From 4b393cf44814391705506e32ea3e7dc398d0ebb5 Mon Sep 17 00:00:00 2001
From: parrt <parrt@antlr.org>
Date: Tue, 22 Nov 2011 14:33:35 -0800
Subject: [PATCH] rm QStack and use ArrayDeque

[git-p4: depot-paths = "//depot/code/antlr4/main/": change = 9427]
---
 .../Java/src/org/antlr/v4/runtime/Lexer.java  |  6 +-
 .../src/org/antlr/v4/runtime/misc/QStack.java | 78 -------------------
 2 files changed, 3 insertions(+), 81 deletions(-)
 delete mode 100644 runtime/Java/src/org/antlr/v4/runtime/misc/QStack.java

diff --git a/runtime/Java/src/org/antlr/v4/runtime/Lexer.java b/runtime/Java/src/org/antlr/v4/runtime/Lexer.java
index b6f7d84d5..b078b7f9e 100644
--- a/runtime/Java/src/org/antlr/v4/runtime/Lexer.java
+++ b/runtime/Java/src/org/antlr/v4/runtime/Lexer.java
@@ -29,8 +29,8 @@
 package org.antlr.v4.runtime;
 
 import org.antlr.v4.runtime.atn.LexerATNSimulator;
-import org.antlr.v4.runtime.misc.QStack;
 
+import java.util.ArrayDeque;
 import java.util.EmptyStackException;
 
 /** A lexer is recognizer that draws input symbols from a character stream.
@@ -85,7 +85,7 @@ public abstract class Lexer extends Recognizer<Integer, LexerATNSimulator>
 	/** The token type for the current token */
 	public int type;
 
-	public QStack<Integer> modeStack; // TODO: List?
+	public ArrayDeque<Integer> modeStack; // TODO: List?
 	public int mode = Lexer.DEFAULT_MODE;
 
 	/** You can set the text for the current token to override what is in
@@ -181,7 +181,7 @@ public abstract class Lexer extends Recognizer<Integer, LexerATNSimulator>
 
 	public void pushMode(int m) {
 		if ( LexerATNSimulator.debug ) System.out.println("pushMode "+m);
-		if ( modeStack==null ) modeStack = new QStack<Integer>();
+		if ( modeStack==null ) modeStack = new ArrayDeque<Integer>();
 		modeStack.push(mode);
 		mode(m);
 	}
diff --git a/runtime/Java/src/org/antlr/v4/runtime/misc/QStack.java b/runtime/Java/src/org/antlr/v4/runtime/misc/QStack.java
deleted file mode 100644
index d50791e2e..000000000
--- a/runtime/Java/src/org/antlr/v4/runtime/misc/QStack.java
+++ /dev/null
@@ -1,78 +0,0 @@
-/*
- [The "BSD license"]
- Copyright (c) 2011 Terence Parr
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions
- are met:
-
- 1. Redistributions of source code must retain the above copyright
-    notice, this list of conditions and the following disclaimer.
- 2. Redistributions in binary form must reproduce the above copyright
-    notice, this list of conditions and the following disclaimer in the
-    documentation and/or other materials provided with the distribution.
- 3. The name of the author may not be used to endorse or promote products
-    derived from this software without specific prior written permission.
-
- THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-package org.antlr.v4.runtime.misc;
-
-import java.util.EmptyStackException;
-
-/** A quicker stack than Stack */
-public class QStack<T> {
-	T[] elements;
-	public int sp = -1;
-
-	public QStack() {
-		elements = (T[])new Object[10];
-	}
-
-	public QStack(QStack s) {
-		elements = (T[])new Object[s.elements.length];
-		System.arraycopy(s.elements, 0, elements, 0, s.elements.length);
-		this.sp = s.sp;
-	}
-
-	public void push(T fset) {
-		if ( (sp+1)>=elements.length ) {
-			T[] f = (T[])new Object[elements.length*2];
-			System.arraycopy(elements, 0, f, 0, elements.length);
-			elements = f;
-		}
-		elements[++sp] = fset;
-	}
-
-	public T peek() {
-		if ( sp<0 ) throw new EmptyStackException();
-		return elements[sp];
-	}
-
-	public T get(int i) {
-		if ( i<0 ) throw new IllegalArgumentException("i<0");
-		if ( i>sp ) throw new IllegalArgumentException("i>"+sp);
-		return elements[sp];
-	}
-
-	public T pop() {
-		if ( sp<0 ) throw new EmptyStackException();
-		T o = elements[sp];
-		elements[sp] = null; // let gc reclaim that element
-		sp--;
-		return o;
-	}
-
-	public void clear() { sp = -1; }
-}