Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .=J- !{z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UIyLtoxu
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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 ;9mRumLG"
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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 f0sLe 3
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分页支持类: LxhS
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java代码: By8SRWs
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package com.javaeye.common.util; rP7
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import java.util.List; |{kbc0*
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publicclass PaginationSupport { cWx`y><
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publicfinalstaticint PAGESIZE = 30; ; >H1A
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privateint pageSize = PAGESIZE; .cJoNl'q
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privateList items; |Qcz5M90e
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privateint totalCount; KLW5Ad:/rI
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privateint[] indexes = newint[0]; W%>T{}4
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privateint startIndex = 0; )m;*d7l~p
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public PaginationSupport(List items, int 3#t#NW*e
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totalCount){ vO2WZ7E!
setPageSize(PAGESIZE); B_ict)}ld
setTotalCount(totalCount); rIFW1`N}i
setItems(items); ?{"r(
setStartIndex(0); 85G-`T
} C\5G43`
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public PaginationSupport(List items, int W/BPf{U
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totalCount, int startIndex){ _"@:+f,
setPageSize(PAGESIZE); a r8iuwfZ
setTotalCount(totalCount); [G$ #jUt/O
setItems(items); 4t(/F`
setStartIndex(startIndex); ]Pe>T&
} /Z?o%/bw:
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public PaginationSupport(List items, int >Vt2@Ee
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totalCount, int pageSize, int startIndex){ $T3_~7N
setPageSize(pageSize); 8Y`g$2SZ^8
setTotalCount(totalCount); axUj3J>
setItems(items); 7u&l]NC?y
setStartIndex(startIndex); K0(
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} e%)iDt\j
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publicList getItems(){ RKzty=j4
return items; -W^{)%4g
} {Cm!5Q Yy
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publicvoid setItems(List items){ R&(OWF;~,
this.items = items; qI7KWUR
} o+{,>t
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publicint getPageSize(){ m0;j1-t
return pageSize; n',X,P0
} 4Pc-A
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publicvoid setPageSize(int pageSize){ C5 ILVQ
this.pageSize = pageSize; ~{lb`M^]h
} ben-<3r
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publicint getTotalCount(){ 2fr%_GNu
return totalCount; ]'Eg2(wy
} \0 h>!u
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publicvoid setTotalCount(int totalCount){ G@ot^n3
if(totalCount > 0){ W8^A{l4
this.totalCount = totalCount; 9*s8%pL
int count = totalCount / <jJ'T?,
3>VL>;75[
pageSize; m
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if(totalCount % pageSize > 0) =JE<oVP8
count++; ]pe7I
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indexes = newint[count]; q-Z<.GTq
for(int i = 0; i < count; i++){ p3 5)K5V
indexes = pageSize * "W6cQsi
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i; @Ik5BT
} W[J2>`k9
}else{ ^}$t(t
this.totalCount = 0; _-RqkRI
} l=XZBe*[g'
} Y<W9LF
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publicint[] getIndexes(){ ru`7iqcz
return indexes; Fu{VO~w
} KB~[nZs7
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publicvoid setIndexes(int[] indexes){ )XonFI
this.indexes = indexes; NqF*hat
} ASi2;Q_{_
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publicint getStartIndex(){ cG0)F%?X?
return startIndex; aOg9Dqtg)f
} BKTTta1mY
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publicvoid setStartIndex(int startIndex){ BWX&5""
if(totalCount <= 0) (<.1o_Q-LU
this.startIndex = 0; VuZmX1x)N
elseif(startIndex >= totalCount) +o/;bm*U<K
this.startIndex = indexes %3VwCuE
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[indexes.length - 1]; m|"MJ P
elseif(startIndex < 0) .[Sv|;x"E
this.startIndex = 0; 6<t\KMd
else{ W^+bgg<.
this.startIndex = indexes 3G8uXB_`}
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[startIndex / pageSize]; e:V,>RbC0s
} c/2OR#$t
} f3l >26
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publicint getNextIndex(){ 6U+#ADo
int nextIndex = getStartIndex() + 0 q3<RX>M%
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pageSize; d)o<R;F
if(nextIndex >= totalCount) #t(?8!F
return getStartIndex(); "msg./iC
else a5)[?ol
return nextIndex; {U(h]'
} zPkg3H
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publicint getPreviousIndex(){ Mm[%v
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int previousIndex = getStartIndex() - 5^d%+*l;q
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pageSize; 2iG(v._x
if(previousIndex < 0) vp_ $6
return0; i~F Ct4
else ~IWi@m{
return previousIndex; d,)F #;^5
} R\Q%_~1
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} ytC{E_
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抽象业务类
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java代码: 8
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/** JX/d;N7a
* Created on 2005-7-12 +8Px` v1L
*/ jh?7+(Cw
package com.javaeye.common.business; & T|-K\*
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import java.io.Serializable; w0I
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import java.util.List; ?^!dLW
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import org.hibernate.Criteria; ,6bMfz
import org.hibernate.HibernateException; ;'
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import org.hibernate.Session; ).S<{zm7
import org.hibernate.criterion.DetachedCriteria; F@lpjW
import org.hibernate.criterion.Projections; e ^qnUjMy
import Rp|&1nS
@iceMD.
org.springframework.orm.hibernate3.HibernateCallback; k$ M4NF~$
import :&-}S>pC
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org.springframework.orm.hibernate3.support.HibernateDaoS 9C 05
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upport; Z4-dF;7
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import com.javaeye.common.util.PaginationSupport; n6Zx0ad?
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public abstract class AbstractManager extends %Eh%mMb^
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HibernateDaoSupport { Rx"Qwi, \U
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privateboolean cacheQueries = false; kw~H%-,]
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privateString queryCacheRegion; j1C.#-P[
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publicvoid setCacheQueries(boolean fEc_r:|\6
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cacheQueries){ t
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this.cacheQueries = cacheQueries; 5O W(] y|
} (NC>[
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publicvoid setQueryCacheRegion(String -\$cGIL
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queryCacheRegion){ kw:D~E(
this.queryCacheRegion = .6F3;bg R7
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queryCacheRegion; b[;3KmUB
} J\$l3i/I
3F} KrG
publicvoid save(finalObject entity){ M9g\/]Io;
getHibernateTemplate().save(entity); m =,c,*>
} $#FlnM<=
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publicvoid persist(finalObject entity){ HHTsHb{7
getHibernateTemplate().save(entity); }a1Sfl@`3
} >#U<#
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publicvoid update(finalObject entity){ {/xs9.8:JX
getHibernateTemplate().update(entity); O)JUY*&I5
} I*S`I|{J
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publicvoid delete(finalObject entity){ uEGPgYY (
getHibernateTemplate().delete(entity); X7d.Ie
} *Yu\YjLPG
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publicObject load(finalClass entity, U.7y8#qf3R
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finalSerializable id){ qZsddll
return getHibernateTemplate().load UZ\*]mxT
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(entity, id); Cm;qDvj+u
} V<V\0n!0
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publicObject get(finalClass entity, lJzy)ne
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finalSerializable id){ u1{ym_
return getHibernateTemplate().get 53t-'K0l
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(entity, id); /Ej]X`F
} GP[r^Z
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publicList findAll(finalClass entity){ n?LIphc\
return getHibernateTemplate().find("from s>VEuLY*
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" + entity.getName()); yb4tJu$
} n1>,#|#
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publicList findByNamedQuery(finalString YZH#5]o8
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namedQuery){ i,IM?+4
return getHibernateTemplate N~$Zeq=
q#(/*AoU
().findByNamedQuery(namedQuery); xe6_RO%
} _rMT{q3
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publicList findByNamedQuery(finalString query, hyOm9WU
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finalObject parameter){ 9vp%6[
return getHibernateTemplate D!RE-w92X
t*a*v;iz
().findByNamedQuery(query, parameter); Sc/`=h]T
} "@{4.v^}!
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publicList findByNamedQuery(finalString query, MKe^_uF
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finalObject[] parameters){ :6W^ S/pf
return getHibernateTemplate JEsLF{
ryB}b1`D
().findByNamedQuery(query, parameters); /!h;c$
} ^XbU~3(
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publicList find(finalString query){ M?m,EQh.
return getHibernateTemplate().find -Eu6U`"(
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(query); Wbr+KX8)
} &xRo^iV?
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publicList find(finalString query, finalObject "&/-N[is
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parameter){ 4=<tWa|@9
return getHibernateTemplate().find [8tL"G6s
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(query, parameter); (x/k.&
} Cj~'Lhmv'T
7}M2bH} \K
public PaginationSupport findPageByCriteria _S>JKz
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(final DetachedCriteria detachedCriteria){ '!/<P"5t
return findPageByCriteria ;4Y%PVz~D
^#-nE7
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0$,SF3K
} 0u\GO;
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public PaginationSupport findPageByCriteria dKdj`wB
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(final DetachedCriteria detachedCriteria, finalint 4$P0 :
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startIndex){ +E{|63~q
return findPageByCriteria h5(4*$%
\B,(k<
(detachedCriteria, PaginationSupport.PAGESIZE, )jt #=9ZQ
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startIndex); !QvZ<5(
} <yd{tD$A*
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public PaginationSupport findPageByCriteria 6_FE 4RR[
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(final DetachedCriteria detachedCriteria, finalint =>_\fNy
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pageSize, \SBc;
finalint startIndex){ (L/_^!ZX
return(PaginationSupport) neLAEHV
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getHibernateTemplate().execute(new HibernateCallback(){ [5SD_dN
publicObject doInHibernate 5yP\I+Fm
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(Session session)throws HibernateException { 0@%v1Oja
Criteria criteria = a ?)NC
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detachedCriteria.getExecutableCriteria(session); t:'Mh9h7u
int totalCount = G;l_|8<t#\
67Th;h*sh
((Integer) criteria.setProjection(Projections.rowCount w|K'M?N14
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()).uniqueResult()).intValue(); |R/%D%_g
criteria.setProjection -#N.X_F
}E50>g
(null); 9,:l8
List items = X:nN0p #
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criteria.setFirstResult(startIndex).setMaxResults Ju1D
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7`DBS^O]dG
(pageSize).list(); jK& h~)
PaginationSupport ps = CTq&-l:f
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new PaginationSupport(items, totalCount, pageSize, {tYZt4!{^
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startIndex); (ROY?5
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return ps; 42$VhdG
} 61k"p2?+
}, true); \Je0CD=e`
} i@"@9n~
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public List findAllByCriteria(final FQ<Ju.
(MxQ+D\
DetachedCriteria detachedCriteria){ !>..Q)z
return(List) getHibernateTemplate jCOIuw
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().execute(new HibernateCallback(){ hK L4cpK4
publicObject doInHibernate &^}1O:8e
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(Session session)throws HibernateException { cUKE
Criteria criteria = L*xhGoC=
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detachedCriteria.getExecutableCriteria(session); R O+GK`J
return criteria.list(); =.Pw`.
} fg_4zUGM+g
}, true); %Nlt H/I
} y" RF;KW>
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public int getCountByCriteria(final Y!-M_v /
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DetachedCriteria detachedCriteria){ <\rT%f}3^
Integer count = (Integer) yVU^M?`#
} gyj0
getHibernateTemplate().execute(new HibernateCallback(){ p& y<I6a,
publicObject doInHibernate ]7W&JKmA&
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(Session session)throws HibernateException { ^ Edfv5
Criteria criteria = 0L2 F[TN
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detachedCriteria.getExecutableCriteria(session); 4&HXkRs:
return %J8|zKT5t
@rHK(25+d
criteria.setProjection(Projections.rowCount /5#rADOS
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()).uniqueResult(); *#TYqCc+g
} (708H_
}, true); LPwT^zV&N
return count.intValue(); &*s0\
8
} .7
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} z`Hy'{1
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用户在web层构造查询条件detachedCriteria,和可选的 $O{duJU
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~Xlrvb}LP
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PaginationSupport的实例ps。 X]loJoM9
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ps.getItems()得到已分页好的结果集 {}o>{&X
ps.getIndexes()得到分页索引的数组 ?+c`]gO7N
ps.getTotalCount()得到总结果数 TrdZJ21#M
ps.getStartIndex()当前分页索引 hfcIvs/!
ps.getNextIndex()下一页索引 h C=:q
ps.getPreviousIndex()上一页索引 3@n>*7/E
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 PS
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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 !'=15&5@
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一下代码重构了。 K1?Gmue#I
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我把原本我的做法也提供出来供大家讨论吧: t!1$$e?`r
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首先,为了实现分页查询,我封装了一个Page类: 7{oe ->r
java代码: `N/RHb%
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/*Created on 2005-4-14*/ QO{y/{
package org.flyware.util.page; utlpY1#q/
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/** V2|3i}V"
* @author Joa 2h
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* :`vP}I ^
*/ $!A:5jech
publicclass Page { 1on'^8]0
jx_4B%kzq
/** imply if the page has previous page */ _ia! mT<
privateboolean hasPrePage; ]7AX%EG3
4\
/*jA
/** imply if the page has next page */ /"qcl7F
privateboolean hasNextPage; /DS?}I.*]
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/** the number of every page */ Lb=W;9;
privateint everyPage; d6 _C"r
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/** the total page number */ fn{S
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privateint totalPage; P}3}ek1Ax
#6S75{rnW"
/** the number of current page */ ZC^C
privateint currentPage; mjnUs-`W|
pF=g||gS
/** the begin index of the records by the current VU!w!GN]Y
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query */ \Mx
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privateint beginIndex; j;P+_Hfe/E
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/** The default constructor */ {M~lbU
public Page(){ ]Nk!4"
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} uf) Oy7FQ
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/** construct the page by everyPage "4}wnu6/
* @param everyPage uVU`tDzd:
* */ j=sBq.S
public Page(int everyPage){ 7$T8&Mh
this.everyPage = everyPage; Zy]s`aa
} ,=w!vO5s
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/** The whole constructor */ rAL1TU(vm
public Page(boolean hasPrePage, boolean hasNextPage, :82?'aR
yg`E22
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int everyPage, int totalPage, FF8WTuzB+
int currentPage, int beginIndex){ ?{?Vy9'B
this.hasPrePage = hasPrePage; _dJp
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this.hasNextPage = hasNextPage; B*32D8t`u
this.everyPage = everyPage; j1W
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this.totalPage = totalPage; ;B*L1'FF%t
this.currentPage = currentPage; m9%yR"g9
this.beginIndex = beginIndex; YmZC?x_{M2
} $ #TID=
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/** gQu\[e%mVo
* @return _F! :(@}
* Returns the beginIndex. i?lX,9%
*/ FpwlV}:
publicint getBeginIndex(){ Hf;RIl2F
return beginIndex; 2Y9y5[K,F)
} *QMF
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/** Bi'I18<
* @param beginIndex .%|OGl ?
* The beginIndex to set. <{3q{VW*
*/ B.{8/.4
publicvoid setBeginIndex(int beginIndex){ UDhwnGTq(l
this.beginIndex = beginIndex; ?IL!
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} -HO6K)ur
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/** ---Ks0\V
* @return I|Vk.,
* Returns the currentPage. |:!EHFr
*/ u40b?
n.
publicint getCurrentPage(){ t't^E,E
.@
return currentPage; ~nLkn#Z
} B^E2UNRA
l:>qR/|m
/** <P?3GT/
* @param currentPage WM~J,`]J
* The currentPage to set. YzforM^F
*/ l4R<`b\Jt
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; ^sr:N5~z`
} m-~V+JU;x
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/** G}Qk!r
* @return >"PqQO
* Returns the everyPage. .3S\Rrv
*/ Kt/+PS
publicint getEveryPage(){ Z7mGC`>
return everyPage; RE(=! 8lGR
} s$2l"|h>B
ai<MsQQ:=
/** 4{Yy05PFS
* @param everyPage \E ? iw.}
* The everyPage to set. }uV?
*/ 0C"PC:h5
publicvoid setEveryPage(int everyPage){ 5kRwSOG%'
this.everyPage = everyPage; i+qLc6|S=2
} E'Fv *UA
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/** 6x (L&>F
* @return ~t.WwxY+
* Returns the hasNextPage. _taHf %\4
*/ %Mb(
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publicboolean getHasNextPage(){ {YO%JTQ
return hasNextPage; }
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} u]>>B>KOJ7
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/** + 8K1]'t$
* @param hasNextPage aJa^~*N/Aa
* The hasNextPage to set. H-\{w
*/ vwqN;|F
publicvoid setHasNextPage(boolean hasNextPage){ 0:B^
this.hasNextPage = hasNextPage; _WjETyh
[H
} Kn!0S<ssR
jhEg#Q$
/** s2kZZP8-
* @return U<,Kw6K
* Returns the hasPrePage. zcD_}t_K
*/ rJc)<OZjT
publicboolean getHasPrePage(){ ;MRC~F=
return hasPrePage; e
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} dD.d?rnZq7
eE.5zXU3R
/** DP6{HR$L
* @param hasPrePage \gI:`>-
x
* The hasPrePage to set. :2UC{_
*/ z)Q^j>%
publicvoid setHasPrePage(boolean hasPrePage){ y!6:
this.hasPrePage = hasPrePage; `j!2uRFe>
} HT,kx
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/** +S5_J&~
* @return Returns the totalPage. EAd:`X,Y
* =u3@ Dhw
*/ `TlUJ]d)
publicint getTotalPage(){ 0-~6}
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return totalPage; ~~:8Yv[(
} 4@mXtA
QH' [(
/** `jQ}^wEgu
* @param totalPage FvNSu"O~K1
* The totalPage to set. o(>-:l i0
*/ ?5YmE(v7
publicvoid setTotalPage(int totalPage){ g\{! 21M
this.totalPage = totalPage; q}F%o0
} 6j"I5,-~!
-J7,Nw
} Is6']bYh
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 '/Cz{<,
1gy}E=noP
个PageUtil,负责对Page对象进行构造: 6BN(^y#-X
java代码: &aAo:pj
#M^Yh?~%w
c)!s[o L
/*Created on 2005-4-14*/ pL/.JzB
package org.flyware.util.page; `L*;58MA
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import org.apache.commons.logging.Log; p>tdJjnt
import org.apache.commons.logging.LogFactory; |wb(rua
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/** W>wi;Gf#
* @author Joa DD$Pr&~=
* [5eT|uy
*/ n9/0W%X>
publicclass PageUtil { _%Ld
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privatestaticfinal Log logger = LogFactory.getLog UR2)e{RXg
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(PageUtil.class); \J:T]
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/** 49fq6ZhO
* Use the origin page to create a new page khIa9Nm
* @param page sK/"
* @param totalRecords ~tuFjj^
* @return 6SO7iFS
*/ rPpAg
publicstatic Page createPage(Page page, int GFa/9Bi
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totalRecords){ 5t?2B]
return createPage(page.getEveryPage(), 9:w,@Phe
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page.getCurrentPage(), totalRecords); l{o{=]x1
} Z2jb>%
pP,bW~rk
/** ~WXxVm*@
* the basic page utils not including exception &*GX:0=/>
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handler Fh$&puF2
* @param everyPage 2vQ^519
* @param currentPage (+ anTA=
* @param totalRecords O9)}:++T
* @return page N4jLbnA
*/ >!.9g
publicstatic Page createPage(int everyPage, int xG/qDc
wu&7#![,
currentPage, int totalRecords){ 4yv31QG$
everyPage = getEveryPage(everyPage); `3oP^#
currentPage = getCurrentPage(currentPage); a\_,_psK
int beginIndex = getBeginIndex(everyPage, A'(F%0NF6
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currentPage); tgA
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int totalPage = getTotalPage(everyPage, fEv36xb2S
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totalRecords); H H3
boolean hasNextPage = hasNextPage(currentPage, 7"i*J6y*
4:g:$s|SE[
totalPage); Asu"#sd
boolean hasPrePage = hasPrePage(currentPage); 'FFc"lqj
IuW10}"9
returnnew Page(hasPrePage, hasNextPage, AI; =k
everyPage, totalPage, xR`2+t&t
currentPage, !#qB%E]a
$7d"9s\$"
beginIndex); 6E]rxps}"
} 1Di&vpn0u
nB0ol-<
privatestaticint getEveryPage(int everyPage){ Ntiz-qW
return everyPage == 0 ? 10 : everyPage; ZE`{J=,
} y8z%s/gRh
zUqDX{I8
privatestaticint getCurrentPage(int currentPage){ -1JHhRr]
return currentPage == 0 ? 1 : currentPage; cyNLeg+O*
} G].KJ5,y
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privatestaticint getBeginIndex(int everyPage, int #KW:OFT
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currentPage){ 9 To6Rc;
return(currentPage - 1) * everyPage; Z-(HDn
} 6~>k]G
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privatestaticint getTotalPage(int everyPage, int _@2G]JD
9l]IE,u
totalRecords){ nT"z(\i.!J
int totalPage = 0; Dzr5qP?#
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if(totalRecords % everyPage == 0) ]XU#i#;c
totalPage = totalRecords / everyPage; [_n|n"M
else KK</5Aw9p
totalPage = totalRecords / everyPage + 1 ; 2l?J9c}Wo
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return totalPage; \.]
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} Lt_]3go
}q9f,mz
privatestaticboolean hasPrePage(int currentPage){ 3yN1cd"#?
return currentPage == 1 ? false : true; F1>,^qyG6
} tO7{g
*OiHrI9y
privatestaticboolean hasNextPage(int currentPage, 2uVm?nm
soF ^G21N
int totalPage){ :%{7Q$Xv<
return currentPage == totalPage || totalPage == 0P(}e[~Z
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0 ? false : true; dyd_dK/
} u2QJDLMJv
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} *?{)i~
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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。 R07Kure
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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 =6b^j]1
/dpEL9K
做法如下: ql5NSQ>{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 `7qZ6Z3z@
vn@9Sqk
的信息,和一个结果集List: fu3/ n@L
java代码: >3V{I'^^-
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<Q'J=;vV
/*Created on 2005-6-13*/ xJ>U_Gd
package com.adt.bo; +]-~UsM
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import java.util.List; H8+7rM
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import org.flyware.util.page.Page; 8KRm>-H)
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/** X>^St&B}fC
* @author Joa VSa\X~
*/ E7-il;`cKn
publicclass Result { W' w;cy:H
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private Page page; a#t:+iw
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private List content; \<WRk4D
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/** rf_(pp)
* The default constructor /1ZRjf^
*/ S%zn {1F
public Result(){ <eP`Lu"
super(); 7M*&^P\}es
} U:xY~>
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/** WPT0=Hqp7
* The constructor using fields ZYr6Wn
* NO5\|.,Z
* @param page tB4dkWt.}
* @param content M:6Yy@#T.
*/ X}*\/(fzl
public Result(Page page, List content){ xi|T7,\X
this.page = page; *@`Sx'5!
this.content = content; 34S0W]V
} ayR=GqZ1
&`+tWL6L
/** Kx,#Wg{H
* @return Returns the content. #[$^M:X.
*/ r'!L}^n
publicList getContent(){ F
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return content; KQGdV{VFs
} aQzDOeTi
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/** \\w<.\Yh
* @return Returns the page. ;7,>2VTm
*/ -\=s+n_ZP?
public Page getPage(){ (55k70>i3
return page; H,8HGL[l
} EjxzX1:
FfEP@$
/** t!^ j0 q
* @param content hO8~Rg
* The content to set. Cn6<I {`\
*/ )wT@`p"4
public void setContent(List content){ ,j3Yvn W
this.content = content; :Y4m3|
} 1nGpW$Gx
Owd{;
/** LT+QW
* @param page ":igYh
* The page to set. jimWLF5Q5"
*/ LR`]C]
publicvoid setPage(Page page){ C?OqS+
this.page = page; Xg<R+o
} .|?UqZ(,
} Cpg>5N~;L
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2. 编写业务逻辑接口,并实现它(UserManager, a8w/#!^34
Pl/}`H:R&
UserManagerImpl) g.,_E4L
java代码: ==!k99`f,
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1#Q~aY
/*Created on 2005-7-15*/ 7gnrLc$]O
package com.adt.service; Kry^47"
|#i|BVnoE
import net.sf.hibernate.HibernateException; k]"DsN$
W ])Lc3X
import org.flyware.util.page.Page; u%24%
Q
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import com.adt.bo.Result; bnzIDsw!Q
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/** ]8o[&50y
* @author Joa e8,!x9%J
*/ hVGK%HCz&
publicinterface UserManager { Sv>bU4LHf
uXuA4o$t-
public Result listUser(Page page)throws s2kom)
9%iv?/o*L
HibernateException; 1e)5D& njS
7*>(C*q=
} wf""=;
J#) %{k_
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java代码: w:3CWF4q]
\N a
(yO8G-Z0
/*Created on 2005-7-15*/ L7"B`oa(p
package com.adt.service.impl; njGZ#{"eC
aS/ MlMf
import java.util.List; ZOzwO6(_
g!I0UAm
import net.sf.hibernate.HibernateException; p/ au.mc
$,8}3R5}
import org.flyware.util.page.Page; pT<}n 9yB5
import org.flyware.util.page.PageUtil; <!a%GI
q c DJ
import com.adt.bo.Result; #McX
import com.adt.dao.UserDAO; <d~IdK'\x
import com.adt.exception.ObjectNotFoundException; Sej(jJX1
import com.adt.service.UserManager; uGY(`
Z@gEJ^"yA"
/** U}c05GiQw
* @author Joa u!TMt8+c
*/ hOR1RB
publicclass UserManagerImpl implements UserManager { Gq =i-I
gxCl=\
private UserDAO userDAO; bOdQ+Y6
r68d\N`.
/** |*y'H*
* @param userDAO The userDAO to set. 4O'%$6KR(
*/ W/G75o~6
publicvoid setUserDAO(UserDAO userDAO){ k~=W1R%
this.userDAO = userDAO; I`uOsZBO/
} H|s,;1#
qK,PuD7i"
/* (non-Javadoc) AkA2/7<[
* @see com.adt.service.UserManager#listUser qMmhVUx
SGUZ'}
(org.flyware.util.page.Page) +qee8QH
*/ wj-z;YCV
public Result listUser(Page page)throws m98w0D@Ee
iu'At7
HibernateException, ObjectNotFoundException { zdgSqv
int totalRecords = userDAO.getUserCount(); _\u?]YTv
if(totalRecords == 0) uU!}/mbo
throw new ObjectNotFoundException q4]Qvf>
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("userNotExist"); qU+qY2S:
page = PageUtil.createPage(page, totalRecords); AR6hfdDDT
List users = userDAO.getUserByPage(page); Qt"i
returnnew Result(page, users); {"hyr/SK d
} 18AlQ+')?w
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} 0<u(!iL
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Vy@0Got5=
7qEc9S@
询,接下来编写UserDAO的代码: !xz{X ?
3. UserDAO 和 UserDAOImpl: *s6(1S
java代码: 4nU+Wj?T
hDD]Kc;G^1
W,|JocDq
/*Created on 2005-7-15*/ !"s~dL,7
package com.adt.dao; FSA"U9 w<
/YD2F
import java.util.List; {7d\du&G
\) vI-
import org.flyware.util.page.Page; p[:E$#W~;
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import net.sf.hibernate.HibernateException; JXk<t5@D
xv~EwT)
/** 1Gh3o}z
* @author Joa G\/7V L
*/ iU "{8K,
publicinterface UserDAO extends BaseDAO { u8Oo@xf0Fr
U_
*K%h\m
publicList getUserByName(String name)throws @{o3NR_
<S(`e/#[
HibernateException; S|/Za".Gr
Ct0YwIR*
publicint getUserCount()throws HibernateException; ">!<