
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public void setContent(List content){ _j sJS<21
this.content = content; 6F:<c
} [k{2)g
Ftw;T|
/**
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* @param page c]PG5f xf
* The page to set. TfnBPO
*/ I6vy:5d
publicvoid setPage(Page page){ U'p-Ko#
this.page = page; $mu*iW\{
} L_O*?aaZ
} tDQuimYu7
]9PQKC2&
Me2qOc^Z-
sL!+&Id|
; S~
2. 编写业务逻辑接口,并实现它(UserManager, oY<R[NYKu
'`sZo1x%f
UserManagerImpl) <HB@j}qi
java代码: k1E(SXcW9
kK~,?l
;hb_jW-0W
/*Created on 2005-7-15*/ PHR:BiMZ
package com.adt.service; z)F<{]%
RAU"
import net.sf.hibernate.HibernateException; 0WI@BSHnM
eufGU)M
import org.flyware.util.page.Page; g:eqB&&
^\Epz*cL
import com.adt.bo.Result; e1/{bX5
AU4K$hC^
/** GV0-"9uwX~
* @author Joa DIBoIWSuR
*/ AlA:MO]NM
publicinterface UserManager { f)19sjAJk
d6f+[<<
public Result listUser(Page page)throws lPZYd8
m <'&`B;
HibernateException; <`?V:};Q
qAW?\*n5N
} TD-o-*mO
EECuJ+T
2(i|n=
?k$'po*Eq
sd&^lpH
java代码:
$5\+QW
ac!!1lwA
9Q>85IiT
/*Created on 2005-7-15*/ F3e1&aK6{
package com.adt.service.impl; @@V{W)rl
qO{Yr$V%
import java.util.List; `6xr:s
<7
xX/Z}M
import net.sf.hibernate.HibernateException; "[dfb#0z`
O9ar|8y
import org.flyware.util.page.Page; ^m['VK#?
import org.flyware.util.page.PageUtil; ''Hx&
B'&QLO|
import com.adt.bo.Result; W2BZG(dm
import com.adt.dao.UserDAO; H>]A|-rG#
import com.adt.exception.ObjectNotFoundException; b?K`DUju{0
import com.adt.service.UserManager; Ctx`b[&KXX
t.Yf8Gy
/** P09f
* @author Joa RXRoMg!-P
*/ ;6M [d
publicclass UserManagerImpl implements UserManager { B}+li1k
F R(k==pZ
private UserDAO userDAO; LYO2L1u)
v>/_U
/** B!1h"K5.($
* @param userDAO The userDAO to set. {s>V'+H(F
*/ +~$pkxD"
publicvoid setUserDAO(UserDAO userDAO){ G^Va$ike
this.userDAO = userDAO; Mp?L9
} GK=b
8Dkq+H93
/* (non-Javadoc) ,lcSJ^yr
* @see com.adt.service.UserManager#listUser Y?ZzFd,i&
NXX/JJ+w
(org.flyware.util.page.Page) l5/gM[0_7
*/ B \LmE+a>
public Result listUser(Page page)throws SW}?y%~
mXs.@u/
HibernateException, ObjectNotFoundException { IU;a$
int totalRecords = userDAO.getUserCount(); \V#fl
if(totalRecords == 0) G|YNShK4=9
throw new ObjectNotFoundException |:]}u|O
m5v IS
("userNotExist"); ;;|.qgxc~
page = PageUtil.createPage(page, totalRecords); R PdFLC/
List users = userDAO.getUserByPage(page); :%>)S
returnnew Result(page, users); )4TP{tp
} E[cH/Rm
Bo$dIn2_
} rK\9#[?x
F+ %l=
fs
ERy=lP~gV
x~Dj2F ]
]\y]8v5(
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (H8JV1J
i1ScXKO
询,接下来编写UserDAO的代码: [1nUq!uTm
3. UserDAO 和 UserDAOImpl: Mc&Fj1h5
java代码: J7Mbv2D
IN75zn*%
Tje(hnN
/*Created on 2005-7-15*/ -3u ;U,}
package com.adt.dao; <eZ*LK?
[HI$[:[
import java.util.List; U!(es0rX
)-X/"d
import org.flyware.util.page.Page; ]h,iyWSs
wXtp(YwlH
import net.sf.hibernate.HibernateException; !;;7:!)P
< 0YoZSNGj
/** f]_'icP
* @author Joa 0xY</S
*/ p zZ+!d
publicinterface UserDAO extends BaseDAO { =*R6O,
_+.JTk
publicList getUserByName(String name)throws q~^!Ck+#*
[{`2FR:Cd
HibernateException; VeSQq
mVFo2^%v
publicint getUserCount()throws HibernateException; BOWBD@y
<_c8F!K)T
publicList getUserByPage(Page page)throws bObsj]
Nz}PcWF/
HibernateException; d^f rKPB
%lD+57=
} \!xCmQ
Y::O*I2
je5[.VT M
C57m{RH
q}!h(-y}5n
java代码: 80ox$U
A'.=SA2.Y
H~^)^6)^T
/*Created on 2005-7-15*/ '4SDAa2f
package com.adt.dao.impl; e^'|<0J
i\O^s ]
import java.util.List; )*`h)`\y
":f]egq
-
import org.flyware.util.page.Page; S+#|j
|#sOa
import net.sf.hibernate.HibernateException; 0?}n( f!S
import net.sf.hibernate.Query; &36SX<vZ
R1*4
import com.adt.dao.UserDAO; B%tWi
i4]oE&G
/** ]x{.qTtw
* @author Joa r?IBmatK/
*/ 0zE@?.
public class UserDAOImpl extends BaseDAOHibernateImpl k(M:#oA!
[Ky3WppR
implements UserDAO { x
FWhr#5,
>lfuo
/* (non-Javadoc) ,ryL("G
* @see com.adt.dao.UserDAO#getUserByName R1D ;
u`&lTJgF/O
(java.lang.String) #y[U2s Se
*/ YM};85 K
publicList getUserByName(String name)throws PfZS"yk
!?v_.
HibernateException { !LzA
String querySentence = "FROM user in class !sSq 4K
Mc<u?H
com.adt.po.User WHERE user.name=:name"; @Ns[qn;9
Query query = getSession().createQuery kY @(-
z DU=2c4W9
(querySentence); loO"[8i.k
query.setParameter("name", name); X6",Xr!{
return query.list(); 1`YU9?
} Z %Ozzp/
DzQ
/* (non-Javadoc) </WeB3#6
* @see com.adt.dao.UserDAO#getUserCount() xDGS`o_w_
*/ Fs].Fa
publicint getUserCount()throws HibernateException { 6pSi-FH
int count = 0; N0.|Mb"?t
String querySentence = "SELECT count(*) FROM 4l+!Z, b
R(`:~@3\6
user in class com.adt.po.User"; !?(7g2NP)
Query query = getSession().createQuery tAF?.\x"g
7@
)
(querySentence); OQ7 `n<I<)
count = ((Integer)query.iterate().next m3TR}=n
-^5467
()).intValue(); K)BQ0v.:[
return count; 0/b
_T
} h%krA<G9
#{vC =m73
/* (non-Javadoc) t*=[RS*
* @see com.adt.dao.UserDAO#getUserByPage r!+{In+Z
W*t]
d
(org.flyware.util.page.Page) BMy3tyO
*/ @phVfP"M
publicList getUserByPage(Page page)throws fEX=csZ86
5&V=$]t
HibernateException { nuXL{tg6
String querySentence = "FROM user in class sVK?sBs]
+a3E=GJ
com.adt.po.User"; >
[J.
Query query = getSession().createQuery 8 {V9)U
w y|^=#k
(querySentence); V`1,s~"q
query.setFirstResult(page.getBeginIndex()) -}9^$}PR
.setMaxResults(page.getEveryPage()); N,c!1:b
return query.list(); D2?H"PH
} )63
$,y-;$
dPwyiV0
} Z*ip=FYR
P"8Ix
\3$!) z
u3C_Xz
RqtBz3v
至此,一个完整的分页程序完成。前台的只需要调用 ,^1zG
WJ25fTsG
userManager.listUser(page)即可得到一个Page对象和结果集对象 0RT 8N=B83
du66a+@t
的综合体,而传入的参数page对象则可以由前台传入,如果用 x}yl Rg`[
:<t=??4m
webwork,甚至可以直接在配置文件中指定。 MLu!8dgI
W<r<K=`5P
下面给出一个webwork调用示例: ];OvV ,*
java代码: d )O^(y1r
e@Lxduq
=~GP;=6
/*Created on 2005-6-17*/ (Jk&U8y
package com.adt.action.user; AJ bCC
c3^!S0U
import java.util.List; _^r};}-}
9%"7~YCDas
import org.apache.commons.logging.Log; ^_;'9YD
import org.apache.commons.logging.LogFactory; WVdV:vJ-
import org.flyware.util.page.Page; .|Huzk+
UqOBr2UmG
import com.adt.bo.Result; ;!MQ@Fi^
import com.adt.service.UserService; rm8Ys61\=
import com.opensymphony.xwork.Action; +;?mg(:
@-'a{hBR
/** q 84*5-
* @author Joa FH+X<
*/ 5To@d|{
publicclass ListUser implementsAction{ Y~WdN<g
%_ibe
privatestaticfinal Log logger = LogFactory.getLog jYHn J}<
*nCA6i
(ListUser.class); s-$Wc)l
dFm_"135
private UserService userService; %
i4
5
2.D2
o
private Page page; ABN4kM>%
tk&AZb,sP
privateList users; ;xZ+1zmL0
_MBhwNBxZ
/* hOY@vm&
* (non-Javadoc) >}+{;d
* xB
*b7-a
* @see com.opensymphony.xwork.Action#execute() `tk oS
*/ fp)SZu_*
publicString execute()throwsException{ g2vm]j
Result result = userService.listUser(page); T/_u;My;
page = result.getPage(); wa"0`a:`;
users = result.getContent(); rwRZGd *p
return SUCCESS; ^dI;B27E*
} CS7b3p!I
CO
wcus
/** 'J,UKK\5
* @return Returns the page. 5/=$p:E>
*/ ';tlV
u
public Page getPage(){ n<.7tr0f\
return page; /)ZjI
W"|
} FDMQLx f
b^/u9
/** x?Abk
* @return Returns the users. y, l[v39
*/ n-Iz!;q
publicList getUsers(){ >Xn,jMUW
return users; D+]mKPB
} q+?&w'8
]9oj,k
/** -9b=-K.y
* @param page \p4*Q}t
* The page to set. X+4Uh
I
*/ 9@*pC@I)
publicvoid setPage(Page page){ h4hAzFQ.s
this.page = page; T3wTMbZ!VK
} :zHSy&i`
q" VmuQ
/** yKML{N1D
* @param users o?baiOkH
* The users to set. \.i7(J]
*/ :3D8rqi:
publicvoid setUsers(List users){ JHxcHh
this.users = users; :Awwt0
} Z",0 $Gxu
1=5"j]0hY
/** 5U2%X
pO
* @param userService iC#a+G*N_M
* The userService to set. 1)z'-dQ-5$
*/ f(Xin3#'
publicvoid setUserService(UserService userService){ iJ{axa &
this.userService = userService; ] &8em1
} 3r~8:F"g
} T"g_a|7Tj
[<@L`ki
V^s, 3C
$_<[kci%
.x=abA$!9
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, &lzY"Y*hA0
[G_ ;78
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 4e#g{,
G#7*O`
么只需要: $O |Xq7dp
java代码: #un'?]tZF
LQF;T7VKS)
02]HwsvZ
<?xml version="1.0"?> <aPZE6z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork aj?ZVa6
]9QXQH
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;6V~yB
Id?-Og2iV
1.0.dtd"> /Z2u0jNArP
)
gl{ x
<xwork> ug%7}&
t]B`>SL3W
<package name="user" extends="webwork- nAQ[
-NbW,
c44s@E
interceptors"> #66i!}
Ku'a,\7z
<!-- The default interceptor stack name =ls+vH40&
JrBPx/?(,;
--> Yup#aeXY/
<default-interceptor-ref tar/n o
R&!;(k0
name="myDefaultWebStack"/> Wps^wY
DcxT6[
<action name="listUser" "/R?XCBZsb
%qV:h#
class="com.adt.action.user.ListUser"> Ea4zC|;
<param ]+G
.S-a
1#Vd)vSP
name="page.everyPage">10</param> Yv1yRoDv
<result 2z;nPup,
pauO_'j_1p
name="success">/user/user_list.jsp</result> zeGWM,!
</action> 2 4od74\
Af\@J6viF7
</package> EuHQp7
);HhV,$n
</xwork> 2H;#L`Z*
Lq3<&$
y_:{p5u
tO&n$$
"y8W5R5kL4
TTO8tT3[6}
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 -[*y{K@dh
\6AM?}v
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。 rX^uHq8
N(i.E5&9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 C#[P<= v
vAP1PQX;
b|V<Kp
GN(,` y
+/_XSo
我写的一个用于分页的类,用了泛型了,hoho iklZ[G%A0
l>|scs;TI
java代码: w!`e!}
`j{q
eS Z':p
package com.intokr.util; zn/>t-Bc
?yG[VW
import java.util.List; `j3 OFC{7E
8yIBx%"4MH
/** W2`3PEa
* 用于分页的类<br> fNda&
* 可以用于传递查询的结果也可以用于传送查询的参数<br> C\{ KB@C\*
* O\!'Ds+gX
* @version 0.01 3K||(
* @author cheng 1Y"9<ry
*/ jjrE8[
public class Paginator<E> { N~b0 b;e
privateint count = 0; // 总记录数 {.U:Ce
privateint p = 1; // 页编号 <0Y<9+g!
privateint num = 20; // 每页的记录数 K:13t|
privateList<E> results = null; // 结果 ,5U[#6^
"kFNOyj3\
/** NVQ.;" 2w
* 结果总数 ;mI^J=V3
*/ ,+d8
publicint getCount(){ O,7S1
return count; le_aIbB"P
} 3;jxIo$,
83]m/Iz
publicvoid setCount(int count){ ]D~Ibv{Y
this.count = count; K/(QR_@?
} @[v,q_^8
e2fv%
/** X!{K`~DRX
* 本结果所在的页码,从1开始 |7KWa(V5I
* >tkz%;6
* @return Returns the pageNo. Sz|kXk6&9
*/ p5"pQeS
publicint getP(){ %Cj_z
return p; `'3&tAy
} =i}lh}(
8,F|*YA
/** Aua}.Fl,
* if(p<=0) p=1 UvU@3[fw
* CL`+\
.
* @param p T++q.oFc
*/ @#^Y#
rxb
publicvoid setP(int p){ "Uf1;;b
if(p <= 0) /V cbT >=
p = 1; Jza?DhSAZ
this.p = p; @+nCNXK
} ]H{*Z3S
O46v
/** 0s Jp,4Vv
* 每页记录数量 _KtV`bF
*/ V^!^wLLi
publicint getNum(){ [jCYj0Qf8
return num; ;K7kBp\d
} a;Pn.@NVq
a>-qHX-l
/** 0t(c84o5
* if(num<1) num=1 _Wk*h}x
*/ SXe1Q8;
publicvoid setNum(int num){ 30SQ&j[N]
if(num < 1) ~K5A$s2
num = 1; QrFKjmD<
this.num = num; Y^DGnx("m
} 3.P7GbN
Xf"<
>M
/** O8>&J-+2
* 获得总页数 raSga'uT;
*/ rtbV*@Z
publicint getPageNum(){ p(="73
return(count - 1) / num + 1; AEx VKy
} 0Ntvd7"`}
l1`r%9gr
/** ^7i7yM}6(
* 获得本页的开始编号,为 (p-1)*num+1 h{zb)'R
*/ =_j<x$,b-
publicint getStart(){ Al@. KTK
return(p - 1) * num + 1; 3*\Q]|SI!
} r|]YS6
WrRY3X
/** BHU$QX
* @return Returns the results. {jwLVKT$
*/ x)N QRd
publicList<E> getResults(){ VR1[-OE
return results; ?F!c"+C
} &w`DF,k|
Q {~$7J
public void setResults(List<E> results){ ZNDi;6e
this.results = results; m]}U!XT
} =vQ J2Rg
lIx./Nf
public String toString(){ K0B<9Wi|
StringBuilder buff = new StringBuilder 0y/31hp
bWlYQ
(); _!vy|,w@e
buff.append("{"); =-r); d
buff.append("count:").append(count); f52P1V]
buff.append(",p:").append(p); f9<"
buff.append(",nump:").append(num); \RPwSx
buff.append(",results:").append gs/o cu
T>b"Gj/
(results); &Ruq8n<
buff.append("}"); Ndb7>"W
return buff.toString(); qP&:9eL
} %\|{_]h}y
QY<5o;m`
} '+vmC*-I(
r_,;[+!
`jr?I {m;