com.phloc.commons.system.EProcessorArchitecture Maven / Gradle / Ivy
/**
* Copyright (C) 2006-2015 phloc systems
* http://www.phloc.com
* office[at]phloc[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.phloc.commons.system;
import javax.annotation.Nonnull;
import com.phloc.commons.CGlobal;
import com.phloc.commons.SystemProperties;
import com.phloc.commons.string.StringParser;
/**
* Enum for representing the current processor architecture. Works only on Sun
* JVMs using the proprietary system property sun.arch.data.model.
*
* @author Philip Helger
*/
public enum EProcessorArchitecture
{
/** Unknown architecture - could not be determined. */
UNKNOWN (CGlobal.ILLEGAL_UINT),
/** 32 bit architecture. */
ARCH_32 (32),
/** 64 bit architecture. */
ARCH_64 (64);
private static final String SUN_SYSTEM_PROPERTY = "sun.arch.data.model";
/** The current architecture. */
private static volatile EProcessorArchitecture s_aInstance = null;
private final int m_nBits;
private EProcessorArchitecture (final int nBits)
{
if (nBits > 0 && (nBits % CGlobal.BITS_PER_BYTE) != 0)
throw new IllegalArgumentException ("Passed bit count is illegal: " + nBits);
m_nBits = nBits;
}
/**
* @return The number of bits of this architecture. May be
* {@link CGlobal#ILLEGAL_UINT} for the unknown architecture.
*/
public int getBits ()
{
return m_nBits;
}
/**
* @return The number of bytes of this architecture (=bits/8). May be
* {@link CGlobal#ILLEGAL_UINT} for the unknown architecture.
*/
public int getBytes ()
{
return m_nBits == CGlobal.ILLEGAL_UINT ? m_nBits : m_nBits / CGlobal.BITS_PER_BYTE;
}
/**
* @return The number of bits in the current architecture or
* {@link CGlobal#ILLEGAL_UINT} if this is undetermined.
*/
public static int getCurrentArchitectureBits ()
{
return StringParser.parseInt (SystemProperties.getPropertyValue (SUN_SYSTEM_PROPERTY), CGlobal.ILLEGAL_UINT);
}
/**
* Get the processor architecture based on the passed number of bits.
*
* @param nBits
* The number of bits to get the processor architecture from.
* @return {@link #UNKNOWN} if no processor architecture could be determined.
*/
@Nonnull
public static EProcessorArchitecture forBits (final int nBits)
{
for (final EProcessorArchitecture eArch : values ())
if (nBits == eArch.getBits ())
return eArch;
return UNKNOWN;
}
/**
* @return The current processor architecture if running inside a Sun JVM. If
* no processor architecture could be determined, {@link #UNKNOWN} is
* returned and never null.
*/
@Nonnull
static EProcessorArchitecture getCurrentArchitecture ()
{
EProcessorArchitecture ret = s_aInstance;
if (ret == null)
{
// Note: double initialization doesn't matter here
ret = forBits (getCurrentArchitectureBits ());
s_aInstance = ret;
}
return ret;
}
}