Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 M\?uDC9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?<yq 2`\4O
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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 n"<GJ.{
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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 4z0R\tjT
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分页支持类: bUAR<R'E
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java代码: X@h^T>["
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package com.javaeye.common.util; \A3>c|
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import java.util.List; THbtu*El
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publicclass PaginationSupport { Gkodk[VuLs
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publicfinalstaticint PAGESIZE = 30; b!^M}s6
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privateint pageSize = PAGESIZE; %+7T9>+
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privateList items; ZXsY-5$#d-
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privateint totalCount; =~W0 ~lxX
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privateint[] indexes = newint[0]; RP|>&I
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privateint startIndex = 0; 1 ~B<
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public PaginationSupport(List items, int FUzMc1zy|
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totalCount){ 6L:trLuQ
setPageSize(PAGESIZE); h[-d1bKwS
setTotalCount(totalCount); \%-E"[!
setItems(items); bU:}ZO^S
setStartIndex(0); z3vsz
} oXQ<9t1(
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public PaginationSupport(List items, int M ~ i+F0
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totalCount, int startIndex){ k binf
setPageSize(PAGESIZE); Re kb?|{z
setTotalCount(totalCount); /+x#V!zM
setItems(items); wzDk{4U
setStartIndex(startIndex); 6HEqm>Yau
} Ha=_u+@
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public PaginationSupport(List items, int }:RT,<
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totalCount, int pageSize, int startIndex){ ]8xc?*i8
setPageSize(pageSize); ElEv(>G*
setTotalCount(totalCount); #LN5&i;s
setItems(items); Z92iil;t
setStartIndex(startIndex); ~|r'2V*
} O ':0V
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publicList getItems(){ =.qm8+
return items; Hyq@O8
} 't0+:o">:
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publicvoid setItems(List items){ Xx3g3P
this.items = items; #K:-Bys5v
} qLQ <1>u
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publicint getPageSize(){ BrlzN='j}
return pageSize; q3AJwELXw
} n*vTVt)dJ
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publicvoid setPageSize(int pageSize){ fr}1_0DDz
this.pageSize = pageSize; ,?xLT2>J_
} 7xv4E<r2
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publicint getTotalCount(){ `2xH7a-
return totalCount; {)
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}
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publicvoid setTotalCount(int totalCount){ b!'l\~`{i
if(totalCount > 0){
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this.totalCount = totalCount; biK)&6|`sa
int count = totalCount / fBf4]^
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pageSize; &v5G92
if(totalCount % pageSize > 0) P"(z jG9-
count++; heE}_,$|
indexes = newint[count]; ia%z+:G
for(int i = 0; i < count; i++){ 8)^B32
indexes = pageSize * F_A%8)N
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} YG0Px Zmi
}else{ 7|&e[@B
this.totalCount = 0; X,C*qw@
} B :.@Qi^
} _BZ1Vnv
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publicint[] getIndexes(){ kzZDtI)
return indexes; q"gqO%Wb|
} qP~WEcH`[
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publicvoid setIndexes(int[] indexes){ G'ij?^?
this.indexes = indexes; A}t %;V2
} NFk}3w:
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publicint getStartIndex(){ 403[oOj
return startIndex; {>8Pl2J
} z%(Fo2)^
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publicvoid setStartIndex(int startIndex){ &+mV7o
if(totalCount <= 0) V]79vC
this.startIndex = 0; aWyUu/g<A`
elseif(startIndex >= totalCount) $4Z+F#mx
this.startIndex = indexes di~]HUZh)
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[indexes.length - 1]; IByf_E;r
elseif(startIndex < 0) _fcS>/<a
this.startIndex = 0; "j{i,&Y$_
else{ nz4<pvC,*
this.startIndex = indexes *IC^IC:
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[startIndex / pageSize]; ')B =|T)
} >T<6fpXuk2
} \|CPR6I
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publicint getNextIndex(){ y|$R`P
int nextIndex = getStartIndex() + tawe Gc%~
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pageSize; KQ&Y2l1*>>
if(nextIndex >= totalCount) \ht ?Gn
return getStartIndex(); otO
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else qAoAUDm
return nextIndex; 'T\dkSJv;V
} B[r<m J
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publicint getPreviousIndex(){ > 2#%$lX6
int previousIndex = getStartIndex() - n-DaX
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pageSize; JIzY,%`\
if(previousIndex < 0) }91*4@B7
return0; }g~g50ci
else Kx~$Bor_!
return previousIndex; ZWO)tVw9G
} 11@]d]v ,
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} Fh K&@@_
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抽象业务类 +b^]Pz5
java代码: aX;A==>
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/** YutQ ]zYA.
* Created on 2005-7-12 @5xu>g Kn
*/ (Yv{{mIy
package com.javaeye.common.business; iv*V#J>
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import java.io.Serializable; ;f:gX`"\
import java.util.List; +Mk#9r
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import org.hibernate.Criteria; l<(cd,
import org.hibernate.HibernateException; > !L&>OOx
import org.hibernate.Session; HTV ~ ?E
import org.hibernate.criterion.DetachedCriteria; H3, ut
import org.hibernate.criterion.Projections; 8-m
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import `\bT'~P
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org.springframework.orm.hibernate3.HibernateCallback; W^es;5
import VPt9QL(
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org.springframework.orm.hibernate3.support.HibernateDaoS yEq#Dr
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upport; 8TE>IPjm
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import com.javaeye.common.util.PaginationSupport; ]IZ>2!6r
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public abstract class AbstractManager extends =7%oE[
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HibernateDaoSupport { w&Y{1r F>
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privateboolean cacheQueries = false; 3uV4/%U
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privateString queryCacheRegion; 8Hi!kc;f6>
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publicvoid setCacheQueries(boolean %y&]'A
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cacheQueries){ 87V1#U ^
this.cacheQueries = cacheQueries; UL(
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} {hQ6K)s
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publicvoid setQueryCacheRegion(String <xo-Fv
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queryCacheRegion){ 06 i;T~Y
this.queryCacheRegion = TW7:q83{l
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queryCacheRegion; 1D F/6y
} >xqM5#m`E$
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publicvoid save(finalObject entity){ c0_E_~
getHibernateTemplate().save(entity); V5mlJml2(
} e$e#NoN
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publicvoid persist(finalObject entity){ ['q&@_d7
getHibernateTemplate().save(entity); c3)C{9T](
} AQss4[\Dx
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publicvoid update(finalObject entity){ u,1}h L
getHibernateTemplate().update(entity); +/rH(Ni
} ,qQG;w,m
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publicvoid delete(finalObject entity){ k`\R+WK$
getHibernateTemplate().delete(entity); ]ikomCg
} "Pz}@=
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publicObject load(finalClass entity, 8z2Rry
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finalSerializable id){ usFfMF X
return getHibernateTemplate().load F%d\~Vj
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(entity, id); 80pid[F
} C3'rtY.
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publicObject get(finalClass entity, +GF#?X0^
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finalSerializable id){ $w#r"= )
return getHibernateTemplate().get mee$"Y
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(entity, id); -nbMTY}
} 5fJ[}~
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publicList findAll(finalClass entity){ UPiW73Nu
return getHibernateTemplate().find("from ,=QM#l]
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" + entity.getName()); 8RW&r
} V\]" }V)"
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publicList findByNamedQuery(finalString /)
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namedQuery){ Wg`AZ=t
return getHibernateTemplate tK(g-u0N`(
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().findByNamedQuery(namedQuery); c{+A J8
} }8-\A7T
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publicList findByNamedQuery(finalString query, Iu@y(wyg
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finalObject parameter){ SqA
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return getHibernateTemplate errH>D~
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().findByNamedQuery(query, parameter); DZS]AC*
} BYrZEVM9
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publicList findByNamedQuery(finalString query, !y:%0{l
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finalObject[] parameters){ |RkcDrB~
return getHibernateTemplate ~ PWSo%W8
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().findByNamedQuery(query, parameters); i_Re*
} 4Y> Yi*n
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publicList find(finalString query){ Ny- [9S-<
return getHibernateTemplate().find ;<
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(query); G!N{NCq
} I){\0vb@
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publicList find(finalString query, finalObject JA)?p{j
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parameter){ z4#(Ze@u~_
return getHibernateTemplate().find ?~"bR%
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(query, parameter); f/,>%j=Ms
} _@mRb^
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public PaginationSupport findPageByCriteria j(:I7%3&(*
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(final DetachedCriteria detachedCriteria){ 6VP`evan
return findPageByCriteria %@a8P
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); F~:O.$f]G
} ?3ig)J,e[
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public PaginationSupport findPageByCriteria 0Sq][W=
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(final DetachedCriteria detachedCriteria, finalint X,aYK;q%z
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startIndex){ U[L9*=P;
return findPageByCriteria RO;Bl:x4
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(detachedCriteria, PaginationSupport.PAGESIZE, ,;?S\V
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startIndex); ?"#%SKm
} YJg,B\z}
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public PaginationSupport findPageByCriteria n+@F`]Ke
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(final DetachedCriteria detachedCriteria, finalint &AVpLf:?
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pageSize, wbDM5%
finalint startIndex){ FLg*R/
return(PaginationSupport) )#|<w9uec
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getHibernateTemplate().execute(new HibernateCallback(){ ;*ix~taL%
publicObject doInHibernate '7wd$rl
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(Session session)throws HibernateException { ah
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Criteria criteria = JO=[YoTr
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detachedCriteria.getExecutableCriteria(session); :j|IP)-f
int totalCount = gqXS~K9t
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((Integer) criteria.setProjection(Projections.rowCount j'[m:/
^ -FX
()).uniqueResult()).intValue(); gBT2)2]
criteria.setProjection 7 n]65].t
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(null); 8[r9HC
List items = )jWOP,|
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criteria.setFirstResult(startIndex).setMaxResults O }9KJU
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(pageSize).list(); 3nT
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PaginationSupport ps = \s3]_1F;t
*
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new PaginationSupport(items, totalCount, pageSize, JN^&S
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startIndex); +`7KSwa
return ps; !O\;Nua
} N#lDW~e'
}, true); '$4O!YI9@
} e%8|<g+n6
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public List findAllByCriteria(final 0 a]/%y3V
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DetachedCriteria detachedCriteria){ QL6C,#6
return(List) getHibernateTemplate LjL[V'JL
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().execute(new HibernateCallback(){ {`2R,Jb%S
publicObject doInHibernate E?(xb B
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(Session session)throws HibernateException { 85EQ5yY
Criteria criteria = #%J5\+ua
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detachedCriteria.getExecutableCriteria(session); $$:ZX
return criteria.list(); $/6;9d^
} BCe_@
}, true); G'YH6x,
} ARcv;H 5
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public int getCountByCriteria(final u77E! z4Uz
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DetachedCriteria detachedCriteria){ s1|/S\
Integer count = (Integer) >~`C-K#
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getHibernateTemplate().execute(new HibernateCallback(){ M#|dIbns
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publicObject doInHibernate _gKe%J&
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(Session session)throws HibernateException { Hw#d_P:
Criteria criteria = Sa19q.~%
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detachedCriteria.getExecutableCriteria(session); :xKcpY[{
return Y>jiXl?&
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criteria.setProjection(Projections.rowCount 5*[2yKsTi
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()).uniqueResult(); O;7)Hjw t
} f|u#2!7
}, true); [AV4m
return count.intValue(); eNiaM6(J
} jA#/Z
} [r/k% <
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用户在web层构造查询条件detachedCriteria,和可选的 fDx9iHGv
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 eT2*W$
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PaginationSupport的实例ps。 Scv#zuv_
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ps.getItems()得到已分页好的结果集 "`6n6r42
ps.getIndexes()得到分页索引的数组 (H+'X}1
ps.getTotalCount()得到总结果数 Zo>]rKeV
ps.getStartIndex()当前分页索引 <AJ97MLcc
ps.getNextIndex()下一页索引 tGB@$UmfU
ps.getPreviousIndex()上一页索引 HHqwq.zIy
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0a"igq9t
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 r,_?F7
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一下代码重构了。 4Vq%N
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我把原本我的做法也提供出来供大家讨论吧: :x_'i_w
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首先,为了实现分页查询,我封装了一个Page类: eW|^tH
java代码: %4HRW;IU
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/*Created on 2005-4-14*/ 1
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package org.flyware.util.page; :kfp_o+J
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/** "kZ[N'z(
* @author Joa +MmHu6"1
* b%cF
*/ 1yqJwy;X
publicclass Page { +VQ\mA59
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/** imply if the page has previous page */ =_0UD{"_0
privateboolean hasPrePage; )Wb0u0)_
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/** imply if the page has next page */ | [>UH
privateboolean hasNextPage; S8e{K
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/** the number of every page */ [V:\\$
privateint everyPage; 2k<;R':
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/** the total page number */ |r bWYl.b
privateint totalPage; {/pm<k=
;NRF=d>
/** the number of current page */ *{+G=d
privateint currentPage; .CFa9"<
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/** the begin index of the records by the current "?mJqA
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query */ 4 {9B9={
privateint beginIndex; M`S0u~#tI
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/** The default constructor */ V\6]n2
public Page(){ t]Xw{)T
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} &?h,7
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/** construct the page by everyPage Ag@;
* @param everyPage _SA5e3#
* */ cp o-.
public Page(int everyPage){ U)3DQ6T99
this.everyPage = everyPage; fNrgdfo
} R i^[i}
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/** The whole constructor */ i E CrI3s
public Page(boolean hasPrePage, boolean hasNextPage, ~/*MY
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int everyPage, int totalPage, &d|r~NhP
int currentPage, int beginIndex){ (64yg
this.hasPrePage = hasPrePage; !fj(tPq
this.hasNextPage = hasNextPage; ZI=v.wa
this.everyPage = everyPage; <ZB1Vi9}8
this.totalPage = totalPage; -I=l8m6L
this.currentPage = currentPage; !>1@HH?I\/
this.beginIndex = beginIndex; E4hLtc^
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} 5<w g8y
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/** 6&/T@LQYrh
* @return RZ+`T+zL
* Returns the beginIndex. p QizJ6
*/ o*J3C>
publicint getBeginIndex(){ )wNP(
@$L
return beginIndex; H<3I 5Kgt
} 9V5-%Iv
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/** 8Ac:_Zg
* @param beginIndex Q1+dCCY#F
* The beginIndex to set. v;)..X30
*/ @9"J|}
publicvoid setBeginIndex(int beginIndex){ y:6; LZ9[
this.beginIndex = beginIndex; H*)NLp
} ]9@F~)
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/** =W'Ae,&
* @return r-<F5<H+K@
* Returns the currentPage. & \f{E\A#
*/ $*?,#ta
publicint getCurrentPage(){ )6aAB|
return currentPage; f`Fi#EKT
} ZMq6/G*fD
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/** ,S!azN=
* @param currentPage O6OP =K!t:
* The currentPage to set. F|!){=
*/ 1@-Ns
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; rh^mJUh
} r3PT1'P?L
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/** LSRk7'0
* @return o !U
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* Returns the everyPage. 7"C$pm6
*/ j}C}:\-fY
publicint getEveryPage(){ Ct>GYk$
return everyPage; UNBH
} mrjswF27$o
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/** _D+J!f^
* @param everyPage X93!bB
* The everyPage to set. r!
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*/ N}t
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publicvoid setEveryPage(int everyPage){ Ll4g[8
this.everyPage = everyPage; 5bgs*.s
} - RU=z!{
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/** S@/IQR
* @return a5TioQ
* Returns the hasNextPage. ~5oPpTAe
*/ NN?`"Fww
publicboolean getHasNextPage(){ gp\<p-}
return hasNextPage; .~7FyLl$
} ?)ONf#4Y
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/** M"94#.dKK
* @param hasNextPage v
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* The hasNextPage to set. U3dwI:cG
*/ K>@+m
publicvoid setHasNextPage(boolean hasNextPage){ Ptdpj)oi&Q
this.hasNextPage = hasNextPage; e(<str>
} [wzb<"kW
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/** ZG&>:Si;
* @return mmk=97
* Returns the hasPrePage. #iHs*
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*/ Ev}C<zk*
publicboolean getHasPrePage(){ TJR:vr
return hasPrePage; fNW"+ <W
} (O(}p~s
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/** SR|`!
* @param hasPrePage @/ohg0
* The hasPrePage to set. P&^;656r
*/ JAem0jPC8
publicvoid setHasPrePage(boolean hasPrePage){ yL-YzF2
this.hasPrePage = hasPrePage; G\+L~t
} y#z
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/** (bH`x]h#
* @return Returns the totalPage. VL` z[|e @
* ia+oX~W!VR
*/ HK0!P*
publicint getTotalPage(){ YOmM=X+'H
return totalPage; SS WP~
t
} :x4|X8>
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/** !`Hd-&}bYz
* @param totalPage fy@<&U5rg
* The totalPage to set. J`].:IOh
*/ oUQ,61H
publicvoid setTotalPage(int totalPage){ ^Xq 6:
this.totalPage = totalPage; %UERc{~o*,
} 1oWED*B
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} $m-2HhqZ
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9 %I?).5
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 CU@Rob} s
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个PageUtil,负责对Page对象进行构造: 67G?K;)e
java代码: (jRm[7H
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/*Created on 2005-4-14*/ QLiu2U o
package org.flyware.util.page; '6cWS'9"
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import org.apache.commons.logging.Log; pUQ/03dp
import org.apache.commons.logging.LogFactory;
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/** zkuU5O
* @author Joa eo?;`7
* o.!~8mD
*/ 7`zHX&-W
publicclass PageUtil { ?IqQ-C)6D
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privatestaticfinal Log logger = LogFactory.getLog ogHCt{'
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(PageUtil.class); v50bdj9}k
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/** bB1UZ O
* Use the origin page to create a new page Vr`R>S,-
* @param page NflD/q/ L
* @param totalRecords \F/hMXDlJ
* @return x7!L{(E3
*/ %\dz
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publicstatic Page createPage(Page page, int d"*uBVzXm
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totalRecords){ O7-mT8o
return createPage(page.getEveryPage(), q1"$<# t
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page.getCurrentPage(), totalRecords); 1Z+8r
} W14
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/** >,$_| C
* the basic page utils not including exception i1NY9br
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handler r%yvOF\>
* @param everyPage ~=6xyc/c
* @param currentPage +eK"-u~K
* @param totalRecords aW)-?(6>
* @return page jET{Le8i
*/ >~[c|ffyo/
publicstatic Page createPage(int everyPage, int H8Bs<2
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currentPage, int totalRecords){ (:TjoXXiY
everyPage = getEveryPage(everyPage); DEG[Z7Ju
currentPage = getCurrentPage(currentPage); M "p
int beginIndex = getBeginIndex(everyPage, *`ua'"="k
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currentPage); )_syZ1j
int totalPage = getTotalPage(everyPage, ; >hNt
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totalRecords); .w=/+TA
boolean hasNextPage = hasNextPage(currentPage, r~jm`y
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totalPage); PV'x+bN5
boolean hasPrePage = hasPrePage(currentPage); 4sF"6+%5d
m? J0i>H
returnnew Page(hasPrePage, hasNextPage, 4o
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everyPage, totalPage, u~7hWiY<2
currentPage, H]{v;;'~
C*)3e*T*
beginIndex); GP!?^r:en
} ^84G%)`&
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privatestaticint getEveryPage(int everyPage){ EUD~CZhS"k
return everyPage == 0 ? 10 : everyPage; ,
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} %p^wZtm
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privatestaticint getCurrentPage(int currentPage){ M -cTRd-i
return currentPage == 0 ? 1 : currentPage; `w#Oih!6A|
} v5!d$Vctu
2&:f&"
privatestaticint getBeginIndex(int everyPage, int h)ECf?r<
QRc{vUR&
currentPage){ =9y[1t
return(currentPage - 1) * everyPage; ?26I,:;
} A!s`[2 Z
jSh5!6O
privatestaticint getTotalPage(int everyPage, int ddJQC|xR}
Cc+t}"^
totalRecords){ l2zFKCGF(
int totalPage = 0; @Owb?(6?
we~[ ]
\
if(totalRecords % everyPage == 0) :q$.,EZ4#n
totalPage = totalRecords / everyPage; V)Z}En["1
else >Wm`v.-
totalPage = totalRecords / everyPage + 1 ; q8X feoUV
Y;dz,}re
return totalPage; 2iY3Lsna
} [YRz*5
#|Y5,a,{
privatestaticboolean hasPrePage(int currentPage){ ][gq#Vx@
return currentPage == 1 ? false : true; \\r)Ue]
} 2Nu=/tMN
"Gfh ,e
privatestaticboolean hasNextPage(int currentPage, 1L%CJ+Q#0i
{C 6=[
int totalPage){ 8{wwd:6
return currentPage == totalPage || totalPage == mq aHwID
Tzt8h\Q^z
0 ? false : true; -[*,^Ti`
} c(3~0Yr
&oP+$;Y
3EV;LH L
} k$R~R-'
~Sg5:T3
R@58*c:U(
wj*,U~syB
Jj>?GAir
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。 NO7J!k?
+6sy-<ZL:
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 Ed0QQyC@9
_(_a*ml
做法如下: Sz%tJD..
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 **w!CaqvY
(yu/l6[
的信息,和一个结果集List: ' KWyx
java代码: ;+W#5<i
u!!Y=!y*<
oz,np@f)J
/*Created on 2005-6-13*/ Jv>gwV{
package com.adt.bo; j#X.KM
s[M?as
import java.util.List; a=1NED'
N+m)/x
=:
import org.flyware.util.page.Page; nGpXI\K
T}Km?d
/** X\]L=>]C
* @author Joa l Q'I
*/ Pj#<K%Bz
publicclass Result { Gy9$wH@8
X\`_3=
private Page page; |8&,b`Gfo
:Ux?,
private List content; X^T:8npxt
(X $=Q6
/** %zA;+s$l
* The default constructor "9m2/D`=
*/ sNj)ZWgd>
public Result(){ 3*]eigi)
super(); *S]Ci\{_
} 4iqoR$3Fc
LIS)(X<]?
/** 9 %8"e>~
* The constructor using fields *EOdEFsR/
* na#CpS;pc
* @param page qIVx9jNN
* @param content -l`f)0{
*/ "oTHq]Ku
public Result(Page page, List content){ vL|SY_:4
this.page = page; Keuf9u
this.content = content; di?K"Z>
} G^~k)6v=m
x^HGVWw_
/** D2<fw#
* @return Returns the content. ^"VJd[Hn
*/ W}3.E "K
publicList getContent(){ "8c@sHk(w
return content; "w^!/
} xe#FUS
3
yyoqX"v[
/** nc~F_i=
* @return Returns the page. s:OFVlC%\
*/ o}$XH,-9&
public Page getPage(){ aK&b{d
return page; j K!Au
} FemCLvu
NiWa7 /Hr
/** ;'?l$
._
* @param content G,$PV
e*
* The content to set. z{[xze-f
*/ W0(_~
public void setContent(List content){ <A[E:*`*
this.content = content; ~"!]
3C,L
} AuUde$l_
Y,GU%[+
/** _p#CwExuy
* @param page CKtB-a
* The page to set. &+a9+y
*/ Fw/6?:C}O6
publicvoid setPage(Page page){ C+?Hm1
this.page = page; 1LqoF{S:
} 6o
|kIBte-
} {G|,\O1
[DJ flCR&
?Eg(Gu.J
Q~814P8]
x4g3rmp
2. 编写业务逻辑接口,并实现它(UserManager, NS9B[*"Jl
wHsYF`
UserManagerImpl) 3Vsc 9B"w
java代码: #hW;Ju73
sSOOXdnGG
8yRJD[/S
/*Created on 2005-7-15*/ r>dwDBE
package com.adt.service; _9faBrzd
f_wvZ&
import net.sf.hibernate.HibernateException; *"R|4"uy
2Gz}T _e
import org.flyware.util.page.Page; * 1T&
;>506jZ
import com.adt.bo.Result; XOxr?NPQ^
vbkI^+=,YY
/** z3`-plE
* @author Joa 4FEk5D
*/ ?f#y1m
publicinterface UserManager { n?A6u\sQ
+~'865 {
public Result listUser(Page page)throws ICuF %
P1zKsY,l$<
HibernateException; rW0kA1=E
3j,Q`+l/6d
} A54N\x,
Dakoqke
V7GRA#|
flk=>h|
rE iKi
java代码: ~oI1zNz/
n/DP>U$I&
<!L>Exh&r
/*Created on 2005-7-15*/ m/v9!'cMI
package com.adt.service.impl; /4t j3B,
"XB[|#&
import java.util.List; 0rh]]kj
|w_7_J2
import net.sf.hibernate.HibernateException; WEFlV4/
0="%Y^N
import org.flyware.util.page.Page; &?VQ,+[<
import org.flyware.util.page.PageUtil; tDSJpW'd
kV?y0J.
import com.adt.bo.Result; anIAM
import com.adt.dao.UserDAO; E8>Rui@9
import com.adt.exception.ObjectNotFoundException; >^%7@i:@U
import com.adt.service.UserManager; 0%,!jW{`
"vXxv'0\f
/** #rxVd
7f
* @author Joa RD\
*/ km)zMoE{c{
publicclass UserManagerImpl implements UserManager { zfI>qJ+Nqt
8'~[pMn`
private UserDAO userDAO; UjaK&K+M?
6Pnk5ps }h
/** < XP9@t&
* @param userDAO The userDAO to set. ' pm2n0
*/ m6n?bEl6I
publicvoid setUserDAO(UserDAO userDAO){ wm]^3qI2
this.userDAO = userDAO; d_4T}%q
} Vm%1> '&
$P>`m$(8
/* (non-Javadoc) ${+ @gJ+S
* @see com.adt.service.UserManager#listUser cU0s
p
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(org.flyware.util.page.Page) cj+ FRG~u
*/ i%ZW3MrY~
public Result listUser(Page page)throws 9&upujVS
f&}k^>N#3
HibernateException, ObjectNotFoundException { +SsK21f"r
int totalRecords = userDAO.getUserCount(); |o,8V p
if(totalRecords == 0) +# GQ,
throw new ObjectNotFoundException =g/{%;
k9$K}
("userNotExist"); Mzsfo;kk+
page = PageUtil.createPage(page, totalRecords); =3q/F7-
List users = userDAO.getUserByPage(page); mu?Eco`~
returnnew Result(page, users); )p
T?/J
} 7s"<
'cx_F
VS9`{
} 3BB%Z6F
D!.[q -<
A'G66ei
"
Om[~-31
wB.Nn/p
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +6UVn\9Q
cs T2B[f9D
询,接下来编写UserDAO的代码: $rz=6h
3. UserDAO 和 UserDAOImpl: ':gUOra|I
java代码: fQ/
0R
qY~`8
x
=0^Ruh
/*Created on 2005-7-15*/ HFwN
package com.adt.dao; BDVHol*g
]?3un!o3o
import java.util.List; zXv3:uRp.
e_s&L,ze
import org.flyware.util.page.Page; AFc$%\s4
0TN;86Mo
import net.sf.hibernate.HibernateException; p[<Dk$7K
QFg sq{
/** 0GB:GBhZ
* @author Joa
=i_-F$pV
*/ |AcRIq
publicinterface UserDAO extends BaseDAO { fRy^Q_~,
-:30:oq
publicList getUserByName(String name)throws ~n[xtWO0
ox:[f9.5
HibernateException;
Vm(1G8 a
GDu~d<R H
publicint getUserCount()throws HibernateException; 2R=DB`3
bhkUKxd
publicList getUserByPage(Page page)throws Lg~B'd8m
IB#
@yH
HibernateException; =
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Y^
kXSU
} vFE;D@bz:
v-yde>(
}e2(T
PUo/J~ v
p3]_}Y
D[#
java代码: #+$G=pS'v
?*?RP)V
VYt!U
/*Created on 2005-7-15*/ sXi=70o
package com.adt.dao.impl; }-~X4u#
yHHt(GM|o
import java.util.List; #{k|I$
eFpTW&9n
import org.flyware.util.page.Page; [%9noB
MF~H"D
n
import net.sf.hibernate.HibernateException; (q{Ck#+
import net.sf.hibernate.Query; LbaK={tR
@;<ht c
import com.adt.dao.UserDAO; jV?
}9L^;
PQK(0iCo4
/** k]5Bykf`Ky
* @author Joa z;A>9vQ_J
*/ Vs%|pIV
public class UserDAOImpl extends BaseDAOHibernateImpl QmLF[\Oo_
.A-]_98Z
implements UserDAO { 6U[4%(
;QW3CEaUq
/* (non-Javadoc) 0Z0:,!
* @see com.adt.dao.UserDAO#getUserByName 8zA=;~GHP
?;vgUO
(java.lang.String) uL3Eq>~x
*/ " R-!(9k^`
publicList getUserByName(String name)throws io#&o;M<
TjHwjRa
HibernateException { ,0E{h}(
String querySentence = "FROM user in class ZQ_xDKqRV
3}@_hS"^8
com.adt.po.User WHERE user.name=:name"; iC W*]U
Query query = getSession().createQuery d?:=PH
a@\D$#2r
(querySentence); Pu"R,a
query.setParameter("name", name); ow0!%|fO
return query.list(); rS4@1`/R
} vG;zJ#c
AC;V
m: @{
/* (non-Javadoc) u0#}9UKQ
* @see com.adt.dao.UserDAO#getUserCount() VQ0fS!5'
*/ q EP
4
publicint getUserCount()throws HibernateException { L0&RvI#
int count = 0; u%]shm
String querySentence = "SELECT count(*) FROM 2gzou|Y
cs1l~bl
user in class com.adt.po.User"; 6ezS {Q
Query query = getSession().createQuery l5g$vh\aQ]
1j:Wh
(querySentence); *^RmjW1I
count = ((Integer)query.iterate().next MXzVgy
"y_#7K
()).intValue(); [5uRS}!
return count; HcedE3Rg
} /[ 6j)HIS
jS+AGE?5e
/* (non-Javadoc) s/7 A7![
* @see com.adt.dao.UserDAO#getUserByPage d3W0-INL
9*E7}b,
(org.flyware.util.page.Page) txcf=)@>V
*/ g8w2Vz2/
publicList getUserByPage(Page page)throws )ZBY* lk9
_UT$,0u_i
HibernateException { ^2$ lJ
String querySentence = "FROM user in class ^=:9)CNw(
*;m5'}jsy
com.adt.po.User"; :.?gHF.?
Query query = getSession().createQuery om |"S
t=u
Qb=
(querySentence); ?gPKcjgoH!
query.setFirstResult(page.getBeginIndex()) Q}!mx7b0]
.setMaxResults(page.getEveryPage()); $uap8nN
return query.list(); #7ov#_2Jd
} 63.wL0~
c\ia6[3sX
} B 9T!j]'
Rb%%?*|
Hewd4k
RPIyO
,SQZD,3v4
至此,一个完整的分页程序完成。前台的只需要调用 YKbaf(K)9
P%#*-zCCx
userManager.listUser(page)即可得到一个Page对象和结果集对象 'Fs)Rx}\0
KAsS[
的综合体,而传入的参数page对象则可以由前台传入,如果用 *1 G>YH
p_UlK8rb
webwork,甚至可以直接在配置文件中指定。 @&]#uRl|[
m85WA
#
`
下面给出一个webwork调用示例: ?x+Z)`w_
java代码: O/.Uh`T`6
*dvDap|8W
8a_[B~
/*Created on 2005-6-17*/ v3GwD00
package com.adt.action.user; {
.*y
uP<0WCN
import java.util.List; WHAQu]{
gqR)IVk>%
import org.apache.commons.logging.Log; >@YtDl8R
import org.apache.commons.logging.LogFactory; 0<8XI>.3D
import org.flyware.util.page.Page; UjOB98Du
}?&k a$rI
import com.adt.bo.Result; Y!WG)u5
import com.adt.service.UserService; ,R$u?c0>'&
import com.opensymphony.xwork.Action; <H0R&l\
`'\t$nU
/** `xz<>g9e
* @author Joa /
}R z=&
*/ Qfky_5R\
publicclass ListUser implementsAction{ T]j.=|,d
Wd0[%`dq
privatestaticfinal Log logger = LogFactory.getLog Yp0/Ab(v
%0 #XPc("
(ListUser.class); r?CI)Y;
McoK@q;
private UserService userService; ~GuMlV8
8)kLV_+%
private Page page; 'S[++w?Qq
RJy=pNztm
privateList users; VR
ltkI}h,e
/* S}f?.7
* (non-Javadoc) =CL}
$_
* 1yV: qp
* @see com.opensymphony.xwork.Action#execute() wZ4tCZA
*/ sz @p_Z/
publicString execute()throwsException{ A<\JQ
Result result = userService.listUser(page); A/7X9ir
page = result.getPage(); (_4;') 9
users = result.getContent(); H"Klj_<dH0
return SUCCESS; tX!nsm1
} *xE,sj+(
hoT/KWD,
/** .))v0
* @return Returns the page. +525{Tj
*/ @Kf_z5tm:
public Page getPage(){ hLDA]s
return page; XyMG.r-,
} x!_<z''
4lqH8l.
/** QZX~T|Ckv
* @return Returns the users. BS&;n
*/ Cda!Mk:
publicList getUsers(){ |v[ Rp=?]
return users; P/JK $nb
} l88A=iLgv
kD) $2I?
/** }pa9%BQI
* @param page 4d_s%n?C
* The page to set. l;sy0S"DO]
*/ Bm\qxQ
publicvoid setPage(Page page){ _5MNMVLwW
this.page = page; \v6M:KR5/
} l%Gw_0.?e
AF43$6KZP$
/** 5'w^@Rs5
* @param users /%4_-C pm
* The users to set. 5j0{p$'9
*/ W23]Bx
publicvoid setUsers(List users){ SEl#FWR
this.users = users; n,~;x@=5
} !GW,\y
aZKOY
/** r-kMLw/)
* @param userService PY3ps2^K.
* The userService to set. >/<:Q &
*/ v(leide
publicvoid setUserService(UserService userService){ 6DL[aD
this.userService = userService; ES<{4<Kpx
} W>M~Sk$v
} VD4C::J
7ZUiY
dY"}\v6
$|KaBx1
;NV'W]
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, L:M0pk{T
V@d)?T
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 PuxK?bwC
k>E`s<3
么只需要: |3K)$.6~
java代码: .$",
*d
yMLOUUWa8x
>QHo@Zqj(
<?xml version="1.0"?> Gg\G'QU
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork XT,#g-oi
7ou46v|m5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- VGw(6`|!
M}DH5H"s
1.0.dtd"> @c'|Iqy`
.bf<<+'o
<xwork> JK#vkCkyM
Ufo>|A6;$
<package name="user" extends="webwork- 5FC4@Ms`
2JmZ{
interceptors"> 1\dn1Hh
4gdY`}8b^}
<!-- The default interceptor stack name /w]&t\]*
bg?"ILpk
--> I\\QS.2
<default-interceptor-ref FVF-:C
8*g ^o\M
name="myDefaultWebStack"/> t ]c{c#N/
-~)OF
<action name="listUser" +Ra3bj l
L;W.pe0
class="com.adt.action.user.ListUser"> ql5x2n
<param OMihXt[
Uz%Z&K
name="page.everyPage">10</param> I~'*$l
<result ZX
b}91rzt
-Uo?WXP]B'
name="success">/user/user_list.jsp</result> o@lWBfB*%e
</action> 1u]P4Gf=
,]Zp+>{
</package> }8'&r(cN4
|0bc$ZY:
</xwork> 2aw&F Z?
,/&Zw01dGN
}tST)=M`
^T4Ay=~{
;52'}%5
Jf:,y~mV
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 +rNkN:/L
H L<s@kEZ
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。 tn/T6C^)
<XQ.A3SG!
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 HTz+K6&
c\cZ]RZ
MM{_Ur7Q
]*%+H|l
f?Bj _z
我写的一个用于分页的类,用了泛型了,hoho 1
[z'G)v
i cUT<@0
java代码: :ipoD%@
j?(!^ _!m
0?bA$y
package com.intokr.util; 9w;?-
5b#QYu
import java.util.List; us)*2`?6t
,[48Mspp
/** H!IDV}dn
* 用于分页的类<br> %4>x!{jwV
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~hN~>0O
* c"gsB!xh
* @version 0.01 00vBpsZj2;
* @author cheng "c`xH@D
*/ xc'vS>&
public class Paginator<E> { 1H4fJ3-
privateint count = 0; // 总记录数 h.tY 'F
privateint p = 1; // 页编号 Q]JX`HgPaU
privateint num = 20; // 每页的记录数 &hZwZgV+3
privateList<E> results = null; // 结果 B(HT.%r^A
<"&'>?8j
/** t
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* 结果总数 oJ;rc{n-
*/ 0.(<'!"y
publicint getCount(){ Z/ bB
h
return count; utO.WfWP
} X} JOX9pK
KI&:9j+M)
publicvoid setCount(int count){ *FgJ|y6gk
this.count = count; CyM}Hc&w
} Ya4?{2h@+
7
Yv!N
/** mv
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* 本结果所在的页码,从1开始 ~I_owCVZ
* 8<PKKDgbfd
* @return Returns the pageNo. E[Bo4?s&^
*/ k&s; {|!
publicint getP(){ P{oAObP%
return p; ~a+NJ6e1
} <O857j
`6w#8}
/** (6xDu.u?A
* if(p<=0) p=1 [e"RTTRfZ
* DvT+`X?R
* @param p /8 CY0Ey
*/ *{/@uO
publicvoid setP(int p){ !sIwFv)
if(p <= 0) ]rX9MA6
p = 1; sB7" 0M
this.p = p; o)]FtL:mm
} y$oW!
i2F(GH?p[
/** D\rmaF+
* 每页记录数量 2cnj@E:5l
*/ |4SW[>WT:
publicint getNum(){ VuWib+fT
return num; }C~]=Z
} f$D@*33ft
e@
oWwhpE
/** .LE+/n
* if(num<1) num=1 79ZxqvB\
*/ c4] u&tvjJ
publicvoid setNum(int num){ ;L6Xs_L~
if(num < 1) L$JI43HZ
num = 1; .9 kyrlm
this.num = num; Ph)|j&]
} 6v47 QW|'
O-GxUHwWr
/** %Y',|+Arx
* 获得总页数 nm):SEkC
*/ !
zfFt;
publicint getPageNum(){ 5#uO'<2$
return(count - 1) / num + 1; mTjm92
} b(T@~P/
X4I]9t\
/** xXOw:A'
* 获得本页的开始编号,为 (p-1)*num+1 76MsrOv55
*/ 1_3?R}$Wl
publicint getStart(){ .uDM_ 34
return(p - 1) * num + 1; 1P5LH5
} ;X7i/DQ
j.&
;c'V$.
/** >h7$v~nra
* @return Returns the results. SfDQ;1?
*/ VK4/82@5
publicList<E> getResults(){ B)a@fmp"a
return results; NV~vuC
} nEVbfNo0
JD&U}dJ
public void setResults(List<E> results){ Tk+DPp^
this.results = results; -3k;u
} 6Q$BUL}2?
b;{h?xc6
public String toString(){ RZ6~c{
StringBuilder buff = new StringBuilder @XBH.A^7r
coAW9=o}
(); PW^ 8;[\QP
buff.append("{"); Z3`2-r_=
buff.append("count:").append(count); }xJR.]).KW
buff.append(",p:").append(p); hho%~^bn(
buff.append(",nump:").append(num); ZYKd
buff.append(",results:").append (6-y+LG
Lh!z>IWjOG
(results); ,aO@.<"
buff.append("}"); y< ud('D
return buff.toString(); msG3~@q
} j0?>w{e
J0qXtr%h\
} V/&o]b
/s8/q2:
MCd F!{