Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [4e5(!e
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 k~ue^^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 kz^G.5n
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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 %*nZ,r
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分页支持类: 4KnDXQ%
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java代码: rpmDr7G
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package com.javaeye.common.util; SH.'E Hd
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import java.util.List; 8Yh2K}
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publicclass PaginationSupport { JSU\Hh!
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; S SXSgp
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privateList items; :w+Rs+R
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privateint totalCount; x3Uv&
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privateint[] indexes = newint[0]; H =jnCGk
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privateint startIndex = 0; z0sB*5VH
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public PaginationSupport(List items, int xcig'4L
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totalCount){ fVM%.`
setPageSize(PAGESIZE);
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setTotalCount(totalCount); XHr{\/4V
setItems(items); :$j~;)2
setStartIndex(0); *u}):8=&R
} ^4"_I
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public PaginationSupport(List items, int EB#z\
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totalCount, int startIndex){ 7@F B^[H:y
setPageSize(PAGESIZE); vF,l?cU~
setTotalCount(totalCount); ( nh!tC
setItems(items); A SSoKrFL
setStartIndex(startIndex); RC 48e._t
} ~&x%;cnv_
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public PaginationSupport(List items, int
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totalCount, int pageSize, int startIndex){ Fv9Z'#t
setPageSize(pageSize); 'Khq!pC
setTotalCount(totalCount); 9\8""-
setItems(items); ,>$#e1!J
setStartIndex(startIndex); Nd6z81
}
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publicList getItems(){ NQAnvX;
return items; sCUPa-cHF
} gJ])A7O
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publicvoid setItems(List items){ p,Z6/e[SI
this.items = items; b Y>Ug{O;
}
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publicint getPageSize(){ JG[+e*8
return pageSize; 6voK{C4J
} o$-Phl
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publicvoid setPageSize(int pageSize){ ^.(]i\V_
this.pageSize = pageSize; "a: ;
} tT 7$2 9
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publicint getTotalCount(){ Bg`b*(Q
return totalCount; [V2l&ZUni
} H)S3/%.|
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publicvoid setTotalCount(int totalCount){ (/Ubw4unI
if(totalCount > 0){ g@QpqrT
this.totalCount = totalCount; c|7Pnx%gT
int count = totalCount / i`Tne3)
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pageSize; /Hx\ gtV
if(totalCount % pageSize > 0) U2aE:$oeYi
count++; `9ieTt
indexes = newint[count]; p})&Zl)V
for(int i = 0; i < count; i++){ 9qpH 8j+
indexes = pageSize * m[}$&i$(
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} $OT:J
}else{ H.9 J}k1S
this.totalCount = 0; gor6c3i
} ' 9,}N:p
} 8[DD=[&
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publicint[] getIndexes(){ !-QKh aY
return indexes; Rwr0$_A
} ,y0kzwPR1
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publicvoid setIndexes(int[] indexes){ gQ?k}D
this.indexes = indexes; y?rsfIth`
} s#Le`pGoW
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publicint getStartIndex(){ 0`x<sjG\q
return startIndex; ecHy. 7H
} ?eu=0|d
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publicvoid setStartIndex(int startIndex){ !O5UE
if(totalCount <= 0) .,c8cq?
this.startIndex = 0; ;7hf'k
elseif(startIndex >= totalCount) ! yxb<
this.startIndex = indexes a%AU9?/q#
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[indexes.length - 1]; :70oO}0m.
elseif(startIndex < 0) PH]q#/'
this.startIndex = 0; H`y- "L8q
else{ D1w_Vpz
this.startIndex = indexes :>,d$f^tqE
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[startIndex / pageSize]; +Kk6|+5u
}
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} 34oC285yc
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publicint getNextIndex(){ ,^+3AT
int nextIndex = getStartIndex() + g~cWBr%>
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pageSize; #[A/zH|xvV
if(nextIndex >= totalCount) |m=@;B|
return getStartIndex(); 6G(k{S
else iw#luHcJ
return nextIndex; I*#~@:4*
} pG"
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publicint getPreviousIndex(){ $)'{+1
int previousIndex = getStartIndex() - vOqYt42
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pageSize; GxvVh71zP
if(previousIndex < 0) @}FRiPo6
return0; S`J_}>
else BFMM6-Ve
return previousIndex;
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} E J 9A
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} v!x=fjr<
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抽象业务类 uU<Yf5
java代码: bk8IGhO|m!
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/** _z}d yp"I
* Created on 2005-7-12 IlaH,J7n
*/ ^ML2xh
package com.javaeye.common.business; 0^.q5#A2
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import java.io.Serializable; .M_;mhRI
import java.util.List; ~zuMX;[
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import org.hibernate.Criteria; o2jnmv~
import org.hibernate.HibernateException; K46mE
import org.hibernate.Session; QJv,@@mu
import org.hibernate.criterion.DetachedCriteria; B a Xzz
import org.hibernate.criterion.Projections; ^c=@2#^\
import \TKv3N
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org.springframework.orm.hibernate3.HibernateCallback; 'dx4L }d
import H\O|Y@uVr
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org.springframework.orm.hibernate3.support.HibernateDaoS V-jo2+Y5=
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upport; VB[R!S=
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import com.javaeye.common.util.PaginationSupport; Q,s,EooIx
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public abstract class AbstractManager extends QJ$]~)w?H
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HibernateDaoSupport { vK6bpzI
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privateboolean cacheQueries = false; (US8Sc
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privateString queryCacheRegion; +[cm
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publicvoid setCacheQueries(boolean SBYRN##n_
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cacheQueries){ bi,%QZZ
this.cacheQueries = cacheQueries; uH]^/'8vBd
} Y}4dW'
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publicvoid setQueryCacheRegion(String F9d][ P@@
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queryCacheRegion){ fA|'}(kH
this.queryCacheRegion = ^P]: etld9
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queryCacheRegion; FL` . (,
} Q(%uDUg%
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publicvoid save(finalObject entity){ J,E&Uz95%
getHibernateTemplate().save(entity); 2!jbaSH(+
} U:`rNHl
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publicvoid persist(finalObject entity){ #8[,w.X
getHibernateTemplate().save(entity); %,>,J`
} RI%*5lM8;
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publicvoid update(finalObject entity){ A@`C<O ^
getHibernateTemplate().update(entity); @GGyiK@
} d*H-l3N
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publicvoid delete(finalObject entity){ (spX3n%p
getHibernateTemplate().delete(entity); E{j6OX\
} /AWHG._
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publicObject load(finalClass entity, Q9rE_}Z
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finalSerializable id){ !N!M
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return getHibernateTemplate().load mV^dIm
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(entity, id); &npf
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} CNP?i(Rk
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publicObject get(finalClass entity, !CEF@J
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finalSerializable id){ $'e.bh
return getHibernateTemplate().get QO|ODW+D
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(entity, id); az`5{hK
} 15 SIZ:Q
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publicList findAll(finalClass entity){ \2~.r/`1
return getHibernateTemplate().find("from 's*UU:R
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" + entity.getName()); SqEO
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} QAu^]1 ;
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publicList findByNamedQuery(finalString 'X`\vTxB
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namedQuery){ uE/qraA
return getHibernateTemplate Gew0Y#/
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().findByNamedQuery(namedQuery); 6W3}6p
} .%D] z{''
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publicList findByNamedQuery(finalString query, !M}&dW2
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finalObject parameter){ =#1/<q)L
return getHibernateTemplate po{f*}gas]
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().findByNamedQuery(query, parameter); Z#\
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} #
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publicList findByNamedQuery(finalString query, n cihc$V<
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finalObject[] parameters){ vn|X,1o
return getHibernateTemplate pvcf_w`n
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().findByNamedQuery(query, parameters); {_ Wtk@
} ab
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publicList find(finalString query){ 6"gncB.
return getHibernateTemplate().find WukCE
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eq);
(query); ! a1j c_
} ]%NCKOM
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publicList find(finalString query, finalObject t+66kB N
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parameter){ egKYlfe"
return getHibernateTemplate().find 7rsrC
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(query, parameter); KA.@q AEB
} MJ>(HJY6?%
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public PaginationSupport findPageByCriteria EMJ}tvL0Tp
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(final DetachedCriteria detachedCriteria){ Vd|/]Zj
return findPageByCriteria -BNW\]}
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); vUj7rDT|
} !$Mv)c/_u
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public PaginationSupport findPageByCriteria w/Ia`Tx$
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(final DetachedCriteria detachedCriteria, finalint XMuZ'I
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startIndex){ 9/^4W.
return findPageByCriteria Ip?Ueaei
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(detachedCriteria, PaginationSupport.PAGESIZE, 'L= g(
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startIndex); >oLM2VJ
} c-`&e-~XKL
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public PaginationSupport findPageByCriteria >iaZGXje
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(final DetachedCriteria detachedCriteria, finalint VSM%<-iQ
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pageSize,
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finalint startIndex){ |1rBK.8
return(PaginationSupport) {:fyz#>>^
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getHibernateTemplate().execute(new HibernateCallback(){ G=\rlH]N
publicObject doInHibernate DlTV1X-^1
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(Session session)throws HibernateException { l--xq^,`o]
Criteria criteria = Z<xSU?J
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detachedCriteria.getExecutableCriteria(session); $eI[3{}X
int totalCount = H2rh$2
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((Integer) criteria.setProjection(Projections.rowCount {}vW=
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()).uniqueResult()).intValue(); wG19NX(
criteria.setProjection 4W$53LP8
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(null); %`%1W
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List items = 7dN]OUdi
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criteria.setFirstResult(startIndex).setMaxResults _MnMT9
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(pageSize).list(); Cl i k
PaginationSupport ps = '[:].?M
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new PaginationSupport(items, totalCount, pageSize, V?%>Ex$
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startIndex); J:pnmZ`X
return ps; >P+V!-%#
} x7t"@Gz
}, true); oa47TqFt
} Hya*7l']B
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public List findAllByCriteria(final Hm1C|Qb
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DetachedCriteria detachedCriteria){ '}LH,H:%G
return(List) getHibernateTemplate (w4#?_
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().execute(new HibernateCallback(){ E70
publicObject doInHibernate ]';!r20
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(Session session)throws HibernateException { 6 3Kec
Criteria criteria = Z
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detachedCriteria.getExecutableCriteria(session); Zo'lvOpyZ
return criteria.list(); ?RrJYj1
} ?9 2+(s
}, true); Y~gpi L3u
} K\=bpc"Fy
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public int getCountByCriteria(final eBtkTWx5[/
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DetachedCriteria detachedCriteria){ {ZN{$Ad3/
Integer count = (Integer) V|<qO-#.
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getHibernateTemplate().execute(new HibernateCallback(){ \>1M?
publicObject doInHibernate kMN z5P
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(Session session)throws HibernateException { `hI1
Criteria criteria = goWD~'\
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detachedCriteria.getExecutableCriteria(session); p;X[_h
return dax|4R
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criteria.setProjection(Projections.rowCount e Hd{'J<
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()).uniqueResult(); hTH"jAC+
} >-EoE;s
}, true); DlfXzKn;
return count.intValue(); W >;AMun
} nolTvqMT
} $(#o)r>_R
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用户在web层构造查询条件detachedCriteria,和可选的 .J&~u0g
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 //K]zu
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PaginationSupport的实例ps。 w[:5uo(
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ps.getItems()得到已分页好的结果集 tJ2l_M^
ps.getIndexes()得到分页索引的数组 69O?sIk
ps.getTotalCount()得到总结果数 2zArAch
ps.getStartIndex()当前分页索引 o NJ/AT
ps.getNextIndex()下一页索引 {RwwSqJ
ps.getPreviousIndex()上一页索引 S#2'Jw
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nLdI>c9R
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 r{p?aG
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一下代码重构了。 )1lYfJ
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我把原本我的做法也提供出来供大家讨论吧: &'T7 ~M:
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首先,为了实现分页查询,我封装了一个Page类: o6Vc}jRH
java代码: )<-kS
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/*Created on 2005-4-14*/ tv\P$|LV`8
package org.flyware.util.page; LW ntZ.
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/** B6OggJ9Iq
* @author Joa O#cXvv]Z*
* tdZ: w
*/ [4PG_k[uTJ
publicclass Page { vnXpC!1
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/** imply if the page has previous page */ mbJ#-^}V
privateboolean hasPrePage; mZMLDs:
j"}alS`-
/** imply if the page has next page */ AP/tBCeM
privateboolean hasNextPage; wjKW 3
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/** the number of every page */ CZ|Y o
privateint everyPage; &eK8v]|"W
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/** the total page number */ y4P mL
privateint totalPage; T"dWrtO
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/** the number of current page */ }w"laZ*
privateint currentPage; is#?O5:2
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/** the begin index of the records by the current %8hhk]m\b>
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query */ c1jgBty
privateint beginIndex; vseuk@>
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/** The default constructor */ Wa,[#H
public Page(){ $;$_N43
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} qo$<&'r
o )Ob}j
/** construct the page by everyPage `Z/"Dd;F^3
* @param everyPage 1mf|:2,
* */ )CihqsA2
public Page(int everyPage){ J}%&;uv
this.everyPage = everyPage; eX;"kO
} \CU.'|X
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/** The whole constructor */ 'OkF.bs
public Page(boolean hasPrePage, boolean hasNextPage,
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6
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int everyPage, int totalPage, ?ry`+nx
int currentPage, int beginIndex){ S(9fGh
this.hasPrePage = hasPrePage; ]e)<CE2
this.hasNextPage = hasNextPage; #}e)*(
this.everyPage = everyPage; ;Fp"]z!Qh+
this.totalPage = totalPage; C!~&c7
this.currentPage = currentPage; Y/)>\
this.beginIndex = beginIndex; Jr\4x7a;`~
} v=9:N/sW
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/** $+:_>n^#/
* @return FW=oP>f]w
* Returns the beginIndex. .* VZY
*/ .P-@ !Q5*
publicint getBeginIndex(){ b
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return beginIndex; "aAzG+NM
} 7lf*
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/** vY}/CBmg
* @param beginIndex ]?b#~
* The beginIndex to set. X;ijCZb3b
*/ 5wiU4-{
publicvoid setBeginIndex(int beginIndex){ <Cn-MOoM
this.beginIndex = beginIndex; NfDg=[FN[
} p>65(&N,
]NG`MZ
/** <_ddGg~
* @return @<AyCaU`.
* Returns the currentPage. *,@dt+H!y
*/ ] 6M- s
publicint getCurrentPage(){ kCLz@9>FQ
return currentPage; XQHvs{Po
} ^Shz[=fd
@ 5|F:J
/** ` *h-j/M
* @param currentPage rjx6Ad/\
* The currentPage to set. D]Bvjh
*/ /<
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publicvoid setCurrentPage(int currentPage){ |HhUU1!
this.currentPage = currentPage; h68sQd
} ;la(Q~#
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/** NFU 5+X-c
* @return MXSPD#gN
* Returns the everyPage. gKn"e|A
*/ 9.D'!
publicint getEveryPage(){ YYZE-{ %
return everyPage; cZ%weQa#N)
} =<n+AqJ%
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/** |*i0h`a
* @param everyPage GC~Tf rf=r
* The everyPage to set. $Rd74;edn
*/ *|a_(bQ4@
publicvoid setEveryPage(int everyPage){ -:AknQq
this.everyPage = everyPage; *<"xF'C
} pRc@0^G
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/** *:aJlvk
* @return aQ46euth
* Returns the hasNextPage. 3-Xum*)Y
*/ b jZcWYT
publicboolean getHasNextPage(){ G>d@lt
return hasNextPage; [#M^:Q
} ,*}SfCon
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/** )&;?|X+p
* @param hasNextPage 9JJ(KY
* The hasNextPage to set. =|
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*/ Jf YO|,
publicvoid setHasNextPage(boolean hasNextPage){ =K-B
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this.hasNextPage = hasNextPage; m9a(f >C
} Ca0~K42~
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/** -|"mB"Dc
* @return q}U^H
* Returns the hasPrePage. }{ J<Wzw
*/ R<a7TkL4?
publicboolean getHasPrePage(){ RxjC sjg
return hasPrePage; v<HhB.t.
} {^1D|y
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/** #\GWYWkR
* @param hasPrePage a=.A/;|0*
* The hasPrePage to set. "z1\I\
^
*/ GxuFO5wz
publicvoid setHasPrePage(boolean hasPrePage){ sFT-aLpL@V
this.hasPrePage = hasPrePage;
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} r**u=q%p
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/** OjCTTz
* @return Returns the totalPage. ^%VMp>s
* 4ac2^`
*/ FI`][&]V
publicint getTotalPage(){ \/xWsbG\
return totalPage; f-E]!\Pg
} Rs$k3
*&Np;^~
/** U^-:qT;CX
* @param totalPage 9r+]V=
* The totalPage to set. 3<88j&9
*/ KnaQhZ
publicvoid setTotalPage(int totalPage){ 1
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this.totalPage = totalPage; /EZF5_`bT
} MN}@EQvW==
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} }S\ \"SBC
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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 ,edX;`#
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个PageUtil,负责对Page对象进行构造: R^.E";/h
java代码: lfba
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/*Created on 2005-4-14*/ %5?qS`/c(
package org.flyware.util.page; "g;^R/sfq
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; A.8{LY;
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/** (RW02%`jjy
* @author Joa g
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* u(iEuF;7
*/ vPz$jeA
publicclass PageUtil { K;^$n>Y
];P$w.0
privatestaticfinal Log logger = LogFactory.getLog =+HMPV6yg7
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(PageUtil.class); z UN&L7D
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/** wQ]!Y?I
* Use the origin page to create a new page \X1?,gV_
* @param page xF![3~~3[
* @param totalRecords = m]|C1x
* @return }q7rR:g
*/ : $4
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publicstatic Page createPage(Page page, int 8@y@}
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totalRecords){ mux_S2x9m\
return createPage(page.getEveryPage(), Qa-]IKOs
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page.getCurrentPage(), totalRecords); ,v(K|P@
} I.#V/{J
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/** |&!04~s;E
* the basic page utils not including exception 3<">1] /,
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handler R{={7.As+
* @param everyPage t6m&+N
* @param currentPage G- nS0Kn:
* @param totalRecords 4L<h%
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* @return page mY!os91KoO
*/ CRXIVver
publicstatic Page createPage(int everyPage, int Y.FqWJP=p
v',%
currentPage, int totalRecords){ 6jS:_[p
everyPage = getEveryPage(everyPage); pgNyLgN
currentPage = getCurrentPage(currentPage); 4R<bfZ43
int beginIndex = getBeginIndex(everyPage, W`auQO
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currentPage); W:5,zFW
int totalPage = getTotalPage(everyPage, 0_\@!#-sml
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totalRecords); V!^5#A<
boolean hasNextPage = hasNextPage(currentPage, W#^W1j>_G
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totalPage); C|or2
boolean hasPrePage = hasPrePage(currentPage); #>[BSgW
.r=F'i}-j*
returnnew Page(hasPrePage, hasNextPage, _o,Mji|
everyPage, totalPage, 0 Z{;sW
currentPage, OH+kN/Fd
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beginIndex); YC,)t71l{
} .eZsKc-@
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privatestaticint getEveryPage(int everyPage){ ePD~SO9*
return everyPage == 0 ? 10 : everyPage; '+8`3['
} 4n}tDHvd
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privatestaticint getCurrentPage(int currentPage){ "CH3\O\
return currentPage == 0 ? 1 : currentPage; L_ &`
} ^}VAH#c
p h5rS<
privatestaticint getBeginIndex(int everyPage, int CN(}0/
@cc4]>4
currentPage){ CRpMpPi@}
return(currentPage - 1) * everyPage; +c+i~5B4
} j2dptM3t{
Wjf,AjL\
privatestaticint getTotalPage(int everyPage, int J/T$.*X
<r`^iR)%
totalRecords){ JSf \ApX
int totalPage = 0; B:?MMXB
; fOkR+
if(totalRecords % everyPage == 0) NA`qC.K
totalPage = totalRecords / everyPage; >)+-:
else 4ju=5D];
totalPage = totalRecords / everyPage + 1 ; ;kE|Vx
Gt|m;o
return totalPage; /RF=8,A
} _{k-&I
BSyl!>G6n8
privatestaticboolean hasPrePage(int currentPage){ sFrerv&0
return currentPage == 1 ? false : true; 78u9> H
} iCZuE:I1K,
@)^|U"
privatestaticboolean hasNextPage(int currentPage, p#QR^|7"
Vs"1:gi&
int totalPage){ AJJa<c+j
return currentPage == totalPage || totalPage == K6BP~@H_D
9|{t%F=-
0 ? false : true; f6$$e+
} 2d60o~E
Md5|j0#p
azCod1aL{
} cxig <W
ey/=\@[p
6eB2mcV
3ss0/\3P
3!*qB-d
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。 -(FhjIr
\r5L7y$9 h
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1Z_2s2`p
:|z.F+-/
做法如下: g)**)mz[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 C&/_mm5
ZQ)vvD<
的信息,和一个结果集List: PHh4ZFl]_I
java代码: %Mxc"% w
p?H2W-
cGUsao
/*Created on 2005-6-13*/ >V$
S\"
package com.adt.bo; 0qSf7"3f
LUfo@R
import java.util.List; GS@Zc2JPF
ClWxL#L6~
import org.flyware.util.page.Page; gnWEsA\!
G]k+0&X
/** 6Z>G%yK
* @author Joa `Re{j{~s
*/ dhCrcYn
publicclass Result { HU47S
(p!w`MSv
private Page page; ypy
=}OcMM`f
private List content; 3T)_(SM"
h}n?4B~Gi
/** ["~T)d'
* The default constructor 8}.V[,]6
*/ (/e[n.T
public Result(){ Lz:Q6
super(); N;|:Ks#!
} kVY0
E
*Kmo1>^
/** tpj6AMO/`d
* The constructor using fields ;4Wz0suf
* v"8i2+j
* @param page \]Y=*+{
* @param content Qk?J4 B
*/ n>L24rL
public Result(Page page, List content){ 3ahbv%y
this.page = page; 5}|bDJ$% _
this.content = content; ]wHXrB8vx
} 'XP
S '(K
/** 8o\KF(I
* @return Returns the content. <o"2z~gv
*/ T;1aL4w"
publicList getContent(){ ^EZ?wdL
return content; mXJ`t5v^l
} _`d=0l*8
%Y-KjSs+l
/** =`/GBT$
* @return Returns the page. ^CfWLL&
c
*/ !9]q+XefJ
public Page getPage(){ :P?zy| aBi
return page; V[^+lR
} !JnxNIr&i|
ewOe A|
/** W;^6=(&xn
* @param content #%{x*y:Ms
* The content to set. 01">$
*/ R&@NFin
public void setContent(List content){ 8!|LJI
this.content = content; !D~\uW1b
} /"
6Gh'
Nf1&UgX
/** C%q]o
* @param page 4O>0gK{w
* The page to set. Z,:}H6Mj9
*/ yo]8QO]97
publicvoid setPage(Page page){ (P|k$S?m
this.page = page; FKU)# Eo
} &.chqP(|
} 39oI
&D>8
`(&GLv[i^2
5D<"kT
+O?`uV
4cZlQ3OE.
2. 编写业务逻辑接口,并实现它(UserManager, ,ek0)z.
JXqwy^f
UserManagerImpl) -5u. Ix3
java代码: PD`EtkUnv
'da$i
@q <d^]po
/*Created on 2005-7-15*/ is6d:p
package com.adt.service; LR%P\~
]~kgsI[E
import net.sf.hibernate.HibernateException; ?(E?oJ)(
Y8Z-m (OQ
import org.flyware.util.page.Page; H5/w!y@
y;ymyy&
import com.adt.bo.Result; e?\34F
`XK#sCC
/** y2:Bv2}
* @author Joa Igb%bO_
*/ ^^kL.C Ym
publicinterface UserManager { Dy^A??A[E}
.v[!_bk8C
public Result listUser(Page page)throws (Z#j^}G_l
{9|S,<9
HibernateException; Q'c[yu
5Tiap8x+<
} 0khAi|PY
drd5oZ
U{PFeR,Uk
8c' 5P
)(W%Hmi
java代码: an,JV0
bw*D!mm,
~'t+X
/*Created on 2005-7-15*/ c'uDK>
package com.adt.service.impl; R7ExMJw
VNHt ]Ewj
import java.util.List; g]m}@b6(h
Mk|*=#e;
import net.sf.hibernate.HibernateException; yCZ[z
A
]6;oS-4gu?
import org.flyware.util.page.Page; ]Ag{#GJ5D
import org.flyware.util.page.PageUtil; (tzfyZ M
xG|n7w*
import com.adt.bo.Result; ^k4 n
import com.adt.dao.UserDAO; O+PRP"$g"
import com.adt.exception.ObjectNotFoundException; ?RU_SCp-
import com.adt.service.UserManager; yYPFk
g{^(EZ,
/** 4S*7*ak{
* @author Joa <c]?
*/ LhQidvCNJ
publicclass UserManagerImpl implements UserManager { 8rM1kOCf
@h)X3X
private UserDAO userDAO; j\TS:F^z
Lo
uYY:Q
/** Qvm[2mb
* @param userDAO The userDAO to set. ~RIa),GVX
*/ e<-^
publicvoid setUserDAO(UserDAO userDAO){ R~d{Yv
this.userDAO = userDAO; w_9[y
} +YnQOh%v0s
J%lEyU
/* (non-Javadoc) C:{&cIFrPe
* @see com.adt.service.UserManager#listUser &OP =O*B
HVaKy+RU
(org.flyware.util.page.Page) 6d%)MEM
*/ WkSv@Y,
public Result listUser(Page page)throws K?X
6@u|h
R\:t
73
HibernateException, ObjectNotFoundException { t2#zQ[~X!
int totalRecords = userDAO.getUserCount(); 3?-2~s3gp
if(totalRecords == 0) 8npjQ;%4>
throw new ObjectNotFoundException h f9yK6
QIu!o,B
("userNotExist"); %tZ[wwt
page = PageUtil.createPage(page, totalRecords); ;7bY>zc(w
List users = userDAO.getUserByPage(page); A\T9>z^k
returnnew Result(page, users); 7,,#f&jP
} ~_W>ND
Jec<1|
} 'Z`fZ5q
_VI3b$
~=9]M.$
)ioIn`g^-
fhbILg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;ksxz
8I%N^G
询,接下来编写UserDAO的代码: vH/Y]Am
3. UserDAO 和 UserDAOImpl: O*-sSf
java代码: ^=Egf?|[
:IX_}|
g].v
/*Created on 2005-7-15*/ .Af H>)E
package com.adt.dao; #Q$`3rr
|
sZu1K
import java.util.List; g0"KCX
-K U@0G
import org.flyware.util.page.Page; 8b:\@]g$
%LBT:Aw
import net.sf.hibernate.HibernateException; n^$HC=}S
egy#8U)Z
/** iYl$25k/1
* @author Joa P<s:dH"
*/ (h>+ivf|
publicinterface UserDAO extends BaseDAO { (]*!`(_b
2W q/_:
publicList getUserByName(String name)throws u}BN)%`B
hP26 Bb1
HibernateException; :j(D&?ao
Z=CY6Zu7
publicint getUserCount()throws HibernateException; C;.+ kE
S[L2vM)
publicList getUserByPage(Page page)throws d&5GkD.P
B)L;ja
HibernateException; Dd$CN&Ca
kU$M 8J.
} j aq/]I7
ljRR{HOl
NZ?| #53
.47tj`L
4Q
FX
java代码: .Wq"
~L=Idt!9
jj*e.t:F
/*Created on 2005-7-15*/ M}W};~V2ng
package com.adt.dao.impl; tx{tIw^2;
i=8){GX4
import java.util.List; `-[+(+["
LTt|"D
import org.flyware.util.page.Page; 1$adX
sKuPV
import net.sf.hibernate.HibernateException; 7{:g|dX
import net.sf.hibernate.Query; 5N4[hQrVJ
B^sHFc""V
import com.adt.dao.UserDAO; Zfn390 _
(VA:`pstP
/** 'P5|[du+
* @author Joa =| M[JPr
*/
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public class UserDAOImpl extends BaseDAOHibernateImpl ^7&0Pm
yyVv@
implements UserDAO { %Lwd1'C%
3O!TVSo
/* (non-Javadoc)
kN,WB
* @see com.adt.dao.UserDAO#getUserByName _Q3Ad>,U
W mT(>JBO
(java.lang.String) Z,bv D'u
*/ |`yzH$,F
publicList getUserByName(String name)throws ewb/Z[4
POCF T0R}
HibernateException { zO07X*Bw
String querySentence = "FROM user in class ;
(;J
o4g<[X)
com.adt.po.User WHERE user.name=:name"; Uv"GG:
K_
Query query = getSession().createQuery niIjatT
HJ,sZ4*]]
(querySentence); $S0eERga
query.setParameter("name", name); ooPH [p
return query.list(); 34P5[j!h
} !^*I?9P
<r{ )*]#l
/* (non-Javadoc) r`T(xJ!)
* @see com.adt.dao.UserDAO#getUserCount() ET7(n0*P}]
*/ 4? a!6
publicint getUserCount()throws HibernateException { wf8GH}2A
int count = 0; -O=a"G=
String querySentence = "SELECT count(*) FROM (iZE}qf7g
X@ Gm:6
user in class com.adt.po.User"; );.q:"
Query query = getSession().createQuery ;qF#!Kb5
6hs2B5)+
(querySentence); j!H\hj/]
count = ((Integer)query.iterate().next `y!6(xI
t"@:a
Y"
()).intValue(); _,M:"3;Z
return count; (mJqI)m8
} H.ZmLB
,~_)Cf#CB
/* (non-Javadoc) cn4CK.?
* @see com.adt.dao.UserDAO#getUserByPage G;%Pf9o26
6T_Mk0Sf+
(org.flyware.util.page.Page) l&d 6G0
*/ g(0
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publicList getUserByPage(Page page)throws $LF
=*YK6
HibernateException { K"sfN~@rT[
String querySentence = "FROM user in class n_n0Q}du
hC.7Z]
com.adt.po.User"; <E|K<}W#
Query query = getSession().createQuery bTn7$EG
L:y}
L
(querySentence); _r}oYs%1
query.setFirstResult(page.getBeginIndex()) )oSUhU26}
.setMaxResults(page.getEveryPage()); 3 9Ql|l$
return query.list(); X]Emz"
} nJ|8#U7
.wD>0Ig
} <~}t;ji
qG/a5i
t/bDDV"
VT\o=3_
nNIV(
至此,一个完整的分页程序完成。前台的只需要调用 _ID2yJ
Oifu ?f<r
userManager.listUser(page)即可得到一个Page对象和结果集对象 X"W%(x`w
'wAOY
的综合体,而传入的参数page对象则可以由前台传入,如果用 =$g8"[4
22|f!la8n
webwork,甚至可以直接在配置文件中指定。 ~7!J/LHg
pQxaT$
下面给出一个webwork调用示例: =De%]]>
java代码: g]V}azLr
1@Bq-2OD4
dy jzF`H
/*Created on 2005-6-17*/ W&]grG2/
package com.adt.action.user; Z3G>DF:$
<4y1[/S
import java.util.List; -0Q:0wU
0:**uion
import org.apache.commons.logging.Log; :XMw="u=
import org.apache.commons.logging.LogFactory; hltH{4
import org.flyware.util.page.Page; Lrz>0_Q
.BXZ\r`
import com.adt.bo.Result; 1V?}";T
import com.adt.service.UserService; !UD62yw~
import com.opensymphony.xwork.Action; zVs_|x="
Hi{c[;
/** )@3ce'
* @author Joa QJo)
*/ Xu$xO(
publicclass ListUser implementsAction{ #Xri%&~
ke~O+]
privatestaticfinal Log logger = LogFactory.getLog _y)#N<
J[UL
f7:
(ListUser.class); y'Xg"
+7o3TA]-
private UserService userService; w?.0r6j
8^zI
private Page page; qqSk*oH~
T IPb ]
privateList users; uG3t%CmN
d'Z|+lq:
/* Z\xR+3
* (non-Javadoc)
Nora<
* /MSz{ %v
* @see com.opensymphony.xwork.Action#execute() uj&^W[s
*/ A$W,#`E
publicString execute()throwsException{ !a3cEzs3
Result result = userService.listUser(page); ]}F_nc2L
page = result.getPage(); fk P@e3
users = result.getContent(); `6!l!8
v
return SUCCESS; ReP7c3D>p
} Qg?^%O'
3bpbk
/** )KR9al f3
* @return Returns the page. !5 %c`4
*/ _p7c<$;
public Page getPage(){ p[&'*"o!/
return page; PP&AF?C
} GFx>xQk
v 4(!~S
/** ro6peUL*2`
* @return Returns the users. ^MUtmzh
*/ Ol"p^sqwj
publicList getUsers(){ vN7a)s
return users; .0#?u1gXsX
} B4GgR,P@S
~tDV{ml
/** T eG5|`t],
* @param page 6{}]QvR
* The page to set. (ui"vLk8PP
*/ Z KnEg2a
publicvoid setPage(Page page){ eUVE8pZl
this.page = page; F)lDK.
} rjQV;kX>
hp,bfcM
/**
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* @param users G(|ki9^@"9
* The users to set. j,Qp*b#Qo
*/ 8@Xq ,J
publicvoid setUsers(List users){ KCDEMs}}zM
this.users = users; Gs.id^Sf
} FbJlyWND
+D`IcR-x
/** 6\g]Y
* @param userService
zfO0+fMH
* The userService to set. znFa4
*/ {?l#*XH;
publicvoid setUserService(UserService userService){ `*8p T
this.userService = userService; z`xdRe{QP
} ed2QGTgR
} ~DhYiOSo
uOs
8|pj,
Wze\z
CP'?Om2
br>"96A1l
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, E*.D_F
lzfaW-nu
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 zOCru2/
-JaC~v(0
么只需要: tV@!jaj\
java代码: Cz+>S3v M
7:R8QS9
yiSv#wD9
<?xml version="1.0"?> :u`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork \$V~kgQ0
z(aei(U=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- y0M^oLx
t@>Uc`%
1.0.dtd"> |OUr=b
&$qqF&
<xwork> @.a[2,o_
pqBd#
<package name="user" extends="webwork- d11~mU\
5K;jW
interceptors"> #<S+E7uTs
4E J
<!-- The default interceptor stack name nxKV7d@R
O2q`2L~
--> .4^Ep\\
<default-interceptor-ref cc*A/lD
%/CCh;N#
name="myDefaultWebStack"/> :xm,Ok
ga?.7F
<action name="listUser" >jME
== U0
ux& WN ,
class="com.adt.action.user.ListUser"> vp1IYW
<param weU'3nNN
A|I7R-
name="page.everyPage">10</param> T'
%TMA
<result |#L U"D
GP<A v1
name="success">/user/user_list.jsp</result> 9sFZs]uM
</action> G}&B{Ir
/z>G=kA
</package> ZC@ 33Q(
(2[tQ`~
</xwork> 1CU-^j
?V4?r2$c
(q59cA w~X
f6j;Y<}' g
UIi;&[
Q35$GFj"jD
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 Waj6.PCFm
X&8&NkH
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。 oa? bOm
<xKer<D
%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 3~;LNi
-uIu-a]
NBwxN
SS[jk
zp:kdN7!^
我写的一个用于分页的类,用了泛型了,hoho k(pI5N}pJZ
X+z!?W*a
java代码: P
hs4]!
&q^\*<B.^
@#hd8_)A.
package com.intokr.util; 7IB<0
WUm83"
import java.util.List; D>|m8-@]
lE=(6Q
/** yl/-!
* 用于分页的类<br> zRd^Uks
* 可以用于传递查询的结果也可以用于传送查询的参数<br> o|YY,G=C
* (/UW}$] h
* @version 0.01 Hm!ffqO_
* @author cheng :hr% 6K7
*/ dlmF?N|EC
public class Paginator<E> { y{
%2Q)
privateint count = 0; // 总记录数 u9ObFm$7
privateint p = 1; // 页编号 4{=zO(>
privateint num = 20; // 每页的记录数 l\xcR]O
privateList<E> results = null; // 结果 hOw
S.pL^Ru
/** {VtmQU?cJ
* 结果总数 epuN~T
*/ j*+[=X/
publicint getCount(){ Tw*:Vw
return count; Sio^FOTD
} 0tyoH3o/d
z SDRZ!
publicvoid setCount(int count){ v._Q XcE
this.count = count; e&sZ]{uD
} :,Z'/e0&
>-J%=P
/** XVr>\T4
* 本结果所在的页码,从1开始 QVLv}w`O
* z*n
* @return Returns the pageNo. Yef=HSzo
*/ %Xc50n2Z
publicint getP(){ sQUJ]h
return p; #JMww
} kDbDG,O
m}ZkNWH
/** E[q:65xl
* if(p<=0) p=1 E-gI'qG\(
* .'foS>W=t
* @param p tljZE)
*/ <LL+\kfTZO
publicvoid setP(int p){ p}H:t24Cr5
if(p <= 0) $WmB __
p = 1; (K9pr>le
this.p = p; \ OPJ*/U
} x-27rGN
&O8vI,M
/** riw0w
* 每页记录数量 aT|SKb`
*/ ]nPfIBoS
publicint getNum(){ :{sy2g/+
return num; >=Bl/0YH
} lw+Y_;
ASGV3r(
/** vd<r}3i*
* if(num<1) num=1 X!H[/b:1O
*/ @jh\yj rW
publicvoid setNum(int num){ ]JDKoA{S0
if(num < 1) <14,xYpE
num = 1; ^4MRG6G
this.num = num; Q/D?U[G
} TwPpZ@
D)shWJRlvW
/** wavyREK
* 获得总页数 a(.q=W
*/ &[
oW"Q{
publicint getPageNum(){ 1. A@5* Q
return(count - 1) / num + 1; efzS]1Jpz
} RJ}%pA4I
yM,.{m@F<
/** .-ihxEbzr
* 获得本页的开始编号,为 (p-1)*num+1 qmmQHS
*/ *<HA])D,
publicint getStart(){ eBT+|
return(p - 1) * num + 1; CgT5sk}
} _*iy *:(o
B:mtl?69g
/** BjX*Gm6l
* @return Returns the results. ,4W~CkLD
*/ %u=b_4K"j
publicList<E> getResults(){ xWRkg$A
return results; T-MC|>pv
} FYBW3y+AF&
0G;
b+
public void setResults(List<E> results){ gvzBV
+3'
this.results = results; vw~=z6Ka
} ~ eNKu
|)KOy~"
public String toString(){ V2B@Lq"9`
StringBuilder buff = new StringBuilder kB#;s
%*bGW'Cw
(); 3M^s
EaUI
buff.append("{"); D9yAq'k$
buff.append("count:").append(count); G^1 5V'*
buff.append(",p:").append(p); ZuLW%z.
buff.append(",nump:").append(num); ol3].0Vc]
buff.append(",results:").append =w !>/#U
9 AWFjoXl"
(results); pNFVa<D
buff.append("}"); DhVO}g)2#
return buff.toString(); q%S^3C&
} aHR+4m~)
6uS;H]nd<
} "J(T?|t
bVxbQ$
!kW~s_gUb*