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	/*
	* Copyright (c) 1998, 2011, 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.
	*/

	/*
	* This source code is provided to illustrate the usage of a given feature
	* or technique and has been deliberately simplified. Additional steps
	* required for a production-quality application, such as security checks,
	* input validation and proper error handling, might not be present in
	* this sample code.
	*/


	package com.sun.tools.example.debug.tty;

	import com.sun.jdi.*;
	import com.sun.jdi.request.*;

	import java.util.ArrayList;
	import java.util.List;

	class BreakpointSpec extends EventRequestSpec {
	String methodId;
	List<String> methodArgs;
	int lineNumber;

	BreakpointSpec(ReferenceTypeSpec refSpec, int lineNumber) {
	super(refSpec);
	this.methodId = null;
	this.methodArgs = null;
	this.lineNumber = lineNumber;
	}

	BreakpointSpec(ReferenceTypeSpec refSpec, String methodId,
	List<String> methodArgs) throws MalformedMemberNameException {
	super(refSpec);
	this.methodId = methodId;
	this.methodArgs = methodArgs;
	this.lineNumber = 0;
	if (!isValidMethodName(methodId)) {
	throw new MalformedMemberNameException(methodId);
	}
	}

	/**
	* The 'refType' is known to match, return the EventRequest.
	*/
	@Override
	EventRequest resolveEventRequest(ReferenceType refType)
	throws AmbiguousMethodException,
	AbsentInformationException,
	InvalidTypeException,
	NoSuchMethodException,
	LineNotFoundException {
	Location location = location(refType);
	if (location == null) {
	throw new InvalidTypeException();
	}
	EventRequestManager em = refType.virtualMachine().eventRequestManager();
	EventRequest bp = em.createBreakpointRequest(location);
	bp.setSuspendPolicy(suspendPolicy);
	bp.enable();
	return bp;
	}

	String methodName() {
	return methodId;
	}

	int lineNumber() {
	return lineNumber;
	}

	List<String> methodArgs() {
	return methodArgs;
	}

	boolean isMethodBreakpoint() {
	return (methodId != null);
	}

	@Override
	public int hashCode() {
	return refSpec.hashCode() + lineNumber +
	((methodId != null) ? methodId.hashCode() : 0) +
	((methodArgs != null) ? methodArgs.hashCode() : 0);
	}

	@Override
	public boolean equals(Object obj) {
	if (obj instanceof BreakpointSpec) {
	BreakpointSpec breakpoint = (BreakpointSpec)obj;

	return ((methodId != null) ?
	methodId.equals(breakpoint.methodId)
	: methodId == breakpoint.methodId) &&
	((methodArgs != null) ?
	methodArgs.equals(breakpoint.methodArgs)
	: methodArgs == breakpoint.methodArgs) &&
	refSpec.equals(breakpoint.refSpec) &&
	(lineNumber == breakpoint.lineNumber);
	} else {
	return false;
	}
	}

	@Override
	String errorMessageFor(Exception e) {
	if (e instanceof AmbiguousMethodException) {
	return (MessageOutput.format("Method is overloaded; specify arguments",
	methodName()));
	/*
	* TO DO: list the methods here
	*/
	} else if (e instanceof NoSuchMethodException) {
	return (MessageOutput.format("No method in",
	new Object [] {methodName(),
	refSpec.toString()}));
	} else if (e instanceof AbsentInformationException) {
	return (MessageOutput.format("No linenumber information for",
	refSpec.toString()));
	} else if (e instanceof LineNotFoundException) {
	return (MessageOutput.format("No code at line",
	new Object [] {new Long (lineNumber()),
	refSpec.toString()}));
	} else if (e instanceof InvalidTypeException) {
	return (MessageOutput.format("Breakpoints can be located only in classes.",
	refSpec.toString()));
	} else {
	return super.errorMessageFor( e);
	}
	}

	@Override
	public String toString() {
	StringBuffer buffer = new StringBuffer(refSpec.toString());
	if (isMethodBreakpoint()) {
	buffer.append('.');
	buffer.append(methodId);
	if (methodArgs != null) {
	boolean first = true;
	buffer.append('(');
	for (String arg : methodArgs) {
	if (!first) {
	buffer.append(',');
	}
	buffer.append(arg);
	first = false;
	}
	buffer.append(")");
	}
	} else {
	buffer.append(':');
	buffer.append(lineNumber);
	}
	return MessageOutput.format("breakpoint", buffer.toString());
	}

	private Location location(ReferenceType refType) throws
	AmbiguousMethodException,
	AbsentInformationException,
	NoSuchMethodException,
	LineNotFoundException {
	Location location = null;
	if (isMethodBreakpoint()) {
	Method method = findMatchingMethod(refType);
	location = method.location();
	} else {
	// let AbsentInformationException be thrown
	List<Location> locs = refType.locationsOfLine(lineNumber());
	if (locs.size() == 0) {
	throw new LineNotFoundException();
	}
	// TO DO: handle multiple locations
	location = locs.get(0);
	if (location.method() == null) {
	throw new LineNotFoundException();
	}
	}
	return location;
	}

	private boolean isValidMethodName(String s) {
	return isJavaIdentifier(s) \|\|
	s.equals("<init>") \|\|
	s.equals("<clinit>");
	}

	/*
	* Compare a method's argument types with a Vector of type names.
	* Return true if each argument type has a name identical to the
	* corresponding string in the vector (allowing for varars)
	* and if the number of arguments in the method matches the
	* number of names passed
	*/
	private boolean compareArgTypes(Method method, List<String> nameList) {
	List<String> argTypeNames = method.argumentTypeNames();

	// If argument counts differ, we can stop here
	if (argTypeNames.size() != nameList.size()) {
	return false;
	}

	// Compare each argument type's name
	int nTypes = argTypeNames.size();
	for (int i = 0; i < nTypes; ++i) {
	String comp1 = argTypeNames.get(i);
	String comp2 = nameList.get(i);
	if (! comp1.equals(comp2)) {
	/*
	* We have to handle varargs. EG, the
	* method's last arg type is xxx[]
	* while the nameList contains xxx...
	* Note that the nameList can also contain
	* xxx[] in which case we don't get here.
	*/
	if (i != nTypes - 1 \|\|
	!method.isVarArgs() \|\|
	!comp2.endsWith("...")) {
	return false;
	}
	/*
	* The last types differ, it is a varargs
	* method and the nameList item is varargs.
	* We just have to compare the type names, eg,
	* make sure we don't have xxx[] for the method
	* arg type and yyy... for the nameList item.
	*/
	int comp1Length = comp1.length();
	if (comp1Length + 1 != comp2.length()) {
	// The type names are different lengths
	return false;
	}
	// We know the two type names are the same length
	if (!comp1.regionMatches(0, comp2, 0, comp1Length - 2)) {
	return false;
	}
	// We do have xxx[] and xxx... as the last param type
	return true;
	}
	}

	return true;
	}


	/*
	* Remove unneeded spaces and expand class names to fully
	* qualified names, if necessary and possible.
	*/
	private String normalizeArgTypeName(String name) {
	/*
	* Separate the type name from any array modifiers,
	* stripping whitespace after the name ends
	*/
	int i = 0;
	StringBuffer typePart = new StringBuffer();
	StringBuffer arrayPart = new StringBuffer();
	name = name.trim();
	int nameLength = name.length();
	/*
	* For varargs, there can be spaces before the ... but not
	* within the ... So, we will just ignore the ...
	* while stripping blanks.
	*/
	boolean isVarArgs = name.endsWith("...");
	if (isVarArgs) {
	nameLength -= 3;
	}
	while (i < nameLength) {
	char c = name.charAt(i);
	if (Character.isWhitespace(c) \|\| c == '[') {
	break; // name is complete
	}
	typePart.append(c);
	i++;
	}
	while (i < nameLength) {
	char c = name.charAt(i);
	if ( (c == '[') \|\| (c == ']')) {
	arrayPart.append(c);
	} else if (!Character.isWhitespace(c)) {
	throw new IllegalArgumentException
	(MessageOutput.format("Invalid argument type name"));
	}
	i++;
	}
	name = typePart.toString();

	/*
	* When there's no sign of a package name already, try to expand the
	* the name to a fully qualified class name
	*/
	if ((name.indexOf('.') == -1) \|\| name.startsWith("*.")) {
	try {
	ReferenceType argClass = Env.getReferenceTypeFromToken(name);
	if (argClass != null) {
	name = argClass.name();
	}
	} catch (IllegalArgumentException e) {
	// We'll try the name as is
	}
	}
	name += arrayPart.toString();
	if (isVarArgs) {
	name += "...";
	}
	return name;
	}

	/*
	* Attempt an unambiguous match of the method name and
	* argument specification to a method. If no arguments
	* are specified, the method must not be overloaded.
	* Otherwise, the argument types much match exactly
	*/
	private Method findMatchingMethod(ReferenceType refType)
	throws AmbiguousMethodException,
	NoSuchMethodException {

	// Normalize the argument string once before looping below.
	List<String> argTypeNames = null;
	if (methodArgs() != null) {
	argTypeNames = new ArrayList<String>(methodArgs().size());
	for (String name : methodArgs()) {
	name = normalizeArgTypeName(name);
	argTypeNames.add(name);
	}
	}

	// Check each method in the class for matches
	Method firstMatch = null; // first method with matching name
	Method exactMatch = null; // (only) method with same name & sig
	int matchCount = 0; // > 1 implies overload
	for (Method candidate : refType.methods()) {
	if (candidate.name().equals(methodName())) {
	matchCount++;

	// Remember the first match in case it is the only one
	if (matchCount == 1) {
	firstMatch = candidate;
	}

	// If argument types were specified, check against candidate
	if ((argTypeNames != null)
	&& compareArgTypes(candidate, argTypeNames) == true) {
	exactMatch = candidate;
	break;
	}
	}
	}

	// Determine method for breakpoint
	Method method = null;
	if (exactMatch != null) {
	// Name and signature match
	method = exactMatch;
	} else if ((argTypeNames == null) && (matchCount > 0)) {
	// At least one name matched and no arg types were specified
	if (matchCount == 1) {
	method = firstMatch; // Only one match; safe to use it
	} else {
	throw new AmbiguousMethodException();
	}
	} else {
	throw new NoSuchMethodException(methodName());
	}
	return method;
	}
	}

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