eclipse 設定java虛擬機器記憶體大小

100W資料，堆記憶體不夠用
生成關聯規則需要資料的開始時間，2011-02-17 09:16:48
log4j:WARN No appenders could be found for logger (org.springframework.context.support.ClassPathXmlApplicationContext).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
 at java.lang.reflect.Method.copy(Method.java:143)
 at java.lang.reflect.ReflectAccess.copyMethod(ReflectAccess.java:118)
 at sun.reflect.ReflectionFactory.copyMethod(ReflectionFactory.java:282)
 at java.lang.Class.copyMethods(Class.java:2748)
 at java.lang.Class.getDeclaredMethods(Class.java:1791)
 at java.beans.Introspector$1.run(Introspector.java:1272)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1270)
 at java.beans.Introspector.internalFindMethod(Introspector.java:1306)
 at java.beans.Introspector.findMethod(Introspector.java:1377)
 at java.beans.PropertyDescriptor.getWriteMethod(PropertyDescriptor.java:246)
 at org.apache.commons.dbutils.BeanProcessor.callSetter(BeanProcessor.java:227)
 at org.apache.commons.dbutils.BeanProcessor.createBean(BeanProcessor.java:210)
 at org.apache.commons.dbutils.BeanProcessor.toBean(BeanProcessor.java:125)
 at org.apache.commons.dbutils.BasicRowProcessor.toBean(BasicRowProcessor.java:111)
 at org.apache.commons.dbutils.handlers.BeanListHandler.handleRow(BeanListHandler.java:77)
 at org.apache.commons.dbutils.handlers.GenericListHandler.handle(GenericListHandler.java:43)
 at org.apache.commons.dbutils.QueryRunner.query(QueryRunner.java:237)
 at com.xxt.dbutils.QueryUtil.query(QueryUtil.java:276)
 at com.xxt.dbutils.QueryUtil.query(QueryUtil.java:254)
 at cn.xxt.clickstream.dao.XxtWebLogDAO.getAllClickInfo(XxtWebLogDAO.java:37)
 at cn.xxt.clickstream.service.AssociationRuleData.getAllClickInfo(AssociationRuleData.java:167)
 at cn.xxt.clickstream.service.AssociationRuleData.main(AssociationRuleData.java:45)

開啟eclipse,選擇Window--Preferences...在對話方塊左邊的樹上雙擊Java，再雙擊Installed JREs，在右邊選擇前面有對勾的JRE，再單擊右邊的“Edit”按鈕，
出現一個 Edit JRE 的對話方塊，在其中的Default VM Arguments: 框中輸入 -Xms128m -Xmx512m ,這樣設定Java擬虛機記憶體使用最小是128M，最大是512M，再單擊“OK”關閉 Edit JRE 對話方塊，再單擊“OK”關閉 Preferences對話方塊，Eclipse一下子就執行快了起來