com.fitbur.bytebuddy.implementation.bytecode.constant.DoubleConstant Maven / Gradle / Ivy
package com.fitbur.bytebuddy.implementation.bytecode.constant;
import com.fitbur.bytebuddy.implementation.Implementation;
import com.fitbur.bytebuddy.implementation.bytecode.StackManipulation;
import com.fitbur.bytebuddy.implementation.bytecode.StackSize;
import com.fitbur.bytebuddy.jar.asm.MethodVisitor;
import com.fitbur.bytebuddy.jar.asm.Opcodes;
/**
* This class is responsible for loading any {@code double} constant onto the operand stack.
*/
public enum DoubleConstant implements StackManipulation {
/**
* A {@code double} constant of value {@code 0.0}.
*/
ZERO(Opcodes.DCONST_0),
/**
* A {@code double} constant of value {@code 1.0}.
*/
ONE(Opcodes.DCONST_1);
/**
* The size impact of loading a {@code double} constant onto the operand stack.
*/
private static final StackManipulation.Size SIZE = StackSize.DOUBLE.toIncreasingSize();
/**
* The shortcut opcode for loading a {@code double} constant.
*/
private final int opcode;
/**
* Creates a new shortcut operation for loading a common {@code double} onto the operand stack.
*
* @param opcode The shortcut opcode for loading a {@code double} constant.
*/
DoubleConstant(int opcode) {
this.opcode = opcode;
}
/**
* Creates a stack manipulation for loading a {@code double} value onto the operand stack.
*
* This is achieved either by invoking a specific opcode, if any, or by creating a constant pool entry.
*
* @param value The {@code double} value to load onto the stack.
* @return A stack manipulation for loading the given {@code double} value.
*/
public static StackManipulation forValue(double value) {
if (value == 0d) {
return ZERO;
} else if (value == 1d) {
return ONE;
} else {
return new ConstantPool(value);
}
}
@Override
public boolean isValid() {
return true;
}
@Override
public StackManipulation.Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
methodVisitor.visitInsn(opcode);
return SIZE;
}
@Override
public String toString() {
return "DoubleConstant." + name();
}
/**
* A stack manipulation for loading a {@code double} value from a class's constant pool onto the operand stack.
*/
protected static class ConstantPool implements StackManipulation {
/**
* The {@code double} value to be loaded onto the operand stack.
*/
private final double value;
/**
* Creates a new constant pool load operation.
*
* @param value The {@code double} value to be loaded onto the operand stack.
*/
protected ConstantPool(double value) {
this.value = value;
}
@Override
public boolean isValid() {
return true;
}
@Override
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
methodVisitor.visitLdcInsn(value);
return SIZE;
}
@Override
public boolean equals(Object other) {
return this == other || !(other == null || getClass() != other.getClass())
&& Double.compare(((ConstantPool) other).value, value) == 0;
}
@Override
public int hashCode() {
long temp = Double.doubleToLongBits(value);
return (int) (temp ^ (temp >>> 32));
}
@Override
public String toString() {
return "DoubleConstant.ConstantPool{value=" + value + '}';
}
}
}