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A LWM2M client and server based on Californium (CoAP) all in one.
The newest version!
/*******************************************************************************
* Copyright (c) 2013-2015 Sierra Wireless and others.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Eclipse Distribution License v1.0 which accompany this distribution.
*
* The Eclipse Public License is available at
* http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.html.
*
* Contributors:
* Sierra Wireless - initial API and implementation
*******************************************************************************/
package org.eclipse.leshan;
import java.io.Serializable;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import org.eclipse.leshan.util.StringUtils;
/**
* A Link as defined in http://tools.ietf.org/html/rfc6690.
*/
// TODO this class has several problems :
// 1) Parsing is too permissive...
// e.g. it should not accept URI-Reference which are not between < >.
// e.g URI-reference should be parsed to respect RFC3986.
//
// 2) we should have Parser/Serializer class instead of static method to allow custom implementation.
// 3) attributes is not well named, it does not respect rfc naming : url => uriRef
//
// Maybe we could look at existing implementation :
// https://github.com/google/coapblaster/blob/master/src/main/java/com/google/iot/coap/LinkFormat.java
// https://github.com/eclipse/californium/blob/2.0.x/californium-core/src/main/java/org/eclipse/californium/core/coap/LinkFormat.java
// https://github.com/ARMmbed/java-coap/blob/master/coap-core/src/main/java/com/mbed/coap/linkformat/LinkFormat.java
public class Link implements Serializable {
private static final long serialVersionUID = 1L;
private final String url;
private final Map attributes;
/**
* Creates a new Link without attributes.
*
* @param url the object link URL
*/
public Link(String url) {
this(url, null);
}
/**
* Creates a new link and with its attributes.
*
* @param url the link URL
* @param attributes the object link attributes or null if the link has no attributes
*/
public Link(String url, Map attributes) {
this.url = url;
if (attributes != null) {
this.attributes = Collections.unmodifiableMap(new HashMap<>(attributes));
} else {
this.attributes = Collections.emptyMap();
}
}
public String getUrl() {
return url;
}
/**
* Gets the link attributes
*
* @return an unmodifiable map containing the link attributes
*/
public Map getAttributes() {
return attributes;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append('<');
builder.append(getUrl());
builder.append('>');
Map attributes = getAttributes();
if (attributes != null && !attributes.isEmpty()) {
for (Entry entry : attributes.entrySet()) {
builder.append(";");
builder.append(entry.getKey());
if (entry.getValue() != null) {
builder.append("=");
if (entry.getValue() instanceof String) {
builder.append("\"").append(entry.getValue()).append("\"");
} else {
builder.append(entry.getValue());
}
}
}
}
return builder.toString();
}
/**
* Parse a byte arrays representation of a {@code String} encoding with UTF_8 {@link Charset}.
*
* @param a byte arrays representing {@code String} encoding with UTF_8 {@link Charset}.
* @return an array of {@code Link}
*/
public static Link[] parse(byte[] content) {
if (content == null) {
return new Link[] {};
}
String s = new String(content, StandardCharsets.UTF_8);
String[] links = s.split(",");
Link[] linksResult = new Link[links.length];
int index = 0;
for (String link : links) {
String[] linkParts = link.split(";");
// clean URL
String url = StringUtils.trim(linkParts[0]);
url = StringUtils.removeStart(StringUtils.removeEnd(url, ">"), "<");
// parse attributes
Map attributes = new HashMap<>();
if (linkParts.length > 1) {
for (int i = 1; i < linkParts.length; i++) {
String[] attParts = linkParts[i].split("=");
if (attParts.length > 0) {
String key = attParts[0];
Object value = null;
if (attParts.length > 1) {
String rawvalue = attParts[1];
try {
value = Integer.valueOf(rawvalue);
} catch (NumberFormatException e) {
value = rawvalue.replaceFirst("^\"(.*)\"$", "$1");
}
}
attributes.put(key, value);
}
}
}
linksResult[index] = new Link(url, attributes);
index++;
}
return linksResult;
}
private static final String TRAILER = ", ";
/***
* Serialize severals {@code Link} to {@code String} as defined in http://tools.ietf.org/html/rfc6690.
*
* @param linkObjects links to serialize.
*
* @return a {@code String} representation like defined in http://tools.ietf.org/html/rfc6690. If LinkObjects is
* empty return an empty {@code String};
*/
public static String serialize(Link... linkObjects) {
StringBuilder builder = new StringBuilder();
if (linkObjects.length != 0) {
builder.append(linkObjects[0].toString());
for (int i = 1; i < linkObjects.length; i++) {
builder.append(TRAILER).append(linkObjects[i].toString());
}
}
return builder.toString();
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((attributes == null) ? 0 : attributes.hashCode());
result = prime * result + ((url == null) ? 0 : url.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Link other = (Link) obj;
if (attributes == null) {
if (other.attributes != null)
return false;
} else if (!attributes.equals(other.attributes))
return false;
if (url == null) {
if (other.url != null)
return false;
} else if (!url.equals(other.url))
return false;
return true;
}
}