content: /**
   * 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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.atlas.groovy;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  
  /**
   * Groovy expression that represents a Groovy closure.
   */
  public class ClosureExpression extends AbstractGroovyExpression {
      private final List<VariableDeclaration> vars = new ArrayList<>();
      private final StatementListExpression   body = new StatementListExpression();
  
      public ClosureExpression(String... varNames) {
          this(null, varNames);
      }
  
      public ClosureExpression(GroovyExpression initialStmt, String... varNames) {
          this(Arrays.asList(varNames), initialStmt);
      }
  
      public ClosureExpression(List<String> varNames, GroovyExpression initialStmt) {
          if (initialStmt != null) {
              this.body.addStatement(initialStmt);
          }
  
          for (String varName : varNames) {
              vars.add(new VariableDeclaration(varName));
          }
      }
  
      public ClosureExpression(GroovyExpression initialStmt, List<VariableDeclaration> varNames) {
          if (initialStmt != null) {
              this.body.addStatement(initialStmt);
          }
  
          vars.addAll(varNames);
      }
  
      public void addStatement(GroovyExpression expr) {
          body.addStatement(expr);
      }
  
      public void addStatements(List<GroovyExpression> exprs) {
          body.addStatements(exprs);
      }
  
      public void replaceStatement(int index, GroovyExpression newExpr) {
          body.replaceStatement(index, newExpr);
      }
  
      @Override
      public void generateGroovy(GroovyGenerationContext context) {
          context.append("{");
  
          if (!vars.isEmpty()) {
              for (Iterator<VariableDeclaration> varIt = vars.iterator(); varIt.hasNext(); ) {
                  VariableDeclaration var = varIt.next();
  
                  var.append(context);
  
                  if (varIt.hasNext()) {
                      context.append(", ");
                  }
              }
  
              context.append("->");
          }
  
          body.generateGroovy(context);
  
          context.append("}");
      }
  
      @Override
      public List<GroovyExpression> getChildren() {
          return Collections.singletonList(body);
      }
  
      @Override
      public GroovyExpression copy(List<GroovyExpression> newChildren) {
          return new ClosureExpression(newChildren.get(0), vars);
      }
  
      public List<GroovyExpression> getStatements() {
          return body.getStatements();
      }
  
      /**
       * Variable declaration in a closure.
       */
      public static class VariableDeclaration {
          private final String type;
          private final String varName;
  
          public VariableDeclaration(String type, String varName) {
              super();
  
              this.type    = type;
              this.varName = varName;
          }
  
          public VariableDeclaration(String varName) {
              this(null, varName);
          }
  
          public void append(GroovyGenerationContext context) {
              if (type != null) {
                  context.append(type);
                  context.append(" ");
              }
  
              context.append(varName);
          }
      }
  }
  