Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _?q\tyf3
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T'Jw\u>"R
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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 f_raICO{R
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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 #B+2qD>E
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分页支持类: +hXph
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java代码: ;PS[VdV
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package com.javaeye.common.util; 83TN6gW
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import java.util.List; 1L l@
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publicclass PaginationSupport { TC R(
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publicfinalstaticint PAGESIZE = 30; 3j.f3~"
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privateint pageSize = PAGESIZE; t}'Oh}CG
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privateList items; BT#'<!7!
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privateint totalCount; aNXu"US+Sp
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privateint[] indexes = newint[0]; /3+7a\|mKr
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privateint startIndex = 0; FirmzB Il5
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public PaginationSupport(List items, int \W1?Qc1]
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totalCount){ r ."Dc
setPageSize(PAGESIZE); ;TaT=%
setTotalCount(totalCount); 1Z`<HW"
setItems(items); &p4q# p7,
setStartIndex(0); iY*Xm,#
} *;o=hM)Tp
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public PaginationSupport(List items, int Sf*VkH
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totalCount, int startIndex){ J@yy2AZnO
setPageSize(PAGESIZE); o'D6lkf0
setTotalCount(totalCount); zo]7#
setItems(items); X8*q[@$
setStartIndex(startIndex); a(BC(^1!
} "$Rl9(}
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public PaginationSupport(List items, int tnKzg21%
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totalCount, int pageSize, int startIndex){ ^M?uv{354
setPageSize(pageSize); ZC0F:=/K
setTotalCount(totalCount); }-8K*A3
setItems(items); nGyY`wt&Rg
setStartIndex(startIndex); @rVmr{UE
} }b,a*4pN
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publicList getItems(){ 0>.'w\,87B
return items; h!)(R<
} $RF"m"
,
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publicvoid setItems(List items){ mXa1SZnE
this.items = items; St&XG>nWS
} gw5CU)r4$
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publicint getPageSize(){ (S(=W G
return pageSize; wePMBL1P*
} B;rq{ac!P]
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publicvoid setPageSize(int pageSize){ T mUn/
this.pageSize = pageSize; Y3-15:-
} X|.X4fs
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publicint getTotalCount(){ I:Z38xz -[
return totalCount; ,sJ{2,]~
} 1zl@$ Nt
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publicvoid setTotalCount(int totalCount){ U>:p`@
if(totalCount > 0){ LTJ|EXYA
this.totalCount = totalCount; 9^jO^[>
int count = totalCount / 9N-mIGJ
3 #jPQ[+
pageSize; 4\-kzGgmo
if(totalCount % pageSize > 0) i>0bI^H
count++; u/hD9g~H7K
indexes = newint[count]; Be}Cj(C
for(int i = 0; i < count; i++){ /S|Pq!4<
indexes = pageSize * _u.l|yR
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} >\VZ9bP<
}else{ /~AajLxu3W
this.totalCount = 0; ~IlgcCF
} R=PjLH&)
} m2\ZnC
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publicint[] getIndexes(){ F1MPo;e
return indexes; (\SxG\`
} h`jtmhoz
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publicvoid setIndexes(int[] indexes){ 5)EnOT"'
this.indexes = indexes; Dwwh;B
} iiO4.@nT
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publicint getStartIndex(){ $L;7SY?
return startIndex; u,/PJg-(!
} g3"`b)M
}X}fX#[
publicvoid setStartIndex(int startIndex){ =Ermh7,
if(totalCount <= 0) xNl_Q8Z?R^
this.startIndex = 0; %hOe `2#$
elseif(startIndex >= totalCount) 3<?(1kSo>>
this.startIndex = indexes ;Wb
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[indexes.length - 1]; |?{Zx&yUw
elseif(startIndex < 0) z)Bc91A
this.startIndex = 0; Qs</.PO
else{ +ZXk0sP_<
this.startIndex = indexes R%54!f0
%
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[startIndex / pageSize]; =j}]-!
} 3X%>xUI
} ,9
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publicint getNextIndex(){ >CNH=
int nextIndex = getStartIndex() + P(qUx9
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pageSize; /R@eOl}D
if(nextIndex >= totalCount) mWCY%o@
return getStartIndex(); E3sl"d;~
else *G2p;n=2
return nextIndex; YV 2T$#7u
} mI?AI7DqK
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publicint getPreviousIndex(){ _ jF,
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int previousIndex = getStartIndex() - jD'\\jAUdm
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pageSize; n$B=Vt,
if(previousIndex < 0) Lk=f^qJ
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return0; YG!~v~sV
else 1kvBQ1+
return previousIndex; lP\7=9rh^x
} gQ/-.1Pz$
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} U''/y\Z
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抽象业务类 b-yfBO
java代码: g]N!_Ib/!
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/** xW!2[.O5H
* Created on 2005-7-12 Rs8^ 27
*/ %9uLxC;
package com.javaeye.common.business; $wub)^
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import java.io.Serializable; &X
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import java.util.List; dzKI?i)x
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import org.hibernate.Criteria; CcG{+-=H)
import org.hibernate.HibernateException; AKzhal!
import org.hibernate.Session; *[9FPya
import org.hibernate.criterion.DetachedCriteria; =hjff/
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import org.hibernate.criterion.Projections; QcU&G*
import &k+jVymH
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org.springframework.orm.hibernate3.HibernateCallback; JS1$l+1
import h2QoBGL5
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org.springframework.orm.hibernate3.support.HibernateDaoS dmgoVF_qR
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upport; 9o@5:.b<j
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import com.javaeye.common.util.PaginationSupport; ?>92OuG%W?
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public abstract class AbstractManager extends vR[XbsNM
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HibernateDaoSupport { R7+3$F5B
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privateboolean cacheQueries = false; _lcx?IV
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privateString queryCacheRegion; omisfu_~E
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publicvoid setCacheQueries(boolean yr8
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cacheQueries){ (,*e\o
this.cacheQueries = cacheQueries; 7jPPN
} #fk#RNt
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publicvoid setQueryCacheRegion(String SM;UNIRVE
}#]2u|G
queryCacheRegion){ MKMWHGN
this.queryCacheRegion = XRARgWj
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queryCacheRegion; "jS@ug
} >|Yr14?7
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publicvoid save(finalObject entity){ ~U"puEftbs
getHibernateTemplate().save(entity); hilgl<UF
} onqfmQ,3E
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publicvoid persist(finalObject entity){ .xG3`YH
getHibernateTemplate().save(entity); '9@} =pE
} m
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publicvoid update(finalObject entity){ Ix~_.&
getHibernateTemplate().update(entity); /<zBjvr%%
} . l1uqCuB
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publicvoid delete(finalObject entity){ 8);G'7O
getHibernateTemplate().delete(entity); -(~OzRfYi
} P)D2PVD
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publicObject load(finalClass entity, $?`-} wY
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finalSerializable id){ f%ThS42
return getHibernateTemplate().load naOCa
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(entity, id);
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} >`{B
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publicObject get(finalClass entity, gdr"34%vbM
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finalSerializable id){ XWd;-%`<
return getHibernateTemplate().get FUTD/y]Lu
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(entity, id); t,P_&0X
} |J:|56kVZq
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publicList findAll(finalClass entity){ B
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return getHibernateTemplate().find("from Z.QgL=
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" + entity.getName()); (i 2R1HCa
} 7oWT6Qa5
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publicList findByNamedQuery(finalString C
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namedQuery){ 3bU(ea^e$
return getHibernateTemplate 'r0kX||
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().findByNamedQuery(namedQuery); nY)H-u^
} _ J t
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publicList findByNamedQuery(finalString query, mxPzB#t4
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finalObject parameter){ zhdS6Gk+
return getHibernateTemplate ;07>ZH%
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().findByNamedQuery(query, parameter); gJFx#s0?6.
} 7B@1[
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publicList findByNamedQuery(finalString query, t@vVE{`
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finalObject[] parameters){ ,
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return getHibernateTemplate yQz6K6p
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().findByNamedQuery(query, parameters); ud
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} rgw@
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publicList find(finalString query){ $o%:ST4
return getHibernateTemplate().find
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(query); 4`[2Te>
} )45#lE3TH
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publicList find(finalString query, finalObject ZJf:a}=h
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parameter){ [,0[\NC
return getHibernateTemplate().find 2
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(query, parameter); g-LMct8$
} I83 _x|$FZ
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public PaginationSupport findPageByCriteria HT%'dZ1
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(final DetachedCriteria detachedCriteria){ 90Bn}@t=Q
return findPageByCriteria evvv&$&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); up!54}qy
} A4{p(MS5
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public PaginationSupport findPageByCriteria ?1.WF}X'
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(final DetachedCriteria detachedCriteria, finalint JKTn
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startIndex){ )#l&BV5
return findPageByCriteria ~J![Nx/
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(detachedCriteria, PaginationSupport.PAGESIZE, 85:KlBe%+
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startIndex); z 4qEC
} -q30tO.
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public PaginationSupport findPageByCriteria ,4HZ-|EOZ
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(final DetachedCriteria detachedCriteria, finalint | Di7,$c
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pageSize, ?mHu eX
finalint startIndex){ %v4*$E!f
return(PaginationSupport) )kEH}P&
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getHibernateTemplate().execute(new HibernateCallback(){ Bn{i+8I
publicObject doInHibernate }R!t/8K
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(Session session)throws HibernateException { qVssw* GDB
Criteria criteria = FQ>y2n=<d
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detachedCriteria.getExecutableCriteria(session); K5HzA1^
int totalCount = '#a;n
u'T?e+=
((Integer) criteria.setProjection(Projections.rowCount NG8F'=<
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()).uniqueResult()).intValue(); UPy 4ST
criteria.setProjection wb>"'%
}wZsM[NDB
(null); hkOFPt&
List items = R|92T*h
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criteria.setFirstResult(startIndex).setMaxResults ,3
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(pageSize).list(); TBZhL
PaginationSupport ps = +2w<V0V_
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new PaginationSupport(items, totalCount, pageSize, ftz-l&5
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startIndex); \5-Dp9vG
return ps; #O{cplh,
} 7x]q>Y8T
}, true); ;9<?~S
} }USOWsLSt
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public List findAllByCriteria(final N2 t`
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DetachedCriteria detachedCriteria){ T 0qM"
return(List) getHibernateTemplate X|yVRQ?F`
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().execute(new HibernateCallback(){ _gEojuaN
publicObject doInHibernate 0+k..l
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(Session session)throws HibernateException { 7uf5w0]
Criteria criteria = T
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detachedCriteria.getExecutableCriteria(session); `dWnu3r;
return criteria.list(); E:-~SH}
} q VavP6I
}, true); e jR_3K^
} 3.9/mztS
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public int getCountByCriteria(final &-!$qUli
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DetachedCriteria detachedCriteria){ 1!yd(p=cL
Integer count = (Integer) )3O#T$h
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getHibernateTemplate().execute(new HibernateCallback(){ ysCK_
publicObject doInHibernate 0+[3>N y0
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(Session session)throws HibernateException { I_e7rE0`
Criteria criteria = \T!,Z;zK
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detachedCriteria.getExecutableCriteria(session); !E|R3eX_
return 2
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criteria.setProjection(Projections.rowCount &kn?=NW
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()).uniqueResult(); ';}:*nZ//_
} H= w6
}, true); Spu;
return count.intValue(); K:% MhH-
} \t`Vq JLyu
} atW^^4:
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用户在web层构造查询条件detachedCriteria,和可选的 $at\aJ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ^uphpABpD
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PaginationSupport的实例ps。 s&+`>
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ps.getItems()得到已分页好的结果集 E2z=U
ps.getIndexes()得到分页索引的数组 t:P7ah
ps.getTotalCount()得到总结果数 1f1D^|
ps.getStartIndex()当前分页索引 Bn%?{z)
ps.getNextIndex()下一页索引 c<~DYe;;
ps.getPreviousIndex()上一页索引 lxbC 7?O
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 N)a5~<fBG
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ~IPATG
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一下代码重构了。 g;OR{
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我把原本我的做法也提供出来供大家讨论吧: *b!.9p K
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首先,为了实现分页查询,我封装了一个Page类: 44w
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java代码: <g\:By^
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/*Created on 2005-4-14*/ <Wj/A/
package org.flyware.util.page; cVarvueS
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/**
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* @author Joa UF\k0oLz
* :/Z1$xS
*/ Q,tjODc6n
publicclass Page { F9(jx#J~t
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/** imply if the page has previous page */ 0R0_UvsXU
privateboolean hasPrePage;
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/** imply if the page has next page */ J-G)mvkv
privateboolean hasNextPage; (JE&1 @
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/** the number of every page */ gdh|X[d
privateint everyPage; (y\.uPu!
. S;o#Zw*R
/** the total page number */ vS:=%@c>ta
privateint totalPage; '%rn-|)
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/** the number of current page */ P.=Dd"La
privateint currentPage; W>,D$
sebuuL.l0<
/** the begin index of the records by the current 5nmE*(
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query */ Fa </
privateint beginIndex; p^p1{%=
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/** The default constructor */ 0&Iu+hv
public Page(){ mM+^v[=
/nt%VLms%
} "CFU$~
f,3K;S-he:
/** construct the page by everyPage xyXVWd[
* @param everyPage a+9_sUq
* */ b=L|GV@$
public Page(int everyPage){ &##JZ
this.everyPage = everyPage; q^QLNKOH"
} 4s <ZKU
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/** The whole constructor */ S6_dmTV*
public Page(boolean hasPrePage, boolean hasNextPage, <4;L&3
vv`53 Pbw)
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int everyPage, int totalPage, KJV],6d
int currentPage, int beginIndex){ FuFICF7+C
this.hasPrePage = hasPrePage; Rp}Sm,w(
this.hasNextPage = hasNextPage; @ "CP@^
this.everyPage = everyPage; _Pl5?5eZj
this.totalPage = totalPage; M=EV^Tw-=
this.currentPage = currentPage; Of<Vr.m{R
this.beginIndex = beginIndex; A2`Xh#o
} "`[4(j
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/** e\*N Lj_(
* @return 8Urj;KkD
* Returns the beginIndex. VlxHZ
*/ _o>?\ :A
publicint getBeginIndex(){ 4X>=UO``L
return beginIndex; -8t&&fIA
} - KaU@t
ovvg"/>L
/** ,sp( (SF]1
* @param beginIndex ~eekv5
* The beginIndex to set. Cs^'g'
*/ aR%E"P-6l
publicvoid setBeginIndex(int beginIndex){ "^VPe[lA
this.beginIndex = beginIndex; !L@a;L
} N[xa=
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/** N8m3Wy
* @return R]TS5b-
* Returns the currentPage. M#SGZ~=1r
*/ 7KV0g1GQ
publicint getCurrentPage(){ mX@!O[f%9e
return currentPage; vu_ u\2d
} ;0O>$|kg
%I%OHs
/** 'w`9lIax
* @param currentPage EN@<z;
* The currentPage to set. Z$Vd8U;
*/ Iv>4o~t
publicvoid setCurrentPage(int currentPage){ OUtMel_
this.currentPage = currentPage; Y:]m~-T
} T^
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/** -AM(-
* @return rSNaflYAr
* Returns the everyPage. Hni?r!8r
*/ 'a=QCO
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publicint getEveryPage(){ HD8*>p.
return everyPage; kD_616
} w72\'
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/** eq7>-Dmi@
* @param everyPage jmn<gJ2Of
* The everyPage to set. #;s5=aH
*/ pLsWy&G
publicvoid setEveryPage(int everyPage){ pXoT@[}
this.everyPage = everyPage; n_P2l<F~/x
}
sf'+;
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/** o@DlK`
* @return >vfbXnN
* Returns the hasNextPage. u=PYm+q{
*/ {4HcecT
publicboolean getHasNextPage(){ Pfl8x
return hasNextPage; *dX
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} "\l#q$1h
@wx
/** ;;7:l,vy
* @param hasNextPage oO&R3zA1d
* The hasNextPage to set. ko`.nSZ-k
*/ TX$4x~:
publicvoid setHasNextPage(boolean hasNextPage){ E}8wnrxf
this.hasNextPage = hasNextPage; n>?eTlO3
} tY!GJusd
H.*aVb$
/** 4ZrRgx2MD
* @return rtZEK:.#
* Returns the hasPrePage. o$KW*aDp
*/ y}GFtRNG
publicboolean getHasPrePage(){ BFn4H%1
return hasPrePage; &a?k1R>
} GVUZn//
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/** o ^Ro 54i
* @param hasPrePage
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* The hasPrePage to set. P|QM0GI
*/ :L5k#E"u
publicvoid setHasPrePage(boolean hasPrePage){ n1;zml:7_
this.hasPrePage = hasPrePage; ?[c{pb,|
} gfly?)V nF
=.ReM_.
/** +CXtTasP
* @return Returns the totalPage. L(t!C~3
* 2OsS+6,[x
*/ GtpBd40"
publicint getTotalPage(){ kKz>]t"A
return totalPage; nr- 32u
} W*^_Ul|
D2 X~tl5<
/** K2!GpGZu
* @param totalPage %ZM"c
* The totalPage to set. [K""6D
*/ g1&>.V}!
publicvoid setTotalPage(int totalPage){ A#8J6xcSrL
this.totalPage = totalPage; e)*-<AGwC
} )8*}-z
;2[o>73F
} HJjx!7h
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 *NCkC
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个PageUtil,负责对Page对象进行构造: W?<<al*
java代码: <HH\VG\H6
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/*Created on 2005-4-14*/ PC3?eS}
package org.flyware.util.page; d9q`IZqee
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import org.apache.commons.logging.Log; <kKuis6h
import org.apache.commons.logging.LogFactory; aY0{v X
00/ RBs5
/** -8:/My
* @author Joa ]DjnzClx
* G124!^
*/ >f70-D28
publicclass PageUtil { aRy" _dZ2
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privatestaticfinal Log logger = LogFactory.getLog {$Z
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27
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(PageUtil.class); T'!p{Fbg;
8(g}/%1mt3
/** mC}
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* Use the origin page to create a new page kQD~v+u{`
* @param page W:hTRq
* @param totalRecords >?[?W|k7V
* @return BAojP1}+,
*/ ;$3epP
publicstatic Page createPage(Page page, int '&/~Sh$%
yVWt%o/
totalRecords){ (L`IL e*
return createPage(page.getEveryPage(), F},kfCFF
pgPm0+N
page.getCurrentPage(), totalRecords); SB,#y>Zv?
} !m8T< LtMl
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/** .EZ8yJj1Q
* the basic page utils not including exception L@.Trso
iy|;xBI,
handler Hi^Z`97c
* @param everyPage <Ok7-:OxA
* @param currentPage cZ3A~dTOR
* @param totalRecords pnUL+UYeM
* @return page sl`?9-_[
*/ 2M)E1q|a
publicstatic Page createPage(int everyPage, int ZB]234`0
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currentPage, int totalRecords){ a:s$[+'Y
everyPage = getEveryPage(everyPage); ' pIC~
currentPage = getCurrentPage(currentPage); ra8AUj~RX
int beginIndex = getBeginIndex(everyPage, *0m|`-
T
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currentPage); !QCErE;r
int totalPage = getTotalPage(everyPage, Y.kc,~vYL
E8 5TCS1
totalRecords); SNf~%B?`L
boolean hasNextPage = hasNextPage(currentPage, ( dh9aR_a
(:R5"|]@<x
totalPage); r@PVSH/
boolean hasPrePage = hasPrePage(currentPage); U+aiH U9
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returnnew Page(hasPrePage, hasNextPage, _Td#C1g3
everyPage, totalPage, KN&|&51p}
currentPage, J!">L+Zcx
QcX&q%*0
beginIndex); MRT<hB
} &UO/p/a
%3.
np
privatestaticint getEveryPage(int everyPage){ Hs6Kki1
return everyPage == 0 ? 10 : everyPage; 5Q: %f
} 3GrIHiCr
A)&CI6(
privatestaticint getCurrentPage(int currentPage){ %'VzN3Q5V
return currentPage == 0 ? 1 : currentPage; . BX*C
} S+*>""=
2*]
[M,L0c
privatestaticint getBeginIndex(int everyPage, int m -0EcA/
QZ[S,
c^
currentPage){ 7Sh1QDYZ
return(currentPage - 1) * everyPage; A`"?~_pHC
} #o,FVYYj
wFjQ1<s=
privatestaticint getTotalPage(int everyPage, int / %iS\R%ca
-9Ygn_M
totalRecords){ tY:,9eh7B
int totalPage = 0; +|x%a2?x:
b$- g"F
if(totalRecords % everyPage == 0) ='@k>Ka+
totalPage = totalRecords / everyPage; r%NzKPW'
else kq([c r
totalPage = totalRecords / everyPage + 1 ; t;u)_C,bmP
L+eK)Q
return totalPage;
m3^D~4
} J|@D @\?7
[k&7h,
privatestaticboolean hasPrePage(int currentPage){ ly6dl
return currentPage == 1 ? false : true; ` k(Q:
} }^P"R[+4u
e E(+
privatestaticboolean hasNextPage(int currentPage, D&pX0
UMT}2d%
int totalPage){ (+<66
TO
return currentPage == totalPage || totalPage == lHHx D
e)}=T0
s
0 ? false : true; 7#X`D
} ~yV?*"Hi
qT&zg@m
E*kZGHA
} kuq&; uk$Q
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xsN OjHk
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l
G({VK
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 z4zPR?%:
:bL^S1et
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1/6}E]-F
DF-.|-^9I
做法如下: sP~xe(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /CbiYm
kV8qpw}K
的信息,和一个结果集List: _lRIS_^;eE
java代码: hzpl;Mj
Bgp%hK
fZ^ad1o
/*Created on 2005-6-13*/ ~y
whl'"k
package com.adt.bo; ] ;HCt=I~
J4
U]_|
import java.util.List; IGab~`c-[
DJqJ6 z:'
import org.flyware.util.page.Page; zsR5"Vi=
=H}x
/** c>Ri6=C
* @author Joa #
@7I
*/ c `.BN(
publicclass Result { 09{ s'
a4Z e!l(
private Page page; G]mD_J1$
ULs'oT)K;
private List content; ikb77?.
tx Qr|\4k
/** a:4!z;2
|
* The default constructor i CB:p
*/ P^U.VXY}
public Result(){ Vock19P
super(); 7(P4KvkI
} ml!c0<
BxZ7Bk
/** x|()f3{.
* The constructor using fields @2hOy@V
* 1=`VaS
* @param page `tXd?E/e
* @param content d<WNN1f
*/ o`
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public Result(Page page, List content){ tCPK_Wws?Z
this.page = page; "5?1S-Vl
this.content = content; /}iBrMD{[
} fr$6&HDZ9
;vbMC74J#
/** SMfa(+V I
* @return Returns the content. A5]yC\*zt
*/ e<FMeg7n
publicList getContent(){ Z`zLrXPD)
return content; 4X+I2CD
} 17 0r 5
7#7|+%W0
/** rp2g./2
* @return Returns the page. !\O!Du
*/ FJxb!-0&
public Page getPage(){ 7KJ0>0~Et
return page; @2-;,VL3
} 9`? M-U
V'UFc>{o
/** PtzT><
* @param content ~[~#PO
* The content to set. Pv3G?u=4
*/ #\ysn|!J,
public void setContent(List content){ @ `mke4>_
this.content = content; e~cg
(.
} |x>5 T}
<aI}+
/** Cb.M
* @param page */K]sQZa
* The page to set. w ykaf
*/ 6UL9+9[C
publicvoid setPage(Page page){ z<0/#OP'
this.page = page; k`5K&
} Y]uVA`%"b
} 5r~hs6H
v(Sh+p
]^i^L
]9JH.fF
E\cX
2. 编写业务逻辑接口,并实现它(UserManager, iM6(bmc.
b*{UO
UserManagerImpl) $jv"$0Fc
java代码: %Nob B
WN#2<XjG
XD_!5+\H1
/*Created on 2005-7-15*/ _={mKKoHs
package com.adt.service; J8Vzf$t};
>l=^3B,j
import net.sf.hibernate.HibernateException; IY
mkZ?cW
HS\'{4P
import org.flyware.util.page.Page; bw+IH-b
"pH;0[r]
import com.adt.bo.Result; dy'lM ;@-
`>)pqI%L[g
/** !;hp
* @author Joa i'^! SEt
*/ f|)~_JH
publicinterface UserManager { vg_PMy\
x\VP
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public Result listUser(Page page)throws )@y7 qb
02T'B&&~
HibernateException; !C^>tmqS
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} {MDM= ;WP_
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]U
0[N1SY\lj
LB}J7yEQvj
_9Rj,
java代码: R\/tKZJjb
_5$L`&
crSqbL
/*Created on 2005-7-15*/ Y4X`(\A
package com.adt.service.impl; @e$EwCV,
jR@>~t[}o
import java.util.List; $d,{I8d
yUO%@;
import net.sf.hibernate.HibernateException; Uty0mc(
t%f>*}*P*
import org.flyware.util.page.Page; sb?!U"v.'
import org.flyware.util.page.PageUtil; ,Z! I ^
C',uY7}<
import com.adt.bo.Result; Sl%6F!
import com.adt.dao.UserDAO; /;E=)(w
import com.adt.exception.ObjectNotFoundException; :_,3")-v
import com.adt.service.UserManager; :C,}DyZy
-pQ?ybQ
/** -C!m#"PDW
* @author Joa tT]mMlKJ
*/ 5N bq9YY
publicclass UserManagerImpl implements UserManager { =ReSlt
40dwp*/!
private UserDAO userDAO; *!3qO^b?
pZt>rv
/** Hc8!cATQk
* @param userDAO The userDAO to set.
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*/ %,aSD#l`f
publicvoid setUserDAO(UserDAO userDAO){ }LLQ+
this.userDAO = userDAO; 5 [4{1v
} Re'3 bs:+
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/* (non-Javadoc) Ae1b`%To
* @see com.adt.service.UserManager#listUser A0v@L6m-O
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(org.flyware.util.page.Page) E]^n\bE%
*/ LZE9]Gd
public Result listUser(Page page)throws jJ,y+o
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HibernateException, ObjectNotFoundException { s%6L94\t
int totalRecords = userDAO.getUserCount(); NdXC8
if(totalRecords == 0) t\Qm2Q)>
throw new ObjectNotFoundException kqq1;Kd
&h=f
("userNotExist"); lZ <D,&
page = PageUtil.createPage(page, totalRecords); t2rZ%[O
List users = userDAO.getUserByPage(page); 5Kk}sxol
returnnew Result(page, users); 7;]IlR6
} R"\(a
#yEkd2Vy{
} vu*9(t)EC
[ lK`~MlQ
K2V?[O#
-_]Ceq/
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ng6E&<Z
#c'}_s2F[
询,接下来编写UserDAO的代码: =2vZqGO30
3. UserDAO 和 UserDAOImpl: lh!8u<yv*
java代码: Uv=)y^H~*A
4!
F$nmG)
5-S-r9
/*Created on 2005-7-15*/ `FX?P`\@I
package com.adt.dao; w]N;HlU
[=u@6Y
import java.util.List; 0}T56aD=!
jW[EjhsH
import org.flyware.util.page.Page; &?}h)U#:
wOrj-Smx
import net.sf.hibernate.HibernateException; %?8.UW\m
vy>(?[
/** ]I;owk,
* @author Joa BV\~Dm]"
*/ Z uP3/d
publicinterface UserDAO extends BaseDAO { 5Z#(C#
TY` R_
publicList getUserByName(String name)throws ?,[$8V
{?X +Yw
HibernateException;
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publicint getUserCount()throws HibernateException; w[EEA_\
n-<`Z NMU
publicList getUserByPage(Page page)throws Vn_>c#B
WM=)K1p0u
HibernateException; $%ww$3
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} 2o W'B^-
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<\d2)Iv
xr!A>q+@i
~i>'3j0@k
java代码: |]-~yYqP3
eQqCRXx
VjZb\
d4
/*Created on 2005-7-15*/ #ZHKq7
package com.adt.dao.impl; V_|HzYJJ5
(+u&b< <6N
import java.util.List; `;m0GU68
Z1(!syg
import org.flyware.util.page.Page; Cwji,*
E|6@h8#
import net.sf.hibernate.HibernateException; UyF;sw
import net.sf.hibernate.Query; p-7?S^!l
x'%vL",%
import com.adt.dao.UserDAO; 8*uaI7;*
4~WSIR-
/** zXwdU58
* @author Joa ,.Lo)[(
*/ PX?^v8wlqL
public class UserDAOImpl extends BaseDAOHibernateImpl ]a:T]x6'
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implements UserDAO { 'p%w_VbI
=H}}dC<)
/* (non-Javadoc) YC*`n3D|'
* @see com.adt.dao.UserDAO#getUserByName !Uhc jfq`e
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(java.lang.String) y35e3
*/ s(MdjWw
publicList getUserByName(String name)throws 90H/Txq
;BHIss7
HibernateException { \z.p [;'ir
String querySentence = "FROM user in class |I.5]r-EK
GB6(WAmr
com.adt.po.User WHERE user.name=:name"; (YYwn@NGj
Query query = getSession().createQuery W)Yo-%
i}))6
(querySentence); 4!?4Tc!X
query.setParameter("name", name); a4q02 cV
return query.list(); &kH7_Lz
} oL9ELtb]s
Kf6D$}
/* (non-Javadoc) 2D3mTpw
* @see com.adt.dao.UserDAO#getUserCount() Ka"1gbJ|
*/ oV~S4|9:
publicint getUserCount()throws HibernateException { wFBSux$
int count = 0; 4@M}5WJ7
String querySentence = "SELECT count(*) FROM owO&[D/
p\]rxtm
user in class com.adt.po.User"; 1}CJ&
Query query = getSession().createQuery SNH AL F
2k`Q+[?{q>
(querySentence); j?!/#'
count = ((Integer)query.iterate().next dmMrZ1u2
gLbTZM4i
()).intValue(); )_Iu7b
return count; 9a'}j#mJo
} @\=4 Rin/q
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/* (non-Javadoc) g_"B:DR
* @see com.adt.dao.UserDAO#getUserByPage J^pq<
!zfV(&
(org.flyware.util.page.Page) O%Qz6R
*/ SQJ4}w>i
publicList getUserByPage(Page page)throws 48mTL+*
ZYz8ul$E
HibernateException { ;#7:}>}rO
String querySentence = "FROM user in class id/y_ekfP
3E8 Gh>J_
com.adt.po.User"; 01+TVWKX
Query query = getSession().createQuery C3C&hq\%
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(querySentence); W{kTM4
query.setFirstResult(page.getBeginIndex()) asbFNJG{
.setMaxResults(page.getEveryPage()); 6N.MCB^
return query.list(); S&'-wAEd
} <mQ9YO#
&tlU.Whk+
} d ?,wEfwp
<!?ZH"F0
t&G #%
1kh()IrA
P0-K/_g
至此,一个完整的分页程序完成。前台的只需要调用 QEY#U|
byIP]7Ld
userManager.listUser(page)即可得到一个Page对象和结果集对象 {\
BFWGX
//^{u[lr
的综合体,而传入的参数page对象则可以由前台传入,如果用 =>xyJ->R
iDlg>UYd
webwork,甚至可以直接在配置文件中指定。 U
H6
Jvt
Dwah_ p8
下面给出一个webwork调用示例: |b|bL 7nx
java代码: .gw6W0\F
c+UZ UgP
-qB{TA-.\
/*Created on 2005-6-17*/ 4'L.I%#tZ
package com.adt.action.user; ^
}|$_
#2qv"ntW
import java.util.List; va;fT+k=
s&6/fa
import org.apache.commons.logging.Log; lZD"7om
import org.apache.commons.logging.LogFactory; b*cVC^{Dy
import org.flyware.util.page.Page; XC[bEp$
~*RBMHs
import com.adt.bo.Result; G 2FD'Sf
import com.adt.service.UserService; ;QQ/bM&I
import com.opensymphony.xwork.Action; W_|7hwr
h
x
hl
/** sq}uq![?M
* @author Joa qD5)AdCGO
*/ !l1jQq_mK
publicclass ListUser implementsAction{ 1K{hj%
ljk,R
G
privatestaticfinal Log logger = LogFactory.getLog +Pb@@C&
/Au7X'}
(ListUser.class); 8Y~\:3&1<
S| l%JM^
private UserService userService; tQIz
F3<Ip~K
private Page page; *Q,9 [k
;C+
_K S
privateList users; nb U?:=P
O3(H_(P
/* .\|}5J9W
* (non-Javadoc) Z(o]8*;Ai
* QZ_8r#2x
* @see com.opensymphony.xwork.Action#execute() L7$1 rO<
*/ p/Lk'h~
publicString execute()throwsException{ d{RMX<;G
Result result = userService.listUser(page); m7,;Hr(
page = result.getPage(); ddvtBAX
users = result.getContent(); u$y5?n|
return SUCCESS; fBct%M 3
} 3>buZ6vh
5s1XO*s)>X
/** &,iPI2`O A
* @return Returns the page. k3r<']S^
*/ bODyJ7=[
public Page getPage(){ 3Cl&1K #5
return page; 420yaw/":
} ^97\TmzP{
l =^ ^l`
/** q|N4d9/b
* @return Returns the users. OJPi*i 5*
*/ c:_dW;MJ0
publicList getUsers(){ ;F\sMf{
return users; #l-/!j
} ? ]hS^&
(/3E,6gMk^
/** 6yXMre)YV
* @param page Mg=R**s1x%
* The page to set. f&`yiy_
*/ kDK0L3}nr]
publicvoid setPage(Page page){ $C9['GGR
this.page = page; D 13bQ&\B-
} 5:X^Q.f;
vU,;asgy
/** 1F94e)M)"
* @param users BYWs\6vK
* The users to set. Rln@9muXA
*/ "!_,N@\t
publicvoid setUsers(List users){ rd4mAX6@
this.users = users; ' |
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} td\'BV
gl!F)RdH
/** hwd{^
* @param userService a3[lZPQe
* The userService to set. $h8,QPy
*/ h&:6S
publicvoid setUserService(UserService userService){ .Sjg
this.userService = userService; WO"<s{v
} x @uowx_&m
} ?4MZT5 .
+"Mlj$O
HWi: CDgm
H0Ck%5
^ lM.lS>)
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, wb/@g=`d
eAbp5}B
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 }tUr
V
p#tbN5i[{7
么只需要: yU< "tg E
java代码: ]5j1p6;(`
uw9w{3]0f
lxXIu8
<?xml version="1.0"?> @[w.!GW%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork glgXSOj
yu@u0vlc
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ,U#FtOec
spv'r!*\ed
1.0.dtd"> +]jJ: V
4+4C0/$Y
<xwork> uE:`Fo=y
@8'LI8 \/
<package name="user" extends="webwork- iVqXf;eB!5
4dI=
interceptors"> C9"yu&l
|A19IXZ\
<!-- The default interceptor stack name a
qIpO
,ku3;58O<
--> A!fRpN
<default-interceptor-ref TrmrA$5f
0%>_fMa A
name="myDefaultWebStack"/> f
l*O)r
H"J>wIuGX
<action name="listUser" G.sf>.[
RL~]mI!U
class="com.adt.action.user.ListUser"> 6SN$El 0|G
<param x] j&Knli
LCkaSv/[RB
name="page.everyPage">10</param> \s">trXwX
<result b<"LUM*;
>`u/#mrd
name="success">/user/user_list.jsp</result> g,d'&r"JWt
</action> b{hdEb
i@hW" [A
</package> C{P:1ELYXH
w]=c^@t_
</xwork> rz]M}!>k
cux<7#6af
v.Zr,Z=eV
25/OV"Z
?emYLw
Y5$VWUrB
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ]O.Z4+6w
k#pNk7;MZ
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 71!'k>]h
w>uo-88
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 V{yk
Tl`HFZQ1
f4r)g2Zb[
h^=9R6im
RqRyZ*n
我写的一个用于分页的类,用了泛型了,hoho Nr:%yvk%s
n>i}O!agg
java代码: e.?;mD
f~Q]"I8w
Xwt}WSdF`k
package com.intokr.util; 9Jj:d)E>o
i!dQ
Sdf
import java.util.List; d+158qQOh]
+EE(d/f
/** W+ D{4:
* 用于分页的类<br> RLr^6+v)U
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?-D'xqc
* u$V8fus0
* @version 0.01 m
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* @author cheng J^)=8cy
*/ ^.~m4t`U
public class Paginator<E> { NB?y/v
privateint count = 0; // 总记录数 z{ MO~d9
privateint p = 1; // 页编号 yjj)+eJ(Q
privateint num = 20; // 每页的记录数 $|pD}
privateList<E> results = null; // 结果 ,ou&WI yC
!;h`J:dN
/** !<W^Fh
* 结果总数 diDB>W
*/ Cso-WG,
publicint getCount(){ Yi+$g
return count; z`KP
}-
} 8bI;xjK^Q
vfPIC!
publicvoid setCount(int count){ wH N5H
this.count = count; RI#o9d"x}
} t'im\_$F
d+Au`'{>
/** rugR>&mea
* 本结果所在的页码,从1开始 FvT;8ik:3
* &NB"[Mm:@
* @return Returns the pageNo. L|N[.V9
*/ q$BS@
publicint getP(){ ^U[yk'!Y
return p; ~fR-cXj"
} UhVJ! NrT
Zz@wbhMV
/** >{@:p`*
* if(p<=0) p=1 ] R-<v&O
* YMD&U
* @param p mdy+ >e<
*/ c3q @]|aI
publicvoid setP(int p){ YqNI:znm-
if(p <= 0) O)?
p = 1; ! j-JMa?
this.p = p; :1,xs e
} AAPfU_:
^
NQ qq\h
/** lJ/{.uK
* 每页记录数量 I^itlQ
*/ :Co+haW
publicint getNum(){ $ Ov#^wfA
return num; gPzp/I
} T$r?LIa ,Q
}Asp=<kCc
/** (3fU2{sm
* if(num<1) num=1 F|{F'UXj|
*/ @(_f}SgfE
publicvoid setNum(int num){ XbMAcgS
if(num < 1) W9%B9~\G;+
num = 1; }&:F,q*
this.num = num; CY
i{WV(:
} c`x[C
@!:_r5R~N
/** %x zgTZ
* 获得总页数 7<p?E7
*/ FST}:*dOe5
publicint getPageNum(){ OJ2I (8P
return(count - 1) / num + 1; ;$>wuc'L
} * Qe{CE
}$T!qMst{
/** U**v'%{s
* 获得本页的开始编号,为 (p-1)*num+1 1?5UVv_F
*/ q26%Z)'nf
publicint getStart(){ K`% I!Br
return(p - 1) * num + 1; cAAyyc"yJ
} kx_PMpc
Qpaan
/** n`af2I2
* @return Returns the results. %V&I${z
*/ `.8#q^
publicList<E> getResults(){ .ugQH<B
return results; I}{Xv#@o
} VG+WVk
*S$`/X
public void setResults(List<E> results){ UZq1qn@+
this.results = results; '#faNVPABh
} NDaM;`
WCPl}7>
public String toString(){ &?@5G
StringBuilder buff = new StringBuilder YDMimis\H5
/n|`a1!
(); A"8"e*
buff.append("{"); U%,N"]`
buff.append("count:").append(count); ]A2l%V_7
buff.append(",p:").append(p); u/8urxpy
buff.append(",nump:").append(num); =P.m5e<
buff.append(",results:").append t% f6P
CN"hx-f
(results); E-_Q3^
buff.append("}"); &R
"Q
return buff.toString(); &]? X"K
} =1}Umn|ZLS
\dz@hJl:
} 'l}T_7g
Uc3-n`C
iS"(