Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qPdNI1 |
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $NP5Z0v7
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 za7h.yK }
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 hd1H
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分页支持类: ~uRG~,{rH
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java代码: o[*</A
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package com.javaeye.common.util; =tl[?6
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import java.util.List; ((rk)Q+;v
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publicclass PaginationSupport { +v%V1lf^~
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publicfinalstaticint PAGESIZE = 30; MJ[#Gq\0R
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privateint pageSize = PAGESIZE; b3e:F{n
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privateList items; k;:v~7VF
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privateint totalCount; UwY <3ul
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privateint[] indexes = newint[0]; +uW$/_Y$
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privateint startIndex = 0; QOIi/flK
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public PaginationSupport(List items, int o9M[Zr1@k
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totalCount){ *!UY;InanX
setPageSize(PAGESIZE); >x)YdgJ*
setTotalCount(totalCount); WM BntB
setItems(items); <Fb3\T L
setStartIndex(0); hNUAwTH6
} ^[XxE Lx
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public PaginationSupport(List items, int HTI1eLZ2
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totalCount, int startIndex){ 1&c>v3 $2
setPageSize(PAGESIZE); 8Q^yh6z
setTotalCount(totalCount); }[Uh4k8P
setItems(items); =nOV!!
setStartIndex(startIndex); S{j|("W"[
} a>`\^>G4
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public PaginationSupport(List items, int "|`8mNC
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totalCount, int pageSize, int startIndex){ +Tc4+q!
setPageSize(pageSize); "5e~19
setTotalCount(totalCount); Z$0r+phQk=
setItems(items); ?*E Y~'I
setStartIndex(startIndex); *=dFTd"#
} vJ>A
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publicList getItems(){ !zL1XW)q
return items; ^4]#Ri=U
} *x[B g]/
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publicvoid setItems(List items){ ([UuO}m-
this.items = items; tx&>Eo
} Jl&bWp^3
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publicint getPageSize(){ aGNVqS%y
return pageSize; ( gO ?-0
} tC\x9&:
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publicvoid setPageSize(int pageSize){ 8-cG[/|0
this.pageSize = pageSize; sl|s#+Z
} _3tHzDSG#
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publicint getTotalCount(){ &/=>:ay+#
return totalCount; BHn`e~
} >5wA B
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publicvoid setTotalCount(int totalCount){ R B.j@*
if(totalCount > 0){ u#%Ig3
this.totalCount = totalCount; |8&AsQd
int count = totalCount / 5. :To2
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pageSize; fOJk+?
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if(totalCount % pageSize > 0) Rp A76ug
count++; 93x.b]]"
indexes = newint[count]; >OE.6)'Rm
for(int i = 0; i < count; i++){ u_@%}zo?5*
indexes = pageSize * w>; :mf
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i; n<8$_?-
} mLk@&WxG
}else{ M
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this.totalCount = 0; Y_>z"T
} BzF.KCScs
} J[YA1
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publicint[] getIndexes(){ riZFcVsB
return indexes; G6JyAC9j
} VbM5]UT/
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publicvoid setIndexes(int[] indexes){ g}Hk4+
this.indexes = indexes; tzi+A;>c(v
} WRh&4[G'
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publicint getStartIndex(){ #"ayq,GC<
return startIndex; |/arxb&
} aen(Mcd3bg
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publicvoid setStartIndex(int startIndex){ 2P$l XGjh
if(totalCount <= 0) Cd'P
this.startIndex = 0; ce2d)FG}e
elseif(startIndex >= totalCount) FO_nS
this.startIndex = indexes )oTEB#J
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[indexes.length - 1]; FvG9PPd
elseif(startIndex < 0) "x9xJ
this.startIndex = 0; z:u`W#Rf
else{ B_hob
this.startIndex = indexes (m)%5*:
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[startIndex / pageSize]; @[=*w`1
} z(.$>O&6H
} L)8 +/+
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publicint getNextIndex(){ huvg'Yt
int nextIndex = getStartIndex() + -/x +M-X#
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pageSize; H!F'I)1
if(nextIndex >= totalCount) )FWF T:P~
return getStartIndex(); dadOjl)S)
else oge^2
return nextIndex; vlyq2>TfR
} 8o -?Y.2
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publicint getPreviousIndex(){ :m#vvH
int previousIndex = getStartIndex() - MFW?m,It)
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pageSize; enG6T
if(previousIndex < 0) YL){o$-N"J
return0; G8u8&|
else N#7 ]xL
return previousIndex; 3
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} [ R~+p#l+Q
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} ,;/4E
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抽象业务类 )V@qH]
java代码: }S#.Pw%
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/** 3BY/&'oX
* Created on 2005-7-12 w-B\AK?}
*/ Lj~lfO
package com.javaeye.common.business; .&sguAyG
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import java.io.Serializable; *uEU9fX
import java.util.List; S
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import org.hibernate.Criteria; ^iV@NVP
import org.hibernate.HibernateException; z7<^aS
import org.hibernate.Session; jb7=1OPD_
import org.hibernate.criterion.DetachedCriteria; 'Fonn
import org.hibernate.criterion.Projections; %i.|bIhmm
import ++dV5
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org.springframework.orm.hibernate3.HibernateCallback; uFok'3!g7%
import HhqqJEp0
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org.springframework.orm.hibernate3.support.HibernateDaoS dtF6IdAf
@%#(Hse
upport; kk~{2
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import com.javaeye.common.util.PaginationSupport; dtg Ja_
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public abstract class AbstractManager extends SN]/~>/
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HibernateDaoSupport { :+R5"my
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privateboolean cacheQueries = false; wSAm[.1i
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privateString queryCacheRegion; ADR`j;2
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publicvoid setCacheQueries(boolean =pk'a_P8-
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cacheQueries){ kBONP^xI
this.cacheQueries = cacheQueries; ko5\*!|:lj
} 8p5'}Lq
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publicvoid setQueryCacheRegion(String D>|:f-Z6Z
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queryCacheRegion){ >^ Y9p~
this.queryCacheRegion = PN'8"8`{
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queryCacheRegion; "q(&<+D@
} ;m5M:Z"
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publicvoid save(finalObject entity){ O Z#?
getHibernateTemplate().save(entity); `3+U6>U [
} ^M80 F 7
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publicvoid persist(finalObject entity){ ^#=L?e
getHibernateTemplate().save(entity); H!Od.$ZIX
} 8odVdivh
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publicvoid update(finalObject entity){ @i`gR%
getHibernateTemplate().update(entity); w+MdQ@'5
} }`MO}Pz
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publicvoid delete(finalObject entity){ Qb|dp~K.M
getHibernateTemplate().delete(entity); Kz<xu ulr
} 0)/214^&
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publicObject load(finalClass entity, c8'8DM
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finalSerializable id){ g@U#Y#b@"
return getHibernateTemplate().load o}%fs
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(entity, id); AzV5Re8M
} wH`@r?&
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publicObject get(finalClass entity, e7qT;
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finalSerializable id){ 3Yf$WE8#l
return getHibernateTemplate().get gON6jnDO
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(entity, id); |`okIqp
} 4ku /3/6
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publicList findAll(finalClass entity){ =aekY;/
return getHibernateTemplate().find("from [_0g^(`
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" + entity.getName()); i f"v4PHq
} N0piL6Js
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publicList findByNamedQuery(finalString - VE#:&
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namedQuery){ ku{aOV%
return getHibernateTemplate <- ?B#
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().findByNamedQuery(namedQuery); 4sAshrUf
} |")x1'M
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publicList findByNamedQuery(finalString query, \1Bgs^
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finalObject parameter){ nx4aGS"F:
return getHibernateTemplate n>4S P_[E7
S?{5DxilO
().findByNamedQuery(query, parameter); ep?0@5D}]
} xHGoCFB
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publicList findByNamedQuery(finalString query, VZ,T`8"
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finalObject[] parameters){ 9,W-KM
return getHibernateTemplate .$k"+E
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().findByNamedQuery(query, parameters); !lF^~x
} :qbG%_PJ
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publicList find(finalString query){ }"-r;i
return getHibernateTemplate().find | rvr Sab)
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(query); jQb D2x6(
} 9PJDT]
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publicList find(finalString query, finalObject Kzb@JBIF
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parameter){ @5wg' mM
return getHibernateTemplate().find E8i:ER $$7
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(query, parameter); <C77_t
} Q7r,5w&cm
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public PaginationSupport findPageByCriteria gp HwiFc
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(final DetachedCriteria detachedCriteria){ Dkb&/k:)
return findPageByCriteria bw\=F_>L
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); zl\#n:|
} d]3sC
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public PaginationSupport findPageByCriteria !d\GD8|4
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(final DetachedCriteria detachedCriteria, finalint m3!M L>nLt
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startIndex){ { 9 ".o,
return findPageByCriteria F29AjW86
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(detachedCriteria, PaginationSupport.PAGESIZE, _zh5KP[{
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startIndex); ]e.+u
} md"%S-a_dT
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public PaginationSupport findPageByCriteria kDq%Y[6Z
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(final DetachedCriteria detachedCriteria, finalint ?vFh)U
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pageSize, !h!9SE
finalint startIndex){ ^ kvH/ Y&
return(PaginationSupport) MjB[5:s
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getHibernateTemplate().execute(new HibernateCallback(){ Td*Oljj._U
publicObject doInHibernate XL^N5
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(Session session)throws HibernateException { A=UIN!
Criteria criteria = Fz&ilB
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detachedCriteria.getExecutableCriteria(session); suFOc
int totalCount = #@^w>D6W
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((Integer) criteria.setProjection(Projections.rowCount lM^!^6=v0l
A.9'pi'[9Q
()).uniqueResult()).intValue(); =jc8=h[F<
criteria.setProjection V1)P=?%(US
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(null); \!Zh= "hN
List items = a~F@3Pd
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criteria.setFirstResult(startIndex).setMaxResults V2{#<d-T!
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(pageSize).list(); &hN&nH"PC
PaginationSupport ps = Tki/d\!+
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new PaginationSupport(items, totalCount, pageSize, e[mhbFf-
,'CWt]OS'
startIndex); 7&V^BW
return ps; |.O!zRm
} h5rP]dbhXU
}, true); R.IUBw5;/
} J xm9@,
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public List findAllByCriteria(final FJ~_0E#L
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DetachedCriteria detachedCriteria){ MW$H/:3
return(List) getHibernateTemplate @:+n6
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().execute(new HibernateCallback(){ 6'Yn|A
publicObject doInHibernate b+].Uc
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(Session session)throws HibernateException { H!r
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Criteria criteria = }<ONx g6Kb
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detachedCriteria.getExecutableCriteria(session); w2N3+Tkg
return criteria.list(); >xV<nLf/
} &rztC]jF
}, true); R P:F<`DB|
} ]Wd`GI
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public int getCountByCriteria(final $dTfvd
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DetachedCriteria detachedCriteria){ o1X/<.0+
Integer count = (Integer) GGc_9?h
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getHibernateTemplate().execute(new HibernateCallback(){ ?e y&Un"
publicObject doInHibernate MAe<.DHY
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(Session session)throws HibernateException { x)VIA]
Criteria criteria = ;5Vk01R
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detachedCriteria.getExecutableCriteria(session); f'6qJk%J
return Uk*;C
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criteria.setProjection(Projections.rowCount TdP{{&'9
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()).uniqueResult(); rw8J:?0x
} nN=:#4
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}, true); pO/SV6N
return count.intValue(); vbA7I<;
} A2|o=mOH
} ))IgB).3M
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用户在web层构造查询条件detachedCriteria,和可选的 L_U3*#Zdz7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 X4} `>
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PaginationSupport的实例ps。 /%uZKGP
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ps.getItems()得到已分页好的结果集 /;<e.
ps.getIndexes()得到分页索引的数组 _7=pw5[
ps.getTotalCount()得到总结果数 pcuMGo-#
ps.getStartIndex()当前分页索引 yF/< :
ps.getNextIndex()下一页索引 -.b
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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 6)#- 5m
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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 ayH%
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一下代码重构了。 ^A11h6I
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我把原本我的做法也提供出来供大家讨论吧: `rz`3:ZH
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首先,为了实现分页查询,我封装了一个Page类: xH"W}-#[
java代码: ?GUz?'d
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/*Created on 2005-4-14*/ mEB2RLCM
package org.flyware.util.page; |5O >>a()
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/** lPRdwg-
* @author Joa h;EwkbDQg>
* nE]~E xr
*/ x2j/8]'o
publicclass Page { 28T\@zi
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/** imply if the page has previous page */ Jt-XmGULB
privateboolean hasPrePage; [GR]!\!%~
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/** imply if the page has next page */ <\1}@?NGC
privateboolean hasNextPage; 9C557$nS^
9n>$}UI\
/** the number of every page */ ]RH=s7L
privateint everyPage; ><;l:RGK|
GOYn\N;V2
/** the total page number */ )Lc<;=w'9
privateint totalPage; 85r)>aCMn
1u"R=D9p,=
/** the number of current page */ c&7Do}
privateint currentPage; %rpR-}j
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/** the begin index of the records by the current ?%\mQmjas
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query */ '2|1%NSW9
privateint beginIndex; /h?<MI\7V
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/** The default constructor */ WF ?/GN
public Page(){ T!u'V'Ei2
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} @9OeC
O
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/** construct the page by everyPage [;(]Jy
* @param everyPage CS~=Z>6EjA
* */ *.kj]BoO
public Page(int everyPage){ Cz'xGW{
this.everyPage = everyPage; ]j& FbP)3
} +M44XhT
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/** The whole constructor */ o"'iXUJ
public Page(boolean hasPrePage, boolean hasNextPage, %B#hb<7}
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int everyPage, int totalPage, d^KBIz8$5l
int currentPage, int beginIndex){ ^G}# jg.
this.hasPrePage = hasPrePage; >Hdjsu5{N
this.hasNextPage = hasNextPage; vP3K7En
this.everyPage = everyPage; GN\8![J
this.totalPage = totalPage; wl7 M fyU
this.currentPage = currentPage; !2GHJHxv]c
this.beginIndex = beginIndex; xK$}QZ)
} /a@ k S
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/** +VSZhg,Np8
* @return wENzlXeOP
* Returns the beginIndex. \Os:6U=X-
*/ s{yJ:WncI
publicint getBeginIndex(){ 0-*Z<cu%l
return beginIndex; NNwc!x)*
} (N,nux(0k
)r ULT$;i@
/** $GQphXb$
* @param beginIndex .W!tveX8-
* The beginIndex to set. E;9Z\?P
*/ 8ou e-:/a
publicvoid setBeginIndex(int beginIndex){ tY{;
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this.beginIndex = beginIndex; ,/~[S
} )yHJ[
@(Z( /P;:
/** M[A-1]'
* @return D~Z=0yD
* Returns the currentPage. Af`z/:0<
*/ BRe{1i 6
publicint getCurrentPage(){ 3f_i1|>)'
return currentPage; ]x1p!TSU
} Was'A+GZ
TW>?h=.z
/** [1NaH
* @param currentPage !~kEtC
* The currentPage to set. ~NxEc8Y
*/ ,NDh@VYe
publicvoid setCurrentPage(int currentPage){ USprsaj
this.currentPage = currentPage; sN-oEqS
} 5)mVy?Z
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/** Te+^J8
* @return K${}r0
* Returns the everyPage. [G\o+D?2
*/ `Z:3`7c
publicint getEveryPage(){ q?yMa9ZZky
return everyPage; IK3qE!,&U
} YX_vv!-]
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/** |ixGY^3;
* @param everyPage B3Mx,uXT\
* The everyPage to set. bjlkX[{}I
*/ $:e)$Xnn-
publicvoid setEveryPage(int everyPage){ $Buf#8)F*
this.everyPage = everyPage; AQe!Sqg'
} K}Na3}m
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/** v{.\iIg N
* @return W<Z$YWr
* Returns the hasNextPage. QNb>rLj52
*/ P% Q@9kO>
publicboolean getHasNextPage(){ "c,!vc4
return hasNextPage; *="m3:c'J
} 9\>sDSCx
=5Wp&SM6
/** |YRY!V_w
* @param hasNextPage 2A>C+Y[7\
* The hasNextPage to set. y^G>{?Tha
*/ 3%2jwR
publicvoid setHasNextPage(boolean hasNextPage){ PPj[;(A
this.hasNextPage = hasNextPage; xZyeX34{M;
} /$Z
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/** 2 h<U
* @return y@`~ 9$
* Returns the hasPrePage. b_l3+'#ofM
*/ ESIzGaM
publicboolean getHasPrePage(){ U{}!y3[wK
return hasPrePage; Af9+HI
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} "J!}3)n
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/** ]\BUoQ7I/
* @param hasPrePage a.DX%C/5
* The hasPrePage to set. [sj VRW-
*/ t:=k)B
publicvoid setHasPrePage(boolean hasPrePage){ H_Os4}
this.hasPrePage = hasPrePage; %[ /<+
} #k9<
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/** 7 2,"Cj
* @return Returns the totalPage. Qci$YTwl>
* g4wZvra6%)
*/ 30_ckMG"g
publicint getTotalPage(){ !| xZ6KV
return totalPage; g~!$i`_b
} Us-A+)r*!
8;#AO8+U7)
/** nJT4w|Yx
* @param totalPage :Q-oV8t{
* The totalPage to set. Q0~j$Jc
*/ ^PqMi:htc
publicvoid setTotalPage(int totalPage){ #6W,6(#^#
this.totalPage = totalPage; Jq
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} J?%}=_fsa
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} 1,`H:%z%
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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 eN/G i<
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个PageUtil,负责对Page对象进行构造: T'1gy}
java代码: GaBTj_3
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/*Created on 2005-4-14*/ A#DR9Eq
package org.flyware.util.page; KDey(DN:
+\`rmI
import org.apache.commons.logging.Log; <I2z&
import org.apache.commons.logging.LogFactory; .Yx_:h=u
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/** mqFq_UX/T
* @author Joa ;&f1vi4
* % fhNxR
*/ !/hsJ9
publicclass PageUtil { SDBt @=Nl
B QjGv?p0s
privatestaticfinal Log logger = LogFactory.getLog n?E}b$6
c Zvf"cIs
(PageUtil.class); $|a;~m>
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/** ctI{^f:
* Use the origin page to create a new page u Z(? >
* @param page u~F~cDu
* @param totalRecords Eg8i _s~:
* @return YG[w@u
*/ MzTW8
publicstatic Page createPage(Page page, int ;>ozEh#8w
s".HEP~]=
totalRecords){ 5=Lq=,K$
return createPage(page.getEveryPage(), 8&E}n(XE
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page.getCurrentPage(), totalRecords); js <Ww$zFW
} z~Na-N
N:W9},
/** nvyB/
* the basic page utils not including exception ^M[P-#X_
$j*Qo/xd
handler Zdn!qyR`
* @param everyPage ai^|N.!
* @param currentPage ^o eJKjJ
* @param totalRecords 9_huI'"p
* @return page /Ox)|)l
*/ rK|*hcy
publicstatic Page createPage(int everyPage, int 'HaD~pa
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currentPage, int totalRecords){ (|u31[
everyPage = getEveryPage(everyPage); Kf.T\V4%
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, 3-x%wD.
{#hVD4$b
currentPage); `s/?b|,
int totalPage = getTotalPage(everyPage, fL6e?\Pw
U Cb02h
totalRecords); OhwF )p=
boolean hasNextPage = hasNextPage(currentPage, h-XY4gq/
Mv|!2 [:
totalPage); Y25uU%6t_
boolean hasPrePage = hasPrePage(currentPage); 6|=j+rScv
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returnnew Page(hasPrePage, hasNextPage, _\zQ"y|G
everyPage, totalPage, k-jahm4
currentPage, r"]'`qP,
>"d?(@PJ
beginIndex); m 7LUrU
} 4 I@p%g&
qL
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privatestaticint getEveryPage(int everyPage){ `;%Z N
return everyPage == 0 ? 10 : everyPage; {j
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} .6.^G
G0d&@okbFC
privatestaticint getCurrentPage(int currentPage){ f8n
V=AQ
return currentPage == 0 ? 1 : currentPage; 9-lEt l%
} PCE4W^ns
mP^SS
Je
privatestaticint getBeginIndex(int everyPage, int I:=dG[\h2
`
\ZqgX4
currentPage){ 0A[e sWmP
return(currentPage - 1) * everyPage; gv.6h{Ut
} 63&^BW
!:0v{ZQ
privatestaticint getTotalPage(int everyPage, int 7@;">`zvm
;L"!I3dM)
totalRecords){ ?M}S|dsmE
int totalPage = 0; X?Pl<l&
46x.i;b7
if(totalRecords % everyPage == 0) E^V|
totalPage = totalRecords / everyPage; ^k/i-%k0
else rT6?!$"%.
totalPage = totalRecords / everyPage + 1 ; ^vni&sJ
0^l%j 8/
return totalPage; ?J!3j{4e
} ocQWQ
R[Fn0fnLx
privatestaticboolean hasPrePage(int currentPage){ 1{PG>W
return currentPage == 1 ? false : true; vmZ"o9-{#X
} uO(w1Q"^
3Qn!y\#
privatestaticboolean hasNextPage(int currentPage, \
v2H^j/
Akk
3 Qx
int totalPage){ 93Yn`Av;
return currentPage == totalPage || totalPage == $P {K2"Oc
QwWW!8
0 ? false : true; AHbZQulC
} ;)hw%Z]Jj$
xBM>u,0.F
|D#2GeBw1h
} W<,F28jI3v
NC"yDWnO'
!!,0'c
Va<eusl
5>_5]t
{
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。 #/-_1H
2Aq~D@,9=:
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 EtJ8^[u2J
FY'dJY3O
做法如下: &X>7n~@0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 't (O$
Z|m`7xeCy
的信息,和一个结果集List: 5Jk<xWKj
java代码: ]7YNIS
wa09$4>_w
_^S]g mE
/*Created on 2005-6-13*/ C"pB"^0
package com.adt.bo; v! hY
zqySm)o]
import java.util.List; kI\tqNJ i
J./d!an
import org.flyware.util.page.Page; ~}9PuYaD@
Hh[Tw&J4
/** ]!"S+gT*C
* @author Joa =t0tK}Y+4
*/ 7(k^a)~PL
publicclass Result { sfD5!Z9#1
m@G i6
private Page page; <^R{U&Z@
D{7w!z
private List content; )0 Z! n
I*|P@0
/** Wr~yK? : ]
* The default constructor i775:j~zx0
*/ c-1q2y
public Result(){ DocbxB={I
super(); `#s#it'y
} MN8H;0g-
k[|~NLB8
/** 1}m3;
* The constructor using fields l&(l$@t
* ;/O#4]2*
* @param page rxZi8w>}
* @param content ~qVz)<
*/ Tbbz'b;{
public Result(Page page, List content){ U]6&b
this.page = page; P.\nLE J=
this.content = content; X JGB)3QI
} r`'y?Bra;
D)$8W[
/** <O~WB
* @return Returns the content. ^c}J,tZ]
*/
U^lW@u?:
publicList getContent(){ + =$
return content; "eAy^,
} @I3eK^#|P
b{M7w
/** T3%C%BcX
* @return Returns the page. .10y0FL4
*/ 3)Ac"nuyqH
public Page getPage(){ i&Fiq&V)[
return page; dR^"X3$
} (<*e
BHFY%6J!
/** Cr ?4Ngw
* @param content yzsab ^]
* The content to set. H1:be.^YP
*/ |`d0^(X
public void setContent(List content){ zy'D!db`Z
this.content = content; wE\3$ s/{D
} sq /]wzT:
0ZpFE&
/** CO+/.^s7}S
* @param page dP2irC%f8
* The page to set. TCKu,}s
*/ @Yw,nQE)b
publicvoid setPage(Page page){ `YBkF
this.page = page; Y4.Eq+$gh
} GwU?wIIj^
} 9O*_L:4o
8|?LN8rp
&^&zR(o`
+UN <Zp7I/
,3i,P(?(
2. 编写业务逻辑接口,并实现它(UserManager, Y.#:HRtgW
p,g1eb|E
UserManagerImpl) ^L4Qbc(vJ
java代码: a,t``'c;
bvBHYf:^
wN-i?Ek0;
/*Created on 2005-7-15*/ 1j-te-}"c
package com.adt.service; `lDut1J5n
%(/!ljh_
import net.sf.hibernate.HibernateException; VZn=rw
`6Qdfmk=
import org.flyware.util.page.Page; QnouBrhO
yF._*9Q3hK
import com.adt.bo.Result; FyoEQ%.bI
/t<@"BoV
/** m#/_x
* @author Joa Z;Rp+X
*/ G2{O9
publicinterface UserManager { SzDKByi
s)
O[t
public Result listUser(Page page)throws #EGA#SKoq
,B}I?vN.
HibernateException; t>)45<PEw
qSCv )S(
} BKa-
k!
&)F*@C-
RkeltE~u
b^c9po
smY$-v)@
java代码: CWo1.pV w
'|>9C^E9X
uQb!= ]
/*Created on 2005-7-15*/ tirIgZ
package com.adt.service.impl; -D^A:}$
)3<:tV8
import java.util.List; o_M.EZO
_Us*+
2(4L
import net.sf.hibernate.HibernateException; A=zPLq{Sb
)2q~u%9n
import org.flyware.util.page.Page; AdZ;j6#
import org.flyware.util.page.PageUtil; s pLZ2]A
|WryBzZ>on
import com.adt.bo.Result; -~" :f8
import com.adt.dao.UserDAO; nR>r2wMk@
import com.adt.exception.ObjectNotFoundException; RF!a//
import com.adt.service.UserManager; `i
+g{kE2M
ysIh[1E~%:
/** s^OO^%b
* @author Joa n(nBRCG)o
*/ Y<"7x#AB!
publicclass UserManagerImpl implements UserManager { cV{%^0?D
5v)(8|.M
private UserDAO userDAO; }ov&.,vQ
Dq@2-Cv
/** Z BUArIC
* @param userDAO The userDAO to set. {yU+)t(.
*/
>YtdA
publicvoid setUserDAO(UserDAO userDAO){ $2DuB
this.userDAO = userDAO; 8x{B~_~
} D<i[LZd
Fk;oE'"D
/* (non-Javadoc) {+<P:jbz;
* @see com.adt.service.UserManager#listUser mnk"Vr` L
{ x0 t
(org.flyware.util.page.Page) 6C4'BCYW(
*/ +|Hioq*,t
public Result listUser(Page page)throws U!%!m'
5Ky#GuC
HibernateException, ObjectNotFoundException { t2" (2
int totalRecords = userDAO.getUserCount(); !
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if(totalRecords == 0) l=N2lHU
throw new ObjectNotFoundException raVA?|'g~
D0(xNhmKz
("userNotExist"); FOwDp0
page = PageUtil.createPage(page, totalRecords); (R~]|?:wt
List users = userDAO.getUserByPage(page); f~OU*P>V@
returnnew Result(page, users); Xb
!MaNm)
} P #F=c34u
vzel#
} Y!q!5Crfi
-V"22sR]
K
]OK:hY4
Uawpfgc}
"N:XzG
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 l JP1XzN_
8 #X5K
询,接下来编写UserDAO的代码: \k`n[{
3. UserDAO 和 UserDAOImpl: (C]
SH\
java代码: l&VjUPz_
GsbAlNP
+QM@VQ
/*Created on 2005-7-15*/ zOEY6lAwI
package com.adt.dao; "TV(H+1,z
iGDLZE+?
import java.util.List; c H-@V<
]{
BEr*
import org.flyware.util.page.Page; 0,s$T2
bb42v7?
import net.sf.hibernate.HibernateException; b?4/#&z]
M}_i52
/** jJ4qR:]
* @author Joa g>d;|sK
*/ HBys
publicinterface UserDAO extends BaseDAO { ``,k5!a66\
3lLMu B+
publicList getUserByName(String name)throws cWGDee(
S|rgCh!h
HibernateException; Dlo xrdOY&
DcIvhB p
publicint getUserCount()throws HibernateException; B{oU,3U>
+(O~]Q-Ez
publicList getUserByPage(Page page)throws SYeadsvF
04%S+y.6&Y
HibernateException; &|%6|u9
]`g<w#
} 6+V\t+aug
N$Y " c*
P+t#4J
V>64/
]%uZ\Q;9p
java代码: :0K8h
E|YdcS
]Mj/&b>"e
/*Created on 2005-7-15*/ Sp}D;7
package com.adt.dao.impl; bi ozZ
]J9cVp
import java.util.List; 133I.XBU
B .TB\j
import org.flyware.util.page.Page; &bgvy'p
P^MOx4
import net.sf.hibernate.HibernateException; G5dO 3lwq
import net.sf.hibernate.Query; q(5j(G ;
e&MC|US=\
import com.adt.dao.UserDAO; (qn2xrV
;v17K
/** +6smsL~<#v
* @author Joa k"kJ_(
*/ d_S*#/k
public class UserDAOImpl extends BaseDAOHibernateImpl %8aC1x
nFX_+4V2
implements UserDAO { 4RKW
PUQES(&
/* (non-Javadoc) M,j(=hRJ/E
* @see com.adt.dao.UserDAO#getUserByName o }Tz"bN
E6Rz@"^XV
(java.lang.String) sfr(/mp(
*/ n/QF2&X7)
publicList getUserByName(String name)throws Ae^X35
p
<eC<dtu
HibernateException { @ZN^1?][
String querySentence = "FROM user in class eMOD;{Q?X
k~%<Ir1V]
com.adt.po.User WHERE user.name=:name"; 2=-utN@Z
Query query = getSession().createQuery m6eZ_&+u
q0%
(querySentence); wn
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query.setParameter("name", name); $(s\{(Wn
return query.list(); J" j.'.
} c8)/:xxl
|vte=)%
/* (non-Javadoc) %xwIt~Y
* @see com.adt.dao.UserDAO#getUserCount() )Fd
HV;K
*/ rQ4*k'lA:
publicint getUserCount()throws HibernateException { a/~aFmu6b
int count = 0; rzrl>9
h
String querySentence = "SELECT count(*) FROM E'1+ Yq
{)- .xG
user in class com.adt.po.User"; [w
-{r+[
Query query = getSession().createQuery ka\OJ7u
s57N) 0kP
(querySentence); sGY_{CZ:
count = ((Integer)query.iterate().next #6+FY+/
:H.
()).intValue(); NRnRMY-
return count; 0U66y6
} )PkNWj6%y
Xf=XBoN|
/* (non-Javadoc) H-rWDN#
* @see com.adt.dao.UserDAO#getUserByPage |6J ?8y
4@ILw
(org.flyware.util.page.Page)
|{g+Y
*/ STfyCtS
publicList getUserByPage(Page page)throws [~W`E1,
fsO9EEn7X
HibernateException { *IlaM'[*
String querySentence = "FROM user in class yTE%hHH]&[
aYL|@R5;e
com.adt.po.User"; KDi|(
Query query = getSession().createQuery |(
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[#" =yzR<3
(querySentence); ,O1O8TwUB0
query.setFirstResult(page.getBeginIndex()) QVZD/shq
.setMaxResults(page.getEveryPage()); d
"BW/%m|g
return query.list(); @Un/c:n
} r#WT`pav
va/m~k|i
} HLQ"?OFlz
w&Dv8Wv+Oq
?&WYjTU]H
C2]Kc{4
B;Nl~Y| \
至此,一个完整的分页程序完成。前台的只需要调用 ^Yr0@pE
TAL/a*7\
userManager.listUser(page)即可得到一个Page对象和结果集对象 vv6$>SU
[\)oo
的综合体,而传入的参数page对象则可以由前台传入,如果用 y<W8Q<9
kI*(V[i
webwork,甚至可以直接在配置文件中指定。 LCXO>MXN
ZZ/cq:3$ P
下面给出一个webwork调用示例: @#+jMV$g
java代码: p\wJD1s
lM\LN^f5*
zHB_{(o7
/*Created on 2005-6-17*/ f<i7@%
package com.adt.action.user; Rg29
F9c`({6k
import java.util.List; RnVtZ#SCh
O|kKwadC
import org.apache.commons.logging.Log; Ocg"M Gb
import org.apache.commons.logging.LogFactory; ^s7,_!.Pq
import org.flyware.util.page.Page; !2Dy_U=
|ifHSc.j<
import com.adt.bo.Result; sfp,Lq`
import com.adt.service.UserService; 9z
m|Lbj
import com.opensymphony.xwork.Action; m(D]qYwh
X{Yw+F,j
/** >QQ(m\a$
* @author Joa KYJ1}5n
*/ (lA.3 4.p
publicclass ListUser implementsAction{ VCNT4m
Mro4`GL
privatestaticfinal Log logger = LogFactory.getLog gLD`wfZR
v=YK8fNi
(ListUser.class); Pvo#pY^dXX
h>S[^
-,
private UserService userService; 7&}P{<}o^
iY[+Ywh
private Page page; U3;aLQ*
'iSAAwT2aj
privateList users; oR+-+-??$
}`/gX=91
/* A )nW
* (non-Javadoc) R U"/2i
* V|Tud
* @see com.opensymphony.xwork.Action#execute() !KS F3sz
*/ hPm>tV2X
publicString execute()throwsException{ 4FeEGySow
Result result = userService.listUser(page); x
FJg
page = result.getPage(); F
SMj
users = result.getContent(); KM?1/KZ/~
return SUCCESS; 9G?ldp8
}
V+MK'<#B
T~4mQuYi
/** yT /EHmJ
* @return Returns the page. L6:h.1 U$
*/ qX:B4,|ck
public Page getPage(){ ,1n
>U?5
return page; !jX4`/n2
} `qpc*enf0
MKGS`X]<J
/** H!r &aP
* @return Returns the users. tgFJZA
*/ /4S;QEv
publicList getUsers(){ rp!
LP#*
return users; O0~vf[i];
} 8Vl!|\x5
O>r-]0DI[
/** c|p,/L09L
* @param page Aw^yH+ae
* The page to set. Rz <OF^Iy
*/ +}7fg82)
publicvoid setPage(Page page){ n"{X!(RIcx
this.page = page; kka"C]!
} <zfe}0
R zR?&J
/** }F1s
tDx
* @param users PB'0?b}fab
* The users to set. J07O:cjyu
*/ <dR,'
publicvoid setUsers(List users){ uF(k[[qaiN
this.users = users; /9ZcM]X B
} B:oF;~d/,
I@7/jUO
/** r((Tavn
* @param userService _j#SpL'P
* The userService to set. wvc>0?t'
*/ '8Wv.X0`
publicvoid setUserService(UserService userService){ w8M2N]&:
this.userService = userService; SBKeb|H8
} rnhFqNT:
} Bt~s*{3$8
``4wX-y
+H'\3^C-
^[# &
^[-V
J%v5d*$.
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, GG-[`!>.pw
O&?.&h
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 =V $j6
M-9gD[m
么只需要: 6vz1*\:H~
java代码: Q|hm1q
-e>|kPfv!
Agy
<j
<?xml version="1.0"?> )^; DGzG
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork L@)&vn]
<)#kq1b?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- U{1z;lJ
us{nyil1
1.0.dtd"> hY8#b)l~lu
WR.x&m>
<xwork> bkQ3c-C<
mN1Ssq"B
<package name="user" extends="webwork- +uQB
rG
|HbEk[?^s
interceptors"> av' *u
Wc'Ehyi;
<!-- The default interceptor stack name 9;f|EGwZ
:EHQ .^
--> Ti= 3y497S
<default-interceptor-ref V/y=6wUiSl
9{eBgdC
name="myDefaultWebStack"/> cH"@d^"+q|
gbGTG(:1S
<action name="listUser" |O (G nsZ
xb^Mo.\[
class="com.adt.action.user.ListUser"> WcGXp$M
<param %?tq;~|]Q
Z;<ep@gy~
name="page.everyPage">10</param> U</+ .$b
<result &hN,xpC
(([I]q
name="success">/user/user_list.jsp</result> P^IY:
-s
</action> %g^"]
sbla`6Fb
</package> MW@ DXbKVl
XVUf,N,
</xwork> $L{7%]7QC
^
}#f()
j[DIz@^
a-PGW2G
h([0,:\
]h@{6N'oNS
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值
KOSyh<&
0|C[-ppr
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 YvTA+yL
-CU,z|g+
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 lgT?{,>RkW
Z{}+)Q*Q
dF,DiRD
i$O#%12l
XiG88Kwv
我写的一个用于分页的类,用了泛型了,hoho <xF?~7
`pYE[y+
java代码: N(R,8GF5G
3
jh|y,
wo(j}O-
package com.intokr.util; +89o`u_l%
N1?
iiv
import java.util.List; C4_t_N
bj.]o*u-
/** \{>eOD_
* 用于分页的类<br> f[@#7,2~M
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :&$Xe1)i]
* "jGe^+9uT
* @version 0.01 ? ).(fP
* @author cheng MZ^Ch
*/ E& ]_U$
public class Paginator<E> { ^
wQcB
privateint count = 0; // 总记录数 `Kp}s<
privateint p = 1; // 页编号 I"V3+2e
privateint num = 20; // 每页的记录数 GTFl}t
privateList<E> results = null; // 结果 UCF[oO>v
rqC1
/**
lt%-m@#/
* 结果总数 }}s)
+d
*/ &ps6s.K
publicint getCount(){ ro]L}oE+
return count; APuu_!ez1
} Ph\F'xROe
DZAH"sb
publicvoid setCount(int count){ \[E-:
this.count = count; v<fWc971
} q_58Lw
3mA/Nu_
/** Ib(,P3
* 本结果所在的页码,从1开始 -9Xw]I#QR
* p,^>*/O>
* @return Returns the pageNo. dh,7iQ
s
*/ |ZuDX87
publicint getP(){ \]GGVI;u
return p; "b;k.Fx
} Q2R>lzB
~p!QSRu~,b
/** 4+,*sn
* if(p<=0) p=1 <M>#qd@c
* %>]#vQ|
* @param p =z%s8D2
*/ m-#d8sD2C
publicvoid setP(int p){ Ko}7$2^
if(p <= 0) &@Yoj %%
p = 1; WFks|D:sB
this.p = p; 7x:F!0:
} w`38DF@K
a!{hC)d*
/** zN/Gy}
* 每页记录数量 Xa6qvg7/
*/ t9n'!
publicint getNum(){ <sF!]R&4
return num; lZ+/\s,]|
} _4S7wOq5
BC&^]M
/** ix+x3OCip
* if(num<1) num=1 33S`aJ
*/ @) ]t8(
publicvoid setNum(int num){ ~l@%=/m
if(num < 1) {.%0@{Y
num = 1; /iTH0@Kw;
this.num = num; N}1-2
} .y(@Y6hO
^W{eO@
/** Is~yVB02
* 获得总页数 f(W,m
>.;
*/ F.&*D~f
publicint getPageNum(){ ; vhnA$'a
return(count - 1) / num + 1; ob)D{4B'
} 7{8)ykBU^
T&e%/
/** DOA[iT";4
* 获得本页的开始编号,为 (p-1)*num+1 !DCVoc]pV
*/ LE Jlo%M
publicint getStart(){ /Ir 7
DZK
return(p - 1) * num + 1; 7YSuB9{M
} ]lC4+{V
<4S F~i
/** ~n)]dFy
* @return Returns the results. zh?xIpY
*/ o<Ke3?J\
publicList<E> getResults(){ 8~rT
return results; .jy)>"h0
} P/HHWiD`D
],WwqD=
public void setResults(List<E> results){ k0R,!F
this.results = results; [ )B@
} puk4D
_LLW{^V
public String toString(){ *YMXiYJR
StringBuilder buff = new StringBuilder YlxUx
VN1#8{
(); LH1BZ(5g
buff.append("{"); +X{cN5Y K
buff.append("count:").append(count); UX+?0 K
buff.append(",p:").append(p); iOE9FW|e
buff.append(",nump:").append(num); .kz(V5
buff.append(",results:").append (p}9^Y
:a#|
(results); #zh6=.,7
buff.append("}"); |2tSUOZ
return buff.toString(); QLxXp
} s2kGU^]y
"`H=AX0
} >IR`]
pU[a[
t>fA!K%{