Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 vZ.<OD4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W g6H~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 ~dp f1fP
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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 hh*('n>[
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分页支持类: jY]51B
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java代码: }f?[m&<
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package com.javaeye.common.util; 5\#I4\
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import java.util.List; +jF2{"
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publicclass PaginationSupport { m|c[C\)By
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publicfinalstaticint PAGESIZE = 30; Y_!+Y<x7v
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privateint pageSize = PAGESIZE; *vuI'EbM
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privateList items; ,qv\Y]
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privateint totalCount; liH#=C8l*%
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privateint[] indexes = newint[0]; AD?XJ3
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privateint startIndex = 0; yV\%K6d|3&
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public PaginationSupport(List items, int HdB>CVuh
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totalCount){ -9,~b9$
setPageSize(PAGESIZE); UF#!6"C@
setTotalCount(totalCount); XC^*z[#4{
setItems(items); P@vUQ
setStartIndex(0); #O\as~-
} |.0~'
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public PaginationSupport(List items, int ;..z)OP_
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totalCount, int startIndex){ %gAT\R_f
setPageSize(PAGESIZE); ka\{?:r,8
setTotalCount(totalCount); {> msE }L
setItems(items); j_N<aX
setStartIndex(startIndex); Z,E$4Z
} Dn 0L%?_
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public PaginationSupport(List items, int }" vxYB!h3
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totalCount, int pageSize, int startIndex){ [=q/f2_1.
setPageSize(pageSize); n2B%}LLa
setTotalCount(totalCount); P{6$".kIY
setItems(items); PD0&ep1h7G
setStartIndex(startIndex); hDJG.,r
} jo<xrn\
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publicList getItems(){ ^py=]7[I
return items; rBTg"^jsw
} :) lG}c
@NRN#~S,_]
publicvoid setItems(List items){ },l
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this.items = items; 3u/JcU-<
} Gd%i?(U,R
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publicint getPageSize(){ ?IHt T3'Rt
return pageSize; /x ?@Mn>
} {f#QZS!E
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publicvoid setPageSize(int pageSize){ S9Yzvq!(
this.pageSize = pageSize; L?d?O
} M0fN[!*z
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publicint getTotalCount(){ "@eGgQ
return totalCount; :$b` n
} T(?w}i
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publicvoid setTotalCount(int totalCount){ 7! >0
if(totalCount > 0){ F(ydqgH~a
this.totalCount = totalCount; Z&Ob,Ru
int count = totalCount /
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pageSize; {q)d
if(totalCount % pageSize > 0) V
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count++; ):G%o
indexes = newint[count]; UXBWCo;-
for(int i = 0; i < count; i++){ 0* F` h
indexes = pageSize * aKriO
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i; \nEMj,)
} YQN:&Cls
}else{ l|WFS
this.totalCount = 0; (Ut8pa+yX
} p [C
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} D5c
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publicint[] getIndexes(){ %jjPs.
return indexes; 9-T<gYl
} 2]mV9B
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publicvoid setIndexes(int[] indexes){ T5u71C_wmt
this.indexes = indexes; EN2t}rua
} \PxT47[@e
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publicint getStartIndex(){ RdPk1?}K
return startIndex; r5~W/eE
} X=whZ\EZ
@6'~RD.
publicvoid setStartIndex(int startIndex){ !{^kH;*u
if(totalCount <= 0) dHIk3j-!
this.startIndex = 0; `CVkjLiy
elseif(startIndex >= totalCount) We{@0K/O
this.startIndex = indexes jvB[bS`<H
/X_L>or
[indexes.length - 1]; ~wDXjn"U&
elseif(startIndex < 0) BFW b0;+
this.startIndex = 0; d MR?pbD
else{ $!*>5".A
this.startIndex = indexes 9s"st\u
4
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[startIndex / pageSize]; |;US)B8}*Z
} $~6MR_Yq
} .1[.f}g$J
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publicint getNextIndex(){ ,)[9RgsE
int nextIndex = getStartIndex() + 7_2D4CI
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pageSize; F NPu
if(nextIndex >= totalCount) SQ,-45@W
return getStartIndex(); jlP*RX
else )oCL![^pXe
return nextIndex; \B4H0f
} `TJhH<z"%
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publicint getPreviousIndex(){ SvSO?H!-
int previousIndex = getStartIndex() - i-wRwl4aEF
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pageSize; ! :]_-DX
if(previousIndex < 0) `;}`>!8j
return0; Acw`ytV
else #4m5I="
return previousIndex; eV*QUjS~
} F&6#j
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} 06&;GW!-
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抽象业务类 anW['!T9{s
java代码: n0 l|7:Mk
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/** 6HCg<_j]
* Created on 2005-7-12 y7UU'k`
*/ (@}^ 3jpT
package com.javaeye.common.business; H7+z"^s*
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import java.io.Serializable; aaU4Jl?L
import java.util.List; VvW4!1Dl
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import org.hibernate.Criteria; k4$zM/ob
import org.hibernate.HibernateException; 5b"=m9{g
import org.hibernate.Session; =Lkn
import org.hibernate.criterion.DetachedCriteria; W\Pd:t
import org.hibernate.criterion.Projections; -E\G3/*51
import qe&|6 M!
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org.springframework.orm.hibernate3.HibernateCallback; !f(A9V
import cV>?*9z0
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org.springframework.orm.hibernate3.support.HibernateDaoS YMu#<ZG
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upport; PFpFqJ)Cs"
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import com.javaeye.common.util.PaginationSupport; O;4S<N
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public abstract class AbstractManager extends )*}\fmOv{
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HibernateDaoSupport { QswPga(-
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privateboolean cacheQueries = false; H%m^8yW1
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privateString queryCacheRegion; &c-V
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publicvoid setCacheQueries(boolean xytWE:=
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cacheQueries){ f
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this.cacheQueries = cacheQueries; 4wKCzPy
} e;=R8i
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publicvoid setQueryCacheRegion(String ])y)]H#{
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queryCacheRegion){ gAvNm[=wD2
this.queryCacheRegion = /|U;_F Pmc
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queryCacheRegion; w$$pTk|&n
} ]NaH *\q
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publicvoid save(finalObject entity){ /b{@']
getHibernateTemplate().save(entity); nZj&Ma7R
} Kc]
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publicvoid persist(finalObject entity){ TQt[he$O
getHibernateTemplate().save(entity); evEdFY
} L7 FFa:#
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publicvoid update(finalObject entity){ b6e2a/x
getHibernateTemplate().update(entity); 1 h(n}u
} 6G4~-_
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publicvoid delete(finalObject entity){ 9_*3xu<7i
getHibernateTemplate().delete(entity); lnl>!z
} 4%v-)HGh
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publicObject load(finalClass entity, ve/.q^JeJ
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finalSerializable id){ }cW8B"_"
return getHibernateTemplate().load U>n.+/ss
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(entity, id); Rwj
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} 1iqgTi>
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publicObject get(finalClass entity, &_QD1 TT
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finalSerializable id){ L eUp!
return getHibernateTemplate().get B_c-@kl
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(entity, id); sN[<{;K4
} xjDaA U,
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publicList findAll(finalClass entity){ >4lA+1JYk
return getHibernateTemplate().find("from 'Um\m
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" + entity.getName()); 's8LrO(=
} PVq y\i
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publicList findByNamedQuery(finalString >\Iy <M
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namedQuery){ z\J#d 1e
return getHibernateTemplate {y!77>Q/
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().findByNamedQuery(namedQuery); vf<Tq
} +P*,i$MV
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publicList findByNamedQuery(finalString query, rYyEs
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finalObject parameter){ 9jUm0B{?
return getHibernateTemplate @rW%*?$7
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().findByNamedQuery(query, parameter); mhnK{M @56
} =Rf!i78c5
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publicList findByNamedQuery(finalString query, {uO2m*JrI
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finalObject[] parameters){ / ='/R7~
return getHibernateTemplate X@7e7
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().findByNamedQuery(query, parameters); dLu3C-.(
} 6n.C!,Zmn
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publicList find(finalString query){ y$pT5X G
return getHibernateTemplate().find \CE8S+Z%
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(query); !TuMrA*
} y>m=A41:g
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publicList find(finalString query, finalObject -Z%B9ql'
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parameter){ J\kv}v
return getHibernateTemplate().find H`ZUI8-
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(query, parameter); Mi"dFx^Md
} 7L&=z$U@m
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public PaginationSupport findPageByCriteria cw{[% 7
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(final DetachedCriteria detachedCriteria){ Z:}d\~`x$%
return findPageByCriteria _[.3I1kG
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); JB= L\E}
} :X;'37o#q
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public PaginationSupport findPageByCriteria $u./%JS
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(final DetachedCriteria detachedCriteria, finalint miZ&9m
{` Lem
startIndex){ k:0HsN!F9
return findPageByCriteria bO%bMZWB!y
@9^ozgg
(detachedCriteria, PaginationSupport.PAGESIZE, dRXF5Ox5K}
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startIndex); |,89zTk'
} ^H1B62_
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public PaginationSupport findPageByCriteria Zi fAn
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(final DetachedCriteria detachedCriteria, finalint C&m[/PJ~l
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pageSize, Vn-y<*np
finalint startIndex){ r-s.i+\
return(PaginationSupport) lXS.,#lp
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getHibernateTemplate().execute(new HibernateCallback(){ WBgS9qiB
publicObject doInHibernate -Fe))Y'=
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(Session session)throws HibernateException { }0Qex=vkO
Criteria criteria = 3%G>TB
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detachedCriteria.getExecutableCriteria(session); 8(euWS
int totalCount = P"LbWZ6Nj
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((Integer) criteria.setProjection(Projections.rowCount 9"3 7va
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()).uniqueResult()).intValue(); ;x*_h
criteria.setProjection ua%$r[
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(null); F(J6 XnQ
List items = N|OI~boV%
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criteria.setFirstResult(startIndex).setMaxResults |UN0jR
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(pageSize).list(); Lj"@JF;c
PaginationSupport ps = *UVo>;
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new PaginationSupport(items, totalCount, pageSize, S:IhJQ4K
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startIndex); V7Z+@e-5
return ps; kQ5mIJ9(
} u]K&H&AxT
}, true); y3^<rff3Gc
} a\60QlAk~
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public List findAllByCriteria(final +ML4.$lc^
+{(f@,&~{
DetachedCriteria detachedCriteria){ _?"P<3/iF
return(List) getHibernateTemplate z']TRjDbT
"]1 !<M6\i
().execute(new HibernateCallback(){ zPzy0lx
publicObject doInHibernate Ah5`Cnv
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(Session session)throws HibernateException { ~:`5Y"Av:
Criteria criteria = }
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detachedCriteria.getExecutableCriteria(session); vS#Y,H:yAj
return criteria.list(); cEI
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} ME.l{?v
}, true); 1:!_AU?
} F|+Qi BO
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public int getCountByCriteria(final 1b^e4
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DetachedCriteria detachedCriteria){ 99<]~,t=5
Integer count = (Integer) &8p]yo2zO
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getHibernateTemplate().execute(new HibernateCallback(){ uX82q.u_y
publicObject doInHibernate PIk2mX/D_6
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(Session session)throws HibernateException { Qt-7jmZw1
Criteria criteria = \9
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detachedCriteria.getExecutableCriteria(session); WC&V9Yk
return 6,wi81F,}
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criteria.setProjection(Projections.rowCount R[#Np`z
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()).uniqueResult(); O`?qnNmc;
} ^/6LVB *
}, true); JM&`&fsOC{
return count.intValue(); eELLnU{"
}
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} !uZ)0R
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用户在web层构造查询条件detachedCriteria,和可选的 ;AH8/M B9
> J.q3
startIndex,调用业务bean的相应findByCriteria方法,返回一个 hkpS}*L9o
Z= +Tw!wR>
PaginationSupport的实例ps。 3VZ}5
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ps.getItems()得到已分页好的结果集 vRhI:E)So#
ps.getIndexes()得到分页索引的数组 '048Qykt;
ps.getTotalCount()得到总结果数 ,kQCCn]
ps.getStartIndex()当前分页索引 YD9|2S!G
ps.getNextIndex()下一页索引 H\%^n<]#
ps.getPreviousIndex()上一页索引 C1`fJhy
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <B
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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 !#Pr'm/,mu
cy64xR BB
一下代码重构了。 *ZkOZ
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我把原本我的做法也提供出来供大家讨论吧: u0Bz]Ux/Q
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首先,为了实现分页查询,我封装了一个Page类: @ N@
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java代码: 'u#c_m!9
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/*Created on 2005-4-14*/ \ nUJ)w
package org.flyware.util.page; #e[S+a
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/** s7(1|}jh
* @author Joa HPY;UN
* kr\#CW0?
*/ V
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publicclass Page { ctoh&5%!n+
2"QcjFW%
/** imply if the page has previous page */ l(pP*2
privateboolean hasPrePage; %0zp`'3Y
Nh01NY;
/** imply if the page has next page */ 12V-EG i
privateboolean hasNextPage; ro+8d
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/** the number of every page */ 9T\\hM)k
privateint everyPage; <M,<|Y*)
z:8ieJ)C
/** the total page number */ ^)o#/"JA
privateint totalPage; t~|`RMn"
gDjAnz#
/** the number of current page */ 5`6U:MDq
privateint currentPage; Us\Nmso
z
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/** the begin index of the records by the current ` Nv1sA#C
!TN)6e7`
query */ y\n#`*5k
privateint beginIndex; jItVAmC=i
A>frf[fAW
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/** The default constructor */ pI1g<pe
public Page(){ #"-DE-I[
_U
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} tqpSir
R1Fcd@DWD
/** construct the page by everyPage ;3iWV"&_A
* @param everyPage 7e[&hea
* */ FzF#V=9lP
public Page(int everyPage){ SB:z[kfz|
this.everyPage = everyPage; lm*C:e)4A
} ?weuq"*a
k&:~l@?O
/** The whole constructor */ hP_{$c{4:g
public Page(boolean hasPrePage, boolean hasNextPage, s6D Pb_,
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int everyPage, int totalPage, paUJq?Af
int currentPage, int beginIndex){ 4 g8t
this.hasPrePage = hasPrePage; 8mC$p6Okd
this.hasNextPage = hasNextPage; Z^ .qX\<M
this.everyPage = everyPage; sfp.> bMj
this.totalPage = totalPage; Bw.?Me)mf|
this.currentPage = currentPage; (e32oP"
this.beginIndex = beginIndex; wS [k}
} >}r
1A
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/** }:\e"Bfv
* @return KcM+8W\
* Returns the beginIndex. ?SX0e(+}}
*/ ;I>77gi`]
publicint getBeginIndex(){ zX8{(
return beginIndex; LbnF8tj}h
} 7U-?Rd
@9g!5dcT
/** #B__-"cRv
* @param beginIndex MNX-D0`g
* The beginIndex to set. 787}s`,}
*/ !/Wv\qm
publicvoid setBeginIndex(int beginIndex){ UO'X"`
this.beginIndex = beginIndex; \V*E:_w*
} %sS7o3RW\
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/** Jh%k:TrBm
* @return ^ |>)H
* Returns the currentPage. aT=V/Xh}d
*/
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publicint getCurrentPage(){ y9Q"3LLic`
return currentPage; BtP*R,>
} ^j'vM\^`ml
@"`{Sh`Y$
/** (d-j/v*4
* @param currentPage W97
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* The currentPage to set. ~wd~57i@
*/ !7anJl
publicvoid setCurrentPage(int currentPage){ =Y5*J#
this.currentPage = currentPage; |Vc:o_n7
} \8SHX
h_h6@/1l
/** EB>rY
* @return /J'dG%
* Returns the everyPage. .g6(07TyV
*/ {%z}CTf#
publicint getEveryPage(){ "O{:jfq
return everyPage; f%Bm x{Ttq
} N%`Eq@5
QX393v!
/** UjQi9ELoJ
* @param everyPage 0)3*E)g{
* The everyPage to set. -\=kd {*B
*/ 5>[j^g+@
publicvoid setEveryPage(int everyPage){ AT,?dxP J
this.everyPage = everyPage; &:*|K xX
} [+v}V ,jb
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/** {piZm12q?
* @return Fu!sw]6xx
* Returns the hasNextPage. EYF]&+ 9
*/ ]Q\/si&
publicboolean getHasNextPage(){ &\o!-EIK8
return hasNextPage; :j0r~*z-
} EJ3R{^
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/** yasKU6^R'
* @param hasNextPage Sud5F4S
* The hasNextPage to set. S}cm.,/w
*/ ua
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publicvoid setHasNextPage(boolean hasNextPage){ SpUcrK;1
this.hasNextPage = hasNextPage; oXkxd3
} ~8G<Nw4*\
8TnByKZz
/** D;al(q
* @return KI="O6 h
* Returns the hasPrePage. ]%5DuE\M8\
*/ Kr]`.@/.S
publicboolean getHasPrePage(){ eqze7EY
return hasPrePage; pB;p\9A*q
} -*EK-j
0oi
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/** nn_j"Nu
* @param hasPrePage nUvxO `2
* The hasPrePage to set. V/G'{ q
*/ ]l'W=_XDg
publicvoid setHasPrePage(boolean hasPrePage){ 'L2M
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this.hasPrePage = hasPrePage; BZE~k?*
} Oj*3'?<7=
!:mo2zA
/** pcw^W
* @return Returns the totalPage. b!ZXQn3X<
* [S/]Vk|4
*/ MD,}-m
publicint getTotalPage(){ lc=C
return totalPage; #U NTD4
} 8 JUUK(&Z
.sA?}H#wb
/** g(Jzu'
* @param totalPage gHC -Y 0_
* The totalPage to set. gC#PqK~
*/ 5xi f0h-`
publicvoid setTotalPage(int totalPage){ vb}; _/#?
this.totalPage = totalPage; Q-%Q7n'c
} V>j6Juh
P.RlozF5;
} vvLm9Tw
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D
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 0!rU,74I=
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个PageUtil,负责对Page对象进行构造: Nf>1`eP
java代码: Pt?]JJxl-
AyKaazm]9
qbkvwL9
/*Created on 2005-4-14*/
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package org.flyware.util.page; \CL |=8[2
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import org.apache.commons.logging.Log; |8h<Ls_
import org.apache.commons.logging.LogFactory; UcDJ%vI
zqqpBwk#
/** uYS?# g
* @author Joa pFGK-J
* EW1L!3K
*/ W?G4\ubM3<
publicclass PageUtil { (j+C&*u
fM_aDSRa!H
privatestaticfinal Log logger = LogFactory.getLog cU5x8[2
@dcT8 YC
(PageUtil.class); YcGSZ0vQ
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/** '!Vn
* Use the origin page to create a new page er^z:1'
* @param page dh%C@n:B
* @param totalRecords x$AF0xFO
* @return +M
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*/ ;'dw`)~jQ
publicstatic Page createPage(Page page, int 6!/e_a
$# @G!
totalRecords){ SZ~Ti|^
return createPage(page.getEveryPage(), X_|8CD-@6
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page.getCurrentPage(), totalRecords); R*E/E
} D*`|MzlQ
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/** RP7e)?5$s
* the basic page utils not including exception 18Pc4~>0
>c\'4M8Cz
handler T%KZV/
* @param everyPage 6t
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* @param currentPage -Duy:C6W
* @param totalRecords F^IYx~:
* @return page Dz]&|5'N
*/ I_'S|L
publicstatic Page createPage(int everyPage, int e1S |&W8
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currentPage, int totalRecords){ j.sxyW?3
everyPage = getEveryPage(everyPage); B=7bQli}
currentPage = getCurrentPage(currentPage); z*YkD"]B
int beginIndex = getBeginIndex(everyPage, g[44YrRD
L"1UUOKy
currentPage); N/TUcG|m\
int totalPage = getTotalPage(everyPage, B1JdkL 3h
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totalRecords); @xmO\
boolean hasNextPage = hasNextPage(currentPage, bAeC=?U
+e`f|OQ
totalPage); p8oOm>B96n
boolean hasPrePage = hasPrePage(currentPage); j =r`[Bm
^vYH"2
returnnew Page(hasPrePage, hasNextPage, 9loWh5_1Z
everyPage, totalPage, 4g b2$" !
currentPage, vJ7I
[Z
7qA0bUee5
beginIndex); U voX\
} rBkLwJ]
:mXc|W3
privatestaticint getEveryPage(int everyPage){ 4cRF3$amd
return everyPage == 0 ? 10 : everyPage; ?5Wj y
} #gMMhB=
n&D<l '4
privatestaticint getCurrentPage(int currentPage){ 3DV';
return currentPage == 0 ? 1 : currentPage; ,fpu@@2
} <MB]W`5
xKWqDt
privatestaticint getBeginIndex(int everyPage, int X,IjM&o"Y
>E|@3g
+2
currentPage){ [pUw(KV2m
return(currentPage - 1) * everyPage; \6-x~%xK
} @HxEp;*NH"
+J}
wYind
privatestaticint getTotalPage(int everyPage, int &W-L`aFd0
dQYb)4ir
totalRecords){ 8V >j-C
int totalPage = 0; KoRJ'WW^
K:Wxx"
if(totalRecords % everyPage == 0) G+stt(k:
totalPage = totalRecords / everyPage; k*(c8/<.d
else "=@b>d6U+
totalPage = totalRecords / everyPage + 1 ; "X T7;!
l
Q]&:%^\
return totalPage; :6S!1roi
} '$YB
-
HYyO/U9z|I
privatestaticboolean hasPrePage(int currentPage){ 1uZ[Ewl]
return currentPage == 1 ? false : true;
H;s
} btHN
{a\O7$A\F
privatestaticboolean hasNextPage(int currentPage, k__i Jsk
&PVos|G
int totalPage){ lYmqFd~p
return currentPage == totalPage || totalPage == f uQbDb&
<`k\kZM
0 ? false : true; Xf!@uS6<X
} 4z#{nZG
9] fhH
+%Q:
} #no~g(!o
T]-yTsto
?%%
'GX
d9>*a$x;/
8@]*X,umc
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 l*>t@:2J
BZejqDr*
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 w`=_|4wFw
Gdmh#pv
做法如下: IROX]f}r (
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W2/FGJD
d~F`q7F'?]
的信息,和一个结果集List: =M'M/vKD
java代码: ^]l^q'?>:
z%$ E6Im
:f%FM&b
/*Created on 2005-6-13*/ W&CQ87b
package com.adt.bo; (;v)0&h
Lh3>xZy"-z
import java.util.List; _a1 =?
@)PA9P |
import org.flyware.util.page.Page; ?T=]?[
Atsi}zTR\
/** t\~lGG-p
* @author Joa ]T|9>o!
*/ :MeshzWK
publicclass Result { !`=ms1%U
ALvj)I`Al
private Page page; e~R;
2bk
Vij P;
private List content; ^?PU:eS
Rs_0xh
/** NbOeF7cq+
* The default constructor [
[]'U'
*/
)Y%>t
public Result(){ vvA=:J4/i)
super(); M
S
3?#b
} Y<|!)JLB2
@(>XSTh9
/** 5\93-e
* The constructor using fields }L
Q9db1
* Ci%u =%(
* @param page 272j$T
* @param content ,XT#V\qne
*/ @3`:aWda
public Result(Page page, List content){ Ow7NOhw
this.page = page; U'^AJ2L8
this.content = content; tHNvb\MR$
} 7sP;+G
tP; &$y.8
/** V3;4,^=6Dd
* @return Returns the content. &qw7BuF
*/ iVq4&X_x
publicList getContent(){ XL[/)lX{
return content; { 3``T o$
} aE}1~`
zJ{?'kp
/** 6#~"~WfPQ
* @return Returns the page. tX;00g;U.
*/ }~P%S(zB
public Page getPage(){ %bI(
return page; [NcS[*qp
} \PS{/XK
3wXmX
/** ;\`~M
* @param content t~pA2?9@
* The content to set. !:e|M|T'I*
*/ !_GY\@}
public void setContent(List content){ K/RQ-xd4
this.content = content; =PHl|^
} DO<eBq\O
wu?ahNb.`Y
/** pAS!;t=n,
* @param page
#.O,JG#H
* The page to set. /UeLf$%ZW
*/ ';`fMcN
publicvoid setPage(Page page){ /x.TF'Z*
this.page = page; ||v=in
} \~xI#S@
} w?CbATQ
r})2-3ZA9
f])?Gw
C("PCD
}aYm86C]
2. 编写业务逻辑接口,并实现它(UserManager, "cjZ6^Hum
Lm+!/e
UserManagerImpl) .d`+#1Ot(
java代码: pTq,"}J!+
?7-#iC`
sh.xp8^)^>
/*Created on 2005-7-15*/ \C.%S +u
package com.adt.service; Q0~5h?V'
,2S
<#p!
import net.sf.hibernate.HibernateException; U`q[5U"
2{s ND
import org.flyware.util.page.Page; 1wUZ0r1'
Sp)KtMV
import com.adt.bo.Result; eux_tyC
A/N*Nc
/** nPq\J~M
* @author Joa G],+?E_,
*/ THHrGvb
publicinterface UserManager { S-Va_t$
Qo
public Result listUser(Page page)throws RBx`<iBe
o^~6RZ
HibernateException; b
qB[vPsI
4,9AoK)yp
} l^xkXj
DGY#pnCu
T\c;Ra
FcIH<_r
3M{!yPlj
java代码: Bir}X
zcJ]US
qt]QO1pAd
/*Created on 2005-7-15*/ iMx+y5O
package com.adt.service.impl; !|_
CXm
T|
o0 -e,F>u
import java.util.List; ,- ]2s_
GQqw(2Ub}
import net.sf.hibernate.HibernateException; V.WfP*~NJ
qU8UKI P
import org.flyware.util.page.Page; w GZ(bKyO
import org.flyware.util.page.PageUtil; x+B~ t4A
ulfpop*2
import com.adt.bo.Result; +lJuF/sS8m
import com.adt.dao.UserDAO; :&yRvu
import com.adt.exception.ObjectNotFoundException; ,b>cy&ut
import com.adt.service.UserManager; _if&a'
p8s2#+/
/** :Tuy]]k
* @author Joa hD<z^j+
*/ i?=3RdP/R1
publicclass UserManagerImpl implements UserManager { miS+MK"
?]fBds=
private UserDAO userDAO; BT>*xZLpS
^'EEry
/** ^\N2
Iu>6
* @param userDAO The userDAO to set. 0IDHoNaT<
*/ 7vr)JT=
publicvoid setUserDAO(UserDAO userDAO){ 1bzPBi
this.userDAO = userDAO; *XH?|SV
} Jr17pu(t
KH pxWq
/* (non-Javadoc) "vLqYc4$
* @see com.adt.service.UserManager#listUser @1n0<V/
F!]UaEmV
(org.flyware.util.page.Page) v@>hjie
*/ !YJdi~q
public Result listUser(Page page)throws "6Dz~5
DP;B*s4{U
HibernateException, ObjectNotFoundException { Y2<#%@%4
int totalRecords = userDAO.getUserCount(); Fg#*rzA
if(totalRecords == 0) Yf {s0Z
throw new ObjectNotFoundException $Z{ fKr
EVq<gGy
("userNotExist"); /2l4'Q=
page = PageUtil.createPage(page, totalRecords); 1&jX~'
List users = userDAO.getUserByPage(page); ?-@hNrx
returnnew Result(page, users); [*}[W6
3v
} 1Za\T?V
/c'#+!19
} f7s]:n*Ih
|{9"n<JW
2YwV}
JC =Bxv
6 Dg[b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 HwU \[f
W;KHLHp-
询,接下来编写UserDAO的代码: t4gD*j6J3
3. UserDAO 和 UserDAOImpl: e'\I^'`!M
java代码: f2{4Y)
$ng\qJ"HF
3I"&Qp%2
/*Created on 2005-7-15*/ -q+Fj;El
package com.adt.dao; /AMtT%91
gpw(j0/Fs
import java.util.List; B1LnuB%
L3<XWpv
import org.flyware.util.page.Page; 2iH,U
}*R"yp
import net.sf.hibernate.HibernateException; |Cen5s
W&
Upv2s:wa}z
/** a#raUF7e
* @author Joa zZf#E@=$|
*/ pnqjATGU
publicinterface UserDAO extends BaseDAO { B]Zsn`n
RsV<*s
publicList getUserByName(String name)throws +u)'
QPFpGS{d
HibernateException; 8L|C&Ymj
R#T6Ii
publicint getUserCount()throws HibernateException; ~Yr.0i.W
(+^1'?C8
publicList getUserByPage(Page page)throws Jhj]rsGk
Ko%rB+d
HibernateException; -_4! id
,U7hzBj8k
} 8wy"m=>=b}
'.dW>7
gq0gr?
P0z "Eq0S
1gt[_P2u
java代码: FcWu#}.p}
_n_i*p
'2
WYh7Y
/*Created on 2005-7-15*/ QU#/(N(U#T
package com.adt.dao.impl; ~z'0~3
3 $kZu
import java.util.List; XG[%oL
-[7.VP
import org.flyware.util.page.Page; t)m4"p7
X:e'@]Z)?
import net.sf.hibernate.HibernateException; @=,J6
import net.sf.hibernate.Query; ~j4=PT
HwGtLeB"
import com.adt.dao.UserDAO; AVJF[t ,
3n/L;T,X
/** *o>E{
* @author Joa %kUJ:lg;d
*/ [cH/Y2[
public class UserDAOImpl extends BaseDAOHibernateImpl 1rKR=To
P9'5=e@jB
implements UserDAO { ;zOZu~Q|'
3gM{lS}h#
/* (non-Javadoc) m:^@AR1%d
* @see com.adt.dao.UserDAO#getUserByName fSP~~YSeU
"d#s|_n,d)
(java.lang.String) >:xnjEsi$/
*/ XmnqZWB
publicList getUserByName(String name)throws t #AQD]h
U-k;kmaj
HibernateException { |-R::gm
String querySentence = "FROM user in class ,S8Vfb &
cn#a/Hx
com.adt.po.User WHERE user.name=:name"; PQ[TTLG\&
Query query = getSession().createQuery P``hw=L
K1hw'AaQ
(querySentence); _x
\Ll?,
query.setParameter("name", name); -Rvxjy)[N
return query.list(); y,
Z#?O
} H z6H,h
Dxe|4"%^
/* (non-Javadoc) 646yeQ1
* @see com.adt.dao.UserDAO#getUserCount() l&rDa=m.J
*/ xvkof
'Q)
publicint getUserCount()throws HibernateException { WLpn,8qsY
int count = 0; SN+Bmdup
String querySentence = "SELECT count(*) FROM zPmVECS
,'9tR&S$_
user in class com.adt.po.User"; Cam}:'a/`
Query query = getSession().createQuery S ~_%
A`r9"([-A
(querySentence); daorKW4
count = ((Integer)query.iterate().next l=oVC6C
<r kW4
()).intValue(); D6vn3*,&
return count; 9t[278B6
} 8 N` $7^^
"VeUOdNA>
/* (non-Javadoc) .~8+s.y
* @see com.adt.dao.UserDAO#getUserByPage d{he
=6dKC_Q
(org.flyware.util.page.Page)
cjR.9bgn
*/ ^M9oTNk2
publicList getUserByPage(Page page)throws 2mO#vTX4
+wSm6*j7=
HibernateException { pxbNeqK@p
String querySentence = "FROM user in class 2%8Y-o?
Lwcw%M]
com.adt.po.User"; aC},h
Query query = getSession().createQuery pd1m/:
YUb,5Y0
(querySentence); [w/t
query.setFirstResult(page.getBeginIndex()) {Y"r]:5i
.setMaxResults(page.getEveryPage()); 8?YW i
return query.list(); ##@#:B
} ~
t
H s+
`Y;gMrp
} /RC!Yi
9/M!S[N9
-X[[
OR9+
&-:yn&f7
nc~d*K\!
至此,一个完整的分页程序完成。前台的只需要调用 hyKg=Foq
gk1S"H
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?<?C*W_
f5% &
的综合体,而传入的参数page对象则可以由前台传入,如果用 gJxVU41
\,!q[nC
webwork,甚至可以直接在配置文件中指定。 D:E_h
Bqi2n'^O2
下面给出一个webwork调用示例: 3x0wk9lND
java代码: #6jwCEo=V
}hitU(5t0
b=UMoWS
/*Created on 2005-6-17*/ bJF/daC5
package com.adt.action.user; *UoHzaIqz
a.IF%hP0xo
import java.util.List; bMZn7c
|a$w;s>\
import org.apache.commons.logging.Log; .GN$H>')
import org.apache.commons.logging.LogFactory; !s*''v*
import org.flyware.util.page.Page; (I
ds<n"
t/WnDR/fM
import com.adt.bo.Result; Gy6qLM
import com.adt.service.UserService; i;zGw.;Q
import com.opensymphony.xwork.Action; yO;C3q
o;>3z*9?3
/** )UZ0gfx
* @author Joa NND=Zxl
*/ fKz"z{\,0
publicclass ListUser implementsAction{ \e8*vos
KBRg95E~]l
privatestaticfinal Log logger = LogFactory.getLog nl9Cdi]o
\seG2vw$
(ListUser.class); F2`htM@,
kqvJ&7
private UserService userService; 0 ;_wAk
j$8|ym^OX
private Page page; d<Q+D1
Y`7#[g
privateList users; o+_/)c
Ipz
1+
#s'
/* 9g
&Ch9-/
* (non-Javadoc) uWB:"&!^
* 7{^4 x#NO
* @see com.opensymphony.xwork.Action#execute() nN`Z0?
*/ wvmg)4,
publicString execute()throwsException{ >6[ X }
Result result = userService.listUser(page); *Qg5Z
page = result.getPage(); }K/}(zuy1Y
users = result.getContent();
!jnqA Z
return SUCCESS; Z0ncN])
} -RH4y 2
RCh$j&Tn
/** Wz-3?EQ
* @return Returns the page. (' Ko#3b
*/ ~1=.?Ho
public Page getPage(){ 1t[;` iZ
return page; iRUR4Zs
} T018)WrhL
2z.8rNwT
/** c{,y{2c]LT
* @return Returns the users. H-_^TB
*/ Ld\LKwo
publicList getUsers(){ }$Hs;4|
return users; UH 47e
} ']ITuP8
(:?5 i`
/** Z6IJ o%s
* @param page 8tLT'2+H#
* The page to set. }fJ:wku
*/ ~U"by_
publicvoid setPage(Page page){ 3?.1~ "-J
this.page = page; U]V3DDN
} M<{5pH(K
;wJ7oj<
/** 5\akI\
* @param users 5)d,G9
* The users to set. x|@1wQ"6
*/ r,2Xu
publicvoid setUsers(List users){ Gur8.A;Y
this.users = users; {cR_?Y@
} ~\IF9!
6R 1wn&8
/** KTG:I@|C
* @param userService aBXYri
* The userService to set. 2BoFyL*
*/ IajD;V
publicvoid setUserService(UserService userService){ 4Qa@`
this.userService = userService; E4sn[DO
} pU?{0xZH
} NuC-qG#
V";mWws+?#
H$z>OS_6U
m b%C}8D
:3f-9aRC!
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, F(Lb8\to\M
i{o#3
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 .:w#&yM [U
.)LZ`Ge3F
么只需要: r_b8,I6{]
java代码: $ q%mu
@SU8 \:(U
F(#ha J$>
<?xml version="1.0"?> 3>RcWy;1i
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2 ]L=s3
h/,R{A2mO
1.0//EN" "http://www.opensymphony.com/xwork/xwork- aXMv(e+
'S =sj}X
1.0.dtd"> cNe0x2Z$?
Z}|TW~J=
<xwork> 30D:ZmlY
qs=Gj?GwGQ
<package name="user" extends="webwork- a
"R7JjH
Vwjk[ DOL
interceptors"> =v.{JV#
BbFa=H.
<!-- The default interceptor stack name ]JH64~a
1Fv8T'
--> FC6x Fg^
<default-interceptor-ref +}P%HH]E/p
k!T|)\nc+
name="myDefaultWebStack"/> Odm#wL~E
zG_p"Z7,
<action name="listUser" k^z0Lo|)'
"jT#bIm
class="com.adt.action.user.ListUser"> l09Fn>wa
<param tE@FvZC'=
R,%_deV\(
name="page.everyPage">10</param> <$%ql'=
<result 2Zy_5>~
3?Lgtkb8
name="success">/user/user_list.jsp</result> Pg`JQC|
</action> mb&lCd^-
v,{h:
</package> ^=^$tF
PY?8[A+
</xwork> 8!&nKy<Y
:}Ok$^5s
uMvb-8
3V?817&6z
6gnbkpYi
[F+,YV%t
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 =Q-k'= 6\
V>Fesm"aq
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。 }k7_'p&yk
*:g_'K"+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 #jBN?Z#
oaK.kOo
}# Doy{T
OUI6
ax\[
: lgi>^
我写的一个用于分页的类,用了泛型了,hoho ='}#`',
G(/DtY]
java代码: }^Gd4[(,g
[k$efwJ
9[VxskEh
package com.intokr.util; 2/B)O)#ls
>zs5s
import java.util.List; e4\dpvL
ZSB?Y1wG
/** Y.sz|u 1
* 用于分页的类<br> GS;%zdH~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $i#?v
* E7nFb:zlV
* @version 0.01 8AL\ST51x"
* @author cheng 'c %S!$P
*/ fPqr6OYz
public class Paginator<E> { Q`ME@vz
privateint count = 0; // 总记录数 I4=Xb^Ux
privateint p = 1; // 页编号 X(Qu{HhI
privateint num = 20; // 每页的记录数 *jITOR!uF`
privateList<E> results = null; // 结果 =:=/Gz1
fThgK;Qy'U
/** jVWK0Zba
* 结果总数 ^U@~+dw
*/ Udgqkl
publicint getCount(){ 3<:jx~y>
return count; gb" 4B%Hm
} Kct@87z
]Oeh=gq
publicvoid setCount(int count){ $_Nf-:D*
this.count = count; {ci.V*:"
} &7>zURv
/7"I#U^u/
/** F<|t\KOW
* 本结果所在的页码,从1开始 7DD&~ZcD
* C! 9}
* @return Returns the pageNo. zjl!9M!
*/ [?0d~Q(R#
publicint getP(){ 9902+pW
return p; 6.WceWBR
} eWs&J24
8LzBh_J?
/** kz}R[7
* if(p<=0) p=1 jgv`>o%<W
* nz]&a1"&
* @param p YJeyIYCs<
*/ C[sh,
publicvoid setP(int p){ EgjR^A1W2
if(p <= 0) LeOP;#
p = 1; k[j90C5
this.p = p; [iP#VM-N
} I:98 $ r$
qet>1<
/** Ifc]K?
* 每页记录数量 W/$Zvl
*/ }_9,w;M$
publicint getNum(){ W-Hoyn>?2
return num; 58Xzup_"
} 2_^aw[-
r!1D*v5&:
/** 46@{5)Tq
* if(num<1) num=1 9;.(u'y|
*/ ElhRF{R
publicvoid setNum(int num){ \_V-A f{6
if(num < 1) !E8X~DJ
num = 1; G2bDf-1ew
this.num = num; Fb22p6r
} ~}EMk 3
GPz(j'jU
/** P262Q&.}d
* 获得总页数 tG vG
*/ _|[UI.a
publicint getPageNum(){ eV:9y
return(count - 1) / num + 1; !* Ti}oIo&
} c#-U%qZ
'm1N/)F
/** v\16RD
* 获得本页的开始编号,为 (p-1)*num+1 McH>"`
*/ L37 Y+C//
publicint getStart(){ wN1niR'
return(p - 1) * num + 1; &qpr*17T
} %~L>1ShtU
CYYkzcc^
/** ::Ke^dp
* @return Returns the results. /Jf.y*;
*/ ?0?
R
publicList<E> getResults(){ j
8*ZF
return results; f` =CpO*
} Dd;Nz
1)
ta
public void setResults(List<E> results){ '!l1=cZD
this.results = results; ~|<WHHN(
} .CL^BiD.D
2gO2jJlv
public String toString(){ }ci#>
StringBuilder buff = new StringBuilder C<KrMRWh^
@-UL`+
(); nKW*Y}VO
buff.append("{"); Ee`1F#c
buff.append("count:").append(count); WVVJ
buff.append(",p:").append(p); G}&Sle]
buff.append(",nump:").append(num); iw*Nq,(
buff.append(",results:").append m[j70jYe
M\yT).>z
(results); pZ/>[TP(%F
buff.append("}"); N<QXmgqx
return buff.toString(); `PY>Hgb
} KII *az
K~@Mg1R
} `rf_7
xg)v0y~
z5)s/;Sc