Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 i'IT,jz!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 u` pTFy
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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 c+Q'4E0|
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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 dWAt#xII
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分页支持类: 8wU$kK
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java代码: h4Crq Yxa_
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package com.javaeye.common.util; $0])%
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import java.util.List; 3I6ocj[,
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publicclass PaginationSupport { s8h*nZ)v
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publicfinalstaticint PAGESIZE = 30; Aoe\\'O|V
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privateint pageSize = PAGESIZE; M0V<Ay\%O
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privateList items; ]aX@(3G1s
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privateint totalCount; Ak'=l;
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privateint[] indexes = newint[0]; {bj!]j
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privateint startIndex = 0; MIMC(<
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public PaginationSupport(List items, int X\^nV
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totalCount){ s68(jYC7[
setPageSize(PAGESIZE); dlu*s(O"
setTotalCount(totalCount); ?qh-#,O9B
setItems(items); "{q#)N
setStartIndex(0); #{i*9'
} waMF~#PJlt
}7 N6nZj`
public PaginationSupport(List items, int = Xgo}g1
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totalCount, int startIndex){ *z0!=>(
setPageSize(PAGESIZE);
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setTotalCount(totalCount); |T:R.=R$~
setItems(items); 8$( I! ;
setStartIndex(startIndex); Qqm?%7A1
} C}huU
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public PaginationSupport(List items, int LrU8!r`a
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totalCount, int pageSize, int startIndex){ T{dQ4
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setPageSize(pageSize); 0ho;L 0Nr'
setTotalCount(totalCount); U^m#!hp
setItems(items); [WwoGg*)mn
setStartIndex(startIndex); 'l*X?ccKy
} H& |/|\8F
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publicList getItems(){ pMfb(D"
return items; wQxI({k@
} 1@]&iZ]
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publicvoid setItems(List items){ vsGKCrLwh
this.items = items; Al>d
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} qBEp |V
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publicint getPageSize(){ +nYFLe
return pageSize; $xO8?
} U1\7Hcs$
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publicvoid setPageSize(int pageSize){ X[B P0:`t
this.pageSize = pageSize; R)NSJ-A!2
} !%>RHh[
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publicint getTotalCount(){ $1f2'_`8~
return totalCount; BgQEd@cN
} g'.OzD
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publicvoid setTotalCount(int totalCount){ E&U_1D9=L<
if(totalCount > 0){ EU[\D;
this.totalCount = totalCount; -WC0W
int count = totalCount / !XPjRd q
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pageSize; aODh5
if(totalCount % pageSize > 0) pz%s_g'
count++; Af3|l
indexes = newint[count]; TgiZ
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for(int i = 0; i < count; i++){ #U:|-
a.>
indexes = pageSize * ! M^O\C)
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} 5(>=};r+
}else{ ">}6i9o
this.totalCount = 0; /,\V}`Lx"
} -^_2{i
} /7}pReUj
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publicint[] getIndexes(){ (b25g!
return indexes; sN41Bz$q.
} *5)UIRd
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publicvoid setIndexes(int[] indexes){ \jfK']P/H
this.indexes = indexes; (/:m*x*6
} {JE [
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publicint getStartIndex(){ "6B@V=d
return startIndex; T^v763%
} A`7(i'i5]
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publicvoid setStartIndex(int startIndex){ J[ZHAnmPH
if(totalCount <= 0) :nx+(xgw
this.startIndex = 0; L
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elseif(startIndex >= totalCount) lV\iYX2#
this.startIndex = indexes 1K Vit{
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[indexes.length - 1]; 2Q6;SF"Z
elseif(startIndex < 0) L}h_\1
this.startIndex = 0; LG[N\%<!H
else{ .S//T/3O]Q
this.startIndex = indexes s"jvO>[
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[startIndex / pageSize]; M9iX_4
} #,#`<h!
} w6BBu0,KC
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publicint getNextIndex(){ xfRp_;l+R
int nextIndex = getStartIndex() + ^KhJBM /Z
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pageSize; wgFX')l:
if(nextIndex >= totalCount) DNGyEC
return getStartIndex(); O#)1zD}
else KA2>[x2
return nextIndex; 8pnD6Lp>
} 5,Fq:j)MxW
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publicint getPreviousIndex(){ (L(7)WbH
int previousIndex = getStartIndex() - OxHcoNrz
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pageSize; Bsa;,
if(previousIndex < 0) aE~T!h
return0; /a\i
else jg]KE8(
return previousIndex; h*Fv~j'p
} 5zK,(cF0-
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} . 1kB8&}
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抽象业务类 ,`f]mv l
java代码: cZVx4y%kz
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/** v]EMJm6d|
* Created on 2005-7-12 j|KDgI<0
*/ oJA_"xp
package com.javaeye.common.business; )0/9
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import java.io.Serializable; 0/v]YK.
import java.util.List; @&?(XY 'M%
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import org.hibernate.Criteria; .jJD$FC
import org.hibernate.HibernateException; sU>IETo
import org.hibernate.Session; ^BA
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import org.hibernate.criterion.DetachedCriteria; +zh\W9
import org.hibernate.criterion.Projections; '&cH,yc;b
import ao)';[%9s
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org.springframework.orm.hibernate3.HibernateCallback;
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import #LR4%}mg
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org.springframework.orm.hibernate3.support.HibernateDaoS CHGa_
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upport; #G#gc`S-,
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import com.javaeye.common.util.PaginationSupport; xf&[QG+Ef
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public abstract class AbstractManager extends w=#'8ZuU
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HibernateDaoSupport { [W3X$r~-
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privateboolean cacheQueries = false; vv.E6D^x(
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privateString queryCacheRegion; [gT}<W
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publicvoid setCacheQueries(boolean 0B(s+#s
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cacheQueries){ fG1iq<~
this.cacheQueries = cacheQueries; Z3&}C h
} wp@_4Iq1$
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publicvoid setQueryCacheRegion(String +ydd"`
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queryCacheRegion){ {dZ]+2Z~+
this.queryCacheRegion = ~B|m"qY{i
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queryCacheRegion; OjhX:{"59
} m\qeYI6, Z
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publicvoid save(finalObject entity){ HQ@g6
getHibernateTemplate().save(entity); 4Kch=jt4#
} [2-n*a(q
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publicvoid persist(finalObject entity){ P<IDb%W
getHibernateTemplate().save(entity); Qa,=
} G%sq;XT61
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publicvoid update(finalObject entity){ #][i!9$
getHibernateTemplate().update(entity); YVccO~!8
} /K|(O^nw
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publicvoid delete(finalObject entity){ di/QJrw
getHibernateTemplate().delete(entity); &jqylX
} @dv8 F
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publicObject load(finalClass entity, >eA@s}_8
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finalSerializable id){ ]mMJ6n
return getHibernateTemplate().load 9:p-F+
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(entity, id); <7]HM5h
} KAnV%j
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publicObject get(finalClass entity, ~5+RK16
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finalSerializable id){ y.lWyH9
return getHibernateTemplate().get |OJWQU![by
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(entity, id); Kn:Ml4[;
} n1PptR
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publicList findAll(finalClass entity){ l
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return getHibernateTemplate().find("from Nbr$G=U
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" + entity.getName()); o,WjM[e
} 9" q-Bb
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publicList findByNamedQuery(finalString ],SQD3~9
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namedQuery){ CFh9@Nx
return getHibernateTemplate jh oA6I
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().findByNamedQuery(namedQuery);
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} _f0AV;S:vd
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publicList findByNamedQuery(finalString query, %]Z4b;W[Y
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finalObject parameter){ U1r]e%df)
return getHibernateTemplate ~Fuq{e9`
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().findByNamedQuery(query, parameter); Mm$\j*f/
} jM\{*!7b
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publicList findByNamedQuery(finalString query, ]^C 8Oh<
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finalObject[] parameters){ yIL=jzm`7
return getHibernateTemplate cuN ]}=D
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().findByNamedQuery(query, parameters); JVuju$k
} nmU1xv_
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publicList find(finalString query){ {[2o
return getHibernateTemplate().find WrGA7&!+
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(query); i"G'#n~e
} ?z1v_Jh
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publicList find(finalString query, finalObject (j'\h/
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parameter){ !uGfS' Vl
return getHibernateTemplate().find Q7uJ9Y{X
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(query, parameter); nW)+-Wxq
} /i"hViCrlG
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public PaginationSupport findPageByCriteria e\C-a4[C8P
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(final DetachedCriteria detachedCriteria){ Z
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return findPageByCriteria V8/d27\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); zz*PAYl.
} [8Pt$5]^
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public PaginationSupport findPageByCriteria fc+-/!v
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(final DetachedCriteria detachedCriteria, finalint zhw*Bed<
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startIndex){ =R=V
return findPageByCriteria _BP%@o
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(detachedCriteria, PaginationSupport.PAGESIZE, #tR:W?!
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startIndex); ~3 :VM_
} 'u<e<hU
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public PaginationSupport findPageByCriteria U"7o;q
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(final DetachedCriteria detachedCriteria, finalint w80X~
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pageSize, YcA. Bn|as
finalint startIndex){ %k#+nad
return(PaginationSupport) b23A&1X
n 0=]C%wr
getHibernateTemplate().execute(new HibernateCallback(){ &|XgWZS5
publicObject doInHibernate ATkd# k%S
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(Session session)throws HibernateException { X)!XR/?
Criteria criteria = 4<($ZN8
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detachedCriteria.getExecutableCriteria(session); ~
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int totalCount = <~dfp
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((Integer) criteria.setProjection(Projections.rowCount -
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()).uniqueResult()).intValue(); SPV+ O{
criteria.setProjection PaSwfjOnqr
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(null);
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List items = 4dbX!0u1l
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criteria.setFirstResult(startIndex).setMaxResults tCrEcjT-
0Ye/
(pageSize).list(); 0hoMf=bb$
PaginationSupport ps = d`=
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new PaginationSupport(items, totalCount, pageSize, C)U4Fr ?E:
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startIndex); sR/Yv
return ps; ""7H;I&
} e&x)g;bn
}, true); <ci(5M
} 7;p/S#P:
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public List findAllByCriteria(final cgG*7E
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DetachedCriteria detachedCriteria){ fcdXj_u
return(List) getHibernateTemplate G
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}`L;.9
().execute(new HibernateCallback(){ = -oP,$k
publicObject doInHibernate yr},pB
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(Session session)throws HibernateException { m u9,vH
Criteria criteria = fL|9/sojz
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detachedCriteria.getExecutableCriteria(session); O h
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return criteria.list(); (.$$U3\
} 5{yg
}, true); }$<v
} Z><+4
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public int getCountByCriteria(final #fF5O2E'3
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DetachedCriteria detachedCriteria){ y"H5>
Integer count = (Integer) .*N,x(V
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getHibernateTemplate().execute(new HibernateCallback(){ =EVB?k
,
publicObject doInHibernate OF*E1BM
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(Session session)throws HibernateException { R7IFlQH%
Criteria criteria = s[7$%|~W
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detachedCriteria.getExecutableCriteria(session); IsT}T}p,t
return Uhvy2}w
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criteria.setProjection(Projections.rowCount >0SG]er@
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()).uniqueResult(); 2.nT k
} |m\7/&@<
}, true); lFuW8G,-f@
return count.intValue(); k@fxs]Y_L
} )r"R
} Z<|x6%
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用户在web层构造查询条件detachedCriteria,和可选的 Ox
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Y|mtQE?c
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PaginationSupport的实例ps。 %l%ad-V
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ps.getItems()得到已分页好的结果集 Eva&FHRTY
ps.getIndexes()得到分页索引的数组 Z wKX$(n
ps.getTotalCount()得到总结果数 nd\$Y
ps.getStartIndex()当前分页索引 &iD&C>;pf
ps.getNextIndex()下一页索引 6a9:P@tY
ps.getPreviousIndex()上一页索引 }cUO+)!Y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 pbh>RS=ri
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 DIYR8l}x
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一下代码重构了。 vx$DKQK@l\
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我把原本我的做法也提供出来供大家讨论吧: nCV7(ldmH
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首先,为了实现分页查询,我封装了一个Page类: -m,Y6
java代码: j7Zv"Vq@
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/*Created on 2005-4-14*/ ?1|\(W#
package org.flyware.util.page; g9Dynm5
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/** Ta3* G
* @author Joa Yx66Xy
* o=![+g
*/ q(46v`u
publicclass Page { D
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/** imply if the page has previous page */ ,ZYPffu<*
privateboolean hasPrePage; }] 1C=~lC
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/** imply if the page has next page */ |BtFT
privateboolean hasNextPage; jc32s}/H
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/** the number of every page */ K{Nj-Rqd
privateint everyPage; "J&WH~8+N
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/** the total page number */ N3Q
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privateint totalPage; Z>/
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/** the number of current page */ ]"O*&
privateint currentPage; ]2&RN@
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/** the begin index of the records by the current Z" l].\=
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query */ zk@s#_3ct
privateint beginIndex; x!7!)]h
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/** The default constructor */ #
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public Page(){ Q"!GdKM
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} `.~*pT*u
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/** construct the page by everyPage K4RQ{fWpm
* @param everyPage 00>knCe6
* */ aU.!+e%_
public Page(int everyPage){ EpT^r8I
this.everyPage = everyPage; 8B "^}y\0
} &\ad.O/Q
@tRDKPh
/** The whole constructor */ 3C;;z
public Page(boolean hasPrePage, boolean hasNextPage, 6xr%xk2E
z t
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int everyPage, int totalPage, 2H] 7 =j
int currentPage, int beginIndex){ -U7,~z
this.hasPrePage = hasPrePage; |rgPHRX^Hn
this.hasNextPage = hasNextPage; PgP\v -.
this.everyPage = everyPage;
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this.totalPage = totalPage; AnE]
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this.currentPage = currentPage; @d0~'_vtB
this.beginIndex = beginIndex; oOLj?
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} [T3%Xt'4
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/** =RM]/O9
* @return IQ$ 6}.
* Returns the beginIndex. wZ`*C
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*/
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publicint getBeginIndex(){ d&ff1(j(
return beginIndex; [_KOU2
} V~-tp^
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/** R9K~b^`
* @param beginIndex Y!ypG-
* The beginIndex to set. 2PNe~9)*#
*/ {g4w[F!77
publicvoid setBeginIndex(int beginIndex){ y\:Ma7V
this.beginIndex = beginIndex; ^FTS'/Q
} pz{ ]O_px
&:}WfY!hX
/** J9J/3O
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* @return x lsAct:
* Returns the currentPage. I2)2'j,B
*/ ~?iQnQYI
publicint getCurrentPage(){ F{
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return currentPage; G~4G$YL*
} M D&7k,!
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/** wT,=C'
* @param currentPage va"bw!zXo*
* The currentPage to set. 9@nd>B
*/ * vqUOh
publicvoid setCurrentPage(int currentPage){ l?xd3Z@7[
this.currentPage = currentPage; Bq-}BN?pz
} V8pZr+AJ
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/** Z(LTHAbBk|
* @return <<Z, 1{3F
* Returns the everyPage. >$a;+v
*/ g<$2#c}
publicint getEveryPage(){ ?1LRR
;-x
return everyPage; ^q|W@uG-(
} HHs!6`R$0c
e;|$nw-
/** &2ty++gC
* @param everyPage CHCT
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* The everyPage to set. {([`[7B>a<
*/ <33,0."K
publicvoid setEveryPage(int everyPage){ mO8/eVws[M
this.everyPage = everyPage; /*M3Ns1@2
} Z@>kqJ%
s+=':Gcb(C
/** p3T:Y_
* @return rJRg4Rog
* Returns the hasNextPage. ##alzC
*/ v}IhO~`uEq
publicboolean getHasNextPage(){ Otf{)f
return hasNextPage; s5*HS3D
} D O||o&u
2,|;qFJY-@
/** ID{XZ
* @param hasNextPage "-rqL
* The hasNextPage to set. H_aG\
*/ .2ZFJ.Z"
publicvoid setHasNextPage(boolean hasNextPage){ H9!q)qlK
this.hasNextPage = hasNextPage; OpK_?XG
} (zk/>Ou
ovi^bNQ
/** |goK@<
* @return % w
* Returns the hasPrePage. Fw}|c
*/ <zAYq=IU
publicboolean getHasPrePage(){ ~zWLqnS}
return hasPrePage; MGre_=Dm_
} YPCitGBl
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/** NBLjBa%eL
* @param hasPrePage -YrMVoZl
* The hasPrePage to set. !E)|[:$XT
*/ f=S2O_Ee
publicvoid setHasPrePage(boolean hasPrePage){ Imq-5To#
this.hasPrePage = hasPrePage; &rl;+QS
} roBb8M|q
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/** @S>;t)\J
* @return Returns the totalPage. Ap4.c8f?Q-
* $~%h4
*/ MpIiHKQ
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publicint getTotalPage(){ P|C5k5
return totalPage; 1083p9Uh
} ovDPnf(
sc6NON#
/** Hk(=_[S
* @param totalPage :)&vf<JL
* The totalPage to set. ooC9a>X
*/ A(cR/$fn6
publicvoid setTotalPage(int totalPage){ JZ&_1~Z=
this.totalPage = totalPage; aeAx0yE[p
} cL~YQJYp
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} .*.eY?,V
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m
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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 1-&L-c.
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个PageUtil,负责对Page对象进行构造: j['B9vG
java代码: Z_Y'#5o#
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*JQ*$$5
/*Created on 2005-4-14*/ 1X9s\JKQ
package org.flyware.util.page; l"jYY3N|h
(mKH,r
import org.apache.commons.logging.Log; ;K%/sIIke
import org.apache.commons.logging.LogFactory; gU NWM^n
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/** $em'H,*b3
* @author Joa KC9e{
* bMNr +N
*/ DH.UJ+
publicclass PageUtil { ItZYOt|Hn
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privatestaticfinal Log logger = LogFactory.getLog bSz7?NAp
qd#7A ksm
(PageUtil.class); nAAv42j[
;[(d=6{hc]
/** a(ITv roM/
* Use the origin page to create a new page \<09.q<8
* @param page H\\FAOj
* @param totalRecords -5ZmIlL.S
* @return .>P:{''
*/ Ym!e}`A\F
publicstatic Page createPage(Page page, int SW'eTG
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totalRecords){ XoL DqN!
return createPage(page.getEveryPage(), I~@8SSO,vH
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page.getCurrentPage(), totalRecords); gq/Za/!6
} b78~{ht`
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/** xIC@$GP
* the basic page utils not including exception h:r?:C>n
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handler %Ta"H3ZW
* @param everyPage x\f~Gtt7Y
* @param currentPage Gn_DIFa
* @param totalRecords rD a{Ve
* @return page &
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*/ js@L%1r#L
publicstatic Page createPage(int everyPage, int 4KnBb_w
zB~< @
currentPage, int totalRecords){ Y:t?W
everyPage = getEveryPage(everyPage); :zLf~W
currentPage = getCurrentPage(currentPage); WvSm!W
int beginIndex = getBeginIndex(everyPage, 9OW8/H&!
+F2OPIanT~
currentPage); .g\Oj0Cbxh
int totalPage = getTotalPage(everyPage, K,,) FM
LdN[N^n[H
totalRecords); k0K$OX*:e
boolean hasNextPage = hasNextPage(currentPage, p'1/J:EnV
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totalPage); 0doJF@H
boolean hasPrePage = hasPrePage(currentPage); UeLO `Ug0;
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returnnew Page(hasPrePage, hasNextPage, /lu|FWbEw
everyPage, totalPage, %Uz\P|6PO
currentPage, kP ,8[r
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beginIndex); a%`%("g!
} FiUwy/,ZV
!*NDsC9
privatestaticint getEveryPage(int everyPage){ /UK]lP^w]!
return everyPage == 0 ? 10 : everyPage; C&MqH.K
} dS4z Oz"
ipbhjK$
privatestaticint getCurrentPage(int currentPage){ z[v4(pO6
return currentPage == 0 ? 1 : currentPage; ^MF 2Q+
} L\:m)g,F.
Ez5t)l-
privatestaticint getBeginIndex(int everyPage, int >(S)aug$1
D5snaGss9a
currentPage){ '5De1K.\`
return(currentPage - 1) * everyPage; Q47R`"
} J
3C^tV
RO,TNS~
privatestaticint getTotalPage(int everyPage, int 7Y(Dg`8G
\&;y:4&l8
totalRecords){ jTIG#J)
int totalPage = 0; ~$5XiY8A
*qy \%A
if(totalRecords % everyPage == 0) Hy&Z0W'l
totalPage = totalRecords / everyPage;
Y6VJr+Ap(
else 4^l 9d
totalPage = totalRecords / everyPage + 1 ; 4oiE@y&{4
`cXLa=B)9
return totalPage; >RkaFcq
} t~/:St
": M]3.
privatestaticboolean hasPrePage(int currentPage){ pF-_yyQ
return currentPage == 1 ? false : true; rSJ!vQo
Cb
} t:fz%IOe
fJc(
privatestaticboolean hasNextPage(int currentPage, u@ #%SX
aq}hlA(w
int totalPage){ uH%b rbrU
return currentPage == totalPage || totalPage == PR:B6 F8
A+* lV*@0
0 ? false : true; Mh-"B([Z
} Sl,DZ!
jc
Mn
o?>0WSLlm
} ]$r]GVeN}H
yVmp,""a
j;]I
-M[
!~~KM?g
RdWn =;
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。 \EVT*v=}/
x,25ROaHY
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 ~^Cx->l
-@"3`uv"
做法如下: [+dCA
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =JzzrM|V*
E4892B:`
的信息,和一个结果集List: ?96r7C|
java代码: ~&D
=;M/
`mz}D76~#
K9%rr_ja!
/*Created on 2005-6-13*/ 04Zdg:[3-!
package com.adt.bo; rCDt9o>
]?@ [Ny=0
import java.util.List; Y:TfD{Xgc
QjY}$
import org.flyware.util.page.Page; 7CH&n4v
KJec/qca
/** cLf90|YFp
* @author Joa L{%L*z9J
*/ FXJ0
G>F
publicclass Result { 6LCtWX
+d\o|}c
private Page page; 6GunEYK!N8
-^m?%_<50l
private List content; xn2 nh@;
@e3+Gs
/** IdAh)#)
7
* The default constructor D r(0w{5
*/ u'l4=e
public Result(){ ojnO69v
super(); &@oI/i&0B
} ]j>xQm\
YFm%W@
/** oqF?9<Vgc,
* The constructor using fields % akW43cE
* GuR^L@+ -.
* @param page U?Jk
* @param content Gkuqe3
*/ e7;7TrB.
public Result(Page page, List content){ lu"0\}7X
this.page = page; .>R`#@+I
this.content = content; 1cOR?=G~
} aH1CX<3)~
z)C/U
/** i6_}
* @return Returns the content. Ct)58f2
*/ "D.<~!
publicList getContent(){ SzMh
return content; ]Wkgpfd56
} RQ8d1US
yR>P
/** j_so s%-
* @return Returns the page. 62R";# K
*/ ,:(s=JN+
public Page getPage(){ N=1ue`i
return page; ZEI)U,
I.
} C5dM`_3L
c%pf,sm'
/** i0{\c}r:4b
* @param content
aO<7a
6
* The content to set. 8C*@d_=q
*/ .ifz9jM'
public void setContent(List content){ &B(z**+9
this.content = content; "
7^nRJy
} p\=T#lb
*xNc^&.
/** wx3_?8z/O
* @param page <K^a2 D
* The page to set. ' J@J$#6
*/ >(a35 b$
publicvoid setPage(Page page){ LhLAQ2~
this.page = page; ; H ;h[
} /lC# !$9vz
} _rYW|*cIF
h-ii-c?R@0
r!Dk_|Cd
8C3oi&av/{
-yqgs>R(d
2. 编写业务逻辑接口,并实现它(UserManager, gEk;Tj
c@[Trk m
UserManagerImpl) ?.`
ga*
java代码: I zTJ7E*i
DK?aFSf\
(o|bst][S
/*Created on 2005-7-15*/ 2@tnOs(*
package com.adt.service; 9k;,WU(K<
aU(.LC
import net.sf.hibernate.HibernateException; nu\AEFT
gJ|#xZ
import org.flyware.util.page.Page; %.=}v7&<z
3*</vo#`
import com.adt.bo.Result; C+**!uYIB
]F+|C
/** Ps@']]4>W
* @author Joa c0Ih$z
*/ $}su'EIo
publicinterface UserManager { o+.L@3RT4
{FFdMdxy-
public Result listUser(Page page)throws MBt\"b#t
&'fER-
HibernateException; (/I6Wa
L/jaUt[,
} ExtC\(X;
%mmV#vwp
.hx(9
gV.? Myy
^o5;><S]
java代码: rB".!b
w|&lRo@1
i+O7," (@
/*Created on 2005-7-15*/ L-`V^{R]
package com.adt.service.impl; lW|=rq-|
x,mt}>
import java.util.List; nBk&+SN
C1NU6iV^z
import net.sf.hibernate.HibernateException; Xsa8YP9
'EIe5Op
import org.flyware.util.page.Page; ra'/~^9
import org.flyware.util.page.PageUtil; /HRKw
D
>ZkL`!:s
import com.adt.bo.Result; fhN\AjB6Td
import com.adt.dao.UserDAO; 60%nQhb
import com.adt.exception.ObjectNotFoundException; n8Qv8
import com.adt.service.UserManager; $3"hOEN@5`
o_Zs0/
/** vU%K%-yXG7
* @author Joa E&cC2(w
*/ #@DJf
publicclass UserManagerImpl implements UserManager { "yQBHYP
[mv? \HDa~
private UserDAO userDAO; 9
3)fC
~!Sd|e:4
/** 2*75*EQCH
* @param userDAO The userDAO to set. *>W<n1r@]
*/ 7T[$BrO\
publicvoid setUserDAO(UserDAO userDAO){ |c0^7vrC
this.userDAO = userDAO; fd *XK/h
} R-m5(
%/I:r7UR{
/* (non-Javadoc) Ee}|!n>
* @see com.adt.service.UserManager#listUser Yd4X*Ua
#3*cA!V.<
(org.flyware.util.page.Page) Ct-eD-X{
*/ \Ki3ls
public Result listUser(Page page)throws d;dT4vx$[M
S'HA]
HibernateException, ObjectNotFoundException { 4k^P1
int totalRecords = userDAO.getUserCount(); ZX&e,X~V
if(totalRecords == 0) `_cv& "K9f
throw new ObjectNotFoundException yQ/O[(
dUa>XkPa\2
("userNotExist"); /g>-s&w
page = PageUtil.createPage(page, totalRecords); >;9g`d
List users = userDAO.getUserByPage(page); q`p0ul,n
returnnew Result(page, users); 1"CWEL`i
} ?rOj?J9
`WH$rx!
} 2+y wy^
ied1+H
>g !Z|ju
b/[X8w'VP
?S&
yF
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 z&H.fs L
By6O@ .\V
询,接下来编写UserDAO的代码: .iR<5.
3. UserDAO 和 UserDAOImpl: j>8ubA
java代码: 2
)o2d^^
Ut2T:%m{
424iFc[
/*Created on 2005-7-15*/ ykbfK$jz
package com.adt.dao; T&[6
Y}BP]#1
import java.util.List; mQ1
TXM/+sd
import org.flyware.util.page.Page; H^kOwmSzh
5xr>B7MRM?
import net.sf.hibernate.HibernateException; hkl0N%[
r rfJs
/** f4pIF"U9>
* @author Joa ?J2A.x5`a
*/ \LJ!X3TZ
publicinterface UserDAO extends BaseDAO { V/xXW=
~.x #ic
publicList getUserByName(String name)throws `scW.Vem
F-ZTy"z
HibernateException; 5)Z=FUupA~
qnyacI
publicint getUserCount()throws HibernateException; 4J[zNB]
v`mB82s
publicList getUserByPage(Page page)throws Q0"?TSY
>dK0&+A
HibernateException; @$kO7k0{g
\2+ngq)
} CRCy)AS,t
07>m*1G
iC
hIW/H
wg[
+NWJ
0#Gm# =F
java代码: "gNi}dB<]
1d+Kn Jy
O9N!SQs80
/*Created on 2005-7-15*/ @BLB.=
package com.adt.dao.impl; g~-IT&O
>k\p%{P
import java.util.List; ;B
|
X,+a 6F
import org.flyware.util.page.Page; qQ]fM$!
~m<K5K6 V
import net.sf.hibernate.HibernateException; (t3gNin
import net.sf.hibernate.Query; DXD+,y\=
>A@yF?
import com.adt.dao.UserDAO; 8Ckd.HKpQ
. 0yBI=QI
/** dpE^BW v3
* @author Joa h{"SV*Xpk/
*/ 82 |^o
public class UserDAOImpl extends BaseDAOHibernateImpl "Ia.$,k9
R%r25_8
implements UserDAO { Q*Jb0f
q'7.lrKwa>
/* (non-Javadoc) fcp_<2KH
* @see com.adt.dao.UserDAO#getUserByName .n_Z0&i/w
.s"Og;g
(java.lang.String) v$@1q9 5J
*/ Cm8h
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publicList getUserByName(String name)throws LsI@_,XW<
+ R6X
HibernateException { CB9:53zK9
String querySentence = "FROM user in class =#4>c8MM
%x,HQNRDU
com.adt.po.User WHERE user.name=:name"; g:~q&b[q6
Query query = getSession().createQuery H/`@6, j
13 L&f\b
(querySentence); ye(av&Hn
query.setParameter("name", name); z2Wblh"_
return query.list(); \kV|S=~@
} #l+Rs3T:
z7BFkZ6+
/* (non-Javadoc) C8v
* @see com.adt.dao.UserDAO#getUserCount() zQO 1%g
*/ bZUw^{~)D
publicint getUserCount()throws HibernateException { OR+_s @Yg
int count = 0; S=kO9"RB]
String querySentence = "SELECT count(*) FROM dm"x?[2:
f
uU"
user in class com.adt.po.User"; r2tE!gMC
Query query = getSession().createQuery j0oto6z~b
Qt\:A!'jw
(querySentence); 9a@S^B>
count = ((Integer)query.iterate().next P//nYPyzg
\2~\c#-k
()).intValue(); (bsywM
return count; yz,_\{}
} '`gnJX
JO
S['%>
/* (non-Javadoc) ]qZj@0#7n
* @see com.adt.dao.UserDAO#getUserByPage W,,3@:
m4uh<;C~
(org.flyware.util.page.Page) dm_Pz\*
*/ qp*~|
publicList getUserByPage(Page page)throws ,hJx3g5#n
BE&8E\w
HibernateException { *1-0s*T
String querySentence = "FROM user in class HD{u#~8{
dg*xo9Xi`
com.adt.po.User"; EJz!#f~
Query query = getSession().createQuery .
WJ
Q~Nq5[
(querySentence); R$IsP,Uw
query.setFirstResult(page.getBeginIndex()) e\aW~zs 2
.setMaxResults(page.getEveryPage()); ;B2kot7
return query.list(); rFt+Y})
} ro?.w
S{F\_'%
} [V8^}s}tF
FeZW S>N
)#4(4
@R h
v5 p`=Z@%
N0$
uB"
至此,一个完整的分页程序完成。前台的只需要调用 z*b|N45O
wZCboQ,
userManager.listUser(page)即可得到一个Page对象和结果集对象 Fsq)co
9X1vL
的综合体,而传入的参数page对象则可以由前台传入,如果用 c*axw%Us
I)jAdd
webwork,甚至可以直接在配置文件中指定。 8?'=Aeo
;){ZM,Ox
下面给出一个webwork调用示例: >(YH@Z&;
java代码: 0S+$l
}9B},
l| \ -d
/*Created on 2005-6-17*/ ettBque
package com.adt.action.user; zA|lbJz=GY
=d~pr:.F
import java.util.List; ub1~+T'O
MUtM^uY
import org.apache.commons.logging.Log; 45Zh8 k
import org.apache.commons.logging.LogFactory; o&k,aCQC
import org.flyware.util.page.Page; *yZta:(w-W
>}0H5Q8@
import com.adt.bo.Result; MVQ6I/EA4
import com.adt.service.UserService; =D?HL?
import com.opensymphony.xwork.Action; qKeR}&b
D>U(&n
/** DuAix)#FN9
* @author Joa pnuwjU-
*/ d'Dd66
publicclass ListUser implementsAction{ ,G?Kb#
P A*U\
privatestaticfinal Log logger = LogFactory.getLog Q>\DM'{:4
,0nrSJED
(ListUser.class); d7&d
FvG
Ps0<CUyI
private UserService userService; eLHhfu;k
M
$EHx[*5
private Page page; HpeU'0u0VK
E)p[^1WC
privateList users; ^xgPL'
it>l?h7 I
/*
H8@z/
* (non-Javadoc) *U\`HUW
* 7FaF]G
* @see com.opensymphony.xwork.Action#execute() r>KmrU4Q
*/ C!v%6[
publicString execute()throwsException{ BGH'&t_5
Result result = userService.listUser(page); KG(l=? N
page = result.getPage(); 2}.~
6EU/
users = result.getContent(); U? U3?Y-k`
return SUCCESS; X
g7xy>{]
} %bdBg
OYa9f[ $
/** g38MF
* @return Returns the page. K-c>J
uv&,
*/ Y)GU{
public Page getPage(){ a7b1c!
return page; eAQ-r\h'2
} 3F6A.Ny
0x&L'&SpN
/** YoQQ ,
* @return Returns the users. %l%2 hvGZ
*/ Crla~h?=
publicList getUsers(){ d,'gh4C
return users; ]_L;AD
} +n
&8" )
yS?5&oMl
/** 9RK.+2
* @param page _3g!_
* The page to set. $RC)e7
*/ GbkDs-
publicvoid setPage(Page page){ Lo)T
this.page = page; Z;dR:|%)
} d7Cs a
c
c[vFh0s"m
/** ?l|&JgJ$
* @param users v(uNqX.BC
* The users to set. @y
eAM7
*/ !,J]5$M
publicvoid setUsers(List users){ 9m"EY@-
this.users = users; ! bwy/A
} Cf
v1nUW
:[C|3KKe"
/** s,|v,,<+
* @param userService W_
;b e
* The userService to set. 9D?JzTsyg
*/ ?;_Mx al'
publicvoid setUserService(UserService userService){ +QSH*(,
this.userService = userService; G 40
} l['ER$(7
} r"VNq&v]9
gla'urb[i|
iDsY5l
pG v*{.
|$GPJaNqa
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Hr}\-$
GJF
,w{J
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 Pvm pWa
dD
6jMl
么只需要: aOUTKyR ~
java代码: *iSE)[W
$>wN:uN(
.F\[AD 5
<?xml version="1.0"?> Iq{/-,v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Nk$|nn9#'
$9G".T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- aCfWbJ@qiG
L5wFbc"u
1.0.dtd"> Pn?gB}l
{3Dm/u%=9|
<xwork> +.u
HY`A
ki?V
eFp
<package name="user" extends="webwork- _Q b].~
lI9|"^n7F
interceptors"> vcP_gJz
7VLn$q]:
<!-- The default interceptor stack name +Q :)zE
+\.0Pr
--> '^'PdB
<default-interceptor-ref ?uF3Q)rCk
R@IwmJxX
name="myDefaultWebStack"/> Iqj?wI1)
@k-GyV-v
<action name="listUser" #1'p?%K.
E7<l^/<2S+
class="com.adt.action.user.ListUser"> Ud#xgs'
<param LO%OH
u}]
_akpW
name="page.everyPage">10</param> m9ky?A,
<result PoRP]Q*n
4`?WdCW8
name="success">/user/user_list.jsp</result> @~i :8
</action> +a+DiD>./
v#5hK<9
</package> 8'Q&FW3"
ji5Nq+S2
</xwork> $A98h-*x
k+eeVy
]-OF3+l4
zpcO7AY~
@|d`n\%x
IL%P\Zs
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 l%
{<+N
d @b ]/
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 e,*@+E\4
aL8Z|*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K[q-[q#yc
PD^Cj?wm
ztC,[
tSTl#xy
8`|Z9umW*
我写的一个用于分页的类,用了泛型了,hoho /!hxW}>^
gjB(Pwx
java代码: f!B\X*|
[QwqP=-6
V$ "]f6
package com.intokr.util; AaM~B`B
1f$1~5Z
import java.util.List; X9YbTN
;jmT5XzL
/** #*"I?B/fd8
* 用于分页的类<br> .ITTY QHv)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> f Qf5%
* 3AcDW6x|
* @version 0.01 EB
p(^rj
* @author cheng j__l'?s
*/ lQVK~8t3
public class Paginator<E> { 75c\.=G9q<
privateint count = 0; // 总记录数 TTSq }sb}
privateint p = 1; // 页编号 Ge*N%=MX8
privateint num = 20; // 每页的记录数 4B-+DH>{6
privateList<E> results = null; // 结果 y# IUDnRJ
CmtDfE
/** [tJp^?6*
* 结果总数 6^z):d#u
*/ !*,m=*[3
publicint getCount(){ N1dM,H
return count; E$4Ik.k
} T?{F7
i >BQRbU
publicvoid setCount(int count){ p'=XW#2 >
this.count = count; R1Q~UX]d=
} or[! C%
2'}/aL|G
/** w2V:g$~,
* 本结果所在的页码,从1开始 z[]8"C=
* 3o_@3-Y%
* @return Returns the pageNo. [h0)V(1KR
*/ Shu=oweJ
publicint getP(){ bG]?AiWr
return p; 3Io7!:+
} =qww|B92
9y;zk$O8
/** jjg[v""3|
* if(p<=0) p=1 r@G34QC+
* 4z^VwKH\ j
* @param p &C6*"JZ4
*/ S|_"~Nd=
publicvoid setP(int p){ c,5yH
if(p <= 0) -D
wO*f
p = 1; Ots] y
this.p = p; S\6.vw!'
} 8q|T`ac+N
)fbYP@9>a
/** ?b?YiK&yz
* 每页记录数量 |N5|B Q(y$
*/ g` 41d
publicint getNum(){ %WFZ&>en&
return num; YDGW]T]i ?
} I=7 YAm[W
35~1$uRA
/** 28lor&Cc
* if(num<1) num=1 #!w7E,UBi
*/ v3r<kNW_
publicvoid setNum(int num){ IGI$,C
if(num < 1) :\|<7n
num = 1; DxG8`}+
this.num = num; :a)` iJnb
} sE\Cv2Gx
Tuy5h5
/** t0)XdIl8
* 获得总页数 6FEIQ#`{
*/ xDn#=%~+x
publicint getPageNum(){ uiaZ@
return(count - 1) / num + 1; P:m6:F@hO
} N[sJ5oF
dU|&- .rG
/** #9q
]jjH E
* 获得本页的开始编号,为 (p-1)*num+1 ] U.*KkQ
*/ 1m<8M[6u
publicint getStart(){ JQA]O/|N
return(p - 1) * num + 1; 2h`Tn{&1/
} --F6n/>
{A{sRT=%
/** N"zm
* @return Returns the results. \mNN ) K@
*/ _k Utj(re
publicList<E> getResults(){ t:tIzFNv
return results; \T^ptj(0
} Z<[:v2
f
SMy?8
public void setResults(List<E> results){ T!t9`I0Zz
this.results = results; dEPLkv
} x+W,P
&LHS<Nv^:
public String toString(){ ulNMqz\.
StringBuilder buff = new StringBuilder J,t`ilT
Lwkl*
(); ^NFL3v8
buff.append("{"); {,e-;2q
buff.append("count:").append(count); J{PNB{v
buff.append(",p:").append(p); G@o\D-$
buff.append(",nump:").append(num); $)VnHr `hy
buff.append(",results:").append uS5ADh
WL}XD
Kx
(results); B<&g
buff.append("}"); `5 MK(K
:
return buff.toString(); 6sNw#pqh
} Z8\/Fb
qR9!DQc'
} h|OWtf4
0G(|`xG1q
{EyWSf"