| /** |
| * 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.ratis.examples.arithmetic; |
| |
| import static org.apache.ratis.util.ProtoUtils.toByteString; |
| |
| import java.nio.charset.Charset; |
| import java.util.Map; |
| |
| import org.apache.ratis.examples.arithmetic.expression.Expression; |
| import org.apache.ratis.examples.arithmetic.expression.Variable; |
| import org.apache.ratis.protocol.Message; |
| import org.apache.ratis.thirdparty.com.google.protobuf.ByteString; |
| |
| public class AssignmentMessage implements Message, Evaluable { |
| public static final Charset UTF8 = Charset.forName("UTF-8"); |
| |
| private final Variable variable; |
| private final Expression expression; |
| |
| public AssignmentMessage(Variable variable, Expression expression) { |
| this.variable = variable; |
| this.expression = expression; |
| } |
| |
| public AssignmentMessage(byte[] buf, int offset) { |
| variable = new Variable(buf, offset); |
| expression = Expression.Utils.bytes2Expression(buf, offset + variable.length()); |
| } |
| |
| public AssignmentMessage(ByteString bytes) { |
| this(bytes.toByteArray(), 0); |
| } |
| |
| public Variable getVariable() { |
| return variable; |
| } |
| |
| public Expression getExpression() { |
| return expression; |
| } |
| |
| @Override |
| public ByteString getContent() { |
| final int length = variable.length() + expression.length(); |
| final byte[] bytes = new byte[length]; |
| final int offset = variable.toBytes(bytes, 0); |
| expression.toBytes(bytes, offset); |
| return toByteString(bytes); |
| } |
| |
| @Override |
| public String toString() { |
| return variable + " = " + expression; |
| } |
| |
| @Override |
| public Double evaluate(Map<String, Double> variableMap) { |
| final Double value = expression.evaluate(variableMap); |
| final String name = variable.getName(); |
| if (value == null) { |
| variableMap.remove(name); |
| } else { |
| variableMap.put(name, value); |
| } |
| return value; |
| } |
| } |