Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 @k)[p+)E
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 _
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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 gjn1ha"h%.
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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 GrI<w.9X
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分页支持类: {!^0j{T
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java代码: dP=,<H#]m
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package com.javaeye.common.util; vrIWw?/z?
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import java.util.List; | z?c>.
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publicclass PaginationSupport { a(lmm@;V<
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publicfinalstaticint PAGESIZE = 30; 8=OpX,t(
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privateint pageSize = PAGESIZE; +h8`8k'}-2
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privateList items; ]Rj?OSok
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privateint totalCount; h}Lrp r2r
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privateint[] indexes = newint[0]; 395`Wkv
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privateint startIndex = 0; y7x*:xR[
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public PaginationSupport(List items, int fWyXy%Qq
h)Ol1[y`
totalCount){ zBc |gx
setPageSize(PAGESIZE); !o\e/HGc!
setTotalCount(totalCount); !,R=6b$E5
setItems(items); RLfB]\w
setStartIndex(0); >fzFNcO*
} MqRJ:x
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public PaginationSupport(List items, int v^B2etiX_
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totalCount, int startIndex){ CW
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setPageSize(PAGESIZE); F<DXPToX%
setTotalCount(totalCount); O]KQ]zN
setItems(items); EAlLxXDDh
setStartIndex(startIndex); XrI$@e*
} ~~q>]4>
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public PaginationSupport(List items, int s7,D}Zz
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totalCount, int pageSize, int startIndex){ rTqGtmulG
setPageSize(pageSize); z
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setTotalCount(totalCount); U:bnX51D4
setItems(items); )FN$Jlo
setStartIndex(startIndex); E6zPN?\ <
} F>eo.|'
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publicList getItems(){ !C ZFbz~:
return items; }=|plz}
} Ey%KbvNv
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publicvoid setItems(List items){ Re*_Dt=r
this.items = items; u:H:N]
} e xkPu-[W
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publicint getPageSize(){ 6FY.kN\
return pageSize; lIPz"
} EI496bsRHm
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publicvoid setPageSize(int pageSize){ ;,s9jw
this.pageSize = pageSize; hii#kB2
} C7K]c4T
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publicint getTotalCount(){ ,c&gw tdl
return totalCount; ^I)+u>fJ
} ij1YV2v
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publicvoid setTotalCount(int totalCount){ 28vQ
if(totalCount > 0){ k U0.:Gcc
this.totalCount = totalCount; 45&Rl,2
int count = totalCount / {C0Y8:"`
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pageSize; d.HcO^
if(totalCount % pageSize > 0) ';v1AX}5q
count++; }}Z2@}
indexes = newint[count]; 6";
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for(int i = 0; i < count; i++){ mF4y0r0
indexes = pageSize * .A0fI";Q
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i; ;]@Pm<f
} #q W#>0U
}else{ hVAatn[
this.totalCount = 0; 0o:R:*
} "BZ@m:I6hy
} 3O;"{E=
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publicint[] getIndexes(){ X4{<{D`0t8
return indexes; S&QXf<v
} BWNI|pq)v
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publicvoid setIndexes(int[] indexes){ JKy~'>Q
this.indexes = indexes; pw`'q(ad
} 2[qoqd(
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publicint getStartIndex(){ E^$8nqCL:
return startIndex; =-,'LOE
} =T\=,B
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publicvoid setStartIndex(int startIndex){ (][-()YV
if(totalCount <= 0) x=+>J$~Pb
this.startIndex = 0; xP/q[7>#Q
elseif(startIndex >= totalCount) g@T}h[
this.startIndex = indexes #2Iag'4T
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[indexes.length - 1]; K$w;|UJc
elseif(startIndex < 0) `5!AHQ/
this.startIndex = 0; fI1
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else{ H8g%h}6h
this.startIndex = indexes 6P:fM Y
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[startIndex / pageSize]; t=9f:,I$
} jsx&h
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} crN*eFeW
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publicint getNextIndex(){ K?r
int nextIndex = getStartIndex() + k/sfak{Q
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pageSize; +k~0&lZi
if(nextIndex >= totalCount) %M))Ak4~a
return getStartIndex(); (w:,iw#
else P$Oj3HD LM
return nextIndex; iQS,@6
} oOC&w0
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publicint getPreviousIndex(){ lfre-pS+
int previousIndex = getStartIndex() - p|8ZHR+
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pageSize; \KzJNCOT
if(previousIndex < 0) +I3O/=)
return0; maN2(1hz
else szb@2fK
return previousIndex; U| VL+9#hd
} JgA{1@h
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} +cSc0:
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抽象业务类 iy_Y!wZ{
java代码: Pq8oK'z-
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/** N-_APWA
* Created on 2005-7-12 K&Bbjb_|
*/ Em^~OM3U$q
package com.javaeye.common.business; M=lU`Sm
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import java.io.Serializable; C=]<R<Xy
import java.util.List; MkL2I+*
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import org.hibernate.Criteria; 0y+^{@lU
import org.hibernate.HibernateException; G"OP`OMDc
import org.hibernate.Session; b9m`y*My
import org.hibernate.criterion.DetachedCriteria; GqR|hg
import org.hibernate.criterion.Projections; sZT~5c8
import ^D6TeH
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org.springframework.orm.hibernate3.HibernateCallback; elQjPvb
import C\~}ySQc.e
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org.springframework.orm.hibernate3.support.HibernateDaoS `lWGwFg g(
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upport; 8V 4e\q
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import com.javaeye.common.util.PaginationSupport; Y0T :%
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public abstract class AbstractManager extends AU}kIm_+
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HibernateDaoSupport { IGQBTdPUa
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privateboolean cacheQueries = false; Q?1J<(oq9
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privateString queryCacheRegion; 4=/jh:h
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publicvoid setCacheQueries(boolean 1n +Uv*
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cacheQueries){ A|S)cr8z
this.cacheQueries = cacheQueries; 6p*X8j3pW
} rDhQ3iCqo
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publicvoid setQueryCacheRegion(String Qn.dL@W
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queryCacheRegion){ 0NGth(2
this.queryCacheRegion = z k/`Uz
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queryCacheRegion; W"\}##
} 6j XDLI
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publicvoid save(finalObject entity){ =eUKpYI
getHibernateTemplate().save(entity); 5X=1a*2']
} Zk((VZ(y
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publicvoid persist(finalObject entity){ gBv!E9~l
getHibernateTemplate().save(entity); [,,@>nyD
} $"W[e"Q
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publicvoid update(finalObject entity){ nPdkvs
getHibernateTemplate().update(entity); zGR,}v%%
} -dA9x~o
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publicvoid delete(finalObject entity){ $cHU,
getHibernateTemplate().delete(entity); kY\faWuR
} Nh }-6|M
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publicObject load(finalClass entity, g:ky;-G8b
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finalSerializable id){ $<nRW*d
return getHibernateTemplate().load %W\NYSm
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(entity, id); L%/>Le}VX
} W+1nf:AI.
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publicObject get(finalClass entity, l`zhKj
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finalSerializable id){ <<u]WsW{C
return getHibernateTemplate().get (m:Q'4Ep
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(entity, id); \tYImh
} jq% <Z,rh
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publicList findAll(finalClass entity){ ]jxyaE&%4
return getHibernateTemplate().find("from jH9PD8D\
@I?,!3`jS
" + entity.getName()); '1LN)Yw
}
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publicList findByNamedQuery(finalString xOKJOl
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namedQuery){ @2h hB W
return getHibernateTemplate >IrQhSF
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().findByNamedQuery(namedQuery); eLPtdP5k
} IC'+{3.m8
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publicList findByNamedQuery(finalString query, S/) ),~`4
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finalObject parameter){ <Hr<QiAK
return getHibernateTemplate #1E4
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().findByNamedQuery(query, parameter); H!]&"V77
} -%MXt
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publicList findByNamedQuery(finalString query, /B?wn=][
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finalObject[] parameters){ 01-rBto$
return getHibernateTemplate h<3b+*wYJC
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().findByNamedQuery(query, parameters); #;a+)~3*O
} #Mn?Nn
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publicList find(finalString query){ onSt%5{P%X
return getHibernateTemplate().find ?wG
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(query); z3i`O
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} Yv]vl6<
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publicList find(finalString query, finalObject BedL `[,
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parameter){ XLpn3sX$
return getHibernateTemplate().find L;")C,CwQ
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(query, parameter); GBb8}lx
} *
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public PaginationSupport findPageByCriteria eR5q3E/;G
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(final DetachedCriteria detachedCriteria){ HN NeH;L
return findPageByCriteria 5A`>3w{3n
k8}fKVU;
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ASoBa&vX
} p1niS:}j
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public PaginationSupport findPageByCriteria ZrEou}z(*
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(final DetachedCriteria detachedCriteria, finalint 18%$Z$K,
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startIndex){ 8Gy]nD
return findPageByCriteria 2EpQ(G
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(detachedCriteria, PaginationSupport.PAGESIZE, i=n;rT
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startIndex); L@[}sMdq(
} V)~b+D
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public PaginationSupport findPageByCriteria !%t@wQ]\hG
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(final DetachedCriteria detachedCriteria, finalint nw/g[/<;
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pageSize, K\Q4u4DjbJ
finalint startIndex){ %1k"K~eu
return(PaginationSupport) |;a$
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getHibernateTemplate().execute(new HibernateCallback(){ n-M6~
publicObject doInHibernate >qy62:co
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(Session session)throws HibernateException { 3n7>qZ.d
Criteria criteria = 0AWxU?$A4
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detachedCriteria.getExecutableCriteria(session); U`~L}w"
int totalCount = Pl'lmUR
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((Integer) criteria.setProjection(Projections.rowCount J#wf`VR%
bz nMD
()).uniqueResult()).intValue(); 9s5s;ntz"
criteria.setProjection nnRb
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(null); [AFR \{
List items = Xmmj.ZUr
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criteria.setFirstResult(startIndex).setMaxResults ]lGkZyUhI
zwQ#Yvd
(pageSize).list(); U+B{\38
PaginationSupport ps = X=?9-z]
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new PaginationSupport(items, totalCount, pageSize, m=h/A xW
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startIndex); jt6_1^
return ps; 1
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} ?Mo)&,__
}, true); = =pQ
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} )g8Kicox5
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public List findAllByCriteria(final Q$p3cepsK
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DetachedCriteria detachedCriteria){ )Dhx6xM[a
return(List) getHibernateTemplate ~FAk4z=Ed
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().execute(new HibernateCallback(){ NoF|j57?u'
publicObject doInHibernate B)DuikV.D
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(Session session)throws HibernateException { X^&--@l}T!
Criteria criteria = R>Ox(MG
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detachedCriteria.getExecutableCriteria(session); [C-FJ>=S
return criteria.list(); GK6~~ga=
} @||nd,i`n~
}, true); &QQ6F>'T
} %b_0l<+
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public int getCountByCriteria(final w
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DetachedCriteria detachedCriteria){ { **W7\h
Integer count = (Integer) 8.wtv5eZ
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getHibernateTemplate().execute(new HibernateCallback(){ j)ln"u0R^B
publicObject doInHibernate "tJ[M
t}}Ti$$>
(Session session)throws HibernateException { \O~/^ Y3U!
Criteria criteria = #d<"Ub
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detachedCriteria.getExecutableCriteria(session); <ir]bQT
return Xep2)3k>
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criteria.setProjection(Projections.rowCount ^"iL|3d
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()).uniqueResult(); hDg"?{
} `DGI|3
}, true); 7N OF^/nU
return count.intValue(); /i_FA]Go
} qM3NQ8Rm
} b$
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用户在web层构造查询条件detachedCriteria,和可选的 x<w-j[{k_K
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7z\#"~(.
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PaginationSupport的实例ps。 yZoJD{'?Sw
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ps.getItems()得到已分页好的结果集 3,hu3"@k
ps.getIndexes()得到分页索引的数组 ]M "U 'Z
ps.getTotalCount()得到总结果数 ^HuB40
ps.getStartIndex()当前分页索引 4kV$JV.l
ps.getNextIndex()下一页索引 ;ioF'ov
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5K&A2zC|
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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 bQN3\mvY
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一下代码重构了。 I+3=|Vef
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我把原本我的做法也提供出来供大家讨论吧: Bz%wV-
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首先,为了实现分页查询,我封装了一个Page类: $Dv5TUKw
java代码: 9`H4"H>yG
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#
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/*Created on 2005-4-14*/ f\RTO63|O
package org.flyware.util.page; _T805<aUW\
%'X7T^uE
/** k7sD"xR3
* @author Joa -i91nMi]
* #Lk~{
*/ x.Ny@l%]
publicclass Page { 8NNs_~+x}
;V f{3
/** imply if the page has previous page */ 5vS[{;<&
privateboolean hasPrePage; -V"W
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/** imply if the page has next page */ !N][W#:
privateboolean hasNextPage; 3-Xd9ou
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/** the number of every page */ nLANWQk9
privateint everyPage; w|0:0Rc~u
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/** the total page number */ !`W0;0'Zg
privateint totalPage; c|k(_#\B
DV>;sCMJ %
/** the number of current page */ LU@1Gol
privateint currentPage; f+)LVT8p
nq+6ipx
/** the begin index of the records by the current =E(ed,gH8
oS Ybx:2wo
query */ JIYzk]Tj
privateint beginIndex; 68<W6z
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/** The default constructor */ tef>Py
public Page(){ D=.Ob<m`Z
kf |J
} i]@k'2N
%z.d;[Hs
/** construct the page by everyPage DqmKDU
* @param everyPage /+ais3
* */ JFNjc:4{0
public Page(int everyPage){ !HhF*Rlr
this.everyPage = everyPage; s%~Nx3,
} 0~[M[T\
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/** The whole constructor */ Be^"sC
public Page(boolean hasPrePage, boolean hasNextPage, B*tQ0`
{F\P3-ub
tehWGqx)
int everyPage, int totalPage, XW^Pz(
int currentPage, int beginIndex){ d6??OO=~>M
this.hasPrePage = hasPrePage; A9J{>f
this.hasNextPage = hasNextPage; F,K))325
this.everyPage = everyPage; q['3M<q
this.totalPage = totalPage; }5$le]
this.currentPage = currentPage; Yn?Xo_Y
this.beginIndex = beginIndex; nYvkeT
} Lm1JiPs d
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/** ,[dvs&-*
* @return [a~@6*=
* Returns the beginIndex. 3Q7PY46
*/ 7Xh @%[
publicint getBeginIndex(){ )"2eN3H/
return beginIndex; ,4-],~T
} x'6i9]+r
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/** DFRgn
* @param beginIndex id`RscV]
* The beginIndex to set. >f1fvv6
*/ `JGW8 _
publicvoid setBeginIndex(int beginIndex){ +Ll29Buyi
this.beginIndex = beginIndex; "Wb KhE
} 'L{pS-+6
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/** wM-H5\9n
* @return ?zVE7;r4U
* Returns the currentPage. D)S_ p&
*/ ;/IXw>O(/
publicint getCurrentPage(){ _t4(H))]vG
return currentPage; 55Mtjqfp
} o>&pj
z fy(j
/** 9d=\BBNZ
* @param currentPage E4.A$/s8[
* The currentPage to set. mGmZ}H'{
*/ "W9z>ezp
publicvoid setCurrentPage(int currentPage){ ^![7X'!;pt
this.currentPage = currentPage; ~~t>;
} J?4dafkw
CalWJ
/** 28-z
* @return I,]q;lEMt
* Returns the everyPage. :RBeq,QaO
*/ >Af0S;S
publicint getEveryPage(){ OKu~Nb*
return everyPage; Z\n^m^Z
=
} ^i3!1cS
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/** d+0= a]
* @param everyPage W58%Zz4a
* The everyPage to set. A
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*/ 0|=y#`;,Z
publicvoid setEveryPage(int everyPage){ +-5YmN'
this.everyPage = everyPage; I@#IXH?6
} ,WW=,P
Z,~@_;F
/** M@*Y&(~
* @return z|(<Co8#.
* Returns the hasNextPage. :vaVghN\
*/ Wu8zK=Ve(
publicboolean getHasNextPage(){ fZnq5rTk"
return hasNextPage; Bcb
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} qamq9F$V
M}=>~TA@
/** !g#y$
* @param hasNextPage KhL%ov
* The hasNextPage to set. }"kF<gG1
*/ D& &71X '
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; qHd7C3
} |S:erYE,G
@,W5K$Ka=
/** p&HO~J<w
* @return EV|W:;Sg
* Returns the hasPrePage. _[wG-W/9R
*/ hVd_1|/X
publicboolean getHasPrePage(){ 8;f5;7Mn
return hasPrePage; l%2 gM7WMY
} n5tsaU;
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/** lB#7j
* @param hasPrePage 5as5{"l
* The hasPrePage to set. 'cc{sjG
*/ Np$ue
}yr
publicvoid setHasPrePage(boolean hasPrePage){ l2Rnyb<;;
this.hasPrePage = hasPrePage; it-2]Nw
} E!L_"GW
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/** T~g`;Q%i
* @return Returns the totalPage. -"#jRP]#
* _U^G*EqL*
*/ vCOtED*<
publicint getTotalPage(){ 2gEF$?+q?
return totalPage; K&T.~2'>
} ,,ML^ey
_C|j"f/}
/** KYz@H#M
* @param totalPage \,lIPA/L
* The totalPage to set. ;(K"w*
*/ ,<s:*
k
publicvoid setTotalPage(int totalPage){ aH_FBY
this.totalPage = totalPage; k_gl$`A
} 79h'sp6;
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} ph%t
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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 by,3A
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个PageUtil,负责对Page对象进行构造: M(^ e)7a1
java代码: \#F>R,
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/*Created on 2005-4-14*/ Tiimb[|
package org.flyware.util.page; #GUD^#Jh
##Qy6Dc
import org.apache.commons.logging.Log; 4Bt)t#0
import org.apache.commons.logging.LogFactory; T!^v^m@>y
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/** 6X!jNh$oF
* @author Joa 2|NQ5OA0
* 6(ER$
*/ !lM.1gTTC
publicclass PageUtil { [Ov/&jD"
aO
bp"
privatestaticfinal Log logger = LogFactory.getLog g*w}m>O
:dxKcg7
(PageUtil.class); 8;,|z%rS"
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/** 1Cw$^jd
* Use the origin page to create a new page q &S@\b
* @param page O.-A)S@
* @param totalRecords kX)*:~*
* @return 0+.<BOcW5
*/ Xc~BHEp
publicstatic Page createPage(Page page, int }
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XG
totalRecords){ iI &z5Q2
return createPage(page.getEveryPage(), XdnpL$0
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page.getCurrentPage(), totalRecords); Zt9ld=T
} 8m[o*E.4F
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/** HJd{j,M
* the basic page utils not including exception ?>gr9w\
S9'Xsh
handler ;3%Y@FS@
* @param everyPage 6:Y2z!MLO
* @param currentPage D'^UZZlI^I
* @param totalRecords #Kx @:I
* @return page Tz0XBH_
*/ su\`E&0V+
publicstatic Page createPage(int everyPage, int (.5Ft^3W
<vb7X
currentPage, int totalRecords){ uWP0(6 %
everyPage = getEveryPage(everyPage); *Y!RU{w+Z
currentPage = getCurrentPage(currentPage); b~<:k\EE
int beginIndex = getBeginIndex(everyPage, f>&*%[fw
*<}R=X.
currentPage); 46B'Ec
int totalPage = getTotalPage(everyPage, Q:'r
p
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totalRecords); 8I<j"6`+Q
boolean hasNextPage = hasNextPage(currentPage, A.RG8"
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totalPage); $FZcvo3@*S
boolean hasPrePage = hasPrePage(currentPage); Tl+PRR6D*
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returnnew Page(hasPrePage, hasNextPage, Fzn!
everyPage, totalPage, 0<^Qj.(9
currentPage, q%,y66pFr
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beginIndex); APCE}%1U
} 4ti,R'
U r8JG&,
privatestaticint getEveryPage(int everyPage){ k?1e+ \
return everyPage == 0 ? 10 : everyPage; ]u:Ij|.'y0
} kxmsrQ>av
tJGK9!MH{(
privatestaticint getCurrentPage(int currentPage){ {s6hi#R>
return currentPage == 0 ? 1 : currentPage; h${=gSJc
} _SH~.Mt_!
7h>,
privatestaticint getBeginIndex(int everyPage, int Zlygx
R 0G!5>1i
currentPage){ qc a=a}
return(currentPage - 1) * everyPage; Pu 'NSNT
} K@{R?j/+
xqauSW
privatestaticint getTotalPage(int everyPage, int (UTA3Db
$bN_0s0:'
totalRecords){ Xo6zeLHO
int totalPage = 0; -U\s.FI.AR
$+,kibk*R
if(totalRecords % everyPage == 0) R3.8Dr0f
totalPage = totalRecords / everyPage; 42:,*4t(
else RVF<l?EI4R
totalPage = totalRecords / everyPage + 1 ; 6_:KFqc W
w{4#Q[
return totalPage; iRM ?_|
} &vfeBth
?=HoU3
privatestaticboolean hasPrePage(int currentPage){ J0o,ZH9
return currentPage == 1 ? false : true; <~u-zaN<W
} Or55_E
E5a7p.
privatestaticboolean hasNextPage(int currentPage, L[U?{
AtqsrYj
int totalPage){ :4LWm<P
return currentPage == totalPage || totalPage == nj-LG!"a
J<&?Hb*|
0 ? false : true; tJm1Q#||
} ):n'B` f}z
Dv4 H^
-a'D~EGB^
} Lzx/9PPYn
.\3gb6S}
~K
('t9|
t Q.%f:|
HHOqJb{8S
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 AXv-%k};
}}oIZP\qM
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 "
BU4\QF-
*@WBaN+
做法如下: =<AG}by![
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 j!@,r^(
x Vw1
的信息,和一个结果集List: ]@CXUa,>a
java代码: |;"(C# B
?uW}
XAi
Cn_r?1{W
/*Created on 2005-6-13*/ M}
+s_h9
package com.adt.bo; k4` %.;
i1 GQ=@
import java.util.List; we
kb&?
Fz| r[
import org.flyware.util.page.Page; 6p.y/LMO
5fLp?`T
/** y!|4]/G]?t
* @author Joa +=*ND<$n/E
*/ //bQD>NBO
publicclass Result { Fw^^sB
b27t-p8
private Page page; Rhw+~gd*F
74hRG~
private List content; 'CRjd~L
[]?*}o5&>T
/** /74)c~.W
* The default constructor Gsz$H_
*/ ]}.|b6\
public Result(){ ^Of\l:q*
super(); g``S SU
} FMitIM*]
.Vs|&c2im
/** 7324#Hw S
* The constructor using fields 5JG`FRW!
* om6`>I*
* @param page Vygh|UEo
* @param content Gc;-zq
*/ /sqfw,h@
public Result(Page page, List content){ j|b$b,rF\
this.page = page; \)2'+R
this.content = content; Z}3;Ych
} wp@6RJ
kc2
8Q2
/** jV<5GWq
* @return Returns the content. +^.xLTX`$
*/ Wxi;Tq9C@_
publicList getContent(){ Q v},X~^R
return content; Ij9=J1c4
} v7D0E[)~
VS65SxHA
/** BU|m{YZ$
* @return Returns the page. /)4Q%Zp
*/ ciW;sK8
public Page getPage(){ d-gcXaA-8
return page; SUL\|z`5
} oq(W|
nd5.Py$
/** 2\F'So
* @param content sBNqg~HwB?
* The content to set. AR
g]GV/L
*/ |Vp
?
public void setContent(List content){ `*]r+J2
this.content = content; zY].ZS=7
} .mxc~
YDgG2hT/2
/** cu#r#0U-
* @param page 'yh)6mid
* The page to set. +u
lxCm_lV
*/ T
^/\Rr
publicvoid setPage(Page page){ "J`#
this.page = page; BiZYGq
} tw]
l
} dd4^4X`j
ho!qXS
TnuA uui*
zJOyr"B'8
j
~I_by
2. 编写业务逻辑接口,并实现它(UserManager, 4UN|`'c
M1*x47bN
UserManagerImpl) P|a|4Bb+fW
java代码: d-I=xpB
D8b9T.[(
-)DxF<8B
/*Created on 2005-7-15*/ .EjjCE/v-
package com.adt.service; DH.CAV
zXe]P(p<
import net.sf.hibernate.HibernateException; 0bu!(Tpg7
qR4-~p8
import org.flyware.util.page.Page; vI(CX]o
q%XjJ -s:
import com.adt.bo.Result; @J6V,
]@l;;Sp
/** O_*tDq,e
* @author Joa _?XR;2]
*/ s|R`$+'{
publicinterface UserManager { `*B6T7p1
^Jc|d,u;s
public Result listUser(Page page)throws OSwum!hzN
M0]J`fL@
HibernateException; XFi9qL^
2l~qzT-
} pQ8f$I#v
=
jTC+0u
.la_u8A]
"rpP
3RI%OCGF
java代码: 1WI^RlWd(
3X9
G(1_P1
/*Created on 2005-7-15*/ `b_n\pf]
package com.adt.service.impl; R-Y 7I
V7k!;0u
v
import java.util.List; HUel
Q@Cy\l
import net.sf.hibernate.HibernateException; !z5Ozm+}
-R`nitf
import org.flyware.util.page.Page; Y{8}z
ZD
import org.flyware.util.page.PageUtil; $$'[%
c7R6.T
import com.adt.bo.Result; mzf^`/NO
import com.adt.dao.UserDAO; c >xHaA:V
import com.adt.exception.ObjectNotFoundException; %~N| RSec
import com.adt.service.UserManager; ^KQZ;[B
C0&ZQvvy1:
/** X$_z"t
* @author Joa E.CG
*/ (,RL\1zJ
publicclass UserManagerImpl implements UserManager { {G=|fgz
"[CR5q9Pr
private UserDAO userDAO; Ubh)}G,Mg
pc;`Fz/`7
/** q oz[x
* @param userDAO The userDAO to set. 2hb>6Z;r]K
*/ 5$*=;ls>J
publicvoid setUserDAO(UserDAO userDAO){ 2UTmQOm
this.userDAO = userDAO; 2rM/kF >g
} *tl; 0<n
N\fj[?f[
/* (non-Javadoc) c(s: f@ 1
* @see com.adt.service.UserManager#listUser -s7a\H{~
.F0Q<s9
(org.flyware.util.page.Page) $/Llzpvny
*/ Z 3-=TN
public Result listUser(Page page)throws IJLuu@kRm,
:VX2&*
HibernateException, ObjectNotFoundException { g!`^!Q/($
int totalRecords = userDAO.getUserCount(); Bsj^R\
if(totalRecords == 0) `F_R J.g*p
throw new ObjectNotFoundException ;/!o0:m^I
R'^J#"[
("userNotExist"); @/='BVb'T
page = PageUtil.createPage(page, totalRecords); g2YE^EKU~
List users = userDAO.getUserByPage(page); HgTBON(
returnnew Result(page, users); 9x#Tj/5%
} X: QRy9]
$ou/ Fn
} }eSrJgF4M
)c<[@::i
((6?b5[
NOl/y@#
3.h0
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q3[nS(#Z/=
|)[&V3+|
询,接下来编写UserDAO的代码: %kuUQ%W1
3. UserDAO 和 UserDAOImpl: AH^ud*3F
java代码: b .cBg.a
w3"%d~/[x
i({MID)/_
/*Created on 2005-7-15*/ \cHFV
package com.adt.dao; _TbvQY
N,&bBp
import java.util.List; Q5*"t*L!N
<,J O
import org.flyware.util.page.Page; Li\b,_C
*nwH1FjH
import net.sf.hibernate.HibernateException; 2>m"CG
SU(J
/** &H2j3De
* @author Joa jV#1d8qm
*/ 4\ny]A:~
publicinterface UserDAO extends BaseDAO { 0"iQHi
@QDpw1;V'
publicList getUserByName(String name)throws |wuN`;gc"
0,6!6>BOT
HibernateException; +[pJr-k
Vr #o]v
publicint getUserCount()throws HibernateException; ix 5\Y
DO~~
publicList getUserByPage(Page page)throws ucUuhS5
(mx}6A
HibernateException; T;3B_lu]
vyT-!mC
} y4Nam87;/?
^j<2s"S
4r9AU mJqw
FmQiy+.|
1JZhcfG
java代码: KD'}9{F,
!iUT Re
4!Lj\.!$
/*Created on 2005-7-15*/ Qi|k,1A0
package com.adt.dao.impl; t]xR`Rr;X
5w</Ga
import java.util.List; wLo<gA6;
r`PD}6\
import org.flyware.util.page.Page; {-yw@Kq
L"(
{6H
import net.sf.hibernate.HibernateException; K^%ONultv
import net.sf.hibernate.Query; xxpzz(S ]A
:v^Od W
import com.adt.dao.UserDAO; !ZayN
c`7 dNx
/** Y7 e1%,$v
* @author Joa yRt7&,}zL
*/ Lo}zT-F
public class UserDAOImpl extends BaseDAOHibernateImpl n^/)T3mz{
D~ 7W
implements UserDAO { =an0PN
|zOwC9-6
/* (non-Javadoc) 4C9k0]k2
* @see com.adt.dao.UserDAO#getUserByName n{"a0O
MK <\:g
(java.lang.String) n"nfEA3{`
*/ \
F)}brPc
publicList getUserByName(String name)throws <6C:\{eo
Y$W)JWMY`
HibernateException { p-,Bq!aG$
String querySentence = "FROM user in class !'a
<Dw5
</_.+c [
com.adt.po.User WHERE user.name=:name"; Nu+DVIM
Query query = getSession().createQuery `{Fz
!'> ,37()
(querySentence); FPu$N d&\
query.setParameter("name", name); cpphnGj5
return query.list(); vHb^@z=
} '|G8yojz
G'{&*]Z\:
/* (non-Javadoc) $5>m\wrl
* @see com.adt.dao.UserDAO#getUserCount() Au*1-
*/ TwKi_nh2m
publicint getUserCount()throws HibernateException { %{0F.
int count = 0; *TPWLR ^
String querySentence = "SELECT count(*) FROM dEam|
hbs /S
user in class com.adt.po.User"; nY,LQ0r
Query query = getSession().createQuery \+k~p:d_8
{HjJ9ZGQ
(querySentence); `tl -] ^Y2
count = ((Integer)query.iterate().next 3=%G{L16-
So4#n7
()).intValue(); 2%)~E50U
return count; Jv!f6*&<
} o Va[
nD}<zj$D2
/* (non-Javadoc) t|*UlTLm
* @see com.adt.dao.UserDAO#getUserByPage k;r[m,$
\p!m/2
(org.flyware.util.page.Page) h;~NA}>
*/ _WI~b
publicList getUserByPage(Page page)throws :N'
M%s!qC+
HibernateException { V6'k\5| _
String querySentence = "FROM user in class {~#d_!(
&%T*sR
com.adt.po.User"; T#HF!GH]
Query query = getSession().createQuery BRv#`
V(Oi!(H;v
(querySentence); Y@+9Ukd/
query.setFirstResult(page.getBeginIndex()) #z}0]GJKj
.setMaxResults(page.getEveryPage()); U@:l~xJ
return query.list(); .ZM0cwF
} 4I2#L+W
,2P/[ :
} &uI33=
qipS`:TER
1;v wreJ
#r]GnC,
D3y4e8+Z'
至此,一个完整的分页程序完成。前台的只需要调用 "WH
&BhQYD
wkT4R\H >
userManager.listUser(page)即可得到一个Page对象和结果集对象 SRrp=>w?
^[v>B@p*{
的综合体,而传入的参数page对象则可以由前台传入,如果用 lo36b zbT
{_ZbPPh;M"
webwork,甚至可以直接在配置文件中指定。 "%{J$o
Z<6Fq*I
下面给出一个webwork调用示例: rTLo6wI
java代码: UNd+MHE74I
NW@guhK.
Rac4a@hZ
/*Created on 2005-6-17*/ EXTQ:HSES
package com.adt.action.user; ,#QLc
:TN^}RML
import java.util.List; d(j|8/tpA
rD SUhO{V
import org.apache.commons.logging.Log; \l9S5%L9
import org.apache.commons.logging.LogFactory; X| X~|&j
import org.flyware.util.page.Page; p}R3AJ
8gI~x.k`
import com.adt.bo.Result; Qg4g(0E@
import com.adt.service.UserService; V61.UEN
import com.opensymphony.xwork.Action; m;"dLUb
)nJh) {4\
/** Fl&Z}&5p
* @author Joa %O_Ed
{G4t
*/ p(]o#$ 6[
publicclass ListUser implementsAction{ h2]gA_T`
*/yR_f
privatestaticfinal Log logger = LogFactory.getLog {!rpE7P-
~g[<A?0=y
(ListUser.class); X:Z*7P/
A('_.J=
private UserService userService; Mee+bp
wth*H$iF
private Page page; >
:
;*3
b];? tP
privateList users; -YHyJs-bU
;+h-o
/* =/jCDY
* (non-Javadoc) %;{Ro)03
* Us*"g{PQ
* @see com.opensymphony.xwork.Action#execute() ($ l
t@j
*/ 4S+sz?W2j
publicString execute()throwsException{ 79JU
Result result = userService.listUser(page); K9(Su`zr
page = result.getPage(); Ei[>%Ah
users = result.getContent(); 4q7hL
return SUCCESS; HQOz
} g`BtG
;jgJI~3l
/**
3l8k O
* @return Returns the page. )Cm7v@B
*/ $yA2c^QS
public Page getPage(){ 8P#jC$<
return page; ADQ#qA,/
} :UgCP ~Y
^cy.iolt
/**
Mmu>&C\
* @return Returns the users. &CEZ+\bA
*/ 1hQeuG
publicList getUsers(){ A=5A8B1
return users; hnbF}AD
} .s)z?31
ZV;lr Vv
/** ;ESuj'*t
* @param page JWuF ?<+k
* The page to set. ~A5MzrvIO2
*/ ^l(Kj3gM
publicvoid setPage(Page page){ wwtk6;8@
this.page = page; </OZ,3J=
} E4nj*Lp~+
??!+2G#%!
/** 7Q(5Nlfcz
* @param users P;#}@ /E
* The users to set. I C6}s
*/ D/$$"AT
publicvoid setUsers(List users){
%0z&k!P
this.users = users; ~HH#aXh*
} FYe(SV(9
!\0UEC
/** QQ5G?E
* @param userService JY|f zL
* The userService to set. CqRG !J
*/ Fj`6v"h
publicvoid setUserService(UserService userService){ BihXYux*
this.userService = userService; BmRk|b
} )@
/!B`
} L;7x2&
"Yo.]PU
#N=!O/Y
Ighd,G-
="$9
<wt
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, S9$* w!W
uHv9D%R
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 [ET03 nZ
_oB!-#
么只需要: ov{
java代码: oCBZ9PGkK
o2FQ/EIE
~v2E<S3
<?xml version="1.0"?> :<
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork poqcoSL"}
l@x/{0
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 1]L 0r
W?5u O
1.0.dtd"> 7j&iHL
\;z*j|;B
<xwork> ,qS-T'[v,(
H]LH~l
<package name="user" extends="webwork- ^6*2a(S&
CH6^;.
interceptors"> Jl-Lz03YG
2L#$WuM~^
<!-- The default interceptor stack name +mReWf:o
RJ ,a}w[9
--> p#VA-RSUQ|
<default-interceptor-ref _H:mBk,,
k^
CFu
name="myDefaultWebStack"/> 0] 'Bd`e
`u%`Nj
<action name="listUser" :27GqY,3sK
os<B}D[
class="com.adt.action.user.ListUser"> }uJH!@j
<param v !~lVv&
rZ0+mS'/G
name="page.everyPage">10</param> %!5[3b'h
<result g1JBssw&m
R<}n?f\#JZ
name="success">/user/user_list.jsp</result> _5F8F4QY`
</action> /8\gT(@
A4lh`n5%
</package> uqaP\
>[]@Df,p
</xwork> H"_ZqEg
J. ;9-
o ]UG*2
#&JhA2]q
}g1V6`8&
$9pFRQC'q
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 KLpe!8tAe
%F'*0<
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。 K3QE>@']
P4xQ:$2!
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 o1x IGP<
C?v_ig
cO9aT
V)
#vvnq
N"X;aVFs_
我写的一个用于分页的类,用了泛型了,hoho 3urL*Fw,
M_-LI4>
java代码: ~)';[Ha
L*TPLS[lh
t2)S61Vr
package com.intokr.util; s68&AB
g3r4>SA
import java.util.List; DA)mkp
da c?b(
/** 9C?;'
* 用于分页的类<br> Lq#>N_72W0
* 可以用于传递查询的结果也可以用于传送查询的参数<br> =|lw~CW
* .G"UM>.}d
* @version 0.01 "I"(yiKD
* @author cheng *\9JIi 2
*/ [ugBVnma
public class Paginator<E> { Tk[`kmb
privateint count = 0; // 总记录数 ( Z-~Eh
privateint p = 1; // 页编号 "c[ D0{\{
privateint num = 20; // 每页的记录数 cVrses^yE
privateList<E> results = null; // 结果 J&%d(EJM
;t'~
/** j7&57'
* 结果总数 !!NVx\a
*/ $S~e"ca1
publicint getCount(){ yQkj4v{
return count; seT?:PCA
} B^W0Ik`m
1aC?*,e?
publicvoid setCount(int count){ J1,\Q<
this.count = count; ZJL[#}*
} [cSoo+Mlx
<"|BuK
/** %xE9vN;
* 本结果所在的页码,从1开始 &"v h=Z-
* _e/>CiN/
* @return Returns the pageNo. tx=~bm"*?
*/ <mE)&7C
publicint getP(){ G.KZZ-=_4
return p; F\1{b N|3
} 9Ra_[1
\ "193CW!
/** $7q'Be@{
* if(p<=0) p=1 S^}@X?v
* vAW+ ,Rfj
* @param p c hE~UQ
*/ b"-eQb
publicvoid setP(int p){ :'-FaGy
if(p <= 0) psb$rbu7[
p = 1; !MNo
8dC;
this.p = p; Yrb[:;Y
} /6_>d$
'2+Rb7V
/** 1n7tmRl
* 每页记录数量 *c} MI
e'&
*/ g0-hN%=6
publicint getNum(){ ;qT~81
return num; /p|]*={
} D4?qw$"
S?.2V@Ic
/** n dRy&[f7
* if(num<1) num=1 q7-Eu4w
*/ ^J0*]k%
publicvoid setNum(int num){ ^Xjh ?+WM
if(num < 1) x|/zn<\^
num = 1; ,}%+5yH
this.num = num; $0rSb0[
} B6tp,Np5,
3^kZydZCN
/** 6yZfV7I
* 获得总页数 Q8.SD p
*/ U[9`:aV;
publicint getPageNum(){ M|e
Qds
return(count - 1) / num + 1; vluA46c
} gf6<`+/
k?|l;6
/** (hTe53d<S?
* 获得本页的开始编号,为 (p-1)*num+1 @$ E&H`da
*/ aaf\% ~
publicint getStart(){ Y4,~s64e
return(p - 1) * num + 1; pv%UsbY
} mjUln8Jc
l v]TE"
/** .L'>1H]B
* @return Returns the results. `9SRiy
*/ lb3: #?
publicList<E> getResults(){ "#x<>a)O\
return results; H8j#rC#&pm
} p(/PG+
HJT}v/FZ
public void setResults(List<E> results){ - 7)%J+5
this.results = results; ?<c)r~9]
} E/@w6uIK[
HgJ:R f]
public String toString(){ 6?nAO
StringBuilder buff = new StringBuilder zSMNk AM
a[iuE`
(); VH1PC
buff.append("{"); uev$5jlX
buff.append("count:").append(count); v5U\E`)s
buff.append(",p:").append(p); &U:bRzD
buff.append(",nump:").append(num); <oG+=h
buff.append(",results:").append ehQ"<.sQ
lNuZg9h
(results); YnC7e2
buff.append("}"); `HXP*Bp#
return buff.toString(); T-x1jC!B'
} *het_;)+{
$PA=7`\MP/
} kylR)
NQzpgf|h
qUX