Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 p4OiCAW;
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 I5J9,j
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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 q={\|j$X
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 *0`oFTJ
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分页支持类: HjAQF?;V
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java代码: g.d%z
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package com.javaeye.common.util; Vuqm{bo^
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import java.util.List; OxraaN`
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publicclass PaginationSupport { *XK9-%3
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publicfinalstaticint PAGESIZE = 30; Vnv9<=R
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privateint pageSize = PAGESIZE; {rG`Upp
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privateList items; THM\-abz
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privateint totalCount; v@0lTl_
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privateint[] indexes = newint[0]; xED`8PCfu
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privateint startIndex = 0; t4H@ZvAH0
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public PaginationSupport(List items, int {zc<:^r^
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totalCount){ _ s]=g
setPageSize(PAGESIZE); 0NB6S&lI^k
setTotalCount(totalCount); lr[a~ca\
setItems(items); w$cic
setStartIndex(0); oO4
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} l*|^mx^Q
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public PaginationSupport(List items, int 2>3gC_^go
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totalCount, int startIndex){ :H$D-pbJ4
setPageSize(PAGESIZE); 6N&S3<c4JO
setTotalCount(totalCount); $GyO+xF
setItems(items); "bRg_]\q6
setStartIndex(startIndex); >Udb*76
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} onM ~*E
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public PaginationSupport(List items, int DG x9 \8^
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totalCount, int pageSize, int startIndex){ n7"e 79
setPageSize(pageSize); 6ZBg/_m
setTotalCount(totalCount); av( d0E}}b
setItems(items); D@yg)$;z
setStartIndex(startIndex); yWACIaj
} H V`{YuP
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publicList getItems(){ 4'W| '4'b
return items; &t+
} |#x;}_>7
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publicvoid setItems(List items){ %($qg-x
this.items = items; .F0V
} *Rv eR?kO
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publicint getPageSize(){ :>$)Snqo=n
return pageSize; z^Nnt
} b'^OW
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publicvoid setPageSize(int pageSize){ _dj<xPO
this.pageSize = pageSize; jGzs; bE
} *J!oV0#1
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publicint getTotalCount(){ ,epKt(vl
return totalCount; {}?s0U$5
} Q/6T?{\U7
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publicvoid setTotalCount(int totalCount){ _7YAF,@vT
if(totalCount > 0){ C|Bk'<MI
this.totalCount = totalCount; zYdSg<[^
int count = totalCount / ~F*pV*
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pageSize; GV1\8OG7
if(totalCount % pageSize > 0) QeA)@x.p
count++; K6kPNi
indexes = newint[count]; kx'ncxN~
for(int i = 0; i < count; i++){ &J_|P43
indexes = pageSize * YNbs*i&
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} Qw^nN(K!>
}else{ hA?j"y0?
this.totalCount = 0; sJX/YGHt
} h:(Jes2
} -gh',)R
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publicint[] getIndexes(){ $"T1W=;j9
return indexes; p2PD';"
} |H5){ 2V>K
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publicvoid setIndexes(int[] indexes){ iYA06~d
this.indexes = indexes; FpE83}@".w
} 1 ,o C:N
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publicint getStartIndex(){ %4 cUa| =?
return startIndex; 3O<<XXar
} {o7ibw=E)
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publicvoid setStartIndex(int startIndex){ =/J4(#Xb
if(totalCount <= 0) z.eqOPW
this.startIndex = 0; /`0*!sN*5
elseif(startIndex >= totalCount) AqvRzi(Y
this.startIndex = indexes ?V#%^ 57p
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[indexes.length - 1]; &Z5$
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elseif(startIndex < 0) 0G9@A8LU
this.startIndex = 0; B4R!V!Z*
else{ 'g#Ml`cm
this.startIndex = indexes fyx-VXu
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[startIndex / pageSize]; iwCnW7:
} o(>!T=f
} [9a0J):w{
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publicint getNextIndex(){ Q<zL;AJ
int nextIndex = getStartIndex() + $} l0Nh'Eu
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pageSize; b,7:=-D
if(nextIndex >= totalCount) N{iBVl
return getStartIndex(); 7*OO k"9
else 5JDqSz{
return nextIndex; =ALy.^J=
} JrseU6N
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publicint getPreviousIndex(){ E3.=|]W'
int previousIndex = getStartIndex() - }f^r@3Cb3
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pageSize; QY-P!JD
if(previousIndex < 0) >Fz_]z
return0; NaG1j+LN
else ZP*Hx
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return previousIndex; v*QobI
} z]Z>+|
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} l},*^Sn<5
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抽象业务类 zrU0YHmt
java代码: q+dY&4&u
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/** -n!.PsGO>
* Created on 2005-7-12 }0?642 =-
*/ +KDB^{
package com.javaeye.common.business; <|Bh;;
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import java.io.Serializable; }{:H0)H*
import java.util.List; f&H):.
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import org.hibernate.Criteria; %H~q3|z
import org.hibernate.HibernateException; =nA;,9%
import org.hibernate.Session; B!!xu
import org.hibernate.criterion.DetachedCriteria; ;Y
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import org.hibernate.criterion.Projections; WUGPi'x
import 0fXdE ;M3
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org.springframework.orm.hibernate3.HibernateCallback; ?nB).fc
import -&M9Yg|Se
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org.springframework.orm.hibernate3.support.HibernateDaoS :De}5BMy
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upport; 4Me*QYD
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import com.javaeye.common.util.PaginationSupport; Q)C#)|S
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public abstract class AbstractManager extends ov#/v\|0
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HibernateDaoSupport { XkCbdb
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privateboolean cacheQueries = false; tu6c!o,@
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privateString queryCacheRegion; ^g~Asz5]
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publicvoid setCacheQueries(boolean C:_!zY'z
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cacheQueries){ K4N~ApLB+
this.cacheQueries = cacheQueries; 45edyQ
} oA"t`,3
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publicvoid setQueryCacheRegion(String [}9R9G>"
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queryCacheRegion){ _|wgw^.LJ]
this.queryCacheRegion = 37a"<
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queryCacheRegion; N/8qd_:8
} CP |N2rb
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publicvoid save(finalObject entity){ $[VKM|Zjw
getHibernateTemplate().save(entity); I(s\ Q[
} c|:H/Y2n|
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publicvoid persist(finalObject entity){ SvAz9>N4
getHibernateTemplate().save(entity); :'f#0 ox
} zr\I1v]?1#
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publicvoid update(finalObject entity){ PX(.bP2^Lq
getHibernateTemplate().update(entity); j S')!Wcu
} =KmjCz:
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publicvoid delete(finalObject entity){ bb$1RLyRL
getHibernateTemplate().delete(entity); oS/<)>\Gv
} giyKEnP
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publicObject load(finalClass entity, 8QE0J$d5
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finalSerializable id){ {uL<$;#i
return getHibernateTemplate().load :w#Zs)N
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(entity, id); pTST\0?
} ]N:SB
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publicObject get(finalClass entity, 37v!:xF!
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finalSerializable id){ p=coOWOQ
return getHibernateTemplate().get Ii?<Lz
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(entity, id); ,`^B!U3m
} 8,a&i:C
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publicList findAll(finalClass entity){ 7F>5<Gv:-
return getHibernateTemplate().find("from }C}~)qaZv+
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" + entity.getName()); (NFq/w%
} pez[qs
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publicList findByNamedQuery(finalString %?<C
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namedQuery){ (VO)
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return getHibernateTemplate w_ kHy_)
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().findByNamedQuery(namedQuery); {e/12q
} RN5\,>+
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publicList findByNamedQuery(finalString query, PM=Q\0
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finalObject parameter){ (i.MxGDd
return getHibernateTemplate ]N*q3 y|)
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().findByNamedQuery(query, parameter); drBWo|/
} up=4B
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publicList findByNamedQuery(finalString query, 2ELw}9
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finalObject[] parameters){ 6m_Y%&
return getHibernateTemplate %DqF_4U 9
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().findByNamedQuery(query, parameters); y5kqnibh@
} czi$&(N0w$
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publicList find(finalString query){ L
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return getHibernateTemplate().find Cl7IP<.
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(query); m>x.4aO1
} \;&j;"c,W
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publicList find(finalString query, finalObject KqP!={>"
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parameter){ JX7_/P
return getHibernateTemplate().find |qH -^b.F
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(query, parameter); Lp5LRw
} >to NGGU=~
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public PaginationSupport findPageByCriteria UA!-YTh
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(final DetachedCriteria detachedCriteria){ .5 p"o-:D
return findPageByCriteria MH.,dB&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y#{ L}
} ?SK1*; i
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public PaginationSupport findPageByCriteria 4`o_r%
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(final DetachedCriteria detachedCriteria, finalint elG<\[
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startIndex){
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return findPageByCriteria F-R4S^eV
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(detachedCriteria, PaginationSupport.PAGESIZE, "^fcXV9Wp
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startIndex); .}&bE1
} w=
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public PaginationSupport findPageByCriteria Z*tB=
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(final DetachedCriteria detachedCriteria, finalint mDEO$:A
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pageSize, Obgn?TAVX
finalint startIndex){ 8~YhT]R=
return(PaginationSupport) ^q-]."W]t~
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getHibernateTemplate().execute(new HibernateCallback(){ H5'/i;
publicObject doInHibernate 'h53:?~
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(Session session)throws HibernateException { X=USQj\A
Criteria criteria = \HF|&@}hU
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detachedCriteria.getExecutableCriteria(session); }b)7gd=
int totalCount = vOy;=0$
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((Integer) criteria.setProjection(Projections.rowCount ?){V7<'?y
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()).uniqueResult()).intValue(); 5Mf bO3
criteria.setProjection 5,cq-`
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(null); .aV#W@iyK
List items = qF C0$:z&
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criteria.setFirstResult(startIndex).setMaxResults Hphvsre<
0"o%=i;
(pageSize).list(); w[}5qAI5*f
PaginationSupport ps = Jte:U*2
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new PaginationSupport(items, totalCount, pageSize, a'u:1C^\
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startIndex); XZde}zUWn
return ps; piIj
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} VRQ'sn@
}, true); [0<N[KZ)
} T}d%X MXq
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public List findAllByCriteria(final A:Pp;9wl
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DetachedCriteria detachedCriteria){ 8;K'77h
return(List) getHibernateTemplate A.vWGBR
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().execute(new HibernateCallback(){ 2XI%z4\)!
publicObject doInHibernate M:K5r7Q!yv
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(Session session)throws HibernateException { V<:scLm#OF
Criteria criteria = @'>h P
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detachedCriteria.getExecutableCriteria(session); x8
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return criteria.list(); bwN>E+
} 8WU_d`DF
}, true); V|[Y9<*
} D32~>J.F
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public int getCountByCriteria(final n=Qz7N(M
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DetachedCriteria detachedCriteria){ F|9 :$Jpw!
Integer count = (Integer) J:WO%P=Q
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getHibernateTemplate().execute(new HibernateCallback(){ =E$Hq4I
publicObject doInHibernate Ot,eAiaX
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(Session session)throws HibernateException { 0
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Criteria criteria = |uL"/cMW7
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detachedCriteria.getExecutableCriteria(session); L-SWs8
return {}x{OP
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criteria.setProjection(Projections.rowCount H|@R+
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()).uniqueResult(); vk;]9o j*
} %*J'!PC9n
}, true); 0P)"_x_
return count.intValue(); JR>v
} /DLgE7iU%
} R;D|To!
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用户在web层构造查询条件detachedCriteria,和可选的 Igb@aGA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 '1rHvz`B/"
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PaginationSupport的实例ps。 =6Z$nc
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ps.getItems()得到已分页好的结果集 lHl1Ny\?
ps.getIndexes()得到分页索引的数组 J+IkTqw
ps.getTotalCount()得到总结果数 @o otKY`
ps.getStartIndex()当前分页索引 Zq[aC0%+
ps.getNextIndex()下一页索引 M$L ;-T
ps.getPreviousIndex()上一页索引 F,F1Axf
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %v)m&VUi%
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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*I u6
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一下代码重构了。 *21foBfqh
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我把原本我的做法也提供出来供大家讨论吧: \9FWH}|
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首先,为了实现分页查询,我封装了一个Page类: ~r%>x
java代码: HzuB.B<
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/*Created on 2005-4-14*/ 9pY`_lxa>
package org.flyware.util.page; -h n~-Sy+
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/** Aw~N"i
* @author Joa A~Uqw8n$\
* i7 *cpNPO
*/ +0&SXhy%y
publicclass Page { 3d_PY,=1
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/** imply if the page has previous page */ g#Doed.30=
privateboolean hasPrePage; Z#Q)a;RA
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/** imply if the page has next page */ a
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privateboolean hasNextPage; iD/r8_}
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/** the number of every page */ heF<UMI
privateint everyPage; QAI!/bB
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/** the total page number */ gr&Rkuyfv
privateint totalPage; Q|3SYJf
@ -g'BvS
/** the number of current page */ k-~HUC.A.
privateint currentPage; |izf|*e
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/** the begin index of the records by the current |N^z=g P[
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query */ v<2B^(i}VB
privateint beginIndex; "?[7oI}c&
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/** The default constructor */ (l~3~n
public Page(){ ku`bwS
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} .*0`}H+_
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/** construct the page by everyPage +ISXyGu
* @param everyPage C/sDyv$
* */ 0'{`"QD\IW
public Page(int everyPage){ e.Y*=P}D
this.everyPage = everyPage; xUG:x4Gz+
} 4h[S`;D0Vf
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/** The whole constructor */ Nvef+L,v
public Page(boolean hasPrePage, boolean hasNextPage, 4_A9o9&_Rh
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int everyPage, int totalPage, /nX+*L}d/
int currentPage, int beginIndex){ |>Xw"]b;
this.hasPrePage = hasPrePage; TYs#v/)I
this.hasNextPage = hasNextPage; YflotlT}
this.everyPage = everyPage; 1V@\L|Y
this.totalPage = totalPage; cv'Fc
this.currentPage = currentPage; VB+sl2V<h
this.beginIndex = beginIndex; Xc^7
} /G>reG,G
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/** _`Abz2s
* @return ;7F|g
* Returns the beginIndex. H$
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*/ 4]\t6,Cz8
publicint getBeginIndex(){ 9hG+?
return beginIndex; YBX7WZCR
} i"rrM1/r
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/** CwV1~@{-
* @param beginIndex Z_^v#FJ'l
* The beginIndex to set. C~5-E{i
*/ E9Q?@' h
publicvoid setBeginIndex(int beginIndex){ MKuy?mri~
this.beginIndex = beginIndex; qwb`8o
} -CTsB)=\,
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/** <?TJ-
* @return &<u
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* Returns the currentPage. $j~oB:3n7
*/ _n3Jf<Y
publicint getCurrentPage(){ Oc]&1>M
return currentPage; l7]$Wc[
} wmNc)P4
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/** biFN]D
* @param currentPage GM/3*S$c
* The currentPage to set. N ".-]bB
*/ V zx%N.
publicvoid setCurrentPage(int currentPage){ S*H :/Ip
this.currentPage = currentPage; bW`@9 =E
} )-3!-1
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/** by {G{M`X
* @return ,{C(<1
* Returns the everyPage. GXEOgf#i
*/ ZOFBT(oV
publicint getEveryPage(){ Lp \%-s#5s
return everyPage; k?.HW?=zy
} lA4Bq
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/** n7vLw7
* @param everyPage
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* The everyPage to set. "9[K
*/ >4d2IO1\
publicvoid setEveryPage(int everyPage){ MwxfTH"wi
this.everyPage = everyPage; z]k=sk
} Ne]/ sQ0
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/** |Hbe]2"x>
* @return cJ&e^$:Er
* Returns the hasNextPage. }P$48o VY
*/ hfY
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publicboolean getHasNextPage(){ Rk
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return hasNextPage; s0Ii;7fA{
} &)vX7*j
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/** r\Wp\LfY&{
* @param hasNextPage j$*]'s&_hZ
* The hasNextPage to set. -Uz
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*/ ;G.m;5A
publicvoid setHasNextPage(boolean hasNextPage){ %PG::b
this.hasNextPage = hasNextPage; ay2
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} Rg&6J#h
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/** +w/Ax[K
* @return Ep}KIBBO
* Returns the hasPrePage. O.=~/!(
*/ {6<7M
publicboolean getHasPrePage(){ )o[ O%b
return hasPrePage; h<*l=`#
} xZ@H{):
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/** q[]!V0Ek10
* @param hasPrePage $JTy`g0>x
* The hasPrePage to set. n@BE*I<"
*/ +1p>:cih
publicvoid setHasPrePage(boolean hasPrePage){ 0D>~uNcT}
this.hasPrePage = hasPrePage; }H{{ @RU
} ?B %y)K
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/** gQ
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* @return Returns the totalPage. ]Bs ?
* 5;V#Z@S
*/ $*%Ml+H-
publicint getTotalPage(){ uLb-
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return totalPage; dUn8Xqj1
} o})4Jt1vj
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/** 8Es]WR5
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* @param totalPage b]s=Uv#)
* The totalPage to set. TE*$NxQ 2
*/ 0+8ThZ?n
publicvoid setTotalPage(int totalPage){ %_1~z[Dv
this.totalPage = totalPage; 76)(G/
} j:|60hDz^
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} -3VxjycY
| qHWM
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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 xn@?CP`-y
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个PageUtil,负责对Page对象进行构造: mo#4jtCE
java代码: pP?J(0Q~
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/*Created on 2005-4-14*/ Vw9^otJu
package org.flyware.util.page; N>Y`>5
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import org.apache.commons.logging.Log; #X"\:yN
import org.apache.commons.logging.LogFactory; [ZURs3q
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/** =Gd[Qn83.%
* @author Joa ]Nt97eD)
* ACl:~7;
*/ \\hZlCV,
publicclass PageUtil { GQ|kcY=
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privatestaticfinal Log logger = LogFactory.getLog z}C#+VhQ`
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(PageUtil.class); NfR, m]
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/** v.6"<nT2
* Use the origin page to create a new page =]xNpX)
* @param page .1I];Cy0D
* @param totalRecords r'&9'rir2
* @return }jiqUBn%
*/ ADv
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publicstatic Page createPage(Page page, int 6{azzk8
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totalRecords){ Cqg}dXn'
return createPage(page.getEveryPage(), ,l;
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(GPJ=r
page.getCurrentPage(), totalRecords); D{'Na5(
} T,7Y7MzF
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/** e,~c~Db*
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* the basic page utils not including exception o,\%c"mC
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handler a2=wJhk
* @param everyPage Y[s
* @param currentPage -&,NM
* @param totalRecords s7xRry
* @return page i'e^[oZ
*/ ;\<?LTp/r
publicstatic Page createPage(int everyPage, int Z(as@gjH
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currentPage, int totalRecords){ aGpRdF1;!
everyPage = getEveryPage(everyPage); niy@'
currentPage = getCurrentPage(currentPage); 4#2iL+
int beginIndex = getBeginIndex(everyPage, ~BS*x+M
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currentPage); AF3t#)q
int totalPage = getTotalPage(everyPage, M8cLh!!
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totalRecords); 'hya#rC&(
boolean hasNextPage = hasNextPage(currentPage, K7f-g]Ibdn
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totalPage); /mD KQ<
boolean hasPrePage = hasPrePage(currentPage); (sqS(xIY
)&dhE^
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returnnew Page(hasPrePage, hasNextPage, d}l^yln
everyPage, totalPage, cC}s5`
currentPage, @bqCs^U35
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v
beginIndex); -S,dG|
} YSa:"A
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privatestaticint getEveryPage(int everyPage){ [tD*\\IA
return everyPage == 0 ? 10 : everyPage; iBo-ANnK9
} 5\4>H6
o~4n8
privatestaticint getCurrentPage(int currentPage){ !zJ.rYZ=g`
return currentPage == 0 ? 1 : currentPage; c(Ha"tBJ
} rM=Hd/ki5
{eZj[*P
privatestaticint getBeginIndex(int everyPage, int #[KwR\b{:+
:X4\4B*~
currentPage){ :T{or-
return(currentPage - 1) * everyPage; 8dA/dMQ
} $s]@%6f
iMA) (ZS
privatestaticint getTotalPage(int everyPage, int zfo.S[R@
_-!6@^+
totalRecords){ CIaabn
int totalPage = 0; 6wu/6DO
]@8=e'V
if(totalRecords % everyPage == 0) "V^jAPDXb
totalPage = totalRecords / everyPage; %[Ds-my2
else I^ >zr.zA
totalPage = totalRecords / everyPage + 1 ; -+PPz?0
c''O+,L1+
return totalPage; CqX%V":2
} aZ0H)
\!^o<$s.G
privatestaticboolean hasPrePage(int currentPage){ Aj`4uFhiL
return currentPage == 1 ? false : true; C|lMXp\*
} unX^ MPpw
}jk^M|Z"Oz
privatestaticboolean hasNextPage(int currentPage, >{??/fBd-
>b$<lo
int totalPage){ Bhs`Y/Ls-
return currentPage == totalPage || totalPage == )?xt=9Lh
F"F(s!
0 ? false : true; /Z@.;M
} CTP%
cq=R
}>1E,3A:%G
} eS.]@E-T
Qdn:4yk
-qEr-[z
W
,U'hk%
NkJ^ecn%)
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。 y(S0
2v>l
"Jwz.,Y\
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 2kgm)-z
0jzA\ $oD
做法如下: ]e3nnS1*.
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[+!c-A:H
<qy+@t
的信息,和一个结果集List: .iS]aJJ
java代码: xD#/@E1'Y
.iYg RW=T
@t^2/H
?O
/*Created on 2005-6-13*/ $-0u`=!
package com.adt.bo; b7,qzh
' FK"-)s
import java.util.List; oaK~:'
B)|s.Ez
import org.flyware.util.page.Page; W6iIL:sp
GkC88l9z
/** S- H3UND"
* @author Joa Bx qCV%9o
*/ gi6_la+
publicclass Result { +vnaEy
dkLR
Q
private Page page; 1_QO>T'
:h3JDQe:.
private List content; x V e!
CP'-CQ\Q
/** 7.t$#fzi
* The default constructor wf4Q}l2,d
*/ F)IP~BE-k
public Result(){ =3:ltI.'*I
super(); A^7!+1*K+
} 6{~I7!m"
f1{ckHAY55
/** l*u@T|Fc$
* The constructor using fields 4jW{IGW
* *Tlv'E.M
* @param page FdqUv%(Em
* @param content k?#6j1pn
*/ 40E[cGz$*
public Result(Page page, List content){ neBkwXF!
this.page = page; 6p@ts`#
this.content = content; \2`U$3Q
} u&Fm}/x
6uyf
/** dB5DJ:$W$
* @return Returns the content. uprQy<I@
*/ ^PI49iB
publicList getContent(){ 9s)oC$\
return content; `jHGNi
} fjFy$NX&>
=jN]ckn
/** WToAT;d2h
* @return Returns the page. a?kQ2<@g
*/ ||4Dtg
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public Page getPage(){ j$^]WRt
return page; 5ZVTI,4K
} k.ZfjX"
-{h[W bf
/** C0%%@
2+
* @param content ?2TH("hV$
* The content to set. Z7^}G=*
*/ #O
WSy'Qnt
public void setContent(List content){ [;I8 ZVE
this.content = content; [oj"Tn(
} z#4g,)ZX
B(falmXJ
/** ||V:',#,W
* @param page -eMRxa>
* The page to set. qAS^5|(b[
*/ Nt8(
publicvoid setPage(Page page){ D6u>[Z[T
this.page = page; .vO.g/o
} Y"qY@`
} |@BN+o;`Om
UVK"%kW#(
[P/gM3*'
b nGA.b
sFQ|lU" n
2. 编写业务逻辑接口,并实现它(UserManager, 3_$eQ`AAA
Ub,unU
UserManagerImpl) "}! rM6 h
java代码: {76!
SOmn2
}
[/G;XHL;?
/*Created on 2005-7-15*/ R5"p7>
package com.adt.service; T8-$[
2
5WT\0]RUa
import net.sf.hibernate.HibernateException; ' T]oV~H
`?x$J
6p
import org.flyware.util.page.Page; dK: "
e`r;`a&
import com.adt.bo.Result; {P&^Erx
%5%Wo(W'
/** wY#mL1dF
* @author Joa Bv8C_-lV/
*/ VaxO L61xE
publicinterface UserManager { __j8jEV
nY)Pxahm 7
public Result listUser(Page page)throws Ao T 7sy7
L])w-
HibernateException; jhv1 D'>6
cqx1NWlY
} }=a4uCE
`Ny8u")=
2r,'4%G
$8k_M
keskD
java代码: NrcCUZ .:N
LltguNM$
pm\X*t}L
/*Created on 2005-7-15*/ }eM<A$J
package com.adt.service.impl; moR2iyO_
Ib!rf:
import java.util.List; RWFf-VA?
G:`Jrh
import net.sf.hibernate.HibernateException; Nl`ry2"<
C4]%pi
import org.flyware.util.page.Page; 2<Bv=B
import org.flyware.util.page.PageUtil; @88i/ Z_
Ky#B'Bh}`g
import com.adt.bo.Result; t[hocl/6
import com.adt.dao.UserDAO; on?/tHys
import com.adt.exception.ObjectNotFoundException; +E|ouFI
import com.adt.service.UserManager; 9^ p{/Io
|+-i'N9
/** RWCS
u$
* @author Joa &pjV4m|j<
*/ ~aAJn IO
publicclass UserManagerImpl implements UserManager { Y,btL'[W
f<Tz#w&6W
private UserDAO userDAO; a
+yI2s4Z
!m(L0YH
/** I^(#\vRW
* @param userDAO The userDAO to set. Aq%^>YAp
*/ @T1+b"TC
publicvoid setUserDAO(UserDAO userDAO){ Z&jb,eh2
this.userDAO = userDAO; '-33iG
} 8? Wxd65)
wg<|@z5
/* (non-Javadoc) 8G&+
* @see com.adt.service.UserManager#listUser +<9
eN
,$zlw\
(org.flyware.util.page.Page) I0+wczW,^
*/ 1xAFu+
public Result listUser(Page page)throws Uy5 !H1u
%@n8
?l4
HibernateException, ObjectNotFoundException { ir:~*|
int totalRecords = userDAO.getUserCount(); P 4*MV
if(totalRecords == 0) wI@I(r~g
throw new ObjectNotFoundException ^z}lGu
~49N
("userNotExist"); /I'u/{KB
page = PageUtil.createPage(page, totalRecords); `(/saq*
List users = userDAO.getUserByPage(page); e>9Z:vY
returnnew Result(page, users); Yc`j
} )kKmgtj
rw[ {@|)'z
} A]Tcj^#
,GkW. vEU
ds;cfj[
nVn|$ "r
ywynx<Wg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Kt,ynA
!L.
K)9I
询,接下来编写UserDAO的代码: dP7Vsa+
3. UserDAO 和 UserDAOImpl: ?4[Oh/]R
java代码: 4UD=Y?zK
U?mf^'RE
a,*p_:~i
/*Created on 2005-7-15*/ i4zV(
package com.adt.dao; Qy5Os?9"
D?yE$_3>c
import java.util.List; <o!&Kk 9
|\|)j>[i
import org.flyware.util.page.Page; ``|RO[+2
dMs||&|&
import net.sf.hibernate.HibernateException; {{*]bGko
AXP`,H
/** E<Dh_K
* @author Joa 6QLQ1k`
*/ BCUt`;q ]B
publicinterface UserDAO extends BaseDAO { BBR"HMa4
,ah*!Zm.kk
publicList getUserByName(String name)throws fA_%8CjI
=Y/fF
HibernateException; .^~l_LkA
}PQSCl^I
publicint getUserCount()throws HibernateException; MziZN^(
Np<s[dQ
publicList getUserByPage(Page page)throws ur<eew@8@i
6Z&u
HibernateException; ]osx.
]TBtLU3
} o9Txo
(tYU
qwF*(pTHq
S2&9#6
%8bzs?QI
+an^e'
java代码: ^{*f3m/
2Za,4'
w;c#drY7S
/*Created on 2005-7-15*/ 'ZC}9=_g
package com.adt.dao.impl; B3dA%\'
/MKNv'5&!%
import java.util.List; 0SMQDs5j
w3=)S\
import org.flyware.util.page.Page; nx-1*
O~h94 B`
import net.sf.hibernate.HibernateException; xY2}Wr
j,
import net.sf.hibernate.Query; Ni!;-,H+E
k%]DT.cE
import com.adt.dao.UserDAO; dv'E:R(a
xaWGa1V'z
/** h41$|lonU%
* @author Joa NFY|^*bll
*/ cZe'!CQS
public class UserDAOImpl extends BaseDAOHibernateImpl 7Ai o`&^
@)vy'qP d
implements UserDAO { t{Hh&HX
9^PRX
/* (non-Javadoc) 22GnbA7O
* @see com.adt.dao.UserDAO#getUserByName 4`8IFK
to&N22a$
(java.lang.String) \5Vp6^
*/ lk_s!<ni
publicList getUserByName(String name)throws X'FEOF
.]j#y9>&w%
HibernateException { 7|QGY7Tf
String querySentence = "FROM user in class 5#0A`QO
]-um\A4f
com.adt.po.User WHERE user.name=:name"; 3w/( /|0
Query query = getSession().createQuery crd|2bjp+
_Z+jQFKJ\8
(querySentence); \Pl,'
1%
query.setParameter("name", name); S<eZ d./p6
return query.list(); }XCR+uAz
} S5~`T7Ra
,!6M*|
/* (non-Javadoc) vuR5}/Ev
* @see com.adt.dao.UserDAO#getUserCount() MSZ!W(7,<
*/ jCTy:q]
publicint getUserCount()throws HibernateException { -`!_h[
int count = 0; B2~f;zy`
String querySentence = "SELECT count(*) FROM h; 'W :P
F0&~ ?2nG
user in class com.adt.po.User"; (PS$e~Hs
Query query = getSession().createQuery vpm ]9>1[
*o02!EYge
(querySentence); ORowx,(hX
count = ((Integer)query.iterate().next vWU%ST
Opv1B2
()).intValue(); +_qh)HX
return count; ytjK++(T5
} `'p`PyMt`
rI0)F
/* (non-Javadoc) rIeM+h7W n
* @see com.adt.dao.UserDAO#getUserByPage :E>&s9Yj?
}RcK_w@Jx)
(org.flyware.util.page.Page) Hp\Ddx >Jd
*/ V@vhj R4r\
publicList getUserByPage(Page page)throws m[Z6VHn
uR#'lb`3
HibernateException { IQ3n@
String querySentence = "FROM user in class @Ex;9F,Q
})@tA<+
com.adt.po.User"; L5Urg*GNL
Query query = getSession().createQuery Gn]d;5P=
QXdaMc+Ck
(querySentence); "r8EC
query.setFirstResult(page.getBeginIndex()) +XEjXH5K
.setMaxResults(page.getEveryPage()); 0iYP
return query.list(); u4:\UC'
} $
!v}xY
m!<X8d[bD
} 3az$:[Und}
4|nQ=bIau
"hWJ3pi{o{
xC-BqVJ%_T
^vpIZjN
至此,一个完整的分页程序完成。前台的只需要调用 n`% 2Mj c
su&t7rJ
userManager.listUser(page)即可得到一个Page对象和结果集对象 um;:fT+
%=V" CJ$|
的综合体,而传入的参数page对象则可以由前台传入,如果用 [UM Lx
@]f3|>I
webwork,甚至可以直接在配置文件中指定。 u7HvdLql
%y iD~&
下面给出一个webwork调用示例: |/VL35b
java代码: Uz 0W <u3v
Bi e?M
SD?BM-&~
/*Created on 2005-6-17*/ BI};"y
package com.adt.action.user; e
RA7i
dFQo
import java.util.List; `gt:gx>a
!"Qb}g
import org.apache.commons.logging.Log; &i5:)d]L
import org.apache.commons.logging.LogFactory; Yp*,Jp1
import org.flyware.util.page.Page; :
(gZgMT
#+9rjq:v#]
import com.adt.bo.Result; Y
%K~w
import com.adt.service.UserService; R'SBd}1
import com.opensymphony.xwork.Action; ,eDD:#)$}
R:"+ #Sq
/** Z!=L
* @author Joa ;)?( 2
wP
*/ AH^e]<2-
publicclass ListUser implementsAction{ 5G#$c'A{4
6mCq/$
privatestaticfinal Log logger = LogFactory.getLog :G -1YA
F;u7A]H^
(ListUser.class); F?z<xL@
s2%V4yy%
private UserService userService; 8h|M!/&2
Bz+.Qa+
private Page page; 2{-!E ^g
Vo,[EVL
privateList users; Edw2W8
U/Wrh($ #4
/* -/>9c-F
* (non-Javadoc) b6"}"bG
* T7{<arL$
* @see com.opensymphony.xwork.Action#execute() cGNvEM(4AV
*/ Q"%S~'
publicString execute()throwsException{ qe$33f*
Result result = userService.listUser(page); j$Nf%V 6Y
page = result.getPage(); O~ 27/
users = result.getContent(); MTb,Kmw<(
return SUCCESS; 1AF%-<`?s
} d",(aZ
d ;^
/** Sh&iQ_vq
* @return Returns the page. &~ *.CQa
*/ ZqQ*}l5
public Page getPage(){ wK ?@.l)u
return page; 2ev*CX6.
} =q+R
1a$IrQE
/** Q(Gyq:L=>
* @return Returns the users. EyY],W1 Y
*/ ^gOww6$ <
publicList getUsers(){ Z~p!C/B
return users; y<uAp
} X&a:g
q$gz_nVq,b
/** E ]B7
* @param page D`pQ7
* The page to set. 5qbq,#Pf
*/ :"QfF@Z{
publicvoid setPage(Page page){ NQX>Qh
2
this.page = page; o0ZBi|U\4
} Kb&V!#o)
JJ?I>S N!
/** ?^u^im
* @param users I{ ryD -!
* The users to set. 6Ps.E
*/ ?59'dGnz_
publicvoid setUsers(List users){ Zw{MgoJ0Z
this.users = users; M0L&~p_F
} %2"J:0j
|sIr?RL{C
/** +q{[\#t5
* @param userService kz B\'m,l
* The userService to set. khx.yRx
*/ c.%.\al8oW
publicvoid setUserService(UserService userService){ XF*.Jg]
this.userService = userService; M;jcUX_{
} m%QSapV
} 1J{fXh
5u$ D/*
Eb
&!L:"]=+
P4k;O?y
#.._c?%4/
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, Y$<D9fs3
pKT2^Q}-h
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 ]Gv!M?:
RWKH%C[Yd
么只需要: FhkkWWL
java代码: 3mO;JXd
c_.-b=zm
9QwKakci
<?xml version="1.0"?> mwC=o5O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork bsS:"/?>
SeEw.;Xw
1.0//EN" "http://www.opensymphony.com/xwork/xwork- n~.*1. P
v2)g 1sXd
1.0.dtd"> < zOi4v0
&nj&:?w
<xwork> "m$3)7 $
"6CMA0R
<package name="user" extends="webwork- KxzYfH
i47j lyH
interceptors"> =0qpVFvU
{"S6\%=
<!-- The default interceptor stack name D`yEwpV^
J2VTo: In
--> ["3\eFg
<default-interceptor-ref i7*EbaYzUO
4J0Rvod_
name="myDefaultWebStack"/> #Sh <