Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 PuxK?bwC
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1! p/6
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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 >QHo@Zqj(
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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 Aa?I8sbc
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分页支持类: qQxz(}REu9
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java代码: .[DthEF
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package com.javaeye.common.util; *QM~O'WhD
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import java.util.List; U,1AfzlF
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publicclass PaginationSupport { %o?IsIys
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publicfinalstaticint PAGESIZE = 30; :L0/V~D
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privateint pageSize = PAGESIZE; %lr|xX
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privateList items; lH|LdlX
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privateint totalCount; R.j1?\
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privateint[] indexes = newint[0]; OlxX.wP
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privateint startIndex = 0; {OT:3SS7
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public PaginationSupport(List items, int 7.<^j[?
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totalCount){
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setPageSize(PAGESIZE); y?30_#[dN
setTotalCount(totalCount); L6
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setItems(items); (I{
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setStartIndex(0); SQE[m9v
} ,6<"
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public PaginationSupport(List items, int rFJ[dz
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totalCount, int startIndex){ ID};<[
setPageSize(PAGESIZE); S"snB/
setTotalCount(totalCount); ,D80/2U^
setItems(items); `PI(%N
setStartIndex(startIndex); XeUC0K[D
} TUp%FJXA|
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public PaginationSupport(List items, int ned2lC&'d>
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totalCount, int pageSize, int startIndex){ #~?kYCtC)
setPageSize(pageSize); eIPG#A
setTotalCount(totalCount); ~@I@} n
setItems(items); m4ApHM2
setStartIndex(startIndex); NB8&
} 1M%S
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publicList getItems(){ ]Ql 0v"` F
return items; OCyG_DLT$5
} !UV5zmS
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publicvoid setItems(List items){ fW0$s`
this.items = items; /k:$l9C[
} 83]PA<R
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publicint getPageSize(){ ]]iO- }
return pageSize; qFRdg V>8
} 96|[}:+$&:
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publicvoid setPageSize(int pageSize){ 0x)dnq\
this.pageSize = pageSize; j033%p+Xc
} p{;i& HNdp
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publicint getTotalCount(){ >kY p%r6
return totalCount; G`]w?Di4
} 8KjRCm,I
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publicvoid setTotalCount(int totalCount){ ysXx%k
if(totalCount > 0){ B0mLI%B
this.totalCount = totalCount; gb-{2p>}
int count = totalCount / AO0!liQ
*:_~Nn9_R;
pageSize; W=-|`
if(totalCount % pageSize > 0) y62%26 [
count++; R"6;NPeo
indexes = newint[count]; 8<PKKDgbfd
for(int i = 0; i < count; i++){ E[Bo4?s&^
indexes = pageSize * k&s; {|!
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} <O857j
}else{ `6w#8}
this.totalCount = 0; (6xDu.u?A
} [e"RTTRfZ
} DvT+`X?R
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publicint[] getIndexes(){ Ky9W/dCR
return indexes; !sIwFv)
} ]rX9MA6
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publicvoid setIndexes(int[] indexes){ tEhr
this.indexes = indexes; OeTu?d&N
} `bP?o
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publicint getStartIndex(){ 2cnj@E:5l
return startIndex; VWvoQf^+
} &IQ%\W#aY
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publicvoid setStartIndex(int startIndex){ f$D@*33ft
if(totalCount <= 0) ;) pl{_
this.startIndex = 0; ~$aTM_4
elseif(startIndex >= totalCount) %!W%#U0
this.startIndex = indexes X8 qIia
T_ ^C#>
[indexes.length - 1]; E$S`6+x`:a
elseif(startIndex < 0) |`]oc,1h@
this.startIndex = 0; |cTpw1%I~
else{ '
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this.startIndex = indexes _X%Dw
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[startIndex / pageSize]; c f*zejbw
} 9) ea.Gu
} <aVfJd/fT
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publicint getNextIndex(){ 1_3?R}$Wl
int nextIndex = getStartIndex() + {8m1dEC^@Q
fv==Gu%{
pageSize; 1P5LH5
if(nextIndex >= totalCount) !J#.!}3
return getStartIndex(); v ($L
else BI/y<6#rR
return nextIndex; ~gt3Omh
} +qE']yzm!
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publicint getPreviousIndex(){ IK?]PmN4}
int previousIndex = getStartIndex() - nEVbfNo0
tp+=0k2i
pageSize; #:
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if(previousIndex < 0) )0|):g
return0; pTET%)3
else Wm>b3:
return previousIndex; BTs0o&}e
} "_)|8|gN
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} d
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抽象业务类 Xu%d,T$G
java代码: Sh$U-ch@
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/** {G.jB/
* Created on 2005-7-12 Z:^3Fm->+
*/ ^srs$
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package com.javaeye.common.business; {rfte'4;=
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import java.io.Serializable; GC?S];PL
import java.util.List; g< )72-h
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import org.hibernate.Criteria; NDW8~lkL
import org.hibernate.HibernateException; {Y"8~
import org.hibernate.Session; ||f vKyKW>
import org.hibernate.criterion.DetachedCriteria; Q
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import org.hibernate.criterion.Projections; m+7`\|`jQ
import q\_DJ)qpn
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org.springframework.orm.hibernate3.HibernateCallback; ` U#Po_hq
import TK %<a/
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org.springframework.orm.hibernate3.support.HibernateDaoS "uS7PplyO
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upport; 3.~h6r5-
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import com.javaeye.common.util.PaginationSupport; xH@'H?
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public abstract class AbstractManager extends _Z.;u0Zp8
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HibernateDaoSupport { .t:DvB
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privateboolean cacheQueries = false; \
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privateString queryCacheRegion; Kt6C43]7
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publicvoid setCacheQueries(boolean 6d};|#}
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cacheQueries){ &58 {
this.cacheQueries = cacheQueries; V0S6M^\DK
} Z !Z,M' "
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publicvoid setQueryCacheRegion(String QSv^l-<
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queryCacheRegion){ *LEu=3lp%>
this.queryCacheRegion = pd7O`.3
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queryCacheRegion;
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} ;9vIa7L&
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publicvoid save(finalObject entity){ k_BSY=$e*D
getHibernateTemplate().save(entity); 3Mxz_~
} q>P[n z%
S_j1=6#^
publicvoid persist(finalObject entity){ C|9[Al
getHibernateTemplate().save(entity); niQ+EAD
} i<bxc
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publicvoid update(finalObject entity){ (<
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getHibernateTemplate().update(entity); |;~nI'0O])
} 1O23"o5=
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publicvoid delete(finalObject entity){ C~{xL>I
getHibernateTemplate().delete(entity); K,G,di
} *^ey]),f54
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publicObject load(finalClass entity, 7x%S](m%
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finalSerializable id){ 48:liR
return getHibernateTemplate().load <3)|44.o&
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(entity, id); :wSJ-\'$
} x<Iy<v7-
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publicObject get(finalClass entity, gj[zka0_
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finalSerializable id){ n$IWoIdbGN
return getHibernateTemplate().get *&h6*zP?
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(entity, id); $]nVr(OZ_
} avmcGyL
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publicList findAll(finalClass entity){ O(WEgz
return getHibernateTemplate().find("from mn(/E/
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" + entity.getName()); vNPfUEnA
} 4+-5,t7
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publicList findByNamedQuery(finalString y9=t;qH@|
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namedQuery){ o@Scz!"g
return getHibernateTemplate U.Pa7tn
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().findByNamedQuery(namedQuery); 7Y%!,ff
} 3L?WTS6(u
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publicList findByNamedQuery(finalString query, '_k >*trV
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finalObject parameter){ hcd!A5
return getHibernateTemplate <zfO1~^
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().findByNamedQuery(query, parameter); /]pX8
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} _RN/7\
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publicList findByNamedQuery(finalString query, jG
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finalObject[] parameters){ X77A; US
return getHibernateTemplate jM6uT'Io
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().findByNamedQuery(query, parameters); 0Ddn@!J*
} u4go*#
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publicList find(finalString query){ ]lymY _ >
return getHibernateTemplate().find &uv>'S#%
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(query); %j~9O~-
} .@4Q kG/
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publicList find(finalString query, finalObject 9"m,p
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parameter){ xAR^
return getHibernateTemplate().find #&;m<%
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(query, parameter); OJnPP>
} [6Uud iw
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public PaginationSupport findPageByCriteria _K
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(final DetachedCriteria detachedCriteria){ /&~nM
return findPageByCriteria 71K\.[ =-
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); HY*l 4QK
} k/$Ja;
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public PaginationSupport findPageByCriteria bx+(.F
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(final DetachedCriteria detachedCriteria, finalint {Bav$kw;?e
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startIndex){ J`U$b+q6
return findPageByCriteria =g{_^^n
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(detachedCriteria, PaginationSupport.PAGESIZE, :6\-9m8JM
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startIndex); O JZ!|J8?
} pkrl@jv >
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public PaginationSupport findPageByCriteria !Ei Ze.K
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(final DetachedCriteria detachedCriteria, finalint O^QR;<t'
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pageSize, 9+WY@du+
finalint startIndex){ *Y|lO
return(PaginationSupport) 34&u]4=L)
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getHibernateTemplate().execute(new HibernateCallback(){ *!-}lc^4
publicObject doInHibernate fJSV)\e0
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(Session session)throws HibernateException { ?^e*UJNM
Criteria criteria = e
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detachedCriteria.getExecutableCriteria(session); 7)ES!C
int totalCount = :X1`wBu
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((Integer) criteria.setProjection(Projections.rowCount mI{CM:
:
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()).uniqueResult()).intValue(); Zq2H9^![y~
criteria.setProjection g7E`;&f
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(null);
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List items = E-*>f"<h
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criteria.setFirstResult(startIndex).setMaxResults 1Ud
t9$~T
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(pageSize).list(); f_z2#,g
PaginationSupport ps = >X@.f1/5X
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new PaginationSupport(items, totalCount, pageSize, QjW~6Z.tI
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startIndex); M8^ziZY
return ps; S[\cT:{OE
} 8ESkG
}, true); _BeX7
} jS5t?0
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public List findAllByCriteria(final ;I0yQlx|U
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DetachedCriteria detachedCriteria){ RN cI]oJ
return(List) getHibernateTemplate N@%xLJF=N>
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().execute(new HibernateCallback(){ Yp?a=R
publicObject doInHibernate qqO10~Xc
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(Session session)throws HibernateException { x r+E
Criteria criteria = A7I8Z6&
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detachedCriteria.getExecutableCriteria(session); U3VsMV*Y
return criteria.list(); j3V"d 3)
} R[ +]d|L
}, true); MOH,'@&6^
} do:RPZ!
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public int getCountByCriteria(final <try%p|f
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DetachedCriteria detachedCriteria){ ni 02N3R
Integer count = (Integer) lzQ&)7`
f R{WS:Pv
getHibernateTemplate().execute(new HibernateCallback(){ ":ws~Zep
publicObject doInHibernate =^".{h'-
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(Session session)throws HibernateException { m-pIFL<^N
Criteria criteria = H~1?MAX
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detachedCriteria.getExecutableCriteria(session); 16d{IGMz
return JqH.QnKcv
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criteria.setProjection(Projections.rowCount Hf E;$
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()).uniqueResult(); Ov{B-zCA
} y|2g"J
}, true); vr]dRStr
return count.intValue(); :L+zUlsf
} $(<*pU
} -^SD6l$
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用户在web层构造查询条件detachedCriteria,和可选的 BfO}4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )="g?E3
gs2&0rnOy\
PaginationSupport的实例ps。 &`9bGO
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ps.getItems()得到已分页好的结果集 nh_xbo5L[
ps.getIndexes()得到分页索引的数组 70 DQ/b
ps.getTotalCount()得到总结果数 j(2tbWg9-
ps.getStartIndex()当前分页索引 oU{-B$w
ps.getNextIndex()下一页索引 8i+jFSZ$
ps.getPreviousIndex()上一页索引 C ^ k3* N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r|sy_Sk/{
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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 ,jdKcWy'
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一下代码重构了。 s!zr>N"
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我把原本我的做法也提供出来供大家讨论吧: _KlPbyLU
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首先,为了实现分页查询,我封装了一个Page类: ieK'<%dxF
java代码: ]&%X(jWyn
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/*Created on 2005-4-14*/ _[6+FdS],
package org.flyware.util.page; FV<^q|K/(]
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/** 1</t #r
* @author Joa Zi '8~iEH
* P<w>1
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*/ E9NGdp&-Ah
publicclass Page { mm~o%1|WR
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/** imply if the page has previous page */ |x~ei_x7.p
privateboolean hasPrePage; @;-Un/'C;7
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/** imply if the page has next page */ >Sl:Z ,g;
privateboolean hasNextPage; Sv[_BP\^h
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/** the number of every page */ Op)R3qt{
privateint everyPage; o3`gx
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/** the total page number */ (:hmp"S
privateint totalPage; KLM^O$=
I2!&=" 7@
/** the number of current page */ pPqbD}p
privateint currentPage; hB1 iSm
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/** the begin index of the records by the current "Kf~`0P
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query */ s#CEhb
privateint beginIndex; !haXO
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/** The default constructor */ 5+PBS)pJ]%
public Page(){ (3HgI
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} ~V)VGGOL$v
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/** construct the page by everyPage +(hwe
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* @param everyPage sjbC~Te--
* */ eT
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public Page(int everyPage){ olW`.3f
this.everyPage = everyPage; #hiDZ>nr
} %y~]3XWik
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/** The whole constructor */ 0hr)tYW,G
public Page(boolean hasPrePage, boolean hasNextPage, LGue=Hkp
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int everyPage, int totalPage, |Szr=[
int currentPage, int beginIndex){ ~.=HN}E
this.hasPrePage = hasPrePage; s~'C'B?
this.hasNextPage = hasNextPage; X_yU"U
this.everyPage = everyPage; c35vjYQx0
this.totalPage = totalPage; <Gt{(is
this.currentPage = currentPage; |L#r)$n{1
this.beginIndex = beginIndex; 6aK2{-+
} tWy<9TF
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/** [WSIC *|;
* @return X "r$,~
* Returns the beginIndex. ?d'9TOlD
*/ o*S $j Cf?
publicint getBeginIndex(){ X Ow^"=Oa[
return beginIndex; MPw7!G(qj
} zb*4Nsda:
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/** n ]g,)m
* @param beginIndex i2c<q0u
* The beginIndex to set. 8?R_O}U
*/ \r&@3a.>
publicvoid setBeginIndex(int beginIndex){ n Fn`>kQ
this.beginIndex = beginIndex; g#&##f
} {N`<e>A]{
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/** 69w"$Vk
* @return [wxI
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* Returns the currentPage. Oc=PJf%D#
*/ L*Cf&c`8r
publicint getCurrentPage(){ qf {B
return currentPage; Z-V%lRQ=b
} LR.+CxQ
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/** -C]a2
* @param currentPage ~#Mx&mZ
* The currentPage to set. U~c;W@T
*/ xL"o)]a=
publicvoid setCurrentPage(int currentPage){ nlnJJM&J$
this.currentPage = currentPage; M- A}(r +J
} hS/'b$#
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/** $S ("-3
* @return =f|a?j,f~
* Returns the everyPage. <;"=ah7A
*/ cC]1D*Bn
publicint getEveryPage(){ CR=MjmH
return everyPage; %P6!vx:&^b
} N*-Z Jv
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/** HK.J/Zr
* @param everyPage H!=BjU1Pmg
* The everyPage to set. bME3" e{O
*/ w#b2iE+Bw
publicvoid setEveryPage(int everyPage){ md
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this.everyPage = everyPage; `v
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} 9D21e(7X
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/** gWPa8q<b
* @return ' qVa/GJ
* Returns the hasNextPage. uwzT? C A6
*/ e8v=n@0
publicboolean getHasNextPage(){ p$<qT^]&
return hasNextPage; a^,RbV/
} }A^,y
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/** |0mI3r
* @param hasNextPage _J!mhUA
* The hasNextPage to set. (iP,YKG1?
*/ &9{BuBO[
publicvoid setHasNextPage(boolean hasNextPage){ ,:{+
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this.hasNextPage = hasNextPage; EC/R|\d?Un
} xnOlV
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/** 9m!fW|4
* @return B/}>UHM
* Returns the hasPrePage. 9\2&6H
*/ JH#?}L/0Fe
publicboolean getHasPrePage(){ !}7m^
return hasPrePage; lY`<-`{I_
} j+/*NM_y3
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/** S\(_"xJPp
* @param hasPrePage N|}`p"
* The hasPrePage to set. aoS1Yt'@
*/ r0>T7yPAK
publicvoid setHasPrePage(boolean hasPrePage){ RJD3o_("K
this.hasPrePage = hasPrePage; 7a net
} E
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}XU- JAn
/** UJ:B:hh''
* @return Returns the totalPage. 8EA?'~"
* IgL8u
*/ *Y~64FM
publicint getTotalPage(){ Po3W+;@
return totalPage; f_8~b0`
} jEI L(0_H
yW 3h_08
/** @dNbL}qQ
* @param totalPage <5%We(3
* The totalPage to set. Q{60^vg
*/ 7j8_O@_
publicvoid setTotalPage(int totalPage){ ;q2T*4NN
this.totalPage = totalPage; 6~LpBlb
} Ok!{2$P8U9
&@+;]t
} rv:O|wZ
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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 QTH yH
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个PageUtil,负责对Page对象进行构造: Pl4d(2
7
java代码: ;nE}%lT
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/*Created on 2005-4-14*/ |1o]d$3m
package org.flyware.util.page;
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import org.apache.commons.logging.Log; c/RG1w
import org.apache.commons.logging.LogFactory; LJD"N#c
Y|F);XXIl
/** rH,N.H#]
* @author Joa , utFCZW
* 4p.O<f;A8
*/ tN~{Mt$-W
publicclass PageUtil { _[W=1bGJ
:nI.Qa'"H
privatestaticfinal Log logger = LogFactory.getLog )<d8y Lb
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(PageUtil.class); K9R[
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bu-
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/** .@'Vz;&mQ
* Use the origin page to create a new page 5|Qr"c$p
* @param page xlAaIo)T
* @param totalRecords `F#KXk
* @return H@zpw1fH+
*/ ?9:\1)]
publicstatic Page createPage(Page page, int ?jbam!A
W2RS G~|
totalRecords){ 43Q&<r$[T
return createPage(page.getEveryPage(), Hg4Ut/0
@)B_e*6>'
page.getCurrentPage(), totalRecords); Z5Cv$bUc
} W3b\LnUa
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/** [>E0(S]
* the basic page utils not including exception `*]r.u0
_~!,x.Dbp
handler 7Do)++t
* @param everyPage \MU4"sXw
* @param currentPage PA E)3
* @param totalRecords L<:ya
* @return page dx^3(#B
*/ yAOC<d9 E
publicstatic Page createPage(int everyPage, int [LCi,
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currentPage, int totalRecords){ kHO\#fF<
everyPage = getEveryPage(everyPage); IX}l)t[:(
currentPage = getCurrentPage(currentPage); 08Q:1 '
int beginIndex = getBeginIndex(everyPage, -?uwlpm#
0*q:p`OLw*
currentPage); eMs`t)rQ
int totalPage = getTotalPage(everyPage, sb1/4u/W
`f s[C
totalRecords); vI-KH:r"{
boolean hasNextPage = hasNextPage(currentPage, MmX42;Pw
q~qig,$Y
totalPage); $jHL8r\e7
boolean hasPrePage = hasPrePage(currentPage); SNQ+ XtoO
m ]\L1&
returnnew Page(hasPrePage, hasNextPage, &+\wYa,
everyPage, totalPage, ;(XSw%Y
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currentPage, xsfq[}eH<
, Le_PJY)
beginIndex); E$cr3 t7Xy
} -$7Jc=:>
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privatestaticint getEveryPage(int everyPage){ \sk,3b-&'
return everyPage == 0 ? 10 : everyPage; [-l^,,E
} Uc4r
J(Bn
n
privatestaticint getCurrentPage(int currentPage){ ~Sh}\&3p
return currentPage == 0 ? 1 : currentPage; '@$?A>.cj
} \R~Lf+q
dgO2fI
privatestaticint getBeginIndex(int everyPage, int >@t]M`#&h
3yTBkFI!
currentPage){ :7R\"@V4
return(currentPage - 1) * everyPage; E( TY%wO
} U}UIbJD*=
? f%@8%px
privatestaticint getTotalPage(int everyPage, int (k[<>$hL*
eN/Jb;W
totalRecords){ @-hy:th#
int totalPage = 0; h.67]U7m
4EOu)#
if(totalRecords % everyPage == 0) k2xjcrg
totalPage = totalRecords / everyPage; 69_c,(M0
else `q F:rQ
totalPage = totalRecords / everyPage + 1 ; lU\|F5O@#
qB8<(vBP+
return totalPage; dZZHk
} QPBf++|
+'[iyHBJ
privatestaticboolean hasPrePage(int currentPage){ 3mx7[Q
return currentPage == 1 ? false : true; blLX ncyD
} ztu N0}'
[\I\).
privatestaticboolean hasNextPage(int currentPage, P|G:h&
n|(Y?`(
int totalPage){ z8gp<5=
return currentPage == totalPage || totalPage == n.XT-X^
-q-%)f
0 ? false : true; _N<8!(|w
} Z
rvb
%
P/^:IfuR
OrzDr
} r>
NgJf,
0n5N-b?G-@
`AYHCn
T'w=v-(J
oqG
0 @@
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。 <}|+2f233+
Rrs z{a
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 v=|ahsYC
r l!c\
做法如下: `DEz `
D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 3xeW!~
zV%U4P)Dao
的信息,和一个结果集List: _m;Y'
java代码: M*%iMz
63ht|$G
RsY|V|<
/*Created on 2005-6-13*/ y%43w4
package com.adt.bo; ,;UVQwY
Qp{{OjD
import java.util.List; ~~>D=~B0'
>YD?
pDPb/
import org.flyware.util.page.Page; "MlY G6
i/~A7\:8%
/** x#'#
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* @author Joa uQrD}%GI
*/ P.LMu
publicclass Result { nd-y`@z
%|4Nmf$:Og
private Page page; ?FD^S~bz-
]Rz]"JZ\S
private List content; $dq
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]>&au8
/** Rs7=v2>I
* The default constructor GBN^ *I
*/ ~fEgrF d
public Result(){ 2}t2k>
super(); TN(1oJ:
} W,}C*8{+
*uNa(yd
/** nT9B?P>
* The constructor using fields YS%HZFY, "
* _r&`[@m
* @param page m%l\EE
* @param content ,{7Z OzA
*/ B_nim[72
public Result(Page page, List content){ | M4_@P
this.page = page; 9>%ti&_-jt
this.content = content; JuS#p5E #
} u1(`^^Ml
y?;&(Tcbt8
/** zJOL\J'
* @return Returns the content. f8!*4Bw
*/ b<NI6z8\
publicList getContent(){ t*~V]wZ
return content; Fep#Pw1
} YqrieDFay!
3Jf_3c
/** d A[I
* @return Returns the page. hgL wxJu
*/ V!(Ty%7
public Page getPage(){ <Zl}u:(w
return page; >d&B:
} N!{('po
gYw4YP0Gz
/** FTsvPLIv"
* @param content :[?hU}9
* The content to set. a)/!ifJ;
*/ d@JjqE[
public void setContent(List content){ FQ26(.
this.content = content; a^>0XXr}Y
} TDq(%IW
a"4j9cO
/** .k|8nNj
* @param page ?zM]p"M
* The page to set. xp.~i*!`
*/ 3{O^q/R
publicvoid setPage(Page page){ FIDV5Y/f
this.page = page; >$j?2,Za(V
} ^9UKsy/q
} HM/2/
/
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>hQeu1 ~W
S=@.<gS
y yW;VKN
2. 编写业务逻辑接口,并实现它(UserManager, 9(V12gn+lk
}4b
4<Sm_h
UserManagerImpl) a6cq0g[# z
java代码: aSkH<5i`v
uS`XWn<CSD
#(=8
RA:@
/*Created on 2005-7-15*/ g4EC[>5!r
package com.adt.service; $F"'=+0
Qyx%:PE
import net.sf.hibernate.HibernateException; =dSH8C"
s]@()?.E$
import org.flyware.util.page.Page; b"DaLwKkz
Zn0e#n
import com.adt.bo.Result; F !g>fIg
o'O;69D]tX
/** 7&;M"?m&
* @author Joa Wa7-N4
*/ DybuLB$f
publicinterface UserManager { +}[M&D
sxkWg>
public Result listUser(Page page)throws ?Dm={S6
4+I @
HibernateException; ammlUWl
w+($=n~
} 0N>NX?r
0h=NbLr|S-
0}H7Xdkp
c&me=WD
z-ns@y(f@X
java代码: &m[ZpJ9
^,O%E;g^#
+?y ', Ir
/*Created on 2005-7-15*/ = Lt)15
package com.adt.service.impl; bl yU53g
0P i+ (X
import java.util.List; [}:;B$,
pZHx
import net.sf.hibernate.HibernateException; >J(._K
F#Y9 @E
import org.flyware.util.page.Page; )S"!)\4 b
import org.flyware.util.page.PageUtil; GWd71ZtFO
5,dKha
import com.adt.bo.Result; I8};t b#
import com.adt.dao.UserDAO; I(m*%>
import com.adt.exception.ObjectNotFoundException; R `K1L!`3
import com.adt.service.UserManager; x9\z^GU%H
eLF xGZ Z
/** u|(;SY
* @author Joa !r^fX=X>'
*/ [~_)]"pU
publicclass UserManagerImpl implements UserManager { .Nk'yow
4Ys\<\~d
private UserDAO userDAO; (-S\%,hO
ak1?MKV.
/** |Yb]@9>vn
* @param userDAO The userDAO to set. zu/BDyF
*/ cPunMHD
publicvoid setUserDAO(UserDAO userDAO){ qh9d.Q+n
this.userDAO = userDAO; ;Qn)~b~
} Q rBb!.r
L;RHshTy
/* (non-Javadoc) gpT~3c;l=
* @see com.adt.service.UserManager#listUser Z=R 6?jU*n
wCQ.?*7-9Q
(org.flyware.util.page.Page) At<D36,^"
*/ ~dXiyU,y2
public Result listUser(Page page)throws ;*(i}'
(>49SOu;$\
HibernateException, ObjectNotFoundException { ~}"5KX\=#
int totalRecords = userDAO.getUserCount(); g79zzi-
if(totalRecords == 0) wF=?EK(;P{
throw new ObjectNotFoundException @tT2o@2Y^
f?JP=j
("userNotExist"); ?kM2/a"{G
page = PageUtil.createPage(page, totalRecords); 5nV IC3N+1
List users = userDAO.getUserByPage(page); M:M"7>:
returnnew Result(page, users); &c[ISc>N{
} Uv) B
PPAcEXsIu
} mP*Ct6628n
NI
r"i2
(zr2b
=0t<:-?.-
:%[mc-6.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /6y9u}
Y~TD)c=
询,接下来编写UserDAO的代码: '2z1$zst,#
3. UserDAO 和 UserDAOImpl: ^V}c8 P|
java代码: ]A=yj@o$xN
Y;)l
P+L#p(K
/*Created on 2005-7-15*/ :X*$U
~aQ
package com.adt.dao; S:lie*Aux*
eC{St0
import java.util.List; gWD46+A){
AXpg_JC
import org.flyware.util.page.Page; .QU]
x?7z15\
import net.sf.hibernate.HibernateException; 4^Ke?;v
C;3
/** mWUkkR(/
* @author Joa prEI9/d"
*/ ;,lFocGv
publicinterface UserDAO extends BaseDAO { Y{d-k1?s5
"l 8YD&q
publicList getUserByName(String name)throws w2H^q3*
"IHFme@^
HibernateException; H-,p.$3}
y[{}124
publicint getUserCount()throws HibernateException; ~2;\)/E\
Na>w~
publicList getUserByPage(Page page)throws !aB~G}'
B ({g|}|G+
HibernateException; HDO_r(i
<KX fh
} }U'VVPh_
OF} ."a
%At.nlss
RkZyqt
@+
cJE4uL<
java代码: %p:Z(zU
z3c7
Ot+Z}Z-
/*Created on 2005-7-15*/ )DGJr/)
package com.adt.dao.impl; mclV"?
~8&P*oFC
import java.util.List; GdYQq.
MTip4L W9
import org.flyware.util.page.Page; cT5BBR
p\P)
import net.sf.hibernate.HibernateException; =w!2R QB
import net.sf.hibernate.Query; Q?V+
0J
*/HW]x|?V~
import com.adt.dao.UserDAO; GG`j9"t4
8<x&
Xd
/** R=<%!
* @author Joa sXmP<c
*/ @'A0Lq+#
public class UserDAOImpl extends BaseDAOHibernateImpl F/PH=Dk
T/FZn{I
implements UserDAO { T>pyYF1Q
U.WXh(`%
/* (non-Javadoc) /}/GK|tj
* @see com.adt.dao.UserDAO#getUserByName BNgm+1?L
F`La_]f?b\
(java.lang.String) \.'[!GE *c
*/ 1Va=.#<
publicList getUserByName(String name)throws F9"Xu-g
b<%c ]z
HibernateException { Wecxx^vtv6
String querySentence = "FROM user in class S5kD|kJ
lMl'+ yy
com.adt.po.User WHERE user.name=:name"; zGdYk-H3TH
Query query = getSession().createQuery /'/i?9:
4jc?9(y%
(querySentence); vjzG
H*
query.setParameter("name", name); 5 B t~tt
return query.list(); $<9u:.9xf
} AhkDLm+
yD Jy'Z_F{
/* (non-Javadoc) T^F83Py<
* @see com.adt.dao.UserDAO#getUserCount() S['cX ~
*/ ol K+|nR
publicint getUserCount()throws HibernateException { +|x{?%.O
int count = 0; G`;\"9t5h
String querySentence = "SELECT count(*) FROM m[z$y
c39j|/!;Y
user in class com.adt.po.User"; B<ncOe
Query query = getSession().createQuery :`4F0
a`8]TD
(querySentence); &Yo|Pj
count = ((Integer)query.iterate().next S.{
yh/JHo;
()).intValue(); UM`{V5NG#
return count; *$5p,m6G
} /+*N.D'`t,
r\cY R}v
/* (non-Javadoc) 9Z }<H/q
* @see com.adt.dao.UserDAO#getUserByPage t(dVd%
/OYa1,
(org.flyware.util.page.Page) %NfXe[T
*/ 3 yw$<lm
publicList getUserByPage(Page page)throws CiGXyhh
MsBm0r`a
HibernateException { LuHRB}W
String querySentence = "FROM user in class ~o/k?l
SQhVdYU1'
com.adt.po.User"; 7r50y>
Query query = getSession().createQuery Aix6O=K6
:<mJRsDf
(querySentence); F+GX{e7E\
query.setFirstResult(page.getBeginIndex()) /G|v.#2/g
.setMaxResults(page.getEveryPage()); )[J@s=
return query.list(); )iM(
\=1ff
} }6BXa
IuT)?S7O*k
} ;c>"gW8
.k-6LR
z9g ++]rkJ
U[|5:qWs
3tCTPZy
至此,一个完整的分页程序完成。前台的只需要调用 tjwnFqI
D(;+my2
userManager.listUser(page)即可得到一个Page对象和结果集对象 C
#iZAR
2Wu`Dp;&l
的综合体,而传入的参数page对象则可以由前台传入,如果用 [\#ANA"
sQj]#/yK:
webwork,甚至可以直接在配置文件中指定。 y/ Bo4fM
<ch}]-_
下面给出一个webwork调用示例: N$=9R
java代码: 39hep8+
^N[ Cip}8
t$%<eF@w
/*Created on 2005-6-17*/ }^0'IAXi
package com.adt.action.user; 8'L:D
|!9xL*A
import java.util.List; bS2g4]$'po
{lH'T1^m
import org.apache.commons.logging.Log; ?O+.
import org.apache.commons.logging.LogFactory; &6C]|13;
import org.flyware.util.page.Page; V8):!
2J{vfF
import com.adt.bo.Result; )c&ya|h
import com.adt.service.UserService; 6)ibXbH
import com.opensymphony.xwork.Action; 6u #eLs
Y.) QNTh
/** d,N6~?B
* @author Joa -(F}=o'
*/ B1J,4
publicclass ListUser implementsAction{ yf0v,]v[
u6F>o+Td)
privatestaticfinal Log logger = LogFactory.getLog as]M%|/-I
Im\ ~x~{
(ListUser.class); z,$uIv}'@
S6(48/
private UserService userService; @--"u_[
|'1.ajxw
private Page page; v@ OELJX
7Y[ q)lv
privateList users; C4$P#DZT^
B*mZxY1
/* Ahl&2f\
* (non-Javadoc) Qw5(5W[L
* O|+ZEBP
* @see com.opensymphony.xwork.Action#execute() :e=7=|@7
*/ =oIt.`rf
publicString execute()throwsException{ ?g{[U0)
Result result = userService.listUser(page); T)sIV5bk
page = result.getPage(); yNXYS
users = result.getContent(); y>x"/jzF#
return SUCCESS; iAQ[;M3p
} y705
2w3LK2`ZL
/** i
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* @return Returns the page. C5-u86F
*/ >oWPwXA
public Page getPage(){ 8^+|I,
return page; H390<`
} ]o]`X$n
e-P{)L<s5
/** 2<5LQr
* @return Returns the users. G gA:;f46
*/ X!LiekU!D
publicList getUsers(){ WN{8gL&y
return users; ^8~TsK~
} PdVx&BL*
?i0+h7=6
/** DJgM>&Y6,
* @param page `Wjq$*
* The page to set. C(v'7H{4cW
*/ #K:iB*
publicvoid setPage(Page page){ 1="]'!2Is
this.page = page; Qc-W2%
} g2TK(S|#
Uz,P^\8^$
/** Jj[3rt?8
* @param users Mn/
* The users to set. gizY4~
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*/ 1}|y^oB\-
publicvoid setUsers(List users){ ,"`3N2!Y}
this.users = users; \mGb|aF8
} *\xRNgEQ
]~dB|WB
/** ,&4
[`d
* @param userService xj U0&
* The userService to set. hz;SDaBA
*/ Od;k}u6;<
publicvoid setUserService(UserService userService){ @w= =*.x
this.userService = userService; *(q{k%/M
} 5OGwOZAj52
} fgtwVji
!gRU;ZQU_
0 fT*O
y~#5!:Be
rwUhNth-Qh
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, ^0>^5l'n
T+P{,,a/]
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 ,/Gp>Yqx
A@lM=
么只需要: jWxa
[>
java代码: 7mi*#X}
?^!J:D?
U= n
<?xml version="1.0"?> Q$.CtECo
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 8M!9gvcaO
$<Gt^3e
1.0//EN" "http://www.opensymphony.com/xwork/xwork- EB+4]MsD
u"v$[8
1.0.dtd"> "[["naa
'!Va9m*w7
<xwork> B
&Z0ZWx
=r]_$r%gR
<package name="user" extends="webwork- !K*3bY`#
:jTbzDqQ
interceptors"> 2ALYfZ|d
d:&cq8^
<!-- The default interceptor stack name AX@bM
\ :@!rM
--> 0W6='7
<default-interceptor-ref (0 t{
Dy. |bUB!f
name="myDefaultWebStack"/> E"BW-<_!
S?v;+3TG
<action name="listUser" \J(~
Nv5!
nSo.,72
class="com.adt.action.user.ListUser"> "0G)S'
<param r
H9}VA:h
T^|6{ S\
name="page.everyPage">10</param> iuEe#B;!
<result PB8U+
E(S$Q^
name="success">/user/user_list.jsp</result> :Oj!J&A
</action> Us&~d"n
vy5{Vm".4
</package> 'g)5vI~'
TffeCaBv
</xwork> #CeWk$)m
Pvkr$ou
m7>)p]]
78Zb IL
V^G+_#@,,
uX7"u*@Q*~
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 )buy2#8UW
[F *hjGLc}
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。 %tkL<e
gY-}!9kW]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 JKYl
q4/P'.S
Hn)^C{RN*{
fk5pPm|MiL
x?R1/iHv
我写的一个用于分页的类,用了泛型了,hoho 2F1Bz<
,`ehR6b
java代码: QA!'p1{#
M|z4Dy
.0y .0=l
package com.intokr.util; x*^)B~7}
1G, '
import java.util.List; A sf]sU..
kafj?F
/** c&L|e$C]
* 用于分页的类<br> >?X(,c
* 可以用于传递查询的结果也可以用于传送查询的参数<br> F JxH{N6a
* .ddf'$6h
* @version 0.01 z{>
)'A/
* @author cheng <e8Ux#x/
*/ =p!Hl#
public class Paginator<E> { $kQQdF
privateint count = 0; // 总记录数 8`w#)6(V
privateint p = 1; // 页编号 l=&Va+K
privateint num = 20; // 每页的记录数 1NlpOVq:)
privateList<E> results = null; // 结果 ^''3}<Ep
60p*4>^v
/** zZCssn;[
* 结果总数 ?O
e,
*/ t+WUz#i"
publicint getCount(){ XlxB%
return count; QfU{W@!h
} Kv\uBMJNW
P<xCg
publicvoid setCount(int count){ /(ArA=#
this.count = count; Q;p%
VQ
} Q
S.w#"X[
Z2\Xe~{
/** 4L6'4 t"s
* 本结果所在的页码,从1开始 9fqCE619a
* z"@UNypc,
* @return Returns the pageNo. 8nRxx`U\q
*/ r?n3v[B
publicint getP(){ *3Ci4\Ew
return p; @z.HyQ_v
}
A,|lDsvM
,#=;V"~9
/** 2`/p V0
* if(p<=0) p=1 EtvYIfemr
* ^pa -2Ao6
* @param p K06&.>v_
*/ Q|HOy8O}Z
publicvoid setP(int p){ &f>1/"lnd\
if(p <= 0) _/[(&}M
p = 1; w8AHs/'r
this.p = p; F1zsGlObu}
} e~BUAz
8 =<&9TmE
/** Y)v_O_`
* 每页记录数量 Wp$'#HhB
*/ 3HmJixy
publicint getNum(){ SE!0f&
return num; *e-+~/9~
} VbzW4J_
Jyu*{
/** {[.<BU-
* if(num<1) num=1 wS1zd?
*/ ]^CNC0
publicvoid setNum(int num){ )h?Pz1-W1
if(num < 1) ?qjlWCV|e
num = 1; !+I!J
s"
this.num = num; P"mD73a
} (
u}tUv3
tqe8:\1yK
/** a)Ca:p
* 获得总页数 B mxBbg
*/ APu cA
publicint getPageNum(){ yY42+%P
return(count - 1) / num + 1; |nj,]pA
} b6UD!tXp
jPNm $Y1
/** 4 '6HX#J
* 获得本页的开始编号,为 (p-1)*num+1 U
ORoj )$I
*/ [P23.`G~J
publicint getStart(){ <O?UC/$)7
return(p - 1) * num + 1; H-.8{8
} 4#y
:vJ0Ypz-u
/** (>Tq
* @return Returns the results. g!`$bF=e
*/ P 6|\
^
publicList<E> getResults(){ ENi@R\
p
return results; &ahZ_9Q
} ${F]N }
/!Ng"^.e
public void setResults(List<E> results){ %7~~*_G
this.results = results; H#;-(`F
} 1tQl^>r16
?N*|S)BN
public String toString(){ r8E)GBH-|
StringBuilder buff = new StringBuilder /Z*XKIU6v/
g4 |s9RMD
(); JH;\wfrD
buff.append("{"); 6-<>P E2
buff.append("count:").append(count); 36U
zfBa
buff.append(",p:").append(p); ?R}a,k
buff.append(",nump:").append(num); gjVKk
buff.append(",results:").append )N4_SA
$NtbI:e{
(results); _ *O^|QbM
buff.append("}"); +5+?)8Ls
return buff.toString(); n^AQ!wC
} 2& l~8,
hs"=>(P)
} "NamP\hj
hkq[xgX
Y&Sk/8