/**
* 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.avro;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.io.IOException;
import org.apache.avro.util.internal.JacksonUtils;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.JsonGenerator;
import org.codehaus.jackson.node.TextNode;
/**
* Base class for objects that have JSON-valued properties. Avro and JSON values are
* represented in Java using the following mapping:
*
* <table>
* <th>
* <td>Avro type</td>
* <td>JSON type</td>
* <td>Java type</td>
* </th>
* <tr>
* <td><code>null</code></td>
* <td><code>null</code></td>
* <td>{@link #NULL_VALUE}</td>
* </tr>
* <tr>
* <td><code>boolean</code></td>
* <td>Boolean</td>
* <td><code>boolean</code></td>
* </tr>
* <tr>
* <td><code>int</code></td>
* <td>Number</td>
* <td><code>int</code></td>
* </tr>
* <tr>
* <td><code>long</code></td>
* <td>Number</td>
* <td><code>long</code></td>
* </tr>
* <tr>
* <td><code>float</code></td>
* <td>Number</td>
* <td><code>float</code></td>
* </tr>
* <tr>
* <td><code>double</code></td>
* <td>Number</td>
* <td><code>double</code></td>
* </tr>
* <tr>
* <td><code>bytes</code></td>
* <td>String</td>
* <td><code>byte[]</code></td>
* </tr>
* <tr>
* <td><code>string</code></td>
* <td>String</td>
* <td>{@link java.lang.String}</td>
* </tr>
* <tr>
* <td><code>record</code></td>
* <td>Object</td>
* <td>{@link java.util.Map}</td>
* </tr>
* <tr>
* <td><code>enum</code></td>
* <td>String</td>
* <td>{@link java.lang.String}</td>
* </tr>
* <tr>
* <td><code>array</code></td>
* <td>Array</td>
* <td>{@link java.util.Collection}</td>
* </tr>
* <tr>
* <td><code>map</code></td>
* <td>Object</td>
* <td>{@link java.util.Map}</td>
* </tr>
* <tr>
* <td><code>fixed</code></td>
* <td>String</td>
* <td><code>byte[]</code></td>
* </tr>
* </table>
*
* @see org.apache.avro.data.Json
*/
public abstract class JsonProperties {
public static class Null {
private Null() {}
}
/** A value representing a JSON <code>null</code>. */
public static final Null NULL_VALUE = new Null();
Map<String,JsonNode> props = new LinkedHashMap<String,JsonNode>(1);
private Set<String> reserved;
JsonProperties(Set<String> reserved) {
this.reserved = reserved;
}
/**
* Returns the value of the named, string-valued property in this schema.
* Returns <tt>null</tt> if there is no string-valued property with that name.
*/
public String getProp(String name) {
JsonNode value = getJsonProp(name);
return value != null && value.isTextual() ? value.getTextValue() : null;
}
/**
* Returns the value of the named property in this schema.
* Returns <tt>null</tt> if there is no property with that name.
* @deprecated use {@link #getObjectProp(String)}
*/
@Deprecated
public synchronized JsonNode getJsonProp(String name) {
return props.get(name);
}
/**
* Returns the value of the named property in this schema.
* Returns <tt>null</tt> if there is no property with that name.
*/
public synchronized Object getObjectProp(String name) {
return JacksonUtils.toObject(props.get(name));
}
/**
* Adds a property with the given name <tt>name</tt> and
* value <tt>value</tt>. Neither <tt>name</tt> nor <tt>value</tt> can be
* <tt>null</tt>. It is illegal to add a property if another with
* the same name but different value already exists in this schema.
*
* @param name The name of the property to add
* @param value The value for the property to add
*/
public void addProp(String name, String value) {
addProp(name, TextNode.valueOf(value));
}
/**
* Adds a property with the given name <tt>name</tt> and
* value <tt>value</tt>. Neither <tt>name</tt> nor <tt>value</tt> can be
* <tt>null</tt>. It is illegal to add a property if another with
* the same name but different value already exists in this schema.
*
* @param name The name of the property to add
* @param value The value for the property to add
* @deprecated use {@link #addProp(String, Object)}
*/
@Deprecated
public synchronized void addProp(String name, JsonNode value) {
if (reserved.contains(name))
throw new AvroRuntimeException("Can't set reserved property: " + name);
if (value == null)
throw new AvroRuntimeException("Can't set a property to null: " + name);
JsonNode old = props.get(name);
if (old == null)
props.put(name, value);
else if (!old.equals(value))
throw new AvroRuntimeException("Can't overwrite property: " + name);
}
public synchronized void addProp(String name, Object value) {
addProp(name, JacksonUtils.toJsonNode(value));
}
/** Return the defined properties that have string values. */
@Deprecated public Map<String,String> getProps() {
Map<String,String> result = new LinkedHashMap<String,String>();
for (Map.Entry<String,JsonNode> e : props.entrySet())
if (e.getValue().isTextual())
result.put(e.getKey(), e.getValue().getTextValue());
return result;
}
/** Convert a map of string-valued properties to Json properties. */
Map<String,JsonNode> jsonProps(Map<String,String> stringProps) {
Map<String,JsonNode> result = new LinkedHashMap<String,JsonNode>();
for (Map.Entry<String,String> e : stringProps.entrySet())
result.put(e.getKey(), TextNode.valueOf(e.getValue()));
return result;
}
/**
* Return the defined properties as an unmodifieable Map.
* @deprecated use {@link #getObjectProps()}
*/
@Deprecated
public Map<String,JsonNode> getJsonProps() {
return Collections.unmodifiableMap(props);
}
/** Return the defined properties as an unmodifieable Map. */
public Map<String,Object> getObjectProps() {
Map<String,Object> result = new LinkedHashMap<String,Object>();
for (Map.Entry<String,JsonNode> e : props.entrySet())
result.put(e.getKey(), JacksonUtils.toObject(e.getValue()));
return result;
}
void writeProps(JsonGenerator gen) throws IOException {
for (Map.Entry<String,JsonNode> e : props.entrySet())
gen.writeObjectField(e.getKey(), e.getValue());
}
}