Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,M0#?j>
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w$$vR
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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 mvXIh";
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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 Yq0j w&v
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分页支持类: 7-j=he/
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java代码: ZIp"X
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package com.javaeye.common.util; ss'`[QhR2
js F96X{
import java.util.List; JAU:Wqlg1
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publicclass PaginationSupport { `3'4_@7s9
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publicfinalstaticint PAGESIZE = 30; LWIPq"
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privateint pageSize = PAGESIZE; |.{[%OJP
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privateList items; LgJUMR8vUO
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privateint totalCount; ByivV2qd{
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privateint[] indexes = newint[0]; 'eg;)e:`b+
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privateint startIndex = 0; 2>'/!/+R
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public PaginationSupport(List items, int tWa_-Un3
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totalCount){ xa?
setPageSize(PAGESIZE);
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setTotalCount(totalCount); ?X~U[dV?
setItems(items); &? z6f9*$
setStartIndex(0); p^X
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} 2`nOYK
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public PaginationSupport(List items, int 'Ej&zh
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totalCount, int startIndex){ G21cJi*
setPageSize(PAGESIZE); 7yFV.#K3O
setTotalCount(totalCount); c~v(bK
setItems(items); }1?
2
setStartIndex(startIndex); /5r!Fhx
} %bZ}vJ5b
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public PaginationSupport(List items, int !fK9YW(Im
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totalCount, int pageSize, int startIndex){ D.Z4noMA6
setPageSize(pageSize); xyPz_9
setTotalCount(totalCount); C?fa-i0l^
setItems(items); xSL%1>MrN
setStartIndex(startIndex); HN~
} &'A8R;b}-?
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publicList getItems(){ m6YDyQC
return items; o btXtqew
} oa:30@HSb
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publicvoid setItems(List items){ ?n9?`8a#
this.items = items; :}3;z'2]l
} [RFF&uy
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publicint getPageSize(){ g4NbzU[I
return pageSize; r0fEW9wL
} <ecif_a=m
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publicvoid setPageSize(int pageSize){ 1jkMje
this.pageSize = pageSize; 0PT\/imgN
} _'"$,~ZWY
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publicint getTotalCount(){ ;nZN}&m
return totalCount; 0zr Zrl
} (vb8Mk
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publicvoid setTotalCount(int totalCount){ OM 4,Sevk
if(totalCount > 0){ 4pC.mRu
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this.totalCount = totalCount; >Z&Y!w'A|u
int count = totalCount / *\T
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pageSize; #azD&6`
if(totalCount % pageSize > 0) -1 <*mbb0
count++; 6y}|IhX?z
indexes = newint[count]; 7<7
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for(int i = 0; i < count; i++){ ,/6 aA7(
indexes = pageSize * UCL aCt -
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} 3|9
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}else{ #0gwN2Nv"L
this.totalCount = 0; -3T~+
} Sz#dld Mz
} 7-`iI(N<
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publicint[] getIndexes(){ i!DO
return indexes; \aB>Q"pS
} :$?^ID
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publicvoid setIndexes(int[] indexes){ ZA
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this.indexes = indexes; /R!/)sg
} 3 F ke#t
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publicint getStartIndex(){ M qG`P
return startIndex; c037#&Q%#
} Ql.abU
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publicvoid setStartIndex(int startIndex){ M8}t`q[-&
if(totalCount <= 0) f_qW+fN::s
this.startIndex = 0; +`s%-}-r
elseif(startIndex >= totalCount) AV:P/M^B
this.startIndex = indexes 5\\a49k.p
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[indexes.length - 1]; mH\eJ
elseif(startIndex < 0) "JJEF2e@Z
this.startIndex = 0; eV)'@8p
else{ QM'Db`B
this.startIndex = indexes E0-<-w3'
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[startIndex / pageSize]; f%JC;Y
} K6X}d,g
} w] =q>p
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publicint getNextIndex(){ (M,IgSn9
int nextIndex = getStartIndex() + F|3iKK022
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pageSize; u[;,~eB%w
if(nextIndex >= totalCount) **!
return getStartIndex(); Gn7P` t*.
else 0}d^UGD
return nextIndex; =
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} xQK;3b
{
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publicint getPreviousIndex(){ @x@*=
int previousIndex = getStartIndex() - !.}ZlA
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pageSize; i9Tq h
if(previousIndex < 0) W`2Xn?g
return0; MzudCMF
else V.U9Q{y"
return previousIndex; rjLPX
} ;%_s4
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} P/hV{@x
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抽象业务类 U81--'@y
java代码: r(Vz(
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/** J jp)%c#_
* Created on 2005-7-12 yv2N5IQ>{V
*/ quGvq"Y>
package com.javaeye.common.business; ejjL>'G/|%
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import java.io.Serializable; |1[3RnGS
import java.util.List; UBZ37P
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import org.hibernate.Criteria; 6+s10?
import org.hibernate.HibernateException; wTw)GV4
import org.hibernate.Session; <*'%Xgm
import org.hibernate.criterion.DetachedCriteria; $wBF'|eU
import org.hibernate.criterion.Projections; znxP.=GB
import Ub_!~tb}?
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org.springframework.orm.hibernate3.HibernateCallback; !/;/ X\d
import 7u|X
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org.springframework.orm.hibernate3.support.HibernateDaoS h]{V/
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upport; i3[%]_eP.
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import com.javaeye.common.util.PaginationSupport; tW)KpX
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public abstract class AbstractManager extends :U!@
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HibernateDaoSupport { Q2(K+!Oe
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privateboolean cacheQueries = false; 6#SUfK;
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privateString queryCacheRegion; q<Sb>M/\,
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publicvoid setCacheQueries(boolean .%x%b6EI
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cacheQueries){ 2^;zj0]Rt
this.cacheQueries = cacheQueries; V }?MP-.c
} h%*@82DKK
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publicvoid setQueryCacheRegion(String XGCjB{IV
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queryCacheRegion){ 818,E
this.queryCacheRegion = RNMd,?dj
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queryCacheRegion; bMp[:dw`y
} i]
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publicvoid save(finalObject entity){ 5HqvSfq>?
getHibernateTemplate().save(entity); !CGpE=V
} hzcSKRm
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publicvoid persist(finalObject entity){ \)'5V!B|s
getHibernateTemplate().save(entity); [0M`uf/u
} oH]_2[
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publicvoid update(finalObject entity){ 5ca!JLs
getHibernateTemplate().update(entity); CAT{)*xc
} 5"WI^"6b:
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publicvoid delete(finalObject entity){ hC
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getHibernateTemplate().delete(entity); ,%X"Caz
} LuE0Hb"S8
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publicObject load(finalClass entity, qe<xH#6
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finalSerializable id){ &rbkw<=j
return getHibernateTemplate().load %5yP^BL0
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(entity, id); fG_<HJS(~
} ? l>Ra0
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publicObject get(finalClass entity, T jrz_o)
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finalSerializable id){ #6F|}E
return getHibernateTemplate().get |QHIB?C?`
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(entity, id); ?[#4WH-G
} 0 H0U%x8
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publicList findAll(finalClass entity){ '(fzznRH
return getHibernateTemplate().find("from "%rzL.</
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" + entity.getName()); 8I]rC<O6:
} VoC|z Rd_
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publicList findByNamedQuery(finalString U_C[9Z'P
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namedQuery){ H.]p\UY9
return getHibernateTemplate ,:6.Gi)|
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().findByNamedQuery(namedQuery); aHkt K/
} 9yYNX;C
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publicList findByNamedQuery(finalString query, qE*h UzA
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finalObject parameter){ 1deK}5'
return getHibernateTemplate %zYTTPLZ
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().findByNamedQuery(query, parameter); 5h[<!f=
} /:ju/~R}
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publicList findByNamedQuery(finalString query, 4K0Fc^-
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finalObject[] parameters){ ?`3G5at)9f
return getHibernateTemplate Q6$^lRNOpk
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().findByNamedQuery(query, parameters); ?.g="{5X
} RV>n Op}R
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publicList find(finalString query){ ow4|GLU^;
return getHibernateTemplate().find M Ui#3o\f
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(query); d;g]OeF
} S9E<)L
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publicList find(finalString query, finalObject |[iEi
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parameter){ xgJyG.?
return getHibernateTemplate().find p?#xd!tc2N
/ xb37,
(query, parameter); Eyh(257
} I|tn7|*-A[
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public PaginationSupport findPageByCriteria I3AxKA
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(final DetachedCriteria detachedCriteria){ p]Q(Z
return findPageByCriteria asJ t6C
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); f!bGH-.r5
} mMtva}=*
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public PaginationSupport findPageByCriteria ch)#NHZ9F
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(final DetachedCriteria detachedCriteria, finalint B&sa|'0U
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startIndex){ NC%)SG \
return findPageByCriteria OyATb{`'
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(detachedCriteria, PaginationSupport.PAGESIZE, rW[7
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startIndex); {W%/?d9m
} BFPy~5W
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public PaginationSupport findPageByCriteria S~\u]j^%y
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(final DetachedCriteria detachedCriteria, finalint zvKypx
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pageSize, mU;\,96#
finalint startIndex){ E@8<
return(PaginationSupport) 2l}3L
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getHibernateTemplate().execute(new HibernateCallback(){ $Hal]
publicObject doInHibernate 24I~{Qy
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(Session session)throws HibernateException { 18JAca8Zs
Criteria criteria = r(Y@;
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detachedCriteria.getExecutableCriteria(session); e[%g'}D:-
int totalCount = ktiC*|fd
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((Integer) criteria.setProjection(Projections.rowCount _j?/O)M
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()).uniqueResult()).intValue(); 6@J)kV
criteria.setProjection vLQh r&I
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(null); gro@+^DmT
List items = K2ry@haN
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criteria.setFirstResult(startIndex).setMaxResults -MItZ
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(pageSize).list(); "%)^:('Ki
PaginationSupport ps = vDVE#Nm_
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new PaginationSupport(items, totalCount, pageSize, LYp=o8JW|
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startIndex); ]`}R,'P
return ps; 3QD##Wr^
} $jNp-5+Q;
}, true); n##d!d|g
} |d=MX>i|G
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public List findAllByCriteria(final ~
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DetachedCriteria detachedCriteria){ ^6Y:9+
return(List) getHibernateTemplate '>"-e'1m(
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().execute(new HibernateCallback(){ m'ykDK\B
publicObject doInHibernate *m`KY)b=l
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(Session session)throws HibernateException { jl~?I*Gr
Criteria criteria = &ajpD sz;
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detachedCriteria.getExecutableCriteria(session); J(%kcueb
return criteria.list(); |T^c(RpOE
} *8j2iu-|
}, true); P]||Xbbp
}
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public int getCountByCriteria(final b+ J)
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DetachedCriteria detachedCriteria){ ]BBL=$*
Integer count = (Integer) 1U;p+k5c
pm}!?TL
getHibernateTemplate().execute(new HibernateCallback(){ j?'It`s
publicObject doInHibernate K(B|o6[
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(Session session)throws HibernateException { :,BKB*a\
Criteria criteria = l*z.20^P
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detachedCriteria.getExecutableCriteria(session); K\`>'C2_V
return J\x.:=V
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criteria.setProjection(Projections.rowCount I:G4i}mA
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()).uniqueResult(); 2q,> *B?
} #iAEcC0k5
}, true); Wf>scl`s
return count.intValue(); h$~\to$C
} ?\NWKp
} #Jqa_$\.
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用户在web层构造查询条件detachedCriteria,和可选的 #DFfySH)A
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /htM/pR
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PaginationSupport的实例ps。 CDTM<0`%
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ps.getItems()得到已分页好的结果集 8RJ^e[?o(
ps.getIndexes()得到分页索引的数组 NLA/XZ
ps.getTotalCount()得到总结果数 W6 U**ir.
ps.getStartIndex()当前分页索引 [:(^n0%
ps.getNextIndex()下一页索引 _M;M-hk/
ps.getPreviousIndex()上一页索引 Uc?#E $X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _wKaFf
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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 nVt,= ?_ U
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一下代码重构了。 ^*=.Vuqy
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我把原本我的做法也提供出来供大家讨论吧: 96FS-`
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首先,为了实现分页查询,我封装了一个Page类: [|!A3o
java代码: K7CrRT3>6
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/*Created on 2005-4-14*/ $+$S}i=
package org.flyware.util.page; ,=@%XMS
?|;q=p`t-
/** vRQ7=N{3
* @author Joa ',Q|g^rF]
* NP#:} )
*/ Z>si%Npm\
publicclass Page { O<o>/HH$
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/** imply if the page has previous page */ *lT: P-
privateboolean hasPrePage; FbWcq_
JgmX=6N
/** imply if the page has next page */ ~DYv6-p%
privateboolean hasNextPage; . h7`Q{
Z/f%$~Ch
/** the number of every page */ e
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privateint everyPage; aF41?.s
,p\:Z3{ZH
/** the total page number */ Adma~]T9
privateint totalPage; L"
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/** the number of current page */ k:qS'
privateint currentPage; G (o9*m1
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/** the begin index of the records by the current r$
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query */ ym=7EY?o
privateint beginIndex; -0>gq$/N=^
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/** The default constructor */ O;dtz\
public Page(){ 1R+/T
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} ?;0w 1
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/** construct the page by everyPage j
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* @param everyPage lIUaGz|
* */ 2]}4)_&d<e
public Page(int everyPage){ nign"r
this.everyPage = everyPage; H6t'V%Ys
} _* m<Z;Et
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/** The whole constructor */ =+z +`ot
public Page(boolean hasPrePage, boolean hasNextPage, NtfzAz/
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Id}/(Pkq
int everyPage, int totalPage, {gkzo3
int currentPage, int beginIndex){ rn9n _)
this.hasPrePage = hasPrePage; Oe~x,=X)
this.hasNextPage = hasNextPage; 9>6DA^
this.everyPage = everyPage; rV_i|
this.totalPage = totalPage; R9z:K_d,
this.currentPage = currentPage; 6Lb(oY}\3
this.beginIndex = beginIndex; ?XIB\7}
} 2Pm[
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/** }nUq=@ej
* @return SYE+A`a
* Returns the beginIndex. 2t[P-on
*/ A+w'quXn
publicint getBeginIndex(){ ki6Lt
return beginIndex; YEPQ/Pc
} zo|
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/** F(?O7z"d
* @param beginIndex TKe\Bi
* The beginIndex to set. D>fg
*/ [p+-]V
publicvoid setBeginIndex(int beginIndex){ C==yl"w
this.beginIndex = beginIndex; v8} vk]b
} .sCj3sX*
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/** \'Q rJ ?D
* @return CBr(a'3{Z
* Returns the currentPage. )UCc!
*/ OU
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publicint getCurrentPage(){ { MV,>T_
return currentPage; ?Qxf~,F
} FMi:2.E
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/** vR3\E"Zi
* @param currentPage f
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* The currentPage to set. IE|? &O
*/ 2O
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publicvoid setCurrentPage(int currentPage){ "vka7r
this.currentPage = currentPage; XkPE%m_5D
} = ;cTm5d;T
s(Bcw`'#
/** )Yu
* @return er8T:.Py
* Returns the everyPage. ;
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*/ SF=TG84<
publicint getEveryPage(){
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return everyPage; &,l(2z[
} 8c\\-{
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/** O
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* @param everyPage ]t0St~qUL)
* The everyPage to set. J%u,qF}h
*/ 'Qh1$X)R7a
publicvoid setEveryPage(int everyPage){ T-LX>*
this.everyPage = everyPage; j'k
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} jsFfrS"*
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/** L^jjf8_
* @return "Ccyj /
* Returns the hasNextPage. 16ZyLt
*/ `Gj(>z*
publicboolean getHasNextPage(){ dEZUK vo
return hasNextPage; g<N;31:c\
} ^)(-7H
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/** 0NeIQr1N_
* @param hasNextPage *`q?`#1&&.
* The hasNextPage to set.
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*/ Z]e`bfNnI
publicvoid setHasNextPage(boolean hasNextPage){ +Bf?3 5LP
this.hasNextPage = hasNextPage; s&hr$`V4
} lA pZC6Iwk
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/** ^Z-oO#)h#
* @return :r>^^tGT!
* Returns the hasPrePage. pM^Z C
*/ _6SAU8M,
publicboolean getHasPrePage(){ j4<K0-?
return hasPrePage; Xhq7)/jp
} NS65F7<&
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/** [#9i@40
* @param hasPrePage * bd3^mP
* The hasPrePage to set. ZfH+Iqd
*/ #R>x]Nt}
publicvoid setHasPrePage(boolean hasPrePage){ DXo]O}VF
this.hasPrePage = hasPrePage; S,j. ?u*!
} f S[-K?K
&s(J:P$!
/** =W &Mt
* @return Returns the totalPage. V2!0),]B
* -@e2/6Oi
*/ d[>HxPwo
publicint getTotalPage(){ [~u!*W
return totalPage; f4
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} zXM,cV/s
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/** ?!K6")SE
* @param totalPage 9b&|'BBW
* The totalPage to set. tYXE$i
*/ {l)$9!
publicvoid setTotalPage(int totalPage){ EJ>&\Iq
this.totalPage = totalPage; fZezDm(Q
} 6Cz
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} o K>(yC[
c:.~%AJx
^nK<t?KS
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 z)S6f79`Q
f"KrPx!^b
个PageUtil,负责对Page对象进行构造: \XPGA uEo
java代码: <^\rv42'(2
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Bb:C^CHIQm
/*Created on 2005-4-14*/ qa-FLUkIk!
package org.flyware.util.page; r=&,2meo
qXg&E}]:=
import org.apache.commons.logging.Log; h~m,0nGO
import org.apache.commons.logging.LogFactory; )Xh}N
J09jBQ]R
/** kDE-GX"Y
* @author Joa ~\mh\a&
* a3>/B$pE
*/ :{#O
publicclass PageUtil { odSPl{. >d
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privatestaticfinal Log logger = LogFactory.getLog >UMxlvTg&
4SZ,X^]I>
(PageUtil.class); 1vxRhS&FY
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/** Lxwi"ndP
* Use the origin page to create a new page |82q|@e
* @param page ly-(F2
* @param totalRecords W;'fAohr
* @return E?G'F3i
*/ J7* o%W*V
publicstatic Page createPage(Page page, int iCPm7AU
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totalRecords){ .P$m?p#
return createPage(page.getEveryPage(), ~<?Zj
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page.getCurrentPage(), totalRecords); @QQ%09*
} Qz,2PO
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/** :Ln)j%&
* the basic page utils not including exception |gA@WV-%
' @RF
handler y)fMVD"(
* @param everyPage /@F'f@;
* @param currentPage rXi&8R[
* @param totalRecords "esuLQC
* @return page J5G<Y*q
*/ '9zW#b
publicstatic Page createPage(int everyPage, int
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currentPage, int totalRecords){ PjeI&@
everyPage = getEveryPage(everyPage); |n/;x$Cb
currentPage = getCurrentPage(currentPage); E{<#h9=>
int beginIndex = getBeginIndex(everyPage, t,?,T~#9
q<
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currentPage); (dq_,LI
int totalPage = getTotalPage(everyPage, =/Gd<qz3
. vb##D
totalRecords); -N*[f9EJB
boolean hasNextPage = hasNextPage(currentPage, $6a9<&LP_
Gr\ ]6
totalPage); A?H#bRAs
boolean hasPrePage = hasPrePage(currentPage); 1zPS#K/3
8>9Mh!t}(I
returnnew Page(hasPrePage, hasNextPage, ]SCHni_
everyPage, totalPage, In1W/?
currentPage, ;OlnIxH(W
1'qXT{f/~
beginIndex); ~.:{
Ik]
} :C*}Yg
]E-/}Ysz
privatestaticint getEveryPage(int everyPage){ >qo!#vJc
a
return everyPage == 0 ? 10 : everyPage; ?6CLUu|7n
} w7Yu} JY^
KL'1)G"OH
privatestaticint getCurrentPage(int currentPage){ o8R_Ojh
return currentPage == 0 ? 1 : currentPage; itYoR-XJ
} Voo'ZeZa
a;xeHbE
privatestaticint getBeginIndex(int everyPage, int SZF 8InyF
^2~ZOP$A
currentPage){ pAOKy
return(currentPage - 1) * everyPage; YB"gLv?
} TcaW'&(K
6Qkjr</
privatestaticint getTotalPage(int everyPage, int ,`bW(V
},8|9z#pyB
totalRecords){ NftnbsTmy
int totalPage = 0; kG/1
<=NnrZOF
if(totalRecords % everyPage == 0) _d]{[&
p4t
totalPage = totalRecords / everyPage; .o/|]d`%
else 93]63NY
totalPage = totalRecords / everyPage + 1 ; 5-X$"Z|@
}|Qh+{H*.
return totalPage; 46=E- Tq
} rWTaCU^qV
\p(S4?I7
privatestaticboolean hasPrePage(int currentPage){ !, BJO3&
return currentPage == 1 ? false : true; nnyT,e%
} peVY2\1>R
oJTEN}fL
privatestaticboolean hasNextPage(int currentPage, Ak?9a_f
M2Nh3ijr
int totalPage){ KR( apO
return currentPage == totalPage || totalPage == PEI$1,z
{N2GRF~c-y
0 ? false : true; @@D/&}#F
} 9
Zo s;
ww{k_'RRJ
z:-{Y2F
} GJB+]b-
u&l;\w
CH4Nz'X2
6>WkisxG
jWUrw
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。 9K&$8aD
^UvL1+
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ~!({Unt+'
8WytvwB}
做法如下: 2U[/"JL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >)WE3PT/O"
u.2X"
的信息,和一个结果集List: Yb5U^OjyJ
java代码: e8`d<U
fz|*Plv
D9g*+KM&
/*Created on 2005-6-13*/ `:iMGqZN
package com.adt.bo; (csk
U<=TAWZ@
import java.util.List; gv eGBi
|B(,53
import org.flyware.util.page.Page; aG7Lm2{c"
Q,.dIPla
/** @wXYza0|d
* @author Joa ":eyf3M
*/ I;XM4a
publicclass Result { - k0a((?
D\G 8p;
private Page page; =_OJ
7K'
r3Ol?p
private List content; YHN6/k7H
f4S}Nga(
/** oT}$N_gFT
* The default constructor d[h=<?E5
*/ efyEzL
public Result(){ ;ab[YMkH
super(); 5i6Ji(
} )P7oL.)
#sU>L=
/** w?D=
* The constructor using fields A@3'I ;
* 'cCM[P+
* @param page ar@,SKU'K
* @param content Z84w9y7O<
*/ s1OSuSL>
public Result(Page page, List content){ ~Xx}:@Ld
this.page = page; S>5w=RK
this.content = content; ]fY:+Ru
} :LuA6
&v]xYb)+<
/** tuH#Cy
* @return Returns the content. g#P]72TQ
*/ R Q8"vF#
publicList getContent(){ x6aVNH=
return content; &LV'"2ng8
} Z&@P<
HE*^!2f
/** bv7)[,i
* @return Returns the page. V~Guw[RA
*/ Vb\^xdL>
public Page getPage(){ #pWy%U
return page; r6D3u(kMb
} |xb;#ruR6
:tENn
r.9v
/** ([m4dr
* @param content <OiH%:G/1
* The content to set. ke6,&s%{j
*/ 5aVZ"h"
public void setContent(List content){ {%2p(5FB
this.content = content; 5bZ0}^FYF
} JiqhCt\
rxxVLW
/** N/C$8D34
* @param page #x;d+Q@
* The page to set. mb'{@
*/ PY CG#U
publicvoid setPage(Page page){ <}^p5|
this.page = page; )1R[~]y
} D!,'}G#
} P/S ,dhs(
de8xl
>8NUji2I
S!-t{Q+j^
v?d`fd
2. 编写业务逻辑接口,并实现它(UserManager, 9QD+
p*jH5h cy
UserManagerImpl) ,*[N_[
java代码: ^K<!`B
fG?a"6~
lNe5{'OrO
/*Created on 2005-7-15*/ "Z';nmv'N
package com.adt.service; f. h3:_r
$U&p&pgH=W
import net.sf.hibernate.HibernateException; >z3l@
nr>Yj?la
import org.flyware.util.page.Page; 0#5&*
ZXj*Vu$_4
import com.adt.bo.Result; h5vetci/
6R2F,b(_
/** MO1H?Uhx
* @author Joa =BD|uIR
*/ =q[+e(,3
publicinterface UserManager { uC]c`Ue
eiA$) rzy
public Result listUser(Page page)throws ?`:+SncI"b
B%x?VOdBE
HibernateException; ,=pn}\R
fHuWBC_YO
} un`4q-S7
X~*/ ~f
iDCQqj`
zGL.+@
m8l!+8
java代码: Tv,ZS
v/7^v}[<
f DXTedrG/
/*Created on 2005-7-15*/ e ?Jgk$"
package com.adt.service.impl; yJw.z#bB#
sVlQ5M oo(
import java.util.List; #|V)>")
U$=Z`^<
import net.sf.hibernate.HibernateException; fn5!Nr ,
SJ,];mC0
import org.flyware.util.page.Page; D;:p6q}hT
import org.flyware.util.page.PageUtil; vgn,ZcX
z+c8G
import com.adt.bo.Result; "?_af
import com.adt.dao.UserDAO; ASSe;+yp
import com.adt.exception.ObjectNotFoundException; X=jD^"-
import com.adt.service.UserManager; ;wHyX)&X$
ey:%Zy
[~
/** K,bX<~e5
* @author Joa v# fny
*/ _GoFwVO
publicclass UserManagerImpl implements UserManager { T0o0_R
,{'ZP_
private UserDAO userDAO; ^C2SLLgeJ
QqC-ztz
/** R2Q1Rk#
* @param userDAO The userDAO to set. =QwT)KRB%
*/ dA#'HMh@
publicvoid setUserDAO(UserDAO userDAO){ Nc^:v/(P
this.userDAO = userDAO; }+:X= @Z@
} 7Zft]C?|@
*y~~~ 'J/
/* (non-Javadoc) e\ZV^h}TQ
* @see com.adt.service.UserManager#listUser gP!k[E,Q8
Gfepm$*%
(org.flyware.util.page.Page) bz`rSp8h
*/ H=XdgOui
public Result listUser(Page page)throws eV9,G8
0,cU^HMA
HibernateException, ObjectNotFoundException { B}I9+/|{
int totalRecords = userDAO.getUserCount(); d(vt0
if(totalRecords == 0) 9
H>JS
throw new ObjectNotFoundException Ih5CtcE1'd
CE4Kc33OU|
("userNotExist"); 1_mqPMm
page = PageUtil.createPage(page, totalRecords); 8%Ak
List users = userDAO.getUserByPage(page); |QyZ:`0u
returnnew Result(page, users); h.xtkD)Y~
} cf\GC2+"^$
-^>7\]
} _!yUr5&,Br
YCG$GD
7#PQ1UWl
d263#R
)SaMfP1=v
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #,SPV&
Jn\>Sz(96
询,接下来编写UserDAO的代码: N8*QAekN
3. UserDAO 和 UserDAOImpl: 1/=6s5vS}
java代码: qjN*oM,
0J.]`kR
|-]'~@~
/*Created on 2005-7-15*/ !3ji]q;uF
package com.adt.dao; c`UizZ
=_$Hn>vO
import java.util.List; 4@jX{{^6%
Upc_"mkI.
import org.flyware.util.page.Page; q3u:Tpn4%
k P=~L=cK
import net.sf.hibernate.HibernateException; `cFNO:
g9F?j
/** iG{xDj{CKv
* @author Joa 6^ ,;^
*/ FD8d-G
publicinterface UserDAO extends BaseDAO { gS!zaD7Nr
QRdh2YH`
publicList getUserByName(String name)throws P\$%p-G
X(;WY^i!
HibernateException; <@>l9_=R
}4q1"iMlO
publicint getUserCount()throws HibernateException; N3\vd_D(
T=[/x=
publicList getUserByPage(Page page)throws nz/cs n
nR,QqIFFw
HibernateException; S0lt_~
I$ ?.9&.&
} &Y2Dft_K
l-8rCaq&J
pE{Ecrc3|
B#o6UO\
$g
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java代码: V17!~
Eu[/* t+l
T@ zV
/*Created on 2005-7-15*/ iE^=Vf;
package com.adt.dao.impl; O0sLcuT$
vSwRj<|CF
import java.util.List; ;IR.6k$;
,b t
j6hg
import org.flyware.util.page.Page; rb]?"lizi
|}o3EX
import net.sf.hibernate.HibernateException; 2I_~]X53[
import net.sf.hibernate.Query; 3yLJWHO%W
U<6+2y P
import com.adt.dao.UserDAO; 9[:TWvd
ZDm Y${J
/** %0%Tp
* @author Joa se29IhS!e
*/ _W>xFBy
public class UserDAOImpl extends BaseDAOHibernateImpl HnKXO
QVkrhwp
implements UserDAO { e. R9:
ggy9euWV
/* (non-Javadoc) CsN^u H
* @see com.adt.dao.UserDAO#getUserByName cT
nC
V}Ce3wgvA
(java.lang.String) FQ u c}A
*/ eaDG7+iS
publicList getUserByName(String name)throws D=}\]Krmay
#j)"#1IE2W
HibernateException { BCh|^Pk
String querySentence = "FROM user in class ">vi=Tr
#GzowI'
com.adt.po.User WHERE user.name=:name"; OU<v9`<
Query query = getSession().createQuery H`rd bE
(btmg<WT"
(querySentence); H4<Q}([w
query.setParameter("name", name); V+t's*9o3
return query.list(); l\ VrD2j8
} 5 &0qr$
P[tYu:
/* (non-Javadoc) b8glZb*$
* @see com.adt.dao.UserDAO#getUserCount() gKtgW&PYm
*/ =X7_!vSv
publicint getUserCount()throws HibernateException { $ByP 9=|
int count = 0; a`>H69(bU
String querySentence = "SELECT count(*) FROM 0!M'z
-!
^D8^s
user in class com.adt.po.User"; z#2n+hwE
Query query = getSession().createQuery |^"0bu"
S:1g(f*85
(querySentence); ,(NN)Oj
count = ((Integer)query.iterate().next zpZfsn!
\} _,g
()).intValue(); -B?cF9
return count; aP#/%
} Q"H/RMo-
I:("f+
H
/* (non-Javadoc) J M`[|"R%
* @see com.adt.dao.UserDAO#getUserByPage tTWEhHQ`
`4g}(-
(org.flyware.util.page.Page) G=|~SYz
*/ oXUb_/
publicList getUserByPage(Page page)throws &^l(RBp]0
13+.>
HibernateException { ^!gq_x
String querySentence = "FROM user in class fElFyOo+
nkf7Fq}
com.adt.po.User"; 2+ywl}9
Query query = getSession().createQuery ?hViOh$.
lSc=c-iOv
(querySentence); W6B"QbHYz
query.setFirstResult(page.getBeginIndex()) ?$l|];m)-
.setMaxResults(page.getEveryPage()); Eihn%Esa
return query.list(); KD?b|y@
} bP> Kx-%q
tS-gaT`T
} 73Hm:"Eqd
Fu5c_"!
F<XOt3VY.
lc3Gu78 A/
M=3gV?N
至此,一个完整的分页程序完成。前台的只需要调用 m=SI *V
"lSh4X
userManager.listUser(page)即可得到一个Page对象和结果集对象 <y?=;54a
nv\K!wZI=b
的综合体,而传入的参数page对象则可以由前台传入,如果用 Qqs1%u;e8
h~ZLULW)B
webwork,甚至可以直接在配置文件中指定。 wE}Wh5
=[LorvX+
下面给出一个webwork调用示例: 216$,4i
java代码: [2h.5.af
MdmN7>
!#=3>\np+X
/*Created on 2005-6-17*/ P^tTg
package com.adt.action.user; (|NC xey
gd*2*o$g(
import java.util.List; :2K@{~8r
xF@&wg
import org.apache.commons.logging.Log; )]s<Czm%
import org.apache.commons.logging.LogFactory; 1GK>&;
import org.flyware.util.page.Page; 3&nN;4~Zx6
niKfat?
import com.adt.bo.Result; N$x&k$w R
import com.adt.service.UserService; kw
E2V+2
import com.opensymphony.xwork.Action; Ih>s2nL
)Yv=:+f
/** 5n{d jP
* @author Joa 3bYjW=_hA
*/ Ri~$hs!
publicclass ListUser implementsAction{ H2+b3y-1a]
?{e}ouKYX1
privatestaticfinal Log logger = LogFactory.getLog 5OzEY7K)
!&9(D^
(ListUser.class); `G_~zt/
:mW<
E
private UserService userService; bzxf*b1I
1m#.f=u{R
private Page page; P%gA`j
EO~L.E%W
privateList users; bwH[rT!n
WTJ{M$
/* p4*L}Q
* (non-Javadoc) *tgu@9b
* tW/g0lC%
* @see com.opensymphony.xwork.Action#execute() 8|)^m[c&
*/ g,rmGu3v
publicString execute()throwsException{ _DH^ K9,9
Result result = userService.listUser(page); gWzslgO6
page = result.getPage(); RB4 +"QUh
users = result.getContent(); q\~
#g.}
return SUCCESS; -z0;4O (K]
} G}9f/$'3
>6HGh#0(p
/** ;RRw-|/Wm
* @return Returns the page. p6R+t]oH
*/ mO;QT
public Page getPage(){ I<ohh`.
return page; %^L{K[}
} hlB\Xt
XUA@f*
/** [&PF ;)i
* @return Returns the users. 6Eu(C]nC(
*/ PXkpttIE]M
publicList getUsers(){ )Wr_*>xj
return users; (u} /(Ux
} ]i@73h YT
}`g-eF>p
/** DZtpY{=Z
* @param page >Vjn]V5y
* The page to set. !@F { FR
*/ YnRO>`
publicvoid setPage(Page page){ "`V@?+3
this.page = page; BB\GrD
} {0Y6jk>I
$_E.D>5^%7
/** k#Sr; "
* @param users &hI!mo
* The users to set. +tT"
*/ } &B6
publicvoid setUsers(List users){ W.MZN4=
this.users = users; e,/]]E/o
} ZK+F<}
jDpA>{O[
/** 94BH{9b5
* @param userService \&hq$
* The userService to set. z3K$gEve
*/ 3NLn}
publicvoid setUserService(UserService userService){ g"1V]
this.userService = userService; jts0ZFHc-
}
,"(G
} )>:~XA|?
A}(]J!rc
A-T-4I
_&hM6N
mi7?t/D1Z
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, u9OY
Jo
AX8~w(sv
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 6/mz.,g2
-je} PwT
么只需要: #0aBQ+_8H
java代码: `}l%61n0
;+E]F8G9r
'7sf)0\:<p
<?xml version="1.0"?> PJC(:R(j
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <-`.u`
,%*UF6B
M
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pqb'L]
Op ar+|p\
1.0.dtd"> k77 3h`;
ES&u*X:
<xwork> 7qB4_
1"ZtE\{
"
<package name="user" extends="webwork- .Rk8qRB
LBCH7@V1yR
interceptors"> >nghFm
9f( X7kt
<!-- The default interceptor stack name :}zyd;Rc
|NZi2Bu
--> @F<{/|P
<default-interceptor-ref Wn(!6yid
U]sAYp^$
name="myDefaultWebStack"/> SWV*w[X<X
U.Mfu9}#:
<action name="listUser" V2Vr7v=Y"
f[k#Znr
class="com.adt.action.user.ListUser"> iH }-
<param q5SPyfE[
*=!e,
name="page.everyPage">10</param> .P)lQk\
<result ~DInd-<5
1RYrUg"s"
name="success">/user/user_list.jsp</result> PR.3EL
</action> wc;n=
%
3}fOb
</package> +twoUn{#
Q6qW?*Y
</xwork> (4+P7Z,Nc
\sAaVdZJH(
'ztOl`I5V
lI=<lmM0|/
(SBhU:^h
90<g=B
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 {-\U)&6#v
)R JEOl1
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。 |:1{B1sqA
ukSv70Ev
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Jp=fLo 9
7Bp7d/R-
y!#-[K:
@(,1}3s
!{lH*
我写的一个用于分页的类,用了泛型了,hoho XDemdMy$
l*1|B3#m!
java代码: e3p|g]
T$%|=gq
p\w<~pN[
package com.intokr.util; 4nsJZo#S/
H$h#n~W~
import java.util.List; j<p.#jkT
I%3[aBz4
/** M|*YeVs9#
* 用于分页的类<br> XIdh9)]^}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 32YbBGDN!f
* ;o9h|LRs
* @version 0.01 dht0PZdx?
* @author cheng =u<:'\_
*/ dkC[SG`
public class Paginator<E> { [SPx
privateint count = 0; // 总记录数 MVYd\)\o
privateint p = 1; // 页编号 *LEy#N
privateint num = 20; // 每页的记录数 oACAC+CP
privateList<E> results = null; // 结果 Nc:s+ o
%!<Y
/** ;77K1
* 结果总数 |\,OlX,
*/ &xnQLz:#
publicint getCount(){ 3_
return count; S+T/(-W
} h aAY =:
')"+ a^c
publicvoid setCount(int count){ CvoFt=c$jE
this.count = count; npdljLN
} 928_e)V
U)J5K
/** '$9o(m#
* 本结果所在的页码,从1开始 YWFE*wQ!
* ^jL '*&l
* @return Returns the pageNo. R
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*/ $h#sb4ek
publicint getP(){ o`bc/3!
return p; uZ+bo&
} IzP,)!EE
:7v'[b
/** 'R7 \
* if(p<=0) p=1 V@
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* Cr.YSWg)4
* @param p (\AN0_
*/ --5F*a{R|
publicvoid setP(int p){ [l23b{
if(p <= 0) q(KjhM
p = 1; g>lZs
this.p = p; ]S6Gz/4aV+
} ?KC(WaGJQ
nKx)R^]k
/** Tuln#<:
* 每页记录数量 [9; @1I<x
*/ UqP{Cyy{
publicint getNum(){ ]\(8d[4
return num; {&51@UX
} /(dP)ysc
|mEWN/@C
/** GJ ^c^`
* if(num<1) num=1 ./YR8 #,
*/ }HgG<.H>
publicvoid setNum(int num){ @>2pY_
if(num < 1) QNNURf\[(
num = 1; 6nx\|F
this.num = num; Tgdy;?
} d][
Wm
y4^u&0}0$
/** G3.aw
* 获得总页数 `w@:h4f
*/ /"{d2
publicint getPageNum(){ rAenxZ,tF
return(count - 1) / num + 1; mWp>E`l
} 86ao{l6l C
.U1wVIM
/** \x<8
* 获得本页的开始编号,为 (p-1)*num+1 g) X3:=['
*/ /fI}QY1
publicint getStart(){ 1dH|/9
return(p - 1) * num + 1; ^? fOccfQ{
} uFkl^2
o@:"3s
/** - x
* @return Returns the results. 9[0iIT$q$
*/ v] m/$X2
publicList<E> getResults(){ <FT7QO$I
return results;
WTSh#L
} 2b"*~O;
qE)FQeN
public void setResults(List<E> results){ `^M]|7
this.results = results; IskL$Y ^
} \]X.f&u
l]*RiK2AC
public String toString(){ 1Bh"'9-!JT
StringBuilder buff = new StringBuilder HbTVuf o
OH`a3E{e
(); MxE]EJZ
buff.append("{"); `|t,Uc|7!
buff.append("count:").append(count); k&Pt\- 9on
buff.append(",p:").append(p); &YhAB\Rw
buff.append(",nump:").append(num); w~3X
m{
buff.append(",results:").append h@,ja
]J7qsMw
(results); =KE7NXu]-
buff.append("}"); SuE~Wb5&
return buff.toString(); "zEl2Xn28_
} 4Gu'WbJ
&[E\2 E
} u64#,mC[*
bC{4a_B
WtM%(8Y[]