Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \b x$i*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 CTa57R
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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 F41=b4/
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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 yf+)6D -9n
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分页支持类: 7NGxa6wi
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java代码: 5;EvNu
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package com.javaeye.common.util; QWYJ*
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import java.util.List; :F?C)F
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publicclass PaginationSupport { 5b*C1HS@X
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publicfinalstaticint PAGESIZE = 30; i_%_ x*
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privateint pageSize = PAGESIZE; N6:`/f+A>T
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privateList items; 4hj|cCrO
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privateint totalCount; Zy/_
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privateint[] indexes = newint[0]; 0=YI@@n)
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privateint startIndex = 0; zDG b7S{
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public PaginationSupport(List items, int 9'B `]/L
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totalCount){ Dd|VMW=
setPageSize(PAGESIZE); 2^7`mES
setTotalCount(totalCount); h376Be{P
setItems(items); <hyKu
setStartIndex(0); ?J0y|
} Bzf^ivT3L
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public PaginationSupport(List items, int $&c*'3
*.[.
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totalCount, int startIndex){ 'w aaw_>b
setPageSize(PAGESIZE); \FaP|28h
setTotalCount(totalCount); @0''k
setItems(items); jP.dDYc
setStartIndex(startIndex); 8s@3hXD&
} >t+P(*u
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public PaginationSupport(List items, int [a(#1
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totalCount, int pageSize, int startIndex){ P%n>Tg80M
setPageSize(pageSize); a<e[e>
setTotalCount(totalCount); SpBy3wd
setItems(items); ~xTt204S
setStartIndex(startIndex); -9?]IIVb
} ;_=&-mz
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publicList getItems(){ Mtx 4'WZ
return items; ~W/z96'
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} V7/Rby Q
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publicvoid setItems(List items){ 53h0UL
this.items = items; ca9X19NG
} ckn(`I
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publicint getPageSize(){ HzJz+ x:
return pageSize; ]?4hyN
} (9)Q ' 'S
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publicvoid setPageSize(int pageSize){ ['D]>Ot68
this.pageSize = pageSize; <_+X 88
} BA.uw_^4
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publicint getTotalCount(){ 7_t'( /yu
return totalCount; zQ PQ
} E{(;@PzE
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publicvoid setTotalCount(int totalCount){ i.#:zU%o
if(totalCount > 0){ I/N *gy?*
this.totalCount = totalCount; k5)om;.w
int count = totalCount / `]aeI'[}R
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pageSize; Hn:Crl y#
if(totalCount % pageSize > 0) 7+*WH|Z@
count++; D%Z|
indexes = newint[count]; W+*
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for(int i = 0; i < count; i++){ '+
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indexes = pageSize * +7}]E1Uf
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} HaYo!.(Fv
}else{ ;*J
this.totalCount = 0; /L3:
} B5QFK
} 5V-I1B&
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publicint[] getIndexes(){ Bw.i}3UT6
return indexes; Ys7]B9/1O
} 'GScszz
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publicvoid setIndexes(int[] indexes){ < %Y}R\s?
this.indexes = indexes; ,x $,l
} ^zr`;cJ+c
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publicint getStartIndex(){ +C)~bb*
return startIndex; i#O SC5ZI
} UxBpdm%dvP
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publicvoid setStartIndex(int startIndex){ VU#7%ufu&
if(totalCount <= 0) jiGTA:v
this.startIndex = 0; 2<6UwF
elseif(startIndex >= totalCount) p7~!z.)o
this.startIndex = indexes #9s,#
}
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[indexes.length - 1]; xD 7]C|8o
elseif(startIndex < 0) +`15le`R
this.startIndex = 0; *WZA9G#V5
else{ 4ppz,L,4
this.startIndex = indexes JGZBL{8
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[startIndex / pageSize]; I+(nu47ZT
} qgB_=Q#E
} 9H~n_
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publicint getNextIndex(){ i~72bMwsA
int nextIndex = getStartIndex() + =pr7G+_u
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pageSize; ~M$Wd2Th
if(nextIndex >= totalCount) G/W>S,(
return getStartIndex(); atzX;@"K
else >GuM]qn
return nextIndex; dWW.Y*339
} 6~+emlD
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publicint getPreviousIndex(){ 3U}%2ARo_
int previousIndex = getStartIndex() - ^f@=:eWI
[><Tm\(:
pageSize; @+DX.9
if(previousIndex < 0) fsXy"#mOkD
return0; d_CT$
else tBSW|0
return previousIndex; R!1p^~/
} {)Xy%QV
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} 62u4-}JzF
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抽象业务类 _Ey5n!0:
java代码: ,z6~?6m
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/** 1*7@BP5
* Created on 2005-7-12 Zd&S@Z
*/ ('~LMu_
package com.javaeye.common.business; &Qm@9I s
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import java.io.Serializable; ,,TnIouy
import java.util.List; $Q0n
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import org.hibernate.Criteria; ]'S^]
import org.hibernate.HibernateException; 6B-16
import org.hibernate.Session; t,'<gI
import org.hibernate.criterion.DetachedCriteria; JtZ7ti
import org.hibernate.criterion.Projections; =M-p/uB]
import AwN!;t_0+N
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org.springframework.orm.hibernate3.HibernateCallback; LQ% `c
import t<qiGDJ<d
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org.springframework.orm.hibernate3.support.HibernateDaoS N g,j#
}7X%'Bg=M
upport;
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import com.javaeye.common.util.PaginationSupport; adw2x pj
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public abstract class AbstractManager extends {Ha57Wk8D
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HibernateDaoSupport { Pc9H0\+Xk
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privateboolean cacheQueries = false; iQ{VY
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privateString queryCacheRegion; 28nFRr
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publicvoid setCacheQueries(boolean ~K=b\xc^
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cacheQueries){ pJ{Y
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this.cacheQueries = cacheQueries; < vP=zk
} ?#fQ~ s
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publicvoid setQueryCacheRegion(String gFh*eC o
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queryCacheRegion){ _-\#i
this.queryCacheRegion = cZ06Kx..
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queryCacheRegion; ,vDbp?)'U
} s @C}P
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publicvoid save(finalObject entity){ <uJ@:oWG7
getHibernateTemplate().save(entity); |g~ZfnP_%
} \DzGQ{`~m
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publicvoid persist(finalObject entity){ t^L]/$q
getHibernateTemplate().save(entity); 5X+A"X
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} K%d&EYoW]
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publicvoid update(finalObject entity){ 2?x4vI
np;
getHibernateTemplate().update(entity); BuwY3F\-O
} Lr<cMK<
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publicvoid delete(finalObject entity){ `2snz1>!j
getHibernateTemplate().delete(entity); u&NV,6Fj2[
} *](iS
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publicObject load(finalClass entity, M?qy(zb
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finalSerializable id){ D]}G.v1
return getHibernateTemplate().load Yz b XuJ4
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(entity, id); a
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} kP"9&R`E
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publicObject get(finalClass entity, VE24ToI?W"
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finalSerializable id){ =Uh$&m
return getHibernateTemplate().get ^s=8!=A(
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(entity, id); PM+[,H
} =}*0-\QG
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publicList findAll(finalClass entity){ OYd !v`<
return getHibernateTemplate().find("from `]X>V,
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" + entity.getName()); vbNBLCwug
} ]!
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publicList findByNamedQuery(finalString 9my^Y9B
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namedQuery){ OH88n69
return getHibernateTemplate Z7#+pPt!
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().findByNamedQuery(namedQuery); eJSxn1GW
} jF>[?L
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publicList findByNamedQuery(finalString query, ;I*o@x_
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finalObject parameter){ `g,..Ns-r
return getHibernateTemplate NgwbQ7)
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().findByNamedQuery(query, parameter); xmX 4qtAL
} /B3i C#?
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publicList findByNamedQuery(finalString query, ^"g~-
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finalObject[] parameters){ ,>M[@4`,U
return getHibernateTemplate U17d>]ka
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().findByNamedQuery(query, parameters); P3%5?.S
} Kgv T"s.
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publicList find(finalString query){ AdmC&!nH
return getHibernateTemplate().find :+Z%; Dc
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(query); >Q/Dk7 #
} VQs5"K"
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publicList find(finalString query, finalObject GeqPRah
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parameter){ 5bIw?%dk(
return getHibernateTemplate().find SKtr tm
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(query, parameter); =vPj%oLp'a
} lk!@?
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public PaginationSupport findPageByCriteria fox6)Uot
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(final DetachedCriteria detachedCriteria){ FlQGgVN
return findPageByCriteria @c#(.=
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =v\.h=~~
} LscGTs,
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public PaginationSupport findPageByCriteria 5tnlrqC
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(final DetachedCriteria detachedCriteria, finalint 0%B/,/PxD
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startIndex){ 3
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return findPageByCriteria /efUjkP
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(detachedCriteria, PaginationSupport.PAGESIZE, "N;EL0=
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startIndex); _M1 %Z~
} "&] -2(
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public PaginationSupport findPageByCriteria 8(De^H lO
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(final DetachedCriteria detachedCriteria, finalint ~~.}ah/_d
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pageSize, xG 1nGO
finalint startIndex){ YR70BOxK
return(PaginationSupport) Smh,zCc>s
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getHibernateTemplate().execute(new HibernateCallback(){ [7-?7mp!B
publicObject doInHibernate SJLis"8
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(Session session)throws HibernateException { zCA2X
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Criteria criteria = [Pp'Ye~K@c
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detachedCriteria.getExecutableCriteria(session); K}y
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int totalCount = xo)P?-
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((Integer) criteria.setProjection(Projections.rowCount @iiT<
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()).uniqueResult()).intValue(); ^
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criteria.setProjection W)/#0*7
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(null); ^q&x7Kv%
List items = K"6vXv4QO
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criteria.setFirstResult(startIndex).setMaxResults u
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(pageSize).list(); b>W%t
PaginationSupport ps = R_KH"`q
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new PaginationSupport(items, totalCount, pageSize,
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startIndex); :s,Z<^5a)g
return ps; ~u{uZ(~
} SM'|+ d
}, true); 0K+ne0I
} kM6
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public List findAllByCriteria(final |)&%A%m
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DetachedCriteria detachedCriteria){ 9?$i?
return(List) getHibernateTemplate (Z*!#}z`
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().execute(new HibernateCallback(){ !i50QA|(G
publicObject doInHibernate gi8FHSU|G
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(Session session)throws HibernateException { R-:2HRaA
Criteria criteria = ?[AD=rUC
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detachedCriteria.getExecutableCriteria(session); Z;i:](
return criteria.list(); Dv"9qk
} sK{e*[I>W
}, true); ZNoDFf*h
} 'F<TSy|4kI
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public int getCountByCriteria(final XSDpRo
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DetachedCriteria detachedCriteria){ Ri{=]$
Integer count = (Integer) r$1Qf}J3=
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getHibernateTemplate().execute(new HibernateCallback(){ ok[i<zl;'
publicObject doInHibernate {=WgzP
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(Session session)throws HibernateException { hM{bavd
Criteria criteria = NUZl`fu1Z4
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detachedCriteria.getExecutableCriteria(session); 8y L Y
return zda 3
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criteria.setProjection(Projections.rowCount hrn+UL:d
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()).uniqueResult(); @- xjfC\d
} ^y::jK
}, true); G2D$aSh
return count.intValue(); ,hVli/
} x4 yR8n(
} pb}*\/s
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用户在web层构造查询条件detachedCriteria,和可选的 TxD#9]Q`
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $]d^-{|
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PaginationSupport的实例ps。 Y|n"dMrL
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ps.getItems()得到已分页好的结果集 e=
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ps.getIndexes()得到分页索引的数组 yAt^;
ps.getTotalCount()得到总结果数 +whDU2 "
ps.getStartIndex()当前分页索引 \e;iT\=.(
ps.getNextIndex()下一页索引 fu5=k:/c
ps.getPreviousIndex()上一页索引 A&VG~r$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 C _Dn{
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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 r&CiSMS*
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一下代码重构了。 uFE)17E
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我把原本我的做法也提供出来供大家讨论吧: 3w=J'(RU
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首先,为了实现分页查询,我封装了一个Page类: 5+vaE
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java代码: _/|\aqF.
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/*Created on 2005-4-14*/ w:0E(z
package org.flyware.util.page; p{_" bB
@C$]//;
/** s<Ziegmw|g
* @author Joa d=(mw_-?
* LoV<:|GTI
*/ ax`o>_)
publicclass Page { 9w"*y#_
OXA7w.^
/** imply if the page has previous page */ *wearCPeJ
privateboolean hasPrePage; 8LKiS
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/** imply if the page has next page */ N7"W{"3D
privateboolean hasNextPage; L0,'mS
s;e\ pt
/** the number of every page */ 3`g^
privateint everyPage; b}`TLn
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/** the total page number */ <I?Zk80
privateint totalPage; -RwE%cr
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/** the number of current page */ X'srL j.
privateint currentPage; dV_G1'
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/** the begin index of the records by the current la!~\wpa
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query */ lxx2H1([
privateint beginIndex; RZLq]8pM
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/** The default constructor */ @"A4$`Xi3
public Page(){ oR'm2d ^
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} (QEG4&9
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/** construct the page by everyPage @ Y+oiB~Y
* @param everyPage -w2/w@&
* */ J1k>07}|
public Page(int everyPage){ K-v#.e4
this.everyPage = everyPage; D*jM1w_`
} pi(m7Ci"
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/** The whole constructor */ 9[4xFE?|
public Page(boolean hasPrePage, boolean hasNextPage, Wr
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int everyPage, int totalPage, c 9Mz]1@f
int currentPage, int beginIndex){ {: /}NpA$
this.hasPrePage = hasPrePage; Txu/{M,
this.hasNextPage = hasNextPage; 6K^#?Bn;
this.everyPage = everyPage; BPrt'Nc
this.totalPage = totalPage; { 6il`>=C
this.currentPage = currentPage; * 4'"2"
this.beginIndex = beginIndex; {7[Ox<Ho
} N2G{<>=
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/** F9PxSk_\9
* @return V~GDPJ+
* Returns the beginIndex. /~1+i'7V.,
*/ dysS9a,
publicint getBeginIndex(){ %9"H
return beginIndex; [Xkx_B
} _a, s
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/** Rq -ZL{LR7
* @param beginIndex -"x$ZnHU
* The beginIndex to set. E.h*g8bXe
*/ 0GwR~Z}Z
publicvoid setBeginIndex(int beginIndex){ 43cE`9~
this.beginIndex = beginIndex; ).O)p9
} KNl$3nX
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/** ~%oR[B7=|
* @return Eci\a]
* Returns the currentPage. @7}W=HB
*/ >P(.:_^p
publicint getCurrentPage(){ kh<2BOV
return currentPage; F4QVAOM]U
} :jf3HG
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/** " bG2:
* @param currentPage u8^lB7!e/
* The currentPage to set. `[A];]
*/ *CMx- _
publicvoid setCurrentPage(int currentPage){ BT$_@%ea&
this.currentPage = currentPage; )J |6 -C
} TeQV?ZQ#}
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/** DU^loB+
* @return P?<y%c<
* Returns the everyPage. , gHDx
*/ _1^'(5f$
publicint getEveryPage(){ crCJrN=
return everyPage; \8tsDG(1 '
} H,J8M{
)7@0[>
/** )oZ dj`
* @param everyPage "@kaHIf[
* The everyPage to set. f$( e\++
*/ 6!o1XQr=Z
publicvoid setEveryPage(int everyPage){ gw(z1L5
n
this.everyPage = everyPage; K3C <{#r
} <@}9Bid!o
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/** jIyQ]:* p
* @return ICCc./l|
* Returns the hasNextPage. M5B# TAybC
*/ zs;JJk^
publicboolean getHasNextPage(){ a*;b^Ze`v
return hasNextPage; (H]AR8%W
} *Ex|9FCt$
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/** @HW*09TG
* @param hasNextPage ESs\O?nO
* The hasNextPage to set. :Tc^y%b0
*/ iLT}oKF2N;
publicvoid setHasNextPage(boolean hasNextPage){ 9mgIUjz
this.hasNextPage = hasNextPage; ^Cmyx3O^
} 9Flb|G%
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/** 6@o*xK7L
* @return J,G
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* Returns the hasPrePage. QJNFA}*>
*/ mOSv9w#,
publicboolean getHasPrePage(){ 4Hg9N}
return hasPrePage; kza5ab
} V]&\fk-{
R]dg_Da
/** d-m7}2c
* @param hasPrePage l:%GH
* The hasPrePage to set. 0YzpZW"+
*/ V)^+?B)T
publicvoid setHasPrePage(boolean hasPrePage){ +p^u^a
this.hasPrePage = hasPrePage; neh(<>
} $M#>9QHhc
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/** !wNO8;(
* @return Returns the totalPage. l2d{ 73h
* l0]
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*/ 4 :=]<sc,
publicint getTotalPage(){ a?.=V
return totalPage; @;kSx":b
} |}1dFp
hph4 `{T
/** h![#;>(
* @param totalPage f?b"i A(6
* The totalPage to set. P2!C|SLK
*/ zX~MC?,W1
publicvoid setTotalPage(int totalPage){ l,:F
this.totalPage = totalPage; Q&&@v4L
} m*;ERK
v:p} B$
} g>sSS8RO
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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 iLz@5Zj8
23?rEhKe
个PageUtil,负责对Page对象进行构造: :]c3|J
java代码: h~26WLf.
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/*Created on 2005-4-14*/ :KN-F86i
package org.flyware.util.page;
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import org.apache.commons.logging.Log; :LTN!jj
import org.apache.commons.logging.LogFactory; _|]x2xb)
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/** zJXplvaL;
* @author Joa z=FZiH
* l@\FWWQ
*/ Tr|JYLwF
publicclass PageUtil { *kVV+H<X|b
b\ PgVBf9
privatestaticfinal Log logger = LogFactory.getLog +3`alHUK
[V!tVDs&'o
(PageUtil.class); ':}\4j&{E
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/** ]d`VT)~vje
* Use the origin page to create a new page *dF>_F
* @param page DJ%PWlK5
* @param totalRecords |' .
* @return &?vgP!d&M
*/ i&k7-<
publicstatic Page createPage(Page page, int vj*%Q(E6Pt
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totalRecords){ e*!kZAf
return createPage(page.getEveryPage(), qVPeB,kIz
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page.getCurrentPage(), totalRecords); CNIsZv@Q
} h1{3njdr
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/** 5?L<N:;J_
* the basic page utils not including exception KU;9}!#
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handler )jC%a6G!
* @param everyPage Ha#>G<;n
* @param currentPage WKU=.sY
* @param totalRecords X(C$@N
* @return page PzGWff!*n
*/ [:V$y1
publicstatic Page createPage(int everyPage, int vI]N^j2%
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currentPage, int totalRecords){ 5PW^j\G-f
everyPage = getEveryPage(everyPage); rGkyGz8>
currentPage = getCurrentPage(currentPage); c)tfAD(N8x
int beginIndex = getBeginIndex(everyPage, uGt-l4
<,(,jU)j
currentPage); KYP!Rs/j.
int totalPage = getTotalPage(everyPage, d %#b:(,
c(%|: P^
totalRecords); oE~Bq/p
boolean hasNextPage = hasNextPage(currentPage, .~}1+\~5
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totalPage); }75e:w[
boolean hasPrePage = hasPrePage(currentPage); =2 kG%9
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returnnew Page(hasPrePage, hasNextPage, W%)Y#C
everyPage, totalPage, 9/7u*>:
currentPage, cAc@n6[`3
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beginIndex);
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} frQ{iUx
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privatestaticint getEveryPage(int everyPage){ J$!iq|
return everyPage == 0 ? 10 : everyPage; *#Wdc O`-
} @A5?3(e
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privatestaticint getCurrentPage(int currentPage){ >*n0n!vF
return currentPage == 0 ? 1 : currentPage; 1QJL .
} BUR*n;V`
QIgNsz
privatestaticint getBeginIndex(int everyPage, int 9C\Fq-
iIogx8[
currentPage){ _y3Xb`0a
return(currentPage - 1) * everyPage; Lk$B{2^n
} Z<4AL\l 98
^I)N. 5
privatestaticint getTotalPage(int everyPage, int e$pV%5=
JZ#[
2mLh
totalRecords){ * H9 8Du
int totalPage = 0; W];dD$Oqg
m_l[MG\
if(totalRecords % everyPage == 0) 4H-'Dr=G
totalPage = totalRecords / everyPage; ;'Nd~:-]
else QwJyY{O`
totalPage = totalRecords / everyPage + 1 ; d M-%{
4{l,
return totalPage; 3t6LT
} 9I/N4sou
l \?c}7k
privatestaticboolean hasPrePage(int currentPage){ B+0hzkPY
return currentPage == 1 ? false : true; hG:|9Sol,
} j w9b)
\j)E5b+
privatestaticboolean hasNextPage(int currentPage, I9Fr5p-%O
9k~8
int totalPage){ n}77##+R&C
return currentPage == totalPage || totalPage == 2dzrRH
A= {UL
0 ? false : true; C/&-l{7
} ,=mS,r7
D )'bH5
TW>WHCAm
} $2el&I
;ZG\p TCA
65m"J'
^Q^_?~h*!
-o.:P>/
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。 W"3ph6[eW
"x /OIf
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 5P$4 =z91
Ip]KPrwp
做法如下: (%:c#;#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9<)NvU^-r
(Clkv
的信息,和一个结果集List: -B\HI*u
java代码: zkdetrR
:#~j:C|
PJ'E/C)i
/*Created on 2005-6-13*/ =6#Eh=7N
package com.adt.bo; %9RF
!#"zTj
import java.util.List; =4!e&o
SC])?h-Fw
import org.flyware.util.page.Page; 9!DQ~k%
H]jhAf<h
/** vFK<J Sk!
* @author Joa j9OG\m
*/ bnLPlf
publicclass Result { 7(
2{'r
Y7[jqb1D
private Page page; -\n@%$M]G
P_#bow
private List content; l?^4!&Nm
@k/NY*+
/** g
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* The default constructor U~l$\c
*/ '!a'ZjYyi
public Result(){ d$AWu{y
super(); )D82N`c2\i
} .%C|+#&d
mS~kJy_-
/** ApXy=?fc
* The constructor using fields f8.gT49I
* G<^{&E+=
* @param page MO <3"@/,
* @param content NS6:yX,/
*/ AlW66YAuQ
public Result(Page page, List content){ Sa`Xf\
this.page = page; =+?7''{>
this.content = content; 9v!1V,`j"
} !GEJIefx_
e,XYVWY%
/** w~?~g<q
* @return Returns the content. xLZG:^(I
*/ ?_"ik[w}
publicList getContent(){ t\j*}# S
return content; E'.7xDN
} 3CGp`~Zf
a,#j =
/** B[?CbU
* @return Returns the page. Y,e B|
*/ Sw^u3
public Page getPage(){ ~PahoRS
return page; \qK&q
} ?vHU#
:+|Z@KB
/** [o5Hl^
* @param content Jl9k``r*
* The content to set. fku<,SV$O4
*/ 4^OY
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public void setContent(List content){ M b1sF
this.content = content; 5=?\1`e1[
} o"BoZsMk
WYYa/,{9.
/** "E?2xf|.
* @param page Hi`//y*92H
* The page to set. @)&=%
*/ n%s]30Xs
publicvoid setPage(Page page){ "?I y (*^
this.page = page;
2WVka
} h"lv7;B$
} Ev(>z-{F
'B0{_RaTb
e?=^;v%r
YgV817OV
1.9}_4!
2. 编写业务逻辑接口,并实现它(UserManager, 4l45N6"
6Yxh9*N~]
UserManagerImpl) YLE!m?
java代码: qF-@V25P
W=qVc
j578)!aJ
/*Created on 2005-7-15*/ {_Rr 6
package com.adt.service; s^uS1
M|`U"vO
import net.sf.hibernate.HibernateException; `LE6jp3,
//<nr\oP
import org.flyware.util.page.Page; j*jo@N|
}\:NuTf
import com.adt.bo.Result; G&V/Gj8
iBgx
/** > eIP.,9
* @author Joa zSja/yq
*/ 1gy.8i
publicinterface UserManager { &&:YVd
!~D}/Q;#}\
public Result listUser(Page page)throws ,+{LYF
Pjjewy1}^
HibernateException; i,4>0o?
lun\`f 5Q
} M={V|H0
<drODjB
8tFoN*M
EbE-}>7OO
MgrLSKLT
java代码: m6CI{Sa](l
@A89eZbW
<\ :Yk
/*Created on 2005-7-15*/ gPsi
package com.adt.service.impl; (l-ab2'
UsQ+`\|
import java.util.List; H'HA+q
q$tUH)0
import net.sf.hibernate.HibernateException; 9"A`sGZ
?Yk.$90
import org.flyware.util.page.Page; =4PV;>X
import org.flyware.util.page.PageUtil; ?D*/*Gk{
j=aI9p
import com.adt.bo.Result; DLMM/WJg@
import com.adt.dao.UserDAO; uIZ -#q
import com.adt.exception.ObjectNotFoundException; >kp?vK;'B
import com.adt.service.UserManager; \GZM&Zd
Ksj -zR;
/** z'\_jaj^
* @author Joa Slher0.Y
*/ \BZhf?9U
publicclass UserManagerImpl implements UserManager { SY^t} A7:/
7KL v6]b
private UserDAO userDAO; kDN:ep{/
,>-< (Qi
/** g/+C@_&m
* @param userDAO The userDAO to set. 4^~(Mh- Mw
*/ OFv%B/O
publicvoid setUserDAO(UserDAO userDAO){ TQ*1L:X7M&
this.userDAO = userDAO; ^_u kLzP9
} /1Q(b
\6<=$vD
/* (non-Javadoc) M
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* @see com.adt.service.UserManager#listUser bc)~k:
xt%7@/hiE
(org.flyware.util.page.Page) L3 --r
*/ l6kWQpV
public Result listUser(Page page)throws aV?@s4
~ZEmULKkR
HibernateException, ObjectNotFoundException { Q[pV!CH
int totalRecords = userDAO.getUserCount(); /bi[e9R
if(totalRecords == 0) \LppYXz
throw new ObjectNotFoundException Q/_f
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("userNotExist"); x+x40!+\
page = PageUtil.createPage(page, totalRecords); HO%wHiv1X
List users = userDAO.getUserByPage(page); [uq$5u
returnnew Result(page, users); ?$^2Umt0
} xScLVt<\e
yXF?H"h(
} zN@}
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0F|AA"mMT
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~ZhraSI)G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hKjt'N:~ZY
s6zNV4
询,接下来编写UserDAO的代码: `_{`l4i5
3. UserDAO 和 UserDAOImpl: -VTkG]{`Ir
java代码: 'BPp ]R#{
7MHKeLq
V=V:SlS9|
/*Created on 2005-7-15*/ M&Uj^K1
package com.adt.dao; 3]UUG
RUT,Y4 b
import java.util.List; FPI;Jx6W'
7C ,UDp|
import org.flyware.util.page.Page; .wu
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import net.sf.hibernate.HibernateException; ?zVL;gVWA
f[~L?B;_L
/** ;)e2@'Agl
* @author Joa D-(w_$#
*/ o=?C&f{
publicinterface UserDAO extends BaseDAO { 5HO9+i
h!ZV8yMc
publicList getUserByName(String name)throws rKf-+6Na
yA(K=?sq
HibernateException; kO{s^_qR^c
,@3$X=),E
publicint getUserCount()throws HibernateException; [tA;l+Q\&
^__Dd)(
publicList getUserByPage(Page page)throws ;R?I4}O#R8
%V{7DA&C
HibernateException; cwWodPNm
2e9es
} fKeT~z{~
q**G(}K
D]~MC
ANSFdc
KiOcu=F
java代码: :WL'cJ9a
me ks
RcF
mP P`xL?T
/*Created on 2005-7-15*/ p>;_e(
package com.adt.dao.impl; `zXO_@C
#ap9Yoyk\
import java.util.List; WT`4s
D{4YxR
PX
import org.flyware.util.page.Page; [$"n^5_~
pV,P|>YTf
import net.sf.hibernate.HibernateException; GJp85B!PlO
import net.sf.hibernate.Query; qfz 8jY]
P(73!DT+
import com.adt.dao.UserDAO; oK%K}{`
hcbv;[bG
/** V6#K2
* @author Joa S'B|>!z@
*/ Xo*%/0q'
public class UserDAOImpl extends BaseDAOHibernateImpl dwd:6.J(
mJ`A_0
implements UserDAO { {aJJ`t
>Ll$p0W
/* (non-Javadoc) @wC5 g 4E
* @see com.adt.dao.UserDAO#getUserByName i'wAE:Xe
/'DsB%7g
(java.lang.String) YH_7=0EJ
*/ -!L"')
publicList getUserByName(String name)throws X'% ;B
Bk\Gj`"7
HibernateException { z,:a8LB#[
String querySentence = "FROM user in class njnDW~Snb
-7&Gi
+]
com.adt.po.User WHERE user.name=:name"; aKJQm'9Ks
Query query = getSession().createQuery R%
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(querySentence); NDAw{[.%
query.setParameter("name", name); #\ n8M
return query.list(); ,b;{emX h
} _#}n~}d
PF7&p~O(Z
/* (non-Javadoc) JA_BKA
* @see com.adt.dao.UserDAO#getUserCount() 4bJZmUb
*/ Mz;[ +p
publicint getUserCount()throws HibernateException { ]B]*/
int count = 0; ]$\|ktY!
String querySentence = "SELECT count(*) FROM 4[-*~C|W5
~~,rp) )
user in class com.adt.po.User"; yxq}QSb \3
Query query = getSession().createQuery `VL}.h
#I3$3^0i#
(querySentence); \7
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count = ((Integer)query.iterate().next ~/ilx#d
^F"iP7
()).intValue(); @*DyZB
return count; \y{Tn@7
} T=:]]nf?M
4r0b)Y&I
/* (non-Javadoc) Yl$SW;@
* @see com.adt.dao.UserDAO#getUserByPage g@Qgxsyk>
b(I2m
(org.flyware.util.page.Page) D^;*U[F?
*/ .*JA!B
publicList getUserByPage(Page page)throws F5qFYL;
AkT<2H|4
HibernateException { _:B1_rz7,
String querySentence = "FROM user in class rzI|?QaPi
5rV((
com.adt.po.User"; l?)ZJ3]a
Query query = getSession().createQuery 3QOUU,Dt$
a9?y`{%L
(querySentence); ?kz+R'
query.setFirstResult(page.getBeginIndex()) ^p/Ob'!
.setMaxResults(page.getEveryPage()); !!nuAQ"E[
return query.list(); h<\_XJJ
} 1uk0d`JL
3o|I[!2.
} ,mL
!(US
k%op>
&
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!;!~n`
b2b75}_A
至此,一个完整的分页程序完成。前台的只需要调用 +EM_TTf4
Y05P'Q
userManager.listUser(page)即可得到一个Page对象和结果集对象 }/,CbKi,+
on7I
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 ' 2-oh
OcSEo7W
webwork,甚至可以直接在配置文件中指定。 Q!FLR>8
#s%-INcR
下面给出一个webwork调用示例: %&\ jOq~
java代码: Lh-`OmO0>F
WmQ01v
)*d W=r/$V
/*Created on 2005-6-17*/ A;u" <KG?
package com.adt.action.user; 5]1h8PW!Y
pBC<u
import java.util.List; {A o,t+j
9lo[&^<
import org.apache.commons.logging.Log; 'snYu!`z
import org.apache.commons.logging.LogFactory; 2w$twW-
import org.flyware.util.page.Page; oiX"Lz{
HOp-P8z
import com.adt.bo.Result; *X38{rj
import com.adt.service.UserService; 2spg?]
import com.opensymphony.xwork.Action; =4 X]gW
Ij'NC C
/** 47T}0q,
* @author Joa ^-M^gYBR
*/ ._96*r=o
publicclass ListUser implementsAction{ m2Uc>S
3?s ?XAh
privatestaticfinal Log logger = LogFactory.getLog Bfv.$u00p
+/+P\O
(ListUser.class); D=)f
)-u'
T/P7F\R
private UserService userService; d'9:$!oz
9><mp]E4
private Page page; r
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xDO7A5
privateList users; gX?n4Csy'
9%iFV
N'
/* d=]U_+
* (non-Javadoc) s
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* ^aRgMuU
* @see com.opensymphony.xwork.Action#execute() ~ekh1^evu
*/ vY*\R0/a
publicString execute()throwsException{ Yp4c'Zk
Result result = userService.listUser(page); *V;3~x!
page = result.getPage(); gK3Mms]}m
users = result.getContent(); xqHL+W
return SUCCESS; ; W7Y2Md
} s-VSH
fH8!YQG8$
/** &VWlt2-R0h
* @return Returns the page. Ld|V^9h1;
*/ ~L+]n0*
public Page getPage(){ ^Dx#7bsDZR
return page; 4rU!4l
} 4o9$bv
I2HT2c$
/** |&hU=J
o
* @return Returns the users. ?Cci:Lin
*/ O(OmGu4%
publicList getUsers(){ n!N\zx8
return users; (3EUy"z-
} M'1HA
:nQp.N*p
/** RFG$X-.e
* @param page qvLDfN
* The page to set. C 7nKk/r
*/ !g0cC.'
publicvoid setPage(Page page){ XSB8z
this.page = page; ?(im+2
} iY.eJlfH
KC&`x|
/** +|C[-W7Sw
* @param users :J(sXKr[C
* The users to set. @PcCiGZ
*/ nJVp.*S
publicvoid setUsers(List users){ {(vOt '
this.users = users; ,{j4
} GzdgL"M[
.T3=Eq&"W
/** Z%v6xP.
* @param userService jFj~]]j
* The userService to set. f:%SW
*/ mpef]9
publicvoid setUserService(UserService userService){ T#iU+)-\%
this.userService = userService; &
QY#3yj=
} ]R Mb,hJ
} qiNliJ>40E
\mXqak,y
}h~'AM
/=
^L
iP
xtJAMo>g
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, _IYY08&(r
t>U!Zal"
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 gEKO128
qB JRS'6'9
么只需要: XU#,Bu{
java代码:
kQ }s/*
+?e}<#vd'?
&LU'.jY
<?xml version="1.0"?> jpO38H0)
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork XZ:1!;
9oq)X[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5V|tXsy:
*j<@yG2\gP
1.0.dtd"> g[!Cj,
gNa#|
<xwork>
hh&Js'd
&N{zkMf
<package name="user" extends="webwork- %\yK5V5
0QR.
interceptors"> Jn,w)Els
~.Q4c*_b
<!-- The default interceptor stack name h3h8lt_|
P{lh)m>
--> j<$R4A1
<default-interceptor-ref f8!l7{2%q
sfC@*Y2XT
name="myDefaultWebStack"/> ;Prg'R[o;
2k3 z'RLG
<action name="listUser" FR' b`Xv:
s,
-*q}
class="com.adt.action.user.ListUser"> EVSK8T,
<param |!5@xs*T
4qBY%1
name="page.everyPage">10</param> Ai jUs*n 2
<result :bw6 k
3"B+xbe=
name="success">/user/user_list.jsp</result> +UaO<L
</action> dP3VJ3+
%
t~~r-V":
</package> kGj]i@(PA4
td/5Bmj
</xwork> nCB[4
36i_D6
]n1D1
7xR|_+%~K
x9\J1\
J=L`]XE
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 GG>Y/;^
A[RN-R,
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。 eH
`t \n
%o-jwr}O{
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 T`mEO\f
7 FIFSt
6)+9G_
&"O_wd[+:
4I1K vN<A
我写的一个用于分页的类,用了泛型了,hoho Znq(R8BMW
)x9]xqoR
java代码: iDR6?f P
oP,RlR
Ebbe=4
package com.intokr.util; ]kH}lr
yG
\y,;Cfl<
import java.util.List; i/M+t~
"9u-lcQ\
/** 67,3i~
* 用于分页的类<br> m^c%]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> KY8^BjY@
* Lo5Jb6nm
* @version 0.01 ~W/}:;
* @author cheng Bx%=EN5.
*/ eAU"fu6d
public class Paginator<E> { ev*c4^z:s
privateint count = 0; // 总记录数 g)nXo:)&