Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 AQ^u
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 EKN~H$.
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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 'Z]w^<
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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 2B`JGFcdcB
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分页支持类: ^=*;X;7
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java代码: ?&uu[y
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package com.javaeye.common.util; f?)-}\[IR{
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import java.util.List; WfRXP^a
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publicclass PaginationSupport { -ze J#B)C
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publicfinalstaticint PAGESIZE = 30; -7|H}!DFT
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privateint pageSize = PAGESIZE; Y\hBd$lQ~
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privateList items; HOJV,9v N
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privateint totalCount; /<BI46B\
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privateint[] indexes = newint[0]; Z #m+ObHK1
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privateint startIndex = 0; -DAlRz#d,
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public PaginationSupport(List items, int ]]Ufas9
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totalCount){ uvS)8-o&F
setPageSize(PAGESIZE); xe$_aBU
setTotalCount(totalCount); Dum9lj
setItems(items); [1H^3g
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setStartIndex(0); ]J]h#ZHx
} HkVB80hv
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public PaginationSupport(List items, int z([</D?
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totalCount, int startIndex){ l}M!8:UzU
setPageSize(PAGESIZE); 7 Fsay+a
setTotalCount(totalCount); ,9
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setItems(items); zp?`N;
setStartIndex(startIndex); |
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} +8ZF"{y
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public PaginationSupport(List items, int bi;1s'Y<D
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totalCount, int pageSize, int startIndex){ T^]}Oy@e,J
setPageSize(pageSize); %vi83%$'4
setTotalCount(totalCount); IV)j1
setItems(items); S:ztXhif>
setStartIndex(startIndex); FHI ;)wn=
} )@bQu~Y
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publicList getItems(){ %ULr8)R;
return items; ^5
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} 63 B?.
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publicvoid setItems(List items){ Aq7osU1B
this.items = items; 0_t!T'jr7
} Uf+%W;}
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publicint getPageSize(){ S>1Iky|
return pageSize; -A!%*9Z
} KKf
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publicvoid setPageSize(int pageSize){ FaJ &GOM,
this.pageSize = pageSize;
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} z2>lI9D4V
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publicint getTotalCount(){ hY8reQp1
return totalCount; VyGJ=[ ]
} N ZSSg2TX#
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publicvoid setTotalCount(int totalCount){ .kfIi^z
if(totalCount > 0){ &@YmA1Yu)E
this.totalCount = totalCount;
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int count = totalCount / {Y9q[D'g .
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pageSize; 6)Lk-D
if(totalCount % pageSize > 0) tIgN$BHR>
count++; i~J'% a<Qp
indexes = newint[count]; wj0\$NQ=x
for(int i = 0; i < count; i++){ 6!FQzFCZq
indexes = pageSize * VP]% Hni]
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} Th%Sjgsn
}else{ y'*K|aTG
this.totalCount = 0; |Xy6PN8
} 4{`{WI{
} U/NoP4~{
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publicint[] getIndexes(){ }vM("v|M
return indexes; R~$qo)v
} V~5jfcd
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publicvoid setIndexes(int[] indexes){ 4r}8lpF_(
this.indexes = indexes; D,FkB"ZZE
} BThrO d
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publicint getStartIndex(){ %bfQ$a:
return startIndex; <UQbt N-B\
} '."ed%=MC
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publicvoid setStartIndex(int startIndex){ HA>OkA/
if(totalCount <= 0) n7-6-
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this.startIndex = 0; <e</m)j
elseif(startIndex >= totalCount) y
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this.startIndex = indexes 9qG6Pb
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[indexes.length - 1]; 3/n5#&c\4
elseif(startIndex < 0) Jz e:[MYS
this.startIndex = 0; dlTt_.
else{ ) hfpwdQ
this.startIndex = indexes u4h4.NHX
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[startIndex / pageSize]; Z?m3~L9L2
} `+Q%oj#FF
} ]GQG~H^
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publicint getNextIndex(){ %8~NqS|=
int nextIndex = getStartIndex() + a!AA]
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pageSize; jtc]>]6i
if(nextIndex >= totalCount) NHZz _a=
return getStartIndex(); s,&Z=zt0R
else JnM["Q=`
return nextIndex; 7O-x<P;
} _zi|
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publicint getPreviousIndex(){ 0Z{ZO*rK
int previousIndex = getStartIndex() - ~FG]wNgS
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pageSize; G*P#]eO
if(previousIndex < 0) ^3L0w}#
return0;
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else |_@>*Vmg
return previousIndex; IB]l1<
} @i IRmQ
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} <l E<f+
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抽象业务类 \n|EM@=eE
java代码: .jjG(L
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/** K^<BW(s
* Created on 2005-7-12 hy"\RW
*/ 6fEqqUeV
package com.javaeye.common.business; p]2128kqx
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import java.io.Serializable;
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import java.util.List; )W
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import org.hibernate.Criteria; _H7x9
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import org.hibernate.HibernateException; -ifFbT+x
import org.hibernate.Session; >$/>#e~
import org.hibernate.criterion.DetachedCriteria; N]=q|D
import org.hibernate.criterion.Projections; `Cynj+PCe
import [MM~H0=s
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org.springframework.orm.hibernate3.HibernateCallback; ~YWQ2]
import =|y9UlsD
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org.springframework.orm.hibernate3.support.HibernateDaoS YWO)HsjP
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upport; oDA XiY$u
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import com.javaeye.common.util.PaginationSupport; LxSpctiNx
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public abstract class AbstractManager extends 0#Y5_i|p
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HibernateDaoSupport { \aUC(K~o\;
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privateboolean cacheQueries = false; Ed df2;-.
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privateString queryCacheRegion; t:
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publicvoid setCacheQueries(boolean |tMWCA
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cacheQueries){ m6\E$;`
this.cacheQueries = cacheQueries; qUW!
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} b;W3j
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publicvoid setQueryCacheRegion(String G+"t/?/
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queryCacheRegion){ */^q{PsN
this.queryCacheRegion = :W.(S6O(
{
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queryCacheRegion; %i9E @EV
} y@: h4u"3
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publicvoid save(finalObject entity){ F Q7T'G![
getHibernateTemplate().save(entity); M2>Vj/
} Fg5kX
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publicvoid persist(finalObject entity){ c%2QZ C
getHibernateTemplate().save(entity); p{Yv3dNl
} qYjce]c
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publicvoid update(finalObject entity){ y^,1a[U.
getHibernateTemplate().update(entity); sV{,S>s
} +mmSfuO&\
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publicvoid delete(finalObject entity){ Pw7]r<Q
getHibernateTemplate().delete(entity); +,TRfP
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} i&Tbz!
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publicObject load(finalClass entity, @; zl
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finalSerializable id){ 6y%qVx#!
return getHibernateTemplate().load zU kgG61
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(entity, id); B4c]}r+
} ?*G|XnM&
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publicObject get(finalClass entity, 7u -p%eq2
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finalSerializable id){ Ga-k
return getHibernateTemplate().get P_dCR
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(entity, id); M)J5;^["
} EnKR%Ctw
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publicList findAll(finalClass entity){ &=@IzmA
return getHibernateTemplate().find("from 3Gp$a;g
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" + entity.getName()); GfxZ'VIn
} |B?m,U$A!
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publicList findByNamedQuery(finalString Go`vfm"S
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namedQuery){ !_]Y~[
return getHibernateTemplate tVYF{3BhA
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().findByNamedQuery(namedQuery); :T^a&)aL%
} R$h<<v)%
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publicList findByNamedQuery(finalString query, BA @lk+aW
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finalObject parameter){ +xh`Q=A
return getHibernateTemplate G)AqbY
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().findByNamedQuery(query, parameter); wjU9ZGM
} 9a[9i}_
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publicList findByNamedQuery(finalString query, <O(4TO
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finalObject[] parameters){ _>o:R$ %}
return getHibernateTemplate j"8ZM{aO
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().findByNamedQuery(query, parameters); #>a\>iKQ2q
} I {SjlN}d
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publicList find(finalString query){ ^)470K`%)
return getHibernateTemplate().find H9Gh>u]}
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(query); vRYQ{:
} ` _6C{<O
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publicList find(finalString query, finalObject .y'>[
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parameter){ {Ea
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return getHibernateTemplate().find ,=uD^n:
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(query, parameter); h<h%*av|
} K$z2YJ%
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public PaginationSupport findPageByCriteria f'F?MINJP
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(final DetachedCriteria detachedCriteria){ QDZWX`qw{
return findPageByCriteria 3h]g}&k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); YByLoM*
} V~qNyOtA]
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public PaginationSupport findPageByCriteria 05|=`eJ
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(final DetachedCriteria detachedCriteria, finalint MnmVl"(/
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startIndex){ 1l9G[o
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return findPageByCriteria Oz.HH
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(detachedCriteria, PaginationSupport.PAGESIZE, 4a&RYx
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startIndex); //B&k`u
} ;2G*wR
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public PaginationSupport findPageByCriteria Xa[.3=bV?
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(final DetachedCriteria detachedCriteria, finalint HH`'*$]7
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pageSize, YH$-g
finalint startIndex){ pR<`H'
return(PaginationSupport) JhYe6y[q
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getHibernateTemplate().execute(new HibernateCallback(){ *9
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publicObject doInHibernate b\f
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(Session session)throws HibernateException {
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Criteria criteria = KV91)U
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detachedCriteria.getExecutableCriteria(session); Fk7?xc
int totalCount = "> ypIR<
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((Integer) criteria.setProjection(Projections.rowCount 8H[<X_/ke
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()).uniqueResult()).intValue(); TT%M'5&
criteria.setProjection _IMW{
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(null); Brw@g8w-X
List items = t}a: p6D]
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criteria.setFirstResult(startIndex).setMaxResults A.F%Ycq
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(pageSize).list(); ?Rb9|`6
PaginationSupport ps = 4X/-4'
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new PaginationSupport(items, totalCount, pageSize, E#RDqL*J
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startIndex); xa'*P=<)C'
return ps; JBj]najN
} 8bGd} (
}, true); E*&vy
} B^=-Z8
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public List findAllByCriteria(final @)F )S7
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DetachedCriteria detachedCriteria){ >dXGee>'M
return(List) getHibernateTemplate -]Bq|qTH[(
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().execute(new HibernateCallback(){ 'c&Ed
publicObject doInHibernate T.F!+
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(Session session)throws HibernateException { P;y45b
Criteria criteria = RU{twL.B
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detachedCriteria.getExecutableCriteria(session); bRDYGuC
return criteria.list(); e
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} E`JI>7
}, true); 234p9A@
} LrfVh-}|:Y
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public int getCountByCriteria(final <{p4V|:
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DetachedCriteria detachedCriteria){ ;}WeTA_-[
Integer count = (Integer) mUC)gA/
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getHibernateTemplate().execute(new HibernateCallback(){ w(Ovr`o?9t
publicObject doInHibernate f)rq%N &
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(Session session)throws HibernateException { + 480 l}
Criteria criteria = gaxsv[W>^
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detachedCriteria.getExecutableCriteria(session); g/_5unI}u
return !TH)
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criteria.setProjection(Projections.rowCount 2"Q|+-Io
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()).uniqueResult(); !n!*/[}X
} 8nqG<!,q
}, true); s[*rzoA
return count.intValue(); #zy:a%
} Es`Px_k
} DK~xrU'
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用户在web层构造查询条件detachedCriteria,和可选的 }K>d+6qk5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]c*4J\s
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PaginationSupport的实例ps。 =*.~BG
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ps.getItems()得到已分页好的结果集 (m}'4et~L
ps.getIndexes()得到分页索引的数组 a!SiX
ps.getTotalCount()得到总结果数 pF >i-i
ps.getStartIndex()当前分页索引 r<EY]f^`u
ps.getNextIndex()下一页索引 R^fPIv`q
ps.getPreviousIndex()上一页索引 uMv,zO5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 B mb0cFQ
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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 MJ)RvNF
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一下代码重构了。 I][*j
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我把原本我的做法也提供出来供大家讨论吧: Ee#q9Cx^J
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首先,为了实现分页查询,我封装了一个Page类: }v{LRRi
java代码: *>}@7}f
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/*Created on 2005-4-14*/ 6|=f$a
package org.flyware.util.page; }>|s=uGW
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/** W@IQ^
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* @author Joa ,qwuLBW
* Dy&i&5E.-l
*/ = svN#q5s
publicclass Page { ~8+ Zs
@
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/** imply if the page has previous page */ +`0k Fbx
privateboolean hasPrePage; M3y NAN
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/** imply if the page has next page */ . Efk*
privateboolean hasNextPage; (WJRi:NP?
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/** the number of every page */ t?gic9
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privateint everyPage; T!{w~'=F
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/** the total page number */ 9*wK@yEl
privateint totalPage; 9FR5Jw>t
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/** the number of current page */ ;(%QD
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privateint currentPage; Ax@$+/Z!
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/** the begin index of the records by the current @mBQ?;qlK
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query */ gD?l-RT>
privateint beginIndex; $PPi5f}HD
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/** The default constructor */ bJ%h53
public Page(){ 3"e,qY
#{6/ (X
} xo&_bMO
^
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/** construct the page by everyPage V!=,0zy~Z
* @param everyPage 6 "sSo j
* */ *fxG?}YT
public Page(int everyPage){ 0d&6lqTo
this.everyPage = everyPage; ITBE|b
} G` A4|+W"
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/** The whole constructor */ T^KKy0ZGM
public Page(boolean hasPrePage, boolean hasNextPage, ND;#7/$>
bE. .P&"
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int everyPage, int totalPage, L2z[
int currentPage, int beginIndex){ * u>\57W
this.hasPrePage = hasPrePage; ;^*W+,4WB
this.hasNextPage = hasNextPage; CCx&7f
this.everyPage = everyPage; CTa57R
this.totalPage = totalPage; q} >%8;nm
this.currentPage = currentPage; F41=b4/
this.beginIndex = beginIndex; 3 0H?KAV
} ,"ZMRq
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/** T5h
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* @return tsjrRMR
* Returns the beginIndex. Yq
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*/ %u'ukcL7
publicint getBeginIndex(){ 6&x@.1('z
return beginIndex; 7:1Lol-V
} c@7rqHU-0
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/** Xv^qVn4
* @param beginIndex i/4>2y9/F4
* The beginIndex to set. tD)J*]G
*/ ga +dt
publicvoid setBeginIndex(int beginIndex){ y)@wjH{6
this.beginIndex = beginIndex; K0>zxqY
} yN-9[P8C
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/** f:}
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* @return sgFEK[w.y
* Returns the currentPage. k,*XG$2h
*/ mzgfFNm^G)
publicint getCurrentPage(){ Zy/_
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return currentPage; ;=z:F<Y
} @ 6vIap|
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/** H:|uw
* @param currentPage ygcm|PrS
* The currentPage to set. |6-nbj
*/ xqh
publicvoid setCurrentPage(int currentPage){ F^:3?JA_
this.currentPage = currentPage; 75lA%|
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} N!}f}oF
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/** 6gDN`e,@
* @return {Sh ;(.u^
* Returns the everyPage. z$sT !QL~
*/ 9 68Ez
publicint getEveryPage(){ Pq$n5fZC!
return everyPage; 1% ` Rs
} e0 ecD3
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/** |G<|F`Cj
* @param everyPage ccxNbU
* The everyPage to set.
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*/ i%?* @uj
publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; $`8wJf9@w
} ]SEZaT
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/** Ewz!O`
* @return %hP^%'G
* Returns the hasNextPage. HzsdHH(J
*/ .%-8 t{dt
publicboolean getHasNextPage(){ c+ie8Q!
return hasNextPage; ueNS='+m
} *un^u-;
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/** H5an%kU|j
* @param hasNextPage sLk-x\P]|
* The hasNextPage to set. Id9TG/H7
*/ ]?4hyN
publicvoid setHasNextPage(boolean hasNextPage){ (9)Q ' 'S
this.hasNextPage = hasNextPage; ]:n,RO6
} ['D]>Ot68
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/** BA.uw_^4
* @return XjBD{m(
* Returns the hasPrePage. 7_t'( /yu
*/ zQ PQ
publicboolean getHasPrePage(){ E{(;@PzE
return hasPrePage; xIn:ZKJ'
} :4|4 =mkr
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/** ~TtiO#,t
* @param hasPrePage +ZV5o&V>
* The hasPrePage to set. /9X7A;O
*/ Hn:Crl y#
publicvoid setHasPrePage(boolean hasPrePage){ b.938#3,
this.hasPrePage = hasPrePage; <UCl@5g&
} /wG2vE8e
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/** l^}c!
* @return Returns the totalPage. b,@/!ia
* I-)4YQI
*/ HaYo!.(Fv
publicint getTotalPage(){ ;*J
return totalPage; xSu >
} ,r}6iFu
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/** 7:@'B|
* @param totalPage AXB7oV,xt
* The totalPage to set. Ys7]B9/1O
*/ y{Q
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publicvoid setTotalPage(int totalPage){ I1J-)R+
this.totalPage = totalPage; *1"+%Z^
} =~gvZV-<
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} JXxwr)i
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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 nt<]d\o0
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个PageUtil,负责对Page对象进行构造: Sjj6q`
java代码: CJyevMf'
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}
/*Created on 2005-4-14*/ (k P9hcV
package org.flyware.util.page; xD 7]C|8o
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import org.apache.commons.logging.Log; kx CSs7J/
import org.apache.commons.logging.LogFactory; a9Vi];
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/** n"8Yv~v*2j
* @author Joa EX"yxZ~
* ^rz_f{c]-
*/ L},_.$I?
publicclass PageUtil { /_.|E]
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privatestaticfinal Log logger = LogFactory.getLog )5H?Vh>36
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(PageUtil.class); }0 ?3:A
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/** fV~~J2IK
* Use the origin page to create a new page _v:SP
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* @param page @9:uqsL
* @param totalRecords ]@TCk8d$0
* @return ]###w;
*/ 4e
publicstatic Page createPage(Page page, int y>LBl]
@+DX.9
totalRecords){ fsXy"#mOkD
return createPage(page.getEveryPage(), d_CT$
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page.getCurrentPage(), totalRecords); eH,or ,r
} A(X KyEx
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/** 4z)]@:`}z
* the basic page utils not including exception ABkl%m6xf
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handler _dg\\c
* @param everyPage WzWXE(
* @param currentPage U!]dEW|G
* @param totalRecords 0"#HJA44
* @return page .]Z"C&"N]
*/ T{'RV0%
publicstatic Page createPage(int everyPage, int 0\$2X- c
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currentPage, int totalRecords){ HT@=evV
everyPage = getEveryPage(everyPage); Z :gyz$9w
currentPage = getCurrentPage(currentPage); fy$1YI>!Q
int beginIndex = getBeginIndex(everyPage, d5d@k
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currentPage); JI5Dy>u:
int totalPage = getTotalPage(everyPage, [-&Zl(9&
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totalRecords); IA(5?7x`<
boolean hasNextPage = hasNextPage(currentPage, 7z-[f'EIUI
# "an9<
totalPage); w
= KPT''!
boolean hasPrePage = hasPrePage(currentPage); %)n=x
ne
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returnnew Page(hasPrePage, hasNextPage, Zc2PepIg
everyPage, totalPage, %znc##j)q
currentPage, v,t:+
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beginIndex); n`KY9[0U=
} |hQ;l|SWg
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privatestaticint getEveryPage(int everyPage){ W9)&!&<o
return everyPage == 0 ? 10 : everyPage; pJ{Y
lS{
} D,6:EV"sa
'PHl$f*k
privatestaticint getCurrentPage(int currentPage){ E.f%H(b
return currentPage == 0 ? 1 : currentPage; @WB@]-+J
T
} g=rbPbu
DI%saw
privatestaticint getBeginIndex(int everyPage, int <uJ@:oWG7
7d vnupLh
currentPage){ p#Bi>/C6
return(currentPage - 1) * everyPage; t^L]/$q
} *`U~?q}
e;jdqF~v!
privatestaticint getTotalPage(int everyPage, int a9 G8q>h]O
W4N{S.#!
totalRecords){ +q oRP2
int totalPage = 0; he4(hX^
M`>E|"<
if(totalRecords % everyPage == 0) Yz b XuJ4
totalPage = totalRecords / everyPage; :jf3HG
else X}]-*T|a
totalPage = totalRecords / everyPage + 1 ; [E_9V%^
+@UV?"d
return totalPage; 9r9NxKuAO
} xdPx{"C
3
Jm@oDME_E
privatestaticboolean hasPrePage(int currentPage){ 7<4qQ.deE
return currentPage == 1 ? false : true; [g,}gyeS(
} vO=fP_
)7@0[>
privatestaticboolean hasNextPage(int currentPage, !-bB559Nv
f$( e\++
int totalPage){ |Tw~@kT@
return currentPage == totalPage || totalPage == %O<BfIZ
b>k y
0 ? false : true; XW9!p.*.U
} `oJ [u:b
]n~V!hl?A
*hrd5na
} CLSK'+l
hZ3bVi)L\
}u|q0>^8
Rcv9mj]l
E7hhew
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。
)jj0^f1!j
J4utIGF
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 0x7'^Z>-oe
9L9sqZUB
做法如下: <i[HbgUlO.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 d-m7}2c
Cw%{G'O
的信息,和一个结果集List: $(
)>g>%
java代码: 0V]s:S
;4a{$Lw~^9
YqG7h,F
/*Created on 2005-6-13*/ e)ZUO_Q$
package com.adt.bo; u-TUuP
'yth'[
import java.util.List; Q?T]MUY(L
!W0v >p
import org.flyware.util.page.Page; Jwp7gYZ
^{{ qV
/** *=n:-
* @author Joa X8|EHb<
*/ +V+a4lU14
publicclass Result { f)!Z~t &
&~!Wym
private Page page; :EH=_"
M;NX:mX9
private List content; jal-9NV)!
f5k6`7Vj]
/** KG@8RtHsQ
* The default constructor 9cgUT@a
*/ ;]fs'LH
public Result(){ /> Nt[o[r
super(); Zov~B-Of:
} AEuG v}#
8_tQa^.n\
/** 4=.so~9odX
* The constructor using fields ]d`VT)~vje
* bfO=;S]b!
* @param page {U1m.30n
* @param content w:l"\Tm
*/ to\Ni~a&
public Result(Page page, List content){ e*!kZAf
this.page = page; x :7IIvP
this.content = content; CNIsZv@Q
} J=L5=G7(
5?L<N:;J_
/** 66 Tpi![
* @return Returns the content. Ewm9\qmg
*/ p#[.{
publicList getContent(){ T)CP2U
return content; f-2c0Bi
} (ik\|y% A
^t"'rD-I
/** Wl Sm
* @return Returns the page. XUw/2"D'?
*/ G\?YK.Y>
public Page getPage(){ p:%loDk
return page; 8Eq7Sa
} }75e:w[
D-4f.Tq4#
/** d[35d J7F
* @param content g1o8._f.
* The content to set.
BB'OCN
*/ '\GbmD^F
public void setContent(List content){ HmwT~
this.content = content; @A5?3(e
} d/Q%IeEL.
?
qA]w9x
/** E!#WnSpnK
* @param page ]tDDq=+v
* The page to set. :eg4z )
*/ '=6\v!
publicvoid setPage(Page page){ 9S -9.mvop
this.page = page; B]$GSEB
} \15nSB
} Yuc> fFA
r4f~z$QK
)Beiu*
^KELKv,_
veRm2LSP
2. 编写业务逻辑接口,并实现它(UserManager, 4{l,
7!$^r$t
UserManagerImpl) w\brVnt
java代码: #u
+ v_
yOg+iFTr
69 o7EA
/*Created on 2005-7-15*/ |a%Tp3Q~
package com.adt.service; :\}(&
>
-R6)ROGl
import net.sf.hibernate.HibernateException; [=_jYzD,j|
sse.*75U
import org.flyware.util.page.Page; Z`BK/:vo3H
0C*7K?/
import com.adt.bo.Result; -o.:P>/
Rx|;=-8zg
/** _Y[bMuUb=
* @author Joa kE(mVyLQ
*/ 0{[,E.
publicinterface UserManager { Lu0x
(/
gRT00
public Result listUser(Page page)throws 'XBFv9&
CsifKHI
HibernateException; a -moI+y
f>Jr|#k
} ~F?u)~QZ#
]]juN
m<g~H4
@jlw_ob2g
@{pLk4E
java代码: HgkC~'
E\2%E@0#
]P2"[y
/*Created on 2005-7-15*/ ^Js9 s8?$
package com.adt.service.impl; M[112%[+4
")HFYqP>9
import java.util.List; -8rjgB~."/
)Iq <+IJ
import net.sf.hibernate.HibernateException; LRMx<X8
78%~N`x7
import org.flyware.util.page.Page; QS]1daMIK<
import org.flyware.util.page.PageUtil; 9lDhIqx0~
*``JamnSO
import com.adt.bo.Result; =6|&Jt
import com.adt.dao.UserDAO; O|N{v"o
import com.adt.exception.ObjectNotFoundException; ?_"ik[w}
import com.adt.service.UserManager; (41|'eB\\
Yr=Y@~ XL
/** hzbw>g+
* @author Joa @<]Ekkg
*/ 3nnJ8zQ
publicclass UserManagerImpl implements UserManager { 'D"C4;X
:+|Z@KB
private UserDAO userDAO; M6-&R=78K
A;|D:;x3G
/** 'xg
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* @param userDAO The userDAO to set. j;iAD:nf
*/ =-lb)Z"d
publicvoid setUserDAO(UserDAO userDAO){ @Sbe^x
this.userDAO = userDAO; f/Bp.YwL
} n%s]30Xs
:s6o"VkW
/* (non-Javadoc) (<oyN7NT
* @see com.adt.service.UserManager#listUser 'V=P*#|SR
"s_lP&nq
(org.flyware.util.page.Page) QM#4uI55B
*/ E5lBdM>2
public Result listUser(Page page)throws 4l45N6"
*zL}&RUKM
HibernateException, ObjectNotFoundException { '9j="R;
int totalRecords = userDAO.getUserCount(); 8- %TC\:
if(totalRecords == 0) !pdb'*,n
throw new ObjectNotFoundException ~-J]W-n
rOOT8nkR#
("userNotExist"); ><$d$(
page = PageUtil.createPage(page, totalRecords); 1gy.8i
List users = userDAO.getUserByPage(page); qC:raH_:
returnnew Result(page, users); ~C`^6UQr/?
} os={PQRD
)MchsuF<
} <drODjB
;^%4Q"
MgrLSKLT
c>Xs&_
LS*y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 wlk4*4dKn
9-DZU,`P
询,接下来编写UserDAO的代码: [knN:{ l
3. UserDAO 和 UserDAOImpl: $m1z-i;/
java代码: 'JfdV%M
gSUcx9f]
i?g5_HI
/*Created on 2005-7-15*/ fNt`?pWH
package com.adt.dao; )ZqTwEr@[
I3mGo
import java.util.List; b+6\JE^Mz
,>-< (Qi
import org.flyware.util.page.Page; [@b&? b~K
OFv%B/O
import net.sf.hibernate.HibernateException; _5# y06Q
48qV>Gwf
/** khrb-IY@
* @author Joa u\{ g(li-I
*/ FUjl8b-|
publicinterface UserDAO extends BaseDAO { ZUR6n>r
S.m{eur!,E
publicList getUserByName(String name)throws ps%q9}J
M)N?qRD
HibernateException; 6%Pdy$ P
0#&5.Gr)
publicint getUserCount()throws HibernateException; -[!P!d=
t&CJ%XP
publicList getUserByPage(Page page)throws D+z?wuXk
>JCM.I0_|
HibernateException; ^1aAjYFn
7-T{a<g
} 6qaQ[XTxf
$lIz{ySJv
/[)qEl2]K
Z2='o_c
ac.Ms (D
java代码: j|%HIF25
}J1tdko#
.wu
xoq
/*Created on 2005-7-15*/ /fT+^&
package com.adt.dao.impl; f[~L?B;_L
SNE#0L'}
import java.util.List; (egzH?
#K Xa&C
import org.flyware.util.page.Page; d'$T4yA
&PK\|\\2
import net.sf.hibernate.HibernateException; C
#6dC0
import net.sf.hibernate.Query; ^__Dd)(
\y)
import com.adt.dao.UserDAO; uYil ?H{kH
$8[r9L!
/** GBFtr
* @author Joa QC;^xG+W
*/ glXZZ=j
public class UserDAOImpl extends BaseDAOHibernateImpl `Ru3L#@
p>;_e(
implements UserDAO { 7{qy7,Gp
mA@Me7m}
/* (non-Javadoc) MqA`yvQm
* @see com.adt.dao.UserDAO#getUserByName v[n7"
h"[+)q%L
(java.lang.String) pdEiqLhH
*/ \VFHHi:I
publicList getUserByName(String name)throws LJTQaItdqJ
`\6?WXk3T
HibernateException { TSsKfexQ
String querySentence = "FROM user in class ~E^,=4
rzI|?QaPi
com.adt.po.User WHERE user.name=:name"; 2JS`Wqy
Query query = getSession().createQuery {?}*1,I
BMIyskl=i
(querySentence); EmT`YNuc
query.setParameter("name", name); h<\_XJJ
return query.list(); "A)("
} kY&h~Q
c$QX)V
/* (non-Javadoc) @AYo-gf
* @see com.adt.dao.UserDAO#getUserCount() C}*cx$.
*/ UYtuED
publicint getUserCount()throws HibernateException { *VkgQ`c
int count = 0; q(5+xSg"gK
String querySentence = "SELECT count(*) FROM \OpoBXh
:ECi+DxBK
user in class com.adt.po.User"; _ZAch zV
Query query = getSession().createQuery rBN)a"
9r2IuS0
(querySentence); TV}}dw
count = ((Integer)query.iterate().next .\qj;20W
DBs*Fx[
()).intValue(); oiX"Lz{
return count; {3Vk p5%l
} **[Z^$)u(
ro[Y-o5Q0
/* (non-Javadoc) =[<m[.)i
* @see com.adt.dao.UserDAO#getUserByPage N6[i{;K@N{
:b,^J&~/)1
(org.flyware.util.page.Page) ?QDWuPhN
*/ )2E%b+"
publicList getUserByPage(Page page)throws T/P7F\R
swc@34ei\
HibernateException { r
CRgzC
String querySentence = "FROM user in class VRW]a
v}v 5
com.adt.po.User"; 0X(]7b&~R
Query query = getSession().createQuery |k{-l!HI
mEuHl>
(querySentence); EC?Efc+O
query.setFirstResult(page.getBeginIndex()) V8z`qEPM
.setMaxResults(page.getEveryPage()); "MiD8wX-
return query.list(); h.whjiCFa
} !1uzX
Kb
?&l)W~S
} fj'jNE
]wuy_+$
n`;R pr&
!@
YXZ
qU[O1bN
至此,一个完整的分页程序完成。前台的只需要调用 XvSIWs
swpnuuC-
userManager.listUser(page)即可得到一个Page对象和结果集对象 YJ2ro-X
} IlP:
的综合体,而传入的参数page对象则可以由前台传入,如果用 }1%r%TikY
u=qPzmywt
webwork,甚至可以直接在配置文件中指定。 ZcryAm:I
|Zq\GA
下面给出一个webwork调用示例: <5Mrp"C[i
java代码: LN!W(n(
8kW /DcLE
o+g4p:Mf
/*Created on 2005-6-17*/ Kv+Bfh
package com.adt.action.user; ;>2#@QP
?(im+2
import java.util.List; E:VGji7s
^@}#me@
import org.apache.commons.logging.Log; {&nV4c$v
import org.apache.commons.logging.LogFactory; B[xR-6phW
import org.flyware.util.page.Page; H|+tC=]4IZ
?B4#f!X
import com.adt.bo.Result; Z|`fHO3j
import com.adt.service.UserService; ~|)
9RUXr>
import com.opensymphony.xwork.Action; U7%28#@
GFR!n1Hv
/** Y5jYmP<
* @author Joa ;1LG&h,K
*/ AQci,j"
publicclass ListUser implementsAction{ J`Oy .Qu)
t>U!Zal"
privatestaticfinal Log logger = LogFactory.getLog 3%M.U)|+
YIDg'a+z
(ListUser.class); Jqg3.2q
r69WD
.
private UserService userService; aii'}c
A!;meVUs
private Page page; 2xmT#m
uJPH~mdW
privateList users; M1uP\Sa
)Z:m)k>r;
/* Ve14rn
* (non-Javadoc) 3zb)"\(R
* kukaim>K
* @see com.opensymphony.xwork.Action#execute() *tAqt2{48
*/ tQ0=p|
T]
publicString execute()throwsException{ WLy7'3@
Result result = userService.listUser(page); {U
P_i2`.
page = result.getPage(); Y\u_+CG*
users = result.getContent(); \DyKtrnm%
return SUCCESS; n1)'cS5}
} M+UMR+K
V~c(]K)-
/** R1 qMg+
* @return Returns the page. drX4$Kdf]
*/ !47A$sQ
public Page getPage(){ di<B ~:l58
return page; *(VbPp_H_
} g _x\T+=
w#d} TY
/** 9H8=eJd
* @return Returns the users. (>r|j4$
*/ 6DO0zNTY
publicList getUsers(){ zCM^r <Kr
return users; KY8^BjY@
} j>V"hf
z,os
MS
/** TwwIt5_fN
* @param page ;HT0w_,
* The page to set. =G[H,;W
*/ M;> ha,x
publicvoid setPage(Page page){ v6KL93
this.page = page; Xv]*;Bq:SK
} i~ROQMN1
qY# m*R
/** x1:vUHwC
* @param users Fv;u1Atiw
* The users to set. *j/uihY
*/ Mn-<5 1.%
publicvoid setUsers(List users){ -uO%[/h;N
this.users = users;
:Q8g?TZ
} ?V.ig
i:\bqK
/** QZqpF9Eu
* @param userService f*UBigk
* The userService to set. fdg[{T4:
*/ !Jh*a *I}
publicvoid setUserService(UserService userService){ jg7d7{{SB
this.userService = userService; R
A*(|n>
} }FuVY><l
} DI L)7K4
yIM.j;5:~5
;CLR{t(N#V
X9p+a,
/IrKpmbq
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, UeFtzty,a
2#,8evH
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 Vj#%B.#Zbf
Y}85J:q]
么只需要: oB hL}r
java代码: -Mit$mFn
H*?U@>UU
2X&~!%-
<?xml version="1.0"?> D: NBb!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork "[q/2vC
kS%FV;9>(
1.0//EN" "http://www.opensymphony.com/xwork/xwork- p3M)gH=N
v[q2OWcL
1.0.dtd"> }3!83~Qbx
No=Ig-It
<xwork> 2G=Bav\n+
.9#4qoM'
<package name="user" extends="webwork- $6Lgaz
bN`oQ.Z 4
interceptors"> bc}U &X<
cZuZfMDM
<!-- The default interceptor stack name #I'W[\l~+
Z,M?!vK
--> tV<}!~0,*
<default-interceptor-ref
?}e8g
9OuK}Ssf
name="myDefaultWebStack"/> "WdGY*r
@NWjYHM[`
<action name="listUser" cKEf- &~
2
:u4~E3
class="com.adt.action.user.ListUser"> 16 _HO%v->
<param iNUisl
0(VH8@h`O
name="page.everyPage">10</param> TG8QT\0G
<result 6;60}y
#O6SEK|Z
name="success">/user/user_list.jsp</result> IsxPm9P2<
</action> @vh3S+=M
{mY<R`Ee
</package> 6a[D]46y,2
VT96ph
</xwork> =G]} L<
UK*+EEv
O&.^67\|
<mjH#aSy
-l+&Bkf
>d!w&0z>
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 jz
QmYcd
AR\>P
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 k!H;(B"s-
X+)68
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 M` Jj!
bAms-cXm
gRIRc4p
)_"Cz".|9
[X0Wfb}{
我写的一个用于分页的类,用了泛型了,hoho w~y+Pv@
VJJGTkm
java代码: ?`V%[~4_I
Q%KH^<
+Gqh
package com.intokr.util; }@=m[Zx#
kU$P?RD
import java.util.List; A^
$9[_
Rcs7 'q5
/** } R!-*Wk
* 用于分页的类<br> hAi50q;z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> (2(I|O#
* #x$.
* @version 0.01 $]|fjB#D
* @author cheng V9z/yNo
*/ CT+pkNC
public class Paginator<E> { c) Zid1
privateint count = 0; // 总记录数 6f,#O8]#5
privateint p = 1; // 页编号 6DqV1'
privateint num = 20; // 每页的记录数 tX$%*Uy
privateList<E> results = null; // 结果 U4qp?g+:
Sq8 `)$\
/** %>`0hk88
* 结果总数 li;Np5P
*/ jv<BGr=4;
publicint getCount(){ Bi/=cI
return count; /*!K4)$-*2
} =Y#)c]`
Bm2"} =
publicvoid setCount(int count){ NF&R}7L
this.count = count; 0][PL%3Z
} ,!_$A}@0
^
]f#ZU{A'mt
/** VeeQmR?u-
* 本结果所在的页码,从1开始 Ic/D!J{Y
* W}#eQ|oCV
* @return Returns the pageNo. \E1[ /
*/ E9TWLB5A)(
publicint getP(){ n,}\;Bp
return p; T<Y^V
} =u
W+>;]
d|CSWcU
/** pYIm43r H
* if(p<=0) p=1 Q$Qs$
* Mu$9#[/
* @param p @T[}]e
*/ mlc0XDS%
publicvoid setP(int p){ d6,SZ*AE
if(p <= 0) Y5e6|b|
p = 1; B|U*2|e
this.p = p; ee}&~%
} 5:v"^"S z
XA75tU[#
/** 0mk-o
* 每页记录数量 ,?g}->ZB
*/ "
UaUaSg#
publicint getNum(){ s{x{/Bp(KK
return num; &6
.r=,BO
} kSj,Pl\NC
|^p7:)cy
/** A (z
lX_
* if(num<1) num=1 uj#bK
7
*/ t;X
!+
publicvoid setNum(int num){ 'jh9n7mH
if(num < 1) $j=c;+W
num = 1; @%Y$@Qb{
this.num = num; _Bh-*e2k
} bV c"'RQ
2;X{ZLo
/** &("HH"!
* 获得总页数 W$&{jr-p
*/ Yzo_ZvL
publicint getPageNum(){ $OEhdz&Fi
return(count - 1) / num + 1; PNVYW?l
} (
-^-
$&D$Uc`U>
/** ;Z:zL^rvn
* 获得本页的开始编号,为 (p-1)*num+1 w}2 ;f=
*/ 8K(3{\J[V
publicint getStart(){ 5X"y46i,H
return(p - 1) * num + 1; fePt[U)2
} ]M2<b:yo
|ci1P[y
/** *\W
*,D.I
* @return Returns the results. ^\|Hz\"*
*/ ;&="aD
publicList<E> getResults(){ B#Sg:L9Tr'
return results; _g{*;?mS
} 08*O|Ym,
)1de<# qM
public void setResults(List<E> results){ "^?|=sQ
this.results = results; FUy!j|W6f
} c;RB!`9"
[+7 Nu
public String toString(){ *c"tW8uR
StringBuilder buff = new StringBuilder
-w7g}
AH?T}t2
(); #p<1@,
buff.append("{"); SU.9;I
!
buff.append("count:").append(count); a+wc"RQ
|
buff.append(",p:").append(p); s+mNr3
buff.append(",nump:").append(num); 6:PQkr
buff.append(",results:").append ulY8$jB
P?- #d\qi
(results); Lye^G%{
buff.append("}"); dMo456L
return buff.toString(); 3em&7QM
} "
3ryp
A
O$<m(~[S
} +M@,CbqD
TR@*tfS
t0^chlJP$