org.apache.thrift.ShortStack Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.thrift;
/**
* ShortStack is a short-specific Stack implementation written for the express
* purpose of very fast operations on TCompactProtocol's field id stack. This
* implementation performs at least 10x faster than java.util.Stack.
*/
public class ShortStack {
private short[] vector;
private int top = -1;
public ShortStack(int initialCapacity) {
vector = new short[initialCapacity];
}
public short pop() {
return vector[top--];
}
public void push(short pushed) {
if (vector.length == top + 1) {
grow();
}
vector[++top] = pushed;
}
private void grow() {
short[] newVector = new short[vector.length * 2];
System.arraycopy(vector, 0, newVector, 0, vector.length);
vector = newVector;
}
public short peek() {
return vector[top];
}
public void clear() {
top = -1;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(">");
}
sb.append(vector[i]);
if (i == top) {
sb.append("<<");
}
}
sb.append("]>");
return sb.toString();
}
}