Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6J"(xT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !3?yG
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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 7dHIW!OA
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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 C
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分页支持类: KDBY9`08
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java代码: L W?&a3e
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package com.javaeye.common.util; 4a?r` '
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import java.util.List; RJLFj
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publicclass PaginationSupport { ^1Yo-T(R
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publicfinalstaticint PAGESIZE = 30; LC76 Qi;|k
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privateint pageSize = PAGESIZE; `T`c@A
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privateList items; 7G2vYKC'
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privateint totalCount; p8_2y~!
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privateint[] indexes = newint[0]; rCkYfTYI
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privateint startIndex = 0; &62`Wr 0C
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public PaginationSupport(List items, int Y6+k9$h
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totalCount){ kv/(rKLp*
setPageSize(PAGESIZE); sC9-+}
setTotalCount(totalCount); 9X.gg$P
setItems(items); b~F!.^7Q
setStartIndex(0); Up'."w_zE
} nwhm[AaNs
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public PaginationSupport(List items, int A
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totalCount, int startIndex){ '8L(f w{k
setPageSize(PAGESIZE); UQSX<6"
setTotalCount(totalCount); 9*f2b.Aj
setItems(items); )ynA:LXx
setStartIndex(startIndex); zz[g{[SN
} V2lp7"
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public PaginationSupport(List items, int >c&4_?d&,A
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totalCount, int pageSize, int startIndex){ MM=W9#
setPageSize(pageSize); #*[,woNk
setTotalCount(totalCount); S$Qr@5
setItems(items); 3KDu!w@
setStartIndex(startIndex); (/To?`
} @"jmI&hYn
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publicList getItems(){ S83]O!w0
return items; ;L#LDk{Za
} jq7vOr-_g
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publicvoid setItems(List items){ K]*g, s+
this.items = items; 8}ii3P y
} V]+o)A$
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publicint getPageSize(){ Nck!z8
return pageSize; &C
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} %ZJ),9+
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publicvoid setPageSize(int pageSize){ K7)j
this.pageSize = pageSize; fhVbJU
} cq+nWHqF{J
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publicint getTotalCount(){ :u[
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return totalCount; DQL06`pX/
} !gD 3CA
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publicvoid setTotalCount(int totalCount){ ?,A}E|jZ
if(totalCount > 0){ ph}wnIW]
this.totalCount = totalCount; ;m2"cL>{l
int count = totalCount / n"K {uj))
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pageSize; V{ 4i$'
if(totalCount % pageSize > 0) F^/~@^{P
count++; H]T2$'U6
indexes = newint[count]; 4OqE.LFu
for(int i = 0; i < count; i++){ F&nMI:h7
indexes = pageSize * N3S,33
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} 5~<a>>
}else{ ~T;ajvJ
this.totalCount = 0; ~/]\iOL
} ;T"m[D
} :$X4#k<
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publicint[] getIndexes(){ @xW"rX#7f
return indexes; g:uaI
} Wq[=}qh~
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publicvoid setIndexes(int[] indexes){ )ZQ9a4%
this.indexes = indexes; /64^5DjTh
} 2yCd:wg
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publicint getStartIndex(){ RT_Pd\(qD
return startIndex; MK!]y8+Z
} x1 &b@u
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publicvoid setStartIndex(int startIndex){ U{za m
if(totalCount <= 0) ]y)R C-N
this.startIndex = 0; NdXy%Q
elseif(startIndex >= totalCount) X T)hPwg.
this.startIndex = indexes 8wH41v67F
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[indexes.length - 1]; B1i!te}*
elseif(startIndex < 0) EU&3Pdnd
this.startIndex = 0; {TxVRpiP{Z
else{ sgb+@&}9n
this.startIndex = indexes hAxuZb7 ?
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[startIndex / pageSize]; Oa_o"p<Lr
} 6GrMcI@hS
} t$PnQ@xu
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publicint getNextIndex(){ }T1Xds8w)t
int nextIndex = getStartIndex() + [&O:qaD^
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pageSize; - R8!"~o
if(nextIndex >= totalCount) 'i h
return getStartIndex(); fE7a]REK
else 2Ws/0c
return nextIndex; >.nt'BQ
} X%R^)zKV
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publicint getPreviousIndex(){ 51;%\@=
int previousIndex = getStartIndex() - Z$m2rZ#
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pageSize; 9{^B
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if(previousIndex < 0) (!&O4C5
return0; Fi3(glgd-
else t=pkYq5t8
return previousIndex; hb8@br
} 8wx#,Xa
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} RKJWLofX&
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抽象业务类 JA(q>>4
java代码: Z
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/** AJ1$$c
* Created on 2005-7-12 >_%g8T'
*/ Z
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package com.javaeye.common.business; (i~%4w=
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import java.io.Serializable; Mn{Rg>X
import java.util.List; +CHO0n
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import org.hibernate.Criteria; xupdjT%4
import org.hibernate.HibernateException; CvSG!l.6f<
import org.hibernate.Session; Hx/Vm`pRyX
import org.hibernate.criterion.DetachedCriteria; >0okb3+
import org.hibernate.criterion.Projections; L=Jk"qWV0
import E0x$;CG!
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org.springframework.orm.hibernate3.HibernateCallback; 0<Y&2<v
import Oua/NF)
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org.springframework.orm.hibernate3.support.HibernateDaoS G8c}re
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upport; ;+Kewi;<
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import com.javaeye.common.util.PaginationSupport; c oz}VMp
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public abstract class AbstractManager extends o|im
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HibernateDaoSupport { z4UQ:z@
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privateboolean cacheQueries = false; R20GjWy=
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privateString queryCacheRegion; *==nOO9G
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publicvoid setCacheQueries(boolean LBi>D`]
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cacheQueries){ srA~gzF
this.cacheQueries = cacheQueries; 74OM tLL$
} TzXl ?N
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publicvoid setQueryCacheRegion(String @_nhA/rlc
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queryCacheRegion){ Oz7v
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this.queryCacheRegion = Om~C0
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queryCacheRegion; d)sl)qt}0
} eci\Q,
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publicvoid save(finalObject entity){ nClU5
getHibernateTemplate().save(entity); S"z4jpqn3
} ".Ug
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publicvoid persist(finalObject entity){ (*gpa:Sc
getHibernateTemplate().save(entity); o(qmI/h
} 1 j8,Zrg1
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publicvoid update(finalObject entity){ ,#haai(
getHibernateTemplate().update(entity); 4 XQ?By
} jm"xf7
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publicvoid delete(finalObject entity){ LlqhZetS
getHibernateTemplate().delete(entity); n]!H,Q1,T
} =;T[2:JUu
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publicObject load(finalClass entity, Q0-~&e_'
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finalSerializable id){ NKrk*I"G
return getHibernateTemplate().load Lf9h;z>#
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(entity, id); #>'0C6Xn
} uy~j$ lrn
@ XMC$s
publicObject get(finalClass entity, c,^-nH'X>
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finalSerializable id){ %h rR'*nG
return getHibernateTemplate().get x1h!_^(QfF
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(entity, id); 8iRQPV-"_
} \D=B-dREq
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publicList findAll(finalClass entity){ ,D1QJPM
return getHibernateTemplate().find("from dWA7U6c<
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" + entity.getName()); hSmM OS{
} _DQdo
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publicList findByNamedQuery(finalString \JchcQ
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namedQuery){ 2bmppDk
return getHibernateTemplate ,ic}
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().findByNamedQuery(namedQuery); :([,vO:
} =0S7tNut
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publicList findByNamedQuery(finalString query, #,sJd ^uI
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finalObject parameter){ O1A*-G:X
return getHibernateTemplate Vufw:}i+^
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().findByNamedQuery(query, parameter); HhO$`YZ%>
} Tn|reXc0e
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publicList findByNamedQuery(finalString query, R)v`ZF,/b
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finalObject[] parameters){ f'
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return getHibernateTemplate p w,.*N3P
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().findByNamedQuery(query, parameters); <"-sN
} <NUZPX29
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publicList find(finalString query){ ,xiRP$hGhh
return getHibernateTemplate().find ny}?+&K
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(query); W{%M+a[#l
} Y\rKw!u_!
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publicList find(finalString query, finalObject Sdn]
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parameter){ }.Ug`7%G
return getHibernateTemplate().find U|>Js!$
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(query, parameter); yO !*pC
} x@/!H<y
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public PaginationSupport findPageByCriteria (Lc%G~{
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(final DetachedCriteria detachedCriteria){ 3KqylC&.
return findPageByCriteria L
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;;2s{{(R
} )t|M)z J
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public PaginationSupport findPageByCriteria myPo&"_ x
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(final DetachedCriteria detachedCriteria, finalint Wg#>2)>
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startIndex){ >B iJ/[9
return findPageByCriteria m49)c K?
n|8fdiK#}
(detachedCriteria, PaginationSupport.PAGESIZE, |d{4_o90
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startIndex); s8R.?mhH=
} 0Rj_l:d=
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public PaginationSupport findPageByCriteria Ygg+*z
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(final DetachedCriteria detachedCriteria, finalint %kF6y_h`
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pageSize, At"@`1n_u'
finalint startIndex){ xgfK0-T|[
return(PaginationSupport) SI-s:%O
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getHibernateTemplate().execute(new HibernateCallback(){ KZ&{Ya
publicObject doInHibernate 1X]?-+',.
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(Session session)throws HibernateException { <&B)i\j8=b
Criteria criteria = Zhf+u
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detachedCriteria.getExecutableCriteria(session); c1c8):o+V
int totalCount = n%A)#AGGc
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((Integer) criteria.setProjection(Projections.rowCount 2Lm.;l4YO
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()).uniqueResult()).intValue(); |%Pd*yZA
criteria.setProjection %qNT<>c
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(null); eX>x
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List items = 5*C#~gd&F
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criteria.setFirstResult(startIndex).setMaxResults (/JiOg^cw
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(pageSize).list(); ]sB-}n)
PaginationSupport ps = s9X?tWuL
,:;ZzHzR0
new PaginationSupport(items, totalCount, pageSize, yJNQO'wcv
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startIndex); B^nE^"b
return ps; opc`n}Fc
} ?NWc3 .
}, true); j"1#n? 0
} *>
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public List findAllByCriteria(final b@`h]]~:
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DetachedCriteria detachedCriteria){ #TS:|=
return(List) getHibernateTemplate "n'kv!?\
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().execute(new HibernateCallback(){ ^ZP
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publicObject doInHibernate -?nr q <3
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(Session session)throws HibernateException { "RcNy~
Criteria criteria = z[|2od
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detachedCriteria.getExecutableCriteria(session); 17la/7l<
return criteria.list(); ^pwT8Bp
} 5v5)vv.kd
}, true);
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} Nk2n&(~$
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public int getCountByCriteria(final 4]G J+a
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DetachedCriteria detachedCriteria){ vj%3v4
Integer count = (Integer) u43W.4H13
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getHibernateTemplate().execute(new HibernateCallback(){ ghU~H4[x D
publicObject doInHibernate ?mwa6]
{;5\ #VFg
(Session session)throws HibernateException { ghGpi U$
Criteria criteria = BD,J4xH;
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detachedCriteria.getExecutableCriteria(session); k:[T#/;
return fDjJdRS"
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criteria.setProjection(Projections.rowCount ?[?;%Y
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()).uniqueResult(); 2Q=I`H_
} T].Xx`
}, true);
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return count.intValue(); /Bq4! n+
} (&MtK1;;
} 1R,SA:L$
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用户在web层构造查询条件detachedCriteria,和可选的 m*|G2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ZZ>F ^t
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PaginationSupport的实例ps。 :.=#U
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ps.getItems()得到已分页好的结果集 _Un*x5u2O
ps.getIndexes()得到分页索引的数组 c+{ ar^)*
ps.getTotalCount()得到总结果数 V%'' GF
ps.getStartIndex()当前分页索引 !Qq~lAJO;
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 !t[;~`d9
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 1HLU
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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 Tol V3
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一下代码重构了。 +7{8T{
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我把原本我的做法也提供出来供大家讨论吧: <qVOd.9c
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首先,为了实现分页查询,我封装了一个Page类: ]E.\ |I(
java代码: mA#;6?6
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/*Created on 2005-4-14*/ }zIWagC6
package org.flyware.util.page; Tv `&
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/** 411z-aS
* @author Joa <E:_9#Z0sc
* - _~\d+>w
*/ 0KZ$v/m
publicclass Page { fymmAfaR
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/** imply if the page has previous page */ lt yhYPS
privateboolean hasPrePage; T+PERz(
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/** imply if the page has next page */ sX]gL
privateboolean hasNextPage; <?:h(IZe[
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/** the number of every page */ RU~Pa+H
privateint everyPage; R2Lq??XA=
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/** the total page number */ efuiFN;
privateint totalPage; I+`>e*:@W
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/** the number of current page */ T+S\'f\
privateint currentPage; eep/96G
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/** the begin index of the records by the current =@&>r5W1
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query */ >p`i6_P0P/
privateint beginIndex; t0za%q!fK<
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/** The default constructor */ 7jr+jNsowj
public Page(){
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} 9ph>4u(R
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/** construct the page by everyPage 3lKs>HE0
* @param everyPage U lCw{:#F
* */ r9<#R=r)}J
public Page(int everyPage){ : GFK
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this.everyPage = everyPage; Zqv
} -al
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/** The whole constructor */ I0;gTpt9
public Page(boolean hasPrePage, boolean hasNextPage, o)Px d
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int everyPage, int totalPage, -
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int currentPage, int beginIndex){ jw/@]f;N
this.hasPrePage = hasPrePage; :*R+ee,&-
this.hasNextPage = hasNextPage; G7KOJZb+D
this.everyPage = everyPage; L-m'
#
this.totalPage = totalPage; l*Fp}d.
this.currentPage = currentPage; P,7R/-u 5D
this.beginIndex = beginIndex; Tm0\Oue0
} -zZb]8\E
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/** BQv*8Hg
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* @return HcV,r,>e
* Returns the beginIndex. Mp^G7JY,
*/ [<}W S}
.
publicint getBeginIndex(){ _s:5)
return beginIndex; LaL{
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} !u/c'ZLZ>
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/** ,,g: x
* @param beginIndex 0Ca/[_
* The beginIndex to set. tItI^]w2s
*/ _^$F^}{&
publicvoid setBeginIndex(int beginIndex){ TXbi>t:/S{
this.beginIndex = beginIndex; cKIA.c}N
} sdKm@p|/|
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/** 1C/Vwf:@
* @return s-F3(mc(
* Returns the currentPage. [t*-s1cq
*/ 6kONuG7Yv
publicint getCurrentPage(){ Z5*O\kJv
return currentPage; _+Uf5,.5yU
} PpSQf14,
,8DjQz0ZPo
/** Ng*O/g`%L
* @param currentPage bOr6"nn
* The currentPage to set. d1NKVMeWr
*/ /1hcw|cfC
publicvoid setCurrentPage(int currentPage){ ir_X65l/2
this.currentPage = currentPage; TUQe.oAi
} K~qKr<)
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/** m'2EiYX$}\
* @return Q.fD3g
* Returns the everyPage. {!pYQ|#
*/ ei[, ug'
publicint getEveryPage(){ ko~e*31_E
return everyPage; Tq%##
} )<T2J0*
//#]CsFiP
/** 3IoN.
* @param everyPage LOk J
* The everyPage to set. '~x jaa;.
*/ hM8FN
publicvoid setEveryPage(int everyPage){ :eSwXDy&
this.everyPage = everyPage; Eq5X/Hx
} #
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}5u; '>$
/** X-SR0x
* @return jZ?^ |1
* Returns the hasNextPage. Rts}y:44
*/ wR9gx-bE
4
publicboolean getHasNextPage(){ (2/i1)Cq
return hasNextPage; ^ E3 HY@j
} eGI&4JgJ.
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/** -M-y*P)
* @param hasNextPage 1tH#QZIT
* The hasNextPage to set. ]iaQD _'\
*/ wtfM}MW\
publicvoid setHasNextPage(boolean hasNextPage){ q/3co86c
this.hasNextPage = hasNextPage; U,,rB(
} u6/;=]0
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/** qjIcRue'"
* @return ^ANz=`N5,
* Returns the hasPrePage. ,>I_2mc
*/ dkOERVRe
publicboolean getHasPrePage(){ #s-li b
return hasPrePage; !)uXCg9U
} z9^_5la#
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/** jHc/ EZB
* @param hasPrePage ~VJP:Y{[
* The hasPrePage to set. Jl89}Sf
*/ O9)k)A]`O
publicvoid setHasPrePage(boolean hasPrePage){ bt?)ryu
this.hasPrePage = hasPrePage; Jry643K>:;
} L9 H.DNA
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/** avH3{V
* @return Returns the totalPage. -o sxKT:
* uszMzO~
*/ R]_fe4Y0
publicint getTotalPage(){ 8j!(*'J.
return totalPage; X[o"9O|<
} n`7n5M*
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/** ZQrgYeQl"
* @param totalPage xqaw00,s
* The totalPage to set. |n.ydyu`
*/ 2N_9S?a3sK
publicvoid setTotalPage(int totalPage){ rDU"l{cg
this.totalPage = totalPage; x8*@<]!
} y1hJVYE2
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} zGE{Z A
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q"pnFK9/L
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 f= l*+QY8f
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个PageUtil,负责对Page对象进行构造: -qRO}EF
java代码: 1Du9N[2'P
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/*Created on 2005-4-14*/ hk1jxnQh
package org.flyware.util.page; JSm3ZP|GqJ
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import org.apache.commons.logging.Log; ^7~w yAr
import org.apache.commons.logging.LogFactory; >~^##bIb
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/** "t"&6\
* @author Joa b`sph%&
* }D eW2Jp
*/ Y_<(~eN`
publicclass PageUtil { Jv=G3=.
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privatestaticfinal Log logger = LogFactory.getLog mg^\"GC*8
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(PageUtil.class); mDp|EXN
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/** >h
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* Use the origin page to create a new page L&nGjC+Lr
* @param page sIJ37;ZA
* @param totalRecords 8h2! 8'
* @return 6Pa
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*/ d.&~n`Rv!p
publicstatic Page createPage(Page page, int BO p&s>hI
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totalRecords){ XJ;JDch
return createPage(page.getEveryPage(), XDJQO /qN
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page.getCurrentPage(), totalRecords); <!vAqqljt
} g3%t+>$*
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/** 9bT,=b;
* the basic page utils not including exception z
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^ffh
handler FBPT@`~v
* @param everyPage -3r&O:
* @param currentPage F#^ .L|d4
* @param totalRecords VMW?[j
* @return page T`=N^Ca1!`
*/ BI=Ie?
publicstatic Page createPage(int everyPage, int gGU3e(!Uc
d}',Bl+u{$
currentPage, int totalRecords){ &w3LMOT
everyPage = getEveryPage(everyPage); R#bg{|
currentPage = getCurrentPage(currentPage); $hO8
S =
int beginIndex = getBeginIndex(everyPage, <96ih$5D1
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currentPage); nZN]Q9
int totalPage = getTotalPage(everyPage, ki^[~JS>'
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totalRecords); 7w{`f)~
boolean hasNextPage = hasNextPage(currentPage, G$4lH>A&
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totalPage); ( L RX
boolean hasPrePage = hasPrePage(currentPage); $X~=M_W
&H5
6mL{
returnnew Page(hasPrePage, hasNextPage, fC%;|V'Nd
everyPage, totalPage, qg6Hk:^r
currentPage, sS(^7GARa
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beginIndex); `U`Z9q5-
} G68N@g
W.:kE|a.g
privatestaticint getEveryPage(int everyPage){ G';oM;~/|
return everyPage == 0 ? 10 : everyPage; iJrscy-
} +bf%]
+S%@/q
privatestaticint getCurrentPage(int currentPage){ b<.+WkO
return currentPage == 0 ? 1 : currentPage; S%xGXmZ
} KS(T%mk\
!FpMO`m
privatestaticint getBeginIndex(int everyPage, int Bdbw!zRR$
EUna_ 4=
currentPage){ @1Zf&'/6
return(currentPage - 1) * everyPage; 4VU5}"<
} J?%D4AeS]v
J;T_9
privatestaticint getTotalPage(int everyPage, int 5K6_#g4"
053W2Si
totalRecords){ x-Mp6
int totalPage = 0; [[s k
\v-> '
if(totalRecords % everyPage == 0) J$WIF&*0@
totalPage = totalRecords / everyPage; A<.Q&4jb
else /{kyjf[o&*
totalPage = totalRecords / everyPage + 1 ; HZK0Ldf
am"/Anml|
return totalPage; TyBNRnkt
} e&0B4wVAQ
+j@|D@z
privatestaticboolean hasPrePage(int currentPage){ }lxvXVc{I
return currentPage == 1 ? false : true; |[{;*wtv
} U<6k!Y9ny
|y:DLsom?i
privatestaticboolean hasNextPage(int currentPage, E$ngmm[
`jZX(H
int totalPage){ G8;S`-D1a,
return currentPage == totalPage || totalPage == 2Qy!Aa
=V,'f
0 ? false : true; Zi[)(agAT
} (bo bKr
Maa.>2v<
q;>BltU
} @Op8^8$`
V.-?aXQ *
OUdeQO?
Qrt8O7&('
5~44R@`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 9e1 6 g
7GIv3Dc
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ROjjN W`W
-DuiK:mp
做法如下: .y0](
h
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #P4dx'vm
Y(:OfC?
的信息,和一个结果集List: G^(&B30V
java代码: v|/3Mi9mz
fM|g8(TK,
eB\r/B]
/*Created on 2005-6-13*/ z\E"={P&
package com.adt.bo; F889JSZ%
Xou#38&p>
import java.util.List; 28)TXRr-
kR6 t
.
import org.flyware.util.page.Page; "~(&5M\8`
-oZac
/** vl5n%m H>^
* @author Joa kdUGmR0d
*/ B![5+
publicclass Result { fD~!t 8J
L@z !,r,
private Page page; rq1kj 8%2
'<0q"juXE
private List content; _M&.kha
p\{+l;`
/** {IMzR'PN
* The default constructor FR}H$R7#
*/ UC1!J
=f
public Result(){ reA8=>b/
super(); ?:?4rIZ<
} }R1`ThTM
Y/S3)o
/** X}*o[;2G
* The constructor using fields y^AA#kk
* O8r"M8
* @param page <c ovApx
* @param content Idlu1g
*/ CJ?gjV6
public Result(Page page, List content){ \ZFQ?e,d
this.page = page; %]ayW$4
this.content = content; pIu H*4Vz
} z/KZ[qH\
B"PHJj
/** ~9?U_ahfVt
* @return Returns the content. }Hz-h4Z
*/ Q==v!"Gi|
publicList getContent(){ RW7oL:$dt
return content; rh`.$/^
} "F"_G
u`pROd/ R5
/** 0sd-s~;
* @return Returns the page. b%;59^4AjD
*/ OF&h=1De,
public Page getPage(){ |.C
return page; fT3*>^Uv
} g?~ Tguv
YvruK:I
/** tQ~<i %;
* @param content nnE_OK!}T
* The content to set. |:9Ir^
*/ HRV*x!|I
public void setContent(List content){ 8*yo7q&
this.content = content; R|1xXDLm*E
} (
f,J_
=#(0)p$EC
/** rQEi/
* @param page )_8}53C
* The page to set. ^IGyuj0]jG
*/ poD\C;o"
publicvoid setPage(Page page){ \E@s_fQ]
this.page = page; Ka]@[R6e
} P>Q{He:
} 5r4gmy>
PXosFz~
's[BK/
=3|pHc hJ4
A)hhnb0o
2. 编写业务逻辑接口,并实现它(UserManager, JoCA{Fa}
d=XpO*v,[
UserManagerImpl) %X4-a%512
java代码: 7]|zkjgI
fw' r.
cJ(BiL-uF
/*Created on 2005-7-15*/ @P:R~m2
package com.adt.service; ?MC(}dF0
B6bOEPQ
import net.sf.hibernate.HibernateException; ~uI**{
6F`qi:a+
import org.flyware.util.page.Page; 3ai (x1%
Gg%tVQu
import com.adt.bo.Result; LJGJ|P
<%z@
/** J&eAL3"GF
* @author Joa ~G>jw"r
*/ '>3`rsu
publicinterface UserManager { Ge~q3"
5W+{U8\
public Result listUser(Page page)throws =<{h^-j;a
n]+.
HibernateException; EeCFII
+YTx
} Xv0F:1
McjS)4j&.
x>%joKY[
2 H[ ; v +
Dl%?OG<
java代码: M% @
Xo Y7/&&
3gpo
%
/*Created on 2005-7-15*/ HsnG4OE
package com.adt.service.impl; Ikj=`,a2B
Fn!SGX~kx$
import java.util.List;
EX:{EmaT
&<Mt=(qY1
import net.sf.hibernate.HibernateException; jYWw.g<
I!0JG`&
import org.flyware.util.page.Page; 'M8aW!~
import org.flyware.util.page.PageUtil; cZ|lCy^
lkA^\+Ct
import com.adt.bo.Result; 3_W{T@T
import com.adt.dao.UserDAO; IaLMWoh
import com.adt.exception.ObjectNotFoundException; D`VFf\7
import com.adt.service.UserManager; Ky kSFB
nUc;/
/** ;i\C]*
* @author Joa rjUBLY1(
*/ QR"bYQ
publicclass UserManagerImpl implements UserManager { !v9lk9SV
~*}$>@f{[X
private UserDAO userDAO; >)Gd:636+
6Y1J2n"
/** vXdZmYrC
* @param userDAO The userDAO to set. \9)#l#m
*/ / p)F>WR
publicvoid setUserDAO(UserDAO userDAO){ )KY:m |Z
this.userDAO = userDAO; 8o|P&q(v*
} `T"rG}c
I@\+l6&#;
/* (non-Javadoc) ,l HLH
* @see com.adt.service.UserManager#listUser 7,'kpyCj
-(#-I$z
(org.flyware.util.page.Page) s;Y<BD
*/ uS<_4A;sD,
public Result listUser(Page page)throws XE rUS80
dMvp&M\\'
HibernateException, ObjectNotFoundException { U
O<:.6"
int totalRecords = userDAO.getUserCount(); !aNh!
if(totalRecords == 0) uzBz}<M=
throw new ObjectNotFoundException WVX`<
gU1 #`r>[)
("userNotExist"); 3fr ^ T
page = PageUtil.createPage(page, totalRecords); `rb>K
List users = userDAO.getUserByPage(page); }Qr6l/2
returnnew Result(page, users); Br5o7(AE
} &@v<nO-
{0v*xL_O^
} +(?>-3_z
H?` g!cX
s B
20/F
S%mfs!E>
nFM@@oA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 sL^yB
0Scm?l3
询,接下来编写UserDAO的代码: |/`%3'4H
3. UserDAO 和 UserDAOImpl: 'Ot,H_pE
java代码: D'_Bz8H!p
r&3pM2Da}
w?y6nTg<
/*Created on 2005-7-15*/ uQqWew8l+
package com.adt.dao; r8/l P}(F
NHQF^2 \\
import java.util.List; G"dS+,Q
(Ddp|a"b
import org.flyware.util.page.Page; K^[#]+nQ
4QHS{tj
import net.sf.hibernate.HibernateException; /JJw 6[N
_5Bcwa/
/** g);^NAA
* @author Joa \2C`<h$fN
*/ {QAv~S>4
publicinterface UserDAO extends BaseDAO { TbvtqM 0
=aG xg57
publicList getUserByName(String name)throws G$M9=@Ug
GW^,g@%C
HibernateException; m#!=3P7T
'jg3
publicint getUserCount()throws HibernateException; `#P$ ]:
&a0r%L()X
publicList getUserByPage(Page page)throws U(>4s]O6
o{:xp r=(
HibernateException; ,:2'YB
`)iY}Iu
} yay<GP?
xw5d|20b
K5>p89mZ
21X`h3+=
DOS0;^f
java代码: }L=/A7Nk>
LpbsYl
<W8t|jt
/*Created on 2005-7-15*/ z;tI D~Y
package com.adt.dao.impl; `4?~nbz
CqMhk
import java.util.List; z4%uN|V
yF}OfK?0f
import org.flyware.util.page.Page; K7knK
Kb#4ILA
import net.sf.hibernate.HibernateException; E51dV:l
import net.sf.hibernate.Query; f
3V Dv9(
7"F*u :
import com.adt.dao.UserDAO; ia&AW
jdZ~z#`(!:
/** aimarU
* @author Joa 8
;d$54
b
*/ r`y ezbG
public class UserDAOImpl extends BaseDAOHibernateImpl NL=|z=q
{N2g8W:
implements UserDAO { W:,4 :|3
,u }XWV
/* (non-Javadoc) 5,qj7HZF
* @see com.adt.dao.UserDAO#getUserByName +y7;81ND
'FlJpA}
(java.lang.String) 4'j
sDcs
*/ jUv!9Y}F
publicList getUserByName(String name)throws Ds#/
2]GdD*
HibernateException { P./V6i<:
String querySentence = "FROM user in class X'. qYsS
\P} p5k[
com.adt.po.User WHERE user.name=:name"; _{t9 x\=
Query query = getSession().createQuery 7{e{9QbJ4
#_lt~^6
(querySentence); D']ZlB'K
query.setParameter("name", name); ]2#
return query.list(); T2}FYVj?!g
} ?88[|;b3
]{"Br$
/* (non-Javadoc) 'O5'i\uz
* @see com.adt.dao.UserDAO#getUserCount() vS\%3A4^+5
*/ L;gO;vO
publicint getUserCount()throws HibernateException { CTWn2tpW
int count = 0; ]\/tVn.'
String querySentence = "SELECT count(*) FROM SH*C"
`D9]*c
!mO
user in class com.adt.po.User"; 6KD `oUx
Query query = getSession().createQuery 0|R# Tb;Y
F+ E|r6'i
(querySentence); KD/V aN
count = ((Integer)query.iterate().next R[49(>7H4
"ZTTg>r
()).intValue(); Z%I
return count; 4w#``UY)'
} 2o>)7^9|#<
>^Se'SE]
/* (non-Javadoc) jV(6>BAI_
* @see com.adt.dao.UserDAO#getUserByPage \~LQ%OM
JG9` h#
(org.flyware.util.page.Page) kId
n6 Wx,
*/ e/->_T(I
publicList getUserByPage(Page page)throws 3Tn)Z1o
##Z_QB(;
HibernateException { w8g,a]p
String querySentence = "FROM user in class ]xguBh ]
qc#)!
com.adt.po.User"; *^([ ~[
Query query = getSession().createQuery `/HUV&i"S
DJP2IP
(querySentence); }K8/-d6
query.setFirstResult(page.getBeginIndex()) K}=|.sE9
.setMaxResults(page.getEveryPage()); ICAH G7 ,
return query.list(); 5OoN!TEM
} u_7~TE3W
%*#n d
} Ela-,(Glk
U%h);!<
}E`dZW*!!
\,J/ r!
191&_*Xb
至此,一个完整的分页程序完成。前台的只需要调用 QXF
aAb=(7
Fu^^i&
userManager.listUser(page)即可得到一个Page对象和结果集对象 A>{p2?`+!
a,78l@d(
的综合体,而传入的参数page对象则可以由前台传入,如果用 5s{ABJ\@V
"bDs2E+W
webwork,甚至可以直接在配置文件中指定。 w&xDOyW]
YDGS}~m~Q
下面给出一个webwork调用示例: N41 R
java代码: kD[ r.Dma
waKT{5k
KRjV}\}
/*Created on 2005-6-17*/ +nQw?'9Z
package com.adt.action.user; WW~+?g5
G<M:Ak+~
import java.util.List; h[Gg}N!
&CwFdx:Ff
import org.apache.commons.logging.Log; D/h/Y) Y
import org.apache.commons.logging.LogFactory; c^`]`xiX
import org.flyware.util.page.Page; m~uOXb
jF[ 1za
import com.adt.bo.Result; v`1,4,;,qs
import com.adt.service.UserService; |pa$*/!NT
import com.opensymphony.xwork.Action; fL]Pztsk+
O0>A+o[1F
/** wW>)(&!F
* @author Joa WL{(Ob
*/ Ngg?@pG0y
publicclass ListUser implementsAction{ ;l$ \6T
'EFyIVezg9
privatestaticfinal Log logger = LogFactory.getLog qF iLh9=D
(LHp%LaZ\;
(ListUser.class); jjM{]
;Eec5w1
private UserService userService; q64k7<C,
B^%1Rpcn
private Page page; &QNWL]
sdCvG R e
privateList users; y$<Vha
Y
wkyq>Rv
/* 7OWbAu;
* (non-Javadoc) -)vEWn$3<
* NzKUtwnIz
* @see com.opensymphony.xwork.Action#execute() |j3'eW&=
*/ WL+]4Wiz
publicString execute()throwsException{ Z0De!?ALV\
Result result = userService.listUser(page); kM`l
page = result.getPage(); @E.k/G!~Nb
users = result.getContent(); s_.]4bl.8
return SUCCESS; m?HZ;
} 6!^[];%xN
Ap{}^
/** <}6{{&mT4
* @return Returns the page. `"@ X.}\
*/ U}SXJH&&E
public Page getPage(){ y0~Ia:y
return page; a^5^gId5l!
} g]UBZ33y
fFjH "2WD
/** Z`3ufXPNlO
* @return Returns the users. 0ult7s}
*/ .}')f;jH5<
publicList getUsers(){ i*R,QN)
return users; H&b3{yOa
} 2wqk,c[]
YC]L)eafo`
/** `bKA+c,f
* @param page drwgjLC+
* The page to set. @5)
8L/[l
*/ l8K5k:XCU3
publicvoid setPage(Page page){ JN6-Z2
this.page = page; P\CDd=yWc
} @xsCXCRWVV
I &* _,d
/** PN+G:Qv
* @param users +MK6zf
* The users to set. ~8`:7m?
*/ %=j3jj[
publicvoid setUsers(List users){ !2:3MbtR
this.users = users; zq5'i!s !0
} U-wLt(Y<
O?EB8RB
/** h x6;YV
* @param userService *s}|Hy
* The userService to set. CBf7]n0H
*/ zBf-8]"^
publicvoid setUserService(UserService userService){ RnfXN)+P
this.userService = userService; *5$&`&,
} \F, DA"K_
} iV.p5FD
6)]f6p&e
0h$GI"dR
64Gi8|P
#y]3LC#)^G
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, T)7TyE|"2g
/.5;in
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 jn9 ShF
2=PBxDs;
么只需要: DJhb
java代码: |P6EO22p
MQ][mMM;w
s_jBu
<?xml version="1.0"?> Iy
{U'a!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork iZ[tHw||
NnxM3*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- "C%!8`K{a*
]0c Pml
1.0.dtd"> %IpSK 0<Sp
'Tb0-1S?
<xwork> >', y
.BTx&AqU
<package name="user" extends="webwork- |U[y_Y\a
`!\ivIi^
interceptors"> a
ib}`l
G2mNm'0
<!-- The default interceptor stack name %/0gWG
5{>0eFzG
--> Z$K+
7>^
<default-interceptor-ref ]S8LY.Az5
yYAnwf
name="myDefaultWebStack"/> 0V11#
?)A2Kw>2
<action name="listUser" rFag@Z"["
]H 2R
class="com.adt.action.user.ListUser"> xi {|
<param H$!-f>Rxa
;cSGlE |
name="page.everyPage">10</param> m% bE-#
<result Md(JIlh3
5 Rz/Ri\c=
name="success">/user/user_list.jsp</result> =mrY/:V
</action> HY;oy(
;bHfn-X
</package> o<4D=.g7D
A|vP$zy
</xwork> n! .2aq
>_Uj?F:
Jirct,k
{vfq
HCc`
gg8c7d: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 ce5nG0@#
d7~j^v)=^
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。 R<&FhT]
)1_(>|@oi
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 W(k:Pl#
xURw,
a>b8-j=J
_'c+fG
\
8IWwjyRr
我写的一个用于分页的类,用了泛型了,hoho rbh[j@s@
;5M<j3_*
java代码: t-lv|%+8
(UzPkl kZ
F"BL#g66
package com.intokr.util; ,Oi^ySn
IO[^z
v4F
import java.util.List; n#>5?W
V Cf|`V~ G
/** {&`VGXG
* 用于分页的类<br> L1MrrC
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ('HxHOh2
* ]^!}*
* @version 0.01 \1{_lynD
* @author cheng #7C6yXb%
*/ L<E/,IdE
public class Paginator<E> { ;Xh5oB\)W
privateint count = 0; // 总记录数 ++k J\N{
privateint p = 1; // 页编号 \>;%Ji
privateint num = 20; // 每页的记录数 z`@z
privateList<E> results = null; // 结果 hg#c[sZL
)]}$
/** dgY5ccP
* 结果总数 I9,8HtnA
*/ JilKZQmk
publicint getCount(){ ]0YDb~UB
return count; ]gHLcr3
} h{H]xe[Q
fr]Hc+7
publicvoid setCount(int count){ wNR=?Z~
this.count = count; Hi7G/2t@`
} %\l0-RA@<
rxArTpS{.#
/** dL(4mR8
* 本结果所在的页码,从1开始 .Map
* y0y+%H-
* @return Returns the pageNo. O E]~@eU
*/ (Otur
publicint getP(){ YiO3<}Uf
return p; R1~7F{FW
} ',%5mF3j
s1v{~xP
/** <@%ma2
* if(p<=0) p=1 ]svw
CPu C
* + f 6}p
* @param p .$OjUlzr-H
*/ .GtINhz*
publicvoid setP(int p){ @}Pw0vC
if(p <= 0) `}ZL'\G
p = 1; np= J:v4
this.p = p; ={OCa1
} pM,#wYL
a3*.,%d
/** "^!j5fZ
* 每页记录数量 -IGMl_s
*/ &