Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]8\I{LR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 g0tnt)]
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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 #y83tNev
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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 >#|%'Us
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。 _-TplGSO=c
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分页支持类: I "AjYv4R
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java代码: v.Ba
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package com.javaeye.common.util; |6*Bu1
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import java.util.List; :+ ,;5
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publicclass PaginationSupport { bV8+Eu
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publicfinalstaticint PAGESIZE = 30; eBrNhE-[G]
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privateint pageSize = PAGESIZE; [s>3xWZ+a
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privateList items; ?{S>%P A_B
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privateint totalCount; 2!^=G=H/
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privateint[] indexes = newint[0]; &:&89<C'
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privateint startIndex = 0; VI2lwE3
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public PaginationSupport(List items, int 4!/JN J
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totalCount){ y|5s
setPageSize(PAGESIZE); r)iEtT!p*
setTotalCount(totalCount); ~T1W-ig4[*
setItems(items); MxsLrWxm
setStartIndex(0); DXLXGvcM
} :<qe2Z5k
$Z@*!B^
public PaginationSupport(List items, int ?G,4N<]Nu
>!=@TK(~
totalCount, int startIndex){ G]'ah1W
setPageSize(PAGESIZE); ^c\O,*:
setTotalCount(totalCount); $+*nb4
setItems(items); VsQ|t/|#
setStartIndex(startIndex); ] 3{t}qY$A
} 5*YoK)2J
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public PaginationSupport(List items, int aOzIo-
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totalCount, int pageSize, int startIndex){ SyvoN,;Q
setPageSize(pageSize); i HD!v7d7
setTotalCount(totalCount); +Q5O$8i
setItems(items); *-T.xo
setStartIndex(startIndex); cE]z Tu?!
} b(*\4n
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publicList getItems(){ $Ll9ak}
return items; cc[(w
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} ~:a1ELqVw
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publicvoid setItems(List items){ u"v7shRp:
this.items = items; / FcRp ,"
} 9{u8fDm!
jrib"Bh3,
publicint getPageSize(){ U#3N90,N=
return pageSize; 9-42A7g^C
} X0.H(p#s
/ Q1*Vh4
publicvoid setPageSize(int pageSize){ 5)#j }`6
this.pageSize = pageSize; %B%_[<B
} 46:<[0Psl/
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publicint getTotalCount(){ ppAbG,7
return totalCount; 0?7yM:!l
} "V|Rq]_+%
V\L;EHtc$
publicvoid setTotalCount(int totalCount){ jx}&%p X
if(totalCount > 0){ P<]U
this.totalCount = totalCount; .WF"vUp
int count = totalCount / n7!T{+ge
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pageSize; $J7V]c*-b
if(totalCount % pageSize > 0) ?2<)
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count++; 8M5)fDu*?
indexes = newint[count]; Tv ``\<
for(int i = 0; i < count; i++){ hi8q?4jE
indexes = pageSize * c!Hz'W
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i; )4g_S?l=
} t<!m4Yd|#
}else{ fd)8lK[KJ"
this.totalCount = 0; R]"Zv'M(AM
} qezWfR`
} 6Og@tho
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publicint[] getIndexes(){ A0{xt*g
return indexes; t!?`2Z5
} uMcI'=
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publicvoid setIndexes(int[] indexes){ !<w6j-S
this.indexes = indexes; {<-s&%/r
} :\;9y3
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publicint getStartIndex(){ b<a3Ue%
return startIndex; O/~T+T%
} FQWjL>NB
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publicvoid setStartIndex(int startIndex){ YgEd%Z%4
if(totalCount <= 0) /~"-q
this.startIndex = 0; .eJKIck
elseif(startIndex >= totalCount) Vl5r~+$|
this.startIndex = indexes Igo`\JY
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[indexes.length - 1]; QV[&2&&^<<
elseif(startIndex < 0) yX
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this.startIndex = 0; D2ggFxqe
else{ a
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this.startIndex = indexes } 9@rhW
q`e0%^U
[startIndex / pageSize]; kepuh%KY[
} ().C
} #/qcp|m
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publicint getNextIndex(){ uz3cho'
int nextIndex = getStartIndex() + Y9abRrK
+R~]5Rxd
pageSize; }u^bTR?3
if(nextIndex >= totalCount) #]Vw$X_S
return getStartIndex(); X_PzK'#m
else DwBe_h .
return nextIndex; %pZT3dcK
} =]@Bc
7@
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publicint getPreviousIndex(){ 8r(Vz
int previousIndex = getStartIndex() - lO@-*m$
Vz mlKVE
pageSize; 2tz4Ag
if(previousIndex < 0) Rxy|Ag/I;V
return0; HVM%B{(
else I(6%'s2
return previousIndex; /qQx~doK
} |6AR!
ic G 9x
} P}6#s'07~
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抽象业务类 4f j}d.?
java代码: orJ|Q3c)d
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/** T)tr"<F5NP
* Created on 2005-7-12 [)`*k#.=
*/ yK{P%oh)
package com.javaeye.common.business; RlfI]uCDM
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import java.io.Serializable; &wNr2PHd#
import java.util.List; cJSNV*<
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import org.hibernate.Criteria; B~o3Z
import org.hibernate.HibernateException; ^ iu)vED
import org.hibernate.Session; Qz`evvH
import org.hibernate.criterion.DetachedCriteria; q`AsnAzo&
import org.hibernate.criterion.Projections; $;g*s?F*
import ceg\lE:8
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org.springframework.orm.hibernate3.HibernateCallback; _3
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import ]FR#ZvM>x
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org.springframework.orm.hibernate3.support.HibernateDaoS 7:~3B-Tb
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upport; :{w3l O
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import com.javaeye.common.util.PaginationSupport; z7fX!'3V
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public abstract class AbstractManager extends Va[&~lA)
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HibernateDaoSupport { #W:.Fsq
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privateboolean cacheQueries = false; n_sV>$f-u
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privateString queryCacheRegion; " "`z3-
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publicvoid setCacheQueries(boolean S*r }oX0
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cacheQueries){ # wn>S<
this.cacheQueries = cacheQueries; _WV13pnRu
} b?k,_;\
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publicvoid setQueryCacheRegion(String |QrVGm@2
; <- f
queryCacheRegion){ .9DhD=8aIO
this.queryCacheRegion =
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queryCacheRegion; u}'m7|)8
} d3oRan}z
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publicvoid save(finalObject entity){ Z){fie4WM
getHibernateTemplate().save(entity); iLdUus!
} x+sSmW
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publicvoid persist(finalObject entity){ KjA7x
getHibernateTemplate().save(entity); w^~s4Q_>>
} ;&b=>kPlZ
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publicvoid update(finalObject entity){ .:-*89c
getHibernateTemplate().update(entity); UXa%$gwFw
} >U:-U"rA?
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publicvoid delete(finalObject entity){ y] Q/(O
getHibernateTemplate().delete(entity); D$hK
} 0Dd8c\J
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publicObject load(finalClass entity, b#(QZ
<{V{2V#
finalSerializable id){ _)CCD33$
return getHibernateTemplate().load 45+kwo0
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(entity, id); g6q[
I8
} j1JdG<n
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publicObject get(finalClass entity, 2%l(qfN9
p,4S?cr>a
finalSerializable id){ j"0TAYmXwu
return getHibernateTemplate().get Dmtsu2o
%)}_OXWf:
(entity, id); ZA4sEVHW
} ^]LWcJ?"^!
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publicList findAll(finalClass entity){ 'pAq;2AA
return getHibernateTemplate().find("from Ud-c+, xX
B)DtJf
" + entity.getName()); wh]v{Fi'
} <.|]%7
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publicList findByNamedQuery(finalString O|;|7fCB\
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namedQuery){ ]xJ2;{JWsO
return getHibernateTemplate J@Nq
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().findByNamedQuery(namedQuery); >+BLD
} BBoVn^Z*R
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publicList findByNamedQuery(finalString query, 9@(V!G
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finalObject parameter){ ?cr^.LV|h^
return getHibernateTemplate 7*&q"
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().findByNamedQuery(query, parameter); -A8CW9|mk
} ~:A=o?V2
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publicList findByNamedQuery(finalString query, jW|M)[KJN
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finalObject[] parameters){ CJLfpvV
return getHibernateTemplate j&?@:Zg v
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().findByNamedQuery(query, parameters); q-0(
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} CwzDkr&QC_
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publicList find(finalString query){ ;#2yF34gv
return getHibernateTemplate().find ma2-66M~j
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(query); k5Df97\s
} {Pi]i?
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publicList find(finalString query, finalObject ;x=0+0JD
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parameter){ s4\_%je<v
return getHibernateTemplate().find \ N]2V(v
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(query, parameter); <yEd'Z
} [tz}H&
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public PaginationSupport findPageByCriteria mvW,nM1Y
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(final DetachedCriteria detachedCriteria){ "M:0lUy
return findPageByCriteria jTz~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &p^8zE s
} 20RI S j
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint w`K=J!5y2g
(ft$ R?
startIndex){ [,ns/*f3R
return findPageByCriteria w>gB&59r
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(detachedCriteria, PaginationSupport.PAGESIZE, Hk|wO:7Be
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startIndex); GZqy.AE,
} xrl!$xE
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public PaginationSupport findPageByCriteria ],ISWb
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(final DetachedCriteria detachedCriteria, finalint L(qQ,1VY
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pageSize, PzDekyl
finalint startIndex){ ]PjJy/vkjj
return(PaginationSupport) (\NZ)Ys
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getHibernateTemplate().execute(new HibernateCallback(){ >FM2T<.;
publicObject doInHibernate ;V\l,
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(Session session)throws HibernateException { ":N
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Criteria criteria = uz;z+Bd^
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detachedCriteria.getExecutableCriteria(session); loFApBD=$^
int totalCount = sDnXgCcS!
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((Integer) criteria.setProjection(Projections.rowCount #Rcb
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DF!*S{)
()).uniqueResult()).intValue(); 0_faJjTbP;
criteria.setProjection <mdHca
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(null); vCS D1~V_
List items = P<A_7Ho
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criteria.setFirstResult(startIndex).setMaxResults g/6>>p`J
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(pageSize).list(); z8\z`#g!
PaginationSupport ps = '&hk?
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new PaginationSupport(items, totalCount, pageSize, Sr?2~R0&
*Z,?VEO
startIndex); ev;R; 0<
return ps; (^).$g5Hg
} m3i+b
}, true);
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} Q9h;`G
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public List findAllByCriteria(final (W4H?u@X0
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DetachedCriteria detachedCriteria){ Q,m1mIf
return(List) getHibernateTemplate 9(
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().execute(new HibernateCallback(){ dGY:?mf&
publicObject doInHibernate Y(3X5v?[
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(Session session)throws HibernateException { &@h(6
Criteria criteria = ~dc~<hK
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detachedCriteria.getExecutableCriteria(session); R+y 9JE
return criteria.list(); )D"E]
} <UC_QPA\
}, true); B
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} 6wY6*R
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public int getCountByCriteria(final KJ;;825?
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DetachedCriteria detachedCriteria){ +<o}@hefY2
Integer count = (Integer) >q7/zl
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getHibernateTemplate().execute(new HibernateCallback(){ \hr2#!
publicObject doInHibernate wYAi-gdOi
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(Session session)throws HibernateException { BL^\"Xh$|
Criteria criteria = |qFCzK9tD/
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detachedCriteria.getExecutableCriteria(session); 1ms(03dp
return oW
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criteria.setProjection(Projections.rowCount yrVk$k#6}
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()).uniqueResult(); U8gf_R'
} A5[iFT>
}, true); M\rZr3
return count.intValue(); rCp'O\@S
} ]5Mq^@mD'
} F2:nL`]b[
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用户在web层构造查询条件detachedCriteria,和可选的 ]oIP;J:&
_(%;O:i
startIndex,调用业务bean的相应findByCriteria方法,返回一个 me@xl}
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PaginationSupport的实例ps。 *'ffMnSZ
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ps.getItems()得到已分页好的结果集 k ^(RSu<
ps.getIndexes()得到分页索引的数组 d$T856
ps.getTotalCount()得到总结果数 3F ]30
ps.getStartIndex()当前分页索引 2{;~Bgd
ps.getNextIndex()下一页索引 s5cY>
ps.getPreviousIndex()上一页索引 %;MM+xVVX
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P4{!/&/
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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 sRKoM
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一下代码重构了。 I:Q3r"1
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我把原本我的做法也提供出来供大家讨论吧: ~lH_d[
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首先,为了实现分页查询,我封装了一个Page类: /JbO $A
java代码: '?)<e^
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/*Created on 2005-4-14*/ `m+o^!SGe
package org.flyware.util.page; #L`'<ge'g*
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/** ZXH{9hxd
* @author Joa yp
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* n>k 1D
*/ `),ACkU>U
publicclass Page { _oAWj]~rO
&Fy})/F3v
/** imply if the page has previous page */ E@[ZwTnJ
privateboolean hasPrePage; wGhy"1g#
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/** imply if the page has next page */ ag{cm'.
privateboolean hasNextPage; h}&1
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bSgdVP-
/** the number of every page */ $*q^7ME
privateint everyPage; S\<nCkE^
UR<a7j"@2
/** the total page number */ AXT(D@sI=
privateint totalPage; /w
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/** the number of current page */ hywy(b3
privateint currentPage; )PCh;P0C
}=$>w@mJ
/** the begin index of the records by the current i)=dp!Bx^
%2,'x
query */ NnTAKd8
privateint beginIndex; <:ptNGR
R?5v//[
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/** The default constructor */ g(QT"O!dY
public Page(){ ":W$$w<
x.kIzI5
} PQvpJFpb~h
SbK6o:[
/** construct the page by everyPage JxmFUheLt
* @param everyPage "(+p1
* */ IrMxdF~c
public Page(int everyPage){ S pIdw0
this.everyPage = everyPage; iTcq=
} [Ufx=BPx3
}UX0 eI4
/** The whole constructor */ kO/]mNLG
public Page(boolean hasPrePage, boolean hasNextPage, EK2mJCC|
lcfX(~/m^
y#v<V1b]
int everyPage, int totalPage, e+O502]
int currentPage, int beginIndex){ :R1F\FT*
this.hasPrePage = hasPrePage; J. $U_k
this.hasNextPage = hasNextPage; nxhn|v
this.everyPage = everyPage; ^?R8>97_?
this.totalPage = totalPage; 8fWk C<f}
this.currentPage = currentPage; \V%l.P4>e
this.beginIndex = beginIndex; m<I>NYfE
} <_3OiU=w
[ XBVES8
/** ]US
* @return pE381Cw
* Returns the beginIndex. ?.Lq`~T`
*/ }s@vN8C
publicint getBeginIndex(){ A;Av0@w
return beginIndex; #u/5
nm
} s`I]>e
<~}NxY\5
/** R
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* @param beginIndex H6Q!~o\"H
* The beginIndex to set. K+3+?oYKH
*/ K9QC$b9(
publicvoid setBeginIndex(int beginIndex){ WPDi)UX
this.beginIndex = beginIndex; ;D|g5$OE&
} EYSBC",
LO@o`JF
/** bzyy;`;6Q~
* @return 6<Txkk
* Returns the currentPage. a/TeBx#yG
*/ 8iUYZF
publicint getCurrentPage(){ '#NDR:J"
return currentPage; t~M0_TnXlP
} 0S#T}ITm4Z
*('Vyd!n
/** nO
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* @param currentPage SQ-CdpT<
* The currentPage to set. :0'vz M
*/ a St:G*a"
publicvoid setCurrentPage(int currentPage){ %*];XpAE
this.currentPage = currentPage; {y`n_
} {4>N2mP{M
a[ yyEgm2
/** e/R$Sfj]
* @return UTVqoCHA
* Returns the everyPage. ]N{jF$
*/ :&J1#% t
publicint getEveryPage(){ ,'%*z
return everyPage; #'8'5b
} O"9Or3w
|h-e+Wh1
/** wxE'h~+
* @param everyPage h~5gHx/a
* The everyPage to set. $fAZ^
*/ ,SH^L|I
publicvoid setEveryPage(int everyPage){ -=GmI1:=$4
this.everyPage = everyPage; @umn[J#*
} 4P?R "Lk
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/** ( "wmc"qH
* @return ~F[JupU
* Returns the hasNextPage. hVW1l&s
*/ t#2szr+
publicboolean getHasNextPage(){ \kP1 Jr
return hasNextPage; G;AJBs>Y}
} ;N^4R$Q.
o?5;l`.L}
/** g9AA)Ykp
* @param hasNextPage B4{F)Zb
* The hasNextPage to set. 9`cj9zz7
*/
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publicvoid setHasNextPage(boolean hasNextPage){ 6ag0c&k
this.hasNextPage = hasNextPage; ~\u~>mtchu
} rO]2we/B,4
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/** 8qwPk4
* @return ]%Lk#BA@A
* Returns the hasPrePage. KqvM5$3
*/ "ZP)[ [Rd
publicboolean getHasPrePage(){ kiu#THF
return hasPrePage; ^zKP5nzL
} XGAR8=tic
uQ3W =
/** VEx
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* @param hasPrePage 8Ud.}<
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* The hasPrePage to set. Q1RUmIe_&
*/ KouIzWf.
publicvoid setHasPrePage(boolean hasPrePage){ H](TSt<Q"
this.hasPrePage = hasPrePage; s]Z++Lh<{
} V(M7d>N5G
&IP`j~b
/** Dv}VmC""
* @return Returns the totalPage. l} W">
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* $fwj8S7$
*/ }[: i!t.m
publicint getTotalPage(){ ggUw4w/e
return totalPage; :.crES7<[X
} c>+hY5?C
+T HBPEq
/** +kx#"L:
* @param totalPage pt%Y1<9Eh?
* The totalPage to set. o"g<Vz
*/ 6c*QBzNL
publicvoid setTotalPage(int totalPage){ N3ccn
this.totalPage = totalPage; y6&o+;I$[
} gM&4Ur
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} s[%@3bY!7
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m0 ]Lc{
t8uaNvUM}e
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 S+u@
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个PageUtil,负责对Page对象进行构造: i([|@Y=
java代码: &X)^G#
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.2SD)<}(9
/*Created on 2005-4-14*/ aPHNX)
package org.flyware.util.page; sM@1Qyv&0
te+r.(p
import org.apache.commons.logging.Log; gP?.io9Oi
import org.apache.commons.logging.LogFactory; " (yw(/
p5#UH
/** E2Ec`o
* @author Joa v dPb-z4
* s}?QA cC
*/ 8[x{]l[
publicclass PageUtil { J'*`K>wV
v4r%'bA
privatestaticfinal Log logger = LogFactory.getLog ms#|Yl1/|
I]Vkaf I>(
(PageUtil.class); a>#]d
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u
/** u(g9-O
* Use the origin page to create a new page EO"G(v
* @param page (#rhD}
* @param totalRecords U?j[
8z
* @return >uwd3XW5
*/ 4)d"}j
publicstatic Page createPage(Page page, int +krDmU9(
[ N0"mE<
totalRecords){ IhXP~C6
return createPage(page.getEveryPage(), )odz/\9n3c
|\N))K-2D
page.getCurrentPage(), totalRecords); nQd~i0`vB
} LuWY}ste
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/** RH"EO4
* the basic page utils not including exception U\6Ee-1#_
h-5] nL3
handler `A$zLqz)Vm
* @param everyPage T<U_Iq
* @param currentPage 34t[]v|LD
* @param totalRecords h 2C9p2.
* @return page >Slu?{l'
*/ YT<(2u#Ng
publicstatic Page createPage(int everyPage, int E]ZIm
7%i6zP/a
currentPage, int totalRecords){ s:^Xtox/
everyPage = getEveryPage(everyPage); N.-*ig.YR7
currentPage = getCurrentPage(currentPage); Zi.w+V
int beginIndex = getBeginIndex(everyPage, [~k!wipK
BHDd^bd
currentPage); CFG(4IMx
int totalPage = getTotalPage(everyPage, tTPjCl
0|FQIhVuY
totalRecords); ._(5; PB"
boolean hasNextPage = hasNextPage(currentPage, r-5xo.J'
_Q}vPSJviC
totalPage); sLW e \o
boolean hasPrePage = hasPrePage(currentPage); _q`f5*Z[
k];fQ7}m<0
returnnew Page(hasPrePage, hasNextPage, (ljoD[kZ
everyPage, totalPage, e4-7&8N+
currentPage, @"0n8y
D"X`qF6U7
beginIndex); e.]k4K
} :YNXS;>)!
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privatestaticint getEveryPage(int everyPage){ .p-T >
return everyPage == 0 ? 10 : everyPage; [W=6NAd
} cTLW}4m%g
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privatestaticint getCurrentPage(int currentPage){ DpQ:U 5j
return currentPage == 0 ? 1 : currentPage; [wcp2g3Px
} w s7LDY&(
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privatestaticint getBeginIndex(int everyPage, int RNb" O{3
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currentPage){ IvM>z03
return(currentPage - 1) * everyPage; !Z%pdqo`.
} 47^7S=
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privatestaticint getTotalPage(int everyPage, int Pi=B\=gs
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totalRecords){ @vvGhJ1m`
int totalPage = 0; <Y ^)/ s
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if(totalRecords % everyPage == 0) o<!tNOH
totalPage = totalRecords / everyPage; #LfoG?k1K
else I->4Q&3
totalPage = totalRecords / everyPage + 1 ; N683!wNX
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return totalPage; ^qV6khg
} Hq "l`
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privatestaticboolean hasPrePage(int currentPage){ 9l}G{u9a
return currentPage == 1 ? false : true; nrCr9#
} YbuS[l8
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privatestaticboolean hasNextPage(int currentPage, &U
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int totalPage){ R<e ~Cb-
return currentPage == totalPage || totalPage == pSS8 %r%S'
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0 ? false : true; n<Z1i)
} {'[S.r`
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} w7yz4_:x^
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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
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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 h|[oQ8)
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做法如下: d 8M8O3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]McDN[h:
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的信息,和一个结果集List: zC_@wMWB
java代码: _:VIlg
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/*Created on 2005-6-13*/ #\gx.2W7
package com.adt.bo; t? [8k&Z
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import java.util.List; H]VoXJ\*
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import org.flyware.util.page.Page; +cC$4t0$^A
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/** rjL4t^rT
* @author Joa |M(0CYO
*/ 0v'!(&m
publicclass Result { wZKEUJpQ
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private Page page; o/mGd~
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private List content; \Qei}5P,
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/** poVtg}n
* The default constructor ljJR7<
*/ JId|LHf*P
public Result(){ ]rc=oP;
super();
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} 8d8GYTl b)
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/** U$ 22 r b
* The constructor using fields Yo[Pu< zR
* R6-Z]Hu
* @param page 3Tz~DdB
* @param content <,I]=+A
*/ AMc`qh
public Result(Page page, List content){ D~7L~Q]xI
this.page = page; +/DT#}JE
this.content = content; < <]uniZ\
} +l(lpp>,
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/** ~=Q Tv8
* @return Returns the content. _q3|Ddm2LN
*/ SB=%(]S
publicList getContent(){ *#Hw6N0#
return content; Pm!/#PtX
} hO0g3^
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/** QT7PCHP
* @return Returns the page. ioJr2wq6
*/ )@a_|q@V
public Page getPage(){ x0$# 8
return page; (?lKedA>2
} W^N|+$g>H
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/** {q|Om?@
* @param content J:oAzBFpA
* The content to set. j|2s./!Qg
*/ M*7:-Tb]C
public void setContent(List content){ HAc1w]{(
this.content = content; Bd>a"3fA
} p5JRG2zt
od RtJ[
/** qotWWe#
* @param page $W0O
* The page to set. Ym$=^f]-
*/ y$U(oIU>
publicvoid setPage(Page page){ `F4gal^ ^
this.page = page; n5;>e&
} 5Za%EaW%G
} g~]?6;uu
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2. 编写业务逻辑接口,并实现它(UserManager, [ %6(1$Ih
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UserManagerImpl) $#/f+kble
java代码: ^s_7-p])(
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/*Created on 2005-7-15*/ #MAXH7[
package com.adt.service; 5Sz}gP('
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import net.sf.hibernate.HibernateException; gt)wk93d>
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import org.flyware.util.page.Page;
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import com.adt.bo.Result; M}x]\#MMY
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/** Am"e%|:
* @author Joa <db>~@;X!
*/ `PS>"-AY2
publicinterface UserManager { w'7=CzfYn
5Sx.'o$
public Result listUser(Page page)throws l'
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tzrvIVD
HibernateException; oUx%ra{
}) Zcw1g
} 'mO>hD`V
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java代码: U6F1QLSLz
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/*Created on 2005-7-15*/ VCQo3k5
{
package com.adt.service.impl; _(F8}s
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import java.util.List; IQeiT[TF
y7|
3]>Z
import net.sf.hibernate.HibernateException;
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import org.flyware.util.page.Page; ,)ZI&BL5
import org.flyware.util.page.PageUtil; r1/9BTPKdJ
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import com.adt.bo.Result; hO; XJyv
import com.adt.dao.UserDAO; &gsBbQ+qA
import com.adt.exception.ObjectNotFoundException; p> g[: ~
import com.adt.service.UserManager; v W4n>h}]
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/** %uDH_J|^
* @author Joa "NtY[sT{V
*/ R*DQLBWc
publicclass UserManagerImpl implements UserManager { 7>
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private UserDAO userDAO; M< /
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/** .zv BV_I
* @param userDAO The userDAO to set. 8p_6RvG
*/ 9J$-E4G.M
publicvoid setUserDAO(UserDAO userDAO){ zD;k|"e
this.userDAO = userDAO; uR6 `@F
} lRR A2Kql
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/* (non-Javadoc) Y`rli
* @see com.adt.service.UserManager#listUser nt8&Mf
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(org.flyware.util.page.Page) i!EAs`$o`
*/ {r'+icvLX
public Result listUser(Page page)throws X}H?*'-
U=PTn(2
HibernateException, ObjectNotFoundException { ^@^K
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int totalRecords = userDAO.getUserCount(); `T{'ufI4B
if(totalRecords == 0) hlmeT9v{
throw new ObjectNotFoundException @MO/LvD
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("userNotExist"); iFnD`l6)
page = PageUtil.createPage(page, totalRecords); .FG%QF F~
List users = userDAO.getUserByPage(page);
wSi$.C2
returnnew Result(page, users); Q89fXi0Ivb
} ?AK`M #M
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} [0vqm:P
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 a|#TnSk
9{
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询,接下来编写UserDAO的代码: N&