/* * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.lang; import java.lang.StackWalker.StackFrame; import java.util.EnumSet; import java.util.Set; import static java.lang.StackWalker.ExtendedOption.LOCALS_AND_OPERANDS; /** * UNSUPPORTED This interface is intended to be package-private * or move to an internal package.
* * {@code LiveStackFrame} represents a frame storing data and partial results. * Each frame has its own array of local variables (JVMS section 2.6.1), * its own operand stack (JVMS section 2.6.2) for a method invocation. * * @jvms 2.6 Frames */ /* package-private */ interface LiveStackFrame extends StackFrame { /** * Return the monitors held by this stack frame. This method returns * an empty array if no monitor is held by this stack frame. * * @return the monitors held by this stack frames */ public Object[] getMonitors(); /** * Gets the local variable array of this stack frame. * *
A single local variable can hold a value of type boolean, byte, char, * short, int, float, reference or returnAddress. A pair of local variables * can hold a value of type long or double. In other words, * a value of type long or type double occupies two consecutive local * variables. For a value of primitive type, the element in the * local variable array is an {@link PrimitiveValue} object; * otherwise, the element is an {@code Object}. * * @return the local variable array of this stack frame. */ public Object[] getLocals(); /** * Gets the operand stack of this stack frame. * *
* The 0-th element of the returned array represents the top of the operand stack. * This method returns an empty array if the operand stack is empty. * *
Each entry on the operand stack can hold a value of any Java Virtual * Machine Type. * For a value of primitive type, the element in the returned array is * an {@link PrimitiveValue} object; otherwise, the element is the {@code Object} * on the operand stack. * * @return the operand stack of this stack frame. */ public Object[] getStack(); /** * UNSUPPORTED This interface is intended to be package-private * or move to an internal package.
*
* Represents a local variable or an entry on the operand whose value is
* of primitive type.
*/
public abstract class PrimitiveValue {
/**
* Returns the base type of this primitive value, one of
* {@code B, D, C, F, I, J, S, Z}.
*
* @return Name of a base type
* @jvms table 4.3-A
*/
abstract char type();
/**
* Returns the boolean value if this primitive value is of type boolean.
* @return the boolean value if this primitive value is of type boolean.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type boolean.
*/
public boolean booleanValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the int value if this primitive value is of type int.
* @return the int value if this primitive value is of type int.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type int.
*/
public int intValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the long value if this primitive value is of type long.
* @return the long value if this primitive value is of type long.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type long.
*/
public long longValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the char value if this primitive value is of type char.
* @return the char value if this primitive value is of type char.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type char.
*/
public char charValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the byte value if this primitive value is of type byte.
* @return the byte value if this primitive value is of type byte.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type byte.
*/
public byte byteValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the short value if this primitive value is of type short.
* @return the short value if this primitive value is of type short.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type short.
*/
public short shortValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the float value if this primitive value is of type float.
* @return the float value if this primitive value is of type float.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type float.
*/
public float floatValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
/**
* Returns the double value if this primitive value is of type double.
* @return the double value if this primitive value is of type double.
*
* @throws UnsupportedOperationException if this primitive value is not
* of type double.
*/
public double doubleValue() {
throw new UnsupportedOperationException("this primitive of type " + type());
}
}
/**
* Gets {@code StackWalker} that can get locals and operands.
*
* @throws SecurityException if the security manager is present and
* denies access to {@code RuntimePermission("liveStackFrames")}
*/
public static StackWalker getStackWalker() {
return getStackWalker(EnumSet.noneOf(StackWalker.Option.class));
}
/**
* Gets a {@code StackWalker} instance with the given options specifying
* the stack frame information it can access, and which will traverse at most
* the given {@code maxDepth} number of stack frames. If no option is
* specified, this {@code StackWalker} obtains the method name and
* the class name with all
* {@linkplain StackWalker.Option#SHOW_HIDDEN_FRAMES hidden frames} skipped.
* The returned {@code StackWalker} can get locals and operands.
*
* @param options stack walk {@link StackWalker.Option options}
*
* @throws SecurityException if the security manager is present and
* it denies access to {@code RuntimePermission("liveStackFrames")}; or
* or if the given {@code options} contains
* {@link StackWalker.Option#RETAIN_CLASS_REFERENCE Option.RETAIN_CLASS_REFERENCE}
* and it denies access to {@code StackFramePermission("retainClassReference")}.
*/
public static StackWalker getStackWalker(Set