Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?;.+A4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "d^lS@~
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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 J<P/w%i2
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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"74HZO>
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分页支持类: $m%/veD k
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java代码: B8#f^}8
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package com.javaeye.common.util; HIp {< M3
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import java.util.List; fS$Yl~-m?
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publicclass PaginationSupport { NN pa69U
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publicfinalstaticint PAGESIZE = 30; 1.OXkgh
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privateint pageSize = PAGESIZE; TX5/{cHd
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privateList items; c.me1fGn
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privateint totalCount; FVLA^$5c
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privateint[] indexes = newint[0]; nh.v?|
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privateint startIndex = 0; 8w@jUGsc
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public PaginationSupport(List items, int >a]
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totalCount){ oO9iB:w
setPageSize(PAGESIZE); PL B=%[
setTotalCount(totalCount); U?m?8vhR6(
setItems(items); _@3O`
setStartIndex(0); 5<ya;iK
} 9mtC"M<
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public PaginationSupport(List items, int u^eC
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totalCount, int startIndex){ _xwfz]lb+
setPageSize(PAGESIZE); <qj@waKw4
setTotalCount(totalCount); KqIe8bi^G
setItems(items); gRd1(S
setStartIndex(startIndex); 5TW<1'u
} -`<N,
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public PaginationSupport(List items, int Dg4^
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totalCount, int pageSize, int startIndex){ RPqn#B
setPageSize(pageSize); ZFw743G
setTotalCount(totalCount); @[N~;>
setItems(items); si4=C
setStartIndex(startIndex); w0>)y-
} [~H`9Ab=
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publicList getItems(){ $R}iL
return items; :r+
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} ^\t">NJ^
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publicvoid setItems(List items){ )W7H{#
this.items = items; ;7{wa]
} hzVr3;3Zn
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publicint getPageSize(){ F>{uB!!L4
return pageSize; BP><G^
} y,eoTmaI
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publicvoid setPageSize(int pageSize){ ;Cpm3at
this.pageSize = pageSize; <^$b1<@
} GdwHm
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publicint getTotalCount(){ fH{$LjH(
return totalCount; xo3)dsX
} X7!A(q+h
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publicvoid setTotalCount(int totalCount){ Xst}tz62F
if(totalCount > 0){ ApB'O;5
this.totalCount = totalCount; <1K:
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int count = totalCount / ol>=tk 8}
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pageSize; {-Oc8XI/
if(totalCount % pageSize > 0) Eu_0n6J
count++; C/#/F#C
indexes = newint[count]; 4h@of'
for(int i = 0; i < count; i++){ g5]DA.&(
indexes = pageSize * *\5H\s9<
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i; 1KEPD@0oxx
} [_GR'x'0x
}else{ M#IR=|P]
this.totalCount = 0; ?AH<y/i<Y
} e
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} g4932_tC
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publicint[] getIndexes(){ 3Sb%]f5(
return indexes; :zZM&r>
} z>q_]U0
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publicvoid setIndexes(int[] indexes){ "A$Y)j<#G
this.indexes = indexes; ^E8Hv
} L^Af3]]2
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publicint getStartIndex(){ g[Y$SgJ
return startIndex; dv>zK#!
} iTyApLV
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publicvoid setStartIndex(int startIndex){ 5rhdm?Ls0
if(totalCount <= 0) \%*y+I0>
this.startIndex = 0; /qY(uPJ
elseif(startIndex >= totalCount) ~~
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this.startIndex = indexes t38T0Ao
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[indexes.length - 1]; ]5L3[A4Vu
elseif(startIndex < 0) 'S
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this.startIndex = 0; {uG_)G Fr0
else{ 7~f l4*
this.startIndex = indexes A) .AAr
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[startIndex / pageSize]; rGO3
} d":{a6D*d
} 'f!Jh<i
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publicint getNextIndex(){ Mqy`j9FbL
int nextIndex = getStartIndex() + Ku# _
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pageSize; 1A
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if(nextIndex >= totalCount) =ye}IpC*M
return getStartIndex(); [\p0eUog/
else UJ&,9}L8
return nextIndex; N:zSJW`1
} 1 ErYob.p
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publicint getPreviousIndex(){ h Nwb.[
int previousIndex = getStartIndex() - U3QnWPt}>
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pageSize; @
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if(previousIndex < 0) :zoX
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return0; 'LI)6;Yc
else mLqm83
return previousIndex; O@$i
} C\[UAxZ3X
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} oE&[W>,x
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抽象业务类 R&p5 3n
java代码: XDQ1gg`
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/** <k1gc,*
* Created on 2005-7-12 4 n(
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*/ W525:h52{
package com.javaeye.common.business; pQi -
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import java.io.Serializable; wOP}SMn
import java.util.List; l@
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x@ )u:0
import org.hibernate.Criteria; HmKE>C/
import org.hibernate.HibernateException; ySZ)yT
import org.hibernate.Session; R(fR1
import org.hibernate.criterion.DetachedCriteria; vYkoh/(/u
import org.hibernate.criterion.Projections; Dr<Bd;)
import u8QX2|
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org.springframework.orm.hibernate3.HibernateCallback; 5=\b+<pE
import AnQRSB (
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org.springframework.orm.hibernate3.support.HibernateDaoS i\b2P2
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upport; a6C~!{'nW
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import com.javaeye.common.util.PaginationSupport; <T>f@Dn,
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public abstract class AbstractManager extends ^q$sCt}
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HibernateDaoSupport { t!LvV.g+
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privateboolean cacheQueries = false; :>z0m0nI\
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privateString queryCacheRegion; C;|Ru*
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publicvoid setCacheQueries(boolean tee%E=P
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cacheQueries){ &H6Fkza;4
this.cacheQueries = cacheQueries; bVym
} ;nbvn
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publicvoid setQueryCacheRegion(String 6IA~bkc}
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queryCacheRegion){ e BPMT
this.queryCacheRegion = "A7tb39*
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queryCacheRegion; <\u%ZB
} QQcJUOxT9
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publicvoid save(finalObject entity){ 9j/B3CjW
getHibernateTemplate().save(entity); Fa8>+
} |dO1w.x/
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publicvoid persist(finalObject entity){ 8oK30?
getHibernateTemplate().save(entity); e5dw q
} w$_ooQ(_;Q
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publicvoid update(finalObject entity){ {v(3[7
getHibernateTemplate().update(entity); 8@!SM
} ouujd~b+
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publicvoid delete(finalObject entity){ RAvV[QkT
getHibernateTemplate().delete(entity); e2>gQ p/
} 6xwC1V?:0t
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publicObject load(finalClass entity, 5we1q7
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finalSerializable id){ \|kU{d0
return getHibernateTemplate().load ry:tL0;;e#
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(entity, id); zK}.Bhj#
} -7CkOZT
n']@Spm
publicObject get(finalClass entity, x~
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finalSerializable id){ 1'h?qv^(
return getHibernateTemplate().get )<+Z,6
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(entity, id); &}WSfZ0{
} gxF3gM
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publicList findAll(finalClass entity){ qzq>C"z\Y$
return getHibernateTemplate().find("from u >x2
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" + entity.getName());
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} A\:M}D-(
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publicList findByNamedQuery(finalString xZ .:H&0G
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namedQuery){ sD
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return getHibernateTemplate ;kdJxxUox
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().findByNamedQuery(namedQuery); JAYom%A"
} wI)W:mUZZ
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publicList findByNamedQuery(finalString query, 3=`UX
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finalObject parameter){ >t.I,Zn
return getHibernateTemplate x\)-4w<P
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().findByNamedQuery(query, parameter); ?P}7AF
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} 4o'0lz]
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publicList findByNamedQuery(finalString query, dz?:)5>I
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finalObject[] parameters){ :[Fwc
return getHibernateTemplate o +&/ N-t
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().findByNamedQuery(query, parameters); }V09tK/M
} *5wb8[
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publicList find(finalString query){ 9n1O@~
return getHibernateTemplate().find =5+:<e,&
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(query); xHHG|
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} U4%P0}q/
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publicList find(finalString query, finalObject J-=&B5"O>
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parameter){ LFtnSB8
return getHibernateTemplate().find N"T+.
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(query, parameter); ~zi&u46
} l]GLkE
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public PaginationSupport findPageByCriteria ktnsq&qNL
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(final DetachedCriteria detachedCriteria){ 21W>}I"0?
return findPageByCriteria @qI^xs=Z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); PE-VxRN)
} -GQ`n01
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public PaginationSupport findPageByCriteria wTqgH@rGtR
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(final DetachedCriteria detachedCriteria, finalint *&!&Y*Jzg
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startIndex){ U",kAQY
return findPageByCriteria {o AJL
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(detachedCriteria, PaginationSupport.PAGESIZE, t '* L,
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startIndex); j&u{a[Y/}
} K%)u zP
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public PaginationSupport findPageByCriteria 2e#hJ-/`-
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(final DetachedCriteria detachedCriteria, finalint ("ql//SL
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pageSize, *$Bx#0J8
finalint startIndex){ qo/`9%^E?
return(PaginationSupport) #Mrof9
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getHibernateTemplate().execute(new HibernateCallback(){ b@"#A8M
publicObject doInHibernate Nn>Oq+:
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(Session session)throws HibernateException { uL`_Sdjw
Criteria criteria = k,OP*M
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detachedCriteria.getExecutableCriteria(session); v:|_!+g:
int totalCount = )$XcO]
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((Integer) criteria.setProjection(Projections.rowCount [<rV
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()).uniqueResult()).intValue(); "K;f[&xO,o
criteria.setProjection |L,_QXA2
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(null); 67?O}~jbG
List items = 8k vG<&D
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criteria.setFirstResult(startIndex).setMaxResults !o1+#DL)MU
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(pageSize).list(); !E#FzY!}Pl
PaginationSupport ps = nW1u;.
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new PaginationSupport(items, totalCount, pageSize, 5LM Ay"
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startIndex); ~U}0=lRVS
return ps; 8`Ih>
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} |ZC@l^a7
}, true); x5jd2wSDx
} #%5[8~&
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public List findAllByCriteria(final &P' d&B1
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DetachedCriteria detachedCriteria){ ?g+uJf
return(List) getHibernateTemplate z>}H[0[#
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().execute(new HibernateCallback(){ =jz [}5
publicObject doInHibernate )jm!bR`
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(Session session)throws HibernateException { b
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Criteria criteria = 4z6kFQgu
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detachedCriteria.getExecutableCriteria(session); @` 5P^H7
return criteria.list(); pV[SY6/
} ;iq H:wO
}, true); { 0?^ $R8j
} t.X8c/,;g
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public int getCountByCriteria(final &Zy%Zz
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DetachedCriteria detachedCriteria){ [SJ3FZ<
Integer count = (Integer) #7v=#Jco
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getHibernateTemplate().execute(new HibernateCallback(){ pm` f?Py
publicObject doInHibernate oDW)2*8yF
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(Session session)throws HibernateException { D qu?mg;L
Criteria criteria = ;T hn C>U
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detachedCriteria.getExecutableCriteria(session); @5}(Y( @
return rUn1*KWbE
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criteria.setProjection(Projections.rowCount ^J~5k,7jX
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()).uniqueResult(); ?
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} y?OK#,j
}, true); 'u}OeS"f
return count.intValue(); ze"`5z26|
} _D"V^4^yqu
} hik.c3
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用户在web层构造查询条件detachedCriteria,和可选的 =[do([A
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <5O:jd
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PaginationSupport的实例ps。 &[b(Lx|i
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ps.getItems()得到已分页好的结果集 s7?d_+O
ps.getIndexes()得到分页索引的数组 #KUNZW
ps.getTotalCount()得到总结果数 T3bYj|rh=
ps.getStartIndex()当前分页索引 weH;,e*r
ps.getNextIndex()下一页索引 aOhi<I`*
ps.getPreviousIndex()上一页索引 lK Ry4~O
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 zX8'OoEH*9
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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 Y>2oU`ly,
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一下代码重构了。 h^v+d*R
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我把原本我的做法也提供出来供大家讨论吧: 'i:S=E
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首先,为了实现分页查询,我封装了一个Page类: xey?.2K1A
java代码: * `3+x
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/*Created on 2005-4-14*/ {Q021*xt/
package org.flyware.util.page; bQ`2ll*(
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/** 0ky3rFSh1
* @author Joa 1VA%xOURh
* m`&6[[)6~
*/ Z x&= K"
publicclass Page { $C
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/** imply if the page has previous page */ '
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privateboolean hasPrePage; ,a3M*}Y~3
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/** imply if the page has next page */
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privateboolean hasNextPage; [{PmU~RMYf
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/** the number of every page */ J9);(
privateint everyPage; awgS5We|
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/** the total page number */ _b!
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privateint totalPage; LIRL`xU7
, }B{)
/** the number of current page */ \iH\N/
privateint currentPage; ^Sc48iDc
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/** the begin index of the records by the current r!c7{6N
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query */ 7I0K=
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privateint beginIndex; &; [0.:;
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/** The default constructor */ Z8:'_#^@a[
public Page(){ )U+&XjK
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} Ai~d
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/** construct the page by everyPage \|7Y"WEQ
* @param everyPage 3uuB/8
* */ 6'|NALW
public Page(int everyPage){ `L
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this.everyPage = everyPage; |?LUt@r;
} VrKFpFd
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/** The whole constructor */ Mb+CtI_'
public Page(boolean hasPrePage, boolean hasNextPage, ]Z>zf]<
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int everyPage, int totalPage, )QB9zl:
int currentPage, int beginIndex){ %(~8a
this.hasPrePage = hasPrePage; b/UjKNf@
this.hasNextPage = hasNextPage; jN%+)Kj0C)
this.everyPage = everyPage; L[Y|K%;~
this.totalPage = totalPage; J';XAB }
this.currentPage = currentPage; cJ#%OU3p
this.beginIndex = beginIndex; lT+N{[kLt*
} 6AKT-r.
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/** TnLblkX
* @return 0E`6g6xMS
* Returns the beginIndex. GD<pqm`vVY
*/ *h~(LH"tN
publicint getBeginIndex(){ VMW<?V
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return beginIndex; hQLh}}B
} S %(R9N|
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/** trg&^{D<
* @param beginIndex CW@G(R
* The beginIndex to set. &\Yd)#B/
*/ 8Og)(BC
publicvoid setBeginIndex(int beginIndex){ 7WN$ rl5/
this.beginIndex = beginIndex; vW03nt86
} D,SL_*r{
?sbM= oo
/** KDYyLkI dr
* @return C72btS
* Returns the currentPage. P"k,[ZQ
*/ 1#jvr_ ga
publicint getCurrentPage(){ _R;+}1G/
return currentPage; ^jg{MTa
} dMoN19F
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/** Kvh6D"
* @param currentPage YL@d+
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* The currentPage to set. \?NT,t=3J
*/ ?]2OT5@&s
publicvoid setCurrentPage(int currentPage){ D;OR?NdgvW
this.currentPage = currentPage; 3bMUsyJ 2
} !'
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/** $:<G=
* @return \:-N<[
* Returns the everyPage. ATf{;S}
*/ (1}"I
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publicint getEveryPage(){ -O>*`
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return everyPage; 2O)2#N
} W'M\DKJ?
l|K`'YS!<{
/** ZUUfn~ORc
* @param everyPage Y\ G^W8
* The everyPage to set. :@q9ll`6u
*/ nwAx47>{
publicvoid setEveryPage(int everyPage){ XrQS?D`
this.everyPage = everyPage; :Qklbd[9qF
} (?pn2- Ip
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/** ! jb{q bq
* @return von~-51;
* Returns the hasNextPage. ~*uxKEH
*/ fY9/u =
publicboolean getHasNextPage(){ /'0,cJnm
return hasNextPage; dM3V2TT
} 0B[eG49
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/** 5zsXqBG
* @param hasNextPage .
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* The hasNextPage to set. 9C)w'\u9+
*/ i4oBi]$T
publicvoid setHasNextPage(boolean hasNextPage){ Zc57] ~
this.hasNextPage = hasNextPage; 3a#j&]
} o'nrLI(t
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/** 7&9'=G
* @return wq"AW yu
* Returns the hasPrePage. D^H<)5d9
*/ vH^^QI:em
publicboolean getHasPrePage(){ me`(J y<
return hasPrePage; $[P>nRhW
} JTg0T+
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/** rKys:is
* @param hasPrePage :cK;|{f
* The hasPrePage to set. R0*+GIRA(
*/ O[fgn;@|
publicvoid setHasPrePage(boolean hasPrePage){ ]]Da/^K=Z
this.hasPrePage = hasPrePage; +kTa>U<?
} }qOC*k:
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/** 0IEFCDeCO
* @return Returns the totalPage. ^R4eW|H
* k6 f;A
*/ |79!exVMBp
publicint getTotalPage(){
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return totalPage; x9NLJI21/
} GcPhT
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/** uz+b
* @param totalPage p
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* The totalPage to set. fE/8;v!=
*/ -j_J1P0,
publicvoid setTotalPage(int totalPage){ 8}W06k>)%
this.totalPage = totalPage; :1wMGk
} ?y{C"w!
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} UI:{*N**Z
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 (&$|R\W.
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个PageUtil,负责对Page对象进行构造: Mr(~
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java代码: 41TB
9c=_p'G3Fw
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/*Created on 2005-4-14*/ ?WX&,ew~
package org.flyware.util.page; Zh.fv-Ecp
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import org.apache.commons.logging.Log; $0Y&r]'
import org.apache.commons.logging.LogFactory; 0PnW|N0
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/** z~xN]=
* @author Joa j]<T\O>t>
* 0\jOg
*/ 3Fn26Rij
publicclass PageUtil { v|Tg %
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privatestaticfinal Log logger = LogFactory.getLog |Tz4 xTK
q$`:/ ehw
(PageUtil.class); LxVd7r VY6
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/
/** D.<CkDB
* Use the origin page to create a new page &hba{!`y
* @param page WL}6YSC
* @param totalRecords iEki<e/
* @return 7`tnoTUv
*/ _A)<"z0E
publicstatic Page createPage(Page page, int XI\aZ\v
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totalRecords){ 9VN@M
return createPage(page.getEveryPage(), <E
BgHD)
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page.getCurrentPage(), totalRecords); (`18W1f5W
} c`X'Q)c&K
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/** g#_?Vxt
* the basic page utils not including exception u6y\ GsM.a
%i%Xi+{3
handler 1qUdj[Bj
* @param everyPage }]zmp/;a
* @param currentPage GGF;T&DWad
* @param totalRecords {zUc*9
* @return page "\BP+AF
*/ P+3G*M=}
publicstatic Page createPage(int everyPage, int ".xai.trr
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currentPage, int totalRecords){ %1VMwqC]E
everyPage = getEveryPage(everyPage); MQY1he2M
currentPage = getCurrentPage(currentPage); %T6#c7U_
int beginIndex = getBeginIndex(everyPage, *!9/`zW
].dTEzL9X
currentPage); y=vH8D]%X
int totalPage = getTotalPage(everyPage, e^Xij Id.
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totalRecords); q 8=u.T
boolean hasNextPage = hasNextPage(currentPage, bOck^1Hk y
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3m1
totalPage); MmWJYF=
boolean hasPrePage = hasPrePage(currentPage); &OhKx
o@LjSQ5!
returnnew Page(hasPrePage, hasNextPage, &"tce6&
everyPage, totalPage, \ @N> 38M
currentPage, P>@`hZ9
o
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beginIndex); F41!Dj7
} P1)
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privatestaticint getEveryPage(int everyPage){ fr#lH3
return everyPage == 0 ? 10 : everyPage; `8dE8:#Y
} Xp} vJl
~#a1]w
privatestaticint getCurrentPage(int currentPage){ @IiT8B
return currentPage == 0 ? 1 : currentPage; HnP;1Gi
} oLr"8R\d>t
!W%HAlUAG[
privatestaticint getBeginIndex(int everyPage, int X^|oY]D
zK-hNDFL{
currentPage){ (uG4W|?p
return(currentPage - 1) * everyPage; D8?$Fn=
} BRD'5 1]|
}uHc7gTBF7
privatestaticint getTotalPage(int everyPage, int a ^)Mx9
b(Z%#*e
totalRecords){ n/,7ryu
int totalPage = 0; k@8#By l|
|O4A+S
if(totalRecords % everyPage == 0) .@6]_h;
totalPage = totalRecords / everyPage; +cV!=gDT
else (J$A
totalPage = totalRecords / everyPage + 1 ; owMH
@6j*XF
return totalPage; #>v7"
<
} pz&=5F
jujx3rnK?
privatestaticboolean hasPrePage(int currentPage){ D} .t
return currentPage == 1 ? false : true; d(@A
} +1)C&:
9>i6oF]Oq
privatestaticboolean hasNextPage(int currentPage, L\Jl'r|
Pm1
"
0
int totalPage){ @Qs-A^.
return currentPage == totalPage || totalPage == 1=;QWb6
m|]^f;7z
0 ? false : true; D+SpSO7yg
} Nr[Rp
\OU+Kl<
YjX=@
} 42wcpSp
Mb>6.l
CD&m4^X5D
AltE~D/4
+uLo~GdbE
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。 87^
4",
Agi1r]W
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 *cf"l
8zc!g|5"
做法如下: +
kF[Oh#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 P+b^;+\1s
%b{!9-n}
的信息,和一个结果集List: ^ Wl/
java代码: *.*:(7`
DO\EB6xH>%
J7\q#] ?
/*Created on 2005-6-13*/ mN eW|3a
package com.adt.bo; x>J3tp$2
WvJ?e
import java.util.List; Pu^~]^W)
5i^vN"J
import org.flyware.util.page.Page; tbPPI)lu
(Z$6JNkz
/** >o} ati
* @author Joa s =5H.q%PV
*/ yhdG 93
publicclass Result { bvgD;:Aj
O2,g]t~C
private Page page; W<LaR,7
>ek%P;2w>
private List content; od}x7RI%m
{@#L'i|
/** /K!,^Xn
* The default constructor 68c;Vb
*/ Cv~hU%1T
public Result(){ Qf|}%}%fp
super(); "?{yVu~9
} VjqdKQeVq
S1zw'!O5
/** S<_pGz$V
* The constructor using fields nwo!A3w:
* IA^)`l 7H
* @param page I.u,f:Fl'
* @param content |+:ZO5FaO
*/ D%idlL2%J
public Result(Page page, List content){ 4LjSDgA
this.page = page; oPy zk7{
this.content = content; ]R{"=H'
} \Ep/'Tj&
fE*I+pe
/** na3kHx@
* @return Returns the content. D&r8V;G[[
*/ W[>Tq T63
publicList getContent(){ |I}+!DDuv
return content; }AiS83B
} YhT1P fl
nh=Us^xD
/** VQ?H:1R
* @return Returns the page. x#0@$
*/ QiweM?-
public Page getPage(){ 'Xl>,\'6
return page; IJc#)J.2A
} _~nex,;r
R{o*O_qX
/** #@6L|$iX
* @param content >1U@NK)HfY
* The content to set. D:ugP,
*/ otVyuh
public void setContent(List content){ S.)7u6/_!
this.content = content; N&ql(#r
} ,;P`Mf'YC
\u_v7g
/** gwaC?tf[
* @param page /mwr1GU
* The page to set. un^IQMIh
*/ thPH_DW>eb
publicvoid setPage(Page page){ !;*2*WuO;
this.page = page; \ui^
d
} 6J-}&U
} eH!|MHe
A] ?O&m|
c;rp@_ULG?
U\8#Qvghf
q7 oR9
2. 编写业务逻辑接口,并实现它(UserManager, [E~,> Q
EjX'&"3.
UserManagerImpl) x0A%kp&w
java代码: cNr][AzU@
<Ihed|
mjl!Nth:<
/*Created on 2005-7-15*/ n{Qh8"
package com.adt.service; 3d'ikkXK
y [9}[NMZ
import net.sf.hibernate.HibernateException; A%*DQ1N
R,w54},
import org.flyware.util.page.Page; T :S{3
Zc3:9
import com.adt.bo.Result; 5652'p
Z^`=!n-V
/** g}
~<!VpX
* @author Joa 3:8nwt
*/ 4Eh BpTg
publicinterface UserManager { :$cSQ(q9a
a H|OA\<
public Result listUser(Page page)throws K@sP~('
_{`'{u
HibernateException; ]AC!R{H
K# i*9sM
} )~blx+ \y
'Tf#S@o
30(m-D$K>9
r{!"%03H_
uU ?37V
java代码: 9poEUjBI
wz0$g4
fpK0MS]=b
/*Created on 2005-7-15*/ g.Caapy
package com.adt.service.impl; B
mBzOk^
/yw\(|T
import java.util.List; 8@W/43K8-
dI
ZTLb"a
import net.sf.hibernate.HibernateException; C3b0`|5
mf]( 3ZL
import org.flyware.util.page.Page; X\^& nLa
import org.flyware.util.page.PageUtil; svq9@!go
t2-nCRXEP
import com.adt.bo.Result; k`7.p,;}U
import com.adt.dao.UserDAO; zUEfa!#?
import com.adt.exception.ObjectNotFoundException; 4=F]`Lql
import com.adt.service.UserManager; `\|3
~_v
_/]:=_bf_z
/** G\:psx/
* @author Joa t1:S!@
*/ 8/>wgY
publicclass UserManagerImpl implements UserManager { $>h!J.t
rGn5QV
private UserDAO userDAO; %hQMC'c
kk/+Vx~
/** J<($L}T*$
* @param userDAO The userDAO to set. nhQ44qRgQ
*/ AeY$.b
publicvoid setUserDAO(UserDAO userDAO){ %is,t<G
this.userDAO = userDAO; ny
} 3dX=xuQ%/
@1/}-.(n
/* (non-Javadoc) jgo<#AJ/E
* @see com.adt.service.UserManager#listUser f.$aFOn
^!o1l-Y^gr
(org.flyware.util.page.Page) }* B qi7E>
*/ KXx@
{cv
public Result listUser(Page page)throws PQ&Q71
/_:T\`5uO
HibernateException, ObjectNotFoundException { DUuC3^R
int totalRecords = userDAO.getUserCount(); {glqWFT
if(totalRecords == 0) A"BtVy[[9
throw new ObjectNotFoundException V6z@"+
wHt#'`5
("userNotExist"); uzVG q!'H
page = PageUtil.createPage(page, totalRecords); I_zk'
List users = userDAO.getUserByPage(page); D*XZT{1g
returnnew Result(page, users); g]==!!^<D
} $||ns@F+
RI5g+Du?
} lC /Hib
ET,0ux9F
0V>ESyae5
X@bn??
QWzOp\+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 r(,= uLc
da9*9yN
询,接下来编写UserDAO的代码: clq~ ;hx
3. UserDAO 和 UserDAOImpl: DYT@BiW{
java代码: yBPt%EF
}rKJeOo^x?
,#P,B;r~
/*Created on 2005-7-15*/ &Hlm{FHU
package com.adt.dao; 7z/(V\9B
+(=0CA0GE
import java.util.List; Qc&-\kQ:$u
SLQ\Y%F
import org.flyware.util.page.Page; SG
dfhno;
wr3_Bf3]
import net.sf.hibernate.HibernateException; xs2,t*
j[m_qohd7
/** IDGQIg
* @author Joa |5}rX!wS4
*/ vgh^fa!/
publicinterface UserDAO extends BaseDAO { j.=UI-&m
|<j,Tr1[
publicList getUserByName(String name)throws !"`@sd~
-~vl+L
HibernateException; RjR&D?dc
C@TN5?Z
publicint getUserCount()throws HibernateException; ,>bGbx
[)Z'N/;0
publicList getUserByPage(Page page)throws '!j #X_;
C=oM,[ESQ0
HibernateException; `2B*CMW{
p4m^ ~e
} 1a($8>
,2 zt.aqB
`G=ztL!gq
H4PbO/{xO
toS(UM n
java代码: Q vv\+Jp^
p3M#XC_H]
rxs~y{Xi
/*Created on 2005-7-15*/ Z&+NmOY4
package com.adt.dao.impl; /v}P)&
zuC 58B
import java.util.List; e-[>( n/[
5y1or
import org.flyware.util.page.Page; g
,/a6M
D~G5]M,}$
import net.sf.hibernate.HibernateException; ]}mly`Fw
import net.sf.hibernate.Query; d\~p5_5.
L.C
^E7;Z_
import com.adt.dao.UserDAO; U}tl_5%)
x4CtSGG85f
/** BA~a?"HS
* @author Joa T"L0Iy!k;
*/ CCbkxHMf|!
public class UserDAOImpl extends BaseDAOHibernateImpl .dD9&n;#^
B<|:K\MA
implements UserDAO { .ocx(_3G
Zu\p;!e
/* (non-Javadoc) Q0pC4WJ`
* @see com.adt.dao.UserDAO#getUserByName ?TvQ"Y}k
cZNi~
(java.lang.String) pwJ'3NbS
*/ Ad dGB^7yl
publicList getUserByName(String name)throws q*~gWn>T
k_,MoDz
HibernateException { 5h_<R!jA
String querySentence = "FROM user in class !UBy%DN~k
jP1$qhp
com.adt.po.User WHERE user.name=:name"; bjPka{PBj
Query query = getSession().createQuery K^"w]ii=
I\}|Y+C$d/
(querySentence); z=ML(1c=
query.setParameter("name", name); EKqi+T^=F
return query.list(); lp,\]]
} RY9+ 9i
]vm\3=@}9
/* (non-Javadoc) BX@pt;$ek7
* @see com.adt.dao.UserDAO#getUserCount() q>^hoW2$C
*/
@bY('gC,
publicint getUserCount()throws HibernateException { @O@fyAz
int count = 0; {SF[I
String querySentence = "SELECT count(*) FROM J&A;#<qY
M-{*92y&
|
user in class com.adt.po.User"; }X=87ud
Query query = getSession().createQuery w+q?T
%oAL
(querySentence); M6J/mOVx5
count = ((Integer)query.iterate().next zL9VR;q
~}h^38
()).intValue(); ~_'0]P\
return count; Y.q>EUSH
} o[o:A|n
>R( 8/#|E
/* (non-Javadoc) \M7I&~V
* @see com.adt.dao.UserDAO#getUserByPage {I`B[,*
Xc\*9XV:
(org.flyware.util.page.Page) kt:)W])V
*/ plK=D#)
publicList getUserByPage(Page page)throws OQ6sv/
V/J>GRjw
HibernateException { 3AK(dC[ri
String querySentence = "FROM user in class d4%dIR)
=K .r
com.adt.po.User"; >[a FOA
Query query = getSession().createQuery fGb7=Fk
I[ai:
(querySentence); mKV'jm0
query.setFirstResult(page.getBeginIndex()) 1xz\=HOT
.setMaxResults(page.getEveryPage()); [_h%F,_ A
return query.list(); gF3TwAr
} lY.B
B]1HS`*7
} Yj)
e$f
Xq|nJ|h
WM/#.
Mec{_jiH&D
8 4z6zFv?Q
至此,一个完整的分页程序完成。前台的只需要调用 2
#KoN8%
qtHfz"p
userManager.listUser(page)即可得到一个Page对象和结果集对象 +O'vj
{1~9vHAZ
的综合体,而传入的参数page对象则可以由前台传入,如果用 9SY(EL
JX{KYU
webwork,甚至可以直接在配置文件中指定。 .8]Y-
6_*!|g
下面给出一个webwork调用示例: Kh)FyV
java代码: BBvZeG $Y
L!g DFZr
jPnO@H1
/*Created on 2005-6-17*/ z!:'V]
package com.adt.action.user; y?>#t^
27>a#vCT
import java.util.List; co/7l sW
=N_,l'U\^
import org.apache.commons.logging.Log; DF'8GF&Rp
import org.apache.commons.logging.LogFactory; nX._EC
import org.flyware.util.page.Page; AliRpxxd
_9NVE|c;
import com.adt.bo.Result; ET)>#zp+s
import com.adt.service.UserService; a+41Ojv (
import com.opensymphony.xwork.Action; .jU Z
"<*awWNI
/** -u|l}}bh
* @author Joa -l
"U"U"F
*/ 0 O~p7D
publicclass ListUser implementsAction{ M/{g(|{
:M j_2
privatestaticfinal Log logger = LogFactory.getLog kM!V.e[g
?>V6P_r>
(ListUser.class); Tr&E4e
o'Pu'y
private UserService userService; A
W)a">|
t[EfOQ
private Page page; (;}tf~~r
#.<V^
privateList users; !%xP}{(7
' "'Btxz
/* <qhBc:kc
* (non-Javadoc) .Pw%DZ'
*
-4flV D
* @see com.opensymphony.xwork.Action#execute() ;xK_qBIP
*/ /)9W1U^B
publicString execute()throwsException{ ,)h)5o(?
Result result = userService.listUser(page); B!b sTvX
page = result.getPage(); B
wC+ov=
users = result.getContent(); tWY2o3j
return SUCCESS; o9Sn*p-.
} 1zjaR4Tf
Ax!Gu$K2o
/** <C<`J{X0
* @return Returns the page. z/1{OL
*/ EA|k5W*b
public Page getPage(){ (R'+jWH
return page; O"*`'D|hK
} ni6r{eSQ
2yKz-"E
/** @u)
'yS
* @return Returns the users. 5+P@sD
*/ gLQ #4H
publicList getUsers(){ ^7aN2o3{
return users; >fzwFNdo
} sG,+
[$a<b/4
/** G#[*|+f8
* @param page n.hElgkUOr
* The page to set. }q!_!q,@
*/ E=u/tpj
publicvoid setPage(Page page){ &Y7C0v
this.page = page; KWhZ +i`
} - 8bNQU
}rbZ&IN\?E
/** e*]r
* @param users jtKn3m7 +p
* The users to set. :gI.l1
*/ a3@w|KLt
publicvoid setUsers(List users){ lj2=._@R
this.users = users; tNnyue{p
} ;/LD)$_
u+D[_yd^
/** x*}bo))hb
* @param userService }!)F9r@\
* The userService to set. 8]< f$3.
*/ 0{) $SY
publicvoid setUserService(UserService userService){ 4vdNMV~
this.userService = userService; 'iUg[{'+
} feEMg
} 0^~\COa
SwH2$:f
&ZJgQ-Pc(m
Ip?]K*sq
op7FZHs
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, UG2w 1xqHw
lBA +zZ
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 NY.k.
wJG$c-(\0
么只需要: eW8[I'v_&
java代码: f h<*8w0H
o a<q /
Bct"X#W|&
<?xml version="1.0"?> hI|)u4q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $'"8QOnJ?k
UQT'6* !
1.0//EN" "http://www.opensymphony.com/xwork/xwork- .q;ED`G
Hl7:*]l7b
1.0.dtd"> ijUzC>O+q
:&VcB$
<xwork> xxa} YIe8
O}Le]2'
<package name="user" extends="webwork- -5>NE35Cto
=%qEf
interceptors"> F#V q#|_)>
p-$Cs _{Z
<!-- The default interceptor stack name GsV4ZZ
u oVNK
--> 6Nh0
<default-interceptor-ref d^V$Z6*
]
E9 Y\X
name="myDefaultWebStack"/> HJhH-\{@
S>_27r{
<action name="listUser" ;-@=
;D2E_!N
dt
class="com.adt.action.user.ListUser"> |4b)>8TL/
<param uS5o?fg\e
j9y3hQ+q
name="page.everyPage">10</param> Fu _@!K
<result #a9_~\s
|3eGz%Sd
name="success">/user/user_list.jsp</result>
RiFw?Q+
</action> TbhH&kG)1
;+Yi.Q/\
</package> t})$lM
7_\Mwy{P
</xwork> p1O6+hRio
q<{NO/Mm
O`W%Tr
<GIwRVCU
raB+,Oi$G
83iCL; GS=
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 cFZCf8:zB
`
2%6V)s
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ,x_Z JL
K"{HseN{
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 (> "QVxr
rVryt<2:@r
{aj/HFLNY
%c/^_.
%XRN]tsu
我写的一个用于分页的类,用了泛型了,hoho )]Ti>R O7
s#-eN)1R
java代码: t#~?{i@m
F@vbSFv)/
3 <SqoJSp
package com.intokr.util; y]
V1b{9p
'K@0Wp
import java.util.List; _sMs}?^
r%=[},JQ
/** _p}xZD\?,
* 用于分页的类<br> zFhgE*5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> KSqTY>%fnv
* | {P|.
* @version 0.01 2WCLS{@'
* @author cheng e%6{ME
3
*/ [aW =
public class Paginator<E> { {aDFK;qG.
privateint count = 0; // 总记录数 4zc<GL3[
privateint p = 1; // 页编号 45+{nN[
privateint num = 20; // 每页的记录数 @h?crJ6$
privateList<E> results = null; // 结果 &a)vdlZSE=
kU*{4G|6
/** grcbH
* 结果总数 >SI<rR[~%
*/ e>H:/24
publicint getCount(){ QGPw2Q
return count; ;4~U,+Av
} |:q/Dt@
r6.N4eW.L
publicvoid setCount(int count){ 4\2V9F{s
this.count = count; |!*Xl)
]
} ~!:0iFE&H
\L]|-f(4
/** <$Yi]ty
* 本结果所在的页码,从1开始 f} K`Jm_}?
* l I-p_K
* @return Returns the pageNo. (.X]F_*sc
*/ d>i13dAI
publicint getP(){ 1Ix3i9
return p; XB\zkf_}Xc
} SS3-+<z
p+w8$8)
/** T[uDZYx
* if(p<=0) p=1 s3 QEi^~
* "^rNr_
* @param p wyY*:{lZ
*/ o'=VZT9
publicvoid setP(int p){ 4u1KF:g
if(p <= 0) isK;mU?<
p = 1; ~brFo2
this.p = p; pB01J<@m
} +"!aM?o
B;t=B_oK
/** E_:QSy5G
* 每页记录数量 .{so
*/ 1mW %
publicint getNum(){ hu@7?f_"L/
return num;
9f+RAN(
} 1:NS}r+>3.
Y
62r
/** uHM@h{r
* if(num<1) num=1 >L>+2z
*/ D3]BTkMMS;
publicvoid setNum(int num){ HD-Erop
if(num < 1) XD%wj
num = 1; 46XN3r
this.num = num; 284zmZZ
} 96Zd M=
ltA/
/** PZOKrW
* 获得总页数 a(x?fa[D
*/ v3^|"}\q5
publicint getPageNum(){ 8Qrpa o
return(count - 1) / num + 1; ^Kq|ID
AP
} ^eh/HnJs
HnZPw&*
/** ^ddO&!U
* 获得本页的开始编号,为 (p-1)*num+1 <^><3U`
*/ K0fv( !r{
publicint getStart(){ ;VzMU ;j
return(p - 1) * num + 1; +Ui_ O
} |nxdB&1n
5
2Hqu>
/** v\A.Tyy
* @return Returns the results. '044Vm;/
*/ ]PS\#I}
publicList<E> getResults(){
(_+;R
return results; &8?`<
} Spj9H ?m
kQIw/@WC
public void setResults(List<E> results){ vjlGX T`m
this.results = results; =*MR(b>
} vrIV%l=
2*OxA%QELM
public String toString(){ 8z T0_vw
StringBuilder buff = new StringBuilder &3DK^|Lq
]Yz'8uts
(); !#WqA9<
buff.append("{"); +zO]N&
buff.append("count:").append(count); .Ff_s
buff.append(",p:").append(p); 1f//wk|
buff.append(",nump:").append(num); 8wFn}lw&
buff.append(",results:").append P6Xp<^%E
w|Qd`
(results); S+T|a:]\7
buff.append("}"); X"/~4\tJ"
return buff.toString(); q=0 pQ1>
} %z)EO9vtr
J$[Q?8
ka
} nQLs<]h1
HeS'~Z$
f=_g8+}h