Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Zg;Ht
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 wqn}t]
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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 y?s#pSX;N
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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 f;W>:`'
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分页支持类: ])T_&%
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java代码: }~Y#N
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package com.javaeye.common.util; 9fb"R"(M
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import java.util.List; 0>?78QL9<
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publicclass PaginationSupport { ;Q8rAsf9
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publicfinalstaticint PAGESIZE = 30; 1j^FNg~
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privateint pageSize = PAGESIZE; SJI+$L\'
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privateList items; CbRl/ 68HY
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privateint totalCount; h3L{zOff
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privateint[] indexes = newint[0]; cd*F;h
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privateint startIndex = 0; A?OaP
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public PaginationSupport(List items, int bX]$S 5c_u
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totalCount){ #%tN2cFDN
setPageSize(PAGESIZE); zFV?,"\r
setTotalCount(totalCount); ?IV3"\5
setItems(items); bQ2 '*T
setStartIndex(0); uYwJ[1C
} &mp@;wI6@
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public PaginationSupport(List items, int -J*jW
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totalCount, int startIndex){ owc#RW9 7
setPageSize(PAGESIZE); > jvi7
setTotalCount(totalCount); '=vD!6=0@
setItems(items); ng[ZM);
setStartIndex(startIndex); R`|GBVbv
} ~I)\d/7o
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public PaginationSupport(List items, int 6~0.YZ9
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totalCount, int pageSize, int startIndex){ k
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setPageSize(pageSize); :Keek-E`e=
setTotalCount(totalCount); Doy7prKI8
setItems(items); Obu>xK(
setStartIndex(startIndex); x+7jJ=F
} gG.b=DvzY
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publicList getItems(){ !j?2HlIK+
return items; YTpO4bX
} R nf$
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publicvoid setItems(List items){ ,0=:06l
this.items = items; @dCoh-Q3
} @'EU\Y\l
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publicint getPageSize(){ vrD]o1F
return pageSize; W[Ro)
} xTW$9>@\m
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publicvoid setPageSize(int pageSize){ !bG%@{W T
this.pageSize = pageSize; u%vq<|~-
} Q<V?rPAcx
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publicint getTotalCount(){ -HU5E>xG
return totalCount; P p[?E.]P
} ,9W|$2=F
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publicvoid setTotalCount(int totalCount){ =FXZcP>h
if(totalCount > 0){ @<O
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this.totalCount = totalCount; D"m]`H
int count = totalCount / 'e;]\<
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pageSize; _f u?,
if(totalCount % pageSize > 0) 2\M^_x$N
count++; aoh"<I%]>4
indexes = newint[count]; uMToVk`Uv
for(int i = 0; i < count; i++){ J
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indexes = pageSize * x2\,n
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} V3NQij(
}else{ #,1Kum
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this.totalCount = 0; $ Aw"?&d"
} E
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} r_f?H@ v
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publicint[] getIndexes(){ {f\/2k3
return indexes; ;{79d8/=
} tB_GEt2M
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publicvoid setIndexes(int[] indexes){ $]eITyC`P
this.indexes = indexes; Ap{p_~~iJ
} a'zf8id
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publicint getStartIndex(){ Quy&CV{@
return startIndex; |Fk>NX
} w]hs1vch
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publicvoid setStartIndex(int startIndex){ )B86
if(totalCount <= 0) -lL(:drn
this.startIndex = 0; 0Z{f!MOh
elseif(startIndex >= totalCount) RjY(MSc
this.startIndex = indexes .mzy?!w0q
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[indexes.length - 1]; VL5GX(
elseif(startIndex < 0) o.ntzN
this.startIndex = 0; [;`B
else{ TzT(aWP"
this.startIndex = indexes v"VpE`z1#
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[startIndex / pageSize]; 82.::J'e
} J|-X?V;ZW
} Z6eM~$Y
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@
publicint getNextIndex(){ B zmmE2~*
int nextIndex = getStartIndex() + LE!xj 0
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pageSize; qU(,q/l
if(nextIndex >= totalCount) YL_M=h>P
return getStartIndex(); | N%?7PZ(
else fz[o;GTc
return nextIndex; ]o18oY(
} #"J8]3\F
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publicint getPreviousIndex(){ t'e1r&^:r~
int previousIndex = getStartIndex() - 038|>l-9[
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pageSize; kcg{z8cd'r
if(previousIndex < 0) zO BLF|L=
return0; e5/f%4YX
else `52+.*J+%
return previousIndex; +yvtd]D$2W
} P;7JK=~k
q#RUL!WF7U
} lxIoP
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抽象业务类 ,Jm2|WKH
java代码: jlvh'y`
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/** {t<E*5N]a
* Created on 2005-7-12 ~:`5Y"Av:
*/ EDQKb TaPt
package com.javaeye.common.business; v?Z30?_&h
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import java.io.Serializable; TR;" &'#k
import java.util.List; or~2r8
}HB>Zb5
import org.hibernate.Criteria; 3q'["SS
import org.hibernate.HibernateException; 0_F6t-
import org.hibernate.Session; w; [ndZCY7
import org.hibernate.criterion.DetachedCriteria; BvQMq5&
import org.hibernate.criterion.Projections; 1b^e4
import rC`pTN
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org.springframework.orm.hibernate3.HibernateCallback; U"nk AW
import S T#9auw
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org.springframework.orm.hibernate3.support.HibernateDaoS tB S+?N
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upport; +,7nsWV
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import com.javaeye.common.util.PaginationSupport; O;zq(/,-l
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public abstract class AbstractManager extends .|\}]O`
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HibernateDaoSupport { 'q3<R%^Q
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privateboolean cacheQueries = false; RT+pB{Y
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privateString queryCacheRegion; W|X=R?*ZK
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publicvoid setCacheQueries(boolean Fru&-T[
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cacheQueries){ <}uhKp>*
this.cacheQueries = cacheQueries; ~Up5 +7k@
} -!o*A>N
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publicvoid setQueryCacheRegion(String (G1KMy
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queryCacheRegion){ @:,B /B;
this.queryCacheRegion = f.yvKi.Cm
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queryCacheRegion; ,>
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} [3K& cX}B
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publicvoid save(finalObject entity){ o,r72>|
getHibernateTemplate().save(entity); ?04jkq&
} ^(+ X|t
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publicvoid persist(finalObject entity){ qLjLfJJ2
getHibernateTemplate().save(entity); u-s*3Lg&
} k|hy_? *
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publicvoid update(finalObject entity){ 6Qc
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getHibernateTemplate().update(entity); !
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}
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publicvoid delete(finalObject entity){ Ew<
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getHibernateTemplate().delete(entity); 'c7'iDM
} 8'>yB
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publicObject load(finalClass entity, g5&ZXA
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finalSerializable id){ /1y\EEc
return getHibernateTemplate().load B~ ?R 6
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(entity, id); t.rlC5
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} eoj(zY3
} yb"/jp
publicObject get(finalClass entity, tZXq<k9
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finalSerializable id){ ;W 3#q:
return getHibernateTemplate().get O#_\@f#[
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(entity, id); ge#0Q L0K
} /4I9Elr
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publicList findAll(finalClass entity){ uQhI)
return getHibernateTemplate().find("from `uwSxt
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" + entity.getName()); W-RqooEv
} lRANXM
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publicList findByNamedQuery(finalString $6l^::U
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namedQuery){ :R'={0Jg
return getHibernateTemplate 2^X<n{0N)
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().findByNamedQuery(namedQuery); pP-L{bT
} (VM.]B<
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publicList findByNamedQuery(finalString query, ,Mr_F^|
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finalObject parameter){ P<CPA7K
return getHibernateTemplate jX7;hQ+P
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().findByNamedQuery(query, parameter); FrsXLUY
} &c^tJ-s
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publicList findByNamedQuery(finalString query, /EW=OZ/
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finalObject[] parameters){ A I v
return getHibernateTemplate OwN~-).%-
8 \"A-+_Q
().findByNamedQuery(query, parameters); I]z4}#+cX
} hg7_ZjO
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publicList find(finalString query){ 3:aj8F2
return getHibernateTemplate().find !lL~#l:F
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(query); .wO-2h{Q
} 'kSm}}y
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publicList find(finalString query, finalObject ?>1wZ
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parameter){ Ou_2UT
return getHibernateTemplate().find Obx!>mI^6
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(query, parameter); rA|&G'
} 58t_j54
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public PaginationSupport findPageByCriteria $WiUoS
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(final DetachedCriteria detachedCriteria){ -C2[ZP-
return findPageByCriteria +V9 (4la
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); L0R$T=~%)
} %KPQ|^WE
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public PaginationSupport findPageByCriteria #h#_xh'
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(final DetachedCriteria detachedCriteria, finalint Xb~i?T;f
"H9q%S,FH
startIndex){ 6"9(ce
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return findPageByCriteria K}DrJ/s
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(detachedCriteria, PaginationSupport.PAGESIZE, mLV0J '
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startIndex); Qoa&]]
} uvRX{q4
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public PaginationSupport findPageByCriteria I%jlM0ZUI"
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(final DetachedCriteria detachedCriteria, finalint $T_>WUiK
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pageSize, jItVAmC=i
finalint startIndex){ :<H4hYt2
return(PaginationSupport) N>iNz[a
q
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getHibernateTemplate().execute(new HibernateCallback(){ _=9m[
publicObject doInHibernate $k+XH+1CW
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(Session session)throws HibernateException { 09=w
Criteria criteria = .dn#TtQv
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detachedCriteria.getExecutableCriteria(session); u
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int totalCount = /A-VT
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((Integer) criteria.setProjection(Projections.rowCount k_nQmU>
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()).uniqueResult()).intValue(); R*H-QH/H1
criteria.setProjection &srD7v9M8
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(null); ex.^V sf_
List items = lm*C:e)4A
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criteria.setFirstResult(startIndex).setMaxResults NAO0b5-h
5^{ I}Q
(pageSize).list(); <.{OIIuk
PaginationSupport ps = T[-Tqi NT
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new PaginationSupport(items, totalCount, pageSize, _z\qtl~3
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startIndex); /Ri-iC >
return ps; 6%V#_]
} ~ymSsoD^
}, true); J&L#^f*d
} 55Xfu/hQ
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public List findAllByCriteria(final <.ZD.u
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DetachedCriteria detachedCriteria){ `j'gt&
return(List) getHibernateTemplate 6ZQ$5PY
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().execute(new HibernateCallback(){ of'H]IZ
publicObject doInHibernate U%K gLg#
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(Session session)throws HibernateException { JmuoYl f|
Criteria criteria = g@m__
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detachedCriteria.getExecutableCriteria(session); /S9n!H:MT
return criteria.list(); &-KQ
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} {~V_6wY g
}, true); 1]aya(
} ,w,)n^
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public int getCountByCriteria(final 6-\C?w
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DetachedCriteria detachedCriteria){ UdFYG^i
Integer count = (Integer) /+m7J"Km
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getHibernateTemplate().execute(new HibernateCallback(){ BQ{'r^u
publicObject doInHibernate R4XcWx*pQ
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(Session session)throws HibernateException { &>Z p}.V
Criteria criteria = mFyYn,Mu|
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detachedCriteria.getExecutableCriteria(session); !H4uc
return CYNpbv
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criteria.setProjection(Projections.rowCount _mDvRFq
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()).uniqueResult(); %sS7o3RW\
} zU#
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}, true); Yt;@@xe&
return count.intValue(); mZ.E;X& ,*
} t`0(5v
} ^ |>)H
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用户在web层构造查询条件detachedCriteria,和可选的 %/wfY Rp*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @_?8I_\:
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PaginationSupport的实例ps。 j*jq2u
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ps.getItems()得到已分页好的结果集 "HbrYYRb'
ps.getIndexes()得到分页索引的数组 s`,. &
ps.getTotalCount()得到总结果数 fQ,(,^!;
ps.getStartIndex()当前分页索引 9'!I6;M
ps.getNextIndex()下一页索引 4\Cb4jq%/
ps.getPreviousIndex()上一页索引 <~Tfi*^+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]TKM.[[
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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 H @8 ;6D
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一下代码重构了。 /J'dG%
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我把原本我的做法也提供出来供大家讨论吧: Y&DC5T]
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首先,为了实现分页查询,我封装了一个Page类: <txzKpM
java代码: 5$f*fMd;
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/*Created on 2005-4-14*/ As*59jkB
package org.flyware.util.page; Q_n9}LanP
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/** V~qlg1h
* @author Joa cx(b5Z
* 0)3*E)g{
*/ agW#"9]WM
publicclass Page { zf^F.wW
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/** imply if the page has previous page */ ppM^&6x^
privateboolean hasPrePage; '^.}5be&
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/** imply if the page has next page */ &:*|K xX
privateboolean hasNextPage; ?\Z-3l%M
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/** the number of every page */ 9S[Tan|
privateint everyPage; ;/-#oW@gQ
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/** the total page number */ b."1p7'
privateint totalPage; 3:WXrOl
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/** the number of current page */ sp$W=Wu7
privateint currentPage; GPnSdGLC
FzGla} )
/** the begin index of the records by the current nLjo3yvV..
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query */ dq
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privateint beginIndex; u.sn"G-c
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/** The default constructor */ 4d0<uB&v'
public Page(){ y|@=j~}Zq
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} s*DDO67\W
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/** construct the page by everyPage oXkxd3
* @param everyPage *n%J#[e(
* */ P9D'L{yS/x
public Page(int everyPage){ Wc)f:]7
this.everyPage = everyPage; +Ss|4O}'
} (PN!k0Y
`Z0#IeX=
/** The whole constructor */ ,HdFE|
public Page(boolean hasPrePage, boolean hasNextPage, <C_FI` wk
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K)"cwk-
int everyPage, int totalPage, eqze7EY
int currentPage, int beginIndex){ Ng3 MfbFG
this.hasPrePage = hasPrePage; UN}jpu<h
this.hasNextPage = hasNextPage; xd H*[
this.everyPage = everyPage; ]OOL4=b
this.totalPage = totalPage; 0oi
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this.currentPage = currentPage; \'40u|f
this.beginIndex = beginIndex; RT)*H>|
} '
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/** V/G'{ q
* @return nEM>*;iE
* Returns the beginIndex. 8?r
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*/ a|im DY_-j
publicint getBeginIndex(){ @E$PjdB5M
return beginIndex; AhARBgf<
} qe:,%a-9
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/** &V&0kp@+
* @param beginIndex 0iX;%SPYz
* The beginIndex to set. \Podyh/;?
*/ ^.J
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publicvoid setBeginIndex(int beginIndex){ O9k9hRE]z
this.beginIndex = beginIndex; aMFUJrXo
} n(b(H`1n
##!)}i
/** wKCHG/W
* @return y$At$i>u
* Returns the currentPage. x.+}-(`W#~
*/ !RnO{FL
publicint getCurrentPage(){ rQbL86+
return currentPage; *Ki ],>_~
} 4l$(#NB<
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/** i(JBBE"
* @param currentPage "S43:VH
* The currentPage to set. KFd"JtPg
*/ ?s("@dz_
publicvoid setCurrentPage(int currentPage){ "}]1OL S V
this.currentPage = currentPage; Yo
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} }xHoitOD
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/** ~n84x
* @return .foM>UOY
* Returns the everyPage. '@ M
*/ >yn%.Uoh@
publicint getEveryPage(){ 9LGJ -gL
return everyPage; 0!rU,74I=
} H'$g!Pg
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/** !p1OBS|
* @param everyPage Gv}*Tw$
* The everyPage to set. 7{:| )
*/ R R><so%
publicvoid setEveryPage(int everyPage){ "2X=i`rTi
this.everyPage = everyPage; l,*v/95h
} SU9#Y|I
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/** k=O2s'F`
* @return )kl| 5i
* Returns the hasNextPage. Mu18s}
*/ 3mgFouX2x,
publicboolean getHasNextPage(){ vt[4"eU
return hasNextPage; 8h~v%aZ1
} j[yGfDb
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/** sf]y\_zU
* @param hasNextPage #"6(Q2|
l
* The hasNextPage to set. EW1L!3K
*/ s@f4f__(]
publicvoid setHasNextPage(boolean hasNextPage){ l0g#&V--
this.hasNextPage = hasNextPage; rB|D^@mG
} 7Rj!vj/
,*r"cmz
/** *~fZ9EkD
* @return |^Z1 D TAw
* Returns the hasPrePage. L*9^-,
*/ n6[bF"v
publicboolean getHasPrePage(){ r^&{0c&o
return hasPrePage; 46*o_A,"
} Ywt_h;:
8UoMOeI3
/** cn=~}T@~Z
* @param hasPrePage l2=.;7IV
* The hasPrePage to set. 3~BL!e,
*/ }#q9>gx
publicvoid setHasPrePage(boolean hasPrePage){ -[v:1\Vv
this.hasPrePage = hasPrePage; O1coay
}
"=H7p3
#;a
1=8H
/** UKQ,]VC
* @return Returns the totalPage. f!*b8ND^R
* 5SK{^hw
*/ ,v$gQU2
publicint getTotalPage(){ X}_}`wIn
return totalPage; (80]xLEBL
} 31wact^
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/** NDU,9A.P
* @param totalPage
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* The totalPage to set. rOB-2@-
*/ xzy7I6X
publicvoid setTotalPage(int totalPage){ ,Vt7Kiu
this.totalPage = totalPage; ' G-]>
} c}Y(Myd
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} Qwk
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>c\'4M8Cz
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ]~87v
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个PageUtil,负责对Page对象进行构造: D<#+ R"
java代码: `.Y["f
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/*Created on 2005-4-14*/ [L|H1ll
package org.flyware.util.page; AGn:I??
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import org.apache.commons.logging.Log; 9]VUQl9gh
import org.apache.commons.logging.LogFactory; >z
h
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/** ;)5d
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* @author Joa X7{ueP#L
* Q4TI '/
*/ EkEM|<GNd
publicclass PageUtil { AASw^A3p
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privatestaticfinal Log logger = LogFactory.getLog %z J)mOu
NM/?jF@j*
(PageUtil.class); II)\rVP5
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/** IBf&'/ 8\
* Use the origin page to create a new page rv&(yA
* @param page S$+vRX7
* @param totalRecords ,4jkTQ*@2
* @return <G{m=
*/ yd`xmc)
publicstatic Page createPage(Page page, int v6HBO#F'V{
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totalRecords){ /lx\9S|
return createPage(page.getEveryPage(), hkJ4,.
?7@B$OlU
page.getCurrentPage(), totalRecords); k)b}"' I
} KFdV_e5lU
)~T)$TS
/** _jR%o1Y}
* the basic page utils not including exception dfiA- h
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handler {^Vkxf]
* @param everyPage
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* @param currentPage V2,54YE
* @param totalRecords U voX\
* @return page GX&BUP\
*/ =_\5h=`Yx
publicstatic Page createPage(int everyPage, int 5CueD]
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currentPage, int totalRecords){ 4cRF3$amd
everyPage = getEveryPage(everyPage); $}jp=?,t
currentPage = getCurrentPage(currentPage); 7$<.I#x
int beginIndex = getBeginIndex(everyPage, wXMKQ)$(
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currentPage); Q`4=
int totalPage = getTotalPage(everyPage, F.HD;C-;(
V'#dY~E-P
totalRecords); _~&6Kb^*
boolean hasNextPage = hasNextPage(currentPage, *$Z}v&-0k
9s6@AJf
totalPage); II3)Cz}xRG
boolean hasPrePage = hasPrePage(currentPage); $/Gvz)M
VJDF/)X3$
returnnew Page(hasPrePage, hasNextPage, >E|@3g
+2
everyPage, totalPage, GRB/N1=
currentPage, `$ZX]6G
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beginIndex); MGfDxHg]
} @HxEp;*NH"
%2f``48#
privatestaticint getEveryPage(int everyPage){ oN)l/"%C7/
return everyPage == 0 ? 10 : everyPage; =SB#rCH
} {^i7 3}@O
X]U,`oE)9
privatestaticint getCurrentPage(int currentPage){ Q g"hN
return currentPage == 0 ? 1 : currentPage; hF s:9
} 01g=Cg
>N@tInE
privatestaticint getBeginIndex(int everyPage, int K}tl,MMU
/1F%w8Iqh
currentPage){ %I9{)'+@x
return(currentPage - 1) * everyPage; X|q&0W=
} #:s*)(Qn
[4"1TyW
privatestaticint getTotalPage(int everyPage, int [mn@/qf
AqB5B5}
totalRecords){ WjW+EF8(
int totalPage = 0; 0^az<!!O#
:tp2@*]9Z
if(totalRecords % everyPage == 0) =@AWw:!:,
totalPage = totalRecords / everyPage; V&;1n
else J 05@SG':
totalPage = totalRecords / everyPage + 1 ; a|SgGtBtT4
Rq )&v*=
return totalPage; [9(tIb!x
} jl;_lcO
n1m[7s.[&
privatestaticboolean hasPrePage(int currentPage){ F B9PIsFS
return currentPage == 1 ? false : true; ;,[6 n|M
} z6ISJb
DZ92;m
privatestaticboolean hasNextPage(int currentPage, k"&loh
'DO^ ($N
int totalPage){ _ui03veA1
return currentPage == totalPage || totalPage == 5XySF #
`E+)e?z
0 ? false : true; Ig}G"GR
} PElC0qCn[
Ni#!C:q
{e\Pd!D?|
} 'bJ!~ML&
_*7h1[,{f
rl4B(NZi}
7zXFQ|TP
bO 2>ced
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。 GmP)"@O](;
:i_818h!?[
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 4e~^G
u\wdb^8ds
做法如下: T]Z|Wq`bot
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 s:3 altv
#"-?+F=rk
的信息,和一个结果集List: l*>t@:2J
java代码: m^0r9y,
+KgoL a
;*1bTdB5a
/*Created on 2005-6-13*/ uPKq<hBI
package com.adt.bo; <_$]!Z6UR
?j;e/r.
import java.util.List; (MhC83|?
pd{W(M78g
import org.flyware.util.page.Page; K]ob>wPf
nwswy]e8/
/** +^ a9i5
* @author Joa bP\0S@1YL
*/ A'r 3%mC
publicclass Result { QA>(}u\+
qzS 9ls>>
private Page page; CF"$&+ s9
rCfr&>nn
private List content; <6QG7i
uMVM- (g%
/** %|E'cdvkX
* The default constructor _Z?{&k
*/ `q|&;wP.
public Result(){ mAMi-9
super(); **_`AM~
} D,q=?~
g?`g+:nug
/** t\~lGG-p
* The constructor using fields i)9}+M5
* ;, P-2\V/
* @param page arJ4^ d
* @param content :MeshzWK
*/ D FDC'E
public Result(Page page, List content){ 2gz}]_
this.page = page; kms&o=^
this.content = content; D^Ahw"X)
} ,K9\;{C
3D_Ky Z~M+
/** KilgeN:
* @return Returns the content. CvfXm
*/ zvjVM"=G
publicList getContent(){ 0q'd }D W
return content; L[l?}\
} uo0g51%9
,:g.B\'Q
/** $$ %4,\{l
* @return Returns the page. y_O [r1MF
*/ n,sf$9"
public Page getPage(){ "hwg";Z$n
return page; f!6oW( r-L
} =|>CB
Y<|!)JLB2
/** S\fEV"
* @param content 3sG7G:4
* The content to set.
aEUC
*/ Fe
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public void setContent(List content){ mr:;Wwd
this.content = content; Yhdt"@;..
} 1HQh%dZZ
?#8',:
/** r~cmrLQa
* @param page ,XT#V\qne
* The page to set. nk.Y#+1)
*/ [Du@go1C
publicvoid setPage(Page page){ Z$qFjWp
this.page = page; 3t<XbHF9
} U'^AJ2L8
} +5J "G/f
[h>|6%sW
<$\vL
s ^NO(
mF!/8qk
2. 编写业务逻辑接口,并实现它(UserManager, FTM(y CN
Jf\lnJTyU8
UserManagerImpl) hZGoiWC
java代码: f[,9WkC
vZV+24YWb
.G}E
/*Created on 2005-7-15*/ D|8vS8p
package com.adt.service; y,qP$5xiq
fR_
jYP1
import net.sf.hibernate.HibernateException; GwiG..Y]&
H I/]s^aL
import org.flyware.util.page.Page; 1I({2@C
G| 7\[!R
import com.adt.bo.Result; a<X8l^Ln
blxAy
/** W{E22J}
* @author Joa ,#3}TDC
*/ JFaxxW
publicinterface UserManager { gfE<XrG
2
q RXA
public Result listUser(Page page)throws [6x-c;H_4
0_yE74i
HibernateException; F#=XJYG1
t~pA2?9@
} {MmHR
`@GqD
>cwyb9;!kK
Z09FW>"u
K/RQ-xd4
java代码: H5t 9Mg|
J6x\_]1:*
216+ tX5Z
/*Created on 2005-7-15*/ M=[ /v/M=
package com.adt.service.impl; 2m.RM&TdB
H
<CsB
import java.util.List; @rs(`4QEh
ZJ(/cD
import net.sf.hibernate.HibernateException; v-6"*EP
?f v?6r
import org.flyware.util.page.Page; qGMM3a)Q
import org.flyware.util.page.PageUtil; ';`fMcN
Ke-Q>sm2Q
import com.adt.bo.Result; M0!;{1
import com.adt.dao.UserDAO; +3.Ik,Z}zq
import com.adt.exception.ObjectNotFoundException; N[4v6GS
import com.adt.service.UserManager; }HS:3Dt
?]gZg[
/** @C)O[&Sk
* @author Joa lhg3
}dW
*/ T!$7:% D
publicclass UserManagerImpl implements UserManager { zb9^ii$g
jB }O6u[%
private UserDAO userDAO; &d`T~fl|
0
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/** H"(:6
`
* @param userDAO The userDAO to set. MhC74G
*/
1?)iCe
publicvoid setUserDAO(UserDAO userDAO){ xw: v|(
this.userDAO = userDAO; >yvP[$]!6
} !mFo:nQ)}
f uojf+i
/* (non-Javadoc) ja$>>5<q
* @see com.adt.service.UserManager#listUser r`u}n
}_XW?^/8
(org.flyware.util.page.Page) sh.xp8^)^>
*/ :1u>T3L.z
public Result listUser(Page page)throws ga#,42)H
&_FNDJ>MCk
HibernateException, ObjectNotFoundException { ,2S
<#p!
int totalRecords = userDAO.getUserCount(); /2^cty.BXw
if(totalRecords == 0) hT6:7_UD
throw new ObjectNotFoundException *ggTTHy
>(z{1'f{
("userNotExist"); T#Pz_
hAu
page = PageUtil.createPage(page, totalRecords); 04tUf3>
List users = userDAO.getUserByPage(page); AIsM:sV]
returnnew Result(page, users); 2'g< H-[
} 6QdNGpN
O%v(~&OSl
} ^)N[x''a
nPq\J~M
~\dpD
>_M}l@1
\Ekez~k{`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Qu]0BVIe
z.16%@R
询,接下来编写UserDAO的代码:
H%7V)"
3. UserDAO 和 UserDAOImpl: )hk=wu6
java代码: RBx`<iBe
;a!o$y
[rqe;00]
/*Created on 2005-7-15*/ 7HPLD&WPt
package com.adt.dao; ,4j$kR
i=_leC)rl
import java.util.List; sb4)@/Q7j
%u }|4BXoh
import org.flyware.util.page.Page; 322W"qduTZ
Qv8#{y@U
import net.sf.hibernate.HibernateException; !mBsDn(J
X[k-J\
/** $N;!. 5lX3
* @author Joa Lhl)p P17
*/ a#H=dIj
publicinterface UserDAO extends BaseDAO { x$CpUy{6
oT
8
publicList getUserByName(String name)throws Td[w<m+p<P
..FUg"sSO
HibernateException; IZ')1
OdQ>h$ gZ
publicint getUserCount()throws HibernateException; o0 -e,F>u
XBhWj\`(T
publicList getUserByPage(Page page)throws J'9&dt
"W6nW
HibernateException; + WPi}
V.WfP*~NJ
} S "oUE_>
<6/XE@"
6uDA{[OH
f<SSg*A;
x+B~ t4A
java代码: X1<)B]y
Y'fI4
+lJuF/sS8m
/*Created on 2005-7-15*/ 37p0*%a":
package com.adt.dao.impl; #BS]wj2#
B0p>' O2
import java.util.List; SUD]Wl7G`r
?Z4&j'z<
import org.flyware.util.page.Page; };9dd3X
%W"\
import net.sf.hibernate.HibernateException; :Tuy]]k
import net.sf.hibernate.Query; gZM{]GQ
(m;P,*
import com.adt.dao.UserDAO; ! qrF=a
4NR,"l)
/** dMGu9k~u
* @author Joa 3\=8tg p
*/ ZfT%EPoZ:
public class UserDAOImpl extends BaseDAOHibernateImpl -Qnnzp$]
nWFp$tJ/R
implements UserDAO { ^'EEry
:^%soEi
/* (non-Javadoc) V EY !0PIj
* @see com.adt.dao.UserDAO#getUserByName @mP@~
/l(:H
(java.lang.String) q,nj|9z V
*/ gEKJrAA
publicList getUserByName(String name)throws "]c:V4S#`A
S-2xe?sb
HibernateException { ?Tuh22J{Q
String querySentence = "FROM user in class bDUGzezP<
s+zb[3}
com.adt.po.User WHERE user.name=:name"; $L</{bXW
Query query = getSession().createQuery {(a@3m~a%
3kR- WgVF,
(querySentence); ^ Jnp\o>
query.setParameter("name", name); hph 3kfR
return query.list(); Jq6p5jr"
} W[^XG\
Rp`}"x9
/* (non-Javadoc) l^$:R~gS
* @see com.adt.dao.UserDAO#getUserCount() PNc200`v4_
*/ vJ"@#$.
publicint getUserCount()throws HibernateException { !LIWoa[ F.
int count = 0; asQ" |]m
String querySentence = "SELECT count(*) FROM w-/bLg[L?$
s #L1:L
user in class com.adt.po.User"; :\80*[=;Z
Query query = getSession().createQuery yrsP'th
_9n.ir5YX
(querySentence); nWXI*%m5
count = ((Integer)query.iterate().next :Hd?0eZ|
CWBsiL
f
()).intValue(); Q]6nW[@j'
return count; ?'T>/<(
} $Fr2oSTT)
M8juab%y
/* (non-Javadoc) !Z=`Wk5
* @see com.adt.dao.UserDAO#getUserByPage g<,v2A
Eq.c;3
(org.flyware.util.page.Page) 1Za\T?V
*/ ?5B}ZMW
publicList getUserByPage(Page page)throws AO']Kmm
5 yA^ n6
HibernateException { #{h4lte
String querySentence = "FROM user in class 6Ir
?@O1'!
T$}<So|
com.adt.po.User"; 42m`7uQ
Query query = getSession().createQuery 8 6L&u:o:
*EV] 8
(querySentence); _^a.kF
query.setFirstResult(page.getBeginIndex()) m@zxjIwT
.setMaxResults(page.getEveryPage()); ^S<Z'S
return query.list(); 8kMMQ ES
} y|MW-|0=!
t4gD*j6J3
} sp_(j!]jX
7FMHz.ZRE
hJd#Gc~*M
up:e0di{
a[(n91J0
至此,一个完整的分页程序完成。前台的只需要调用 i( c2NPbX
m%Ef]({I
userManager.listUser(page)即可得到一个Page对象和结果集对象 2&tGJq-E
u|QfCwQ
的综合体,而传入的参数page对象则可以由前台传入,如果用 @F,HyCSN
,YkQJ$
webwork,甚至可以直接在配置文件中指定。 @L0wd>
t#P)KcWOt
下面给出一个webwork调用示例: HvTi^Fb\a
java代码: <M$hj6.tn
&0>{mq}p,:
e9%6+9Y
/*Created on 2005-6-17*/ %djx0sy
package com.adt.action.user; QGshc
Upv2s:wa}z
import java.util.List; C62<pLJf
_&dGo(B
import org.apache.commons.logging.Log; aB'<#X$x
import org.apache.commons.logging.LogFactory; sL\|y38'
import org.flyware.util.page.Page; pnqjATGU
;bAy7
import com.adt.bo.Result; I)Y$?"
import com.adt.service.UserService; |Zt=8}di
import com.opensymphony.xwork.Action; jM7}LV1Ck
+u)'
/** (yX Vp2k
* @author Joa f ~Fus
*/ ^)fB
"!s
publicclass ListUser implementsAction{ mB1)!
rBny*! n
privatestaticfinal Log logger = LogFactory.getLog BR0bf5T/
u@gYEx}
(ListUser.class); =vK (-h
T.(SBP
private UserService userService; xE)pj|
G4RsH/
private Page page; Ko%rB+d
qlgh$9
privateList users; Wc]Fg9E
~Snw':
/* ,U7hzBj8k
* (non-Javadoc) `nizGg~1
* mYy3KqYu
* @see com.opensymphony.xwork.Action#execute() d->b9
*/ :ZzG5[o3
publicString execute()throwsException{ O!j@8~='
Result result = userService.listUser(page); p[/n[@<8=
page = result.getPage(); XBr>K>(
users = result.getContent(); NKB!_R+
return SUCCESS; HFDg@@
} ]3I_H+hU
Jz|(B_U
/** xv%}xeEV
* @return Returns the page. RV($G8U
*/ o3W5FHFAv
public Page getPage(){ u#P7~9ZG-
return page; 'PO1{&M
} ~z'0~3
t6"4+:c!>
/** 'rF TtT
* @return Returns the users. -[7.VP
*/
"Km`B1f`
publicList getUsers(){ ?_^9e
return users; Fj&vWj`*
} UbYKiLDF)
Ec[:6}
/** WI6er;D
* @param page K{iayg!k
* The page to set. *1%g=vb
*/ pTN_6=Y"
publicvoid setPage(Page page){ zCQv:.0L
this.page = page; TxiJ?sDh*
} DBv5Og
es6e-y@e
/** pE`(kD
* @param users \UC4ai2MK
* The users to set. 1rKR=To
*/ gTq-\k(
publicvoid setUsers(List users){ +amvQ];?Q8
this.users = users; awawq9)Y
} *PI3L/*
^Uf`w7"iY
/** O7K))w
* @param userService
h!Q>h7
* The userService to set. [6Wr
t8"
*/ '0=U+Egp
publicvoid setUserService(UserService userService){ 4 '+)9&g
this.userService = userService; ~W#f,mf
} $K iMu
} 7]^Cg;EtM:
*\`C!r
jsG9{/Ov3
[:k'VXL
hh?'tb{
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ,S8Vfb &
ysa"f+/
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Rsulp#['
*H$nydQ:
么只需要: W`\H3?C`xQ
java代码: F;ZLoG*U
yjpjJ
G]S E
A
<?xml version="1.0"?> V4"AFArI
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork .dygp"*
4a 5n*6G!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- y,
Z#?O
::R^ w"
1.0.dtd"> a}
/Vu"
5FzRusNiA
<xwork> Cse0!7_T
\xdt|:8
<package name="user" extends="webwork- 3xe8DD
0g+@WK6y
interceptors"> Y!`?q8z$G
s%:fB(
<!-- The default interceptor stack name y>OZ<!`
MPB6
--> %,^7J;
<default-interceptor-ref <|8l ;
! $iR:ji
name="myDefaultWebStack"/> Y}Dp{
DYl^6]
<action name="listUser" _(jE](,
UqHO S{\Sz
class="com.adt.action.user.ListUser"> 08f~vw"
<param 1_t Dp&UO
i`Yf|^;@2>
name="page.everyPage">10</param> l=oVC6C
<result x
B?:G
7HJv4\K
name="success">/user/user_list.jsp</result> Y1~SGg7(@
</action> =j{jylC
`~}7k)F(
</package> zm:=d>D..
UVLcR
</xwork> !vB%Q$!x
5B2,=?+o
R',w~1RV'
zbR.Lb
"tark'
4Rm3'Ch
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 W>~%6K>p
7L]?)2=
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。 Gh
pd
k;
A)#sh)
}Q
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 2mO#vTX4
c>R(Fs|6
(w-u"1&
VB#31T#q?
g5Vr2
我写的一个用于分页的类,用了泛型了,hoho 2%8Y-o?
KCu6:)6'
java代码: >SJ$41"E
""+*Gn7^8
pd1m/:
package com.intokr.util; Psa8OJan
kziBHis!
import java.util.List; U{_s1
7`/qL "
/** CJOl|"UyJ
* 用于分页的类<br> ]aRD6F:L
* 可以用于传递查询的结果也可以用于传送查询的参数<br> qWpC e*C
* &V3oW1*W
* @version 0.01 ) T1oDk
* @author cheng *N r|G61
*/ >FHsZKJ
public class Paginator<E> { Fdw[CYHz
privateint count = 0; // 总记录数 ."X~?Nk
privateint p = 1; // 页编号 |BkY"F7m9
privateint num = 20; // 每页的记录数 #[W[|m
privateList<E> results = null; // 结果 !S!03|
@qDrTH]5
/** @,&m`qzd+
* 结果总数 @>@Nug2
*/ QL2y,?Mz7
publicint getCount(){ 3R*@m
return count; X-,y[ )
} LwPM7S~ *
/vDF<HVzm
publicvoid setCount(int count){ S7/v,E
this.count = count; \,!q[nC
} Q/n.T0Z^
I
6YT|R
/** Bqi2n'^O2
* 本结果所在的页码,从1开始
;"^9L
* .^S78hr]n
* @return Returns the pageNo. F\R}no5C
*/ cOZ^huK
publicint getP(){ y7-:l u$9
return p; J\ +gd%
} b6Hk20+B;
B9DxV>mr\r
/** ;cn.s,
* if(p<=0) p=1 GKhwn&qCKb
* \,gZNe&Vv
* @param p s~ZFVi-i
*/ .b`P!
publicvoid setP(int p){ +fQL~0tA
if(p <= 0) u^$Md WP
p = 1; i{ @'\}{L
this.p = p; +i#sS19h
} /7@2Qc2
8ysK VF
/** eJGos!>*
* 每页记录数量 VQ<i$ I
*/ TDE1z>h+"
publicint getNum(){ X&?lDL7?
return num; T\!SA
} _`{{39 F
5b`xN!c
/** 25c!-.5D
* if(num<1) num=1 2 `h!:0
*/ B;]5,`#!
publicvoid setNum(int num){ )UZ0gfx
if(num < 1) x5z4Yv^
m
num = 1; ZV]e-
this.num = num; ,(27p6!
} ~!-8l&C
>DUE8hp;<
/** nYy}''l<
* 获得总页数 KbdfSF$
*/ *-AAQ
publicint getPageNum(){ %
r Y8
return(count - 1) / num + 1; >^f)|0dn)E
} .S'fM]_#
]|t.wr3AU
/** ,e FQ}&^A
* 获得本页的开始编号,为 (p-1)*num+1 N%rL=zE
*/ FgQ_a/*
publicint getStart(){ fk7Cf"[w
return(p - 1) * num + 1; ,PMb9O\B
} B/D\gjb
<S8W~wC
/** #G+
* @return Returns the results. -Bo~"q
*/ TflS@Z7C
publicList<E> getResults(){ 9g
&Ch9-/
return results; BZ;}ROmqk
} Ym.l@(
B+e_Y\Bu
public void setResults(List<E> results){ tkN3BQ
this.results = results; NC.P2^%
} T$^>Fiz{Se
$#7J\=GZ+
public String toString(){ 4%fN\f
StringBuilder buff = new StringBuilder r d6F"W
Ls>u`hG
(); 8yWu{'G
buff.append("{"); 5\ w=(c9A
buff.append("count:").append(count); 8f,'p}@!d
buff.append(",p:").append(p); mo#0q&ZQ
buff.append(",nump:").append(num); HA9Nr.NqC@
buff.append(",results:").append =tc`:!$
|aS~"lImh
(results); Cj !i)-
buff.append("}"); <duBwkiG
return buff.toString(); ]opW; |{e
} {Bq"$M!Y
Oh/b?|imG
} :q>oD-b$}
MLt'YW^
U +*oI *