| /* |
| * Copyright (c) 1998, 2013, 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 com.sun.jdi; |
| |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * The state of one method invocation on a thread's call stack. |
| * As a thread executes, stack frames are pushed and popped from |
| * its call stack as methods are invoked and then return. A StackFrame |
| * mirrors one such frame from a target VM at some point in its |
| * thread's execution. The call stack is, then, simply a List of |
| * StackFrame objects. The call stack can be obtained any time a thread |
| * is suspended through a call to {@link ThreadReference#frames} |
| * <p> |
| * StackFrames provide access to a method's local variables and their |
| * current values. |
| * <p> |
| * The lifetime of a StackFrame is very limited. It is available only |
| * for suspended threads and becomes invalid once its thread is resumed. |
| * <p> |
| * Any method on <code>StackFrame</code> which |
| * takes <code>StackFrame</code> as an parameter may throw |
| * {@link com.sun.jdi.VMDisconnectedException} if the target VM is |
| * disconnected and the {@link com.sun.jdi.event.VMDisconnectEvent} has been or is |
| * available to be read from the {@link com.sun.jdi.event.EventQueue}. |
| * <p> |
| * Any method on <code>StackFrame</code> which |
| * takes <code>StackFrame</code> as an parameter may throw |
| * {@link com.sun.jdi.VMOutOfMemoryException} if the target VM has run out of memory. |
| * |
| * @author Robert Field |
| * @author Gordon Hirsch |
| * @author James McIlree |
| * @since 1.3 |
| */ |
| @jdk.Exported |
| public interface StackFrame extends Mirror, Locatable { |
| |
| /** |
| * Returns the {@link Location} of the current instruction in the frame. |
| * The method for which this frame was created can also be accessed |
| * through the returned location. |
| * For the top frame in the stack, this location identifies the |
| * next instruction to be executed. For all other frames, this |
| * location identifies the instruction that caused the next frame's |
| * method to be invoked. |
| * If the frame represents a native method invocation, the returned |
| * location indicates the class and method, but the code index will |
| * not be valid (-1). |
| * |
| * @return the {@link Location} of the current instruction. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| */ |
| Location location(); |
| |
| /** |
| * Returns the thread under which this frame's method is running. |
| * |
| * @return a {@link ThreadReference} which mirrors the frame's thread. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| */ |
| ThreadReference thread(); |
| |
| /** |
| * Returns the value of 'this' for the current frame. |
| * The {@link ObjectReference} for 'this' is only available for |
| * non-native instance methods. |
| * |
| * @return an {@link ObjectReference}, or null if the frame represents |
| * a native or static method. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| */ |
| ObjectReference thisObject(); |
| |
| /** |
| * Returns a list containing each {@link LocalVariable} |
| * that can be accessed from this frame's location. |
| * <p> |
| * Visibility is based on the code index of the current instruction of |
| * this StackFrame. Each variable has a range of byte code indices in which |
| * it is accessible. |
| * If this stack frame's method |
| * matches this variable's method and if the code index of this |
| * StackFrame is within the variable's byte code range, the variable is |
| * visible. |
| * <p> |
| * A variable's byte code range is at least as large as the scope of |
| * that variable, but can continue beyond the end of the scope under |
| * certain circumstances: |
| * <ul> |
| * <li>the compiler/VM does not immediately reuse the variable's slot. |
| * <li>the compiler/VM is implemented to report the extended range that |
| * would result from the item above. |
| * </ul> |
| * The advantage of an extended range is that variables from recently |
| * exited scopes may remain available for examination (this is especially |
| * useful for loop indices). If, as a result of the extensions above, |
| * the current frame location is contained within the range |
| * of multiple local variables of the same name, the variable with the |
| * highest-starting range is chosen for the returned list. |
| * |
| * @return the list of {@link LocalVariable} objects currently visible; |
| * the list will be empty if there are no visible variables; |
| * specifically, frames in native methods will always return a |
| * zero-length list. |
| * @throws AbsentInformationException if there is no local variable |
| * information for this method. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| * @throws NativeMethodException if the current method is native. |
| */ |
| List<LocalVariable> visibleVariables() throws AbsentInformationException; |
| |
| /** |
| * Finds a {@link LocalVariable} that matches the given name and is |
| * visible at the current frame location. |
| * See {@link #visibleVariables} for more information on visibility. |
| * |
| * @param name the variable name to find |
| * @return the matching {@link LocalVariable}, or null if there is no |
| * visible variable with the given name; frames in native methods |
| * will always return null. |
| * @throws AbsentInformationException if there is no local variable |
| * information for this method. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| * @throws NativeMethodException if the current method is native. |
| */ |
| LocalVariable visibleVariableByName(String name) throws AbsentInformationException; |
| |
| /** |
| * Gets the {@link Value} of a {@link LocalVariable} in this frame. |
| * The variable must be valid for this frame's method and visible |
| * according to the rules described in {@link #visibleVariables}. |
| * |
| * @param variable the {@link LocalVariable} to be accessed |
| * @return the {@link Value} of the instance field. |
| * @throws java.lang.IllegalArgumentException if the variable is |
| * either invalid for this frame's method or not visible. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| */ |
| Value getValue(LocalVariable variable); |
| |
| /** |
| * Returns the values of multiple local variables in this frame. |
| * Each variable must be valid for this frame's method and visible |
| * according to the rules described in {@link #visibleVariables}. |
| * |
| * @param variables a list of {@link LocalVariable} objects to be accessed |
| * @return a map associating each {@link LocalVariable} with |
| * its {@link Value} |
| * @throws java.lang.IllegalArgumentException if any variable is |
| * either invalid for this frame's method or not visible. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| */ |
| Map<LocalVariable,Value> getValues(List<? extends LocalVariable> variables); |
| |
| /** |
| * Sets the {@link Value} of a {@link LocalVariable} in this frame. |
| * The variable must be valid for this frame's method and visible |
| * according to the rules described in {@link #visibleVariables}. |
| * <p> |
| * Object values must be assignment compatible with the variable type |
| * (This implies that the variable type must be loaded through the |
| * enclosing class's class loader). Primitive values must be |
| * either assignment compatible with the variable type or must be |
| * convertible to the variable type without loss of information. |
| * See JLS section 5.2 for more information on assignment |
| * compatibility. |
| * |
| * @param variable the field containing the requested value |
| * @param value the new value to assign |
| * @throws java.lang.IllegalArgumentException if the field is not valid for |
| * this object's class. |
| * @throws InvalidTypeException if the value's type does not match |
| * the variable's type. |
| * @throws ClassNotLoadedException if the variable type has not yet been loaded |
| * through the appropriate class loader. |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| * @throws VMCannotBeModifiedException if the VirtualMachine is read-only - see {@link VirtualMachine#canBeModified()}. |
| */ |
| void setValue(LocalVariable variable, Value value) |
| throws InvalidTypeException, ClassNotLoadedException; |
| |
| /** |
| * Returns the values of all arguments in this frame. Values are |
| * returned even if no local variable information is present. |
| * |
| * @return a list containing a {@link Value} object for each argument |
| * to this frame, in the order in which the arguments were |
| * declared. If the method corresponding to this frame has |
| * no arguments, an empty list is returned. |
| * |
| * @throws InvalidStackFrameException if this stack frame has become |
| * invalid. Once the frame's thread is resumed, the stack frame is |
| * no longer valid. |
| * @since 1.6 |
| */ |
| List<Value> getArgumentValues(); |
| |
| } |
