Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #G^?4Za
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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 &}%3yrU
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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 >t
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分页支持类: sL
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java代码: Bi)1*
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package com.javaeye.common.util; 6<R!`N 6
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import java.util.List; S!k cC-7
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publicclass PaginationSupport { SV}I+O_w
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publicfinalstaticint PAGESIZE = 30; /N7j5v(
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privateint pageSize = PAGESIZE; =zt@*o{F
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privateList items; -Yy,L%E]F:
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privateint totalCount; NI\jGR.
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privateint[] indexes = newint[0]; [GX5jD#
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privateint startIndex = 0; `\P#TBM
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public PaginationSupport(List items, int 1p<m>s=D=e
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totalCount){ (u+3{Eb
setPageSize(PAGESIZE); 3VbMW, _&"
setTotalCount(totalCount); =U!M,zw4
setItems(items); {Tl5,CAz
setStartIndex(0); m@R!o
} |vw0:\/H
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public PaginationSupport(List items, int +;tXk
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totalCount, int startIndex){ yf*^Y74
setPageSize(PAGESIZE); D$+9`
setTotalCount(totalCount); !v;N@C3C
setItems(items); i<l_z&
setStartIndex(startIndex); +*]"Yo~]}
} 'kf]l=i[n
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public PaginationSupport(List items, int fgK1+sW
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totalCount, int pageSize, int startIndex){ EaaQC]/OX5
setPageSize(pageSize); c"Ddw'?e
setTotalCount(totalCount); oOlqlv
setItems(items); V}o`9R@tx}
setStartIndex(startIndex); tAO,s ZW
} HjAhz
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publicList getItems(){ +sq'\Tbp
return items; >7i&(6L
} GX?R# cf
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publicvoid setItems(List items){ }W^%5o87{
this.items = items; lKWe=xY\B
} jD1/`g%
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publicint getPageSize(){ =jXBF.
return pageSize; g<pr(7jO
} KT$Za
M#%l}
publicvoid setPageSize(int pageSize){ SO @d\H
this.pageSize = pageSize; j5\z7
} @+Ch2Lod
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publicint getTotalCount(){ Q*4{2oQ
return totalCount; uH*moVw@5
} K#Ia19au5
kNq>{dNRx
publicvoid setTotalCount(int totalCount){ FM$$0}X
if(totalCount > 0){ c12mT(+-
this.totalCount = totalCount; j.=&qYc0"
int count = totalCount / e1cqzhI=nA
s0r::yO
pageSize; nv$>iJ^~H
if(totalCount % pageSize > 0) %Q,6 sH#
count++; 3dO~Na`S
indexes = newint[count]; mok94XuK)
for(int i = 0; i < count; i++){ xER-TT#S
indexes = pageSize * ob3)bI oM
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i; ?D>%+rK8c
} l4Au{%j\
}else{ UHyGW$B
this.totalCount = 0; K
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} }H#C<:A
} <JUumrEo
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publicint[] getIndexes(){ fQm3D%
return indexes; zv.#9^/y
} 6JgbJbUi
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publicvoid setIndexes(int[] indexes){ b=@H5XTZyK
this.indexes = indexes; -HwqR Ys
} H0(.p'eN
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publicint getStartIndex(){ J]W?
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return startIndex; a``/x_EZMn
} g3|k-
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publicvoid setStartIndex(int startIndex){ ?_-5W9
if(totalCount <= 0) s4uZ >
this.startIndex = 0; nt:ZO,C:R
elseif(startIndex >= totalCount) 4V<.:.k
this.startIndex = indexes xWK0p'E0
8q]_> X
[indexes.length - 1]; fQU5' wGp
elseif(startIndex < 0) B/Js>R
this.startIndex = 0; q#6|/R*
else{ D dh
this.startIndex = indexes XqLR2d
/Qu<>#[?
[startIndex / pageSize]; 3mQ3mV:
} }wB!Bx2
} <<DPer2
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publicint getNextIndex(){ `*o ko[\3
int nextIndex = getStartIndex() + Py`7)S
v}5||s!=
pageSize; o)wOXF
if(nextIndex >= totalCount) ug_c}Nv=Y
return getStartIndex(); V~_6t{L
else !a4`SjOgu
return nextIndex; Xz?7x0)Z
} %!7A" >ai
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publicint getPreviousIndex(){ d};[^q6X
int previousIndex = getStartIndex() - C1#f/o ->
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pageSize; $0cE iq?Hf
if(previousIndex < 0) gj7'43
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return0; _1jbNQa
else #nQboTB@
return previousIndex; G?^w
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} 4Wu(Tps
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} I^)_rOgM
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抽象业务类 l*Q OM
java代码: BI<(]`FP;s
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/** sDvy(5
* Created on 2005-7-12 8PqlbLo1
*/ r3Kx
package com.javaeye.common.business; tI
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import java.io.Serializable; 6o^O%:0g
import java.util.List; aI;fNy/K
u= Ga}
import org.hibernate.Criteria; a# Uk:O!
import org.hibernate.HibernateException;
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import org.hibernate.Session; mC$ te
import org.hibernate.criterion.DetachedCriteria; Q>xp 90&.n
import org.hibernate.criterion.Projections; rcf#8
import {qm5H7sL
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org.springframework.orm.hibernate3.HibernateCallback; S] 4RGWn
import -j^G4J
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org.springframework.orm.hibernate3.support.HibernateDaoS wuhL r(
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upport; )7m.n%B!5V
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import com.javaeye.common.util.PaginationSupport; QbYNL9%
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public abstract class AbstractManager extends ZC &~InN
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HibernateDaoSupport { ioslarw1J
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privateboolean cacheQueries = false; j[=P3Z0q
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privateString queryCacheRegion; 2bf#L?5g/
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publicvoid setCacheQueries(boolean >BjZ{7?Ok
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cacheQueries){ `)H|
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this.cacheQueries = cacheQueries; j2|UuWU
} WhL"-f
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publicvoid setQueryCacheRegion(String %G jjl*`E
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queryCacheRegion){ ([ hd
this.queryCacheRegion = VjSA&R
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queryCacheRegion; P1ynCe
} +s5Yg,4*
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publicvoid save(finalObject entity){ Z?'?+48xv4
getHibernateTemplate().save(entity); c+u) C%g
} B)ibxM(n*
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publicvoid persist(finalObject entity){ 3
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getHibernateTemplate().save(entity); M5B?`mTl
} =!2(7Nr
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publicvoid update(finalObject entity){ i'0ol^~y6
getHibernateTemplate().update(entity); Va\?"dH>M
} T( bFn?
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publicvoid delete(finalObject entity){ <V*M%YWs
getHibernateTemplate().delete(entity); M+\LH
} N Z~"2~Hh
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publicObject load(finalClass entity, >c@1UEwkm
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finalSerializable id){ s KOy6v
return getHibernateTemplate().load @RS|}M^4
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(entity, id); >l!DWi6
} 4 Yl:1rz
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publicObject get(finalClass entity, V:
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finalSerializable id){ \YsYOFc|
return getHibernateTemplate().get qn@:A2ed
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(entity, id); Hh.l,Z7i7D
} (:T\<
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publicList findAll(finalClass entity){ fmq9u(!R
return getHibernateTemplate().find("from cXvq=Rb
[?Q$b5j/M
" + entity.getName()); <f`G@
} k
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publicList findByNamedQuery(finalString /
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namedQuery){ TwXqk>J
return getHibernateTemplate (lVHKg&U[
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().findByNamedQuery(namedQuery); -:o4|&g<*
} {z/Y~rf
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publicList findByNamedQuery(finalString query, \`M8Mu9~w
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finalObject parameter){ qA6;Q$
return getHibernateTemplate pT` oC&
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().findByNamedQuery(query, parameter); -(]s!,
} B#K{Y$!v
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publicList findByNamedQuery(finalString query, "?UBW5nM#
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finalObject[] parameters){ &%Lps_+fJ
return getHibernateTemplate &{c.JDO
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().findByNamedQuery(query, parameters); Yq?FiE0
} [_h/DhC:+
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publicList find(finalString query){ 2=PX1kI
return getHibernateTemplate().find af<R.
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(query); $kA'9Y
} E9IU,P6a
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publicList find(finalString query, finalObject j:;[Y `2
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parameter){ )E.!jL:g
return getHibernateTemplate().find <!s+X_^
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(query, parameter); eI7FbOze
} %9!,PeRe
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public PaginationSupport findPageByCriteria ""JTU6]MS
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(final DetachedCriteria detachedCriteria){ ST#MCh-00
return findPageByCriteria [%alnY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); oK5"RW
} +;P8QZK6
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public PaginationSupport findPageByCriteria J.r^"K\
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(final DetachedCriteria detachedCriteria, finalint s^{hdCCl67
s^@?+<4:
startIndex){ _qq> 43
return findPageByCriteria .S l{m[nV8
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(detachedCriteria, PaginationSupport.PAGESIZE, 8T7E.guYr
4'ym vR
startIndex); 3~I|KF7x
} -_bnGY%,
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public PaginationSupport findPageByCriteria b1(7<o
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(final DetachedCriteria detachedCriteria, finalint vU:FDkx*nn
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pageSize, WUwH W
finalint startIndex){ (h}5*u%h
return(PaginationSupport) g[]UM;D*
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getHibernateTemplate().execute(new HibernateCallback(){ Tq\S-K}4!
publicObject doInHibernate 6`>WO_<z
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(Session session)throws HibernateException { ~6HpI0i
Criteria criteria = \{Qd
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detachedCriteria.getExecutableCriteria(session); 0Jz5i4B
int totalCount = 0pO{ {F
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((Integer) criteria.setProjection(Projections.rowCount #H'j;=]:
#DBg8
()).uniqueResult()).intValue(); *>lh2sslL
criteria.setProjection 8T7ex(w
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(null); TzaR{0
1
List items = 3pxZk%
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criteria.setFirstResult(startIndex).setMaxResults qO;.{f
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(pageSize).list(); f<14-R=
PaginationSupport ps = m*Zq3j
(=2-*((&(A
new PaginationSupport(items, totalCount, pageSize, e-!6m#0
?IKSSe#,
startIndex); rq>}]
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return ps; `!`g&:Y
} !2.(iuE
}, true); wzXIEWJ
} v r=va5
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public List findAllByCriteria(final prHM}n{0
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DetachedCriteria detachedCriteria){ 4YuJ -
return(List) getHibernateTemplate ?z
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().execute(new HibernateCallback(){ K nl`[Nl
publicObject doInHibernate 4YV0v,z
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(Session session)throws HibernateException { i\zVP.c])*
Criteria criteria = 8a,uM :
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detachedCriteria.getExecutableCriteria(session); S/itK3
return criteria.list(); ]C;X/8'Jf5
} x|b52<dLL&
}, true); %E R"Udh
} uPT2ga ]
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public int getCountByCriteria(final @A5'vf|2;.
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DetachedCriteria detachedCriteria){ %.h&W;
Integer count = (Integer) ]c9\[Kdq}H
o2 ;
getHibernateTemplate().execute(new HibernateCallback(){ r|_@S[hZg
publicObject doInHibernate &E]<dmR
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(Session session)throws HibernateException { V&h{a8xa$
Criteria criteria = RoFOjCc>D.
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detachedCriteria.getExecutableCriteria(session); aw923wEi
return [n2+`A
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criteria.setProjection(Projections.rowCount ,M.phRJ-`
4,P(w+
()).uniqueResult(); 1KUM!DUD
} I}jem
}, true); 45,): U5
return count.intValue(); g5C$#<28
} EY`]""~8v
} .6=;{h4cpB
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用户在web层构造查询条件detachedCriteria,和可选的 j8G$ , ~v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6U0BP
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PaginationSupport的实例ps。 Xw#"?B(M]
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ps.getItems()得到已分页好的结果集 !,^y!+,Qy
ps.getIndexes()得到分页索引的数组 VaW^;d#
ps.getTotalCount()得到总结果数 \ iA'^69
ps.getStartIndex()当前分页索引 JvsL]yRT
ps.getNextIndex()下一页索引 `6P2+wf1j~
ps.getPreviousIndex()上一页索引 VRZqY7j}g
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 UcKVLzKs
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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 ^`[<%.
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一下代码重构了。 o`Af6C;Q
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我把原本我的做法也提供出来供大家讨论吧: H#uN&^+H
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首先,为了实现分页查询,我封装了一个Page类: $NCR
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java代码: |~ytAyw
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/*Created on 2005-4-14*/ \*&?o51!e
package org.flyware.util.page; }d>Xh8:%)
@u`W(Ow
/** E+ |K3EJ
* @author Joa %gQUog
* NJSbS<O
*/ (?g+.]Dt,
publicclass Page { B9Mp3[
<CB%e!~.9
/** imply if the page has previous page */ c&P/v#U_
privateboolean hasPrePage; @lX%Fix9
lXF7)H&T
/** imply if the page has next page */ c|(J%@B)
privateboolean hasNextPage; cIQbu#[@
f _$hK9I
/** the number of every page */ 71>,tq
privateint everyPage; ~1E!Co
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/** the total page number */ %6%mf>Guf
privateint totalPage; QVJpX;u
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/** the number of current page */ &ds+9A
privateint currentPage; xMNQT.A
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/** the begin index of the records by the current $U.|
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query */ pdR\Ne0P*
privateint beginIndex; ,Jh#$mil
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=.CiKV$E
/** The default constructor */ N*hV/"joZ
public Page(){ l$pz:m]Id
,}]v7DD
} Sgv_YoD?-
]{#=WTp]
/** construct the page by everyPage VBix8|
* @param everyPage Tg"? TZO~
* */ #;~HoOK*#
public Page(int everyPage){ 99`w'Nlk
this.everyPage = everyPage; U]gUGD!5x
} ZfX$q\7
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/** The whole constructor */ :N _]*>
public Page(boolean hasPrePage, boolean hasNextPage, =cZ24I
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int everyPage, int totalPage, %cg| KB"l
int currentPage, int beginIndex){ PuREqa\_[
this.hasPrePage = hasPrePage; Ex
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this.hasNextPage = hasNextPage; ~
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this.everyPage = everyPage; \QC{38}
this.totalPage = totalPage; `_ 1~[t
this.currentPage = currentPage; .4R.$`z4
this.beginIndex = beginIndex; =k.%#h{
} ZIa,pON
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/** k9OGnCW\
* @return {pH# zs4Y
* Returns the beginIndex. [.fh2XrVM
*/ &K60n6q{aQ
publicint getBeginIndex(){ #+l`tj4b/
return beginIndex; ,lA@C2c
} 2[Lv_<i|
19]19_-
/** 3.?be.cq
* @param beginIndex 18sc|t
* The beginIndex to set. cjPXrDl{\
*/ I/tMFg
publicvoid setBeginIndex(int beginIndex){ 7~QI4'e
this.beginIndex = beginIndex; eNK
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} $~.YB\3
4\&Y;upy+
/** iOURS
* @return WM
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* Returns the currentPage. ?=M?v;8
*/ ? /z[Jx.
publicint getCurrentPage(){ lUs$I{2_
return currentPage; -C
q;
} D1xGUz2r
0,t%us/q
/** I61S0lz/
* @param currentPage 950N\Y@u
* The currentPage to set. ALTOi?
*/ ~h@@y5<4
publicvoid setCurrentPage(int currentPage){ (4L/I
this.currentPage = currentPage; ?x #K:a?
} KN|<yF
f+ceL'fr
/** +`Z1L\gmA
* @return jn V=giBu
* Returns the everyPage. ja_8n["z
*/ WMa0L&C~v
publicint getEveryPage(){ nL:&G'd
return everyPage; S"Cz.
bv
} p5fr}#en
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/** #,d~t
* @param everyPage K4!-%d$
* The everyPage to set. }~I!'J#)
*/ h$l/wn
publicvoid setEveryPage(int everyPage){ f)/Z7*Z
this.everyPage = everyPage; {]R'U/
} .Ix3wR9
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/** \#9LwC"8;
* @return :DN!1~ZtW
* Returns the hasNextPage. 1(?4*v@B
*/ r<+C,h;aww
publicboolean getHasNextPage(){ o]e,5]
return hasNextPage; N6y9'LGG`
} jfxNV2[
hC:'L9Y
/** fc9;ZX7
* @param hasNextPage X1|
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* The hasNextPage to set. 7s|'NTp
*/ g<:Lcg"u
publicvoid setHasNextPage(boolean hasNextPage){ ?gE=hh
this.hasNextPage = hasNextPage; XQ]K,# i
} h&<"jCjL
p&<Ssc
/** \]tBwa
* @return Hy.u6Jt*/
* Returns the hasPrePage. F(G..XJQ
*/ p/h\QG1
publicboolean getHasPrePage(){ ,"%C.9a
return hasPrePage; TrjyU
} +K4XMf
) O0Cz n
/** KUI{Z I
* @param hasPrePage 7> Z| K
* The hasPrePage to set. ,MY7h8V/
*/ OdzeHpH3g
publicvoid setHasPrePage(boolean hasPrePage){ sfM"!{7
this.hasPrePage = hasPrePage; )(}[S:`
} ?XBdBR_"^
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/** @Kpm&vd(
* @return Returns the totalPage. U%q)T61
* %rW}x[M%w?
*/ `a83RX_\
publicint getTotalPage(){ F\:~^`
return totalPage; I5Vn#_q+b
} @ st>#]i4
-$d?e%}#
/** ^h[6{F~J
* @param totalPage O=0p}{3l
* The totalPage to set. -^@FZR^Y
*/ 7+jxf[(XQ
publicvoid setTotalPage(int totalPage){ xIM,0xM2
this.totalPage = totalPage; &;BhL%)}
} )&c2+Y@
!nmZ"n|}p
} ;d?BVe?
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 uyj!$}4
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个PageUtil,负责对Page对象进行构造: VUP|j/qD
java代码: FnGKt\
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/*Created on 2005-4-14*/ ql?w6qFs]
package org.flyware.util.page; {cdICWy(F3
_}{KS, f]0
import org.apache.commons.logging.Log; s< tG
import org.apache.commons.logging.LogFactory; ,:S#gN{U
d6i}xnmC
/** [@K'}\U^+
* @author Joa }?m0bM
* +)c<s3OCE
*/ !)M}(I}
publicclass PageUtil { 6#=Iv X4
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privatestaticfinal Log logger = LogFactory.getLog A}(xH`A
iM .yen_vp
(PageUtil.class); XDK Me}
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/** X}#vt?mu
* Use the origin page to create a new page 1d<?K7%^
* @param page )!(gS,
* @param totalRecords (?Ku-k
* @return 7w73,r/D8A
*/ bdrE2m
publicstatic Page createPage(Page page, int <Sot{_"li
l0&Fm:))k
totalRecords){ ~&:-c v
return createPage(page.getEveryPage(), F=F84_+K
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page.getCurrentPage(), totalRecords); aZf/WiR2
} *)[fGxz
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/** C6ql,hR^h`
* the basic page utils not including exception =p|IWn{P
GW
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handler g9C-!X-<T
* @param everyPage 'v'[_(pq
* @param currentPage F6vsU:TfB
* @param totalRecords kQI'kL8>
* @return page
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*/ Q
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publicstatic Page createPage(int everyPage, int gLMb,buqC
**P P
currentPage, int totalRecords){ o?]Q&,tO
everyPage = getEveryPage(everyPage); D[^K0<-Z
currentPage = getCurrentPage(currentPage); g?v/u:v>W
int beginIndex = getBeginIndex(everyPage, .i\FK@2
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currentPage); @
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int totalPage = getTotalPage(everyPage, ,{IDf
n\9IRuYO
totalRecords); nZiwR4kM
boolean hasNextPage = hasNextPage(currentPage, xkf2;
N5 sR
totalPage); <=CABWO.
boolean hasPrePage = hasPrePage(currentPage);
@Mg&T$
dr#%~I
returnnew Page(hasPrePage, hasNextPage, fFEB#l!oUb
everyPage, totalPage, dLqBu~*
currentPage, :V$\y up
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beginIndex); -[!t=qi
} K1YxF
"}
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privatestaticint getEveryPage(int everyPage){ ['>ZC3?"h
return everyPage == 0 ? 10 : everyPage; b1^wK"#
} /nv*OKS|
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privatestaticint getCurrentPage(int currentPage){ 4SUzR\
return currentPage == 0 ? 1 : currentPage; z,ryY'ua/I
} UvMkL
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privatestaticint getBeginIndex(int everyPage, int _{): w~zi
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currentPage){ =LY`K#
return(currentPage - 1) * everyPage; 4'3;{k$z
} Qu<6X@+5
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privatestaticint getTotalPage(int everyPage, int v?8i;[
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totalRecords){ qu#xc0?
int totalPage = 0; VZ IY=Q>g
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if(totalRecords % everyPage == 0) l(x0d
totalPage = totalRecords / everyPage; bGB$a0
else K%`]HW@I{
totalPage = totalRecords / everyPage + 1 ; L!Tvz(_7f6
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return totalPage; W'Ew!]Q3
} ic}TiTK
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privatestaticboolean hasPrePage(int currentPage){ W=g'Xu!|!2
return currentPage == 1 ? false : true; T_s09Wl
} xC5Pv">
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privatestaticboolean hasNextPage(int currentPage, jLn#%Ia}
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int totalPage){ bLWY Tj
return currentPage == totalPage || totalPage == #?\(l%
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0 ? false : true; R<I#.
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} &=S:I!9;;
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} du'`&{_/
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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。 569p/?
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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 PPFt p3C
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做法如下: "doiD=b
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 B#IUSHC
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的信息,和一个结果集List:
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java代码: qe(gKKA%q
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/*Created on 2005-6-13*/ }=\?]9`
package com.adt.bo; \p.yR.
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import java.util.List; m3o -p
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import org.flyware.util.page.Page; \6MM7x(U3
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/** cK\
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* @author Joa p/nATvh$
*/ |By[ev"Kh%
publicclass Result { MCEHv}W
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private Page page; )qMbk7:v\
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private List content; k{vbi-^6rf
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/** /
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* The default constructor <)!,$]S
*/ +XO\#$o>W
public Result(){ OE0G*`m
super(); ;/Z-|+!IJt
} +a N8l1
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/** vK+reXE
* The constructor using fields ,m]5j_< }
* w< Xwz`O
* @param page ^<-r57pz
* @param content eBxm
*/ *-Yw%uR
public Result(Page page, List content){ ?$)5NQB%
this.page = page; )kI**mI}
this.content = content; 2'- "&d+O
} ti%RE:*
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/** KgkRs?'z
* @return Returns the content. AnX<\7bc}
*/ K.mxF,H
publicList getContent(){ F{a;=h#@Q
return content; 3BCD0
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} MomHSv Q\
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/** O8bxd6xb
* @return Returns the page. lTq"j?#E]m
*/ 3Y2~HuM
public Page getPage(){ G'G8`1Nj
return page; aif;h!
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} #L+:MA7H
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/** 9>9EZ?4m
* @param content io+V4m
* The content to set. JJtx `@Bc
*/ ]'(D*4
public void setContent(List content){ q{Z#}|km#
this.content = content; -GCo`PR?b
} |SjRss:i+
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/** Is7BJf
* @param page ySmbX
* The page to set. oXnaL)Rk
*/ h5@GeYda
publicvoid setPage(Page page){ "hf
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this.page = page; *$vH]>)p
} ?![[la+f
} A'KH_])
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2. 编写业务逻辑接口,并实现它(UserManager, <ErX<(0`ig
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UserManagerImpl) -U=Ci
java代码:
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/*Created on 2005-7-15*/ IQ
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package com.adt.service; ;Y^'$I2fR#
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import net.sf.hibernate.HibernateException; D=#RQ-
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import org.flyware.util.page.Page; K"0IW A
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import com.adt.bo.Result; hL&$` Q
jb.H[n,\
/** g|>LT_
* @author Joa 5.9<g>C
*/ Db,"Gl
publicinterface UserManager { P0n1I7|
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public Result listUser(Page page)throws }uZs)UQ|$
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HibernateException; vQljxRtW
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} P]43FPb
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java代码: ]4l2jY
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/*Created on 2005-7-15*/ l6/VJ~(}'
package com.adt.service.impl; q>$MqKWM
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import java.util.List; "b} mVrFh
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import net.sf.hibernate.HibernateException; lG7PM^Eb
.^Sglo
import org.flyware.util.page.Page; ngo> ^9/8
import org.flyware.util.page.PageUtil; s#9q3JV0
srGOIK.
import com.adt.bo.Result; ?QOU9"@+B
import com.adt.dao.UserDAO; H7zN|NdNw
import com.adt.exception.ObjectNotFoundException; vMT f^V
import com.adt.service.UserManager; s1:Wrz?4
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/**
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* @author Joa 2J7|y\N,
*/ F]\
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publicclass UserManagerImpl implements UserManager { h?mDtMCw2
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private UserDAO userDAO; XO+BZB`F
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/** \SWTP1
* @param userDAO The userDAO to set. F9fLJol
*/ )?F&`+
publicvoid setUserDAO(UserDAO userDAO){ ,
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this.userDAO = userDAO; 2n<Mu Q]
} \|HEe{nA
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/* (non-Javadoc) aAg Qv*
* @see com.adt.service.UserManager#listUser a(gXvgrf[
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(org.flyware.util.page.Page) &jE\D^>ko
*/ 9&lemz
public Result listUser(Page page)throws 1}(22Q;
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HibernateException, ObjectNotFoundException { )DgXsT
int totalRecords = userDAO.getUserCount(); y )QLR<wf
if(totalRecords == 0) zI`I
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throw new ObjectNotFoundException 4V@%Y,:ee
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("userNotExist"); }Fe6L;^;
page = PageUtil.createPage(page, totalRecords); eZ'8JU]
List users = userDAO.getUserByPage(page); :u>RyKu|&R
returnnew Result(page, users); Nk'<*;e
} +A}t_u3<
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} TRhM xH
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]
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询,接下来编写UserDAO的代码: 67j kU!
3. UserDAO 和 UserDAOImpl: C QkY6
java代码: .?Eb{W)^br
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/*Created on 2005-7-15*/ PmuG(qg
package com.adt.dao; };Q}C0E
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import java.util.List; 7`|'Om?'
G5}_NS/
import org.flyware.util.page.Page; 7-744wV}Z
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import net.sf.hibernate.HibernateException; h FU8iB`Q
de:@/-|
/** hek+zloB+
* @author Joa ?8~l+m6s$
*/ 9g6$"',H
publicinterface UserDAO extends BaseDAO { |`T7}U
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publicList getUserByName(String name)throws HPtMp#`T
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HibernateException; "r^RfZ;
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publicint getUserCount()throws HibernateException; f^pBXz9&=
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publicList getUserByPage(Page page)throws b|i4me@
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HibernateException; bxE~tsM"@Y
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} [4"(\r\f
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java代码: ^q-%#
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/*Created on 2005-7-15*/ T@1;Nbz]
package com.adt.dao.impl; m*
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import java.util.List; Kw-<