Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 b IS3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @kq~q;F
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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 G^Z
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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 3Pb]Of#
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分页支持类: #0i] g)
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java代码: h{&X`$
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package com.javaeye.common.util; 0st)/\
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import java.util.List; **zh>Y}6
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publicclass PaginationSupport { D@M
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publicfinalstaticint PAGESIZE = 30; 4 Ar\`{c>
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privateint pageSize = PAGESIZE; B&tU~
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privateList items; dkz79G}e
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privateint totalCount; hkSK;
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privateint[] indexes = newint[0]; kfod[*3
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privateint startIndex = 0; :/Zy=F9:
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public PaginationSupport(List items, int &&N]u e@>
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totalCount){ N8<Wm>GLX~
setPageSize(PAGESIZE); )czuJ5
setTotalCount(totalCount); 9~6FWBt
setItems(items); ^Fy{Q*p`(
setStartIndex(0); Qx9lcO_
} a0vg%Z@!
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public PaginationSupport(List items, int Vb=Oz
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totalCount, int startIndex){ H.8f-c-4we
setPageSize(PAGESIZE); JN{.-k4Ha
setTotalCount(totalCount); l8"
setItems(items); NH?q/4=I0W
setStartIndex(startIndex); ?a8 o.&`l
} yQ33JQr
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public PaginationSupport(List items, int MEOVw[hO
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totalCount, int pageSize, int startIndex){ 63ig!-9F
setPageSize(pageSize); 6cCC+*V{
setTotalCount(totalCount); ^ Vl{IsY
setItems(items); {8NnRnzU
setStartIndex(startIndex); DE GEr-
} 1-@[th
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publicList getItems(){ }Q 7~tu
return items; Et\z^y
} -t92! O
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publicvoid setItems(List items){ 'USol<
this.items = items; hOI|#(-
} R$'0<y8E*]
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publicint getPageSize(){ l;4},N
return pageSize; L-7?:
} )qGw!^8
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publicvoid setPageSize(int pageSize){ *\?tW]8<
this.pageSize = pageSize; eOZ0L1JM!
} MGH(= w1
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publicint getTotalCount(){ WU:~T.Su
return totalCount; [L.+N@M
} G(LGa2;Zg
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publicvoid setTotalCount(int totalCount){ ?v]EXV3
if(totalCount > 0){ Pt/dH+r`%
this.totalCount = totalCount; 5ua`5Hb;
int count = totalCount / (#Vkk]-p
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pageSize; ar-N4+!@
if(totalCount % pageSize > 0) %3L4&W_T
count++; %P!6cyQS
indexes = newint[count]; |hsg=LX
for(int i = 0; i < count; i++){ [.M<h^xrB
indexes = pageSize * ?a~59!u
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} }9w?[hXW"
}else{ PU0Ha
this.totalCount = 0; o6JCy\Bx
} IMaa#8,
} 0w'%10"&U+
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publicint[] getIndexes(){ Te%2(w,B
return indexes; 3P{
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publicvoid setIndexes(int[] indexes){ 3b1;f)t
this.indexes = indexes; LvlVZjT
} |@{4zoP_N
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publicint getStartIndex(){ R`? '|G]P
return startIndex; jQ &$5&o
} SE%B&8ZD
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publicvoid setStartIndex(int startIndex){ ('H[[YODh
if(totalCount <= 0) AE1EZ#
this.startIndex = 0; (*{Y#XD{
elseif(startIndex >= totalCount) {)E)&lL
this.startIndex = indexes 'CE3
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[indexes.length - 1]; ~b.C[s
elseif(startIndex < 0) {q=(x]C
this.startIndex = 0; 1SddZ5
else{ MeD}S@H
this.startIndex = indexes aRPpDSR?l
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[startIndex / pageSize]; G}!dm0s$
} 4x.1J
} PQ6.1}
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publicint getNextIndex(){ jNKu5"HB
int nextIndex = getStartIndex() + Q\WH2CK
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pageSize; wR)U&da`@
if(nextIndex >= totalCount) b`?$;5
return getStartIndex(); oMM+af
else ZCdlTdY
return nextIndex; <g/Z(<{wor
} y~,mIM$[@
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publicint getPreviousIndex(){ 5](-(?k}~
int previousIndex = getStartIndex() - 6Vr:?TI7
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pageSize; N~c Y ~a
if(previousIndex < 0) nnP]x [
return0; ^[]q/v'3m!
else 3em&7QM
return previousIndex; [1OX:O|
} rCOH*m&
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} >A'Q9Tia;
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抽象业务类 m tPmVze
java代码: cV=0)'&<`_
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/** Wq5 Nc
* Created on 2005-7-12 @xKfqKoqg
*/ 7w}PYp1Z'~
package com.javaeye.common.business; N0]C?+
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import java.io.Serializable; 5somoV B
import java.util.List; Wt$" f
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import org.hibernate.Criteria; a]JQZo1$
import org.hibernate.HibernateException; lCyBdY9n
import org.hibernate.Session; hUL5V1-j
import org.hibernate.criterion.DetachedCriteria; R^[b
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import org.hibernate.criterion.Projections; [(*ObvEF
import L[Z
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org.springframework.orm.hibernate3.HibernateCallback; H1!u1k1nl
import ;nzzt~aCC
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org.springframework.orm.hibernate3.support.HibernateDaoS ],!7S"{97
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upport; ^p@R!228
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import com.javaeye.common.util.PaginationSupport; `$kKTc:f
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public abstract class AbstractManager extends #Cj$;q{!
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HibernateDaoSupport { )GbVgYkk
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privateboolean cacheQueries = false; A>0wqT
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privateString queryCacheRegion; @ V_@r@A
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publicvoid setCacheQueries(boolean M1>2Q[h7
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cacheQueries){ }&E'ox<S
this.cacheQueries = cacheQueries; erhxZ|."P
} P~6QRm
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publicvoid setQueryCacheRegion(String =N,ahq
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queryCacheRegion){ rM|] }M=_V
this.queryCacheRegion = ~~8?|@V
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queryCacheRegion; be@\5
} \J)ffEKIp
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publicvoid save(finalObject entity){ 0 It[Pa qG
getHibernateTemplate().save(entity); D%WgE&wtM
} XIS.0]~
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publicvoid persist(finalObject entity){ ,_G((oS40
getHibernateTemplate().save(entity); QTy xx
} f@G3,u!]i
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publicvoid update(finalObject entity){ :J
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getHibernateTemplate().update(entity); Zze(Ik
} |i/Iv
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publicvoid delete(finalObject entity){ q? 9x0L
getHibernateTemplate().delete(entity); TB oN8cB}
} Uk2U:
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publicObject load(finalClass entity, Ke5fe#
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finalSerializable id){ x)^/3
return getHibernateTemplate().load uU|fCwQt
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(entity, id); z~Ec *
} iC$mb~G
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publicObject get(finalClass entity, |afzW=8'
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finalSerializable id){ mbZS J
return getHibernateTemplate().get $L@os2
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(entity, id); T({]fc!c
} i&%/]Nq
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publicList findAll(finalClass entity){ a4B#?p
return getHibernateTemplate().find("from H&yK{0H
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" + entity.getName()); ,j'>}'wG)
} 6)@Y 41H]C
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publicList findByNamedQuery(finalString [|:kS
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namedQuery){ *8a8Ng
return getHibernateTemplate CP%?,\
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().findByNamedQuery(namedQuery); 5LIbHSK
} gM5`UH|
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publicList findByNamedQuery(finalString query,
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finalObject parameter){ ;q3"XLV(T[
return getHibernateTemplate P:p@Iep
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().findByNamedQuery(query, parameter); pyf/%9R:d
} }uCC~ <^
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publicList findByNamedQuery(finalString query, j9bn|p$DA
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finalObject[] parameters){ BS6UXAf{|Z
return getHibernateTemplate @77%15_Jz
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().findByNamedQuery(query, parameters); [VsTyqV a
} ~S$\ PG4
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publicList find(finalString query){ ~zcHpxO^W
return getHibernateTemplate().find 4"=(kC~~
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(query); U^xz>:~
} Jxq;Uu9
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publicList find(finalString query, finalObject 65~X!90k
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parameter){ ~0^d-,ZD5
return getHibernateTemplate().find h"/y$
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(query, parameter); {e1akg.
} JIA'3"C
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public PaginationSupport findPageByCriteria mfI>1W(
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(final DetachedCriteria detachedCriteria){ R)<PCe`vf
return findPageByCriteria +@j@# ~=K
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); y\xa<!:g
} v Mi&0$
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public PaginationSupport findPageByCriteria 6UXDIg=
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(final DetachedCriteria detachedCriteria, finalint q>E[)\+y
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startIndex){ o~(/Twxam
return findPageByCriteria q0>@!1Wb
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(detachedCriteria, PaginationSupport.PAGESIZE, 74c[m}'S
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startIndex); _@gd9Fi7J
} qoo+=eh!
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public PaginationSupport findPageByCriteria k^Gf2%k
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(final DetachedCriteria detachedCriteria, finalint iz0GL&<
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pageSize, ?|`Ba-
finalint startIndex){ n'42CE
return(PaginationSupport) 5N_w(B
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getHibernateTemplate().execute(new HibernateCallback(){ 1h[xVvo<L
publicObject doInHibernate SFiK_;
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(Session session)throws HibernateException { KH~o0 W
Criteria criteria = 'Y%@fZf x
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detachedCriteria.getExecutableCriteria(session); aYBc)LCd
int totalCount = w`Ss MI
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((Integer) criteria.setProjection(Projections.rowCount j$5S_]2
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()).uniqueResult()).intValue(); =Ay'\j
criteria.setProjection ]8c%)%Vi
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(null); hbOyrjanx
List items = NhgzU+)+
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criteria.setFirstResult(startIndex).setMaxResults ,*r}23
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(pageSize).list(); :9O"?FE
PaginationSupport ps = `/4R$E{
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new PaginationSupport(items, totalCount, pageSize, / p PSo
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startIndex); X;vfbF
return ps; ~:ldGfb|
} *>#mI/#}
}, true); 'Wv`^{y <^
} ;L{#TC(]J]
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public List findAllByCriteria(final + bU*"5"
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DetachedCriteria detachedCriteria){ 'PBuf:9lN
return(List) getHibernateTemplate 0&@pD`K e
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().execute(new HibernateCallback(){ 6HK
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publicObject doInHibernate =rB=! ;
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(Session session)throws HibernateException { eM1=r:jgE
Criteria criteria = &{5v[:$
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detachedCriteria.getExecutableCriteria(session); O.HaEg/-
return criteria.list(); v[*&@aW0n
} MB:VACCr
}, true); 2l YA% n
} U^@8ebv
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public int getCountByCriteria(final O9_S"\8]@
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DetachedCriteria detachedCriteria){ ui[E,W~
Integer count = (Integer) ' thEZ
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getHibernateTemplate().execute(new HibernateCallback(){ @8;0p
publicObject doInHibernate Ug1[pONk
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(Session session)throws HibernateException { d${RZ}/
Criteria criteria = IcDAl~uG
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detachedCriteria.getExecutableCriteria(session); $X;wj5oj
return waYH_)Zx
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criteria.setProjection(Projections.rowCount 1;Q>B>6
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()).uniqueResult(); :-.K.Ch|:
} +kXj+2
}, true); CL%+`c0
return count.intValue(); EK
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} DJu&l
} OSDx
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用户在web层构造查询条件detachedCriteria,和可选的 eKT'd#o2R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 vvDaL$
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PaginationSupport的实例ps。 4NN81~v 4
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ps.getItems()得到已分页好的结果集 :/1/i&a
ps.getIndexes()得到分页索引的数组 mK);NvJ!
ps.getTotalCount()得到总结果数 JBCJVWUt
ps.getStartIndex()当前分页索引 {;kH&Pp
ps.getNextIndex()下一页索引 :AzP3~BI
ps.getPreviousIndex()上一页索引 F:P&hK
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R06zca
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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 y9>?
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一下代码重构了。 2S{IZ]
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类: @uWPo2
java代码: JuD$CHg;#
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/*Created on 2005-4-14*/ :2\H>^uV
package org.flyware.util.page; s)e' }y
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/** N-+`[8@(P<
* @author Joa 6kc/
* #f 4"
*/ k/|j e~$
publicclass Page { 3cp"UU}.
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/** imply if the page has previous page */ "* Qwaq_
privateboolean hasPrePage; v8<MAq
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/** imply if the page has next page */ QCI-YJ&o
privateboolean hasNextPage; qZ:-- ,9+
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/** the number of every page */ Hsoe?kUHF
privateint everyPage; wJ|wAS
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/** the total page number */ /^d!$v
privateint totalPage; jq4{UW'
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/** the number of current page */ 'yWv @)
privateint currentPage; Q>FuNdUk
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/** the begin index of the records by the current ]('isq,P
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query */ /y\KLa
privateint beginIndex; Ff\U]g
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/** The default constructor */ ZA;wv+hF=
public Page(){ )I`6XG
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} O*<,lq 0K
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/** construct the page by everyPage qP"<vZ
* @param everyPage *+E9@r=HF
* */ D\:~G}M
public Page(int everyPage){ sf|[oD
this.everyPage = everyPage; TV>UD
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} CVi3nS5Yl
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/** The whole constructor */ D [#1~M
public Page(boolean hasPrePage, boolean hasNextPage, qYMTud[Vf
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int everyPage, int totalPage, V0]6F
int currentPage, int beginIndex){ Ef;OrE""
this.hasPrePage = hasPrePage; @Y#{[@Hp%
this.hasNextPage = hasNextPage; ypuW}H%`
this.everyPage = everyPage; $=j}JX}z
this.totalPage = totalPage; A@@Z?t.
this.currentPage = currentPage; Hm?zMyO.k
this.beginIndex = beginIndex; j
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} S*o%#ZJN
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/** /lQGFLZL
* @return r+BPz%wM=O
* Returns the beginIndex. HDyus5g
*/ K4vl#*qn
publicint getBeginIndex(){ O; qerE?i`
return beginIndex; (~r"N?`
} o3hsPzOQx
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/** +G3&{#D
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* @param beginIndex 1RtbQ{2F;
* The beginIndex to set. a&Ti44a[
*/ rZDmZm?=
publicvoid setBeginIndex(int beginIndex){ ,$,6%"'"
this.beginIndex = beginIndex; 29?{QJb
} /x6,"M[97
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/** xj/ +Z!,9
* @return nQc]f*
* Returns the currentPage. Ojx1IL
*/ vZM.gn
publicint getCurrentPage(){ qbjLTE=
return currentPage; zR'lQ<u
} /5@V $c8
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/** ?~e 8:/@
* @param currentPage d/8I&{.
* The currentPage to set. JDi|]JY
*/ 9PA\Eo|Yb
publicvoid setCurrentPage(int currentPage){ F/\w4T
this.currentPage = currentPage; b!Q|0X.?
} j*m7&wOE
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/** ZJ9J*5!C
* @return l@FPTHq
* Returns the everyPage. &46h!gW
*/ n>tYeN)F<
publicint getEveryPage(){ sXm/+I^
return everyPage; [YY[E 7
} x4cP%{n
zV\\T(R)
/** QvK-3w;=
* @param everyPage m4{F-++dk
* The everyPage to set. yz}Agc4.I
*/ F:.rb
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publicvoid setEveryPage(int everyPage){ (gQ^jmZPG
this.everyPage = everyPage; DFKU?#R
} wRL=9/5(8
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/** 33lD`4i+
* @return <wge_3W#
* Returns the hasNextPage. u@\]r 1
*/ H gMLh*
publicboolean getHasNextPage(){ +53 Tf
return hasNextPage; 'W5r(M4U
} ZPWY0&9
~^QL"p:5|
/** 3jIi$X06
* @param hasNextPage =dD<[Iz6
* The hasNextPage to set. ?b0 VB
*/ MR/jM@8
publicvoid setHasNextPage(boolean hasNextPage){ (MiEXU~v
this.hasNextPage = hasNextPage; TC1#2nE&T
} k:nR'TI
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/** 8BC F.y
* @return JPQ[JD^]
* Returns the hasPrePage. W is_N3M
*/ 'v.i' 6
publicboolean getHasPrePage(){ )A9K9pZj
return hasPrePage; D.H$4[u;j
} wt4uzg8
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/** rxu
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* @param hasPrePage
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* The hasPrePage to set. &B\tcF
*/ F gM<2$h
publicvoid setHasPrePage(boolean hasPrePage){ _D:#M
this.hasPrePage = hasPrePage; Z-`j)3Y
} wkK61ah6
0[@9f1Nk4
/** c#M'Mye
* @return Returns the totalPage. $:kG>R@\t
* \TSt
*/ 3!M;Z7qF]
publicint getTotalPage(){ beFVjVVHq
return totalPage; rr fL[
} U7d%*g
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/** @O#4duM4Qz
* @param totalPage CZ*c["x2
* The totalPage to set. %-!ruc"}
*/ w*`5b!+/
publicvoid setTotalPage(int totalPage){ ru,]!YPJE2
this.totalPage = totalPage; 5;5;bBo~
} mAh0xgm
/gZrnd?
} Qhb].V{utV
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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 K2,oP )0.Y
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个PageUtil,负责对Page对象进行构造: D4[1CQ@}4D
java代码: ItGi2'}
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/*Created on 2005-4-14*/ ri&B%AAc
package org.flyware.util.page; 2bBTd@m4
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import org.apache.commons.logging.Log; Cdl#LVqs
import org.apache.commons.logging.LogFactory; %1fH-:c=C0
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/** $lmbeW[0
* @author Joa [{e[3b*M|
* &/*XA
*/ }Z*@EWc>
publicclass PageUtil { PLR[nB7K
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privatestaticfinal Log logger = LogFactory.getLog v#
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@K/}Ob4
(PageUtil.class); =vLeOX
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/** =8S*t5
* Use the origin page to create a new page
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* @param page +h^>?U,
* @param totalRecords |
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* @return $},Y)"mI
*/ .C(Ir
publicstatic Page createPage(Page page, int ~TwjcI*/
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totalRecords){ P]:r'^Yn
return createPage(page.getEveryPage(), 44 ,:@
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page.getCurrentPage(), totalRecords); +c5z-X$^]
} <wUDcF
}N^.4HOS8
/** h}fz`ti U
* the basic page utils not including exception d)F~)}TFM
&
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handler o5KpiibFM
* @param everyPage XL>v$7`#
* @param currentPage @G< J+pm
* @param totalRecords BYt#aqf
* @return page :iJ+ImBpK
*/ nPh5(&E
publicstatic Page createPage(int everyPage, int w1B!z
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currentPage, int totalRecords){ @ SaU2
everyPage = getEveryPage(everyPage); ScU?T<u:i
currentPage = getCurrentPage(currentPage); W|J8QNL?jm
int beginIndex = getBeginIndex(everyPage, ?{l}35Q.@
{h/[!I`
currentPage); U8L%=/N>B
int totalPage = getTotalPage(everyPage, DJ;il)^
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totalRecords); 8 hx4N
boolean hasNextPage = hasNextPage(currentPage, J'9hzag
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totalPage); (@*[^@ipV
boolean hasPrePage = hasPrePage(currentPage); tcyami6D4
t%Hg8oya
returnnew Page(hasPrePage, hasNextPage, xayo{l=uGv
everyPage, totalPage, wJM})O%SQ
currentPage, TUoEk
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beginIndex); asqbLtQ
} lPyGL-Q
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privatestaticint getEveryPage(int everyPage){ oLK-~[p
return everyPage == 0 ? 10 : everyPage; (`PgvBL:
} D@ut -J(.
eS(\E0%QI
privatestaticint getCurrentPage(int currentPage){ h^R EBPe
return currentPage == 0 ? 1 : currentPage; zu}oeAQc$
} _<pSCR0
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privatestaticint getBeginIndex(int everyPage, int ]V*s-och'
:U_k*9z}=
currentPage){ gSQq
return(currentPage - 1) * everyPage; }&A!h
} $5kb3x<W
vgY )
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privatestaticint getTotalPage(int everyPage, int <uZ
r.X
vw VeHjR
totalRecords){ @\0U`*]^)
int totalPage = 0; 0`%eP5
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if(totalRecords % everyPage == 0) yJ*`OU#
totalPage = totalRecords / everyPage; 21'I-j
else tE3#Uq
totalPage = totalRecords / everyPage + 1 ; 5/Viz`hsz
g&eIfm
return totalPage; i]&C=X
} !J`>;&
5%,5Xe4p
privatestaticboolean hasPrePage(int currentPage){ E~vM$$O$
return currentPage == 1 ? false : true; tY~gn|M
} .vsrZ_y?
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privatestaticboolean hasNextPage(int currentPage, u6^cLQO+
jp=z
^l
int totalPage){ F]]1>w*/0
return currentPage == totalPage || totalPage == xUl=N
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0 ? false : true; )H@"S]?7i"
} Vb^P{F
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} zOJ4I^^
KMC]<
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Q@]~O-
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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。 u#(VR]u\7
Y,BzBUWK
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 ZL/iX~}a'
{8+FxmH
做法如下: ROcI.tL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fA"N5qQI(
{l$DNnS
的信息,和一个结果集List: /)RyRS8c
java代码: ILi{5L
,z<J`n
E4;vC ?K{
/*Created on 2005-6-13*/ N{oi }i6
package com.adt.bo; ~[n]la
kaM=Fk=t
import java.util.List; zq]I"0Bi.
2I'gT$h
import org.flyware.util.page.Page; S -$ L2N
$ 9bIUJ
/** %oPW`r
* @author Joa m? 3!
*/ ;75m 9yGo
publicclass Result { %siBCjvo=
<Y%km[Mh
private Page page; 38ac~1HjE
Gy}WZ9{
private List content; }!_x\eq^
Jr|"QRC
/** ~,#zdm1r@
* The default constructor :
:;YS9e
*/ aumWU{j=
public Result(){ }%e"A4v
super(); %f[0&)1!.v
} B=dF\.&Z
]b5E_/P
/** eCejO59F9
* The constructor using fields Cj{+DXT
* p;8I@~dh
* @param page NTq#'O) f
* @param content 2@7f^be
*/ O7<- -
public Result(Page page, List content){ vG E;PwR
this.page = page; r 0mA
this.content = content; m~7[fgN2
} MU_8bK9m
i'XW)n
/** N
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* @return Returns the content. LPuc&8lGWf
*/ wXUP%i]i=
publicList getContent(){ O*qSc^ 9q
return content; Ml-GAkgG
} +]?/c>M
wWq(|"
/** [[vu#' bc
* @return Returns the page. W=QT-4
*/ }jL_/gvgy
public Page getPage(){ m.:2G
return page; h\qQ%|X
} Cu2eMUGt
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/** ~vL7$-:
* @param content <]:X
* The content to set. AQ}(v,DOb
*/ &P2tzY'
public void setContent(List content){ [K 5#4k
this.content = content; TNi4H:\
} SynL%Y9)|,
w_gFN%8
/** @^q|C&j
* @param page ;i;2cq
* The page to set. ucP"<,a
*/ <H; z4
publicvoid setPage(Page page){ b\{34z,
this.page = page; i sK_t*
} fRcs@yZnS
} f&=WgITa
FCr^D$_w
-_%8Q#"
5yA1<&z
3EY>XS
2. 编写业务逻辑接口,并实现它(UserManager, 30BFwNE
QaVxP1V#U
UserManagerImpl) Ca2He}r`
java代码: -'!K("
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hIXA.
AqqD!
/*Created on 2005-7-15*/ st7\k]J\
package com.adt.service; MC'2;,
ejFGeR
import net.sf.hibernate.HibernateException; NE~R&ym9
HQ187IwpTm
import org.flyware.util.page.Page; n0\k(@+k
r%:Q(|v?
import com.adt.bo.Result; X=1Po |
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/** /
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* @author Joa 7O.?I#
76
*/ t[r<&1[&
publicinterface UserManager { ^X?D4a|;#g
uT
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public Result listUser(Page page)throws _VjfjA<c8
*A^`[_y
HibernateException; T'W@fif
W5)R{w0`GD
} r
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$
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s^&Oh*SP*
=/#+,
java代码: _N @h
;q"Yz-3
~[N"Q|D3Y
/*Created on 2005-7-15*/ B2kKEMdGg
package com.adt.service.impl; $>M-oNeC
S6d&w6
import java.util.List; qOqU
CRUe:
Xn%ty@8
import net.sf.hibernate.HibernateException; H{d;,KfX
vvi[+$M
import org.flyware.util.page.Page; @$*LU:[
import org.flyware.util.page.PageUtil; &s{" Vc9]
yIq.
m=
import com.adt.bo.Result; %"jp':
import com.adt.dao.UserDAO; [X&VxTxr
import com.adt.exception.ObjectNotFoundException; Lu][0+-
import com.adt.service.UserManager; swTur
,N1I\f
/** /0_^Z2
* @author Joa cWU9mzsE
*/ *+UgrsRk
publicclass UserManagerImpl implements UserManager { E2nsBP=5C
rlpbLOG`
private UserDAO userDAO; \/8oua_)
1;E^3j$
/** .7K<9K +P
* @param userDAO The userDAO to set. llE_-M2gH
*/ P}re"<MD
publicvoid setUserDAO(UserDAO userDAO){ L|`(u
this.userDAO = userDAO; x
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f?
} 0XzrzT"&
O;6am++M@
/* (non-Javadoc) qib4DT$v-6
* @see com.adt.service.UserManager#listUser i]{-KZC
H[DBL
(org.flyware.util.page.Page) +EOd9.X\~
*/ +
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public Result listUser(Page page)throws {Q(R#$)5+
|Bhj L,
HibernateException, ObjectNotFoundException { %+bw2;a6
int totalRecords = userDAO.getUserCount(); +FBUB
if(totalRecords == 0) uLq%Nu
throw new ObjectNotFoundException O/ih9,
tj1M1s|a
("userNotExist"); Nu[0X
page = PageUtil.createPage(page, totalRecords); Q1
5h \!u
List users = userDAO.getUserByPage(page); it)!-[:bm
returnnew Result(page, users); )Kbz gmLr
} 3$n O@rOS
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} >"|"Gy (
^ fqco9^;
+#RqQ8\
K)&oDwk
L3J .Oh
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 r"hogmFD;
}{S pV
询,接下来编写UserDAO的代码: ]m=2 $mK
3. UserDAO 和 UserDAOImpl: q_b,3Tp
java代码: k.6gX<T
o/\f+iz7
5)=YTUCk
/*Created on 2005-7-15*/ XNaiMpp'
package com.adt.dao; ><DXT nt'x
>0AVs6&;v
import java.util.List; +6;1.5Tc
3q)y;T\yW
import org.flyware.util.page.Page; qgkC)
;hZ^zL
import net.sf.hibernate.HibernateException; x*a^msY%
7\<}378/^
/** HlgkW&