code: /**
   * This file is part of Eclipse Steady.
   *
   * Licensed 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.
   *
   * SPDX-License-Identifier: Apache-2.0
   * SPDX-FileCopyrightText: Copyright (c) 2018-2020 SAP SE or an SAP affiliate company and Eclipse Steady contributors
   */
  package org.eclipse.steady.shared.util;
  
  /**
   * <p>ProgressTracker class.</p>
   */
  public class ProgressTracker {
  
    private double total = -1;
    private double current = 0;
  
    /**
     * <p>Constructor for ProgressTracker.</p>
     *
     * @param _total a double.
     */
    public ProgressTracker(double _total) {
      this.total = _total;
    }
  
    /**
     * Returns the increase in percent of the total.
     *
     * @param _by a double.
     * @throws java.lang.IllegalArgumentException if the total is exceeded when adding _by to the current progress.
     * @return a double.
     */
    public double increase(double _by) throws IllegalArgumentException {
      if (this.current + _by > this.total) throw new IllegalArgumentException("Total exceeded");
      this.current += _by;
      return _by / this.total;
    }
  
    /**
     * <p>Getter for the field <code>current</code>.</p>
     *
     * @return a double.
     */
    public double getCurrent() {
      return this.current;
    }
  
    /**
     * <p>Getter for the field <code>total</code>.</p>
     *
     * @return a double.
     */
    public double getTotal() {
      return this.total;
    }
  
    /*
     * Returns the completion in percent.
     */
    /**
     * <p>getCompletion.</p>
     *
     * @return a double.
     */
    public double getCompletion() {
      return 100 * this.current / this.total;
    }
  
    /*
     * Returns the completion in percent.
     */
    /**
     * <p>getCompletionAsLong.</p>
     *
     * @return a long.
     */
    public long getCompletionAsLong() {
      return (long) Math.floor(this.getCompletion());
    }
  
    /** {@inheritDoc} */
    @Override
    public String toString() {
      final StringBuffer b = new StringBuffer();
      b.append(StringUtil.padLeft(String.format("%.2f", this.getCompletion()), 6)).append("%");
      b.append(" (")
          .append(StringUtil.padLeft(this.current, Double.toString(this.total).length()))
          .append(" / ")
          .append(this.total)
          .append(")");
      return b.toString();
    }
  }
  