blob: e24ece18d256089aa9247471317f42d9b254348d [file] [log] [blame]
/*
* ProGuard -- shrinking, optimization, obfuscation, and preverification
* of Java bytecode.
*
* Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu)
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package proguard.evaluation.value;
/**
* This abstract class represents a partially evaluated value.
*
* @author Eric Lafortune
*/
public abstract class Value
{
public static final int NEVER = -1;
public static final int MAYBE = 0;
public static final int ALWAYS = 1;
public static final int TYPE_INTEGER = 1;
public static final int TYPE_LONG = 2;
public static final int TYPE_FLOAT = 3;
public static final int TYPE_DOUBLE = 4;
public static final int TYPE_REFERENCE = 5;
public static final int TYPE_INSTRUCTION_OFFSET = 6;
public static final int TYPE_TOP = 7;
/**
* Returns this Value as a Category1Value.
*/
public Category1Value category1Value()
{
throw new IllegalArgumentException("Value is not a Category 1 value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as a Category2Value.
*/
public Category2Value category2Value()
{
throw new IllegalArgumentException("Value is not a Category 2 value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as an IntegerValue.
*/
public IntegerValue integerValue()
{
throw new IllegalArgumentException("Value is not an integer value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as a LongValue.
*/
public LongValue longValue()
{
throw new IllegalArgumentException("Value is not a long value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as a FloatValue.
*/
public FloatValue floatValue()
{
throw new IllegalArgumentException("Value is not a float value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as a DoubleValue.
*/
public DoubleValue doubleValue()
{
throw new IllegalArgumentException("Value is not a double value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as a ReferenceValue.
*/
public ReferenceValue referenceValue()
{
throw new IllegalArgumentException("Value is not a reference value [" + this.getClass().getName() + "]");
}
/**
* Returns this Value as an InstructionOffsetValue.
*/
public InstructionOffsetValue instructionOffsetValue()
{
throw new IllegalArgumentException("Value is not an instruction offset value [" + this.getClass().getName() + "]");
}
/**
* Returns whether this Value represents a single specific (but possibly
* unknown) value.
*/
public boolean isSpecific()
{
return false;
}
/**
* Returns whether this Value represents a single particular (known)
* value.
*/
public boolean isParticular()
{
return false;
}
/**
* Returns the generalization of this Value and the given other Value.
*/
public abstract Value generalize(Value other);
/**
* Returns whether the computational type of this Value is a category 2 type.
* This means that it takes up the space of two category 1 types on the
* stack, for instance.
*/
public abstract boolean isCategory2();
/**
* Returns the computational type of this Value.
* @return <code>TYPE_INTEGER</code>,
* <code>TYPE_LONG</code>,
* <code>TYPE_FLOAT</code>,
* <code>TYPE_DOUBLE</code>,
* <code>TYPE_REFERENCE</code>, or
* <code>TYPE_INSTRUCTION_OFFSET</code>.
*/
public abstract int computationalType();
/**
* Returns the internal type of this Value.
* @return <code>ClassConstants.INTERNAL_TYPE_BOOLEAN</code>,
* <code>ClassConstants.INTERNAL_TYPE_BYTE</code>,
* <code>ClassConstants.INTERNAL_TYPE_CHAR</code>,
* <code>ClassConstants.INTERNAL_TYPE_SHORT</code>,
* <code>ClassConstants.INTERNAL_TYPE_INT</code>,
* <code>ClassConstants.INTERNAL_TYPE_LONG</code>,
* <code>ClassConstants.INTERNAL_TYPE_FLOAT</code>,
* <code>ClassConstants.INTERNAL_TYPE_DOUBLE</code>,
* <code>ClassConstants.INTERNAL_TYPE_CLASS_START ... ClassConstants.INTERNAL_TYPE_CLASS_END</code>, or
* an array type containing any of these types (always as String).
*/
public abstract String internalType();
}