com.holmos.cache.size.layout.ClassSizeInfoParser Maven / Gradle / Ivy
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package com.holmos.cache.size.layout;
import com.holmos.cache.size.layout.impl.Hotspot32MemoryLayoutSpecification;
import com.holmos.cache.size.layout.impl.Hotspot64MemoryLayoutSpecification;
/**
* 类的占用内存信息的获取器
*
* @author 吴银龙([email protected])
* */
public class ClassSizeInfoParser {
private static MemoryLayoutSpecification memoryLayoutSpecification;
public static MemoryLayoutSpecification getLayoutSpecification(){
return memoryLayoutSpecification;
}
static{
final String vmName = System.getProperty("java.vm.name");
if (vmName == null || !vmName.startsWith("Java HotSpot(TM) ")) {
throw new UnsupportedOperationException(
"ObjectSizeCalculator only supported on HotSpot VM");
}
final String dataModel = System.getProperty("sun.arch.data.model");
if ("32".equals(dataModel)) {
memoryLayoutSpecification= new Hotspot32MemoryLayoutSpecification();
}else if("64".equals(dataModel)){
memoryLayoutSpecification=new Hotspot64MemoryLayoutSpecification();
}
}
public static int getPrimitiveType(Class type){
if(long.class == type || double.class == type)
return 3;
else if(int.class == type || float.class == type)
return 2;
else if(char.class == type || short.class == type)
return 1;
else if(boolean.class == type || byte.class == type)
return 0;
else
return 4;
}
}