Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 s>ilxLSX]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^i:%0"[*^i
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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 5NHNnDhuL
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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 lG6P+ Z/nf
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分页支持类: @#rF8;
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java代码: l]C#bL>i
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package com.javaeye.common.util; ~qT5F)$B-
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import java.util.List; Dn~c
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publicclass PaginationSupport { jnho*,X
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publicfinalstaticint PAGESIZE = 30; dg-nv]7
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privateint pageSize = PAGESIZE; Bq@_/*'*Y
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privateList items; gM>geWB<
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privateint totalCount; [_PZdIN
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privateint[] indexes = newint[0]; LD/NMb
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privateint startIndex = 0; 4h~CDy%_
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public PaginationSupport(List items, int _Fkz^B*
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totalCount){ e*)*__$O
setPageSize(PAGESIZE); -aPRLHR
setTotalCount(totalCount); |kGj}v3
setItems(items); l$/.B=]
setStartIndex(0); F#=M$j_
} zl $mt'\y
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public PaginationSupport(List items, int P@|
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totalCount, int startIndex){ 3n_N^q}
setPageSize(PAGESIZE); }2%L
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setTotalCount(totalCount); As{ "B
setItems(items);
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setStartIndex(startIndex); > zA*W<g
} mUA!GzJ~u-
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public PaginationSupport(List items, int h(C@IIO^;G
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totalCount, int pageSize, int startIndex){ FJQ=611@
setPageSize(pageSize); Uhs/F:E[A
setTotalCount(totalCount); *{DpNV8"
setItems(items); duQ,6
setStartIndex(startIndex); TAB'oLNp
} '2XIeR
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publicList getItems(){ m)Ta5w^
return items; ghU~H4[x D
} y7^E`LKK
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publicvoid setItems(List items){ i+90##4<?
this.items = items; Z2a~1BL
} cXw8#M!
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publicint getPageSize(){ )s N}ClgJ
return pageSize; 0uL*-/|
} >)^Q p-
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publicvoid setPageSize(int pageSize){ g286
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this.pageSize = pageSize; q?y-s
} { k>T*/
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publicint getTotalCount(){ ;vG%[f`K
return totalCount; 7y4jk
} \&/V p`
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publicvoid setTotalCount(int totalCount){ :lW8f~!
if(totalCount > 0){
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this.totalCount = totalCount; CT?4A1[aD
int count = totalCount / = IJ}b=:
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pageSize; " %
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if(totalCount % pageSize > 0) [>D5(O
count++; |"g+p)A
indexes = newint[count]; R0~w F>
for(int i = 0; i < count; i++){ Z H2
indexes = pageSize * }2h!
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i; LEuDDJ-
} x3:d/>b
}else{ ZiW&*nN?M
this.totalCount = 0; xc}kDpF=g
} f|6 Y
} J\Db8O-/x4
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publicint[] getIndexes(){ &G!~@\tMg
return indexes; #(}'G*
} Dy&{PeE!
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publicvoid setIndexes(int[] indexes){ BdB9M8fM
this.indexes = indexes; LNcoTdv}k
} =%SH2kb
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publicint getStartIndex(){ vM?,#:5
return startIndex; <ivq}(%72
} v]\T&w%9
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publicvoid setStartIndex(int startIndex){ _MWW
if(totalCount <= 0) W[f%m0
this.startIndex = 0; )>tT""yEl
elseif(startIndex >= totalCount) %/2OP &1<
this.startIndex = indexes Lb#PiTJI
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[indexes.length - 1]; `-MCI)Fq_R
elseif(startIndex < 0) &D91bT+L
this.startIndex = 0; ;o158H$gz;
else{ [>LO'}%
this.startIndex = indexes &r+!rL Kp
*4/KK
[startIndex / pageSize]; dTWcn7C
} ):\+%v^
} 5?A<('2
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publicint getNextIndex(){ #+H3b!8=
int nextIndex = getStartIndex() + d*x&Uh[K
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pageSize; d ATAH}r&
if(nextIndex >= totalCount) [HhaBy9
return getStartIndex(); u"Mf xW`
else g_@b- :$Yq
return nextIndex; W=y9mW|p/
} Y() ZM
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publicint getPreviousIndex(){ ymn@1BA8J
int previousIndex = getStartIndex() - Yfx?3
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pageSize; Wr@q+Whq
if(previousIndex < 0) 7)RRCsn
return0; Z+=WICI/2
else \E6 0
return previousIndex; {]%7-4E
} XqGa]/;}
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} #r,!-;^'p
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抽象业务类 Wngc(+6O&
java代码: _q4Yq'dI
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/** W6RjQ1
* Created on 2005-7-12 {8 &=t8,c
*/ >U.7>K
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package com.javaeye.common.business; {N
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import java.io.Serializable; RBHU5]5
import java.util.List; N/[!$B0H@
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import org.hibernate.Criteria; VR'zm\< D
import org.hibernate.HibernateException; ]f5vk
import org.hibernate.Session; K+d{R=s^
import org.hibernate.criterion.DetachedCriteria; Xy}>O*
import org.hibernate.criterion.Projections; b81cq,
import {L
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org.springframework.orm.hibernate3.HibernateCallback; 36Lf8~d4"h
import zCv)%y
(1[Z#y[
org.springframework.orm.hibernate3.support.HibernateDaoS <nK@+4EH"o
~.#57g F"
upport; {b-SK5%]L
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import com.javaeye.common.util.PaginationSupport; xVrLoAw
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public abstract class AbstractManager extends F$'po#
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HibernateDaoSupport { FxT]*mo
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privateboolean cacheQueries = false; $h}w:AV:
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privateString queryCacheRegion; \mZB*k)+
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publicvoid setCacheQueries(boolean )` S5>[6
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cacheQueries){ v?}rA %so
this.cacheQueries = cacheQueries; ;&!QN#_
} 0b<Qs88yd>
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publicvoid setQueryCacheRegion(String a'?LC)^
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queryCacheRegion){ t0za%q!fK<
this.queryCacheRegion = <dAxB$16sT
7+Nl)d:CJ
queryCacheRegion; Jx Kd
} / 8u}VYE
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publicvoid save(finalObject entity){ >[~`rOU*|Y
getHibernateTemplate().save(entity); ztAC3,r]
} BqpJvRJd
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publicvoid persist(finalObject entity){ 6G(K8Q{>
getHibernateTemplate().save(entity); .yHK
} ZXf&pqmG
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publicvoid update(finalObject entity){ mRt/d
getHibernateTemplate().update(entity); :fUNc^\2
} U lCw{:#F
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publicvoid delete(finalObject entity){ l\!`ZhM,
getHibernateTemplate().delete(entity); Fu% n8
} >"z`))9
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publicObject load(finalClass entity, ^W`RBrJay
x_ <,GE@
finalSerializable id){ 3JD"* <zs
return getHibernateTemplate().load 9yu#G7
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(entity, id); Hn/V*RzQ
} zm_8{Rta}
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publicObject get(finalClass entity, vst;G-ys
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finalSerializable id){ s7\Ee-x)s
return getHibernateTemplate().get n?S)H=
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(entity, id); G7KOJZb+D
} d7uS[tKqg
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publicList findAll(finalClass entity){ rT[b ^l}
return getHibernateTemplate().find("from O7od2fV(i7
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" + entity.getName()); V0*MY{x#S
} .&Sjazk0XO
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publicList findByNamedQuery(finalString A'D2uV
U} Pr1
namedQuery){ )EcfEym.>
return getHibernateTemplate e:.D^GFi
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().findByNamedQuery(namedQuery); .eCUvX`$
} dIA1\;@
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publicList findByNamedQuery(finalString query, j9}.U \
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finalObject parameter){ %/}d'WJR
return getHibernateTemplate ?\<Kb|Q
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().findByNamedQuery(query, parameter); ^e80S^
} +O8}twt@
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publicList findByNamedQuery(finalString query, ,o0[^-b<
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finalObject[] parameters){ Ss1&fZoj
return getHibernateTemplate }_Y\6fcd
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().findByNamedQuery(query, parameters); {>Qs+]
} vtzbF1?O
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publicList find(finalString query){ UY)Iu|~0b
return getHibernateTemplate().find
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}!WuJz"
(query); WpkCFp
} Hx9lQ8
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publicList find(finalString query, finalObject /1hcw|cfC
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parameter){ Lf;Uv[^c
return getHibernateTemplate().find Xa$tW%)
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(query, parameter); 5X^`qUSv
} @Dd (
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public PaginationSupport findPageByCriteria 461p 4)
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(final DetachedCriteria detachedCriteria){ 1V]j8
return findPageByCriteria 9 vNz
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); WaiM\h?=#
} ZCDXy
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public PaginationSupport findPageByCriteria "Fxw"I
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(final DetachedCriteria detachedCriteria, finalint G.^^zmsM`
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startIndex){ ,!98VJmr
return findPageByCriteria OV-#8RXJ
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(detachedCriteria, PaginationSupport.PAGESIZE, Wf&i{3z[
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startIndex); W)`H(J
} jVSU]LU E
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public PaginationSupport findPageByCriteria T
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(final DetachedCriteria detachedCriteria, finalint ~b9fk)z!
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pageSize, WwLV^m]
finalint startIndex){ &Z+.FTo
return(PaginationSupport) NDG?Xs [2
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getHibernateTemplate().execute(new HibernateCallback(){ [t]q#+Zs
publicObject doInHibernate n%{oFTLCo
Z}>+!Z
(Session session)throws HibernateException { )2bbG4:N
Criteria criteria = >UV=k :Q
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detachedCriteria.getExecutableCriteria(session); _9z+xl
int totalCount = Fz]!2rt
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((Integer) criteria.setProjection(Projections.rowCount XE;aJ'kt
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()).uniqueResult()).intValue(); 'uLYah
criteria.setProjection (=tu~ ^
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(null); Hnbd<?y
List items = B(pHo&ox
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criteria.setFirstResult(startIndex).setMaxResults I!~3xZ
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(pageSize).list(); XK
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PaginationSupport ps = (FOJHjtkM
inyS 4tb
new PaginationSupport(items, totalCount, pageSize, ?MJ5GVeH
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startIndex); 1<wolTf
return ps; L$; gf_L
} d)v!U+-|'
}, true); WZ
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} >V@,K z1
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public List findAllByCriteria(final ~tqNxlA
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DetachedCriteria detachedCriteria){ PjU.4aZ
return(List) getHibernateTemplate o6S`7uwJ*/
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().execute(new HibernateCallback(){ cqb]LC
publicObject doInHibernate BWsD~Ft
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(Session session)throws HibernateException { |bjLmGb
Criteria criteria = ,jMV
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detachedCriteria.getExecutableCriteria(session); _B\X&!G.
return criteria.list(); V(n3W=#kky
} N{fYO4O
}, true); Y1 6pT
} 4\2~wSr
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public int getCountByCriteria(final Ijs=4f
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DetachedCriteria detachedCriteria){ @%#!-wC-5
Integer count = (Integer) $I90KQB\_
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getHibernateTemplate().execute(new HibernateCallback(){ f2{qj5 K
publicObject doInHibernate #pX +~{
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(Session session)throws HibernateException { jp-]];:aPJ
Criteria criteria = w7_2JS
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detachedCriteria.getExecutableCriteria(session); 2pAshw1G
return :n(!,
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criteria.setProjection(Projections.rowCount C,3yu,'
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()).uniqueResult(); +4Lj}8,
} |b)N;t
}, true); &bS!>_9
return count.intValue(); \fD[Ej
} Hxd^oE
} 69/qH_Y
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用户在web层构造查询条件detachedCriteria,和可选的 7S9Q{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 J*O$)K%Hx
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PaginationSupport的实例ps。 MBH/,Yd
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ps.getItems()得到已分页好的结果集 t9
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ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 YJ^TO\4WM
ps.getStartIndex()当前分页索引 oJTsrc_-
ps.getNextIndex()下一页索引 Nm/Fc
ps.getPreviousIndex()上一页索引 '$n#~/#}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q<cpU'-#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 +C !A@
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一下代码重构了。 &c!=< <5M
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我把原本我的做法也提供出来供大家讨论吧: L"6@3
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首先,为了实现分页查询,我封装了一个Page类: QP e}rQnm
java代码: \;A\ vQ[
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/*Created on 2005-4-14*/ Kv:ih=?
package org.flyware.util.page; Zb7:qe<UN
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/** RFu]vFff
* @author Joa c!%:f^7g
* 'HV}Tr
*/ PF(P"f.?D
publicclass Page { ,uP1U@Cas
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/** imply if the page has previous page */ 1dK^[;v>3
privateboolean hasPrePage; /vB%gqJvX
gU}?Yy
/** imply if the page has next page */ 7M1*SC
privateboolean hasNextPage; ?Y~>H2
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/** the number of every page */ i4"xvLK4
privateint everyPage; FBPT@`~v
a|\_'#
/** the total page number */ \0pJ+@\T9
privateint totalPage; WiL~b
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/** the number of current page */ O ,[aL;v
privateint currentPage; X3Vpxtb
n.y72-&v
/** the begin index of the records by the current AsM""x1Ix
hGF(E*
query */ sh?Dxodp9
privateint beginIndex; N3H!ptn37
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/** The default constructor */ 8X]j;Rb
public Page(){ z@ A5t4+3
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} )x"Z$ jIs
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/** construct the page by everyPage ,Fg&<Be}Jx
* @param everyPage 0r=Lilu{q
* */ s/Wg^(&M
public Page(int everyPage){ r/L3j0
this.everyPage = everyPage; DRVvW6s
} (.!q~G
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/** The whole constructor */ SJ7>*Sa(u$
public Page(boolean hasPrePage, boolean hasNextPage, j&Ayk*
u6jJf@!ws
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int everyPage, int totalPage, Af0E_
int currentPage, int beginIndex){ a@,tf'Sr
this.hasPrePage = hasPrePage; S-yd-MtQp
this.hasNextPage = hasNextPage; xMhR;lKY
this.everyPage = everyPage; YKl!M/
this.totalPage = totalPage; =W ! m`
this.currentPage = currentPage;
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this.beginIndex = beginIndex; foE2rV/Y
} :ykZ7X&
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/** kZGhE2np
* @return /IV:JVT
* Returns the beginIndex. x)vYc36H
*/ ,bmTBZV
publicint getBeginIndex(){ a$t [}D2
return beginIndex; _I|wp<R
} S_2I8G^A
e@^}y4
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/** &[\rnJ?D
* @param beginIndex ZVIBmx
* The beginIndex to set. iJrscy-
*/ OR"n i
publicvoid setBeginIndex(int beginIndex){ +bf%]
this.beginIndex = beginIndex; |klL KX&
} pdnL~sv
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/** PLo.q|%
* @return bJB:]vs$
* Returns the currentPage. =AcbX_[
*/ KS(T%mk\
publicint getCurrentPage(){ sQihyq6U;
return currentPage; J;q3
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} ]P<&CEk
/e{Oqhf[n
/** cS ];?tqrA
* @param currentPage 4N` MY8',
* The currentPage to set. #2HygS
*/ aeBth{
publicvoid setCurrentPage(int currentPage){ 1NOz $fW
this.currentPage = currentPage; 'OX6eY5
} J?%D4AeS]v
^<|If:|
/** qs-:JmA_w
* @return \HK#d1>ox
* Returns the everyPage. :f/ p5c
*/ U-n33ty`H
publicint getEveryPage(){ ax>c&%vo
return everyPage; @fE^w^K7
} cF vGpZ
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/** ki+9Ln;
* @param everyPage /CA)R26G
* The everyPage to set. v@t*iDa?7
*/ 3UN Jj&-`
publicvoid setEveryPage(int everyPage){ >2g CM
this.everyPage = everyPage; ? ! 1uw
} F~l3?3ZV
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/** q75F^AvH
* @return 1@nR.v"$
* Returns the hasNextPage. p6HZ2Q:a
*/ RXWjFv~/
publicboolean getHasNextPage(){ e&0B4wVAQ
return hasNextPage; zw5~|<
} Le3S;SY&
o$-8V:)6d
/** v\MH;DW^Z
* @param hasNextPage )E[5lD61
* The hasNextPage to set. mML^kgy\N
*/ U<6k!Y9ny
publicvoid setHasNextPage(boolean hasNextPage){ dl":?D4H
this.hasNextPage = hasNextPage; 'g=yJ
} ,-b{oS~u
vy"Lsr3
/** ;!~;05^iD
* @return M"9
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* Returns the hasPrePage. G8;S`-D1a,
*/ rf`Br\g8
publicboolean getHasPrePage(){ nL:vRJr-$
return hasPrePage; 4
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} MW4dPoa
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/** 93!a
* @param hasPrePage X
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* The hasPrePage to set. 3x=F
*/ _E30t( _.
publicvoid setHasPrePage(boolean hasPrePage){ k]>k1Mi=
this.hasPrePage = hasPrePage; ;Q"F@v}18
} (%P* rl
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/** H_AV 3
;
* @return Returns the totalPage. VG8rd'Z
* O\D({>
*/ Wig0OZj
publicint getTotalPage(){ "=".ne
return totalPage; \YKh'|04
} H]!y |p
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/** $>h#|?*?
* @param totalPage K4F!?#
* The totalPage to set. ~lF lv+,%
*/ &
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publicvoid setTotalPage(int totalPage){ t~a$|(
9
this.totalPage = totalPage; .y0](
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} n5JB'F)
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} ,m"ztu-
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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 kCwTv:)
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个PageUtil,负责对Page对象进行构造: U.)G#B
java代码: !}PFi T^
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/*Created on 2005-4-14*/ >C-_Zv<!T\
package org.flyware.util.page; c==Oio("
jF3!}*7,
import org.apache.commons.logging.Log; 8x9kF]=
import org.apache.commons.logging.LogFactory; )>Q 2G/@
dq8 /^1P
/** H4m6H)KOG
* @author Joa 23f[i<4e
* PPqTmx5S
*/ j^ _I{
publicclass PageUtil { <?zTnue
h/fCCfO,
privatestaticfinal Log logger = LogFactory.getLog @*uX[)
9V],X=y~
(PageUtil.class); J@GfO\
o
) ]%9Tgn
/** `JE>GZY
* Use the origin page to create a new page Me}TW!GC
* @param page eTF8B<?
* @param totalRecords PD}R7[".>
* @return _RW[]MN3*
*/ psZeu*/r
publicstatic Page createPage(Page page, int bF KPV%`
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~
totalRecords){ +_gT|vlU
return createPage(page.getEveryPage(), S[a5k;8GL
O|>1~^w
page.getCurrentPage(), totalRecords); #c^Q<&B
}
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sv;zvEn;-L
/** ZW?7g+P
* the basic page utils not including exception UTTC:=F+
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handler Wv0'?NL.
* @param everyPage nP3GI:mjL
* @param currentPage |w JZU
* @param totalRecords YF -w=Y6
* @return page HLe^|
*/ aVP|:OAj
publicstatic Page createPage(int everyPage, int >jX
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nF'xV44"
currentPage, int totalRecords){ <c ovApx
everyPage = getEveryPage(everyPage); ~}5Ml_J$,l
currentPage = getCurrentPage(currentPage); h6h1.lZ
int beginIndex = getBeginIndex(everyPage, u3wC}Zo
;-?ZI$
currentPage); {}pqxouE
int totalPage = getTotalPage(everyPage,
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&'7"i~pC
totalRecords); ~+#--BhV
boolean hasNextPage = hasNextPage(currentPage, ?*'$(}r3
uit-Q5@~
totalPage); UNQRtR/
boolean hasPrePage = hasPrePage(currentPage); 4*vas]
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returnnew Page(hasPrePage, hasNextPage, v\Y}(fD
everyPage, totalPage, TJXraQK-=
currentPage, <KwK
tgzs
Z02s(y=k1
beginIndex); 16QbB;
} z`/.v&<>V
#Q3PzDfj
privatestaticint getEveryPage(int everyPage){ Fd[h9 G
return everyPage == 0 ? 10 : everyPage;
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} "F"_G
>Mn>P!
privatestaticint getCurrentPage(int currentPage){ {1MGb%xW
return currentPage == 0 ? 1 : currentPage; uXLZtfu{
} EB>B,#
]zyX@=mM
privatestaticint getBeginIndex(int everyPage, int L)lQ&z?
}[z<iij4
currentPage){ F:J7|<J^F
return(currentPage - 1) * everyPage; s$Zq/l$1x
} %kx
^/DH
!&`\ LJ=j
privatestaticint getTotalPage(int everyPage, int 5$oewjLO
^ MT9n
totalRecords){ ChTXvkdH
int totalPage = 0; ,iVPcza
]&:b<]K3
if(totalRecords % everyPage == 0) nnE_OK!}T
totalPage = totalRecords / everyPage; FxfL+}?Q
else `<J#l;y
totalPage = totalRecords / everyPage + 1 ; v
(ka,Dk3
`x UG|
return totalPage; 3%R{"Q"
} +%wWSZ<#
lKEX"KQ!
privatestaticboolean hasPrePage(int currentPage){ Wu!t C
return currentPage == 1 ? false : true; s^>lOQ=
} N\q)LM !M
iS"8X#[]N
privatestaticboolean hasNextPage(int currentPage, XY{:tR_al
VI24+h'J
int totalPage){ )_8}53C
return currentPage == totalPage || totalPage == S9p?*
h `ME(U~<<
0 ? false : true; BMNr<P2li
} 9&%#nN4`8
n}A?jOSAe
xHB/]Vd-
} GVG!sMmnX
8PBU~mr
r!$'!lCR
9k:W1wgH1
f<89$/w
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。 ^Cg^`n?@b
e3eVvl5]
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 sS2_-X[_
uuSR%KK]|
做法如下: 1OJ*wI*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |mxNUo-
S<nP80C
的信息,和一个结果集List: :p<kQ4
java代码: X0WNpt&h
PW%1xHLfk
b,s Gq
/*Created on 2005-6-13*/ wmo{YS3t|
package com.adt.bo; yGvDn' m
W|dpFh`
import java.util.List; qO-C%p
[5
94|yvh.B
import org.flyware.util.page.Page; r219M)D?
ZBX
/** '@TI48 J+
* @author Joa 9?;@*x
*/ 5VR.o!h3I
publicclass Result { e&QS#k
/vjGjb=3U
private Page page; s=d+GMa
yGiP[d|tRc
private List content; W]]q=c%2
g5#CN:%f
/** $n= O
* The default constructor 84=-Lw
*/ yo'9x
s
public Result(){ X>8-`p
super(); M$Fth*q{GD
} J&eAL3"GF
N = LM?(H
/** 9Ct_$.Q.
* The constructor using fields Xb}!0k/{
* qy_%~c87
* @param page '>3`rsu
* @param content =}JBA>q(
*/ <jeh`g
public Result(Page page, List content){ 6eQsoKK
this.page = page; \M5P+Wk'
this.content = content; Lt1U+o[ot
} $$JIBf8
eZg$AOpU
/** .H8mRvd?
* @return Returns the content. naz:A
*/ ^7u X$
publicList getContent(){ Kax#OYLpg
return content; K@HQrv<
} \a\= gn
JO2xT#V
/** `=79i$,,t
* @return Returns the page. Ap%O~wA'
*/ fk>l{W}e)
public Page getPage(){ Dl%?OG<
return page; 9x=3W?K:,
} S'o ]=&
o{V#f_o
/** bM"fk&
* @param content 2MuO*.9D
* The content to set. ga-{!$b*
*/ HsnG4OE
public void setContent(List content){ \c{R <Hh
this.content = content; uPkb, :6~Z
} Gn59yG!4
u_.HPA
/** ]:&n-&@L
* @param page iJ)0Y~
* The page to set. &<Mt=(qY1
*/ '[nmFCG%m*
publicvoid setPage(Page page){ wcZbmJ:
this.page = page; H"+wsM^@
} exQ#<x*
} &]< 3~6n
==N` !+
66Gx.tE
(SF1y/g@=
Z:@6Lv?CN
2. 编写业务逻辑接口,并实现它(UserManager, R2 lXTW*
|5,<jyp
UserManagerImpl) tMFsA`ng
java代码: h4(JUio
*69c-`o
XJSa]P^B1
/*Created on 2005-7-15*/ R}r~p?(M
package com.adt.service; /b#q*x-b
HzvlF0f
import net.sf.hibernate.HibernateException; d&jjWlHgEN
BwxnDe G)
import org.flyware.util.page.Page; rjUBLY1(
V^n0GJNo
import com.adt.bo.Result; JrDHRIkgm
B3mS]
/** \D?:J3H*]
* @author Joa LkBZlh_
*/ #~k[ 6YR 0
publicinterface UserManager { \iru7'S
/^:2<y8Ha
public Result listUser(Page page)throws Q[PK`*2)
\dcdw*v@
HibernateException; kUa)smh
7Fz
xe$A
} ES}. xZ#~
\}JrFc%O
#Qh>z%Mn^3
b9Y_!Qe
- $JO8'TP
java代码: >w.'KR0L
C>X|VP|C
]^K;goQv
/*Created on 2005-7-15*/ *HE^1IEl
package com.adt.service.impl; L8&D(wh/f
S~)w\(r
import java.util.List; x<ax9{
M2@;RZ(|
import net.sf.hibernate.HibernateException; ?n]FNjd
mS%4gx~~_n
import org.flyware.util.page.Page; lb~E0U`\E`
import org.flyware.util.page.PageUtil; MBw-*K'?zB
CPviR<ms_
import com.adt.bo.Result; NTmi 2c
import com.adt.dao.UserDAO; /L v1$~
import com.adt.exception.ObjectNotFoundException; dMvp&M\\'
import com.adt.service.UserManager; #BY`h~&T
#@qN8J}R
/** 6/tI8H3E
* @author Joa SfB8!V|;
*/ m"d/b~q
publicclass UserManagerImpl implements UserManager { uzBz}<M=
?j{C*|yHO
private UserDAO userDAO; OBOwz4<
T_;]fPajjD
/** DlTR|(AL
* @param userDAO The userDAO to set. w?LrJ37u
*/ |`O7nOM
publicvoid setUserDAO(UserDAO userDAO){ =X(%Svnp
this.userDAO = userDAO; H&4~Uo.5
} Rc[ 0aj:
zY=jXa)K~
/* (non-Javadoc) A\QJLWBv^$
* @see com.adt.service.UserManager#listUser 7:Ztuc]
?=Db@97
(org.flyware.util.page.Page) o3N] `xD'
*/ \we\0@v
public Result listUser(Page page)throws ?&X6:KJQ
0CAa^Q^w
HibernateException, ObjectNotFoundException { qp p/8M
int totalRecords = userDAO.getUserCount(); M \D]ml~
if(totalRecords == 0) bRo|uJ:d
throw new ObjectNotFoundException %Mn.e a
1n=_y o
("userNotExist"); u\1>gDI )|
page = PageUtil.createPage(page, totalRecords); H !)=y
List users = userDAO.getUserByPage(page); x_MJJ(q8g
returnnew Result(page, users);
CN&
} *>q/WLR
sZhMa>
} 'Ot,H_pE
a|_p,_
9YN?
cYNV\b4-
lr@#^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8g~EL{'
q]% T:A=
询,接下来编写UserDAO的代码: T:iP="?{
3. UserDAO 和 UserDAOImpl: _.V?A*
java代码: Sq2P-y!w
?1I GYyu!
3l1cyPv
/*Created on 2005-7-15*/ jO~:<y3
=
package com.adt.dao; 3Q By\1h.
HU ;#XU1
import java.util.List; {~Tg7<\L
,
YW|n:X
import org.flyware.util.page.Page; 4QHS{tj
s!+
pL|
import net.sf.hibernate.HibernateException; ?]O7Ao
kv{}C)kt3
/** Vw{*P2v)
* @author Joa g);^NAA
*/ hJ;$A*Y
publicinterface UserDAO extends BaseDAO { B 0ee?VC
'gMfN
publicList getUserByName(String name)throws ]wVk+%e
YT#3n
HibernateException; ]lO h&Cz[
#*%q'gyHT
publicint getUserCount()throws HibernateException; ,e722wz
NH A 5e<
publicList getUserByPage(Page page)throws m#!=3P7T
YB( Gk;]
HibernateException; Qdk6Qubi!
v`PY>c6~
} H^%lDz
L1{GL #qV
5z}w}zdg
AyKMhac
NAC_pM&B
java代码: fwR_OB:$
7- d.ZG
wK_]/Q-L
/*Created on 2005-7-15*/ (!L5-8O
package com.adt.dao.impl; `)iY}Iu
*/qtzt
import java.util.List; 4,Ic}CvM
\nNXxTxX!
import org.flyware.util.page.Page; =uHnRY
}yn0IWVa
import net.sf.hibernate.HibernateException; kRJ4-n^@><
import net.sf.hibernate.Query; '9p@vi{\
56lCwXCgA
import com.adt.dao.UserDAO; YY((#"o;l
D/y bFk
/** hwYQGtjF
* @author Joa H6*^Ga
*/ H`hnEOyLp
public class UserDAOImpl extends BaseDAOHibernateImpl xM >W2
ZUm?*.g\^
implements UserDAO { \>. LW9
1/+C5Bp*
/* (non-Javadoc) }|OaL*|u
* @see com.adt.dao.UserDAO#getUserByName >SF Uy\3
=ac_,]z
(java.lang.String) 82{ Vc
*/ hXIro
publicList getUserByName(String name)throws c,MOv7{x_
3rW|kkn
HibernateException { 'NjzgZ~]P
String querySentence = "FROM user in class 7,qYV}
:$;Fhf<5
com.adt.po.User WHERE user.name=:name"; a]17qMl
Query query = getSession().createQuery q%n6K
gN8hJG'0
(querySentence); $,=6[T!z+e
query.setParameter("name", name); AN:sQX`
return query.list(); !%+2Yifna
} jd]s<C3o
"xI"
/* (non-Javadoc) 2"P99$"
* @see com.adt.dao.UserDAO#getUserCount() 6k{2 +P
*/ ,_aM`%q?Fj
publicint getUserCount()throws HibernateException { <P[T!gST
int count = 0; bK"SKV
String querySentence = "SELECT count(*) FROM i$G;f^Z!Y
XgN` 7!Z
user in class com.adt.po.User"; h+p*=|j`
Query query = getSession().createQuery u@'0Vk0zGH
>WJf=F`_H
(querySentence); K5ZC:Ks
count = ((Integer)query.iterate().next l:0s2
[v7^i_d
()).intValue(); 5,qj7HZF
return count; _R'Fco
} '|]e<Mt-
Q)m4_+,d
/* (non-Javadoc) ?&G`{Ey
* @see com.adt.dao.UserDAO#getUserByPage E1dD7r\
^'CPM6J
(org.flyware.util.page.Page) n~"$^Vr
*/ <?-YTY|
publicList getUserByPage(Page page)throws w{[=l6L m
4%4avEa"w
HibernateException { (fNUj4[
String querySentence = "FROM user in class 1_fZm+oW!
;{i'#rn{
com.adt.po.User"; 0nn okN^
Query query = getSession().createQuery YBYZ=,"d
K8n4oz#z
(querySentence); >EL)X
#e
query.setFirstResult(page.getBeginIndex()) 'E/*d2CDM(
.setMaxResults(page.getEveryPage()); 0iULCK
return query.list(); H9h@ sSg
} ^4r73ak/):
#_lt~^6
} C{sLz9
S(S#
xq-17HKs
7^wc)E^H
:tIC~GG]_)
至此,一个完整的分页程序完成。前台的只需要调用 IDkWGh
*n]7
userManager.listUser(page)即可得到一个Page对象和结果集对象 \k;`}3uO
~$'\L
的综合体,而传入的参数page对象则可以由前台传入,如果用 Fc~'TBf,,`
`U+l?S^$
webwork,甚至可以直接在配置文件中指定。 [A}rbD K
}kw/W#)J
下面给出一个webwork调用示例: 4h5g'!9-g
java代码: b'VV'+|
5MFxo63
,jXM3?>B
/*Created on 2005-6-17*/ O^/Maa/D1
package com.adt.action.user; FMkOo2{
>fH=DOz$&
import java.util.List; u` oq(?|
Fk(JSiU
import org.apache.commons.logging.Log; j1_@qns{
import org.apache.commons.logging.LogFactory; <;E
import org.flyware.util.page.Page; `_b`kzJ
;Yi4Xva@
import com.adt.bo.Result; )jq?lw'&
import com.adt.service.UserService; V"p!Bf
import com.opensymphony.xwork.Action; 1;Pv0&[q/
QO"oEgB`+Z
/** qB)"qFa
* @author Joa DI!V^M[~u
*/ uB!kM
publicclass ListUser implementsAction{ 2H.654
jp $Z]
privatestaticfinal Log logger = LogFactory.getLog 763+uFx^
GUF"<k
(ListUser.class); K3\#E/Ox
gp$Ucfu'
private UserService userService; 8$(Dz]v|[&
!61Pl/uQ
private Page page; !LkWzn3
nW;g28
privateList users; aM7uBx\8 5
>A0k 8T
/* "NgoaG~!YO
* (non-Javadoc) sXd8rj:o
* rr#K"SP
* @see com.opensymphony.xwork.Action#execute() Vd=yr'?
*/ B||;'
publicString execute()throwsException{ .VTy[|o
Result result = userService.listUser(page); K}6dg<
page = result.getPage(); Cy*|&=>j
users = result.getContent(); l>Ub!^;
return SUCCESS; 0IQ'3_
} {.yStB.T
]xguBh ]
/** E*# ]**
* @return Returns the page. F:6SPY
y
*/ =]-j;#'&
public Page getPage(){ 6a;v&5
return page; nFe%vu8a
} N}\[Gr
q>w)"Dd
/** `vc
"Q/
* @return Returns the users. #2`D`>7456
*/ 1SrJ6W @j[
publicList getUsers(){ 4%1D}9hO6
return users; rQ=,y>-*
} U^qt6$bK
S1/`th
/** " R8KQj
* @param page Hcc"b0>}{
* The page to set. %Th>C2\
*/ @iEA:?9uX
publicvoid setPage(Page page){ 4A9{=~nwT
this.page = page; ?|:BuHkT
} O@?kT;B
zni)<fmju
/** Isx#9C
* @param users 191&_*Xb
* The users to set. PQ@L+],C
*/ ORu2V#Z[
publicvoid setUsers(List users){ -{`@=U
this.users = users; |Yq$sU
} c{[q>@y
pK
A>{p2?`+!
/** Fq9Q+RNMZL
* @param userService zD3mX<sw
* The userService to set. 9<Kj6t_
*/ +:3*
publicvoid setUserService(UserService userService){ gIA@l`"
this.userService = userService; V'w@rc\XN
} w&xDOyW]
} O$IjNx
m^x6>9,
D~o$GW%
N41 R
<L&m4O#|
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, y<b{Ji e
/x{s5P3
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 Py`N4y~
P,sjo u^
么只需要: GWvH[0
java代码: 9}z0J
QM?#{%31
&sF^Fgg{
<?xml version="1.0"?> r!,}Z=cGe
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fvb=#58N_
*Sh^J+j
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
xG;-bJu
OM{WI27
1.0.dtd"> inlk++Og
"(qw-kil
<xwork> fAB e
." $
<package name="user" extends="webwork- jF[ 1za
U\rh[0
interceptors"> y,pZTlE
N?X~ w <
<!-- The default interceptor stack name |pa$*/!NT
uytE^
--> Et_V,s<|
<default-interceptor-ref "[:iXRu
k<+0o))
name="myDefaultWebStack"/> S.!UPkW H
:$+-3_oLMQ
<action name="listUser" @|'5n
wW>)(&!F
class="com.adt.action.user.ListUser"> g:0#u;j^7
<param h_d<!
zXsc1erli
name="page.everyPage">10</param> oq*N_mP0
<result UJs$q\#RO
JMdPwI
name="success">/user/user_list.jsp</result> r <
cVp^
</action> 3Tq\BZ
WMMO5_Mz
</package> Y?534l)j
Mc!Xf[
</xwork> )#F]G$51r
q64k7<C,
16SOIT
upvS|KUil
-R>}u'EG>
X\}Y
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 81*M= ?
~SvC[+t+U
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 5Zw1y@k(
Y
wkyq>Rv
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 p\{-t84n
bqQq=SO
[yj).*0
u{z``]
NzKUtwnIz
我写的一个用于分页的类,用了泛型了,hoho Ej7 /X ~
Blq8H"3!:
java代码: pWu LfX
34!dYr%
RI2f`p8k
package com.intokr.util; 'Peni1_
Nm):9YQ/
import java.util.List; 1N2,mo?2
_Jv
9F8v
/** &Z?ut*%S
* 用于分页的类<br> SE7W F18A
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ASPy
* h d~$WV0#
* @version 0.01 U:F/iXz
* @author cheng 4.RG4Jq
*/ ~XeFOMq
public class Paginator<E> { a}Sd W
privateint count = 0; // 总记录数 PA w-6;
privateint p = 1; // 页编号 _7DkS}NJs
privateint num = 20; // 每页的记录数 CQ;]J=|<_
privateList<E> results = null; // 结果 A8A~!2V
oUQ07z\C
/** 20rkKFk*
* 结果总数 {G*A.$-d
*/ ceGa([#!\_
publicint getCount(){ e4FM} z[
return count; )6~1 ^tD
} d3^OEwe
rw)kAe31
publicvoid setCount(int count){ v+"rZ
this.count = count; '&;yT[
} aQ j*KMc
`MP|Ovns:H
/** fA48(0p
* 本结果所在的页码,从1开始 fri0XxF
* mW%?>Z1=>d
* @return Returns the pageNo.
kj5Q\vr)
*/ BK,sc'b
publicint getP(){ l<(Y_PE:
return p; ~7!7\i,Y8\
} v&FF|)$
w#i[_
/** 97!>%d[0
* if(p<=0) p=1 z'p:gv]
* Da$r `
* @param p g/UaYCjM
*/ Y,8KPg@W
publicvoid setP(int p){ P\CDd=yWc
if(p <= 0) 0tk#Gs[
p = 1; VCy5JH
this.p = p; I &* _,d
} YJxw 'U
>P
Ff^@~X+W<
/** V E2tq k%
* 每页记录数量 ;DnUQj
*/ G= ^X1+_
publicint getNum(){ ,a?\MM9$
return num; 1p`+
} /9yaW7w
S'~o,`xy
/** <*H^(0
* if(num<1) num=1 uR6w|e`
*/ z<gu00U7
publicvoid setNum(int num){ t)oa pIeIe
if(num < 1) "x'),
num = 1; h?\2_s
this.num = num; S~$'WA
} ea=83 Zj
Wi n8LOC
/** 0%s|Zbo!>
* 获得总页数 nRhrWS
*/ {+zJI-XN/
publicint getPageNum(){ *5$&`&,
return(count - 1) / num + 1; AgF5-tz6x
} +)nT|w45
iV.p5FD
/** ~`Qko-a&
* 获得本页的开始编号,为 (p-1)*num+1 M^rM-{?<
*/
>95TvJ
publicint getStart(){ Hg}I]!B
return(p - 1) * num + 1; {mE! Vf
} p<WFqLe(":
7=4 A;Ybq
/** VVWM9x
* @return Returns the results. RaSz>-3d
*/ e2$]g>
publicList<E> getResults(){ .V6-(d
return results; E&
36H
} A CNfS9M_w
2=PBxDs;
public void setResults(List<E> results){ ghk5rl$
this.results = results; NCA{H^CL
} @D`zKYwX1
i`%.
public String toString(){ ;)DzCc/
StringBuilder buff = new StringBuilder z}}]jR\y?
V9x8R
(); e1
*__'
buff.append("{"); ,$r2gr!_G
buff.append("count:").append(count); X_; *`,<T
buff.append(",p:").append(p); fm1X1T .
buff.append(",nump:").append(num); dw@E)
buff.append(",results:").append ]8 U ~Iy
]0c Pml
(results); IKvBf'%-
buff.append("}"); ^c9ThV.v
return buff.toString(); `NwdbKX
} juToO
w5]"ga>Y
} QF-)^`N
w'Z!;4E0
7x.%hRk