Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 CTZ8Da^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 JAem0jPC8
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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 #;2n;.a
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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 #ZrHsfP
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分页支持类: 7%|~>
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java代码: ?q{,R"
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package com.javaeye.common.util; A#J`;5!Sc
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import java.util.List; 9\BT0kx
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publicclass PaginationSupport { S]Mw#O|
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publicfinalstaticint PAGESIZE = 30; 'R'*kxf
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privateint pageSize = PAGESIZE; eoG$.M"
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privateList items; jN;@=COi
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privateint totalCount; OuID%p"O
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privateint[] indexes = newint[0]; $Y/9SV,
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privateint startIndex = 0; ;RC{<wBTx
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public PaginationSupport(List items, int 7WkB>cn
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totalCount){ .*Ct bGw
setPageSize(PAGESIZE); K}buH\yco
setTotalCount(totalCount); %,}A@H,
setItems(items); 9=8iy
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setStartIndex(0); ~obqG!2m
} ORHp$Un~)
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public PaginationSupport(List items, int Q
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totalCount, int startIndex){ `>f6)C-
setPageSize(PAGESIZE); mS$j?>m
setTotalCount(totalCount); pN:Kdi
setItems(items); dJeNbVd
setStartIndex(startIndex); c[wla<dO*
} -Ta9 pxZk
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public PaginationSupport(List items, int AN8`7F1
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totalCount, int pageSize, int startIndex){ |:q=T
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setPageSize(pageSize); :dl]h&C^
setTotalCount(totalCount); B(LWdap~
setItems(items); *4Thd:7 `
setStartIndex(startIndex); J%v=yBC2
} eL10Q(;P`
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publicList getItems(){ @5=oeOg36
return items; 2&:f&"
} u]<,,
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publicvoid setItems(List items){ Q]Y*K
this.items = items; n7B7 m,@1
} #%a;"w
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publicint getPageSize(){ H*RC@O_hv
return pageSize; -BrMp%C
} b#uL?f
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publicvoid setPageSize(int pageSize){ FcR=v0),
this.pageSize = pageSize; Ygm`ZA y
} 3m]4=
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publicint getTotalCount(){ jqWu
return totalCount; wKtl+}}
} aE`c%T):`
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publicvoid setTotalCount(int totalCount){ c(3~0Yr
if(totalCount > 0){ 4x{0iav
this.totalCount = totalCount; /7aBDc-v
int count = totalCount / rXmn7;B}g
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pageSize; ]{)a,c NG
if(totalCount % pageSize > 0) Eza`Z`
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count++; $*^kY;
indexes = newint[count]; ^nT/i
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for(int i = 0; i < count; i++){ d?s<2RkPT
indexes = pageSize * oz,np@f)J
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} }\z.)B4,
}else{ =}lh_
this.totalCount = 0; R?GDJ3
} Pj#<K%Bz
} v0
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publicint[] getIndexes(){ :Ux?,
return indexes; @GBxL*e
} =!kk|_0%E
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publicvoid setIndexes(int[] indexes){ ) brVduB
this.indexes = indexes; LIS)(X<]?
} n(b(yXYm]
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publicint getStartIndex(){ 8qY79)vD4E
return startIndex; `Bo*{}E
} Of-Rx/
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publicvoid setStartIndex(int startIndex){ `e(c^ z#
if(totalCount <= 0) C\3y {s
this.startIndex = 0; /,89p&h
elseif(startIndex >= totalCount) %@wJ`F2a_
this.startIndex = indexes h XfQ)$J
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[indexes.length - 1]; aK&b{d
elseif(startIndex < 0) W0y '5`
this.startIndex = 0; CUO+9X-<8
else{ G,$PV
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this.startIndex = indexes M3J#'%$
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[startIndex / pageSize]; :H7D~ n
} 0@yXi
} )'Oh`$M
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publicint getNextIndex(){ Da&vb
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int nextIndex = getStartIndex() + +1Vjw'P
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pageSize; `k=bL"T>\
if(nextIndex >= totalCount) >NqYyW,%
return getStartIndex(); 3 j!3E
else J1/?JfF
return nextIndex; l/BLUl~z
} fXXr+Mor
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publicint getPreviousIndex(){ 3b*cU}go
int previousIndex = getStartIndex() - \X<bH&x:z
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pageSize; *7*lE"$p
if(previousIndex < 0) *n;!G8\
return0; QBtnx[
else R#xCkl -
return previousIndex; x N=i]~
} zw+B9PYqX
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} H]Cy=Zi"
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抽象业务类 cYFiJJLG]
java代码: 2GFLnz
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/** Ae
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* Created on 2005-7-12 9w"h
*/
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package com.javaeye.common.business; W;_nK4$%'
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import java.io.Serializable; el2bd
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import java.util.List; eL^.,H0
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import org.hibernate.Criteria; UjaK&K+M?
import org.hibernate.HibernateException; pcau}5 .
import org.hibernate.Session; A~Y^VEn
import org.hibernate.criterion.DetachedCriteria; ZPiq-q
import org.hibernate.criterion.Projections; ] x\-$~E
import 1=#q5dZ]
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org.springframework.orm.hibernate3.HibernateCallback; 3mYiQ2
import ^
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org.springframework.orm.hibernate3.support.HibernateDaoS |o,8V p
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upport; A6GE,FhsG
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import com.javaeye.common.util.PaginationSupport; Wi[ ~fI8^!
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public abstract class AbstractManager extends CF+_/s#j^
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HibernateDaoSupport { M>&%(4K
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privateboolean cacheQueries = false; \zieyE
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privateString queryCacheRegion; )jkXSTZ
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publicvoid setCacheQueries(boolean 4Fp0ZVT
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cacheQueries){ ?"zY"*>4
this.cacheQueries = cacheQueries; 0GB:GBhZ
} xZ|Y?R5m
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publicvoid setQueryCacheRegion(String ~n[xtWO0
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queryCacheRegion){ 5WC+guK7
this.queryCacheRegion = 8'<-:KG
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queryCacheRegion; vk*=4}:
} ?_"+^R z
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publicvoid save(finalObject entity){ XK|R8rhg8`
getHibernateTemplate().save(entity); c6nflk.l
} 2>86oP&
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publicvoid persist(finalObject entity){ ]l'Y'z,}
getHibernateTemplate().save(entity); [%9noB
} U+)xu>I
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publicvoid update(finalObject entity){ jV?
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getHibernateTemplate().update(entity); TUHi5K
} q4}PM[K?=\
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publicvoid delete(finalObject entity){ L]d-hs
getHibernateTemplate().delete(entity); t5'V6nv
} Z^]|o<.<I
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publicObject load(finalClass entity, TF 'U
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finalSerializable id){ n|b5? 3
return getHibernateTemplate().load 87:!C5e}
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(entity, id); ?t+5s]
} p/U+0f
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publicObject get(finalClass entity, wjh=Q
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finalSerializable id){ L0&RvI#
return getHibernateTemplate().get AJSx%?h:6
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(entity, id); ~=KJzOS,S
} MXzVgy
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publicList findAll(finalClass entity){ #]#sGmW/L
return getHibernateTemplate().find("from RjWqGr;bO
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" + entity.getName()); Nnk@h
} #
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publicList findByNamedQuery(finalString UK1_0tp]x
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namedQuery){ jL^](J>
return getHibernateTemplate Q>R>R*1.j
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().findByNamedQuery(namedQuery); "Ae@lINn[y
} K
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publicList findByNamedQuery(finalString query, CBDG./
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finalObject parameter){ zCOgBT~p
return getHibernateTemplate OKi\zS
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().findByNamedQuery(query, parameter); z81esXl
} &q`q4g&7
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publicList findByNamedQuery(finalString query, ?x+Z)`w_
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finalObject[] parameters){ K]U;?h&CZc
return getHibernateTemplate xS7$%w['
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().findByNamedQuery(query, parameters); eL4NB$Fb
} 25NTIzI@@
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publicList find(finalString query){ ]$p{I)d&
return getHibernateTemplate().find ?KITC;\\
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(query); -tnQCwq#
} #/NS&_Ge0s
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publicList find(finalString query, finalObject rJa$9B*^
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parameter){ n39t}`WIl
return getHibernateTemplate().find %lX%8Z$v
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(query, parameter); >6oOZbUY0
} `fNG$ODL
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public PaginationSupport findPageByCriteria Ne$"g[uFU
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(final DetachedCriteria detachedCriteria){ lpRR&
return findPageByCriteria +525{Tj
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); rCS#{x
} =?h~.lo
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public PaginationSupport findPageByCriteria \m=?xb8
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(final DetachedCriteria detachedCriteria, finalint bln/1iS
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startIndex){ A:y.s;<L0
return findPageByCriteria v+e|o:o#
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(detachedCriteria, PaginationSupport.PAGESIZE, _U{([M>;
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startIndex); ]I/Vb s
} 'a^{=+
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public PaginationSupport findPageByCriteria q!f1~ aG
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(final DetachedCriteria detachedCriteria, finalint Z+pom7A"E
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pageSize, 0t#g}
finalint startIndex){ $T<}y_nHl
return(PaginationSupport) VD4C::J
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getHibernateTemplate().execute(new HibernateCallback(){ 24Z]%+b*E
publicObject doInHibernate AM} brO
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(Session session)throws HibernateException { =2y8CgLj
Criteria criteria = s7r9,8$
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detachedCriteria.getExecutableCriteria(session); n:U>Fj>q
int totalCount = wA`"\MWm
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((Integer) criteria.setProjection(Projections.rowCount .bf<<+'o
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()).uniqueResult()).intValue(); }.)s%4p8
criteria.setProjection 1\dn1Hh
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(null); Rq~t4sA:
List items = 9umGIQHnil
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criteria.setFirstResult(startIndex).setMaxResults ]WJfgN4
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(pageSize).list(); kqvow3u
PaginationSupport ps = ~un%4]U
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new PaginationSupport(items, totalCount, pageSize, -Uo?WXP]B'
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startIndex); nY `2uN~9
return ps; &jV_"_3n
} LT+3q%W.UC
}, true); =A[5=
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} A%Z)wz{
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public List findAllByCriteria(final F5gObIJtuY
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DetachedCriteria detachedCriteria){ <
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return(List) getHibernateTemplate TUp%FJXA|
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().execute(new HibernateCallback(){ K2'O]#
publicObject doInHibernate eIPG#A
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(Session session)throws HibernateException { oB c@]T5>
Criteria criteria = !)Ni dG
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detachedCriteria.getExecutableCriteria(session); F=@i6ERi
return criteria.list(); %4>x!{jwV
} ^E>CGGS4
}, true); 'bW5Fr>W
} ^!:"Q3
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public int getCountByCriteria(final 2%rLoL$Y2+
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DetachedCriteria detachedCriteria){ +p:Y=>bTj
Integer count = (Integer) {_ V0
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getHibernateTemplate().execute(new HibernateCallback(){ utO.WfWP
publicObject doInHibernate ;\b@)E}
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(Session session)throws HibernateException { Wr|G:(kw\!
Criteria criteria = @YL}km&Fw
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detachedCriteria.getExecutableCriteria(session); |w)5;uQ&\
return D$Kea
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criteria.setProjection(Projections.rowCount $Tl<V/
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()).uniqueResult(); k
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} Ky9W/dCR
}, true); Q</h-skLZ
return count.intValue(); H7IW"UkBR
} OeTu?d&N
} Y)p4]>lT+8
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用户在web层构造查询条件detachedCriteria,和可选的 pieT'mA
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 dtW0\^ .L
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PaginationSupport的实例ps。 z}APR@?`n8
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ps.getItems()得到已分页好的结果集 zl)&U=4l
ps.getIndexes()得到分页索引的数组 L+R>%d
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ps.getTotalCount()得到总结果数 w~-X>~ }
ps.getStartIndex()当前分页索引 {8m1dEC^@Q
ps.getNextIndex()下一页索引 &va*IR
ps.getPreviousIndex()上一页索引 zD_HyGf
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *gSO&O=
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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 *<dHqK`?C
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一下代码重构了。 +S0u=u65
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我把原本我的做法也提供出来供大家讨论吧: G+C}<S}
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首先,为了实现分页查询,我封装了一个Page类: )[
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java代码: |8'B/
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/*Created on 2005-4-14*/ |D(&w+(
package org.flyware.util.page; :B^mV{~
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/** T^NJ4L4#
* @author Joa qZ?{-Vw
* NxB+?
*/ _/Tlqzp
publicclass Page { gPp(e
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/** imply if the page has previous page */ #{~7G%GPY5
privateboolean hasPrePage; [yvt1:q
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/** imply if the page has next page */ a+'}XEhSC:
privateboolean hasNextPage; w Oj88J)
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/** the number of every page */ 6~3jn+K$1
privateint everyPage; e
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/** the total page number */ <H-tZDh5
privateint totalPage; ysl8LK
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/** the number of current page */ *F|i&2
privateint currentPage; e6o/q)9#
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/** the begin index of the records by the current ,Q+\h>I
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query */ h&q=I.3O|?
privateint beginIndex; q _19&;&
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/** The default constructor */ xSdN5RN
public Page(){ 98h :X %
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} {[my"n2
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/** construct the page by everyPage :ao^/&HZ
* @param everyPage 4bPqmEE
* */ 2 aew6~
public Page(int everyPage){ 3_C98ClE
this.everyPage = everyPage; Tw}@+-
} {qY3L8b
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/** The whole constructor */ W;q#ZD(;
public Page(boolean hasPrePage, boolean hasNextPage, YfV"_G.ad|
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int everyPage, int totalPage, !NILpimi
int currentPage, int beginIndex){ V[4(~,9
this.hasPrePage = hasPrePage; M\9at\$
this.hasNextPage = hasNextPage; (6e!09P&
this.everyPage = everyPage; ~K4k'
this.totalPage = totalPage; >F,$;y52
this.currentPage = currentPage; qw6EP C
this.beginIndex = beginIndex; XCW+ pUX
} u![4=w
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/** Lr K9F^c
* @return [[#xES21F
* Returns the beginIndex. JJ^iy*v
*/ }*xC:A%aS
publicint getBeginIndex(){ jB*9 !xrd,
return beginIndex; RmcYaj^=
} ,G916J*XA
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/** ]R97n|s_
* @param beginIndex ju8',ZC
* The beginIndex to set. QBg}2.
*/ 71K\.[ =-
publicvoid setBeginIndex(int beginIndex){ j:3A;r\
this.beginIndex = beginIndex; ~r(g|?}P
} XMjI}SPG
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/** ?q+8 /2
* @return 6^7)GCq [
* Returns the currentPage. wJ;9),fL
*/ FCsyKdM
publicint getCurrentPage(){ >qSO,$
return currentPage; g
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} dbf^A1HI
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/** 7H8GkuO
* @param currentPage GM34-GH+
* The currentPage to set. <) >gg!
*/ Ri^sQ<