Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 EtG)2)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &0TheY;srf
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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 ' ga2C\)
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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 =Ch#pLmH
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分页支持类: 19DW~kvYk
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java代码: c eX*|B@=
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package com.javaeye.common.util; w5Z3e^g
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import java.util.List; CaMG$X&O
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publicclass PaginationSupport { [8n4lE[)"
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publicfinalstaticint PAGESIZE = 30; Gz:a1-x
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privateint pageSize = PAGESIZE; 5 Da(DA
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privateList items; \~>#<@h
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privateint totalCount; zrM|8Cu
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privateint[] indexes = newint[0]; I`l<}M
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privateint startIndex = 0; ho. a93
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public PaginationSupport(List items, int M9nYt~vHX
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totalCount){ jLg4_N1SD
setPageSize(PAGESIZE); G.8ZISN/
setTotalCount(totalCount); jw)t"S/E
setItems(items); #Bjnz$KB
setStartIndex(0); Qpc>5p![3
} D]REZuHOI
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public PaginationSupport(List items, int Y`v&YcX;
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totalCount, int startIndex){ lDzVc`c
setPageSize(PAGESIZE); d!cx%[
setTotalCount(totalCount); li?Gb1
setItems(items); W=/B[@3'
setStartIndex(startIndex); tFCeE=4%
} MG|NH0k
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public PaginationSupport(List items, int `B~%TEvMh
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totalCount, int pageSize, int startIndex){ P=.W.oS
setPageSize(pageSize); P t$7U[N
setTotalCount(totalCount); hO8B]4=&*
setItems(items); a,.9eHf
setStartIndex(startIndex); y)2]:nD`B
} 9j/B3CjW
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publicList getItems(){ |dO1w.x/
return items; G9jtL$}E<
} ]4PG[9J@
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publicvoid setItems(List items){ /$E1!9J
this.items = items; g"xZ{k_3
} {v(3[7
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publicint getPageSize(){ gyIPG2d
return pageSize; b.F2m(e2
} aE+E'iL
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publicvoid setPageSize(int pageSize){ '(?@R5a
this.pageSize = pageSize; Xv9CD
} nZ]d[
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publicint getTotalCount(){ V'8
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return totalCount; %H54^Z<y
} `y4+OXZ^
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publicvoid setTotalCount(int totalCount){ 0W@C!mD~
if(totalCount > 0){ `KZ}smMA
this.totalCount = totalCount; r~X6qC
int count = totalCount / NGNn_1
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pageSize; Xo
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if(totalCount % pageSize > 0) lw7wvZD
count++; 0 }q/VH57
indexes = newint[count]; Q"KH!Bu%P
for(int i = 0; i < count; i++){ f_}55?i0
indexes = pageSize * K/altyj`
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} sf%=q$z
}else{ l#Iof)@#
this.totalCount = 0; F$.M2*9
} I3$v-OiL
} sD
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publicint[] getIndexes(){ rkVZP!7!
return indexes; F4*f_lP
} 9K)2OX;$w
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publicvoid setIndexes(int[] indexes){ %
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this.indexes = indexes; Mv_4*xVc
} Te;`-EL
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publicint getStartIndex(){ wEk9(|
return startIndex; /#blXI
} p<
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publicvoid setStartIndex(int startIndex){ .iw+#
if(totalCount <= 0) zdtzR<X
this.startIndex = 0; )V3G~p=0
elseif(startIndex >= totalCount) kIQMIL0+
this.startIndex = indexes T2k5\r8
}ZV$_
[indexes.length - 1]; 4!D!.t~r
elseif(startIndex < 0) iidK}<o
this.startIndex = 0; ]ko>vQ4]3
else{ { 2-w<t
this.startIndex = indexes $H?v
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[startIndex / pageSize]; e<q;` H
} %ePInpb
} F&Q:1`y
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publicint getNextIndex(){ &}6=V+J;
int nextIndex = getStartIndex() + ;vuok]@
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pageSize; 6*CvRb&
if(nextIndex >= totalCount) s3oK[:/
return getStartIndex(); !s5 _JO
else :Z,zWk1|
return nextIndex; 1--5ok
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} 21W>}I"0?
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publicint getPreviousIndex(){ k |M
int previousIndex = getStartIndex() - L ej3? k
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pageSize; %<P&"[F]v@
if(previousIndex < 0) ^dRB(E}|)
return0; ~r+;i,,X
else kz] qk15w
return previousIndex; rcAx3AK.
}
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抽象业务类 YDO#Q= q%
java代码: WUZusW5s
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/** Z
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* Created on 2005-7-12 *}Vg]3$4
*/ ?$%#y u#.
package com.javaeye.common.business; o^H.uBO{
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import java.io.Serializable; s@V4ny9x
import java.util.List; ~Cm_=[
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import org.hibernate.Criteria; Zg_ fec~6q
import org.hibernate.HibernateException; m>DBO|`
import org.hibernate.Session; DOyYy~Q
import org.hibernate.criterion.DetachedCriteria; v:|_!+g:
import org.hibernate.criterion.Projections; )$XcO]
import PS**d$ S
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org.springframework.orm.hibernate3.HibernateCallback; CN+[|Mz*p
import "K;f[&xO,o
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org.springframework.orm.hibernate3.support.HibernateDaoS Sjv_% C$
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upport; \$$DM"+:;H
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import com.javaeye.common.util.PaginationSupport; !o1+#DL)MU
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public abstract class AbstractManager extends n Hz Xp:"
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HibernateDaoSupport { I82GZL
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privateboolean cacheQueries = false; M8(N9)N
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privateString queryCacheRegion; hR(\ %p
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publicvoid setCacheQueries(boolean )G
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cacheQueries){ epXvk
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this.cacheQueries = cacheQueries; 5L!EqB>m;
} %=e^MN1
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publicvoid setQueryCacheRegion(String {_C2c{
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queryCacheRegion){ > &tmdE
this.queryCacheRegion = (.^KuXd
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queryCacheRegion; bWv2*XC
} *5m4j=-
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publicvoid save(finalObject entity){ ~T">)Y~+xI
getHibernateTemplate().save(entity); (J}tCqP
} OXDEU.
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publicvoid persist(finalObject entity){ K-<<s
getHibernateTemplate().save(entity); #:[^T,YD0
} q|h#J}\
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publicvoid update(finalObject entity){ >=O5=\`
getHibernateTemplate().update(entity); <Ukeq0
} Smg z}
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publicvoid delete(finalObject entity){ #7v=#Jco
getHibernateTemplate().delete(entity); Qv1<)&Ft<
} pm` f?Py
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publicObject load(finalClass entity, SJ*qgI?}T
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finalSerializable id){ `?=Y^+*!-
return getHibernateTemplate().load B5v5D[ o5
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(entity, id); rUn1*KWbE
} $-AG$1
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publicObject get(finalClass entity, 4m1@lnjp
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finalSerializable id){ yo^M>^P\N
return getHibernateTemplate().get L5DeLF+
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(entity, id); e5
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} tXfXuHa
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publicList findAll(finalClass entity){ !(A<
return getHibernateTemplate().find("from gkhmQd
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" + entity.getName()); ^i[bo3
} ,4mb05w;d
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publicList findByNamedQuery(finalString tfIUH'Ez>
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namedQuery){ YgV" *~
return getHibernateTemplate t9~Y
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().findByNamedQuery(namedQuery); #KUNZW
} XcFu:B
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publicList findByNamedQuery(finalString query, N1fPutl$a
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finalObject parameter){ Sc14F
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return getHibernateTemplate 0JE*| CtK
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().findByNamedQuery(query, parameter); q~. .Z Y`7
} ,8[R0wsBaz
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publicList findByNamedQuery(finalString query, zX8'OoEH*9
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finalObject[] parameters){ Y>2oU`ly,
return getHibernateTemplate ^]k=*>{
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().findByNamedQuery(query, parameters); P" aw--f(
} ^6@6BYf)
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publicList find(finalString query){ n#PXMD*
return getHibernateTemplate().find Ug#EAV<m
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(query); yk0^m/=C(
} T_ j0*A$
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publicList find(finalString query, finalObject @yNCWa~N
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parameter){ }hA)p:
return getHibernateTemplate().find Lvb'qZ6n
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(query, parameter); Pd+Wb3
} Ow0( q^H<
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public PaginationSupport findPageByCriteria KBI36=UV
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(final DetachedCriteria detachedCriteria){ eIcIl2
return findPageByCriteria ZdJQ9y
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Zt \3y
} Y;=GM:*H
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public PaginationSupport findPageByCriteria :DJL kMP
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(final DetachedCriteria detachedCriteria, finalint {!*dk
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startIndex){ >P}6/L
return findPageByCriteria Wb#ON|.2
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(detachedCriteria, PaginationSupport.PAGESIZE, /Py`a1
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startIndex); EouI S2e;a
} }F-,PSH
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public PaginationSupport findPageByCriteria ]RuH6d2d|
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(final DetachedCriteria detachedCriteria, finalint PEMuIYm$
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pageSize, ;y.<I&
finalint startIndex){ 08z?i
return(PaginationSupport) `08}y*E
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getHibernateTemplate().execute(new HibernateCallback(){ }g"K\x:Z
publicObject doInHibernate G(hzW%P
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(Session session)throws HibernateException { b?:SCUI
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); ,-)ww:
int totalCount = PG*FIRDb
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((Integer) criteria.setProjection(Projections.rowCount yHmNO*(
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()).uniqueResult()).intValue(); a;v;% rs
criteria.setProjection nm`}Z'&)
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(null); 9R N ge;*
List items = KV|ywcGhT
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criteria.setFirstResult(startIndex).setMaxResults kOV6O?h
;'oi7b
(pageSize).list(); 84c[ Z
PaginationSupport ps = 7jPn6uz>w
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new PaginationSupport(items, totalCount, pageSize, ?>iZ){0,
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startIndex); 89fl\18%
return ps; S%7%@Qs"%
} 1-}$sO c
}, true); +||[H)qym
} +\66; 7]s
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public List findAllByCriteria(final /i
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DetachedCriteria detachedCriteria){ 9S{?@*V
return(List) getHibernateTemplate z1LY|8$G
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().execute(new HibernateCallback(){ '?b.t2
publicObject doInHibernate 8zH/a
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(Session session)throws HibernateException { }\d3
Criteria criteria = $F~hL?"?
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}I
detachedCriteria.getExecutableCriteria(session); n$jf($*
return criteria.list(); V2*m/JyeB
} 5YgUk[J
}, true); 0u8(*?
} 5U.,iQ(d
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public int getCountByCriteria(final }9>X M
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DetachedCriteria detachedCriteria){ Bk8 '*O/)
Integer count = (Integer) ;/ao3Q
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getHibernateTemplate().execute(new HibernateCallback(){ zNQ|G1o
publicObject doInHibernate <P<^,aC/j
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(Session session)throws HibernateException { Lz;E/a}s
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); *,oZ]!
return ;@I}eZ,f$
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criteria.setProjection(Projections.rowCount 0%5x&vx'S
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()).uniqueResult(); \ /6m
} Ia>>b #h
}, true); me/ae{
return count.intValue(); P7p'j
} Nx"v|"
} JulxFjC
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用户在web层构造查询条件detachedCriteria,和可选的 YK|Y^TU^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /yj-^u\R
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PaginationSupport的实例ps。 O"x/O#66
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ps.getItems()得到已分页好的结果集 =v]eQIp
ps.getIndexes()得到分页索引的数组 "6%vVi6
ps.getTotalCount()得到总结果数 4C_-MJI
ps.getStartIndex()当前分页索引 blA]z!FU
ps.getNextIndex()下一页索引 h\^> s$
ps.getPreviousIndex()上一页索引 JPT VZ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R0*+GIRA(
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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 R!.HS0i.
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一下代码重构了。 _;+N=/l0
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我把原本我的做法也提供出来供大家讨论吧: 0\y@etb:mf
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首先,为了实现分页查询,我封装了一个Page类: _A.?:'-
java代码: U"v}br-kb
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/*Created on 2005-4-14*/ `N"fsE ma
package org.flyware.util.page; <XxFR
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/** WwDxZ>9jw
* @author Joa S
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* V
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*/ hOx">yki
publicclass Page { RKP->@Gs
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/** imply if the page has previous page */ s/K}]F
privateboolean hasPrePage; -ijQTB
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/** imply if the page has next page */ _r|$H_#
privateboolean hasNextPage; U{>eE8l
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/** the number of every page */ 7o+!Gts]
privateint everyPage; wQ,RZO3
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/** the total page number */ )Oz( <vxw
privateint totalPage; 'gojP
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/** the number of current page */ f6Wu+~|Y
privateint currentPage; X?.bE!3=
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/** the begin index of the records by the current '.@R_sj
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query */ 0\jOg
privateint beginIndex; 3Fn26Rij
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/** The default constructor */ |Tz4 xTK
public Page(){ q$`:/ ehw
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} ?Y'S
/
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/** construct the page by everyPage &hba{!`y
* @param everyPage WL}6YSC
* */ iEki<e/
public Page(int everyPage){ 7`tnoTUv
this.everyPage = everyPage; _A)<"z0E
} XI\aZ\v
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/** The whole constructor */ 9VN@M
public Page(boolean hasPrePage, boolean hasNextPage, <E
BgHD)
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int everyPage, int totalPage, %~ecrQ;
int currentPage, int beginIndex){ $YSD%/c
this.hasPrePage = hasPrePage; fwAN9zs
this.hasNextPage = hasNextPage; 4ij`
this.everyPage = everyPage; 5!Z+2Cu]
this.totalPage = totalPage; _:'m/K3Ee
this.currentPage = currentPage; NI(`o8fN
this.beginIndex = beginIndex; "`"j2{9|e!
} ^;s`[f|w
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/** n/8Kb.Vf
* @return Xx|&%b{{r
* Returns the beginIndex. ^l^_ K)tw*
*/ #s#z@F
publicint getBeginIndex(){ G-3.-
return beginIndex; B;;D(NH
} |-_5ouN.
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/** (4 {49b
* @param beginIndex d0 V>;Q
* The beginIndex to set. ^MJGY,r6b
*/ ;*W]]4fy
publicvoid setBeginIndex(int beginIndex){ u."fJ2}l0X
this.beginIndex = beginIndex; Q'+N72=
} 0dkM72p
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/** L''0`a. +S
* @return `6mHt6"h
* Returns the currentPage. faO8
&
*/ UWn}0:6t
publicint getCurrentPage(){ i8B%|[nm
return currentPage; rpEFyHorJ
} +zs6$OI]V
6eDIS|/
/** GYO\l.%V5y
* @param currentPage N0vd>b
* The currentPage to set. HqXo;`Yy}
*/ E;4Ns
publicvoid setCurrentPage(int currentPage){ 2hJ{+E.m
this.currentPage = currentPage; M+hc,;6
} jq0tMTb%L
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/** 5h:SH]tn8]
* @return ^2kWD8c*
* Returns the everyPage. Yn<0D|S;X
*/ U[A*A^$c}
publicint getEveryPage(){ Ab2g),;c
return everyPage; CY>NU
} rIb[gm)Rk
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/** u\e#_*>
* @param everyPage j^%i?BWw
* The everyPage to set. btOTDqG`a
*/ =H,cwSE+%
publicvoid setEveryPage(int everyPage){ 7t04!dD}
this.everyPage = everyPage; oo Z-T>$
} %UQ?k:aWp|
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/** ,\IqKRcYU
* @return Oq[E\8Wn
* Returns the hasNextPage. #Y5I_:k
*/ `90v~OF
publicboolean getHasNextPage(){ Eq8OAuN
return hasNextPage; ?J~JQe42
} b<F 4_WF
bg
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/** KFZ[gqW8YY
* @param hasNextPage T?\CAk>
* The hasNextPage to set. Q"Ec7C5eM
*/ 9iF e^^<ss
publicvoid setHasNextPage(boolean hasNextPage){ __ mtZ{
this.hasNextPage = hasNextPage; !%u#J:z2
} 'd t}i<
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/** MtYP3:
* @return
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* Returns the hasPrePage. *[SsvlFt
*/ H*\[:tPa
publicboolean getHasPrePage(){ .d"+M{I
return hasPrePage; oX}n"5o:
} R{[Q+y'E
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/** uWWv`bI>x
* @param hasPrePage P+b^;+\1s
* The hasPrePage to set. Oq2H>eW`f
*/ Iv<9})2K
publicvoid setHasPrePage(boolean hasPrePage){ z;/'OJ[.
this.hasPrePage = hasPrePage; .HQ<6k:
} og\XLJ}_
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[
/** v)d0MxSC
* @return Returns the totalPage. <=inogf
* o 4b{>x
*/ KB"iF}\P0
publicint getTotalPage(){ $0*47+f
return totalPage; MzG ryM-
} &!a2%%1#N
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/** ) ,hj7
* @param totalPage \Zv =?\
* The totalPage to set. dI!/:x
*/ v$i%>tQ\
publicvoid setTotalPage(int totalPage){ _B1uE2j9
this.totalPage = totalPage; J:lwq@u
} {@#L'i|
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} SNU
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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 ]-'9|N*}l
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个PageUtil,负责对Page对象进行构造: 2SJh6U
java代码: U(N$6{i_
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/*Created on 2005-4-14*/ 3b3cNYP
package org.flyware.util.page; E)hinH
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import org.apache.commons.logging.Log; oPy zk7{
import org.apache.commons.logging.LogFactory; ]R{"=H'
+2}(]J=-
/** ,&?q}M
* @author Joa tlERis
* y|Y3,s
*/ ~|9LWp_
publicclass PageUtil { #Q@6:bBzv
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privatestaticfinal Log logger = LogFactory.getLog erP>P
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(PageUtil.class); W{+0iAYnp
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/** %9/)
* Use the origin page to create a new page {@ y,
* @param page %gMpV
* @param totalRecords W-PZE|<
* @return T+nC>}*jgJ
*/ 0o|,& K
publicstatic Page createPage(Page page, int D:ugP,
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totalRecords){ _Af4ct;ng
return createPage(page.getEveryPage(), :3>yr5a7-
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page.getCurrentPage(), totalRecords); 5SL>q`t.bd
} pInWKj[y1
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/** 3t8H?B12ow
* the basic page utils not including exception /Z "
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/C"s_:m;3
handler fF>qU-
* @param everyPage YaZt+WA
* @param currentPage |~uzQU7
* @param totalRecords PBs<8xBx^
* @return page g**%J Xo
*/ *z"1MU
publicstatic Page createPage(int everyPage, int 7oe@bS/Z
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currentPage, int totalRecords){ !J=;Z9
everyPage = getEveryPage(everyPage); WQLL[{mhS
currentPage = getCurrentPage(currentPage); TJ[jZuT:
int beginIndex = getBeginIndex(everyPage, ptcLJ]+)
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currentPage); ]az}
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int totalPage = getTotalPage(everyPage, ,L{o,qzC
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totalRecords); \Tf{ui
boolean hasNextPage = hasNextPage(currentPage, UeQ9G
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totalPage); sR>;h /
boolean hasPrePage = hasPrePage(currentPage); 4`-?r%$,:
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returnnew Page(hasPrePage, hasNextPage, C$RAJ
everyPage, totalPage, SxW}Z_8x
currentPage, p@8^gc
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beginIndex); l6B ^sc*@
} txfwLqx
Pv-V7`{
privatestaticint getEveryPage(int everyPage){ lzy$.H"W
return everyPage == 0 ? 10 : everyPage; DET!br'z5
} VtzmY
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privatestaticint getCurrentPage(int currentPage){ YNJpQAuSn)
return currentPage == 0 ? 1 : currentPage; %c&Ah
} )|h;J4V
<,X+`m&
privatestaticint getBeginIndex(int everyPage, int ]b~2Dap
g.Caapy
currentPage){ h,'mN\6t
return(currentPage - 1) * everyPage; /yw\(|T
} 8@W/43K8-
`^bvj]>l
privatestaticint getTotalPage(int everyPage, int [OoH5dD
;p#Z :6
totalRecords){ -6~dJTm[t
int totalPage = 0; 0o=6A<#x
N]s7/s
if(totalRecords % everyPage == 0) vzyI::f?
totalPage = totalRecords / everyPage; i3 l #~
else %AEK[W+0
totalPage = totalRecords / everyPage + 1 ; KB,~u*~!
@Uj_+c
q
return totalPage; M*~v'L_sI
} H8<7#
:&1=8^B Y
privatestaticboolean hasPrePage(int currentPage){ nA_
zP4
return currentPage == 1 ? false : true; A D}}>v
} 22Y!u00D
#1jtprc
privatestaticboolean hasNextPage(int currentPage, SCh7O}
61+pryW%g
int totalPage){ K*_{Rs0P
return currentPage == totalPage || totalPage == _> |R-vQ8
V:F+HMBk
0 ? false : true; Ef_F#X0#
} L=$?q/=-
-M1~iOb
c6Yf"~TD0
} csFJ5
n<%=~1iY+
*t?~)o7
J+cAS/MYX
{Ukc D+.Y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 4l%?mvA^m
v`_i1h9p{
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 .e FOfV)
JhhUg
做法如下: Oa.f~|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ){Ciu[h
5v!DYx
的信息,和一个结果集List: ]w_
java代码: Ukh$`q}
ER;lkF`RF
/H%<oAjp6
/*Created on 2005-6-13*/ 0V>ESyae5
package com.adt.bo; X@bn??
QWzOp\+
import java.util.List; r(,= uLc
da9*9yN
import org.flyware.util.page.Page; (pT(&/\8
co$Hi9JE
/** :tjgg]
* @author Joa 409x!d~it
*/ _UH/}!nqB
publicclass Result { 2|0Qk&
G. -h=DT]
private Page page; q:2aPfo&
*;OJ~zT
private List content; +gbX}jF0%
daA47`+d
/** {8!ZKlB
* The default constructor {?@t/.4[W3
*/ ;o-\. =l
public Result(){ TbKP8zw{
super(); O?nPxa<
} wVvqw/j*f
P7'oXtW{o
/** KrdZEi vb
* The constructor using fields
}@rg5$W
* 9S:{
* @param page %k3NT~
* @param content ,>bGbx
*/ [)Z'N/;0
public Result(Page page, List content){ '!j #X_;
this.page = page; C=oM,[ESQ0
this.content = content; `2B*CMW{
} p4m^ ~e
1a($8>
/** ,2 zt.aqB
* @return Returns the content. <&qpl0U)Y
*/ P3>..fhoW
publicList getContent(){ S3ab0JM
return content; 0`VD!_`
} !G)mjvEe
/~o7Q$)-b
/** `y8
?=
* @return Returns the page. ~")hE%Kl}
*/ (R4PD
public Page getPage(){
sBP}n.#$
return page; _o@(wGeu#
} G$?|S@I,
4zo4H~@gk
/** ~q0I7M
* @param content [,OJX
N-4s
* The content to set. d\~p5_5.
*/ Q!4i_)rM
public void setContent(List content){ ${A5-
this.content = content; `3f_d}b
} -Z:]<;qU
/6+1{p
/** !cq=)xR
* @param page "C_T]%'Wm
* The page to set. !GlnQ`T
*/ 5x*5|8
publicvoid setPage(Page page){ f,Sth7y
this.page = page; ksB
} q+YuVQ-fx
} E
S#rs="
G{@C"H[$<
:7 qqjs
Jt##rVN
zq,iLoY[R
2. 编写业务逻辑接口,并实现它(UserManager, iP<k1#k
BQyvj\uJ
UserManagerImpl) j y7
java代码: 'M~BE\
Ze-MAt
NJn&>/vM
/*Created on 2005-7-15*/ aQ(`6DQv
package com.adt.service; Z} c'Bm(
_LJ5o_-N
import net.sf.hibernate.HibernateException; Hu<p?mF#
BX@pt;$ek7
import org.flyware.util.page.Page; ,/i_QgP
k/df(cs
import com.adt.bo.Result; :=rA Yc3]
FJO"|||Y'|
/** r8IX/ ,
* @author Joa oS~}TR:}
*/ C@*%AY
publicinterface UserManager { ` *>V6B3
"Kyifw?
public Result listUser(Page page)throws /nc~T3j
{*N^C@
HibernateException; .4wTjbO6
fJX\'Rc\
} +IG1IF
}KK2WJp#M
}0$mn)*k
vT?Q^PTO
.
3GnZR,L
java代码: Q(lku"U'
BR;QY1
%moJF1
/*Created on 2005-7-15*/ Iph3%RaE
package com.adt.service.impl; tC2N>C[N
8O;Vl
import java.util.List; 0eFb?Z0]
GP* +
import net.sf.hibernate.HibernateException; BEln6zj
$Z/klSEf
import org.flyware.util.page.Page; hF2/
y.:P
import org.flyware.util.page.PageUtil; Yy]T
J
:v`o6x8
import com.adt.bo.Result; K>kLUcC7Z
import com.adt.dao.UserDAO; _WKJ<dB<
import com.adt.exception.ObjectNotFoundException; !/947Rn
import com.adt.service.UserManager; DMB"Y,
*9J1$Wa
/** hL0]R,t;'
* @author Joa (zY * 0lN
*/ ,~- ?l7
publicclass UserManagerImpl implements UserManager { v51EXf
qtHfz"p
private UserDAO userDAO; F<5nGx cC
"9qp"%
/** ):krJ+-/y
* @param userDAO The userDAO to set. cqEHYJ;B
*/ S."7+g7Ar
publicvoid setUserDAO(UserDAO userDAO){ I0DM=V>;
this.userDAO = userDAO; hm3jpWi8
} r=qLaPG
yIOLs}!SF
/* (non-Javadoc) qbXz7s*{
* @see com.adt.service.UserManager#listUser fE^uF[-7?
job[bhK'Jt
(org.flyware.util.page.Page) sAVefL?
*/ @&5 A&(
public Result listUser(Page page)throws 4b4QbJ$
aM$\#Cx
HibernateException, ObjectNotFoundException { 1i
u =Y
int totalRecords = userDAO.getUserCount(); +3Y!xD?=
if(totalRecords == 0) h'l^g%;
throw new ObjectNotFoundException !h>D;k6 e
a+41Ojv (
("userNotExist"); .jU Z
page = PageUtil.createPage(page, totalRecords); "<*awWNI
List users = userDAO.getUserByPage(page); -u|l}}bh
returnnew Result(page, users); -l
"U"U"F
} 0 O~p7D
M/{g(|{
} :M j_2
kM!V.e[g
?>V6P_r>
B;!f<"a8
+yWR#[`n
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 RZO5=L9E
6Nt$ZYS
询,接下来编写UserDAO的代码: (;}tf~~r
3. UserDAO 和 UserDAOImpl: TFy7HX\Oq
java代码: F6W}mMZH/N
Pd~MiyO;K
2zK"*7b?
/*Created on 2005-7-15*/ &x0C4Kh
package com.adt.dao; f7J,&<<5w
iITp**l
import java.util.List; C0fmmI0z~
YsP/p-
import org.flyware.util.page.Page; !8*McOI
'L{p,
import net.sf.hibernate.HibernateException; ~Fw<eY
] TSg!H
/** (KTnJZ
* @author Joa ioV_oR9I
*/ -(>qu.[8=
publicinterface UserDAO extends BaseDAO { xhw-2dl*H
6z?gg3GV
publicList getUserByName(String name)throws ~O:
U|&
|)o#|Qo
HibernateException; EvE,Dm?h
WJ+>e+
publicint getUserCount()throws HibernateException; Rg* J}
$
[7 Vgs
publicList getUserByPage(Page page)throws X
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@u)
'yS
HibernateException; B8m_'!;;
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} VXm[-
h1+hds+
7byCc_,
8~ #M{}
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java代码: LK}-lZ`
i
['[KR
BJL
pm USF #u
/*Created on 2005-7-15*/
u1cu]Sj0
package com.adt.dao.impl; 5]"SGP
u@=?#a$$
import java.util.List; 9vI]LfP
^bUxLa[.
import org.flyware.util.page.Page; *Oo &}oAj
}nud
import net.sf.hibernate.HibernateException; NQ9Ojj{#
import net.sf.hibernate.Query; w#(RW7":F
RY=1H
import com.adt.dao.UserDAO; b2kWjg.4
0oU=RbC
/** Lw*]EG|?
* @author Joa )%Ru#}1X6
*/ a<m-V&4x
public class UserDAOImpl extends BaseDAOHibernateImpl s_eOcm
/\=MBUN
implements UserDAO { |}[nH>
4nkE IZ
/* (non-Javadoc) v27Ja .tA
* @see com.adt.dao.UserDAO#getUserByName 7@~tVxB;
%f&< wC
(java.lang.String) .Q&rfH3
*/ I,O#X)O|i
publicList getUserByName(String name)throws /#S>sOg2xq
5j^NV&/_
HibernateException { C3VLV&wF
String querySentence = "FROM user in class :b/jNHJU
~xyw>m+o.
com.adt.po.User WHERE user.name=:name";
k0H#:c}
Query query = getSession().createQuery z.)p
P'CJo
u&]vd /
(querySentence); N[U9d}Zv
query.setParameter("name", name); >dQ K.CG
return query.list(); Bct"X#W|&
} SH8/0g?
hI|)u4q
/* (non-Javadoc) onte&Ed\
* @see com.adt.dao.UserDAO#getUserCount() UQT'6* !
*/ .q;ED`G
publicint getUserCount()throws HibernateException { .ve *Vp
int count = 0; +MUwP(U=w
String querySentence = "SELECT count(*) FROM xxa} YIe8
O}Le]2'
user in class com.adt.po.User"; w'ybbv{c
Query query = getSession().createQuery =AOWeLk*G
Xl%0/o
(querySentence); 9E1W|KE
count = ((Integer)query.iterate().next IA*KaX2S<
x?r1s#88>
()).intValue(); K7`YJp`i
return count; TGV
} S~F`
7#-y-B]l
/* (non-Javadoc) tRfm+hqRZ
* @see com.adt.dao.UserDAO#getUserByPage .FP$ IWt/1
5/I_w0
(org.flyware.util.page.Page) WDx
Mo`zT
*/ ?Zcj}e.r
publicList getUserByPage(Page page)throws KMjg;!y
RKTb'3H
HibernateException { B0)]s<<
String querySentence = "FROM user in class `M@Ak2gcR+
0 bSA_
com.adt.po.User"; cF+ X,]=6
Query query = getSession().createQuery '$m7ft}
8 i0
(querySentence); N$ alUx*
query.setFirstResult(page.getBeginIndex()) O/OiQ^T
.setMaxResults(page.getEveryPage()); py<_HyJ
return query.list(); \2X$C#8E
} n:#TOU1ix<
F0dI/+
} 3$p#;a:=n
*l>0t]5YH
i~yX tya
(#Mp 5C'X
eD;6okdP
至此,一个完整的分页程序完成。前台的只需要调用 ' UMFS
]~c+'E`
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ruaur]
RR|\- 8;
的综合体,而传入的参数page对象则可以由前台传入,如果用 \54}T4R
Un@\kAY
webwork,甚至可以直接在配置文件中指定。 "{BqtU*.
xJ(:m<z
下面给出一个webwork调用示例: pyB~M9Bp/
java代码: S GcBmjP
sQ1jrkm
d53 L65[
/*Created on 2005-6-17*/ [*Ju3
package com.adt.action.user; dcq#TBo8
Q~,YbZ-7
import java.util.List; hR)2xz
-- k:a$Nt
import org.apache.commons.logging.Log; `T WN^0!]
import org.apache.commons.logging.LogFactory; <'m6^]:
import org.flyware.util.page.Page; clDHTj=~
@LX6hm*}
import com.adt.bo.Result; M] EsS^/X
import com.adt.service.UserService; lrEj/"M
import com.opensymphony.xwork.Action; `y!/F?o+!
>-cfZ9 {!
/** f~M8A.
* @author Joa
'3,\@4
*/ 0Xl%uF+w
publicclass ListUser implementsAction{ \cySWP[
'fW#7W
privatestaticfinal Log logger = LogFactory.getLog QGPw2Q
<+]f`c*Z
(ListUser.class); q&si%
_PXdzeI.
private UserService userService; 3C^1frF
~!:0iFE&H
private Page page; Dgi~rr1`'s
#}yTDBt
privateList users; 8 %Sb+w07
Y& {|Sw7?
/* ,E*R,'w
* (non-Javadoc) T{Zwm!s
* v%91k
* @see com.opensymphony.xwork.Action#execute() B@K[3
*/ {=JF=8@A
publicString execute()throwsException{ -G`.y?
Result result = userService.listUser(page); ;u-4KK
page = result.getPage(); i^2IW&+}e}
users = result.getContent(); F]=B'ZI
return SUCCESS; O6c\KFBSJ
} M<`|CVl
d ,F5:w&
/** #@//7Bf%
* @return Returns the page. ~L?nq@DL
*/ XW~bu2%{7"
public Page getPage(){ a W;aA'!
return page; !{%G0(Dv
} Vz:_mKA
By((,QpB
/** `/:cfP\
* @return Returns the users. Ot9V< D6h
*/ f(:1yl\a
publicList getUsers(){ 3N4.$#>#9@
return users; ([k7hUP
} 3LK%1+)4
$kz!zjC'
/** Fb_S&!
* @param page 2CLB1
* The page to set. GjQfi'vCk
*/ %}qbkkZ
publicvoid setPage(Page page){ WH$HI/%*m
this.page = page; 5cTY;@@
} ^R_e
@.9I3E-=
/** v5$s#f<
* @param users x>3@R0A1:
* The users to set. ")`S0n5e
*/ q-&P=Yk
publicvoid setUsers(List users){ bhg}-dto
this.users = users; 2{o10eL
} V2 `>
]/|
8T5k-HwE
/** %a8&W
* @param userService {B{i(6C(
* The userService to set. j\2[H^
*/ n["
9|
publicvoid setUserService(UserService userService){ []}N
this.userService = userService; A,XfD} +:Z
} 2p< Aj!
} ?2`$3[ET-
aiux^V
[.cq{6-
>&K!VQ{g
5h^[^*A?
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, ti_u!kNv
bkv/I{C>?
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 +zO]N&
p:[LnL
么只需要: DeQDH5X"
java代码: 3%
vis\~^
dgc&[
T 33|';k
<?xml version="1.0"?> u''BP.Y S
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ==9ZFdf
!,bPe5?Ql
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +R\~3uj[7
|63Y
>U"
1.0.dtd"> Bc
^4 T1
z`#_F}v,m/
<xwork> 5~}!@yzc
nNR:cGfG
<package name="user" extends="webwork- d*-Xuv
=AkX4k
interceptors"> x_:hii?6V
nVOqn\m-
<!-- The default interceptor stack name v33T @
Eo=HNe
--> o#{#r@,i
<default-interceptor-ref kL;t8{n
{ymb\$f
name="myDefaultWebStack"/> CeW7Ym
p":zrf'(6
<action name="listUser" U[fSQ`&D
O),I[kb
class="com.adt.action.user.ListUser"> vLn> 4SK
<param >q9{
0k1MKzi Q
name="page.everyPage">10</param> MSY N1
<result $u5.!{Wq?
,nYZxYLf+
name="success">/user/user_list.jsp</result> ` d`&R.'
</action> !-(J-45
^
f{qJ[,
</package> Q8Te'1Ln!
l1RlYl5
</xwork> `|,tCM&-
r@|ZlM@O
l<N?' &
-$R5
P"Rk?lL
cx:jUsb6
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 rWe
8D/oc
B;c=eMw
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。 *vs~SzF$
"1%*'B^}bw
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 cYD1~JX.
n/-N;'2J
{6tx,; r(F
R=86w_
<PQRd
我写的一个用于分页的类,用了泛型了,hoho 8Mb$+^zU
M6x;BjrV
java代码: Y[,U_GX/R
>fwlg-
Eq7gcDQ
package com.intokr.util; G>j"cj
+V89J!7
import java.util.List; n|Ma&qs
gTD%4V
/** STRyW Ml
* 用于分页的类<br> ZjavD^ky
* 可以用于传递查询的结果也可以用于传送查询的参数<br> HnK/A0jM
* [Ekgft&
* @version 0.01 5j1 IH,yW
* @author cheng p1?J
*/ +1f{_v
public class Paginator<E> { f>4+,@G
privateint count = 0; // 总记录数 ds')PIj
privateint p = 1; // 页编号 d-i&k(M
privateint num = 20; // 每页的记录数 {4)5]62>u
privateList<E> results = null; // 结果 :z124Zf
WiwwCKjSa
/** vT}pbOTh
* 结果总数 NIL^UN}
*/ 10TSc
j
publicint getCount(){ bY&YSlO
return count; `7$Oh{67
} v6(,Ax&
^EUQ449<p
publicvoid setCount(int count){ ^CX,nj_(
this.count = count; /Sh4pu"'
} *fOIq88
MIJ%_=sm4:
/** 8ZzU^x
* 本结果所在的页码,从1开始 >:fJhF@
* 9XY|V<}
* @return Returns the pageNo. roL]v\tr
*/ ^
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publicint getP(){ XSls]o
s
return p; -MsuBf
} Ic_t c
N6f%>3%1|.
/** R+x%r&L5F
* if(p<=0) p=1 LsUFz_
* 739l%u }<
* @param p 8Q)y%7{6
*/ ?n73J wH
publicvoid setP(int p){ a6OrE*x:D
if(p <= 0) 7dsnv)(v
p = 1; ws na5D6i
this.p = p; L5TNsLx (
} '1qAZkz
fCs\Q
/** Q=MCMe
* 每页记录数量
$o{F
*/ ` 3vN R"
publicint getNum(){ e(4bx5<*
return num; =/M$
<+
} zww?
R^F7a0"
/** ?Of{c,2 .
* if(num<1) num=1 n,1NJKX
*/ \qRjXadj
publicvoid setNum(int num){ nqUH6(
if(num < 1) B/:>{2cm
num = 1; ~7KynE
this.num = num; gE-lM/w
}
zd.1
z[_R"+
/** s=3EBh
* 获得总页数 'JJ1#kKa
*/ LZ3rr-
publicint getPageNum(){ #wq;^)>
return(count - 1) / num + 1; F<H`8*q9
} %'$cH$%~J
Ma
n^\gkCi
/** b0rt.XB
* 获得本页的开始编号,为 (p-1)*num+1 =]2
b8
*/ l;.[W|
publicint getStart(){ zDKLo 3:
return(p - 1) * num + 1; )^V5*#69D
} E5v|SFD
#J'Z5)i|
/** D>,$c
* @return Returns the results. DtI%-I.
*/ rin >r0o
publicList<E> getResults(){ iA5*
_tK5
return results; 1gf/#+$\
} w}]3jc84
])3lH%4-
public void setResults(List<E> results){ _.oRVYK/
this.results = results; &h_d|8
} 9}? 5p]%
UEx(~>
public String toString(){ \1eKY^)2
StringBuilder buff = new StringBuilder dn:|m^<)
hVTyv"
(); \=
)[
buff.append("{"); (\[jf39e
buff.append("count:").append(count); 3D[:Rf[
buff.append(",p:").append(p); ROlzs}
buff.append(",nump:").append(num); 9;m#>a@Y
buff.append(",results:").append Cb!`0%G
NzwGc+\7}
(results); W0p#Y h:{_
buff.append("}"); >@q2FSMf
return buff.toString(); VO\S>kw
} #!K~_DL
jn5=N[hd
} +c~O0U1
2J>A;x_?
>=]NO'?O