/*
* Copyright (C) 2010, Marc Strapetz <marc.strapetz@syntevo.com>
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - 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.
*
* - Neither the name of the Eclipse Foundation, Inc. nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* 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 OWNER 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 org.eclipse.jgit.attributes;
/**
* Represents an attribute.
* <p>
* According to the man page, an attribute can have the following states:
* <ul>
* <li>Set - represented by {@link State#SET}</li>
* <li>Unset - represented by {@link State#UNSET}</li>
* <li>Set to a value - represented by {@link State#CUSTOM}</li>
* <li>Unspecified - used to revert an attribute . This is crucial in order to
* mark an attribute as unspecified in the attributes map and thus preventing
* following (with lower priority) nodes from setting the attribute to a value
* at all</li>
* </ul>
* </p>
*
* @since 3.7
*/
public final class Attribute {
/**
* The attribute value state
* see also https://www.kernel.org/pub/software/scm/git/docs/gitattributes.html
*/
public static enum State {
/** the attribute is set */
SET,
/** the attribute is unset */
UNSET,
/**
* the attribute appears as if it would not be defined at all
*
* @since 4.2
*/
UNSPECIFIED,
/** the attribute is set to a custom value */
CUSTOM
}
private final String key;
private final State state;
private final String value;
/**
* Creates a new instance
*
* @param key
* the attribute key. Should not be <code>null</code>.
* @param state
* the attribute state. It should be either {@link State#SET} or
* {@link State#UNSET}. In order to create a custom value
* attribute prefer the use of {@link #Attribute(String, String)}
* constructor.
*/
public Attribute(String key, State state) {
this(key, state, null);
}
private Attribute(String key, State state, String value) {
if (key == null)
throw new NullPointerException(
"The key of an attribute should not be null"); //$NON-NLS-1$
if (state == null)
throw new NullPointerException(
"The state of an attribute should not be null"); //$NON-NLS-1$
this.key = key;
this.state = state;
this.value = value;
}
/**
* Creates a new instance.
*
* @param key
* the attribute key. Should not be <code>null</code>.
* @param value
* the custom attribute value
*/
public Attribute(String key, String value) {
this(key, State.CUSTOM, value);
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!(obj instanceof Attribute))
return false;
Attribute other = (Attribute) obj;
if (!key.equals(other.key))
return false;
if (state != other.state)
return false;
if (value == null) {
if (other.value != null)
return false;
} else if (!value.equals(other.value))
return false;
return true;
}
/**
* @return the attribute key (never returns <code>null</code>)
*/
public String getKey() {
return key;
}
/**
* Returns the state.
*
* @return the state (never returns <code>null</code>)
*/
public State getState() {
return state;
}
/**
* @return the attribute value (may be <code>null</code>)
*/
public String getValue() {
return value;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + key.hashCode();
result = prime * result + state.hashCode();
result = prime * result + ((value == null) ? 0 : value.hashCode());
return result;
}
@Override
public String toString() {
switch (state) {
case SET:
return key;
case UNSET:
return "-" + key; //$NON-NLS-1$
case UNSPECIFIED:
return "!" + key; //$NON-NLS-1$
case CUSTOM:
default:
return key + "=" + value; //$NON-NLS-1$
}
}
}