Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 H-U_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Q2uV/M1?
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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 f'H|K+bO
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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 nSC2wTH!1
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。 `fTM/"
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分页支持类: c38XM]Jeq
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java代码: =I)43ahd
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package com.javaeye.common.util; 46Sz#^y
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import java.util.List; ,3y9yJQa*#
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publicclass PaginationSupport { e)g&q'O
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publicfinalstaticint PAGESIZE = 30; %kjG[C
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privateint pageSize = PAGESIZE; ;ryNfP%
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privateList items; ng"=vmu
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privateint totalCount; q`b6if"
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privateint[] indexes = newint[0]; I/MY4?(T
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privateint startIndex = 0; c{BAQZVc
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public PaginationSupport(List items, int AcPLJ!y
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totalCount){ ^Laqq%PI
setPageSize(PAGESIZE); t'2A)S
setTotalCount(totalCount); ~v8X>XDL?T
setItems(items); !=YE hQ-
setStartIndex(0); }#7l-@{<
} dfFw6R
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public PaginationSupport(List items, int ZLzc\>QX
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totalCount, int startIndex){ bUcp8
setPageSize(PAGESIZE); $W7}Igx#
setTotalCount(totalCount); V0^{Ss1M
setItems(items); Pg}QRCB@
setStartIndex(startIndex); ec;
} Phi5;U!
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public PaginationSupport(List items, int P^OmJ;""D
*)RKU),3nL
totalCount, int pageSize, int startIndex){ 6,5h4[eF*
setPageSize(pageSize); ]$ d ;P
setTotalCount(totalCount); Q\4tzb]
setItems(items); pFH.beY
setStartIndex(startIndex); 93*d:W8Vr
} X$UK;O
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publicList getItems(){ dU9;sx
return items; z I2DQ]
9
} 2-@)'6"n
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publicvoid setItems(List items){ t{c:<nN
this.items = items; sUlf4<_zW
} (m'-1wX.
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publicint getPageSize(){ H5 z1_O_+
return pageSize; r[(;J0=
} 6?u`u t
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publicvoid setPageSize(int pageSize){ }<~(9_+
this.pageSize = pageSize; <%YW/k"o
} HN7tIz@Frc
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publicint getTotalCount(){ m}z6Bbis 0
return totalCount; -F?97&G$
} q;[HUyY,
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publicvoid setTotalCount(int totalCount){ CF>&mXg\
if(totalCount > 0){ *sldv
this.totalCount = totalCount; ,Vq$>T@z
int count = totalCount / vu)EB!%[
oz=V|7,
pageSize; c@g(_%_|2
if(totalCount % pageSize > 0) =RHtugwy
count++; !:xycLdfUp
indexes = newint[count]; <n,QSy#
for(int i = 0; i < count; i++){ c1E{J<pZ
indexes = pageSize * Yeg<MrS4D
J.R])
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} B>1,I'/$.
}else{ ~qZ6I)?
this.totalCount = 0; $e+4Kt
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} uD(C jHM>
} .nZKy't
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publicint[] getIndexes(){ yf&_l^!
return indexes; f?:=@35
} /ckkqk"
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publicvoid setIndexes(int[] indexes){ >TglX t+
this.indexes = indexes; Fm:Ys](
} @U!&XZ]h
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publicint getStartIndex(){ LCSvw
return startIndex; G%k&|
} :xHKbWz6j
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publicvoid setStartIndex(int startIndex){ `^#4okg]
if(totalCount <= 0) E{[Y8U1n
this.startIndex = 0; l 7uTk5
elseif(startIndex >= totalCount)
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this.startIndex = indexes r-YJ$/J
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[indexes.length - 1]; ~~|Iw=:
elseif(startIndex < 0) +%j27~R>D
this.startIndex = 0; L{VnsY V
else{ L+G0/G}O\
this.startIndex = indexes mxZ+r#|di
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[startIndex / pageSize]; :[+8(~| za
} [>mH
} D}
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publicint getNextIndex(){ |=ph&9
int nextIndex = getStartIndex() + @p~scE.#\
x %`YV):*
pageSize; Wu*
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if(nextIndex >= totalCount) va_u4
return getStartIndex(); /ojx$Um
else qCI7)L`
return nextIndex; \]4EAKJE
} qpFxl
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publicint getPreviousIndex(){ ,mx\
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int previousIndex = getStartIndex() - VoYL}67c
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pageSize; @;Jv/N6@
if(previousIndex < 0) WZ>nA [/
return0; FRR05%K
else u=Ik&^v
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return previousIndex; ,\iXZ5"R
} 59{X;
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} 7w2$?k',-
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抽象业务类 mWYrUI
java代码: ]QHp?Ii1
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/** 5-GS@fY
* Created on 2005-7-12 "`cN k26JZ
*/ f8[O]MrO;
package com.javaeye.common.business; ;G}
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import java.io.Serializable; {H(l"KuL
import java.util.List; _ f";zd
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import org.hibernate.Criteria; 9tv,,I;iU
import org.hibernate.HibernateException; , @UOj=
import org.hibernate.Session; BFw_T3}zn
import org.hibernate.criterion.DetachedCriteria; {e|.AD
import org.hibernate.criterion.Projections; %w[Z/
import 8#JX#<HEo
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org.springframework.orm.hibernate3.HibernateCallback; <A=1]'1\r
import &*"*b\
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org.springframework.orm.hibernate3.support.HibernateDaoS \~A qA!)6
^CLQs;zXE
upport; s!?uLSEdb
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends .B<Bqr@?8
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HibernateDaoSupport { .Ja].hP
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privateboolean cacheQueries = false; tnnGM,"ol
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privateString queryCacheRegion; SWx: -<
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publicvoid setCacheQueries(boolean v.<mrI#?
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cacheQueries){ JqMF9|{H
this.cacheQueries = cacheQueries; }NyQ<,+mq&
} u$^tRz9
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publicvoid setQueryCacheRegion(String V6P-?Nd
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queryCacheRegion){ 04dz?`HuB
this.queryCacheRegion = p,8~)ic_
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queryCacheRegion; +Mijio
} ou-UR5
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publicvoid save(finalObject entity){ 2rT^OGw6
getHibernateTemplate().save(entity); wjl )yo$z
} \AroSy9
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publicvoid persist(finalObject entity){ :Q"|%#P
getHibernateTemplate().save(entity); Sp X;nH-D
} aA#79LS
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publicvoid update(finalObject entity){ 1b1Ab
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getHibernateTemplate().update(entity); Q
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} Dj96t5R
) %Fwfb
publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); ?< b{
} J?3/L&seA
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publicObject load(finalClass entity, GqR XNs!
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finalSerializable id){ I)'bf/6?
return getHibernateTemplate().load ujxr/8mjV
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(entity, id); Cty#|6k
} ` 'Qb?F6
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publicObject get(finalClass entity, =D$ED^W
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finalSerializable id){ 5_'lu
return getHibernateTemplate().get &;-zy%#l
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(entity, id); <v0`r2^S{-
} RX>P-vp
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publicList findAll(finalClass entity){ #gV n7wq
return getHibernateTemplate().find("from I2*rtVAP'j
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" + entity.getName()); q_.fVn:!
} d:';s~
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publicList findByNamedQuery(finalString RJ3oI+gI
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namedQuery){ WChP,hw
return getHibernateTemplate hNN[dj R
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().findByNamedQuery(namedQuery); p@G7}'|eyA
} nU_O|l9
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publicList findByNamedQuery(finalString query, pjFO0h_Y
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finalObject parameter){ ;_(f(8BO
return getHibernateTemplate +>q#eUS)
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().findByNamedQuery(query, parameter); JaY"Wfc
} geR+v+B,
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publicList findByNamedQuery(finalString query, hU#e\L 7
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finalObject[] parameters){ ]j*2PSJG
return getHibernateTemplate } jj)
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().findByNamedQuery(query, parameters); w2nReB z
} \2s`mCY
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publicList find(finalString query){ "OjAhKfG
return getHibernateTemplate().find Eu?z!
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(query); lDYgtUKG
} [7v|bd
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publicList find(finalString query, finalObject !y_{mE?V(
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parameter){ Q6Gw!!Z5EA
return getHibernateTemplate().find zi-_ l
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(query, parameter); G|g^yaq>
} nQc#AFg
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public PaginationSupport findPageByCriteria O]u'7nO{{
"Q.*
(final DetachedCriteria detachedCriteria){ R_PF*q2 '
return findPageByCriteria 5Kg'&B (
aZA``#p+
(detachedCriteria, PaginationSupport.PAGESIZE, 0); vamZKm~p
} jfuHZ^ YA
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public PaginationSupport findPageByCriteria AYbO~_a\N
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(final DetachedCriteria detachedCriteria, finalint +Y%6y]8
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startIndex){ [r/zBF-.
return findPageByCriteria &P?2H66s
j<<d A[X
(detachedCriteria, PaginationSupport.PAGESIZE, FO2e7p^Q
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startIndex); Op'a=4x]
} H-kX-7C
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public PaginationSupport findPageByCriteria UPh#YV 0/,
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(final DetachedCriteria detachedCriteria, finalint ,'X"(tpu@
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pageSize, VPUVPq~&
finalint startIndex){ "}]$ag!`q$
return(PaginationSupport) &~,4$&_
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getHibernateTemplate().execute(new HibernateCallback(){ /v R>.'
publicObject doInHibernate ZL!u$)(V
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(Session session)throws HibernateException { t2N W$
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Criteria criteria = &3Zq1o
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detachedCriteria.getExecutableCriteria(session); 9@
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int totalCount = V%s
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((Integer) criteria.setProjection(Projections.rowCount Kw
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()).uniqueResult()).intValue(); @5%&wC
criteria.setProjection "7B}hZ^)W
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(null); @UD:zUT)F
List items = ~r --dU
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criteria.setFirstResult(startIndex).setMaxResults UnhVppnex
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(pageSize).list(); GShxPH{_j
PaginationSupport ps = -JMn?]
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new PaginationSupport(items, totalCount, pageSize, ^xZh@e5
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startIndex);
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return ps; [xMa^A>p
} g*Y,.
}, true); y?$DDD
} '0+*
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public List findAllByCriteria(final $83B10OQ&L
'/W$9jm
DetachedCriteria detachedCriteria){ <L&EH@T
return(List) getHibernateTemplate g52a
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().execute(new HibernateCallback(){ I.<c{4K5
publicObject doInHibernate 2{OR#v~
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(Session session)throws HibernateException { /).{h'^Hq\
Criteria criteria = R?{+&r.X
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detachedCriteria.getExecutableCriteria(session); Wlj&_~
return criteria.list(); .JhQxXj
} *3GV9'-P
}, true); 4U}qrN~=
} "/W[gP[y%
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public int getCountByCriteria(final )g0fN+Mb
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DetachedCriteria detachedCriteria){ M;(,0d k
Integer count = (Integer) UiFH*HT
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getHibernateTemplate().execute(new HibernateCallback(){ )pnyVTKt
publicObject doInHibernate +&EXTZ@o
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(Session session)throws HibernateException { gAqK)@8-
Criteria criteria = ?e7]U*jEU
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detachedCriteria.getExecutableCriteria(session); o5 L ^
return F@w; .e!
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criteria.setProjection(Projections.rowCount IrLGAQ0
qL(Q1O!
()).uniqueResult(); }r:o8+4
} T<AT&4
}, true); 4fEDg{T
return count.intValue(); }cKB)N
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} S{@}ECla
} zw0w."V
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用户在web层构造查询条件detachedCriteria,和可选的 ~wc:/UM|
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 qQ&uU7,#
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PaginationSupport的实例ps。 wp[Ug2;G
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ps.getItems()得到已分页好的结果集 bOS)vt*V
ps.getIndexes()得到分页索引的数组 MK$u}G
ps.getTotalCount()得到总结果数 'M90Yia
ps.getStartIndex()当前分页索引 ?$ r`T]>`2
ps.getNextIndex()下一页索引 0XHQ5+"8
ps.getPreviousIndex()上一页索引 M6Fo.eeK3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _T=g?0
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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 $o^Z$VmL
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一下代码重构了。 NW3c_]`=
4zug9kFK
我把原本我的做法也提供出来供大家讨论吧: hlTbCl
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首先,为了实现分页查询,我封装了一个Page类: Hvl
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java代码: taQE
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/*Created on 2005-4-14*/ >t D=t8
package org.flyware.util.page; aQkOQy
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/** 3r\8v`^>
* @author Joa d|`Ll
* 4ls:BO;k]
*/ *6uccx7{
publicclass Page { ?GhyVXS y.
8~sP{V%
/** imply if the page has previous page */ )8Va%{j
privateboolean hasPrePage; 9
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}x8!{Y#cF
/** imply if the page has next page */ 1+o]+Jz|
privateboolean hasNextPage; f0<zK!
md!6@)S-p
/** the number of every page */ 1GY2aZ@
privateint everyPage; %|Ps|iV
jYsAL=oh,*
/** the total page number */ c/{FDN
privateint totalPage; >.h:Y5
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/** the number of current page */ Rx%S<i;9
privateint currentPage; ^5mc$~1`
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/** the begin index of the records by the current *bkb-nKw
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query */ +)]YvZ6%[,
privateint beginIndex; UZZJtQt
9KSi-2?H
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/** The default constructor */ rg/{5f
public Page(){ DwD$T%kF
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} 74s{b]jN'-
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/** construct the page by everyPage 1uF$$E6[
* @param everyPage QYJ
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* */ cHFi(K]|1
public Page(int everyPage){ 0X$mT:=9
this.everyPage = everyPage; 99m2aT()
} 8hRcB[F~S
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/** The whole constructor */ gN&i&%*!
public Page(boolean hasPrePage, boolean hasNextPage, pO]gf$
zF&VzNR2
T U%@_vYR
int everyPage, int totalPage, OvdT* g=8*
int currentPage, int beginIndex){ %pWn9
this.hasPrePage = hasPrePage; Bx\&7|,x
this.hasNextPage = hasNextPage; sFU< PgV
this.everyPage = everyPage; V35Vi6*p
this.totalPage = totalPage; |dRVSVN
this.currentPage = currentPage; 3"fDFR
this.beginIndex = beginIndex; A_9WSXR
} $JE,u'JQ
!(sn9z#
/** e3~MU6
* @return i1iP'`r
* Returns the beginIndex. K g@'mG
*/ f%Q)_F[0D4
publicint getBeginIndex(){ +`y(S}Z
return beginIndex; _=v#"l
} +z
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/** N(/) e
* @param beginIndex gesbt
* The beginIndex to set. >A#5` $i
*/ &$"#hGg
publicvoid setBeginIndex(int beginIndex){ Lp`.fn8Ln
this.beginIndex = beginIndex; x`CjFaE~F
} #A63?kDE&&
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/** _0H oJ
* @return UBvp32p
* Returns the currentPage. i,Ct AbMx
*/ uo F.f$%"
publicint getCurrentPage(){ ^$c#L1
C
return currentPage; m_NX[>&Y3
} `FHudSK
F^ q{[Z
/** 4vhf!!1
* @param currentPage MlO OB
* The currentPage to set. -Cf)`/
*/ }$6L]
publicvoid setCurrentPage(int currentPage){ oOFTQB_6
this.currentPage = currentPage; ~uQ*u.wi
} )'shpRB;1
Spm 0`
/** 6F\ 6,E
* @return }~FX!F#oU
* Returns the everyPage. WP<L9A
*/ Xr*I`BJ
publicint getEveryPage(){ 1v@#b@NXM7
return everyPage; W/'1ftn?D
} 0cG'37[
bWPsfUn#
/** z4u.bU
* @param everyPage )>a~ %~:
* The everyPage to set. RQ+, 7Ir
*/ !V|{(>+<
publicvoid setEveryPage(int everyPage){ (m]l -Re
this.everyPage = everyPage; 8P I%Z6
} d)%WaM%V
SX4*804a_
/** '|}A/`
* @return *A-_*A
* Returns the hasNextPage. U%3N=M
*/ 6v%yU3l
publicboolean getHasNextPage(){ ^F^g(|(K
return hasNextPage; |r9<aVlK
} LI,wSTVjC
~Xi@#s~
/** oEIpv;:_
* @param hasNextPage Rv1W &s&
* The hasNextPage to set.
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*/
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publicvoid setHasNextPage(boolean hasNextPage){ $4bc!
this.hasNextPage = hasNextPage; Hv6h7-
} )f?I{
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/** r$jWjb
* @return O&!R7T
* Returns the hasPrePage. &raqrY|V
*/ 3%vXB=>T!
publicboolean getHasPrePage(){ T(|'.&a
return hasPrePage; I~,.@{4
} wMS%/l0p1
]n^iG7aB?
/** xoZm,Pxd
* @param hasPrePage ~nZcA^b#DQ
* The hasPrePage to set. k4+vI1Cs
*/ *s6x
publicvoid setHasPrePage(boolean hasPrePage){ zs$r>rlO
this.hasPrePage = hasPrePage; $6"sR I6u
} 9A|A@E#
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/** 7x)Pt@c
* @return Returns the totalPage. jAJ='|[X\
*
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*/ 3Z*r#d$nh:
publicint getTotalPage(){ fA=Z):w
return totalPage; 9QQ XB-
} Xv1vq
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.Fb#j+Lq
/** ~yv7[`+Tgg
* @param totalPage b]u$!W
* The totalPage to set. Ft5A(P >
*/ *%xbn8
publicvoid setTotalPage(int totalPage){ Y ^^4n$
this.totalPage = totalPage; 4m*)("H
} XkI'm\W
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} yan^\)HZ
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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 1>(EvY}Y\
R"ON5,E
个PageUtil,负责对Page对象进行构造: G,C`+1$*
java代码: *6I$N>1
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/*Created on 2005-4-14*/ MQ,K%_m8
package org.flyware.util.page; IQ&PPC
WNR]GI
import org.apache.commons.logging.Log; vF\>;pcT
import org.apache.commons.logging.LogFactory; O_QDjxj^rZ
,gV#x7IW
/** *aErwGLB8
* @author Joa .W]k8N E
* l!ow\ZuQBF
*/ ]V"P
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publicclass PageUtil { l7`{ O/hN
K0w}l" )A
privatestaticfinal Log logger = LogFactory.getLog =O}I{dNKZV
^0]0ss;##R
(PageUtil.class); `gSMb
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}rQ Qe:{]B
/** 8D.c."q
* Use the origin page to create a new page ]B>76?2W
* @param page !MoAga_
j
* @param totalRecords t6Iy5)=zY
* @return BU -;P
*/ bEcs(Mc~
publicstatic Page createPage(Page page, int gIo\^ktW
aM5]cc%
totalRecords){ ?/|Xie
return createPage(page.getEveryPage(), E/cV59
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page.getCurrentPage(), totalRecords); h,/Aq
} ?:r?K|Ku
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/** IfmQPs+f
* the basic page utils not including exception [,Ehu<mEK
L<FXtBJ
handler E{
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b)
* @param everyPage /LFuf`bXV
* @param currentPage vyZ&%?{*R
* @param totalRecords dN5{W0_
* @return page 8N&'n
*/ oAO{4xP
publicstatic Page createPage(int everyPage, int (d4btcg
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currentPage, int totalRecords){ tz;3
everyPage = getEveryPage(everyPage); cWW?@_
currentPage = getCurrentPage(currentPage); 8 a]'G)(ts
int beginIndex = getBeginIndex(everyPage, ]bds~OY5 U
l"ms:v
currentPage); B[8bkFS>]
int totalPage = getTotalPage(everyPage, s{b\\$Rb
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totalRecords); O9daeIF0#
boolean hasNextPage = hasNextPage(currentPage, GDSV:]hL
}=X: F1S
totalPage); o`f^ m
boolean hasPrePage = hasPrePage(currentPage); ZLjAhd)
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returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, hs7!S+[.$$
currentPage, <AU*lLZ
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beginIndex); .B]l@E-u
} "t^v;?4
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privatestaticint getEveryPage(int everyPage){ gqS9 {K(f
return everyPage == 0 ? 10 : everyPage; 0+SDFh
} tWn
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a&>NuMDI
privatestaticint getCurrentPage(int currentPage){ QIiy\E%
return currentPage == 0 ? 1 : currentPage; tp`1S+'~j
} MtkU]XKGT
%`F;i)Zz
privatestaticint getBeginIndex(int everyPage, int 6f +aGz
f<8Hvumw
currentPage){ lpG%rN!
return(currentPage - 1) * everyPage; ^/BGOBK
} ",,# q
Mj;V.Y
privatestaticint getTotalPage(int everyPage, int H,} &=SCk
W6<oy
totalRecords){ %,bD|
NKp
int totalPage = 0; -rO34l
Db"mq'vT
if(totalRecords % everyPage == 0) %:aXEjm@
totalPage = totalRecords / everyPage; l5-[a
else Oc L7] b0
totalPage = totalRecords / everyPage + 1 ; mG
S4W;
krfXvQJwJ
return totalPage; o-6d$c}{f
} BpIyw
9rEBq&
privatestaticboolean hasPrePage(int currentPage){ 6U{A6hH]
return currentPage == 1 ? false : true; T#B#q1/
} >[ B.y
u ON(LavB
privatestaticboolean hasNextPage(int currentPage, r,;ca6>5H
wsmgkg
int totalPage){ HAn{^8"@
return currentPage == totalPage || totalPage == -+"#G?g
B[L m}B[
0 ? false : true; ]LB_ @#
} Z8E<^<|
~kZdep^]
F
CYGXtc
} M5no4P<
-+ByK#<%
-$8ew+
vh\i ^
Ic(qA{SM
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 `O6#-<>
F;Q,cg M
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 L"ho|v9:
2Wzx1_D"a
做法如下: >W> rhxU
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?L }>9$"
ZN8j})lE
的信息,和一个结果集List: D_lRYLA+
java代码: SWrTM
,1ev2T
jt}Re,
/*Created on 2005-6-13*/ 8xB-cE
package com.adt.bo; dWn6-es
kgo#JY-4
import java.util.List; _UVpQ5pN
&>qUT]w
import org.flyware.util.page.Page; u
8o!
2}&ERW
/** W^iK9|[qp
* @author Joa d7^
`
*/ Pk;w.)kT
publicclass Result { c+l1l0BA
]+:yfDtZd
private Page page; {\5(aQ)Vi5
1"y!wsM%
private List content; w Q[|D2;
65aYH4"
/** ?J2{6,}O*.
* The default constructor wm@j(h4
*/ P|Aac,nE+^
public Result(){ 2E40&
super(); Yh95W
} =>'8<"M5z
2mEqfy
/** NAo.79
* The constructor using fields z#+WK|a
* br=e+]C Y)
* @param page Kyh6QA^
* @param content >Cr"q*
*/ P8c_GEna
public Result(Page page, List content){ @_`r*Tb)dM
this.page = page; l-w4E"n3
this.content = content; ~ n<|f
} L<V20d9
3.YH7rN
/** L9/'zhiZBx
* @return Returns the content. :kHk'.V1(
*/ w}1IP-
publicList getContent(){ `&NFl'l1C
return content; 9SeGkwec?$
} lB27Z}
F,_cci`p
/** (m1m}* @
* @return Returns the page. /eHf8l
*/ vE9"1M
public Page getPage(){ r^"o!,H9q
return page; HVvm3qu4
} .g/!u(iy
\zJ^XpC
/** r5&c!b \
* @param content W4 q9pHQ
* The content to set. ]/!*^;cY(
*/ f #h0O3
public void setContent(List content){ @16y%]Q-E#
this.content = content; 0iSNom}m
} 26~rEOgJ
{Q/@ Y.~<
/** qF3S\
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* @param page nxN("$'cq
* The page to set. 7h9oY<W
*/ =O8 YU)#
publicvoid setPage(Page page){ "^t7]=q
this.page = page; ~oOv/1v},
} rKPsv*w
} JK)|a@BtOT
'_g&!zi8~
E2
'Al6^C
6Hc25NuQZ
fx 0 8>r
2. 编写业务逻辑接口,并实现它(UserManager, R GV{KL
.~'q
yD2V
UserManagerImpl) iP7KM*ks
java代码: Iy5W/QK6
h<m>S,@g
Ct/6<
/*Created on 2005-7-15*/ MS SHMR
package com.adt.service; w;VUP@Wm
lItr*,A]
import net.sf.hibernate.HibernateException; 0T3r#zQ
>y+j!)\
import org.flyware.util.page.Page; z"5e3w
L%9yFg%u
import com.adt.bo.Result; @TKQ_7BcB
UL7%6v{'*
/** ^<yM0'0t
* @author Joa ~$a%& ]\
*/ UIQ=b;J9
publicinterface UserManager { tORDtMM9+
}xrrHp
public Result listUser(Page page)throws QL(}k)dB
/?j^Qu
HibernateException; `Geq,
]:^kw$
} )fZ5.W8UE]
`.6Jgfu
=7P; /EV
OQX ek@~2
L3Q1az!Ct
java代码: r52,f%nlm
YpZ9h@,
#iGz&S3iN$
/*Created on 2005-7-15*/ tX*L_
package com.adt.service.impl; ,v1-y
?kB
d>4e9M"
import java.util.List; fs]Zw mA^
TAYt:
import net.sf.hibernate.HibernateException; e$(i!G)
>-y&k^a=
import org.flyware.util.page.Page; [76m gj!K
import org.flyware.util.page.PageUtil; ")M.p_b[Z=
/C8(cVNZ
import com.adt.bo.Result; "/XS3sv"s
import com.adt.dao.UserDAO; ~KfjT
p#
import com.adt.exception.ObjectNotFoundException; lR^dT4
import com.adt.service.UserManager; v:T` D
&akMj@4;R
/** NtOR/*
* @author Joa qaGIU`}:$A
*/ :U[_V4?7
publicclass UserManagerImpl implements UserManager { $v oyXi`*
IA!ixabG
private UserDAO userDAO; @%cJjZ5y
mg,f> (
/** FZ2-e
* @param userDAO The userDAO to set. ]R>k0X.V
*/ IKr7"`
publicvoid setUserDAO(UserDAO userDAO){ d<b,LD^
this.userDAO = userDAO; w./EJkKI
} 1k%ko?
o%9>elOju
/* (non-Javadoc) h'fD3Gr&
* @see com.adt.service.UserManager#listUser mVL,J=2
tB3CX\e
(org.flyware.util.page.Page) =K>Z{%i
*/ f8^58]wx0
public Result listUser(Page page)throws DVcu*UVw
#f~a\}$I
HibernateException, ObjectNotFoundException { R39R$\
int totalRecords = userDAO.getUserCount(); ipp_?5TL
if(totalRecords == 0) HgBg,1
throw new ObjectNotFoundException C;)
xjZiR
2M#CJ&
("userNotExist"); rlIEch^wZ
page = PageUtil.createPage(page, totalRecords);
n1/lE)
List users = userDAO.getUserByPage(page); #rr-4$w+
returnnew Result(page, users); =GVhAzD3
} rWs5s!l,
6qJB"_.
} D)sEAfvX
~&/Gx_KU
*vO'Z &
X[~CLKH(
!m|%4/
M@
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 L-R}O
8
{|E7N"Qzg
询,接下来编写UserDAO的代码: m8PB2h
3. UserDAO 和 UserDAOImpl: w1_Ux<RF
java代码: nu<!/O
Mv=cLG?X
Wd5t,8*8
/*Created on 2005-7-15*/ k-e@G'
package com.adt.dao; 4"{wga~%/
i?/?{p$#a-
import java.util.List; /6c10}f
sD3|Qj;
import org.flyware.util.page.Page; /,UkT*+>!
y21uvp'
import net.sf.hibernate.HibernateException; <Y2!c,"
,GnU]f
/** 3pW
MS&
* @author Joa sK?-@
*/ [ d7]&i}*|
publicinterface UserDAO extends BaseDAO { 2oG|l!C
OF/)-}!
publicList getUserByName(String name)throws p ri{vveN@
ZG<!^tj
HibernateException; yo,!u\^x
-(}1o9e\7
publicint getUserCount()throws HibernateException; 30E v"
]?`p_G3O
publicList getUserByPage(Page page)throws j]"xck
]Hy PJ
HibernateException; ug"<\"
p\;)^O4
} H`lD@q'S
E_1I|$
+|YZEC
=>\-ma+
A i){,nh`0
java代码: yKEFne8^
ca*[n~np
zn1Rou]6
/*Created on 2005-7-15*/ O:tX0<6
package com.adt.dao.impl; T}Vpy`
t`ceVS
import java.util.List; xcvr D
_I-VWDCk
import org.flyware.util.page.Page; 6oh@$.ThG
lN>C#e<]
import net.sf.hibernate.HibernateException; SuH.lCF-g
import net.sf.hibernate.Query; tlLn
QsJW"4d
import com.adt.dao.UserDAO; .`>l.gmi&
g+ 1=5g
/** tK}p05nPhl
* @author Joa (2bZ]
*/ |EV\a[
public class UserDAOImpl extends BaseDAOHibernateImpl i(yAmo9h
,,gLrVk
implements UserDAO { _c
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L@n6N|[_
/* (non-Javadoc) 795Jwv
* @see com.adt.dao.UserDAO#getUserByName -jtC>_/
{_XrZ(y/
(java.lang.String) ;s\;78`0
*/ Qj<{oZp&
publicList getUserByName(String name)throws UcLNMn|
]ZKt1@4AY
HibernateException { LX\*4[0%K
String querySentence = "FROM user in class p=_XMh`;
r ctSS:1
com.adt.po.User WHERE user.name=:name"; 0YpiHoM
Query query = getSession().createQuery fQW_YQsb
GtM(
Y
(querySentence); o d}EM_
query.setParameter("name", name); |v$%V#Bo
return query.list(); En,)}yI
} C?60`^
wHOlj)CZ
/* (non-Javadoc) UGmuX:@y76
* @see com.adt.dao.UserDAO#getUserCount() tSb?]J
*/ 9jMC|oE
publicint getUserCount()throws HibernateException { !
nCjA\$
int count = 0; ,zN3? /7
String querySentence = "SELECT count(*) FROM X$- boe?
S?Bc~y
user in class com.adt.po.User"; HCJ8@nki
Query query = getSession().createQuery S~k 0@
e|b~[|;*=
(querySentence); uS,p|}Q&
count = ((Integer)query.iterate().next N4a`8dS|
3'[Rvy{
()).intValue(); 8
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return count; h"u<E\g
} c{mKra
&\1'1`N1
/* (non-Javadoc) S9HBr
* @see com.adt.dao.UserDAO#getUserByPage ShWHHU(QQ
|oe!P}u
(org.flyware.util.page.Page) <H5n>3#pH
*/ G Sz @rDGY
publicList getUserByPage(Page page)throws U#;51_
NZo<IKD$
HibernateException { L289'Gzg
String querySentence = "FROM user in class ,8c
dXt
xdd:yrC
com.adt.po.User"; b:P\=k]8#
Query query = getSession().createQuery 5-8]N>/b!
[8F
\;
(querySentence); [1z{T(dh
query.setFirstResult(page.getBeginIndex()) SkiJpMN
.setMaxResults(page.getEveryPage()); ug^om{e-
return query.list(); Md8(`@`o
} Mn]}s:v
t|;%DA)fjw
} |}_gA
5ZnSA9?
sS,
zzx<
<1aa~duT
.Qd}.EG
至此,一个完整的分页程序完成。前台的只需要调用 89zuL18V
zzX<?6MS
userManager.listUser(page)即可得到一个Page对象和结果集对象 fd4;mc1T
QTVa
的综合体,而传入的参数page对象则可以由前台传入,如果用 It%T7
X#
B-!guf
rnY
webwork,甚至可以直接在配置文件中指定。 B ,V(LTE
&oA~
Tx
下面给出一个webwork调用示例: ~6p5H}'H1
java代码: Q"A_bdg5
6hZ.{8e0
X*0k>j
/*Created on 2005-6-17*/ _zdNLwE[
package com.adt.action.user; mv{<'
g{e/X~
import java.util.List; PmHd9^C
W+KF2(lB
import org.apache.commons.logging.Log; $nj\\,(g
import org.apache.commons.logging.LogFactory; 5i6VZv
import org.flyware.util.page.Page; JlUb0{8PE
)&>L !,z
import com.adt.bo.Result; @9aGz6k+
import com.adt.service.UserService; ?fV?|ZGZI
import com.opensymphony.xwork.Action; jDkm:X}:
22z1g(;@
/** kL|\wci
* @author Joa f_rp<R>Uu
*/ Y,'%7u
publicclass ListUser implementsAction{ fTcY"A,2
0 <g{ V
privatestaticfinal Log logger = LogFactory.getLog }B`Ku5 M
+s ULo
(ListUser.class); sds}bo
opXDm\
private UserService userService; \0nlPXk?G
SyAo,
)j
private Page page; 9:Si]
Pp+S
B[CA
5Ry
privateList users; G{+2xN
a(
pl|h>4af
/* aZ6'|S;
* (non-Javadoc) cAb>2]M5V
* Jld\8=
* @see com.opensymphony.xwork.Action#execute() *jE;9^
*/ uaaf9SL?
publicString execute()throwsException{ myIe_k,F
Result result = userService.listUser(page); J'e]x[Y
page = result.getPage(); Vc _:*
users = result.getContent(); s9i|mVtm8
return SUCCESS; 0elxA8Z~e
} w^Ag]HZN
O[FZq47
/** i $C-)d]
* @return Returns the page. Rk A8
*/ /OG zt
public Page getPage(){ [pL*@9Sa&
return page; /P:EWUf'
} FY4 T(4#
35_)3R)
/** &I/qG`W
* @return Returns the users. Xb,T{.3@
*/ I ]9C_
publicList getUsers(){ u okc:D
return users; to>
} VD[pZ2;4
Qnt5HSSt
/** Oaa"T8t
* @param page w7
*V^B
* The page to set. ~=cmM
*/ hqDqt"dKz
publicvoid setPage(Page page){ n_23EcSy
this.page = page; x+7*ADKb
} -[heV| $;
nB] Ia?
/** Ej"u1F14J
* @param users D(\$i.,b2
* The users to set. WU)Ss`s \
*/ o35fifM`
publicvoid setUsers(List users){ JvL{| KtyU
this.users = users; pj8azFZ
} Ll}yJ#3,
+}JM&bfK
/** ,Eu?JH&}u
* @param userService Gu;OVLR|
* The userService to set. s&Yi 6:J
*/ *C2R`gpBI
publicvoid setUserService(UserService userService){ fk{0d
this.userService = userService; 27#5y_
`
} #*^+F?o,(
} <Ef[c@3
[Qj;/
"rNL
`P7
NX,-;v
Vw~\H Gs/~
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, wT_h!W
>*1}1~uU`'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 @S3f:s0~D
[TTSA2
么只需要: Nneo{j
java代码: D1T@R)j
r>t1 _b+nu
VaLs`q&3>
<?xml version="1.0"?> .*5 Z"Q['G
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Es4qPB`g.
HdX2YPYn;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- K$[$4 dX]
K=\O5#F?3
1.0.dtd"> l#qv 5f
{/8Q)2*>0
<xwork> @g-Tk
diT=x52
<package name="user" extends="webwork- QlZ@ To
)"<8K}%!
interceptors"> \}"m'(\c
k$i'v:c|:i
<!-- The default interceptor stack name m$2<`C=
EbQa?
--> n1v5Q2xw
<default-interceptor-ref Dr#c)P~Wd
$)Bg JDr
name="myDefaultWebStack"/> svhI3"r
rofNZ;nu
<action name="listUser" aX6}6zubr
L^`}J7r
class="com.adt.action.user.ListUser"> dK9Zg,DZL
<param Yl^mAS[w&
A[N{
name="page.everyPage">10</param> 3iNkoBCg
<result W;_E 4
iz[gHB
name="success">/user/user_list.jsp</result> Bi%x`4Lf
</action> \Y|*Nee}XP
V"KS[>>f
</package> zTm]AG|0
7<\C?`q"
</xwork> x!<yT?A
QG
gF|c7
FY3IUG
X` YwP/D
*ZCn8m:-+
evuZY X@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 >bo'Y9C
%VNlXHO.
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 2\<.0
b{7E;KyY,
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Wd,a?31|
)6X.Nfkb^k
R
W/z1
Fj
p.T;
1OaXo!
我写的一个用于分页的类,用了泛型了,hoho (g!p>m!Z
ib6^x:HGU
java代码: tOl e>]
J>vMo@
2 ][DZl
package com.intokr.util; 3,X/,'
6=GZLpv
import java.util.List; ._Zt=jB
u,.3
/** o2H1N~e#c
* 用于分页的类<br> a}yXC<}$
* 可以用于传递查询的结果也可以用于传送查询的参数<br> PXKJ^fa
* si4-3eC
* @version 0.01 V>-b`e
* @author cheng 7*+]wEs
*/ 7*o*6,/
public class Paginator<E> { D=f7NVc >Q
privateint count = 0; // 总记录数 <=K qcHb
privateint p = 1; // 页编号 LaFZ?7@|}
privateint num = 20; // 每页的记录数 3Hi+Z}8
privateList<E> results = null; // 结果 p/6zEZ*
[IZM.r`Z
/** X@N$Z{
* 结果总数 f>j wN@(
*/ 2!1.E5.I
publicint getCount(){ vsB*rP=
return count; XKOUQc4!R
} R{YzH56M
='?:z2lJ
publicvoid setCount(int count){ Q[n\R@
this.count = count; TA18 gq
} 6aO2:|:yP
)EM7,xMz
/** +!t}
* 本结果所在的页码,从1开始 }CL"S_>1
* &jA\hg#9
* @return Returns the pageNo. gbBy/_b
*/ W[bmzvJ_X
publicint getP(){ ;E;To\NCYF
return p; E`\8TqO
} C2U~=q>>
rt-\g1x
/** &$FvWFRh#
* if(p<=0) p=1 nv0@xnbz
* -XK0KYhgW
* @param p F4#g?R::U
*/ YB))S!;Ok
publicvoid setP(int p){ ^WYQ]@rh3
if(p <= 0) QWnndI_4p
p = 1; R@Y=o].2
this.p = p; MZv]s
} UM%o\BiO
FjfN3#qlg
/** 9W7#u}Z
* 每页记录数量 j|fd-<ng
*/ le)DgIT>=
publicint getNum(){ 8ip7^
return num; 5MTgK=c
} Lm*VN~2
CJknJn3m&
/** I+
l% Sn#\
* if(num<1) num=1 ^>&k]T`
*/ NUJ~YWO;
publicvoid setNum(int num){ Wl"0m1G
if(num < 1) t G.(flW,
num = 1; m4w')r~
this.num = num; )emOKS
} t@oK~ Nr
`iKj
/** * A|-KKo\
* 获得总页数 W`rNBfG>
*/ p0p4Xh1e
publicint getPageNum(){ 'XOX@UH d
return(count - 1) / num + 1; 8iQ[9
} Cr/`keR
EOKzzX7 S
/** Iry
* 获得本页的开始编号,为 (p-1)*num+1 4NR@u\S
*/ G\gMC
<3
publicint getStart(){ A1Y7;-D
return(p - 1) * num + 1; zdun,`6
} )vB2!H/
!<@J6??a}s
/** h&@R| N
* @return Returns the results. F51.N{'
*/ `\Ku]6J]5
publicList<E> getResults(){ ~}ml*<z@
return results; *!e(A ]&
} Rhzn/\)|
I3S9Us-\
public void setResults(List<E> results){ 1n*W2:,z
this.results = results; (WlIwKP
} =ziwxIo6
rEZ8eeB[3
public String toString(){ N)8HR9[!
StringBuilder buff = new StringBuilder )x,8D ~p'
'rP]Nw
(); ;(6g\'m
buff.append("{"); Rs& @4_D
buff.append("count:").append(count); xgsjm))
buff.append(",p:").append(p); "$HbK
@]!h
buff.append(",nump:").append(num); ?wpB`
buff.append(",results:").append }A$WO{2
s Wjy6;
(results); ({}( qm
buff.append("}"); 3B0lb"e
return buff.toString(); [t]X/O3<
} f2)XP$:
he3SR@\T
} rd|uz4d
Z^KA
bBxw#_3A?E