Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 fpzTv3D=I
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 { u;ntDr
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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 X4o8
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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"2ye9a
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分页支持类: -j(/5.a
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java代码: h;B'#$_
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package com.javaeye.common.util; C|>#|5XaF
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import java.util.List; F:\y#U6"J
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publicclass PaginationSupport { _{A($/~c?
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publicfinalstaticint PAGESIZE = 30; Z(V4"x7F
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privateint pageSize = PAGESIZE; } wiq?dr
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privateList items; 2Aff3]-:Gd
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privateint totalCount; r[hfN2,#
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privateint[] indexes = newint[0]; }e82e
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privateint startIndex = 0; ;z&p(e
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public PaginationSupport(List items, int l
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totalCount){ K%Rx5 S
setPageSize(PAGESIZE); ' rXkTm1{
setTotalCount(totalCount); 0z,c6MjM+
setItems(items); $bN%x/
setStartIndex(0); )2R:P`U
} r*kk/$,2
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public PaginationSupport(List items, int 4YdmG.CU
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totalCount, int startIndex){ R^K<u#>K
setPageSize(PAGESIZE); aZmSCi:&'
setTotalCount(totalCount); 2Qn%p[#n
setItems(items); `B^?Za,xN
setStartIndex(startIndex); VD1*br^,
} tv?~LJYN
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public PaginationSupport(List items, int oW-luC+
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totalCount, int pageSize, int startIndex){ zRu}lJ1#W$
setPageSize(pageSize); b7=]"|c$@
setTotalCount(totalCount); !QYqRH~5
setItems(items); fIFB"toiPE
setStartIndex(startIndex); Rk"_4zJk
} (}}BZS&.
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publicList getItems(){ G66vzwO
return items; 6W~F
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} FzW(An&x2
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publicvoid setItems(List items){ }bHdU]$}
this.items = items; =_TCtH
} ;zs4>>^>
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publicint getPageSize(){ |JrG?:n
return pageSize; 7|H !( a'
} FCOSgEU
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publicvoid setPageSize(int pageSize){ 3:S
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this.pageSize = pageSize; V}3.K\7
} =7Nm=5@
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publicint getTotalCount(){ uI+h9j$vS
return totalCount; ][D<J0
} ZJd1Lx
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publicvoid setTotalCount(int totalCount){ M)Y`u
if(totalCount > 0){ Ib]{rmaP
this.totalCount = totalCount; rjfQ\W;}U
int count = totalCount / x@Q}sW92
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pageSize; fU$zG"a_
if(totalCount % pageSize > 0) xpUaFb
count++; -<qci3Ba}
indexes = newint[count]; U
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for(int i = 0; i < count; i++){ \u:xDS(
indexes = pageSize * \O@,v0?R
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i; \9<aCJxN
} mM>{^%2Q:
}else{ z[V|W
this.totalCount = 0; .LdLm991,Y
} kE/>Ys@w
} C S+6!F]
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publicint[] getIndexes(){ 4km=KOx[
return indexes; c7S<ex,
} F@&q4whaVD
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publicvoid setIndexes(int[] indexes){ ^-mz!{
this.indexes = indexes; =|=9\3po
} X8F _Mb*
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publicint getStartIndex(){ X,^J3Ek>O
return startIndex; v?5Xx{ym
} qH$G_R#)8B
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publicvoid setStartIndex(int startIndex){ q4Qm:|-
if(totalCount <= 0) )k=8.j4
this.startIndex = 0; [\eUCt F
elseif(startIndex >= totalCount) }kGJ)zh
this.startIndex = indexes ,Rz,[KI|
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[indexes.length - 1]; NhXTt!S6C
elseif(startIndex < 0) ME{i-E4
this.startIndex = 0; \2pJ ]
else{ USJ4qv+-
this.startIndex = indexes r(0I>|u
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[startIndex / pageSize]; ,)u}8ty3j
} ^o65sM
} wE;??'O'l
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publicint getNextIndex(){ kR9G;IZ8s
int nextIndex = getStartIndex() + 3]M
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pageSize; { SJ=|L6
if(nextIndex >= totalCount) f!eC|:D
return getStartIndex(); pNCk~OM
else !JJCG
return nextIndex; ey@y?X=
} 2j*\n|"}{
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publicint getPreviousIndex(){ i%D/@$\D6
int previousIndex = getStartIndex() - vUY?Eb[
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pageSize; bvk+i?{H
if(previousIndex < 0) TdG[b1xN
return0; u7<B*d:
else E&jngxlN
return previousIndex; C<eeAWP3v
} w[UPoG #Uh
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} .9S
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抽象业务类 LX!16a@SxA
java代码: -;_NdL@
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/** lKxv
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* Created on 2005-7-12 i=#r JK=
*/ u,*$n'l]
package com.javaeye.common.business; \/. Of]YQ
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import java.io.Serializable; m{I_E
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import java.util.List; 6^s]2mMfk
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import org.hibernate.Criteria; 8pg?g'A~}
import org.hibernate.HibernateException; Zj[Bm\8
import org.hibernate.Session; )|q,RAn
import org.hibernate.criterion.DetachedCriteria; ?,;|*A
import org.hibernate.criterion.Projections; +g@@|&B
import !D7[R'RgY
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org.springframework.orm.hibernate3.HibernateCallback; vFV->/u
import !c\s)&U7B
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org.springframework.orm.hibernate3.support.HibernateDaoS kS8srT
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upport; kS[k*bN0
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import com.javaeye.common.util.PaginationSupport; uZW
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public abstract class AbstractManager extends |bVNlL"xN
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HibernateDaoSupport { >OBuHqC
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privateboolean cacheQueries = false; I^qk` 5w
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privateString queryCacheRegion; o.Mb~8Yu
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publicvoid setCacheQueries(boolean -$.$6"]
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cacheQueries){ iShB^
this.cacheQueries = cacheQueries; =uYSZR
} 6jO*rseC
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publicvoid setQueryCacheRegion(String eWhv X9
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queryCacheRegion){ Z8}Zhe.
this.queryCacheRegion =
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queryCacheRegion; e-]k{_wm
} N?p9h{DG
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publicvoid save(finalObject entity){ Sr,ZM1J
getHibernateTemplate().save(entity); M+ ^]j
} EJNj.c-#
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publicvoid persist(finalObject entity){ ;KbnaUAS8
getHibernateTemplate().save(entity); w(k7nGU]
} X6N^<Z$
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publicvoid update(finalObject entity){ k(3s^B
getHibernateTemplate().update(entity); uY5f mM9
} aL-V 9y
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publicvoid delete(finalObject entity){ /ZvNgaH5M
getHibernateTemplate().delete(entity); hOO)0IrIM*
} ~g;(`g
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publicObject load(finalClass entity, Bb}JyT
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finalSerializable id){ a^)7&|$ E
return getHibernateTemplate().load Yc"G="XP;
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(entity, id); R
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} +G7A.d`V}
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publicObject get(finalClass entity, mucY+k1>g
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finalSerializable id){ }u5 Mexs
return getHibernateTemplate().get z ,P:i$
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(entity, id); [A
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} P=KOw;bs
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publicList findAll(finalClass entity){ l9qq;hhGP,
return getHibernateTemplate().find("from $*G]6s
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" + entity.getName()); .Uh-Wi[
} w44{~[0d4
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publicList findByNamedQuery(finalString #v89`$#`2
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namedQuery){ aS'G&(_
return getHibernateTemplate DJr 8<u
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().findByNamedQuery(namedQuery); 1k-^LdDj
} nm*1JA.:
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publicList findByNamedQuery(finalString query, 2a (w7/W:
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finalObject parameter){ f|m.v
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return getHibernateTemplate Lyt6DvAp"
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().findByNamedQuery(query, parameter); \%mR*J+
} 8W[QV
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publicList findByNamedQuery(finalString query, -x:Wp*,
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finalObject[] parameters){ (|(Y;%>-v
return getHibernateTemplate `5O<U~'d
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().findByNamedQuery(query, parameters); !}l)okQH<#
} ",#rI+ el
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publicList find(finalString query){ BXZ( %tnY
return getHibernateTemplate().find !D7\$
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(query); qVZ=:D{
} sN5x\9U
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publicList find(finalString query, finalObject 3P^eD:)
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parameter){ u32wS$*8
return getHibernateTemplate().find qAivsYN*
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(query, parameter); O4]Ss}ol
} &|n*&@fF
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public PaginationSupport findPageByCriteria A!Xn^U*p
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(final DetachedCriteria detachedCriteria){ hy
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return findPageByCriteria 4JU#3
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); s
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} K*7*`6iU
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public PaginationSupport findPageByCriteria ,(OA5%A9zK
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(final DetachedCriteria detachedCriteria, finalint WuSRA<{P
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startIndex){ }{=%j~V;&
return findPageByCriteria Vn=J$Uv0
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(detachedCriteria, PaginationSupport.PAGESIZE, XL EA|#
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startIndex); (0Hhn2JA
} _L%/NXu,
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public PaginationSupport findPageByCriteria P:ys--$"
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(final DetachedCriteria detachedCriteria, finalint o"7,CQye
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pageSize, IW6;ZDP
finalint startIndex){ bnB}VRal
return(PaginationSupport) _$MoMg{uJH
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getHibernateTemplate().execute(new HibernateCallback(){ 0kmVP~K
publicObject doInHibernate &|/C*2A
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(Session session)throws HibernateException { X k<X:,T
Criteria criteria = <0JW[m
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detachedCriteria.getExecutableCriteria(session); <:q]t6]$
int totalCount = JOenVepQ,
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((Integer) criteria.setProjection(Projections.rowCount
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()).uniqueResult()).intValue(); Z|' tw^0e5
criteria.setProjection e0v&wSi
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(null); F'pD_d9]e
List items = _$i9Tk
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criteria.setFirstResult(startIndex).setMaxResults R0oP##]
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(pageSize).list(); )oAK)e
PaginationSupport ps = pf] sL/g
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new PaginationSupport(items, totalCount, pageSize, m"H9C-Y
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startIndex); h=d&@k\g
return ps; 4;w_o9o
} L_ 8C=MS
}, true); 5#QB&A>
} gmJJ(}HVz
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public List findAllByCriteria(final `S$BBF;
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DetachedCriteria detachedCriteria){ 'hU&$lgMF
return(List) getHibernateTemplate a l#yc
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().execute(new HibernateCallback(){ CFRo>G
publicObject doInHibernate 9)l[$X
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(Session session)throws HibernateException { <aL$d7
Criteria criteria = K
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detachedCriteria.getExecutableCriteria(session); Ji%T|KR_
return criteria.list(); &qrH
} "z@qG]#5
}, true); (iBBdB
} ]9;WM.
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public int getCountByCriteria(final //V?rs
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DetachedCriteria detachedCriteria){ WlWBYnphZs
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate B1*%pjy
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(Session session)throws HibernateException { )Cu"M#`
Criteria criteria = 0o`0Td
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detachedCriteria.getExecutableCriteria(session); E$smr\
return LB 2
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criteria.setProjection(Projections.rowCount ]J_Dn\
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()).uniqueResult(); <
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} l EQn2+
}, true); @}aK\
return count.intValue(); $n(@hT>?
} Wc-P= J*m
} mP3:Fc_G
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用户在web层构造查询条件detachedCriteria,和可选的 j_p.KF'[?
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nCXIWLw
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PaginationSupport的实例ps。 9Z7o?S";
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ps.getItems()得到已分页好的结果集 [x-Z)Q.5
ps.getIndexes()得到分页索引的数组 -$[=AqJXp;
ps.getTotalCount()得到总结果数 "+saI@G
ps.getStartIndex()当前分页索引 .o.@cLdU
ps.getNextIndex()下一页索引 jf .ikxm
ps.getPreviousIndex()上一页索引 cZ^$!0
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 RQ}x7</{
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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 Qzb8*;4?FF
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一下代码重构了。 $ZwsTV]x
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我把原本我的做法也提供出来供大家讨论吧: /Hx%gKU
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首先,为了实现分页查询,我封装了一个Page类: h/eKVRGs"
java代码: AB}Qd\
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/*Created on 2005-4-14*/ Njz,y}\
package org.flyware.util.page; Oh<Z0M)
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/** _qJ[~'m<^C
* @author Joa '2:Ily,S@
* }6m5MH$7q
*/ >nvreis
publicclass Page { $0iz;!w
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/** imply if the page has previous page */ LNk
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privateboolean hasPrePage; 1pO ;aG1O
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/** imply if the page has next page */ 6t/})Xv
privateboolean hasNextPage; E(]yjZ/
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/** the number of every page */ ~g>15b3
privateint everyPage; Tff7SEP
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/** the total page number */ YM+}Mmu
privateint totalPage; YN"102CK
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/** the number of current page */ -aKL
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privateint currentPage; G}D?+MWY
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/** the begin index of the records by the current hiU_r="*ox
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query */ J6NQ5S\
privateint beginIndex; >i@gR
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/** The default constructor */ l_^>spF
public Page(){ Z0`?
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} ;@v7AF6Hq
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/** construct the page by everyPage ]p+t>'s
* @param everyPage W+Gu\=s%O
* */ G9Azd^3
public Page(int everyPage){ 8*6J\FE<p
this.everyPage = everyPage; $`_(%tl
} VJHHC.Kz
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/** The whole constructor */ !i}G>*XH,
public Page(boolean hasPrePage, boolean hasNextPage, t6-c{ZX>A
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int everyPage, int totalPage, [>Q{70 c[
int currentPage, int beginIndex){ 9OT2yCT
this.hasPrePage = hasPrePage; &\Cvrxa
this.hasNextPage = hasNextPage; EB@!?=0x
this.everyPage = everyPage; a-i#?hld
this.totalPage = totalPage; Z4hP
this.currentPage = currentPage; HzH_5kVW
this.beginIndex = beginIndex; W,AI E6F
} zL)S,
{
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/** +u25>pX
* @return Dtd
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* Returns the beginIndex. }})4S;j
*/ 8 _`Lx_R
publicint getBeginIndex(){ _eO+O=j_x
return beginIndex; Of([z!'Gc
} Zd~s5
l*% voKZG
/** 4Z]^v4vb
* @param beginIndex '*-X3p
* The beginIndex to set. b;!ilBc
*/ S$muV9z2=
publicvoid setBeginIndex(int beginIndex){ mpr["C"l
this.beginIndex = beginIndex; :GL|:
} -!;vX
@
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/** b2p<!?
* @return DB?_E{y]
* Returns the currentPage. <JZ=K5
*/ ?7a<V+V:
publicint getCurrentPage(){ C .YtjLQP$
return currentPage; rw+0<r3|K
} nR"k%$
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/** QfwGf,0p
* @param currentPage c%uhQ62
* The currentPage to set. r=@h}TKv{I
*/ bIWcL$}4Q
publicvoid setCurrentPage(int currentPage){ 7Dm^49H
this.currentPage = currentPage; $8_*LR$
} hc0VS3 k)
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/** Txoc
* @return r% mN]?u
* Returns the everyPage. TTy1a:V
*/ z$;%SYI
publicint getEveryPage(){ lD C74g
return everyPage; w2$HP/90j
} g`J? 2
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/** JZP2NB_xt
* @param everyPage -*yj[?6
* The everyPage to set. Iun!rv
*/ ap;UxWqx
publicvoid setEveryPage(int everyPage){ +[~\\X
this.everyPage = everyPage; 8^< -;
} u c7Y8iO
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/** \DGm[/P
* @return vv%Di.V
* Returns the hasNextPage. deu+ i
*/ =4Ex'
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publicboolean getHasNextPage(){ :B=`^>RK
return hasNextPage; nMVThN*Ig
} DB>>U>H-
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/** *?KQ\ Y
* @param hasNextPage R9=,T0Y
p
* The hasNextPage to set. ]]`+aF0
*/ r-Dcc;+=Q
publicvoid setHasNextPage(boolean hasNextPage){ !uHI5k,f
this.hasNextPage = hasNextPage; #UXmTrZ.
} CT"0"~~
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/** %
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* @return [;I.aT}R!;
* Returns the hasPrePage. ~r=TVHjqi
*/ |:
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publicboolean getHasPrePage(){ "Ny_RF
return hasPrePage; a`|/*{
} 1 !\pwd@{
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/** G.oaDGy
* @param hasPrePage E,C<ox4e
* The hasPrePage to set. fylaH(LER
*/ \t!+]v8f8
publicvoid setHasPrePage(boolean hasPrePage){ 3:=XU9p)x
this.hasPrePage = hasPrePage; ?58pkg J
} CQtd%'rt6
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/** Wa[~)A
* @return Returns the totalPage. SXod r}
* z,]fR
*/ A#jiCIc
publicint getTotalPage(){ $B$=,^)3
return totalPage; XUSfOf(
} <F=j6U7
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/** ^k-H$]
* @param totalPage yyA/x,
* The totalPage to set. 5h20\b?=$
*/ /n"A%6S
publicvoid setTotalPage(int totalPage){ .vT'hu
this.totalPage = totalPage; ?94da4p
} 9Z+@i:_}
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} Js=|r;'
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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 0p[$8SCJ
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个PageUtil,负责对Page对象进行构造: \XB71DUF
java代码: ]AHi$Xx
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/*Created on 2005-4-14*/ }]n&" =Zk-
package org.flyware.util.page; {{<o1{_H
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import org.apache.commons.logging.Log; <MfB;M
import org.apache.commons.logging.LogFactory; z5{I3 Y!1
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/** pH"LZ7)DI0
* @author Joa qKSM*k~
* r!x^P=f,MJ
*/ @nZFw.
publicclass PageUtil { cF/FretoO
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privatestaticfinal Log logger = LogFactory.getLog 'Y&yt"cs
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(PageUtil.class); awC&xVf
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/** PGw"\-F
* Use the origin page to create a new page WV&BZ:H
* @param page H-rf?R2
* @param totalRecords *2>%>qu
* @return s]2k@3|e
*/ uvmNQg
publicstatic Page createPage(Page page, int iT|+<h
-)$)<k
totalRecords){ M>vM@j
return createPage(page.getEveryPage(), NGxii$F
h 1Q7(8=Eg
page.getCurrentPage(), totalRecords); 9#3+k/A
} ^SjGNg^ 7D
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/** z2dM*NMK
* the basic page utils not including exception pCC0:
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handler cAiIbh>c
* @param everyPage bMv9f
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* @param currentPage n"MFC
* @param totalRecords hyTi':
* @return page p jrA:;
*/ E|5gKp-wJ
publicstatic Page createPage(int everyPage, int VvltVYOZA
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currentPage, int totalRecords){ GUcuD^Fe
everyPage = getEveryPage(everyPage); |Y])|`_'G
currentPage = getCurrentPage(currentPage); 2cmqtlW"
int beginIndex = getBeginIndex(everyPage, [&zP$i&
i"-#1vy=
currentPage); VK NCK
int totalPage = getTotalPage(everyPage, .:lzT"QXI
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totalRecords); ]&9f:5',
boolean hasNextPage = hasNextPage(currentPage, Z
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q,*IR*B:a
totalPage); v =u|D$
boolean hasPrePage = hasPrePage(currentPage); Mv9s
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returnnew Page(hasPrePage, hasNextPage, jn+0g:l
everyPage, totalPage, "`3H0il;<
currentPage, W"2\vo)
),~Ca'TU
beginIndex); z.jGVF4
} MT V'!Zxs
3Y s|M%N
privatestaticint getEveryPage(int everyPage){ f5yd2wKy6
return everyPage == 0 ? 10 : everyPage; FF/MTd}6qG
} 6?KsH;L9
{2q
privatestaticint getCurrentPage(int currentPage){ F.\]Hqq
return currentPage == 0 ? 1 : currentPage; ++kiCoC
} ,)Q mQ^/
r1=Zoxc=w
privatestaticint getBeginIndex(int everyPage, int ;=n7 Z
9:kb0oBa?l
currentPage){ 8F@6^9C
return(currentPage - 1) * everyPage; (Ux%7H_d
} $ &^
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yx}:Sgv%
privatestaticint getTotalPage(int everyPage, int `V?{
>Ek`PVPD
totalRecords){ k(7!W
int totalPage = 0; gF%ad=xm
Q!Op^4Jz
if(totalRecords % everyPage == 0) 9YvMJ
totalPage = totalRecords / everyPage; leD?yyjw7
else Bf-&[ 5N}
totalPage = totalRecords / everyPage + 1 ; i\<l&W
=9)ypI-2
return totalPage; =*(d+[_
} @TH \hr]
M)LdGN?$
privatestaticboolean hasPrePage(int currentPage){ BHK_=2WYz
return currentPage == 1 ? false : true; vAVoFL
} GN>T }
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privatestaticboolean hasNextPage(int currentPage, WK=!<FsC$
1/{:}9Z@
int totalPage){ 2HTZ,W
return currentPage == totalPage || totalPage == I @z{Gr
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0 ? false : true; 6=kd4'yV
} ]c5Shj5|p
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} uj]GBo=
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P_?1Rwm-45
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。 [lnN~#(Y
T[7DJNdG6
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 Jz-f1mhQV
J]~3{Mi
做法如下: *U]f6Q<X
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'Wi*[
Y Jv{Z^;M
的信息,和一个结果集List: I%(+tJ
java代码: 3oIoQj+D
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/*Created on 2005-6-13*/
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package com.adt.bo; \UE9Ff+{
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import java.util.List; s9'iHe
/|\`NARI
import org.flyware.util.page.Page;
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/** OI-%Ig%C#l
* @author Joa ,wFLOfV@
*/ 'shOSB
publicclass Result { ?Cu$qE!h)[
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private Page page; XkNi'GJf
wY=ky629
private List content; s+CWyW@
E+01"G<Q
/** lz>5bR'
* The default constructor +&t{IP(?
*/ ?ph"|LyL
public Result(){ MKH7d/x
super(); ' 1mygplW
} HL)1{[|`
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/** *$s)p >
* The constructor using fields eHjR/MMr_
* [&39Yv.k,7
* @param page q3I,3?_
* @param content sF|lhLi
*/ d82IEhZ#
public Result(Page page, List content){ nyDqR#t
this.page = page; ~{N|("nB
this.content = content; 7i'vAOnw^
} v` B_xEl
+I/P5OGRN
/** aE;!mod
* @return Returns the content. ^@)+P/&
*/ Y<|L|b6
publicList getContent(){ 9sRP8Nj|
return content; ]]]7"a
} -x RsYYw
UIyOn` d "
/** |M0TG
* @return Returns the page. c#rbyx?5
*/ 7IvCMb&%R
public Page getPage(){ yRy9*r=
return page; In 1.R$O
} --]\z* x
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/** "zv+|_ZAfd
* @param content $]hf2Yr(
* The content to set. ))MP]j9
T
*/ BY 1~\M
public void setContent(List content){ S#""((U$
this.content = content; CsE|pXVG
} HPgMVp'
Jv7M[SJ#x
/** |Rl|Th
* @param page u!X2ju<
* The page to set. mq
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*/ A#p@`|H#B
publicvoid setPage(Page page){ ;Lu}>.t
this.page = page; 9\"~ G)
} 6HEl1FK{@
} 0m@S+$v
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A8A+ImwO"
uIba{9tM"P
2. 编写业务逻辑接口,并实现它(UserManager, RJ-CWt
[LG
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UserManagerImpl) me9RnPe:
java代码: )WzCUYE 1/
qVY\5`f@
w68qyG|wM
/*Created on 2005-7-15*/ Tq?W @DM*
package com.adt.service; q`\lvdl
>:K3y$]_
import net.sf.hibernate.HibernateException; c1z5t]d
N1SR nJu<f
import org.flyware.util.page.Page; /
)EB~|4']
gF:wdcO
import com.adt.bo.Result; A^m hPBT_
0(..]\p^d
/** Wd%j;glG
* @author Joa C=Zuy^
*/ Nd0Wt4=
publicinterface UserManager { weDv[b5i
\Z~m6;
public Result listUser(Page page)throws oW8[2$_N+
D2hvf^g'*
HibernateException; M,[ClQ 9
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} !cq4+0{O;&
Sj*H4ZHD<&
< ^&'r5H
|n~v_V2.0
HY42G#^
java代码: Wqqo8Y~fq
%Wc-.ER
EXzY4D ^
/*Created on 2005-7-15*/ j^k{~]+_^]
package com.adt.service.impl; LQS*/s0
NN$`n*;l
import java.util.List; &wjOb
K}zw%!ex
import net.sf.hibernate.HibernateException; 1"k
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import org.flyware.util.page.Page; O-|3k$'\z
import org.flyware.util.page.PageUtil; G' b p
4gZN~_AI<
import com.adt.bo.Result; D QRt\!
import com.adt.dao.UserDAO; ' ZB%McS
import com.adt.exception.ObjectNotFoundException; f]hW>-B(q
import com.adt.service.UserManager; (Hsfrc
Ne4A
/** ^.4<#Qs
* @author Joa NfSe(rd
*/ NT nn!k
publicclass UserManagerImpl implements UserManager { ZqhINM*Rm
k82'gJ;MC=
private UserDAO userDAO; n2QD*3i
>SzTZ3!E
/** ;P{ *'@
* @param userDAO The userDAO to set. 4bKZ@r%
*/ *zx;81X=
publicvoid setUserDAO(UserDAO userDAO){ v14[G@V~\
this.userDAO = userDAO; x_Z~k
} 6ZM<M7(V
qR1ez-#K
/* (non-Javadoc) q}8R>`Z{
* @see com.adt.service.UserManager#listUser ~!uK;hI
`j2z=5
(org.flyware.util.page.Page) 6m{3GKaW~
*/ 63~i6
public Result listUser(Page page)throws \ pq]q
\gzNMI*
HibernateException, ObjectNotFoundException { g_q{3PW.
int totalRecords = userDAO.getUserCount(); HS2)vd@)
if(totalRecords == 0) )oNomsn
throw new ObjectNotFoundException &oR&NKk
Qejzp/2
("userNotExist"); yZ2,AR%
page = PageUtil.createPage(page, totalRecords); MdPwuXI
List users = userDAO.getUserByPage(page); lyT~>.?{
returnnew Result(page, users); ND`~|6yb
} 2vur_`cV
"'8$hV65.p
} vbWX`skU
;^xku%u
UR\*KR;yM
DS^Q0 f
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5H5<ft,
dW=]|t&
询,接下来编写UserDAO的代码: Io:xG6yG
3. UserDAO 和 UserDAOImpl: ._nhW*
java代码: }X`K3sk2/z
.$r(":A#)
S5XFYQ
/*Created on 2005-7-15*/ .z9JoQ
package com.adt.dao; #A|MNJ%m
Axcm~!uf
import java.util.List; ZA# jw 8F
4[(P>`Unx
import org.flyware.util.page.Page; 6dNo!$C^
;+5eE`]a/L
import net.sf.hibernate.HibernateException; )D@
NX/}
4A*'0!H
/** :|Z*aI]9
* @author Joa Nc7YMxk'H
*/ .IgCC_C9
publicinterface UserDAO extends BaseDAO { A /o=a#
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publicList getUserByName(String name)throws w</kGK[O
@1kA%LLK
HibernateException; {>~|xW
0h5T&U]${Y
publicint getUserCount()throws HibernateException; NTn-4iJy
P!-9cd1C,
publicList getUserByPage(Page page)throws +`9T?:fu
HWc=.Qq
HibernateException; kmuF*0Bjk
%II |;<
} =T+<>/[
jbG #__#_
~< k'{
8J>s|MZ
.<tb*6rX>
java代码: PB`94W
)Z]8SED
9 Z4H5!:(
/*Created on 2005-7-15*/
T%:}/@
package com.adt.dao.impl; YUc&X