Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1bZiPG{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]Y&)98
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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 !u{"] T:
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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 ;c-
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分页支持类: prEu9$:t
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java代码: V9j1j}
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package com.javaeye.common.util; 04PoBv~g
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import java.util.List; mzE$aFu8
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publicclass PaginationSupport { pl x/}ah8
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; d&T6p&V$
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privateList items; +'['HQ)
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privateint totalCount; 9;]wF8h
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privateint[] indexes = newint[0]; .D,?u"fk|
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privateint startIndex = 0; 0^}'+t,lc
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public PaginationSupport(List items, int U8K&Q4^
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totalCount){ Y$x"4=~
setPageSize(PAGESIZE); D#d8 ^U
setTotalCount(totalCount); 4aN+}TkH@G
setItems(items); eMN+qkvH
setStartIndex(0); chO'Q+pw
} EItxRHV5
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public PaginationSupport(List items, int *f `s%&Y]s
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totalCount, int startIndex){ ..jq[(;N
setPageSize(PAGESIZE); ?-8y4
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setTotalCount(totalCount); rT f lk
setItems(items);
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setStartIndex(startIndex); tg7C;rJ
} p*pn@z
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public PaginationSupport(List items, int !K3i-zY
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totalCount, int pageSize, int startIndex){ uX<+hG.n}
setPageSize(pageSize); wTTTrk
setTotalCount(totalCount); iN<(O7B;
setItems(items); G-\<5]k]
setStartIndex(startIndex); [i(Cl}
} pXPqDA
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publicList getItems(){ S}.\v<
return items; 0
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} 2q"_^deI5*
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publicvoid setItems(List items){ <#xrrRhm}
this.items = items; Job/@> ;
} M8 iEVJ
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publicint getPageSize(){ >"cr-LB
return pageSize; s.^c..e75C
} nU}~I)@V
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publicvoid setPageSize(int pageSize){ /:#j?c
this.pageSize = pageSize; <K.Bq]
} I:F'S#
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publicint getTotalCount(){ _qY`KP"
return totalCount; R(: 4s
} [urH a
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publicvoid setTotalCount(int totalCount){ RI(=HzB
if(totalCount > 0){ "0|BoG
this.totalCount = totalCount; u=vh
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int count = totalCount / `6rrXU6|
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pageSize; TkA9tFi
if(totalCount % pageSize > 0) \4OK!6LkI
count++; B^Xy0fq
indexes = newint[count]; {hxW,mmA
for(int i = 0; i < count; i++){ M} O[`Fx{W
indexes = pageSize * s,84*6u
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} d2ohW|
}else{ Tv`_n2J`2
this.totalCount = 0; kfVZ=`p}
}
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} 7.%f01/i
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publicint[] getIndexes(){
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return indexes; PM@XtL7J
} %njOX#.w
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publicvoid setIndexes(int[] indexes){ l#Yx
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this.indexes = indexes; JdtPY~k0
} VR"8Di&)
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publicint getStartIndex(){ L5/mO6;k
return startIndex; BjYOfu'~z
} 0X.TF
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publicvoid setStartIndex(int startIndex){ 0"TgLd
if(totalCount <= 0) fc3 Fi'^
this.startIndex = 0; NP "ylMr7P
elseif(startIndex >= totalCount) 6?O}Q7G
this.startIndex = indexes L4~
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[indexes.length - 1]; 'X54dXS?l
elseif(startIndex < 0) }0Y`|H\v
this.startIndex = 0; NJ<N %hcjK
else{ `y'aH
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this.startIndex = indexes ):S!Nl
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[startIndex / pageSize]; MZ)T0|S_
} AhR0zg
} E&'#=K[
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publicint getNextIndex(){ \Y9I~8\gB
int nextIndex = getStartIndex() + vuZf#\zh}
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pageSize; mzu<C)9d,
if(nextIndex >= totalCount) z<t>hzl7
return getStartIndex(); <E SvvTf
else U3/8A:$y
return nextIndex; mdaYYD=c%
} # J]~
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publicint getPreviousIndex(){ Jns/v6
int previousIndex = getStartIndex() - cg{Gc]'1#
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pageSize; [NL -!
if(previousIndex < 0) ]9s\_A9
return0; };^}2Xo+
else g**5z'7
return previousIndex; !x8kB
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} &5d\~{;
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} w]}f6VlEl
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抽象业务类 1 )'Iu`k/
java代码: [EER4@_
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/** %P;[fJ
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* Created on 2005-7-12 QAi1,+y]7w
*/ u3ST;
package com.javaeye.common.business; L@?e:*h
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import java.io.Serializable; }Bi@?Sb
import java.util.List; &1l~&,,
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import org.hibernate.Criteria; zC#%6@P\
import org.hibernate.HibernateException; a(f(R&-:$Y
import org.hibernate.Session; 5/,Qz>QE[
import org.hibernate.criterion.DetachedCriteria; &y\igX1
import org.hibernate.criterion.Projections; M|H2kvl
import Y0}4WWV
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org.springframework.orm.hibernate3.HibernateCallback; 2qjyFTT
import 8+ hhdy*b
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org.springframework.orm.hibernate3.support.HibernateDaoS 5e8xKL
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upport; KGD'mByt"
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import com.javaeye.common.util.PaginationSupport; mqw 84u
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public abstract class AbstractManager extends zIm-X,~I$
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HibernateDaoSupport { 5VZjDg?
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privateboolean cacheQueries = false; w&5/Zh[~~L
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privateString queryCacheRegion; "[.ne)/MC
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publicvoid setCacheQueries(boolean Mt=R*M}D0
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cacheQueries){ c$A@T~$
this.cacheQueries = cacheQueries; -"tY{}z
} kT2Wm/L
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publicvoid setQueryCacheRegion(String WN\PX!K9
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queryCacheRegion){ #D0 ~{H
this.queryCacheRegion = g>T
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queryCacheRegion; JnHNkCaU
} NNp}|a9
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publicvoid save(finalObject entity){ 5k~\or 5_
getHibernateTemplate().save(entity); m9!DOL1pl
} A_F0\ EN*
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publicvoid persist(finalObject entity){ N<n8'XDdG
getHibernateTemplate().save(entity); bw5T2wYZ
} |]tZ hI"3<
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publicvoid update(finalObject entity){ I=odMw7Hj
getHibernateTemplate().update(entity); $L\@da?
} AqqHD=Yp
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publicvoid delete(finalObject entity){ w5(yCyNp~
getHibernateTemplate().delete(entity); =x#&\ui
} .<.#aY;N
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publicObject load(finalClass entity, WGMb8 /{$P
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finalSerializable id){ u>}zm_
return getHibernateTemplate().load ,Z5Fea
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(entity, id); Fs)
} y!hi"!
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publicObject get(finalClass entity, ~#4~_d.=L
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finalSerializable id){ Y;g% e3nu
return getHibernateTemplate().get }Aw47;5q;
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(entity, id); 7H#2WFQ7
} 0ERsMnU'
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publicList findAll(finalClass entity){ hLo>R'@uN
return getHibernateTemplate().find("from 8JP6M!F#
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" + entity.getName()); lvPpCAXY
} ;AJ<
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publicList findByNamedQuery(finalString T5q-"W6\
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namedQuery){
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return getHibernateTemplate #h{Nz/h+
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().findByNamedQuery(namedQuery); P=Puaz5&{
} Q.1XP
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publicList findByNamedQuery(finalString query, 1w17L]4
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finalObject parameter){ Bz:&f46{
return getHibernateTemplate %",ULtZ+
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().findByNamedQuery(query, parameter); bM5CDzH(#X
} lz}llLb1
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publicList findByNamedQuery(finalString query, !-ZP*V3}h
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finalObject[] parameters){ *_#&"(P
return getHibernateTemplate zWtj|%ts
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().findByNamedQuery(query, parameters); .aJ%am/:%
} 7jT#BWt
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publicList find(finalString query){ {KsVK4\r
return getHibernateTemplate().find QY6O(=
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(query); 8F)=n \
} CC>($k"
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publicList find(finalString query, finalObject CWBbSGk
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parameter){ {Hr>X
return getHibernateTemplate().find FCAJavOGH
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(query, parameter); U1jSUkqb
} @2?=3Wf
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public PaginationSupport findPageByCriteria PF`:1;PU
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(final DetachedCriteria detachedCriteria){ A(NEWO
return findPageByCriteria O/$ v69:
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); DP0Z*8Ia
} GBW 7Y
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public PaginationSupport findPageByCriteria 'f8
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(final DetachedCriteria detachedCriteria, finalint .01TTK *
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startIndex){ 6# R;HbkO
return findPageByCriteria :/~_sJt C
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(detachedCriteria, PaginationSupport.PAGESIZE, v|>BDN@,6
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startIndex); =uS8>.Qj
} D"'#one
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public PaginationSupport findPageByCriteria 7F~xq#Wi#
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(final DetachedCriteria detachedCriteria, finalint jWhD5k@v
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pageSize, sE}sE=\
finalint startIndex){ <9T
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return(PaginationSupport) h ;jsH!
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getHibernateTemplate().execute(new HibernateCallback(){ F\:{}782u
publicObject doInHibernate u>1v~3,r#
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(Session session)throws HibernateException { 0oQ/J:
Criteria criteria = f}A^]6MO:
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detachedCriteria.getExecutableCriteria(session); %$^$'6\77
int totalCount = >[hrJn[
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((Integer) criteria.setProjection(Projections.rowCount D8W(CE^}
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()).uniqueResult()).intValue(); u"eZa!#
criteria.setProjection ddl3fl#f
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(null); 5t TLMZ `o
List items = j_hjCQ
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criteria.setFirstResult(startIndex).setMaxResults - f+CyhR"*
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(pageSize).list(); (]oFB$
PaginationSupport ps = Af$0 o=".
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new PaginationSupport(items, totalCount, pageSize, !P+~c0DF
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startIndex); 8}]l9"q(
return ps; 3huzz<n3
} CRP7U
}, true); ">03~:oA
} iFY]0@yt
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public List findAllByCriteria(final (gFQK[
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DetachedCriteria detachedCriteria){ &0?DL
return(List) getHibernateTemplate H;4oZ[g
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().execute(new HibernateCallback(){ [<,0A]m
publicObject doInHibernate Uzy;#q
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(Session session)throws HibernateException { lrM.RM96
Criteria criteria = \z<ws&z3`$
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detachedCriteria.getExecutableCriteria(session); MAl{66
return criteria.list(); 3ZLr"O1l )
} DX7Ou%P,mg
}, true); 8s\8`2=
} K#%O3RRs
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public int getCountByCriteria(final o<9yaQ;
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DetachedCriteria detachedCriteria){ 2&3eAJC
Integer count = (Integer) yOn H&Jj
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getHibernateTemplate().execute(new HibernateCallback(){ bf&.rJ0
publicObject doInHibernate 7/$nA<qM
vy>];!Cu
(Session session)throws HibernateException { 30wYc &H
Criteria criteria = o;Hd W
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detachedCriteria.getExecutableCriteria(session); Y0R\u\b
return v)X[gt
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criteria.setProjection(Projections.rowCount '` BjRg57]
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()).uniqueResult(); :..E:HdYO
} ljaAB+
}, true); UtHmM,*I
return count.intValue(); AIIBd
} "H/2r]?GT
} !07FsPI#{
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用户在web层构造查询条件detachedCriteria,和可选的 >n@>h$]
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uaZ"x&oZ#
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PaginationSupport的实例ps。 #L).BM
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ps.getItems()得到已分页好的结果集 }kgjLaQ^N
ps.getIndexes()得到分页索引的数组 %BT)oH}
ps.getTotalCount()得到总结果数 QBN=l\m+
ps.getStartIndex()当前分页索引 0e7O#-
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 ~Sn5;g8+\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A1=$kzw{UH
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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 <*b]JY V@
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一下代码重构了。 !<['iM
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我把原本我的做法也提供出来供大家讨论吧: hCOy\[2$
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首先,为了实现分页查询,我封装了一个Page类: "=v J}
java代码: <W^XSk
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/*Created on 2005-4-14*/ [h2p8i'o
package org.flyware.util.page; }y-AoG
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/** l yLK$B?/
* @author Joa s K$Sar
* D3ZT''
*/ iX9[Q0g=oQ
publicclass Page { +2_6C;_DX
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/** imply if the page has previous page */ ^QHMN 7r/
privateboolean hasPrePage; g en3"\Og{
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/** imply if the page has next page */ 8zB+%mcF
privateboolean hasNextPage; EcS-tE4%
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/** the number of every page */ ko7-%+0|]
privateint everyPage; j)lM:vXR
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/** the total page number */ %(wsGNd
privateint totalPage; jJ{
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"
/** the number of current page */ gCBZA;/
privateint currentPage; Ivgwm6M
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/** the begin index of the records by the current J Wyoh|
] !*
query */ Zv7$epDUz
privateint beginIndex; #lVl?F+~
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@OL3&R
/** The default constructor */ MsiC!j.-
public Page(){ ~Sem_U`G
''
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} 1J%qbh
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/** construct the page by everyPage @BQBNGR 1
* @param everyPage JMe[
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* */ fm2M i~}0
public Page(int everyPage){ >A@D;vx
this.everyPage = everyPage; >~bj7M6t
} gZ%O<XO
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/** The whole constructor */ X72X:"
public Page(boolean hasPrePage, boolean hasNextPage, -H]f@|AOw
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int everyPage, int totalPage, s$y#Ufz
int currentPage, int beginIndex){ RlPByG5K
this.hasPrePage = hasPrePage; co%_~xO
this.hasNextPage = hasNextPage; L"^366M!
this.everyPage = everyPage; 0 Ln5e.&
this.totalPage = totalPage; oX]1>#5UMg
this.currentPage = currentPage; |"E9DD]{
this.beginIndex = beginIndex; YGO 7lar
} 2B?i2[a,
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/** #3[b|cL
* @return o)D+qiA3U
* Returns the beginIndex. dGW7,B~
*/ u4^"E+y^S
publicint getBeginIndex(){ U$JIF/MO_
return beginIndex; %[CM;|?B4
} {EHG |
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/** B91PlM.
* @param beginIndex G+^$JN=
* The beginIndex to set. |Ie`L("
*/ hBSJEP
publicvoid setBeginIndex(int beginIndex){ scEQDV
this.beginIndex = beginIndex; Q3{&'|}^2
} e(% Solkm?
1Moh`
/** ,%G2>PBt
* @return LsZ!':LN
* Returns the currentPage. 3kQ8*S
*/ X35U!1Y\
publicint getCurrentPage(){ cZT.vA#
return currentPage; l5nDt$Ex
} 05LQh
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/** ]<z(Rmn`Q
* @param currentPage ffd3QQ
* The currentPage to set. ^aWNtY'
:
*/ nL20}"$E
publicvoid setCurrentPage(int currentPage){ O;t?@!_
this.currentPage = currentPage; G6bg ~V5Q:
} 9yAu<a
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/** ^#nWgo7{7
* @return {S(T1ua
* Returns the everyPage. tX}S[jdq
*/ 3m7V6##+
publicint getEveryPage(){ ]}y'3aW
return everyPage; *uM*)6O 3
} g$LwXfg
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/** agD.J)v\
* @param everyPage WfO$q^'?DP
* The everyPage to set. 8{t&8Ql n
*/ ha~s<
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publicvoid setEveryPage(int everyPage){ 3mz>Y*^?0
this.everyPage = everyPage; }"k(kH
} HNT8~s.2
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/** r0bPaAKw
* @return T
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* Returns the hasNextPage. >vy+U
*/ mj|9x1U)
publicboolean getHasNextPage(){ [
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return hasNextPage; X+@,vCC
} AE
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/** p ivS8C
* @param hasNextPage 2oASz|
* The hasNextPage to set. @'4D9A
*/ bOKNWI
publicvoid setHasNextPage(boolean hasNextPage){ giJyMd}x
this.hasNextPage = hasNextPage; RVx<2,['
} k<qH<<r*
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/** zSCPp6
* @return "PtH
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* Returns the hasPrePage. *^_!W'T{j
*/ \M@8# k|
publicboolean getHasPrePage(){ h_!"CF<n
return hasPrePage; gv-k}2u_
} s'4p+eJ
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/** Hm*#HT%#
* @param hasPrePage ;d40:q<
* The hasPrePage to set. {NDP}UATw
*/ &nProzC
publicvoid setHasPrePage(boolean hasPrePage){ >YhqL62!a
this.hasPrePage = hasPrePage; SbivW5|61
} X_l,fu^C#$
)v0vdAh'b
/**
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* @return Returns the totalPage. hBu=40K
* KW<CU'
*/ Um<vsR
publicint getTotalPage(){ -Ma"V
return totalPage; tEs$+b
} ` 454=3H
JM%#L *;
/** +dv@N3GV
* @param totalPage {%Sww:
* The totalPage to set. ?|dz"=y
*/ h6t>yC\
publicvoid setTotalPage(int totalPage){ 1 Y&d%AA
this.totalPage = totalPage; R&0l4g-4>
} Y~xZ{am
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} 6 -}gqkR
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 qQ_QF
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个PageUtil,负责对Page对象进行构造: \2!$HA7P
java代码: !Ao?bs'
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/*Created on 2005-4-14*/ Sj?'T@
package org.flyware.util.page; VUb*,/hxa
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import org.apache.commons.logging.Log; D~:fn|/Brp
import org.apache.commons.logging.LogFactory; s-B\8&^C
X'm2uOEj
/** x?IT#ty
* @author Joa *&D=]fG
* -E7\.K3
*/ i_"I"5pBF
publicclass PageUtil { xjN~Y D:
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privatestaticfinal Log logger = LogFactory.getLog f7'%AuSQ(
guvQISQlY
(PageUtil.class); d}Om?kn
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/** Kf.b
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* Use the origin page to create a new page 6X7_QBC)
* @param page (Wn'.|^%
* @param totalRecords H =jnCGk
* @return ]!N5jbA@
*/ =j0V/=
publicstatic Page createPage(Page page, int [>;O'>
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totalRecords){ \<} nn?~n
return createPage(page.getEveryPage(), xcig'4L
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page.getCurrentPage(), totalRecords); u#\3T>o%@
} $$@Tgkg?o
? &O$ayG77
/** r!S iR(
* the basic page utils not including exception o2~x'*A0I
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handler (`xc3-,
* @param everyPage qU}DOL|
* @param currentPage CS/-:>s%
* @param totalRecords =%L^!//c
* @return page "{k3~epYaN
*/ 9M<? *8)
publicstatic Page createPage(int everyPage, int VsC]z,
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currentPage, int totalRecords){ zP9!fA
everyPage = getEveryPage(everyPage); o;.-I[9h]
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, nTAsy0p]
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currentPage); }5k"aCno
int totalPage = getTotalPage(everyPage, $sJn:
8z
{ at;
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totalRecords); /y 0 )r.R
boolean hasNextPage = hasNextPage(currentPage, fp7Qb $-A
Ssj'1[%
totalPage); 89paR[
boolean hasPrePage = hasPrePage(currentPage); 4v>V7T.
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returnnew Page(hasPrePage, hasNextPage, ( ;"ICk&
everyPage, totalPage, b Y>Ug{O;
currentPage, +3C
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JG[+e*8
beginIndex); 6voK{C4J
} o$-Phl
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privatestaticint getEveryPage(int everyPage){ Z9U*SS5s,
return everyPage == 0 ? 10 : everyPage; h@J`:KO
} )d(cXN-T
(]1%s?ud*
privatestaticint getCurrentPage(int currentPage){ ^tah4QmUA
return currentPage == 0 ? 1 : currentPage; zE[c$KPP
} N(9'U0z
k2=uP8
privatestaticint getBeginIndex(int everyPage, int \;3r
L,WKL.
currentPage){ =4zsAa
return(currentPage - 1) * everyPage; HiC\U%We
} ,'!&Z *
`#R$
privatestaticint getTotalPage(int everyPage, int r#XDgZtI
& zG=
totalRecords){ 1Jahu!c?
int totalPage = 0; 8.,PgS
SBEJ@&iB~
if(totalRecords % everyPage == 0) BjH(E'K[b
totalPage = totalRecords / everyPage; en
else ;cO0Y.V9l
totalPage = totalRecords / everyPage + 1 ; >eC^]#c
bfJDF(=h
return totalPage; ZD,l2DQ?
} 8[DD=[&
4MM#\
privatestaticboolean hasPrePage(int currentPage){ Dihk8qJ/6
return currentPage == 1 ? false : true; j<!$ug9VA
} 982$d<0%
4nY2v['m0
privatestaticboolean hasNextPage(int currentPage, GB+G1w
ESs)|t h
int totalPage){ h*d,AJz &.
return currentPage == totalPage || totalPage == yR`-rJb V
(~P&$$qfD
0 ? false : true; WDZEnauE
} .Ybm27Dk
F kWJB>
^I0SfZ'Y
} {<GsM
65AOFH
+z4NxR
EU+sTe >
v}!,4,]:&
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。 cq 0jM;@d
]8mBFr5E9
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 %:??QD*
ENGw <
做法如下: &~k/G
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 V=YK3){>A
PY^Yx$t9
的信息,和一个结果集List: ?FA:K0H?zl
java代码: %B~`bUHjq
oCduY2
34oC285yc
/*Created on 2005-6-13*/ oreSu;`$
package com.adt.bo; cZwQ{9>
g~cWBr%>
import java.util.List; %|;^[^7+}t
WaHTzIa[
import org.flyware.util.page.Page; i{`>!)U
8^^al!0K~
/** "u%$`*
* @author Joa 7
724,+2N
*/ tuv4~i<
publicclass Result { 0{j>u`
ZQyT$l~b
private Page page; R ~cc]kp0
3*FktXmI}
private List content; 1D*eu
, vky
/** f6m^pbQFl
* The default constructor "aP/214Ul
*/ -Wmpj
public Result(){ P017y&X
super(); r2Q"NVw
} -<|Ebh d3
vv3dr_l:
/** o?b"B+#
* The constructor using fields
3{:d$- y
* M~@\x]p >
* @param page ak NJL\b
* @param content F~{4)`
*/ sx/g5?zh
public Result(Page page, List content){ I\[*vgjm3G
this.page = page; SkK=VeD>8
this.content = content; e\P+R>i0
} J+9D/VT
HHX9QebiST
/** A\=:h AQ
* @return Returns the content. 0AaN
*/ >8RIMW2
publicList getContent(){ x.d9mjLN8m
return content; Jb0]!*tV
} 02S Uyv(Mt
]qXfgc
/** @]cpPW-b
* @return Returns the page. wngxVhu8Ld
*/ pHWol!
public Page getPage(){ Uqkh@-6-
return page; BG'gk#J+f
} %`` FIv15w
`E}2|9
/** 8x+K4B"oe
* @param content jL2f74?1
* The content to set. A?_2@6Y^
*/ ~>C!l k
public void setContent(List content){ EmLPq!C
this.content = content; yqoi2J:
} ~ 9'64
^tpy8TQ
/** [7$<sN<'
* @param page s cn!,
* The page to set. *yt/
Dj
*/ `RjcJ?r
publicvoid setPage(Page page){ H-I*;
this.page = page; Ue8_Q8q5
} ; I=z
} E
fqa*,k
c>]_,Br~
ZkqC1u3
ka]n+"~==\
y{kXd1,
2. 编写业务逻辑接口,并实现它(UserManager, (2%C%#]8
zO!`sPP
UserManagerImpl) A]R"C:o
java代码: BL]^+KnP
S?D2`b
^%\p; yhL
/*Created on 2005-7-15*/ (s}9N
package com.adt.service; *A_
A@`C<O ^
import net.sf.hibernate.HibernateException; @GGyiK@
~r!j VK>^
import org.flyware.util.page.Page; 8o~\L=
l
_msDf2e9
import com.adt.bo.Result; !4
6^}3
:CH'Bt4<
/** {Q4=GrS
* @author Joa 'o5[:=K
*/ uD. 0?*_
publicinterface UserManager { IMVoNKW-
^\x
PF5
public Result listUser(Page page)throws C8(sH @
6.ap^9AD
HibernateException; n+xM))
mv+.5X
} 71wyZJ
o2%"Luf<
bk5~t'
sX@e1*YE_
dLjT^ 9
java代码: _I@dt6oF
+LrW#K;
B [y1RI|9
/*Created on 2005-7-15*/ K5k,47"
package com.adt.service.impl; ukri7 n*
@89mj{
import java.util.List; &\1Dy}:
ay4|N!ExO
import net.sf.hibernate.HibernateException; 5nEvnnx0
slw^BK3t
import org.flyware.util.page.Page; ~-.q<8
import org.flyware.util.page.PageUtil; !hJ%{.
Y/{Z`}
import com.adt.bo.Result; 6#dx%TC
import com.adt.dao.UserDAO; .%D] z{''
import com.adt.exception.ObjectNotFoundException; 6g$+ ))g
import com.adt.service.UserManager; ,m0=zH4+:
s'/ug
/** 64zO%F*
* @author Joa D4`7,JC}<
*/ d'DS7F(c{
publicclass UserManagerImpl implements UserManager { I|BLAm6j
Ph-3,cC
private UserDAO userDAO; ,/Xxj\i
E?%k
/** 'zRd?Z>%
* @param userDAO The userDAO to set. w}7`Vas9
*/ w/ZV9"BhE
publicvoid setUserDAO(UserDAO userDAO){ FUMAvVQ
this.userDAO = userDAO; viKN:n! Ev
} Kz 'W
|
ujDAs%6MZ
/* (non-Javadoc) S,J'Z:spf
* @see com.adt.service.UserManager#listUser M~3(4,
MLL2V`vBT
(org.flyware.util.page.Page) `t#C0
*/ 3{,Mpb@
public Result listUser(Page page)throws spAYb<
c*LnLK/m
HibernateException, ObjectNotFoundException { Be-gGJG
int totalRecords = userDAO.getUserCount(); =(zk-J<nY
if(totalRecords == 0) `(16_a
throw new ObjectNotFoundException G.c s-f
W>s<&Vb
("userNotExist"); EEF}Wf$f
page = PageUtil.createPage(page, totalRecords); ~|?2<g$gYR
List users = userDAO.getUserByPage(page); UlQ }
returnnew Result(page, users); !74*APPHR
} 8vnU!r
VRMlr.T+
} '?Hy"5gUA
M}us^t*
qOkw6jfluh
i"U3wt|A
F5)Ta?3|"<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,{YC|uB
P`RM"'Om
询,接下来编写UserDAO的代码: GAPZt4Z2
3. UserDAO 和 UserDAOImpl: mo<g'|0
java代码: H2|w
l*pCG`@J#
US4X CJxB
/*Created on 2005-7-15*/ vChkSY([
package com.adt.dao; #16)7
vE{QN<6T
import java.util.List;
%lEPFp
YIjBKh
import org.flyware.util.page.Page;
c9DX
6V!yfps)
import net.sf.hibernate.HibernateException; E&]S No<
Jg: Uv6eN+
/** >uxak2nM-
* @author Joa vzy/Rq
*/ IHf
A;&b
publicinterface UserDAO extends BaseDAO { -3haLdRk6
0]NjsOU=
publicList getUserByName(String name)throws EYMwg_
A qE,zW
HibernateException; +U@P+;
i Ri1E;
publicint getUserCount()throws HibernateException; m;8_A|$A
"xYMv"X
publicList getUserByPage(Page page)throws {}vW=
iZ)7%R?5
HibernateException; +^4"
dqPJ 2j $\
} i_f"?X;D
>>K)
4HYID
yBq4~b~[
P0UMMn\-#
awo=%vJ&
java代码: b(K.p? bt
3{~hRd
hnH:G`[F
/*Created on 2005-7-15*/ /C_O/N
package com.adt.dao.impl; _d)w, ;m#
O^|,Cbon6
import java.util.List; "'s`?
tz._*n83
import org.flyware.util.page.Page; CuU"s)
^#XxqVdPk
import net.sf.hibernate.HibernateException; ;I]TM#qGF
import net.sf.hibernate.Query; Hm1C|Qb
$ 'HiNP
{c
import com.adt.dao.UserDAO; &)<]AG.vd!
ENjrv
/** T%-F,i
* @author Joa Hq6VwQu?
*/ Wf>UI)^n
public class UserDAOImpl extends BaseDAOHibernateImpl Z
A7u66
R4pbi=
implements UserDAO { Zo'lvOpyZ
*Cj]j-
/* (non-Javadoc) `Fu|50_@V
* @see com.adt.dao.UserDAO#getUserByName ,T"(97"
3p$ZHH.UP
(java.lang.String) Qa(u+
*/ }+ I
8l'
publicList getUserByName(String name)throws .r[J} O"
LlnIn{C
HibernateException { W=PDOzB>K
String querySentence = "FROM user in class R+rHa#M_
l
AE$HP'o
com.adt.po.User WHERE user.name=:name"; *slZ17xg
Query query = getSession().createQuery I3s'44
i1 C]bUXA
(querySentence); I-&/]<5y
query.setParameter("name", name); Lp1wA*
return query.list(); RhX
2qsva-
} TDy@Y>
)
dax|4R
/* (non-Javadoc) k$3.FO"
* @see com.adt.dao.UserDAO#getUserCount() c-z=(Z
*/ @DY0Lz;
publicint getUserCount()throws HibernateException { v>7t J[s
int count = 0; q>!T*BQ
String querySentence = "SELECT count(*) FROM m <aMb
&A=d7ASN=
user in class com.adt.po.User"; 9`-ofwr'|
Query query = getSession().createQuery ]^ZC^z;H
2|w(d
(querySentence); D[:7B:i
count = ((Integer)query.iterate().next Qt]nlu i~
1QjrL@$>15
()).intValue(); *E+)mB"~
return count; 8I NVn'G
} "x3_cA~
[Z~>7ayF+)
/* (non-Javadoc) Z*jhSy
* @see com.adt.dao.UserDAO#getUserByPage ely&'y!
wp.'M?6`L
(org.flyware.util.page.Page) B=|yjA'Fg
*/ tAbIT;>
publicList getUserByPage(Page page)throws -D38>#Y
/xj'Pq((}p
HibernateException { y)Ip\.KV\
String querySentence = "FROM user in class E5-8tHV
1[u{3lQ
com.adt.po.User"; ft:/-$&H
Query query = getSession().createQuery Ya304Pjd
LPewo AXO
(querySentence); hFylQfd
query.setFirstResult(page.getBeginIndex()) "R4~
8 r
.setMaxResults(page.getEveryPage()); $N:m
9R
return query.list(); 8Bo'0
} kZPj{^c:
cg0L(oI~
} in(n[K
P8z++h
]
M_[*OAb
jk) V[7P
|VaXOdD`&
至此,一个完整的分页程序完成。前台的只需要调用 "2Js[uf
g7_a8_
userManager.listUser(page)即可得到一个Page对象和结果集对象 ~ EE*/vX
%C'!L]#
的综合体,而传入的参数page对象则可以由前台传入,如果用 )x?F1/
>SSF:hI"J
webwork,甚至可以直接在配置文件中指定。 D#^v=U
$].< /
下面给出一个webwork调用示例: Gd:fWz(
java代码: 3U1xKF
^9qncvV
;l}TUo
/*Created on 2005-6-17*/ vJmE}
package com.adt.action.user; @ iao"&
]5rEwPB
import java.util.List; DV{Qbe#In
B7N?"'$i
import org.apache.commons.logging.Log; EDL<J1%
import org.apache.commons.logging.LogFactory; )5'S=av9
import org.flyware.util.page.Page; yd`.Rb&V
f0MHh5
import com.adt.bo.Result; R"=G?d)
import com.adt.service.UserService; @qg=lt|(F
import com.opensymphony.xwork.Action; 1fEV^5I
V"T;3@N/4
/** cnhYrX^
* @author Joa 5FH#)
*/ VGq2ITg9eE
publicclass ListUser implementsAction{ |CStw"Fog
d=H C;T)
privatestaticfinal Log logger = LogFactory.getLog i#(T?=VPcy
(fY (-
(ListUser.class); LT:KZ|U9
7&l
private UserService userService; 0Oe@0L%^3"
Z</$~
T
private Page page; B>|@XfPM
]#+fQR$!
privateList users; 3 T&m
0o(/%31]
/* QJ>+!p*
* (non-Javadoc) g0_8:Gs}^
* jNrGsIY$
* @see com.opensymphony.xwork.Action#execute() j/dNRleab
*/ AGPZd9
publicString execute()throwsException{ !3?HpR/nV
Result result = userService.listUser(page); YuLW]Q?v
page = result.getPage(); 6M259*ME
users = result.getContent(); %hcY
[F<
return SUCCESS; 6
)xm?RK
} spd>.Cm`
?ry`+nx
/** #LBZ%%v
* @return Returns the page. s.Yyw y
*/ .i@e6JE~;
public Page getPage(){ ECU:3KH>MF
return page; ? 0nbvV5v7
} (Cqhk:F
)[G5qTO
/** Jr
9\j3J{
* @return Returns the users. v:s~Y
*/ [ V/*{Z
publicList getUsers(){ tb{l(up/a
return users; \BUr2]
} L[Tr"BW
?w /tq!
/** SP5/K3t-*
* @param page U1J?o#(
* The page to set. ks:Z=%o
*/ NfDg=[FN[
publicvoid setPage(Page page){ p>65(&N,
this.page = page; >k
kuw?O@
} 0.t;i4
<EJ}9`t
/** y$K!g&lGA
* @param users Fag%#jxI
* The users to set. vMj"%
*/ ~Ci|G3BW
publicvoid setUsers(List users){ F|%[s|s
this.users = users; fZT=q^26
} ^Shz[=fd
@ 5|F:J
/** tE=P9 \4
* @param userService 6\/C]![%
* The userService to set. ?uOdqMJV
*/ f!0* ^d
publicvoid setUserService(UserService userService){ 6'+3""\
this.userService = userService; ZU7,=B=
} /&cb`^"U^
} rFdq \BSi
wUW+S5"K
\ec,=7S<Zf
7 45Uo'
{b=]JPE
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, 2c_#q1/Z/
vX/~34o]\
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 ?psvhB{O
UR:cBr
么只需要: SWPr5h
java代码: $iupzVrro
Jc(tV(z
yG2j!D
<?xml version="1.0"?> Nt'(JAZ;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^)D[ W(*
u])N^AY"sj
1.0//EN" "http://www.opensymphony.com/xwork/xwork- kd9hz-*
d7N}-nsB
1.0.dtd"> b P4R
]k
"
j
<xwork> !T#~.QP4
,*}SfCon
<package name="user" extends="webwork- (7;}F~?h
2u/~#Rt&*
interceptors"> uiP fAPZ
.@gv}`>
<!-- The default interceptor stack name Y
u8a8p|
nO,<`}pV
--> _<yJQ|[z~i
<default-interceptor-ref A +e
={-*
K
p~x
name="myDefaultWebStack"/> p4*VE5[?_+
o}
YFDYi
<action name="listUser" |!aMj8i2
vp{jh-&
class="com.adt.action.user.ListUser"> jDqe)uVvtV
<param Vf`1'GY
"U4Sn'&h@
name="page.everyPage">10</param>
4b,N"w{v
<result {%)bxk6
Z)~.OqRw]
name="success">/user/user_list.jsp</result> aP>%iRk'J!
</action> )lTkqz8v
Z455g/=ye
</package> $NWXn,Y'
N3!x7J7A
</xwork> 7D@O:yO
>Ke4lO"
F)z]QJOw
?MHVkGD
`p|{(g'
-WWa`,:
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 <=W;z=$!Bb
T&H[JQ/h
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。 WSz#g2a
xrFFmQ<_W
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )}0(7z
Yu
cz~Fz;)2{N
{F+7> X
}q^M
`b=?z%LuT
我写的一个用于分页的类,用了泛型了,hoho C4H M
y)0r%=
java代码: vUk <z*
5A g4o
[y7BHikX)
package com.intokr.util; !_3Rd S
dq+VW}[EO
import java.util.List; Z@nWx]iz
mJ2>#j;5f
/** Y;O\ >o[
* 用于分页的类<br> C!6?.\U/:c
* 可以用于传递查询的结果也可以用于传送查询的参数<br> P:eY>~m<;
* q"7rd?r52
* @version 0.01 D(yU:^L
* @author cheng PHU#$LG
*/ bS=aFl#
public class Paginator<E> { 56Z 1jN^U
privateint count = 0; // 总记录数 B[%FZm $`M
privateint p = 1; // 页编号 oKLL~X>!U
privateint num = 20; // 每页的记录数 }1=V`N(
privateList<E> results = null; // 结果 oJE~dY$Q
.bE+dA6:v
/** ~Gx"gK0
* 结果总数 A>8"8=C
*/ vq-Tq>
publicint getCount(){ ]:uJ&xUar