Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [l44,!Z&
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3bYPi^
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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 lCafsIB
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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 h4p<n&)F
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。 )j,Y(V$P
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分页支持类: E' -lpE
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java代码: 0JT"Pv_
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package com.javaeye.common.util; Gh%R4)}
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import java.util.List; =csh=V@s
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publicclass PaginationSupport { :j2?v(jT_l
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publicfinalstaticint PAGESIZE = 30; =/5^/vwgY
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privateint pageSize = PAGESIZE; j(~e{HZ
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privateList items; &u`EYxT
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privateint totalCount; ,V^2Oa
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privateint[] indexes = newint[0]; "DO|B=EejP
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privateint startIndex = 0; ~=GwNo_
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public PaginationSupport(List items, int dNu?O>=
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totalCount){ 2dsXG$-W2
setPageSize(PAGESIZE); =jEVHIYt
setTotalCount(totalCount); 7D(Eo{ue
setItems(items); KvjsibI/Y
setStartIndex(0); S>Z07d6 &
} g^l~AR
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public PaginationSupport(List items, int o75l&`
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totalCount, int startIndex){ r01u3!
setPageSize(PAGESIZE); shgZru
setTotalCount(totalCount); ;
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setItems(items); A)#w~ X4
setStartIndex(startIndex); q nb#~=x^
} %W}YtDf\
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public PaginationSupport(List items, int 8]K+,0m6
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totalCount, int pageSize, int startIndex){ F MX^k
setPageSize(pageSize); ,ZI#p6
setTotalCount(totalCount); |A.nP9 hW
setItems(items); Sx:JuK@
setStartIndex(startIndex); S5BS![-QK
} dQn,0
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publicList getItems(){ IG.!M@_
return items; HTLS$o;Q
} .[r1Qz7G
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publicvoid setItems(List items){ +H:}1sT;n
this.items = items; l(Ya,/4
} (:P#l&f
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publicint getPageSize(){ }<qZXb1
return pageSize; CwM1
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} e:l7 w3?O
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publicvoid setPageSize(int pageSize){ C2CR#b=)i
this.pageSize = pageSize; {[4.<|26
} Up1n0
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publicint getTotalCount(){ 5g%D0_e5
return totalCount; y@@h )P#
} ( Sjlm^bca
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publicvoid setTotalCount(int totalCount){ "8p<NsU
if(totalCount > 0){ shD4";8*@
this.totalCount = totalCount; :q >)c]
int count = totalCount / Quwq_.DU
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pageSize; i#NtiZ.t=
if(totalCount % pageSize > 0) bE,#,
count++; :N!s@6
indexes = newint[count]; .,sbqL
for(int i = 0; i < count; i++){ O5MV&Zb(
indexes = pageSize * cQ;@z2\
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i; ]SAGh|+xl
} ;VzdlCZ@
}else{ m
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this.totalCount = 0; o5['5?i} /
} ;eJ|)*
} &_q8F,I \<
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publicint[] getIndexes(){ K5RgWP
return indexes; ]s0GAp"
} 194n
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publicvoid setIndexes(int[] indexes){ f%3MDI
this.indexes = indexes; /2''EF';
} SKF0p))BJ
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publicint getStartIndex(){ L=<$^ m
return startIndex; U'^ G-@
} ]XcWGQv~
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publicvoid setStartIndex(int startIndex){ ?\I@w4
if(totalCount <= 0) n{\d
this.startIndex = 0; *kTj,&x[
elseif(startIndex >= totalCount) s?"\+b
this.startIndex = indexes k0&FUO
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[indexes.length - 1]; fRxn,HyV
elseif(startIndex < 0) ~# \{'<
this.startIndex = 0; Ci 'V
else{ 7xM4=\~OG
this.startIndex = indexes :]4s;q:m
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[startIndex / pageSize]; ^F
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} \PD%=~
} ?VCp_Ji
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publicint getNextIndex(){ /eT9W[a
int nextIndex = getStartIndex() + ]heVR&bQ
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pageSize; qfdL *D
if(nextIndex >= totalCount) qo}yEl1
return getStartIndex(); PdEPDyFk h
else :fDzMD
return nextIndex; q6hH]Q>w*
} 0}YadNb7
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publicint getPreviousIndex(){ k{'<J(Hb
int previousIndex = getStartIndex() - OJ7Uh_;/
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pageSize; o6RT 4`
if(previousIndex < 0) d04gmc&*
return0; zJh!Q**
else $2Awp@j
return previousIndex; qW*k|;S
} QkWEVL@uM
q Y!LzKM0
} W4qnXD1n
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抽象业务类 lfG',hlI;
java代码: C^LxJG{L5
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/** >l=jJTJ;q
* Created on 2005-7-12 rLY I\
*/ I.Xbowl
package com.javaeye.common.business; C?MKbD=K
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import java.io.Serializable; v9!]/]U^
import java.util.List; *>!-t
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import org.hibernate.Criteria; J*zQ8\f=}
import org.hibernate.HibernateException; uhv_'Q
import org.hibernate.Session; Z"KrirZ
import org.hibernate.criterion.DetachedCriteria; :^qUr`)
import org.hibernate.criterion.Projections; VD $PoP
import %{UW!/
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org.springframework.orm.hibernate3.HibernateCallback; oLtzPC
import [S-#}C?~
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org.springframework.orm.hibernate3.support.HibernateDaoS 9xK#(M
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upport; WRRR "Q$
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import com.javaeye.common.util.PaginationSupport; D(&Zq7]n
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public abstract class AbstractManager extends 6-\'
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HibernateDaoSupport { ^jcVJpyT@R
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privateboolean cacheQueries = false; 4N1)+W8k*
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privateString queryCacheRegion; Ef@)y&hn
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publicvoid setCacheQueries(boolean ar S@l<79
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cacheQueries){ Bk@EQdn
this.cacheQueries = cacheQueries; :c Er{U8
} jwuSne
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publicvoid setQueryCacheRegion(String {%RwZ'
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queryCacheRegion){ }IdkXAB.
this.queryCacheRegion = * bhb=~
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queryCacheRegion; c>! ^\
} G)f!AuN=
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publicvoid save(finalObject entity){ rmFcSolt,f
getHibernateTemplate().save(entity); 0-uVmlk=/
} knfmJUT
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publicvoid persist(finalObject entity){ g&Uu~;jq]
getHibernateTemplate().save(entity); .eorwj]yb
} l>hvWK[ ?I
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publicvoid update(finalObject entity){ *.VNyay
getHibernateTemplate().update(entity); 2S4SG\
} `Tk~?aY
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publicvoid delete(finalObject entity){ dB QCr{7
getHibernateTemplate().delete(entity); DeeV;?:
} epG =)gd=8
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publicObject load(finalClass entity, +D[C.is>]}
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finalSerializable id){ T.B7QAI. H
return getHibernateTemplate().load wbk$(P'gN
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(entity, id); S)'&+HamI
} ELg$tc
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publicObject get(finalClass entity, ixoN#'y<"
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finalSerializable id){ 7j(gW
return getHibernateTemplate().get 8wEJyAu2
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(entity, id); bweAmSs
} Z Y5Pf
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publicList findAll(finalClass entity){ <^W5UU#Pg
return getHibernateTemplate().find("from ,% .)mf
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" + entity.getName()); ^X"x,8}&V
} t1$pl6&,
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publicList findByNamedQuery(finalString NSR][h_
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namedQuery){ +CXq41g"c
return getHibernateTemplate {d)L0KXK
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().findByNamedQuery(namedQuery); Hq?dqg' %~
} g:6`1C
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publicList findByNamedQuery(finalString query, u?>8`]r
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finalObject parameter){ 7xO~v23oe
return getHibernateTemplate )YZx]6\l)
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().findByNamedQuery(query, parameter); =rkW325O
} u_8Z^T
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publicList findByNamedQuery(finalString query, nyOmNvZf
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finalObject[] parameters){ (B?ZUXM,
return getHibernateTemplate m& D#5C
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().findByNamedQuery(query, parameters); Bo'v!bI7
} X+N8r^&
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publicList find(finalString query){ LW9F%?e!>
return getHibernateTemplate().find gkca{BJ
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(query); ]mC5Z6,1s
} WZP1g kX&M
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publicList find(finalString query, finalObject QNx xW2+
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parameter){ Ht]O:io`
return getHibernateTemplate().find 5v=e(Ph+
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(query, parameter); e nw*[D !
} g+(Y)9h&
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public PaginationSupport findPageByCriteria F%O+w;J4
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(final DetachedCriteria detachedCriteria){ mHH>qW{`
return findPageByCriteria Fr (;C>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); a(G}<
} YlR9
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public PaginationSupport findPageByCriteria 4[Wwm
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(final DetachedCriteria detachedCriteria, finalint sk3AwG;A
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startIndex){ #3A|Z=,5
return findPageByCriteria }'n]C| gZ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0Fsa&<{6?
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startIndex);
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} o,@(]e~
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public PaginationSupport findPageByCriteria aY6F4,7/B
*55unc
(final DetachedCriteria detachedCriteria, finalint n8`WU3&
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pageSize, J6<O|ng::
finalint startIndex){ /Ba/gq0j
return(PaginationSupport) vTIRydg2b
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getHibernateTemplate().execute(new HibernateCallback(){ 1jaK N*
publicObject doInHibernate EG3u)}vI
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(Session session)throws HibernateException { _1~pG)y$U
Criteria criteria = o%0To{MAF-
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detachedCriteria.getExecutableCriteria(session); wrsr U
int totalCount = JC;&]S.
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((Integer) criteria.setProjection(Projections.rowCount W! J@30
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()).uniqueResult()).intValue(); ,lFp4 C
criteria.setProjection -zI9E!24
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(null); tk>J
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List items = M|{NC`fa
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criteria.setFirstResult(startIndex).setMaxResults mU.c!|Y
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(pageSize).list(); b/
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PaginationSupport ps = rj4R/{h
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new PaginationSupport(items, totalCount, pageSize, ff~1>=^
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startIndex); \)ZCB7|
return ps; Z9Z\2t
} MIb[}w=
}, true); <d >!%
} QX-n l~
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public List findAllByCriteria(final ;V?d;O4u
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DetachedCriteria detachedCriteria){ _rmKvSD%
return(List) getHibernateTemplate <y&&{*KW8m
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().execute(new HibernateCallback(){ 8DM! ]L
publicObject doInHibernate ? nq%'<^^
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(Session session)throws HibernateException { )V&hS5P=S
Criteria criteria = Cl{Ar8d}
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detachedCriteria.getExecutableCriteria(session); aPQxpK?
return criteria.list(); g!9|1z
} l[rK)PM
}, true); I0!]J{
} $g/h=w@
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public int getCountByCriteria(final yrd1J$
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DetachedCriteria detachedCriteria){ <XN=v!2;
Integer count = (Integer) NCl@C$W9q
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getHibernateTemplate().execute(new HibernateCallback(){ 5}c8v2R:B
publicObject doInHibernate FZLx.3k4
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(Session session)throws HibernateException { ?Ygd|a5
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); vu#ZLq
return D3%2O`9
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criteria.setProjection(Projections.rowCount mrr~ #Bb>
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()).uniqueResult(); r4<aEj;l
} 0m"Ni:KEf
}, true); `#vbV/sM
return count.intValue();
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} {^1''
} AWKJ@&pA9m
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用户在web层构造查询条件detachedCriteria,和可选的 &b7_%,Bx4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 OA(.&5]
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PaginationSupport的实例ps。 D/GE-lq
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ps.getItems()得到已分页好的结果集 JodD6;P
ps.getIndexes()得到分页索引的数组 Ks@cwY
ps.getTotalCount()得到总结果数 N_Kdi%q
ps.getStartIndex()当前分页索引 Vzo<ma^
ps.getNextIndex()下一页索引 ;BYuNQr
ps.getPreviousIndex()上一页索引 I~&9c/&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 yMTO 5~U{
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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 Y]](.\ff
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一下代码重构了。 u6Lx3
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我把原本我的做法也提供出来供大家讨论吧: 4^M"V5tDx
9dBxCdpu
首先,为了实现分页查询,我封装了一个Page类: ,&qC
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java代码: eZN"t~\rX
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/*Created on 2005-4-14*/ ;i'[c`
package org.flyware.util.page; Z7RBJK7|.
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/** Y[dq"
* @author Joa %dv?n#Uf
* M
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*/ R&J?XQ
publicclass Page { }v4dOGc?
7B (%2
/** imply if the page has previous page */ x+pf@?w
privateboolean hasPrePage; K +3=gBU*w
Dfa3#{
/** imply if the page has next page */ ?%}!_F`h%
privateboolean hasNextPage; #/f~LTE
_#s,$K#
/** the number of every page */ 8/BMFRJ
privateint everyPage; pDSNI2
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/** the total page number */ \6JOBR
privateint totalPage; -!:5jfT"
#mA(x@:*
/** the number of current page */ OTdijQLY
privateint currentPage; {G VA4=UAE
s&(;
/** the begin index of the records by the current y,3ZdY"
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query */ JcA+ztPU
privateint beginIndex; F!wz{i6\h
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/** The default constructor */ =@?[.`
public Page(){ %&|
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} ,1$F#Eh
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/** construct the page by everyPage y{>f^S<
* @param everyPage ?!6Itkg
* */ @2)nhW/z6
public Page(int everyPage){ %dFJ'[jDL
this.everyPage = everyPage; Qop,~yK
} E<[
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/** The whole constructor */ *_o(~5w-K
public Page(boolean hasPrePage, boolean hasNextPage, kzDN(_<1
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int everyPage, int totalPage, %gh#gH
int currentPage, int beginIndex){ N}K
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this.hasPrePage = hasPrePage; ?YLq
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this.hasNextPage = hasNextPage; D5D *$IC
this.everyPage = everyPage; r~j
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this.totalPage = totalPage; DylO;+
this.currentPage = currentPage; C;N6",s!
this.beginIndex = beginIndex; YAOfuas]j
} jk03 Hd
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/** YcN|L&R.
* @return )ffaOS!\
* Returns the beginIndex. 7|DG1p9C
*/ v{VF>qEP
publicint getBeginIndex(){ og5VB
return beginIndex; )hXTgUZa
} Gl1XRNyC
*;Mi/^pzK
/** o8 JOpD
* @param beginIndex <$0is:]
* The beginIndex to set. 4a+gM._+O
*/ b-sN#'TDg
publicvoid setBeginIndex(int beginIndex){ Pwl*5/l
this.beginIndex = beginIndex; '|[V}K5m/f
} <m]0!ii
d-D,Gx]>$
/** yx :^*/
* @return fY[Fwjj3
* Returns the currentPage. 1^![8>u"
*/ ^w60AqR8
publicint getCurrentPage(){ HcsVq+
return currentPage; j|k/&q[St
} s)a-ky(
6]?mjG6
/** 3' i6<
* @param currentPage E1eGZ&&Gd
* The currentPage to set. wtY)(ka
*/ sFTAE1|
publicvoid setCurrentPage(int currentPage){ j Q5 F}
this.currentPage = currentPage; ayy\7b
} ?e$&=FC0;
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/** x#D%3v"l_*
* @return .B:ZyTI
* Returns the everyPage. K381B5_h
*/ -e/}DGL
publicint getEveryPage(){ !C#oZU]P
return everyPage; hG?y)g\A
} ]#)(D-i
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/** +'<PW+U$
* @param everyPage .gx^L=O:
* The everyPage to set. da7"Q{f+
*/ mqZH<.mn
publicvoid setEveryPage(int everyPage){ {aY) Qv}
this.everyPage = everyPage; l{{,D57J
} {dpC;jsW1
w}xA@JgQ%
/** @7twe;07r
* @return -tj#BEC[H(
* Returns the hasNextPage. k$3pmy*
*/ Z7a@$n3h
publicboolean getHasNextPage(){ >^s2$@J?p
return hasNextPage; _QL|pLf-
} u}@N
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/** ,8@<sFB'
* @param hasNextPage D&%8JL
* The hasNextPage to set. o08WC'bX
*/ |g&V? lI
publicvoid setHasNextPage(boolean hasNextPage){ ;llPM`)
this.hasNextPage = hasNextPage; J3eud}w
} 8;@y\0
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/** *7xcwjeP
* @return oy^-?+
* Returns the hasPrePage. $hhXsu=
*/ XV]N}~h o`
publicboolean getHasPrePage(){ sgfqIe1
return hasPrePage; %R0 Wq4}
} GW,EyOE+~
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id
/** {rc3`<%
* @param hasPrePage *D?=Ts
* The hasPrePage to set. hIe .Mv-I)
*/ .-Lrrk)R+
publicvoid setHasPrePage(boolean hasPrePage){ g0B] ;Y>(
this.hasPrePage = hasPrePage; s2O()u-
} ip-X r|Bq
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/** Nny*C`uDF
* @return Returns the totalPage. ;ElCWs->\
* W=+n|1
*/ hVzyvpw
publicint getTotalPage(){ @_ %RQO_X
return totalPage; cMY}Y
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} rN}pi@
&
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/** //63|;EEkl
* @param totalPage g04^M(
* The totalPage to set. (47?lw
&
*/ 4Zbn8GpC
publicvoid setTotalPage(int totalPage){ w}3N!jNDv
this.totalPage = totalPage; X
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} D6bYg `
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} 1#d2 +J*
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 dA)T>
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个PageUtil,负责对Page对象进行构造: #]}Ii{1?Y
java代码: L$PbC!1
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/*Created on 2005-4-14*/ 5A0]+)5E8
package org.flyware.util.page; j\ y!
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import org.apache.commons.logging.Log; _.s,gX
import org.apache.commons.logging.LogFactory; Qt.*Z;Gs
s5*4<VxQN.
/** spa:5]B
* @author Joa 6e ?xu8|
* ?|5M'o|9
*/ PPXwmR
publicclass PageUtil { 2.^{4 1:
DT]4C!dh
privatestaticfinal Log logger = LogFactory.getLog fI`Ez!w0
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(PageUtil.class); g{N}]_%Uh
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/** -}6ew@GE
* Use the origin page to create a new page IW\^-LI.
* @param page _[6sr7H!
* @param totalRecords @aS)=|Ls\
* @return 0F)v9EK(W4
*/ sC3Vj(d!i
publicstatic Page createPage(Page page, int fu!T4{2
cO5F=ZxR
totalRecords){ HyzSHI
return createPage(page.getEveryPage(), -Lq+FTezE
7i" b\{5
page.getCurrentPage(), totalRecords); %6Gg&Y$j!
} _HwA%=>7
c6:uM1V{
/** IHEbT
* the basic page utils not including exception XUP{]w`.Z
HT.,BF
handler =;Q/bD->
* @param everyPage $z$^
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* @param currentPage $@Vn+|
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* @param totalRecords yY8zTWji_
* @return page
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*/ KYiJXE[Q-
publicstatic Page createPage(int everyPage, int EDnNS
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currentPage, int totalRecords){ -E}X`?WhD
everyPage = getEveryPage(everyPage); V?EX`2S
currentPage = getCurrentPage(currentPage); mu\1hKq;B
int beginIndex = getBeginIndex(everyPage, f-M:ap(O
$OZ= L
currentPage); gAqK/9;
int totalPage = getTotalPage(everyPage, X.<3/
f"7MYw\
totalRecords); f\R_a/Us
boolean hasNextPage = hasNextPage(currentPage, PMsb"=Ds
!=YE hQ-
totalPage); #Vum
boolean hasPrePage = hasPrePage(currentPage); utmJ>GWSI
GFFwk4n1
returnnew Page(hasPrePage, hasNextPage, 7^i7U-A<A
everyPage, totalPage, 'HWl_M
currentPage, $NR[U+
xb\EJ1M>
beginIndex); 3wfcGQn|sD
} 6xDk3
1'f_C<.0
privatestaticint getEveryPage(int everyPage){ |:C0_`M9
return everyPage == 0 ? 10 : everyPage; s)WA9PiC
} 9n(68|^$
v?."`,e
privatestaticint getCurrentPage(int currentPage){ V0^{Ss1M
return currentPage == 0 ? 1 : currentPage; C+'-TLeu
} %Yu~56c-
(7qlp*8.s
privatestaticint getBeginIndex(int everyPage, int nXn@|J&z~U
3(oMASf
currentPage){ AFi_P\X
return(currentPage - 1) * everyPage; J$6WU z:?
} 1
*'
/B
g|Lbe4?
privatestaticint getTotalPage(int everyPage, int W.^zN' a
#ZJ 1\Ov
totalRecords){ >N#Nz
0|(
int totalPage = 0; {@2+oOuYfN
B .y}S
if(totalRecords % everyPage == 0) 6:(s8e
totalPage = totalRecords / everyPage; o9}\vN0F
else {}s/p9F4
totalPage = totalRecords / everyPage + 1 ; }.o.*N
AE:(:U\
return totalPage; iZG-ca
} g-K;J4 K%
cg {5\Vl
privatestaticboolean hasPrePage(int currentPage){ #TNjQNg@O
return currentPage == 1 ? false : true; T^4 dHG-(
} ;B@#,6t/
\:+\H0Bz
privatestaticboolean hasNextPage(int currentPage, :!_l@ =l
n#6{K6}k~
int totalPage){ PE5*]+lW.
return currentPage == totalPage || totalPage == .F,l>wUNe
zg ,=A?
0 ? false : true; "SN*hzs"]`
} AO8 #l
YP?
c>$d!IKCL
?1L<VL=b
} _GkLspSaU
7G+!9^
S*<J y(:n
ou-#+Sdd
,marNG
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。 ZP~H!
ZV--d'YiEm
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 sgOau\E
E#_/#J]UQn
做法如下: no8\Oees
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 bit|L7*14
/Pextj<
的信息,和一个结果集List: sl-wNIQ
java代码: ]r#b:W\
D9TjjA|zS
Ja~8ZrcY
/*Created on 2005-6-13*/ ;=n}61
package com.adt.bo; ho$}#o
HWV A5E[`Y
import java.util.List; ogIu\kiZ
EmaS/]X[
import org.flyware.util.page.Page; -r,v3n
[s$x"Ex
/** ?;oJ=.T
* @author Joa `xx.,;S
*/ pnuo;r s
publicclass Result { ~qZ6I)?
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,
private Page page; uD(C jHM>
.nZKy't
private List content; qRaPh:Q'
kxKb}>=
/** 2FZT
* The default constructor S!PG7hK2
*/ v@]SddP,?
public Result(){ Z-lhJ<0/Pa
super(); kcUn GiP
} k.b=EX|
9ye!kYF,
/** \FfqIc9;
* The constructor using fields qv(3qY
* d-b<_k{p
* @param page :@)R@. -
* @param content 2 T} >9X
*/ ~D@ YLW1z(
public Result(Page page, List content){ "8%$,rG1&
this.page = page; Zj -#"Gm
this.content = content; adu6`2*$
} gs!'*U)
oUn+tu:
/** w2xD1oK~o
* @return Returns the content. 5wW5
n5YS
*/ +%j27~R>D
publicList getContent(){ L{VnsY V
return content; 4L:O0Ggz}
} ~S<aIk0l
p@O Ip
/** omg#[
* @return Returns the page. Yr"Of*VNH
*/ &[{sA;
public Page getPage(){ >yKz8SV#
return page; QGI@5
} %0 {_b68x
x*:VE57,z
/** U]}F A2
* @param content eH7x>[lH.
* The content to set. KDb j
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*/ "Y^j=?1k
public void setContent(List content){ Zoxblk
this.content = content; eCR^$z=c
} r+m.!+
{St-
/** 9QX!HQ|5y8
* @param page [-[59H[6)
* The page to set. C)R hld
*/ y;CX)!8
publicvoid setPage(Page page){ pYzop4
this.page = page; dhA~Yu
} ML'y`S
} =PY{Elf
T16gq-h'
;_SSR8uHv
]e),#_M
"p3<-06
2. 编写业务逻辑接口,并实现它(UserManager, %y9sC1T
L7{}`O/g7
UserManagerImpl) 5qH*"i+|s
java代码: V*PL_|Q5
n%29WF6Zf
CR23$<FC
/*Created on 2005-7-15*/ c*7|>7C$i
package com.adt.service; G=[<KtWa
-a@e28Y
import net.sf.hibernate.HibernateException; 3QBzyJWf
,ja!OZ0$
import org.flyware.util.page.Page; RtR@wZ2\s
o}G`t
Bz
import com.adt.bo.Result; niCK(&z
2DPv7\fW
/** RHBQgD$
* @author Joa &-qQF`7
*/ >U`G3(#7S
publicinterface UserManager { aL[6}U0 (}
Y!oLNGY
public Result listUser(Page page)throws }\S'oC\[
zMA;1Na
HibernateException; [m{sl(Q
%m dtVQ@
} J;Z2<x/H
O<Q8%Az
&kzysv-_
66F?exr
5b/ ~]v
java代码: -t S\
:,JjN&
BVeMV4
/*Created on 2005-7-15*/ `dcz9 *
package com.adt.service.impl; }R16WY_'
;6``t+]q
import java.util.List; Z6${nUX
kd !?N
import net.sf.hibernate.HibernateException; 8cOft ;|qB
oDu6W9 +
import org.flyware.util.page.Page; %H\J@{f
import org.flyware.util.page.PageUtil; }NyQ<,+mq&
u$^tRz9
import com.adt.bo.Result; WN=0s
import com.adt.dao.UserDAO; 0D 2I)E72o
import com.adt.exception.ObjectNotFoundException; Dh8'og)7
import com.adt.service.UserManager; siI%6Gn;
`WXlq#:K
/** h-1?c\Qq:
* @author Joa =3(Auchl$Y
*/ F^bY]\-5
publicclass UserManagerImpl implements UserManager { {*B0lr`
s.bo;lk
private UserDAO userDAO; ?110} [jw
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/** K [DpH&
* @param userDAO The userDAO to set. t?G6|3
*/ 2lsUCQI;
publicvoid setUserDAO(UserDAO userDAO){ Sp X;nH-D
this.userDAO = userDAO; aA#79LS
} ~5&4s
1b1Ab
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/* (non-Javadoc) Q
>/,QX
* @see com.adt.service.UserManager#listUser seEo)m`d
T%) E!:}v
(org.flyware.util.page.Page) {>1FZsR49t
*/ ?v
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!
public Result listUser(Page page)throws ecs 0iW-,
+`GtZnt#
HibernateException, ObjectNotFoundException { ,9bnR;f\
int totalRecords = userDAO.getUserCount(); <EUR:
if(totalRecords == 0) u|t l@_
throw new ObjectNotFoundException 8-x-?7
L_Gw:"-+Q
("userNotExist"); z4SJxL
page = PageUtil.createPage(page, totalRecords); *p
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List users = userDAO.getUserByPage(page); /_l\7MeI
returnnew Result(page, users); BJUj#s0$
} K{ar)_V/
.c-a$39
} &$/
#"lW,V
To>,8E+GAb
nte?a e
K#Ck,Y"
HCN/|z1Xq
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *z VN6wG{
Ll|_Wd.K,
询,接下来编写UserDAO的代码: `?Q
p>t
3. UserDAO 和 UserDAOImpl: (|^m9v0:
java代码: QKj0~ia
5
HGGq;Nbm
`RnWh9
/*Created on 2005-7-15*/ 4c<
s"2F
package com.adt.dao; /dYv@OU?
p@G7}'|eyA
import java.util.List; nU_O|l9
pjFO0h_Y
import org.flyware.util.page.Page; vv
,4n&D
VQla.Y
import net.sf.hibernate.HibernateException; aL;!BlU8v
mcez3gH
/** JaY"Wfc
* @author Joa 12n:)yQy
*/ &Pr\n&9A
publicinterface UserDAO extends BaseDAO { Zigv;}#
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publicList getUserByName(String name)throws 2DW@}[G
v3-'
GgM
HibernateException; E7A!,A&>
m]2xOR_
publicint getUserCount()throws HibernateException; {=[>N>"
3^y(@XFt
publicList getUserByPage(Page page)throws z lr!
k3#'g'>yh
HibernateException; 0ae8Xm3J@R
f(5(V
%
} p +i1sY
W91yj:
5X!-Hj
1/Ts .\K3
rz "$zc.)
java代码: 5YD~l(,S1]
+Dy^4p?o
NGc~%0n
/*Created on 2005-7-15*/ Z[. M>|
package com.adt.dao.impl; o&q>[c
E]`7_dG+T
import java.util.List; uNzc,OH
p:4jY|q
import org.flyware.util.page.Page; h+[6i{
O_:l;D#i
import net.sf.hibernate.HibernateException; _nbr%PD,
import net.sf.hibernate.Query; X 0y$xC|<
T^}UE<
import com.adt.dao.UserDAO; sW[-qPK<
jfuHZ^ YA
/** qE~_}4\Z9
* @author Joa y+(\:;y$7
*/ k]@]a
public class UserDAOImpl extends BaseDAOHibernateImpl A;TP~xq\
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aa
implements UserDAO { [r/zBF-.
&P?2H66s
/* (non-Javadoc) j<<d A[X
* @see com.adt.dao.UserDAO#getUserByName FO2e7p^Q
PE%$g\#?
(java.lang.String) 1)(>'pY
*/ -* ,CMw
publicList getUserByName(String name)throws $O%{l.-O
nYyhQX~]B
HibernateException { rpT.n-H>%A
String querySentence = "FROM user in class L80(9Y^xn
~Bzzu %S
com.adt.po.User WHERE user.name=:name"; bKo %Ak,
Query query = getSession().createQuery 8 t5kou]h
11=$]K>
(querySentence); 'X?xn@?
query.setParameter("name", name); jo`ZuN{
return query.list(); $m 4-^=
} x)::^'74
g@`i7qN
/* (non-Javadoc) c5YPV"X
* @see com.adt.dao.UserDAO#getUserCount() iQ)ydY a
*/ W7>2&$
publicint getUserCount()throws HibernateException { +<7Oj s>o
int count = 0; >d/H4;8
String querySentence = "SELECT count(*) FROM Gnkar[oa&
OR<+y~Rv
user in class com.adt.po.User"; (@1:1K(
Query query = getSession().createQuery 6CY&pbR
%=aKW[uq]
(querySentence); _[2@2q0
count = ((Integer)query.iterate().next S&-K!XyJ
x;/LOa{LR
()).intValue(); ?E([Nc0T
return count; B
71/nt9
} @]@|H?
_wq?Pa<)e
/* (non-Javadoc) " 9Gn/-V>
* @see com.adt.dao.UserDAO#getUserByPage <S@jf4
%**f`L%jN
(org.flyware.util.page.Page) O`5,L[i1y
*/ Gt`7i(
publicList getUserByPage(Page page)throws ?{ir$M
4%(Ji
HibernateException { 6}4})B2
String querySentence = "FROM user in class DP ? dC`
pO`KtagL
com.adt.po.User"; P49\A^5S!
Query query = getSession().createQuery @+u>rS|IB
d ]P~
(querySentence); &k}f"TX2
query.setFirstResult(page.getBeginIndex()) "s+4!, k
.setMaxResults(page.getEveryPage()); r"7n2
return query.list(); ;P@]7vkff
} b9.M'P\
5~*)3z^V
} pCIzpEsRs
%$!3Pbui
ag=d6q
Rr)+M3'
Jz@~$L
至此,一个完整的分页程序完成。前台的只需要调用 ?8b19DMK6
!|cg=
userManager.listUser(page)即可得到一个Page对象和结果集对象 GtA`0B
P?54"$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 +EETo):
FcDS*ZEk!
webwork,甚至可以直接在配置文件中指定。 4.RQ3SoDa
zKJ2~=
下面给出一个webwork调用示例: BrV{X&>[i
java代码: Z~5) )5Ye;
xUo6~9s7
k:@DK9
"^
/*Created on 2005-6-17*/ +a1x;
package com.adt.action.user; #~ u0R>=
LFp "Waiv
import java.util.List; +{J8,^z#
F@w; .e!
import org.apache.commons.logging.Log; NTg@UT<
import org.apache.commons.logging.LogFactory; IrLGAQ0
import org.flyware.util.page.Page; qL(Q1O!
}r:o8+4
import com.adt.bo.Result; zZ5:)YiW-
import com.adt.service.UserService; ep0,4!#FAO
import com.opensymphony.xwork.Action; !IxO''4
S{@}ECla
/** [|}IS@
* @author Joa C*7/iRe
*/ {z#2gc'Q
publicclass ListUser implementsAction{ #/)t]&n
"}4%v Zz
privatestaticfinal Log logger = LogFactory.getLog 1yy?1&88S
i|YS>Pw~j
(ListUser.class); mgs(n5V5
a?cJl
private UserService userService; s{hKl0ds
UO/sv2CN
private Page page; :+rGBkw1m
7s9h:/Lu
privateList users; wj|Zn+{"nF
,"(L2+Yp
/* ]Bw0Qq F#
* (non-Javadoc) sDY~jP[Oa
* IK~&`n](>
* @see com.opensymphony.xwork.Action#execute() [6/QUD8
*/ 0XHQ5+"8
publicString execute()throwsException{ M6Fo.eeK3
Result result = userService.listUser(page); Q?{%c[s
page = result.getPage(); XYE|=Tr]
users = result.getContent(); x0*{oP
return SUCCESS; j0jl$^
} q'2vE;z Kb
EE/mxN(<
/** 3a/n/_D
* @return Returns the page. Y.tx$%
*/ 4w4B\Na>l
public Page getPage(){ l'@-?p(Vuw
return page; VJh8`PVX
} SC{m@
1J@Iekat
/** .R9Z$Kbq
* @return Returns the users. H=t"qEp
*/ ]S|FK>U[
publicList getUsers(){ Xlo7enzY
return users; wb-yAQ8
} 7*/{m K)
5=dL`
/** B@,9Cx564
* @param page k$EVr([
* The page to set. K|& f5w
*/ zmMc*|
publicvoid setPage(Page page){ /r}L_wI
this.page = page; a QH6akH
} Fe+
@;
M[uWX=
/** z\YIwrq3*
* @param users +^)v"@,VP
* The users to set. oFY!NMq}:
*/ ON ?Y
Df
publicvoid setUsers(List users){ D$>_W ,*V
this.users = users; ,pNx(a
} c/{FDN
>.h:Y5
/** ,Z.sGv
* @param userService 4
1_gak;
* The userService to set. *O?c~UJhhV
*/ _n&Nw7d2
M
publicvoid setUserService(UserService userService){ ngY%T5-
this.userService = userService; (FuIOR
} UZZJtQt
} 9KSi-2?H
_IH" SVub
g 7oY 1;
%H{p&ms
|HazM9=
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, xO$P
C,
@hLkU4S
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 Cs $5Of(
cby#
么只需要: qnm_#!&uHT
java代码: (8 nv&|
S_}`'Z )
#-hO\
QdC
<?xml version="1.0"?> *kr/,_K
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >rG>Bz^Pu
Io6/Fv>!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- yNu_>!Cp5
{.Tx70kn
1.0.dtd"> ^l &lwSRVt
6(
HF)z
<xwork> [P$Xr6#
UA[`{rf
<package name="user" extends="webwork- %>_[b,
GAGS-G#
interceptors"> f^c+M~\JKj
qsj{0 Go
<!-- The default interceptor stack name p [ O6
!iXRt" )
--> <,d550GSm
<default-interceptor-ref .Po"qoGy
_vQ52H,
name="myDefaultWebStack"/> XTol|a=
L"_XWno
<action name="listUser" J0G@]H
"> uN={Iy
class="com.adt.action.user.ListUser"> Aoa8Q
E
<param H`EhsYYK
gY}In+S
name="page.everyPage">10</param> gesbt
<result :Mx
_0/unJl`
name="success">/user/user_list.jsp</result> Dc9uq5l
</action> k.@![w\ea
Z9{~t
</package> Hq@+m!
Daf|.5>(@
</xwork> :uL<UD,vu3
;m/e|_4;y
nF3}wCe)
&|>@K#V8-;
&(F
c .3m
9u=A:n\
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 4;`z6\u9-
~/OY1~c
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。 w$2q00R>
'g v0;L
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .ZXoRT
1 $E(8"l
vEv kC
m*0YMS>Y |
7vRtTP
我写的一个用于分页的类,用了泛型了,hoho bzN[*X|
5#Er& 6s
java代码: @!ChPl
c-Gp|.C
.qBc;u
package com.intokr.util; xJq|,":gj
8NN+Z<
import java.util.List; [lmF2
&AiAd6
/**
js$R^P
* 用于分页的类<br> (qn=BPI
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~(kEGEF
* osV6=
* @version 0.01 J,W<ha*
* @author cheng +{UY9_~\3
*/ "ubp`7%67
public class Paginator<E> { #~0Nk6*u
privateint count = 0; // 总记录数 J}|X
privateint p = 1; // 页编号 \C~X_/sg
privateint num = 20; // 每页的记录数 CS^6$VL7e
privateList<E> results = null; // 结果 OVK
)]- ~
84ij4ZYe
/** tBo\R?YRs
* 结果总数 1M ?BSH{
*/ -cqE^qAdX
publicint getCount(){ z?/_b
return count; K3&xe(
} x}G:n[B7_V
Hv6h7-
publicvoid setCount(int count){ osC?2.
this.count = count; .7iRV
} i_qY=*a?y
\w9}O2lL
/** WfPb7T
* 本结果所在的页码,从1开始 =m.Nm -g
* >$Y/B=e
* @return Returns the pageNo. ;zCUx*{
*/ VcjbRpTy&
publicint getP(){ Q14zc0N
return p; ay"jWL-
} k1&9 bgI
`46~j
/** g`fG84
* if(p<=0) p=1 *s6x
* zs$r>rlO
* @param p G
e;67
*/ }'[>~&/"
publicvoid setP(int p){ 7QO/; zL
if(p <= 0) Gp%po@A&
p = 1; _^ hg7&dF
this.p = p; *'@Oo
} *85N_+Wv!
z/t|'8f
/** <2U#U;
* 每页记录数量 ;m7V]h? R
*/ .Fb#j+Lq
publicint getNum(){ J 8i;E4R
return num; ZTmy} @l
} s'HsLe0|
@9/I^Zk
/** PV68d; $:8
* if(num<1) num=1 ki1(b]rf
*/ x0 j5D
publicvoid setNum(int num){ P&`%VW3E
if(num < 1) N'{[BA(eE
num = 1; Ejug2q
this.num = num; x*OdMr\n8?
} Eq-+g1a
<':h/d
/** }`R,C~-|^
* 获得总页数 }:8}i;#M
*/ U>tR :)
publicint getPageNum(){ $;v! ,>
return(count - 1) / num + 1; ?(ORk|)kU
} w8lrpbLh
zx@!8Z
/** <Gpji5f2
* 获得本页的开始编号,为 (p-1)*num+1 $dfc@Fn^x
*/ T//xxH]w-
publicint getStart(){ kn3w6]
return(p - 1) * num + 1; s8-RXEPb
} M0
z%<_<}
*aErwGLB8
/** .W]k8N E
* @return Returns the results. l!ow\ZuQBF
*/ ]V"P
&;m
publicList<E> getResults(){ l7`{ O/hN
return results; &'6/H/J
} HZ3;2k
[>ghs_?dZ
public void setResults(List<E> results){ 77\+V 0cF
this.results = results; u\LNJo| B
} 1$Hou
Q4XlYgIV2A
public String toString(){ BTAbDyH5
StringBuilder buff = new StringBuilder k>&cHCS`*
=.`\V]
(); 7@@g|l]
buff.append("{"); RV~t%Sw^
buff.append("count:").append(count); m6R/,
buff.append(",p:").append(p); z;JV3)E
buff.append(",nump:").append(num); ^E}?YgNp
buff.append(",results:").append h,/Aq
)kep:-wm
(results); ^ZMbJe%L
buff.append("}"); 're:_;lG
return buff.toString(); FJn-cR.n
} o~$O$
Bx45yaT
} A]c'TT@6
bM?gAY]mB8
&S4*x|-C&