Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 w~A{(-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &MQmu,4
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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 e7Z32P0ls
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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 [< ?s?Ci
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分页支持类: 2DtM20<>
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java代码: Egp/f|y
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package com.javaeye.common.util; oy=js -
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import java.util.List; ?
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publicclass PaginationSupport { ,t?B+$E
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publicfinalstaticint PAGESIZE = 30; mbxZL<ua
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privateint pageSize = PAGESIZE; 9gDkTYkj
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privateList items; jyUjlYAAv`
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privateint totalCount; 3g,`.I_
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privateint[] indexes = newint[0]; :Zbg9`d*
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privateint startIndex = 0; ,{u
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public PaginationSupport(List items, int .m,_N@,
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totalCount){ 3vN_p$
setPageSize(PAGESIZE); ^R7lom.
setTotalCount(totalCount); rdP[<Y9
setItems(items); ]Ji.Zk
setStartIndex(0); 'Ym9;~(@R
} vXf!G`D
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public PaginationSupport(List items, int t7Iv?5]N
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totalCount, int startIndex){ v6bGjVK[
setPageSize(PAGESIZE); uK"=i8rs4
setTotalCount(totalCount); !Vn\u
setItems(items); ghG**3xr
setStartIndex(startIndex); {j?FNOJn
} xQ-<WF1i
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public PaginationSupport(List items, int $aDVG})
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totalCount, int pageSize, int startIndex){ (ylTp]~mR-
setPageSize(pageSize); {9&;Q|D z
setTotalCount(totalCount);
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setItems(items); i(%W_d!
setStartIndex(startIndex); mZS
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} kX7C3qdmt
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publicList getItems(){ nLZTK&7}
return items; UT~4x|b:O
} [I,Z2G,Jb
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publicvoid setItems(List items){ .Ni\\
this.items = items; S"bg9o
} NdA[C|_8}f
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publicint getPageSize(){ y1eWpPJa
return pageSize; 3</_c1~
} [2!w_Iw'
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publicvoid setPageSize(int pageSize){ *e TqVG.
this.pageSize = pageSize; X"|['t
} '6iEMg&3
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publicint getTotalCount(){ jjB~G^n
return totalCount; h,u,^ r
} O~#!l"0 L+
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publicvoid setTotalCount(int totalCount){ gZ3u=uME
if(totalCount > 0){ Xv5wJlc!d
this.totalCount = totalCount; D[[|")Fn
int count = totalCount / r"gJX
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pageSize; p?%y82E
if(totalCount % pageSize > 0) P:K5",)
count++; Y1W1=Uc uk
indexes = newint[count]; urs,34h
for(int i = 0; i < count; i++){ .LnGL]/
indexes = pageSize * q.^;!f1
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} i4Q@K,$
}else{ O'p9u@kc
this.totalCount = 0; 5,lEx1{_
} hP%M?MKC
} *MFIV02[N
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publicint[] getIndexes(){ Tj`,Z5vy
return indexes; >-RQ]?^
} 6RU~"C
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publicvoid setIndexes(int[] indexes){ )5Q~I,dP
this.indexes = indexes; YlJ@XpKM
} lV3x *4O=
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publicint getStartIndex(){ Fc)@,/R"v
return startIndex; \g`\`e53?
} d=$Mim
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publicvoid setStartIndex(int startIndex){ ~k-y &<UR
if(totalCount <= 0) T*/rySs
this.startIndex = 0; XB;7!8|
elseif(startIndex >= totalCount) 6m/r+?'
this.startIndex = indexes U/66L+1
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[indexes.length - 1]; 13$%,q)
elseif(startIndex < 0) u
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this.startIndex = 0; hlvK5Z
else{ i(rL|d+'
this.startIndex = indexes >;aWz%-
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[startIndex / pageSize]; n:I,PS0H<
} c)6m$5]
} ^KnU4sD
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publicint getNextIndex(){ kUL'1!j7
int nextIndex = getStartIndex() + RtkEGxw*^
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pageSize; zJKv'>?
if(nextIndex >= totalCount) /Iu1L#
return getStartIndex(); P[G)sA_"
else kf\PioD8
return nextIndex; l?v86k
} b"<liGh"n-
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publicint getPreviousIndex(){ T8?Ghbn
int previousIndex = getStartIndex() - 0mYXv4
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pageSize; P8OaoPj
if(previousIndex < 0) fh&nu"&
return0; yM6pd U]i
else n K1Slg#U
return previousIndex; >mbHy<<
} a Yg6H2Un
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} V@.Ior}w
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抽象业务类 ozyX$tp
java代码: <`8n^m*
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/** W<h)HhyG
* Created on 2005-7-12 k&M;,e3v6
*/ {r,.!;mHu
package com.javaeye.common.business; ]? c
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import java.io.Serializable; ydEoC$?0
import java.util.List; xWH.^o,"
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import org.hibernate.Criteria; >F|>cc>_E
import org.hibernate.HibernateException; 6$hQ35
import org.hibernate.Session; M5LfRBO
import org.hibernate.criterion.DetachedCriteria; ~gJwW+
import org.hibernate.criterion.Projections; [Q~#82hBhY
import C#.->\
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org.springframework.orm.hibernate3.HibernateCallback; i'<[DjMDlm
import 9Z$"K- G
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org.springframework.orm.hibernate3.support.HibernateDaoS \{_q.;}
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upport; q_: 4w$>
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import com.javaeye.common.util.PaginationSupport; Qab>|eSm
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public abstract class AbstractManager extends -u+vJ6EY
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HibernateDaoSupport { df8k7D;~e
l ~"^7H?4e
privateboolean cacheQueries = false; 3GYw+%Z]
@(w@e\Bq
privateString queryCacheRegion; {f_={k
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publicvoid setCacheQueries(boolean 5+4IN5o]=
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cacheQueries){ /obfw^
this.cacheQueries = cacheQueries; a@K%06A;'
} @Rze|
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publicvoid setQueryCacheRegion(String V;VHv=9`o
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queryCacheRegion){ 94`7a<&ZNL
this.queryCacheRegion = LtF,kAIt7v
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queryCacheRegion; @}u*|P*
} h%na>G
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publicvoid save(finalObject entity){ c%
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getHibernateTemplate().save(entity); jxJ8(sr$
} >{n,L6_t
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publicvoid persist(finalObject entity){ IxN9&xa
getHibernateTemplate().save(entity); XAKs0*J>
} f1RWP@iar
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publicvoid update(finalObject entity){ 5J.bD)yrP
getHibernateTemplate().update(entity); #6aW9GO
} #<"~~2?
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publicvoid delete(finalObject entity){ BQHVQs
getHibernateTemplate().delete(entity); mkk6`,ov
} sRR(`0Zp
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publicObject load(finalClass entity, .[KrlfI
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finalSerializable id){ A/$QaB,x
return getHibernateTemplate().load J$DE"|-
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(entity, id); ij`w} V
} ea2ayT
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publicObject get(finalClass entity,
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finalSerializable id){ \fLMr\LL&
return getHibernateTemplate().get Igt#V;kK"2
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(entity, id); T@B/xAq5!
} U[-o> W#
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publicList findAll(finalClass entity){ H [\o RId
return getHibernateTemplate().find("from oG?Xk%7&\
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" + entity.getName()); 9wUkh}s
} <?.&^|kS
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publicList findByNamedQuery(finalString yjX9oxhtL
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namedQuery){ a(X@Q8l:
return getHibernateTemplate `UyG_;
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().findByNamedQuery(namedQuery); FIhk@TKa
} /& {A!.;
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publicList findByNamedQuery(finalString query, *I.f1lz%*
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finalObject parameter){ `cUl7 'j
return getHibernateTemplate AM \'RHL
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().findByNamedQuery(query, parameter); :J@gmY:C
} +.[ <%
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publicList findByNamedQuery(finalString query, ]y'>=a|T
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finalObject[] parameters){ g3/W=~r
return getHibernateTemplate 83\pZ1>)_
} 9Eg=%0v
().findByNamedQuery(query, parameters); B%b4v
} u'DRN,h+
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publicList find(finalString query){ }@+0/W?\.
return getHibernateTemplate().find YnAm{YyI
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(query); VA_PvL.9
} }!r|1$,kL
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publicList find(finalString query, finalObject \'D0'\:vz
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parameter){ hx %v+/
return getHibernateTemplate().find Rtl"Ub@HV
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(query, parameter); `(V3:F("@
} q"J]%zO
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public PaginationSupport findPageByCriteria S`0(*A[W*
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(final DetachedCriteria detachedCriteria){ a~}OZ&PG
return findPageByCriteria 1};Stai'
9}<ile7^
(detachedCriteria, PaginationSupport.PAGESIZE, 0); <0&*9ZeD
} 5x4yyb'
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public PaginationSupport findPageByCriteria pJ"qu,w
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(final DetachedCriteria detachedCriteria, finalint P@Oo$ o
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startIndex){ Ckuh:bs
return findPageByCriteria cf20.F{<
7'V@+5
(detachedCriteria, PaginationSupport.PAGESIZE, u0c1:Uv#~e
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startIndex); 9IfmW^0
} 0gr/<v
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public PaginationSupport findPageByCriteria oIzj,v8$
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(final DetachedCriteria detachedCriteria, finalint ,f'CD{ E
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pageSize, 6}Ci>_i4#
finalint startIndex){ ag[wdoj
return(PaginationSupport) H=vUYz
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getHibernateTemplate().execute(new HibernateCallback(){ R"t,xM
publicObject doInHibernate WO>nIo5Y
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(Session session)throws HibernateException { @,my7?::oM
Criteria criteria = CxW>~O:
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detachedCriteria.getExecutableCriteria(session); T_5H&;a
int totalCount = e 2oa($9
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((Integer) criteria.setProjection(Projections.rowCount fxHH;hRfv
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()).uniqueResult()).intValue(); y/7\?qfTk
criteria.setProjection 8dIgjQX|
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(null); Ie#Bkw'*
List items = vr6w^&[c^
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criteria.setFirstResult(startIndex).setMaxResults "JV_ 2K_i
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(pageSize).list(); wc4{)qDE
PaginationSupport ps = `l[c_%Bm
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new PaginationSupport(items, totalCount, pageSize, !M1"b;
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startIndex); ;$wVu|&
return ps; !?h;wR
} >SHhAEF
}, true); ul >3B4
} z$. 88^
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public List findAllByCriteria(final n 0L^e
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DetachedCriteria detachedCriteria){ _Q 4)X)F
return(List) getHibernateTemplate dcN22A3
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().execute(new HibernateCallback(){ E]-/Zbvdv
publicObject doInHibernate >}i E(
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(Session session)throws HibernateException { JjTegQN
Criteria criteria = e6$W Qd`O
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detachedCriteria.getExecutableCriteria(session); \Uq(Zga4)
return criteria.list(); SoK
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} cR<fJ[*
}, true); BW*rIn<?G
} "@0]G<H
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public int getCountByCriteria(final /7^4O(iG
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DetachedCriteria detachedCriteria){ hhc,uJ">!
Integer count = (Integer) 7~.9=I'A
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getHibernateTemplate().execute(new HibernateCallback(){ ]&+s6{}
publicObject doInHibernate 3;]H1
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(Session session)throws HibernateException { +VOK%8,p
Criteria criteria = BUXpCxQ
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detachedCriteria.getExecutableCriteria(session); M%P:n/j
return )1`0PJoHE
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criteria.setProjection(Projections.rowCount JU&c.p
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()).uniqueResult(); 6mxfLlZ
} ; )@~
}, true); _F|Ek ;y%
return count.intValue(); `7V]y-
} 56kI
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} [5Mr@f4I
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用户在web层构造查询条件detachedCriteria,和可选的 0)Wltw~`&
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 X2~!(WxU F
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PaginationSupport的实例ps。 N2<!}Eyu
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ps.getItems()得到已分页好的结果集 i2SR{e8:GF
ps.getIndexes()得到分页索引的数组 5MJS
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ps.getTotalCount()得到总结果数 #BH*Z(
ps.getStartIndex()当前分页索引 `1IgzKL9
ps.getNextIndex()下一页索引 R`E ~ZWC4V
ps.getPreviousIndex()上一页索引 $c(nF01
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }9}h*RWm
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @?]RBX?a
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一下代码重构了。 RPL:-
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我把原本我的做法也提供出来供大家讨论吧: Vp@?^imL
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首先,为了实现分页查询,我封装了一个Page类: 3eQ&F~S
java代码: YNsJZnGr8#
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/*Created on 2005-4-14*/ NyNXP_8
package org.flyware.util.page; ' %o#q6O
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/** 8[{ Vu0R
* @author Joa @GW#&\yM
* sdw(R#GE
*/ =]0&i]z[.
publicclass Page { Se =`N
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/** imply if the page has previous page */ %6f*{G
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privateboolean hasPrePage; 3AN/
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/** imply if the page has next page */ smo~7;
privateboolean hasNextPage; B
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/** the number of every page */ toC^LZgZ_6
privateint everyPage; L)
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/** the total page number */ a<bwzX|.
privateint totalPage; T1=fNF
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/** the number of current page */ S;`A{Mow
privateint currentPage; Q>Yjy!.<^
VRB;$
/** the begin index of the records by the current ^s"R$?;h
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query */ I51@QJX
privateint beginIndex; NqWdRU
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/** The default constructor */ t;\Y{`
public Page(){ XU(eEnmom
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} o0KL5].
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/** construct the page by everyPage Oxd]y1
* @param everyPage 2g! +<YZ~
* */ j|#Bo:2km
public Page(int everyPage){ 9p(.A$
this.everyPage = everyPage; %._.~V
} H"WprHe
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/** The whole constructor */ Wvf
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public Page(boolean hasPrePage, boolean hasNextPage, C1QA)E['V
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int everyPage, int totalPage, 1yu4emye4
int currentPage, int beginIndex){ [` 7ThHX
this.hasPrePage = hasPrePage; mc\"yC^s
this.hasNextPage = hasNextPage; B^^#D0<
this.everyPage = everyPage; }-=|^
this.totalPage = totalPage; Uz]|N6`
this.currentPage = currentPage; YNi.SXH
this.beginIndex = beginIndex; vyI!]p
} }&D32\
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/** +52{-a,>
* @return -nV9:opD
* Returns the beginIndex. I
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*/ *0=j?~&
publicint getBeginIndex(){ W7nw6;7=
return beginIndex; ZPYS$Ydy
} tY4;F\e2|A
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/** fI|Nc
* @param beginIndex 4'=y:v2
* The beginIndex to set. Z4ImV~m
*/ $6poFo)U+
publicvoid setBeginIndex(int beginIndex){ f) L
this.beginIndex = beginIndex; )lDD\J7
} Mb*?5R6;
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/**
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* @return 8KzkB;=n
* Returns the currentPage. 13x p_j
*/ `VguQl_,gA
publicint getCurrentPage(){ Otn1wBI
return currentPage; =@~Y12o?%
} ^^ixa1H<
' S/gmn
/** fe_5LC"
* @param currentPage 3%b6{ie/=
* The currentPage to set. GnJt0 {
*/ G]&qx`TBK
publicvoid setCurrentPage(int currentPage){ @f3E`8
this.currentPage = currentPage; %d9uTm;
} Cq~dp/V
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/** \ @2R9,9E
* @return +ami?#Sz*;
* Returns the everyPage. ;Q`lNFa
*/ a0H+.W+]
publicint getEveryPage(){ 67FWa
return everyPage; 7WzxA=*#
} )zDCu`
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/** FGBbO\</
* @param everyPage Yrq~5)%
* The everyPage to set. PLBrP
*/ O*P.]d
publicvoid setEveryPage(int everyPage){ 5*u+q2\F
this.everyPage = everyPage; =>~:<X.,
} E|shs=I
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/** W ]8QM1$
* @return j8:\%|
* Returns the hasNextPage. Dk5 1z@
*/ 'i|YlMFI g
publicboolean getHasNextPage(){ <t!W5q
return hasNextPage; nKj7.,>;:<
} tw)mepwB
}3WxZv]I}
/** '[%j@PlCX
* @param hasNextPage cQ}{[YO
* The hasNextPage to set. +^F Zq$NP
*/ "qy,*{~
publicvoid setHasNextPage(boolean hasNextPage){ +k R4E23:
this.hasNextPage = hasNextPage; [AJJSd/:
} nQ3A~ ()
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/** 42ge3>
* @return ,64-1!
* Returns the hasPrePage. w7&A0M
*/ k$:|-_(w
publicboolean getHasPrePage(){ C\hM =%
return hasPrePage; TIg3`Fon
} B^}yo65I
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/** v4 E}D
* @param hasPrePage 6Q5^>\Y
* The hasPrePage to set. @_{=V0
*/ ?:eV%`7
publicvoid setHasPrePage(boolean hasPrePage){ ;5( UzQU
this.hasPrePage = hasPrePage; %^6F_F_jS
} {?7Uj
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/** 0JujesUw(
* @return Returns the totalPage. Zx>=tx}
* \o3gKoL%
*/ M X]n&
publicint getTotalPage(){ KwVbbC3
return totalPage; t"I77aZ$A
} V>3X\)qu
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/** )0k53-h&
* @param totalPage Lu%b9Jk
* The totalPage to set. G=bCNn<
*/ [()koU#w.
publicvoid setTotalPage(int totalPage){ 7F.4Ga;
this.totalPage = totalPage; %A0/1{(
} ql~J8G9
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} e&>2
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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 |JsZJ9W+J
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个PageUtil,负责对Page对象进行构造: KqP#6^ _
java代码: 4Wp=y
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/*Created on 2005-4-14*/ 9:lFo=
package org.flyware.util.page; -trkA'ewZ
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import org.apache.commons.logging.Log; 0<*<$U
import org.apache.commons.logging.LogFactory; Vi|#@tC'
wb ;xRP"w
/** qmP].sA
* @author Joa 1=v*O.XW`
* =-Ck4e *T
*/ 62NsJ<#>
publicclass PageUtil { PQE=D0
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privatestaticfinal Log logger = LogFactory.getLog 2B`JGFcdcB
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(PageUtil.class); `EQL" =)
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/** 8RHUeRX
* Use the origin page to create a new page "9807OME
* @param page D)}v@je"yP
* @param totalRecords MpOc
* @return ]I6 J7A[
*/ 0tJZ4(0
publicstatic Page createPage(Page page, int _t ycgq#
BFt> 9x]T
totalRecords){ o#N+Y?O
return createPage(page.getEveryPage(), @'|~v<<WZ
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page.getCurrentPage(), totalRecords); J9 I:Q<;
} YchH~m|
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/** {\\Tgs
* the basic page utils not including exception U%/+B]6jP
-ze J#B)C
handler R^e'}+Z
* @param everyPage K.yb
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* @param currentPage MUwMb!Z.s
* @param totalRecords onV>.7sG
* @return page Fs^Mw
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*/ MfkN]\Jyw
publicstatic Page createPage(int everyPage, int kSo"Ak!
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currentPage, int totalRecords){ bs1Rvx1:J%
everyPage = getEveryPage(everyPage); ;9'OOz|+1
currentPage = getCurrentPage(currentPage); . 'yCw#f
int beginIndex = getBeginIndex(everyPage, $`'/+x"%
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currentPage); OB}Ib]
int totalPage = getTotalPage(everyPage, yF/j Fn
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totalRecords); BLJj(-
boolean hasNextPage = hasNextPage(currentPage, wS3'?PRX
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totalPage); 9Gz=lc[!7
boolean hasPrePage = hasPrePage(currentPage); =?`c=z3~i$
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returnnew Page(hasPrePage, hasNextPage, i{qgn%#}Y
everyPage, totalPage, 9o!Bzy+_
currentPage, ^dxTm1Z
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beginIndex); wUM0M?_p[
} ,"0:3+(8;
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privatestaticint getEveryPage(int everyPage){ _Bj":rzY
return everyPage == 0 ? 10 : everyPage; wI "U7vr
} ??/
'kmd
L{Vqh0QD&
privatestaticint getCurrentPage(int currentPage){ -35;j'a
return currentPage == 0 ? 1 : currentPage; SZCze"`[
} K"@M,8hb
Uoix
privatestaticint getBeginIndex(int everyPage, int BfiD9ka-z
~7Ux@Sx;
currentPage){ yEQs:v6L~
return(currentPage - 1) * everyPage; /2VJX@h
} FXU8[j0P_G
;]:@n;c\
privatestaticint getTotalPage(int everyPage, int caX<
n>
h!9ei6
totalRecords){ ygl0k \
int totalPage = 0; dUdT7ixo
_PR4`C*
if(totalRecords % everyPage == 0) )Xyn
q(
totalPage = totalRecords / everyPage; Yz)qcU
else J<lO=
+mg
totalPage = totalRecords / everyPage + 1 ; +8ZF"{y
q-d:TMkc
return totalPage; Y`wSv NU
} 8*a&Jl
`~q <N
privatestaticboolean hasPrePage(int currentPage){ r9G>jiw8
return currentPage == 1 ? false : true; ht}wEvv
} uFga~g
B4 }bVjs
privatestaticboolean hasNextPage(int currentPage, hehFEyx
R0-j5&^jju
int totalPage){ lU8Hd|@-
return currentPage == totalPage || totalPage == b5n'=doR/I
lsNd_7k
0 ? false : true; -d:Jta!}{
} kylVH!
@l
@pU)_d!pJ
%ULr8)R;
} Dv`c<+q(#
\xoP)Ub>
e\75:oQ
X)3!_
RViuJ;
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。 }*"p?L^p{
"g8M0[7e3
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 %H"47ZFxAs
L_iFt!
做法如下: 7. ;3e@s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y"wShAR
Pk)1WK7E
的信息,和一个结果集List: )w%!{hn
java代码: R*r#E{!V;
S|+o-[e8O
8}| (0mC
/*Created on 2005-6-13*/ r]36zX v
package com.adt.bo; jrh43
\$*
v/=}B(TDF
import java.util.List; JqiP>4Uwm^
jo@J}`\Zt
import org.flyware.util.page.Page; jW@Uo=I[
*-p}z@8
/** V3j= Kf
* @author Joa 8)I^ t81
*/ @f_+=}|dc
publicclass Result { [!OxZ!
|ZBI *
private Page page; 5`: Yye
#>+ HlT
private List content; Y:a]00&)#Y
f&
'
/** N] sAji*
* The default constructor HyWCMK6b
*/ ?6Y?a2 |
public Result(){ q'82qY
super(); HHsmLo c4
} U4B(#2'
wD)XjX
/** ~e@z;]CiY
* The constructor using fields TRq6NB
* "9e\c;a
* @param page L;I]OC^J
* @param content sLQ^F
*/ DR<9#RRD
public Result(Page page, List content){ H_Q+&9^/
this.page = page; 0"bcdG<}
this.content = content; ea')$gR
} 'b{]:Y
`W*U4?M
/** _5N]B|cO
* @return Returns the content. ixD)VcD-f
*/ CzEd8jeh7
publicList getContent(){ kPLxEwl
return content; W6/yn
} D>tR-
^DwYOo 2B
/** p.?rey<%
* @return Returns the page. LSr]S79N1
*/ ~R92cH>L
public Page getPage(){ ,\%c^,HLJ
return page; )I.$=s
} B0]~el
6,{$J
/** ZzT9j~
* @param content Y/zj[>
* The content to set. QMb Ouw
*/ (JFWna0@
public void setContent(List content){ t{vJM!kdlQ
this.content = content; 6V01F8&w
} YcpoL@ab
rh}J3S5vp
/** gSQJJxZ{?
* @param page j eP
* The page to set. g7W"
*/ |8tilOqI
publicvoid setPage(Page page){ `RL"AH:+
this.page = page; hx]?&zT@
} SNI)9k(T{
} *CI#+P
5]Y?m'
}S<2A7)el
kL"2=7m;
YteO6A;
2. 编写业务逻辑接口,并实现它(UserManager, 4@#
`t5H
HCC#j9UN6
UserManagerImpl) @r/nF5
java代码:
wcY?rE9
%M|hA#04vZ
}Ud*TOo `
/*Created on 2005-7-15*/ Dwfu.ZJa
package com.adt.service; YglmX"fLf
k_nql8H
import net.sf.hibernate.HibernateException; 9m~p0 ILh
<l E<f+
import org.flyware.util.page.Page; {[?(9u7R
1NA.nw.
import com.adt.bo.Result; q9r[$%G
ZRU{[4
/** i6Emhji
* @author Joa mSh[}%swj
*/ &Ys<@M7E:
publicinterface UserManager { .jjG(L
JYbL?N
public Result listUser(Page page)throws Vb]=B~ ^`
[%1CRk
HibernateException; mSl.mi(JiZ
K^<BW(s
} ok\vQs(a
Q:d]imw!O
0[?Xxk}s0
?QdWrE_
aQ\$A`?
java代码: :(*V?WI
K:#I
*d4eK+U$5
/*Created on 2005-7-15*/ \\B(r
package com.adt.service.impl; @>Km_Ax
VY=jc~c]v
import java.util.List; ^ Q ?
CU2*z(]&
import net.sf.hibernate.HibernateException; _H7x9
y=
#( 146
import org.flyware.util.page.Page; N)\. [v
import org.flyware.util.page.PageUtil; ra
g Xn
O`t&ldU
import com.adt.bo.Result; fdi\hg^x
import com.adt.dao.UserDAO; ,w:U#r~s"
import com.adt.exception.ObjectNotFoundException; eF-."1
import com.adt.service.UserManager; !9VY|&fHe
. ~~T\rmI
/** "CQa.%
* @author Joa =wV<hg)C
*/ ^EQ<SCh
publicclass UserManagerImpl implements UserManager { F8,RXlGfA[
,G?WAOy,
private UserDAO userDAO; h_,i&d@(
/dI&o,sA
/** (m(JK^
* @param userDAO The userDAO to set. T;a}#56{^
*/ ^7WN{0
publicvoid setUserDAO(UserDAO userDAO){ kxIF#/8
this.userDAO = userDAO; aP@N)"
} [uN?
~lp\%
,CcV/K
/* (non-Javadoc) >7T'OC
* @see com.adt.service.UserManager#listUser h_3E)jc
0#Y5_i|p
(org.flyware.util.page.Page) a:OQGhc=
*/ Ee%%d
public Result listUser(Page page)throws Q6!zZ))~
sfugY(m
HibernateException, ObjectNotFoundException { aa/(N7
int totalRecords = userDAO.getUserCount(); WUXx;9 >
if(totalRecords == 0) o&)8o5
throw new ObjectNotFoundException Z4w!p?Wqa
6@F9G4<Z
("userNotExist"); sW'AjI
page = PageUtil.createPage(page, totalRecords); 17"uf.G
List users = userDAO.getUserByPage(page); N gGp
returnnew Result(page, users); `w7v*h|P
} Ma']?Rb`
S3*`jF>q
} Hc$O{]sq
bP$dU,@p~
n&qg;TT
G3vxjD<DMW
oC: {aK6\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G+"t/?/
li'YDtMKCY
询,接下来编写UserDAO的代码: ;oKZ!ND
3. UserDAO 和 UserDAOImpl: 6"5A%{J
java代码: {
Vf XsI
r|fL&dtr
Ls$D$/:q?
/*Created on 2005-7-15*/ _~J
{wM
package com.adt.dao; "R1NG?;q
0oZ=
yh
import java.util.List; O1U= X:Zl
F Q7T'G![
import org.flyware.util.page.Page; u=?.}Pj
Q4!_>YZ
import net.sf.hibernate.HibernateException; =9boya,>
aFb==73aLw
/** .B]MpmpK
* @author Joa bz2ztH9 n
*/ i$:*Pb3mV
publicinterface UserDAO extends BaseDAO { v6M6>&RR|
Vl/+;6_
publicList getUserByName(String name)throws FaQe_;
L~rBAIdD
HibernateException; vrhT<+q
+_?hK{Ib"
publicint getUserCount()throws HibernateException; 8:c-k|CX
]}-7_n#cC
publicList getUserByPage(Page page)throws rq/yD,I,
r6MMCJ|G
HibernateException; ;4^Rx
kHghPn?8]
} 2G67NC?+
RXpw!
rb2S7k0{
Jr
,;>
'EEJU/"u
java代码: ug!s7fo^
J6s`'gFns
qo90t{|c
/*Created on 2005-7-15*/ Ustv{:7v
package com.adt.dao.impl; <ro7vPKNa
uk<4+x,2)
import java.util.List; 8 S:w7Hr
[#<-ZC#T*
import org.flyware.util.page.Page; |+FubYf?$
_"Dv
uR
import net.sf.hibernate.HibernateException; iZ3IdiZ
import net.sf.hibernate.Query; hYT0l$Ng
eueH)Xkf
import com.adt.dao.UserDAO; \=?a/
hLd^ agX
/** g2LM_1\
* @author Joa dUeN*Nq&(,
*/ Ja7R2-0ii#
public class UserDAOImpl extends BaseDAOHibernateImpl
{7"Q\
p*R;hU
implements UserDAO { |C;=-|
ld|5TN1
/* (non-Javadoc) 1b `1{%
* @see com.adt.dao.UserDAO#getUserByName IXMop7~
gq4Tb
c
oA
(java.lang.String) 4C6YO
*/ =t#llgi~
publicList getUserByName(String name)throws 1y4|{7bb
7Utn\l
HibernateException { 5Md=-,'J!
String querySentence = "FROM user in class GfxZ'VIn
*)$Uvw E
com.adt.po.User WHERE user.name=:name"; AP n| \
Query query = getSession().createQuery p,5i)nEFj
|sJ[0z
(querySentence); ,8S/t+H
query.setParameter("name", name); oA7tEu
return query.list(); Dzpq_F!;V
} #`qx<y*S
4M=]wR;
/* (non-Javadoc) 7X`g,b!
* @see com.adt.dao.UserDAO#getUserCount() IA fcT!{
*/ FZ{h?#2?
publicint getUserCount()throws HibernateException { [SjqOTon{
int count = 0; jnkR}wAA
String querySentence = "SELECT count(*) FROM !hA-_
6+#Ydii9E
user in class com.adt.po.User"; MD}w Y><C
Query query = getSession().createQuery 2prU
-V*R\,>
(querySentence); GL>O4S<`
count = ((Integer)query.iterate().next DzAg"6=CS
yJ[0WY8<kC
()).intValue(); QGMV}y
return count; JinUV6cr
} \0^Kram>
70yFaW
/* (non-Javadoc) fF!Yp iI"
* @see com.adt.dao.UserDAO#getUserByPage h/QXPdV
!4ocZmj\
(org.flyware.util.page.Page) wm+};L&_
*/ q\9JgD)
publicList getUserByPage(Page page)throws F#3Q_G^/
j"8ZM{aO
HibernateException { SpIv#?
String querySentence = "FROM user in class f%A;`4`q
lne|5{h
com.adt.po.User"; ")1:F>
Query query = getSession().createQuery WJ]T\DI
u%GEqruo[
(querySentence); pN,u`[
query.setFirstResult(page.getBeginIndex()) G~]Uk*M
q
.setMaxResults(page.getEveryPage()); :;v~%e{k
return query.list(); +i6GHBn~J
} .o6Or:L
4V"E8rUL(
} :^<3>zk
"-E\[@/
;_XFo&@
;gD})@
OMky$d#
至此,一个完整的分页程序完成。前台的只需要调用 lPe&h]@ >
Q*GN`07@?d
userManager.listUser(page)即可得到一个Page对象和结果集对象 x
o;QCOH
b;L\EB
的综合体,而传入的参数page对象则可以由前台传入,如果用 k<z)WNBf
5G}?fSQ>
webwork,甚至可以直接在配置文件中指定。 }czrj%6
X hR4ru`
下面给出一个webwork调用示例: &L3M]
java代码: BqEI(c6
T%+#xl
V( }:=eK
/*Created on 2005-6-17*/ }YQX~="
package com.adt.action.user; }ZYd4h|g\z
)',R[|<
import java.util.List; YH$-g
"%)qRe
import org.apache.commons.logging.Log; 1pVS&0W
import org.apache.commons.logging.LogFactory; *9
{PEx
import org.flyware.util.page.Page; gE-tjoJ
bt SRtf
import com.adt.bo.Result; KA5v +~
import com.adt.service.UserService; 39c2pV[
import com.opensymphony.xwork.Action; 8H[<X_/ke
50h!
X9
/** `6;?9NI
* @author Joa e
v}S+!|U
*/ + SzU
publicclass ListUser implementsAction{ 3qgS&js 7
uuEV_ "X
privatestaticfinal Log logger = LogFactory.getLog A.F%Ycq
a9e>iU
(ListUser.class); {'flJ5]
je\Ph5 "
private UserService userService; 85= )lu
rCEyQ)R_}
private Page page; !"AvY y9
m~BAyk^jo3
privateList users; TJd)K$O>
.D~;u-%|F
/* fy1|$d{'
* (non-Javadoc) Mc
lkEfn
* ]2A^1Del
* @see com.opensymphony.xwork.Action#execute() ;7*[Bcj.
*/ >fG3K`
publicString execute()throwsException{ 6{K,c@VFd
Result result = userService.listUser(page); 2YL?,uLS
page = result.getPage(); U)TUOwF
users = result.getContent(); 299H$$WS,Z
return SUCCESS; g@Z))M+
} b1q"!+8y
j8i[ONq^
/** >IafUy
* @return Returns the page. te`$%NRl
*/ |T /ZL!
public Page getPage(){ sFKX-S~:
return page; (y'hyJo
} Y;eZ9|Ht9
a~`eQ_ND
/** R+:yVi[F]U
* @return Returns the users. _%Bi: HG0
*/ =[ 46`-_
publicList getUsers(){ z|uDy2
return users; .#!lP/.eQP
} Y|m+dT6
j3oV+zZ49
/** \&:nFb%=
* @param page l9~e".
~'
* The page to set. h8j.(
*/ B4/>H|
publicvoid setPage(Page page){ $p8xEcQdU#
this.page = page; T~?Ff|qFC
} ' {OgN}'{
>{]%F*p4
/** LrfVh-}|:Y
* @param users <{p4V|:
* The users to set. 4KAZ ':
*/ ;}WeTA_-[
publicvoid setUsers(List users){ mUC)gA/
this.users = users; PQt")[
} Mt|zyXyzX
SGRp3,1\4%
/** Jrf=@m\dk
* @param userService KkyVSoD\
* The userService to set. }Bh8=F3O
Q
*/ :VBV&l`
[
publicvoid setUserService(UserService userService){ w/<L
Ag
this.userService = userService; s+Pq&<nV-
} "^[ 'y7i
} bP#:Oi0v`
9=M$AB
;+_:,_
YqD=>P[O
^e5=hH-%
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, +/7?HGf
u#fM_>ML
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 /62!cp/F/D
,KZ~?3$yj
么只需要: !n!*/[}X
java代码: 8nqG<!,q
s[*rzoA
#zy:a%
<?xml version="1.0"?> Es`Px_k
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork DK~xrU'
~Cttzn]pR
1.0//EN" "http://www.opensymphony.com/xwork/xwork- @;4zrzQi7
G>=*yqo
1.0.dtd"> octL"t8w
2s8a
$3
<xwork> bj^5yX;2
?81c 4w
<package name="user" extends="webwork- @{e}4s?7od
]q[D>6_
interceptors"> l'1pw
~/U1xk%
<!-- The default interceptor stack name [aLI
'
@bLy,Xr&
--> B@))8.h]
<default-interceptor-ref 2.y-48Nz
I{&[[7H
name="myDefaultWebStack"/> 59L\|OR
v~C
Czg
<action name="listUser" :4w ?#
U>SShpmZA
class="com.adt.action.user.ListUser"> Vt~{Gu-Y
<param Pm?KI<TH~
(E3b\lST
name="page.everyPage">10</param> `[yKFa
I
<result #z%fx
est9M*Fn
name="success">/user/user_list.jsp</result> Kw^ 7>\
</action> aO[w/cGQ
# w4-aJ
</package> Lb-OsKU
>|=ts
</xwork> H41?/U,{
ty!`T+3
Qel9G($=
E&w7GZNt
I
34>X`[o
a-tmq]]E
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 @1j
QIEJ6`
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。 #X$\&,Yn"
W@IQ^
}E
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,qwuLBW
ue"~9JK.
ATyEf5Id_
lVa%$F{Pq
j;r-NCBnz
我写的一个用于分页的类,用了泛型了,hoho {Xy5pfW
Q
4_lrg|X1
java代码: 1I6px$^E\
r;2^#6/Z
.Hm>i
package com.intokr.util; >:!5*E5?
_f,C[C[e&
import java.util.List; ({_{\9O,3
c6]U E@A
/** s8Q 5ui]
* 用于分页的类<br> :-Z2:/P
* 可以用于传递查询的结果也可以用于传送查询的参数<br> qR{=pR
* cjY-y-vO
* @version 0.01 OT*mO&Z
* @author cheng kTB0b*V
*/ >U>(`r*
public class Paginator<E> { gD?l-RT>
privateint count = 0; // 总记录数 uW{l(}0N
privateint p = 1; // 页编号 .<FH>NW)
privateint num = 20; // 每页的记录数 sP~<*U.7
privateList<E> results = null; // 结果 j$:~Rek
00y!K
m_D
/** w9imKVry
* 结果总数 *^4"5X@
*/ 33q}CzK
publicint getCount(){ ^
@5QP$.
return count; V!=,0zy~Z
} q;CiV
A)!*]o>U
publicvoid setCount(int count){ x,-75
this.count = count; ioCsV
} / SB;Von
jr."I+
/** 3$R1ipb
* 本结果所在的页码,从1开始 +'a^f5
* !pW0qX\1n
* @return Returns the pageNo. T^KKy0ZGM
*/ }0z)5c
publicint getP(){ SH$PwJ U
return p; ~mxO7cy5Cg
} 7}>E J
ki!0^t:9
/** t*u:hex
* if(p<=0) p=1 WT=;: j
* ~!L}yw
* @param p 4VSU8tK|N]
*/ Sm|6 %3
publicvoid setP(int p){ AkV#J,
3LC
if(p <= 0) eMsd37J
p = 1; u#.2w)!D
this.p = p; 9A=,E&
} 4HlQ&2O%#
IJ"q~r$
/** D@.6>:;il
* 每页记录数量 0e4{{zQx
*/ }Y\%RA
publicint getNum(){ 0h_|t-9j
return num; T8g$uFo
} /x$ nje,.
;_(4Q*Yx
/** Q2gq}c~
* if(num<1) num=1 TeM|:o
*/ QWYJ*
publicvoid setNum(int num){ lo+A%\1
if(num < 1) Xv^qVn4
num = 1; i/4>2y9/F4
this.num = num; tD)J*]G
} ga +dt
y)@wjH{6
/** K0>zxqY
* 获得总页数 yN-9[P8C
*/ N6:`/f+A>T
publicint getPageNum(){ f:}
x7_Q
return(count - 1) / num + 1; sgFEK[w.y
} k,*XG$2h
*2l7f`K
/** !Vk^TFt`
* 获得本页的开始编号,为 (p-1)*num+1 KWHY4
*/ 7[)E>XRE
publicint getStart(){ 4WB0Pt{
return(p - 1) * num + 1; fJg+ Ryo
} U K!(G
n[rCQdM&U"
/** $UwCMPs X
* @return Returns the results. ]f_p8?j"
*/ 2^7`mES
publicList<E> getResults(){ AK4t\D)K1
return results; guR/\z$D@C
} TLH1>pY&
?J0y|
public void setResults(List<E> results){ Bzf^ivT3L
this.results = results; I?CZQ+}Hq
} i
ct])
H5|;{q:j
public String toString(){ Pm7}"D'/
StringBuilder buff = new StringBuilder tw@X>
G1z
@0''k
(); jP.dDYc
buff.append("{"); {JLtE{
buff.append("count:").append(count); '&b+R`g'
buff.append(",p:").append(p); jH:[2N?
buff.append(",nump:").append(num); :A;RH
buff.append(",results:").append F+qm[Bc8
%cn<ych
G
(results); UEL_uij
buff.append("}"); 307I$*%W
return buff.toString(); n$R)>nY
} }@)[5N#A|
Q>z8IlJ}
} .xkM.g4{~
i|kRK7[6B
?Bmb' 3