Intial commit - import scenario 2

1 files changed, 180 insertions, 0 deletions

diff --git a/src/pl/edu/mimuw/cloudatlas/model/PathName.java b/src/pl/edu/mimuw/cloudatlas/model/PathName.java
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+/**
+ * Copyright (c) 2014, University of Warsaw
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR
+ * CONTRIBUTORS 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 pl.edu.mimuw.cloudatlas.model;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Represent a fully qualified name of a zone, also known as a global name or a path name. This class is immutable.
+ */
+public class PathName {
+	/**
+	 * The object representing a name of the root zone (/).
+	 */
+	public static final PathName ROOT = new PathName("/");
+	
+	private final List<String> components;
+	private final String name;
+	
+	/**
+	 * Creates a <code>PathName</code> object representing the specified path. For the root zone, there are three
+	 * accepted forms: <code>null</code> reference, empty string or slash. Any other zone is represented by a string
+	 * starting with slash and containing names of zones at each level of hierarchy, separated by slashes. Zone name
+	 * must contain only letters and digits.
+	 * 
+	 * @param name path name of a zone, for instance: <code>/warsaw/uw/violet07</code>
+	 * @throws IllegalArgumentException if the <code>name</code> is incorrect
+	 */
+	public PathName(String name) {
+		// we accept null and "/" as names of a root zone, however, we convert all of them to ""
+		name = name == null || name.equals("/")? "" : name.trim();
+		if(!name.matches("(/\\w+)*"))
+			throw new IllegalArgumentException("Incorrect fully qualified name: " + name + ".");
+		this.name = name;
+		components = name.equals("")? new ArrayList<String>() : Arrays.asList(name.substring(1).split("/"));
+	}
+	
+	/**
+	 * Creates a <code>PathName</code> object from a collection of zones names. Every zone name must contain only
+	 * letters and digits.
+	 * 
+	 * @param components a collection of zones names at subsequent levels of hierarchy (starting from root); empty
+	 * collection represents the root zone
+	 * @throws IllegalArgumentException if any zone name is incorrect
+	 */
+	public PathName(Collection<String> components) {
+		this.components = new ArrayList<String>(components);
+		if(components.isEmpty())
+			this.name = "";
+		else {
+			String currentName = "";
+			for(String c : components) {
+				currentName += "/" + c;
+				if(!c.matches("\\w+"))
+					throw new IllegalArgumentException("Incorrect component " + c + ".");
+			}
+			this.name = currentName;
+		}
+	}
+	
+	/**
+	 * Gets zones names at subsequent levels of hierarchy, starting from root. For the root zone, this method returns an
+	 * empty collection. Modifying returned list will throw an exception.
+	 * 
+	 * @return a collection of zones names
+	 */
+	public List<String> getComponents() {
+		return Collections.unmodifiableList(components);
+	}
+	
+	/**
+	 * Gets a full path name. For the root zone, this method returns an empty string.
+	 * 
+	 * @return a path name represented by this object
+	 * @see #toString()
+	 */
+	public String getName() {
+		return name;
+	}
+	
+	/**
+	 * Gets a name one level up in a hierarchy. For the root zone, this method returns a new instance of the same zone.
+	 * 
+	 * @return a new <code>PathName</code> object representing a zone one level up in the hierarchy
+	 */
+	public PathName levelUp() {
+		List<String> componentsUp = new ArrayList<String>(components);
+		if(!componentsUp.isEmpty())
+			componentsUp.remove(componentsUp.size() - 1);
+		return new PathName(componentsUp);
+	}
+	
+	/**
+	 * Gets a name one level down in a hierarchy.
+	 * 
+	 * @param son zone name at a lower level
+	 * @return a new <code>PathName</code> object representing a zone one level down in the hierarchy
+	 */
+	public PathName levelDown(String son) {
+		return new PathName(name + "/" + son);
+	}
+	
+	/**
+	 * Gets a zone name at the lowest level (highest number) in a hierarchy.
+	 * 
+	 * @return a leaf zone
+	 * @throws UnsupportedOperationException if this object represents the root zone
+	 */
+	public String getSingletonName() {
+		try {
+			return components.get(components.size() - 1);
+		} catch(IndexOutOfBoundsException exception) {
+			throw new UnsupportedOperationException("getSingletonName() is not supported for the root zone.");
+		}
+	}
+	
+	/**
+	 * Returns a hash code value for this object. This method returns a hash code of a string representing full path
+	 * name.
+	 * 
+	 * @return a hash code for this object
+	 */
+	@Override
+	public int hashCode() {
+		return name.hashCode();
+	}
+	
+	/**
+	 * Indicates whether this object is equal to another. A <code>PathName</code> object is equal to other objects of
+	 * the same class representing identical path name.
+	 * 
+	 * @object the object to check
+	 * @return whether the <code>object</code> is equal to this name
+	 */
+	@Override
+	public boolean equals(Object object) {
+		if(object == null)
+			return false;
+		if(getClass() != object.getClass())
+			return false;
+		return name.equals(((PathName)object).name);
+	}
+	
+	/**
+	 * Returns a textual representation for this <code>PathName</code>. For the root zone, unlike {@link #getName()},
+	 * this method returns slash.
+	 * 
+	 * @return a path name for this object
+	 * @see #getName()
+	 */
+	@Override
+	public String toString() {
+		return name.equals("")? "/" : getName();
+	}
+}