Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [;Jq=G8&t
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %l3f .
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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 [ <j4w
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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 P&h]uNu
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分页支持类: cR=o!2O
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java代码: B"rO
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package com.javaeye.common.util; P
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import java.util.List; AqT}^fS
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publicclass PaginationSupport { XG E.*aI
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publicfinalstaticint PAGESIZE = 30; 7$v_#ZE.H
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privateint pageSize = PAGESIZE; XM)
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privateList items; VsDY,=Ww
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privateint totalCount; WFTwFm6
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privateint[] indexes = newint[0]; s &f\gp1
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privateint startIndex = 0; ')TS'p,n
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public PaginationSupport(List items, int 2AW*PDncxP
{(l,Uhxl""
totalCount){ GHO6$iM)[
setPageSize(PAGESIZE); (v&iXD5t
setTotalCount(totalCount); (3 Z;c_N
setItems(items); !xU[BCbfYV
setStartIndex(0); 7b7WQ 7u
} !8Y A1 o
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public PaginationSupport(List items, int + (Jh$b_
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totalCount, int startIndex){ ;?y~ h$
setPageSize(PAGESIZE); x->+wJm@s
setTotalCount(totalCount); }tQ^ch; Q
setItems(items); _:%i6c*"
setStartIndex(startIndex); d(K}v\3!
} Z^J7r&\V
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public PaginationSupport(List items, int >2ha6A[
2|&SG3e+(I
totalCount, int pageSize, int startIndex){ MS]Q\g}U
setPageSize(pageSize); 6(>,qt,9S
setTotalCount(totalCount); Fd<eh(g9P
setItems(items); JL[!8NyU
setStartIndex(startIndex); a+j"8tHu$
} O"#/>hmv-
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publicList getItems(){ <O.|pJus
return items; e|q~t
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} TkVqv v
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publicvoid setItems(List items){ mNsd&Rk'
this.items = items; uDLj*U6L
} TuC
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publicint getPageSize(){ ijDXh y
return pageSize; }qR6=J+Dx
} #|T2`uYotf
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publicvoid setPageSize(int pageSize){ !Sl_qL
this.pageSize = pageSize; }D-jTZlC
} '.jYu7
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publicint getTotalCount(){ lqmr`\@)
return totalCount; Ir=G\/A
} +.g j/uy*
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publicvoid setTotalCount(int totalCount){ VB`% u=
if(totalCount > 0){ fYW9Zbov-
this.totalCount = totalCount; n:f&4uKoG<
int count = totalCount / =G !]_d0
^9><qKbO
pageSize; |7Qe{
if(totalCount % pageSize > 0) \Yn0|j>
count++; 5~d=,;yE
indexes = newint[count]; pK ^$^*#
for(int i = 0; i < count; i++){ zRgAmX/g
indexes = pageSize * r7^v@
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i; R\<d&+q@
} XM#nb$gl
}else{ ]^Xj!01~
this.totalCount = 0; T=RabKVYP
} qFl|q0\ A
} Xkk 8#Y":
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publicint[] getIndexes(){ =\mJ5v"hA
return indexes; TM|PwY
} ?<S fhjU
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publicvoid setIndexes(int[] indexes){ [7 NO !^
this.indexes = indexes; QKhGEW~G
}
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publicint getStartIndex(){ Z:^ S-h
return startIndex; 2H`>Kj
} ~,Yd.?.TI
IfT: 9
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publicvoid setStartIndex(int startIndex){ Q3Y(K\
if(totalCount <= 0) dkqyn"^
this.startIndex = 0; c?KIHZ0
elseif(startIndex >= totalCount) #<s"?Y%-
this.startIndex = indexes @}Q!K*
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[indexes.length - 1]; X\>/'fC$
elseif(startIndex < 0) qz.l
this.startIndex = 0; U$S{j&?
else{ }0f~hL24
this.startIndex = indexes KUpj.[5qo
g9=_^^Tg
[startIndex / pageSize]; \}X[0ct2!
} >
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} ^8YBW<9
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publicint getNextIndex(){ a8gOb6qF/H
int nextIndex = getStartIndex() + ;/kmV~KG
H}q$6WE
pageSize; )3<>H!yG}
if(nextIndex >= totalCount) 5X9L h_p
return getStartIndex(); 8'NT_NPNb
else
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return nextIndex; -f1lu*3\
} [)kuu
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publicint getPreviousIndex(){ ( uG;Q
int previousIndex = getStartIndex() - m&z(2yb1
'=eVem=
pageSize; fJ6Q:7
if(previousIndex < 0) $*LBZcL
return0; sZ7~AJ
else j)#yyK{k2s
return previousIndex; 7j29wvSp5
} @1' Y/dCyD
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} ZE=
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抽象业务类 e}P@7e h
java代码:
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/** )vpYVr-
* Created on 2005-7-12 wQ~]VVRN
*/ ggm'9|
package com.javaeye.common.business; lL
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import java.io.Serializable; gv D*^
import java.util.List; kP5G}Bp
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import org.hibernate.Criteria; I Gi9YpI&K
import org.hibernate.HibernateException; 1 o_6WU
import org.hibernate.Session; g \ou+M#
import org.hibernate.criterion.DetachedCriteria; kbJ4CF}H
import org.hibernate.criterion.Projections; B6KG\,'|
import YW&`PJ9o
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org.springframework.orm.hibernate3.HibernateCallback; z-:>[Sn
import Hs_7oy|P
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org.springframework.orm.hibernate3.support.HibernateDaoS Rha|Rk~
3N|6?'m
upport; /Ahh6=qQY
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import com.javaeye.common.util.PaginationSupport; nR w f;K
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public abstract class AbstractManager extends Q1x15pVku/
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HibernateDaoSupport { s:(z;cj/
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privateboolean cacheQueries = false; _OS,zZ0
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privateString queryCacheRegion; EJQT\c
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publicvoid setCacheQueries(boolean +_u~Np
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cacheQueries){ Fs(S!;
this.cacheQueries = cacheQueries; "dE[X`
}=
} 7,8TMd1`M
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publicvoid setQueryCacheRegion(String pYu6[
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queryCacheRegion){ q_mxZM
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this.queryCacheRegion = 3-)}.8F
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queryCacheRegion; g5u4|+70
} LafBf6wds
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publicvoid save(finalObject entity){ 8G9( )UF.
getHibernateTemplate().save(entity); %+<1X?;,Fq
} #};Zgixo$
};EB[n
publicvoid persist(finalObject entity){ 065 =I+Vo
getHibernateTemplate().save(entity); 0PsQ
1[1
} DyA/!%g
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publicvoid update(finalObject entity){ fny6`_O
getHibernateTemplate().update(entity); M)AvcZNs
} zK{}
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publicvoid delete(finalObject entity){ r.6?|
getHibernateTemplate().delete(entity); ,?Zy4-
} 53pT{2]zAi
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@
publicObject load(finalClass entity, 79-50}A
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finalSerializable id){ }UQ,B
return getHibernateTemplate().load @LDs$"f9=
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(entity, id); qDhZC*"9#D
} X8?@Y@
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publicObject get(finalClass entity, DUH_LnHw)
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finalSerializable id){ Dhfor+Epy
return getHibernateTemplate().get 6pfkv2.}
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(entity, id); ~l{Qz0&
} W}}ZP];
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publicList findAll(finalClass entity){ nZc6
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return getHibernateTemplate().find("from m_BpY9c]5
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" + entity.getName()); C8)Paop$
} Aayd3Ph0%
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publicList findByNamedQuery(finalString {;zHkmx
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namedQuery){ _x#y
return getHibernateTemplate bAuiMw7!
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().findByNamedQuery(namedQuery); }d iE'
} %L7DC`
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publicList findByNamedQuery(finalString query, .;.Zbhm
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finalObject parameter){ 4xg1[Z%:
return getHibernateTemplate Bss*-K]
* LWihal
().findByNamedQuery(query, parameter); p>:.js5.a
} ?i\V^3S n$
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publicList findByNamedQuery(finalString query, !M9mX%UQ
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finalObject[] parameters){ aI`d
return getHibernateTemplate Yl?s^]SFU
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().findByNamedQuery(query, parameters); cfg.&P>
} BM)a,fIgo
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publicList find(finalString query){ N2k{@DY
return getHibernateTemplate().find A )CsF
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(query); '&K' 0qG
} !W0JT#0
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publicList find(finalString query, finalObject \u[5O@v#
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parameter){ CRrEs
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return getHibernateTemplate().find IB 4L(n1
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(query, parameter); =?wDQ:
} QR8]d1+GV
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public PaginationSupport findPageByCriteria PU B0H
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(final DetachedCriteria detachedCriteria){ ^8-,S[az
return findPageByCriteria f;l}Z|dok6
{)!ua7GF0H
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5nceOG8
} Nlwt}7
qD=b+\F
public PaginationSupport findPageByCriteria CWYOzqf
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(final DetachedCriteria detachedCriteria, finalint ]~f-8!$$R
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startIndex){ MTgf.
return findPageByCriteria |UQ[pas
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(detachedCriteria, PaginationSupport.PAGESIZE, .'2I9P\!
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startIndex); D;+Y0B
} {Dy,|}7s
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public PaginationSupport findPageByCriteria .W2w/RayC
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(final DetachedCriteria detachedCriteria, finalint QyZ'%T5J
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pageSize, XbFo#Pwk
finalint startIndex){ @ptrF
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return(PaginationSupport) 9(vp`Z8B4
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getHibernateTemplate().execute(new HibernateCallback(){ E piF$n
publicObject doInHibernate 'xaEG,P
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(Session session)throws HibernateException { S==0/
Criteria criteria = dXsL0r*c
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detachedCriteria.getExecutableCriteria(session); iXXaB+w
int totalCount = Xqew~R^MP
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((Integer) criteria.setProjection(Projections.rowCount }S13]Kk?=
1Ak0A6E
()).uniqueResult()).intValue(); een62-`
criteria.setProjection VAyAXN~
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(null); 4 EA$<n(A-
List items = 7*Zm{r@u
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criteria.setFirstResult(startIndex).setMaxResults L5 Ai
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(pageSize).list(); hg'eSU$J
PaginationSupport ps = ^%g8OP
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new PaginationSupport(items, totalCount, pageSize, J\'f5)k
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startIndex); cP@H8|c=
return ps; HAs/f#zAk6
} 1L\r:mx3
}, true); Py+ B 2G|
} q9InO]s&~=
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public List findAllByCriteria(final Pmr'W\aIR
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DetachedCriteria detachedCriteria){ 4U'sBaY!K
return(List) getHibernateTemplate 4ISIg\:c*
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().execute(new HibernateCallback(){ I!K-*
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publicObject doInHibernate G'nSnw
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(Session session)throws HibernateException { I\j-
Criteria criteria = w&]$!g4
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detachedCriteria.getExecutableCriteria(session); H{EZ} *{M4
return criteria.list(); 4wa3$Pk
} .6bo
}, true); b0se-#+
} 07ppq?,y
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public int getCountByCriteria(final ^d(gC%+!u
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DetachedCriteria detachedCriteria){ )QnsRW{D"
Integer count = (Integer) XJq]l6a:
$h=v;1"
getHibernateTemplate().execute(new HibernateCallback(){ vJx( lU`Y
publicObject doInHibernate 8Vt'X2
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(Session session)throws HibernateException { hW;n^\lF#e
Criteria criteria = mOLz(0
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detachedCriteria.getExecutableCriteria(session); j4=\MK
return ;LKYA?=/V
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criteria.setProjection(Projections.rowCount a^O>i#i
^b= ;
()).uniqueResult(); yRQNmR;Uy
} #}tdA(
-
}, true); X1V~.kvt)
return count.intValue(); hOdU%
} 2G3Hi;q18
} ^R7X!tOq4
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用户在web层构造查询条件detachedCriteria,和可选的 ?TmVLny
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 tWTC'Gx-J
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PaginationSupport的实例ps。 bIV9cpW
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ps.getItems()得到已分页好的结果集 l$W)Vk<B(T
ps.getIndexes()得到分页索引的数组 ?1eu9; q\*
ps.getTotalCount()得到总结果数 r,L`@A=v
ps.getStartIndex()当前分页索引 a
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ps.getNextIndex()下一页索引 7+6I~&x!Lz
ps.getPreviousIndex()上一页索引 7WmY:g#s
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }C~9?Y
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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 |H5$VSw
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一下代码重构了。 MY(51)*
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我把原本我的做法也提供出来供大家讨论吧: |Fq\%y#
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首先,为了实现分页查询,我封装了一个Page类: 'RV wxd
java代码: A43[i@o
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/*Created on 2005-4-14*/ {L M Q
package org.flyware.util.page; 2B_+5
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/** ]^@m $O
* @author Joa i+I1h=
* MOuEsm;
*/ O8LIKD_I[
publicclass Page { D8$4P T0u
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/** imply if the page has previous page */ <jLL2-5r0
privateboolean hasPrePage; 9h6siK(F
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/** imply if the page has next page */ C2DAsSw
privateboolean hasNextPage; GAh\6ul
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/** the number of every page */ 8Qkwg]X
privateint everyPage; OY!WEP$F-C
JbXi|OS/
/** the total page number */ F C=N}5u
privateint totalPage; 9*r l7
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/** the number of current page */ > aCY
privateint currentPage; 5R1?jlm
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/** the begin index of the records by the current }|znQ3A2\l
l
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query */ ;g<y{o"Q3p
privateint beginIndex; OgCNqW
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/** The default constructor */ e
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public Page(){ YH{n
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} g}*p(Tp9:
)k4&S{=
/** construct the page by everyPage ~!/a gLwY
* @param everyPage ?H8dyQ5"
* */ ]tmMk7
public Page(int everyPage){ :y_]JL;w
this.everyPage = everyPage; *nV"X0&
} g$qM}#s0}
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, (/!zHq
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int everyPage, int totalPage, 5wv7]F<
int currentPage, int beginIndex){ |jcIn[)=
this.hasPrePage = hasPrePage; V&lx0Dy
this.hasNextPage = hasNextPage; 6Z@T
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this.everyPage = everyPage; \[wbJ
this.totalPage = totalPage; Ghar
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this.currentPage = currentPage; d8p5a
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this.beginIndex = beginIndex; qGP}
} I(Vg
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/** pK0@H "$8
* @return LFvZ 7M\\
* Returns the beginIndex. 9)4_@rf%
*/ jQ-2SA O
publicint getBeginIndex(){ +Y>oNX1KN
return beginIndex; ]y"=/Nu-Ja
}
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8,&Y\b`..
/** C8}
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* @param beginIndex |vxmgX)
* The beginIndex to set. bfK4ps}m*
*/ lLU8eHf\
publicvoid setBeginIndex(int beginIndex){ }!m}?
this.beginIndex = beginIndex; mR8tW"Z2
} 8K&=]:(
/.sho\a
/** isFxo,R9r
* @return X-psao0tI`
* Returns the currentPage. w`gT]Rn
*/ 6Q]JY,+
publicint getCurrentPage(){ rshUF
return currentPage; v8C4BuwA
} {~XnmBs
"h8fTB\7S\
/** +R;s<pZ^
* @param currentPage `dRqheX
* The currentPage to set. F;BCSoO4
*/ ,}wFQ9*|W
publicvoid setCurrentPage(int currentPage){ ^S!;snhn
this.currentPage = currentPage; xRqA^Ad
} ]3 QW\k~
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/** {*K$gH$
* @return T*'WS!z
* Returns the everyPage. wGxH
*/ sFsf~|
publicint getEveryPage(){ Xx\,<8Xn
return everyPage; e-b>
} GH`y-Ul'K
4^:$|\?]
/** D/hq~- g
* @param everyPage wNmC1HOh
* The everyPage to set. T>J ,kh
*/ #G=AD/z
publicvoid setEveryPage(int everyPage){ eL{$=Um
this.everyPage = everyPage; DD`DU^o<
} FwD
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/** YWL7.Y>%5
* @return 8i)9ho<
* Returns the hasNextPage. z|\n^ZK=
*/ #er% q:
publicboolean getHasNextPage(){ ^1_CS*
return hasNextPage; Hlpt zez
} {.J<^V
j-ob7(v)*]
/** $xjfW/k?M
* @param hasNextPage PX` xr1o
* The hasNextPage to set. 6E.[F\u
*/ s-~`Ao'
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publicvoid setHasNextPage(boolean hasNextPage){ DgB;6Wl
this.hasNextPage = hasNextPage; _CBMU'V
} `g0^W/j
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/** DhD##5a
* @return m)Wq*&,o
* Returns the hasPrePage. Jm"W+! E
*/ [ 6Sk>j
publicboolean getHasPrePage(){ s_e*jM1
return hasPrePage; mc{W\H
} *vq75k$7
7zIfsb
/** eBY/Y6 R
* @param hasPrePage y9w,Su2
* The hasPrePage to set. }w8yYI
*/ zL'S5'<F|
publicvoid setHasPrePage(boolean hasPrePage){ c c/nzB
this.hasPrePage = hasPrePage; ef/43+F^x
} 1/K1e$r
2<:dA >1
/** !YZKa-
* @return Returns the totalPage. Z'Pe%}3
* #rNc+
*/ UT[{NltH
publicint getTotalPage(){ $xcZ{C
return totalPage; {L [
} 4t3>`x
7
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/** W=OryEV?
* @param totalPage < RtyW
* The totalPage to set. m9+?>/R
*/ PZlPC#E-
publicvoid setTotalPage(int totalPage){ bm4Bq>*=U
this.totalPage = totalPage; kE|x'(x
} T8Q_JQ
Hi*|f!,H?
} '?g&);4)k-
0Ng?U+6
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 VT=gb/W6)a
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个PageUtil,负责对Page对象进行构造: 0rm(i*Q
java代码: o[i*i<jv-
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Mc!LC
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/*Created on 2005-4-14*/ (U_HX2f
package org.flyware.util.page; yK$aVK"
b#R$P]dr=
import org.apache.commons.logging.Log; pS}IU{#;
import org.apache.commons.logging.LogFactory; Upcx@zJ
#,1z=/d.
/** lNl.lI\t)y
* @author Joa %r*,m3d
* 0Ub'=`]5a
*/ RDjw|V
publicclass PageUtil { EuImj#Zl
He}?\C
Bo
privatestaticfinal Log logger = LogFactory.getLog [-\U)>MY(p
.D\oKhV(
(PageUtil.class); 96J]g*o(uU
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/** y`
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* Use the origin page to create a new page lyyf&?2
* @param page foL4s;2
* @param totalRecords GIn%yB'
* @return u0G
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*/ x'..j5
publicstatic Page createPage(Page page, int x%HxM~&
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totalRecords){ g j]8/~lr
return createPage(page.getEveryPage(), 67Qu<9}<-
78~/1-
page.getCurrentPage(), totalRecords); m^3j|'mG
} !
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cMnN} '
/** " a,4E{7
* the basic page utils not including exception !$>b}w'
*+2_!=4V
handler @!O(%0
=
* @param everyPage DT)][V^w
* @param currentPage 8{ =ha
* @param totalRecords ~(huUW
* @return page AXSip
*/ YRr,{[e
publicstatic Page createPage(int everyPage, int 'mTY56Yq
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currentPage, int totalRecords){ M X7Ix{
everyPage = getEveryPage(everyPage); \Q1&w2mw
currentPage = getCurrentPage(currentPage); WVKAA.
int beginIndex = getBeginIndex(everyPage,
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"PO8 Q
currentPage); AI#.+PrC{/
int totalPage = getTotalPage(everyPage, H$ g*
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totalRecords); Y4swMN8Bq
boolean hasNextPage = hasNextPage(currentPage, +zq"dj_
r]DU
totalPage); !MOsP<2
boolean hasPrePage = hasPrePage(currentPage); zUZET'Bm9
5>daWmD
returnnew Page(hasPrePage, hasNextPage, Dj'?12Onu=
everyPage, totalPage, A9u>bWIE7
currentPage, m)"(S
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beginIndex); kR^h@@'F"
} -C}"1|P!
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privatestaticint getEveryPage(int everyPage){ JX[]u<h?
return everyPage == 0 ? 10 : everyPage; (xVx|:R[<H
} <eS/-W%n6
wVnmT94
privatestaticint getCurrentPage(int currentPage){ T]tu#h{
a
return currentPage == 0 ? 1 : currentPage; w?^[*_Y
} VNIl%9:-l
Q^nfD
privatestaticint getBeginIndex(int everyPage, int cfa1"u""e
B@0#*I
Rm
currentPage){ ~> lqEa
return(currentPage - 1) * everyPage; "VSx?74q
} Ak('4j!*}^
YM'4=BlJHv
privatestaticint getTotalPage(int everyPage, int CI$z+zN
/2c(6h
totalRecords){ s@7h oU-+
int totalPage = 0; C4.GtY8,d
K%mR=u#%&
if(totalRecords % everyPage == 0) Y,Rr[i"j
totalPage = totalRecords / everyPage; G)t-W%D&
else q/ 54=8*h0
totalPage = totalRecords / everyPage + 1 ; nXoDI1<[
5;p|iT
return totalPage; S7nx4c2xK~
} q oi21mCn
|pWu|M _'
privatestaticboolean hasPrePage(int currentPage){ m*N8!1Ot
return currentPage == 1 ? false : true; ~n%Lo3RiP
} ) 5$?e
~+Pe=~a[
privatestaticboolean hasNextPage(int currentPage, JJ}DYv
r hucBm
int totalPage){ Og1vD5a
return currentPage == totalPage || totalPage == $ B&ZnZ?
EA8plQ~GtE
0 ? false : true; 0zSz[;A
} NW`.7'aWT
U.P1KRY|=
0:u:#))1
} nQ+5jGP1
FjtS
k_wcol,W
bo\Ah/.
Q*PcO \Y!y
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。 I#O"<0
*r
a~_JTH4=t
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 ]YFjz/f
.IdbaH
_a
做法如下: 4* >j:1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )?(Ux1:w)
ln=fq:
的信息,和一个结果集List: EC[]L'IL
java代码: :adz~L$
OQKg/1
5>0\=
/*Created on 2005-6-13*/ js <Up/1
package com.adt.bo; @_-,Q5
>Jx=k"Kv+
import java.util.List; GF%/q :9
uK"FopUJ4i
import org.flyware.util.page.Page; 'F.P93
W4 d32+V
/** Ti_G
* @author Joa \X%FM"r
*/ ``VE<:2+
publicclass Result { i.)n#@M2
!<=zFy[J.9
private Page page; n(eo_.W2|
UhS:tT]7
private List content; $o5i15Oy.
l:UKU !
/** 0{bl^#$f
* The default constructor Er~KX3vF
*/ W7
Iy _>
public Result(){ ut560,h~
super(); C{uT1`
} }kvix{
$[fq Th
/** 8_HBcZWs
* The constructor using fields T:{r*zLSN
* [(#)9/3,
* @param page # M/n\em"X
* @param content Wd)\r.pJ
*/ $Uy+]9
public Result(Page page, List content){ nTr]NBR
this.page = page; M3@qhEf?vk
this.content = content; s<!G2~T
} w[gt9]}N
+z?gf*G_W'
/** /Z^a,%1
* @return Returns the content. 87l*Y|osP
*/ )/)u.$pi
publicList getContent(){ W#P\hx
return content; [ R+M .5
} {zm8`
A"b31*_
/** N'EZJoH
* @return Returns the page. U- 1UWq
*/ !fn%Q'S
public Page getPage(){ H<i!C|AF
return page; E:**gvfq
} 8o%Vn'^t
K\U`gTGc
/** IMqe(
* @param content [iq^'E
* The content to set. E#rQJ
*/ vMou`[\WlJ
public void setContent(List content){ ,s3|
this.content = content; aXVldt'
} WcKDerc
qX-5/;n
/** Ah7"qv'L\
* @param page )?#K0o[<
* The page to set. `&q+ f+z
*/ {u1|`=;
publicvoid setPage(Page page){ Lr*PbjQDIY
this.page = page; :K2
X~Ty
} $#D#ezvxe
} ~"`e9Im
hjg1By(
.p e3L7g
Q34u>VkdQI
gF)-Ci
2. 编写业务逻辑接口,并实现它(UserManager, `f~bnL
j`.&4.7+
UserManagerImpl) #
f-hI
java代码: 3R%JmLM+R9
>KrI}>!9r
o ;Z"I &
/*Created on 2005-7-15*/ 1K@ieVc
package com.adt.service; \os"w "
3<$Ek3X
import net.sf.hibernate.HibernateException; (!{*@?S
U~ a\v8l~
import org.flyware.util.page.Page; @Drl5C}+
SQK82/
import com.adt.bo.Result; 8ly)G
K(upzn*a
/** us|Hb
* @author Joa 1DcBF@3sWG
*/ Q}B]b-c+E
publicinterface UserManager { \a;xJzc9
>Df;1:U
public Result listUser(Page page)throws ]m 3cm
hIqU idJod
HibernateException; N80ogio_Tk
AA,/AKikd
} nD
eVY K
Het"x
oA-,>:}g{
R~a9}&
o#wly%i')
java代码: @uRJl$3
d5Ae67
Gy):hGgN
/*Created on 2005-7-15*/ @,sjM]
package com.adt.service.impl; aB;f*x
s1cu5eCt
import java.util.List; \w1XOm [)
`x
_(EZ
import net.sf.hibernate.HibernateException; Z9M$*Zp
)Hin{~h
import org.flyware.util.page.Page; rMIX{K)'f
import org.flyware.util.page.PageUtil; [UzacX t
B6IKD
import com.adt.bo.Result; nm<VcCc
import com.adt.dao.UserDAO; c$ib-
import com.adt.exception.ObjectNotFoundException;
V^Z5i]zT
import com.adt.service.UserManager; rM= :{
Lwi"K8.u
/** ^TZmc{i
* @author Joa hL/u5h%$
*/ z~`X4Segw
publicclass UserManagerImpl implements UserManager { dI%jR&.e;
ZPE-
private UserDAO userDAO; em,1Yn?
d*Mqs}8
/** fNAW4I I}
* @param userDAO The userDAO to set. $[`rY D/.
*/ F%p DF\
publicvoid setUserDAO(UserDAO userDAO){ ["&{^
this.userDAO = userDAO; }Em{?Hqy
} 00i MU
Ddq*}Pf0K
/* (non-Javadoc) J2x}@p
* @see com.adt.service.UserManager#listUser 9b=0
4aWHm
xP>cQEL ot
(org.flyware.util.page.Page) GNM>hQ)h:
*/ w]qM
public Result listUser(Page page)throws KZg2`8F
z0+JMZ/
HibernateException, ObjectNotFoundException { g9^\QYh!
int totalRecords = userDAO.getUserCount(); lFtEQ '}
if(totalRecords == 0) <FBH;}]
throw new ObjectNotFoundException Fl($0}ER
o[KZm17
("userNotExist"); :t`W&z41
page = PageUtil.createPage(page, totalRecords); p({@t=L3g
List users = userDAO.getUserByPage(page); sdO8;v>
returnnew Result(page, users); p: z][I
} #Swc>jYc
0!YVRit\N
} Hl%Og$q3
fh)eL<I
E-Xz
R2~y<^.V`Y
5>%^"f
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 U`3?bhzua
x^)?V7[t
询,接下来编写UserDAO的代码: xa'U_]m
3. UserDAO 和 UserDAOImpl: V#$QKn`;
java代码: fgL"\d}
,sc#l<v
xV+\R/)x
/*Created on 2005-7-15*/ 4rL`||
package com.adt.dao; /q>ExXsEC
Eu&$Rq}
import java.util.List; ) q'D9x9
'+$r7?dKP
import org.flyware.util.page.Page; 9c}C<s`M
E<-W & a }
import net.sf.hibernate.HibernateException; zP0<4E$M`
4$vUD1('
/** XQ[\K6X5
* @author Joa ] H;E(1iU
*/ @BnK C&{
publicinterface UserDAO extends BaseDAO { NVkYm+J#
6<\dQ+~
publicList getUserByName(String name)throws rMJ@oc
~.^:?yCA
HibernateException; m=E/um[D
nT=%3_.
publicint getUserCount()throws HibernateException; \6a' p
Q,
rU9")4sQ
publicList getUserByPage(Page page)throws PO'K?hVS^w
r]xN&Ne5Q
HibernateException; 1&e8vVN
]!S#[Wt {k
} }03?eWk/y
<!G /&T
sdCG}..`
V}<<?_
:,p3&2I
java代码: 3v3cK1K@oE
7^rT-f07
@eBo7#Zr
/*Created on 2005-7-15*/ \M.?*p
package com.adt.dao.impl; 4Yok,<
dbEXlm
import java.util.List; EmUt/]
\NDW@!X
import org.flyware.util.page.Page; AX{<d@z`j
rT;l#<#VE
import net.sf.hibernate.HibernateException; qOpwl*?x+
import net.sf.hibernate.Query; }T}c%p
emJZ+:%
import com.adt.dao.UserDAO; "dndhoMq
w_`;Mn%p
/** fuHNsrNlm
* @author Joa #+6j-^<_6
*/ 7W},5c
public class UserDAOImpl extends BaseDAOHibernateImpl 7`L]aRS[
3_;=y\F
implements UserDAO { ?\4kV*/Cqz
$Nvox<d0
/* (non-Javadoc) )2W7>PY
* @see com.adt.dao.UserDAO#getUserByName -u~:Gd*l0
?S=y>b9R
(java.lang.String) dmkGIg}
*/ I31Nu{
publicList getUserByName(String name)throws 9b-4BON{P
%<Qv?`B
HibernateException { &=%M("IlD
String querySentence = "FROM user in class ;A"i.:ZT
q2B'R
com.adt.po.User WHERE user.name=:name"; wH=7pS"s
Query query = getSession().createQuery Bf^K?:r"V
''9K(p6
(querySentence); \Qnr0t@0
query.setParameter("name", name); 2|exY>`w
return query.list(); m|?1HCRXRI
} V0,5c`H c
2HE<WI^#h
/* (non-Javadoc) X eis_
* @see com.adt.dao.UserDAO#getUserCount() [=.iJ5,{2
*/ 1GR|$E
publicint getUserCount()throws HibernateException { &?@U_emLi
int count = 0; fRk'\jzT
String querySentence = "SELECT count(*) FROM %T<c8w}dP
1M_6X7PH
user in class com.adt.po.User"; [}Rs
Query query = getSession().createQuery .{;RJ:O
>PdrLwKS
(querySentence); pkG8g5(w
count = ((Integer)query.iterate().next BB1_EdoG
2^5RQl/
()).intValue(); C)qG<PW.!
return count; k?3mFWc
} ^N ;TCn
th"Aatmp
/* (non-Javadoc) ]B&jMj~y&
* @see com.adt.dao.UserDAO#getUserByPage A#pH$s
*6_>/!ywI
(org.flyware.util.page.Page) fWg3gRI
*/ 7S=]@*
publicList getUserByPage(Page page)throws [ryII hQ
E'+z.~+
HibernateException { xw~oR|`U
String querySentence = "FROM user in class z:Ru`
(i<\n`h1K
com.adt.po.User"; ZLP0SCkuR
Query query = getSession().createQuery i-95>ff
8*VQw?{Uee
(querySentence); c2gZ<[~
query.setFirstResult(page.getBeginIndex()) .ArOZ{lKD>
.setMaxResults(page.getEveryPage()); 0"sZP\<p
return query.list(); 54]UfmT%I
} L)H/t6}i
'UCClj;?K
} j6*e^
B
Xe
^NVF
h^H)p`[Gme
A}uWy^w
#x6wM~
至此,一个完整的分页程序完成。前台的只需要调用 X*)DpbWd
L`w_Q2{sv
userManager.listUser(page)即可得到一个Page对象和结果集对象 [4])\q^q
HR'F
的综合体,而传入的参数page对象则可以由前台传入,如果用 6_w~#86=
UY\E uA9
webwork,甚至可以直接在配置文件中指定。 +OInf_O
loyhNT=
下面给出一个webwork调用示例: a|dn3R>vX
java代码: +9;6]4
/5>A 2y
\3rgwbF
/*Created on 2005-6-17*/ T%TO?[cN
package com.adt.action.user; oSR;Im<2
0w2<2grQ
import java.util.List; H7 {kl
}mk z_P(Z
import org.apache.commons.logging.Log; (
~>-6Nb 5
import org.apache.commons.logging.LogFactory; /dR:\ffz2
import org.flyware.util.page.Page; a8y*Jz-E
-?)z@Lc
import com.adt.bo.Result; ZoqE,ucH
import com.adt.service.UserService; 6099w0fR`
import com.opensymphony.xwork.Action; *2m{i:3
#("E)P
/** 5G#2#Al(F
* @author Joa ~f8:sDJ
*/ 8hX/~-H
publicclass ListUser implementsAction{ SmP&wNHQf
@Rqn&tA8
privatestaticfinal Log logger = LogFactory.getLog k#5Qwxu`
&x[V<Gq
(ListUser.class); :{#w-oC>6P
a0wpsl
iF
private UserService userService; )*BG-nM u
jpiBHi]5+
private Page page; EBUCG"e
FbD9G6h5
privateList users; NrcxuItkYn
t8#u}u
/* +=L^h9F
* (non-Javadoc) Cj6$W5I m
* thh0~g0/
* @see com.opensymphony.xwork.Action#execute() AHP;N6Y6
*/ n--s[Kdo8
publicString execute()throwsException{ [:{HX U7y
Result result = userService.listUser(page); U,\t2z
page = result.getPage(); |198A,^
users = result.getContent(); ZlL]AD@
return SUCCESS; F^wm&:%{`
} D'_w
*
7}fT7tsN
/** K3J,f2Cn$
* @return Returns the page. g % 8@pjk
*/ MF5o\-&dN
public Page getPage(){ E^Z?X2Z
return page; >s;dooZ
} 7Y1FFw|
@_"Z]Y ,D0
/** h`MTB!o
* @return Returns the users. srIt_Wq
*/ ^#z*
publicList getUsers(){ vq5o?$:-
return users; -h&KC{Xab
} {=T9_c
ALp|fZ\vp
/** )#025>$z
* @param page =D^R,Q
* The page to set. J+Zp<Wu-
*/ z7O$o/E-*
publicvoid setPage(Page page){ s>e)\9c
this.page = page; m+dJ3
} 9.l*#A^
ys}I~MK -
/** EpH\;25u
* @param users z CFXQi
* The users to set. Jw
-3G3h
*/ Ibu 5
publicvoid setUsers(List users){ r[KX"U-
this.users = users; ;Z-%'5hKM
} p']oy;t
qbD[<T
/** IFW"SfdZk
* @param userService :sJQ r._L
* The userService to set. $36.*s m
*/ pn
aSOyR
publicvoid setUserService(UserService userService){ /9@VnM
this.userService = userService; @A8@j%CK1
} j4]y(AA
} sk~inIj-
63pd W/\j
p2(Z(V7*
L<ET"&b;4
LZ1)zoJ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, %bgUU|CdA
Kr@6m80E5
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 =$F<Ac;&
8@d@T V!n&
么只需要: 2X@" #wIg
java代码: Hie
?!$:I8T
sH+ 90|?
<?xml version="1.0"?> Ws:MbZyr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6[&x7"
=]W[{@P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- f2Z(hYH~
9%^O-8!
1.0.dtd"> ?4YLt|sn
\vqqs
<xwork> k[5:]5lp+
E8b:MY
<package name="user" extends="webwork- C?t!Uvs
^_G@a,
interceptors"> gE~LPwM
ow K)]t
<!-- The default interceptor stack name `-w;/A"MJ
4~z-&>%
--> H[U"eS."
<default-interceptor-ref NWII?X#T}
L_R(K89w
name="myDefaultWebStack"/> o'|B|oZ
a<lDT_2b
<action name="listUser" 7&vDx=W
"g&hsp+i"A
class="com.adt.action.user.ListUser"> wg]VG,
<param Oc%W_Gb7
*apkw5B}C
name="page.everyPage">10</param> zx;~sUR;
<result U,7}VdO
jUd)|v+t
name="success">/user/user_list.jsp</result> <^Jdl.G
</action> M^ jEp
-qdt$jIM
</package> L4or*C^3
B PG&R
</xwork> WM9z~z'2a
EM,=R
CX#d9
8\b
7(C:ty9
w7b\?]}@
WlmkM?@
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 my%MXTm2
p'\zL:3
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。 _[$,WuG1
\"6?*L|]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 C!W0L`r
k[{ ~eN:
~ ;ObT=
|X;|=.
Y |9
我写的一个用于分页的类,用了泛型了,hoho 0?O$->t
b!`{fwV
java代码: Cm;M;
?
/n1L},67h
Q+ZZwqyxD
package com.intokr.util; hd@jm^k
N."x@mV
import java.util.List; d8K|uEHVz
.:~E.b
/** z"f+;1
* 用于分页的类<br> %BF,;(P
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ]D[\l$(
* T}59m;I
* @version 0.01 "w3%BbI x
* @author cheng (h'Bz6K
*/ r0*Y~
KHw
public class Paginator<E> { ;2[),k
privateint count = 0; // 总记录数 o2!wz8
privateint p = 1; // 页编号 6o4Y]C2W{1
privateint num = 20; // 每页的记录数 BJKv9x1jK
privateList<E> results = null; // 结果 DGNn#DP
P~s u]+
/** D.gD4g_O/
* 结果总数 !wTrWD!
*/ zZ;V9KM>v
publicint getCount(){ &pW2R}
return count; J;'H],w}f
} 5}Z>N,4
fGoJP[ae
publicvoid setCount(int count){ wU|jw(
this.count = count; ic}mru
} k%VYAON
p4D.nB8
/** JT6}m
* 本结果所在的页码,从1开始 h 27f0x9
* 6B+?X5-6DH
* @return Returns the pageNo. nWA>u J5
*/ w@pJ49
publicint getP(){ /QT>"
return p; P=l 7m*m
} *P8CzF^>\&
/}9)ZYMx
/** )YW"Zo8~!1
* if(p<=0) p=1 Wg,7k9I
* wsB
* @param p .q1y)l-^Z
*/ %<fs \J^k
publicvoid setP(int p){ >R5A@0@d5
if(p <= 0) 8Oz9 UcG
p = 1; 6Ta+f3V
this.p = p; <<R2
X1
} w |abaMam
7^tYtMm|U
/** YdyTt5-
* 每页记录数量 WtO@Kf:3GH
*/ =\G`g#
publicint getNum(){ ~RLWr.pK
return num; @0(%ayi2Y
} WyRSy-{U(}
H!'4A&
/** F}=_"IkZ
* if(num<1) num=1 udmLHc
*/ L7R!,
publicvoid setNum(int num){ 'KDt%?24
if(num < 1) 3aU5rbi|B
num = 1; t~<HFY*w
this.num = num; ) ]DqK<-
} 0s79rJ
d0R;|p''Z
/** bM.$D-?dF*
* 获得总页数 Rh#`AM`)j
*/ S|af?IW
publicint getPageNum(){ ;hF}"shJN
return(count - 1) / num + 1; z[6avW"q
} a~?B/
g&_
_]-8gr-T
/** U({N'y=
* 获得本页的开始编号,为 (p-1)*num+1 X}Om)WCr
*/ n.t5:SW
publicint getStart(){ ;M~9Yr=1
return(p - 1) * num + 1; a,(nf1@5
}
TO.STK`
6lT< l zT
/** 6TTu[*0NT
* @return Returns the results. aRElk&M
*/ 8!YQ9T [
publicList<E> getResults(){ %!eRR
return results; G|RBwl
} =CO) Q2
B!&y>Z^$
public void setResults(List<E> results){ K1o>>388G
this.results = results; l(Dr@LB~
} `NsQ&G
!&:Cp_
public String toString(){ -<9Qez)y
StringBuilder buff = new StringBuilder /q}(KJX
_>BYUPY
(); OQ4Pk/-'
buff.append("{"); q%QvBN
buff.append("count:").append(count); J5n6K$.d
buff.append(",p:").append(p); Hzj8o3
buff.append(",nump:").append(num); &iZt(XD
buff.append(",results:").append (P;TM1k
K^o{lyK;@~
(results); (EvYrm4
buff.append("}"); bI|{TKKN&P
return buff.toString(); *JfGGI_E
} L>mM6$l
QAt]sat
} d3
i(UN]
:y`LF<
\F-n}Z