src/main/java/net/hydromatic/linq4j/expressions/ForStatement.java

/*
// Licensed to Julian Hyde under one or more contributor license
// agreements. See the NOTICE file distributed with this work for
// additional information regarding copyright ownership.
//
// Julian Hyde 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 net.hydromatic.linq4j.expressions;

import net.hydromatic.linq4j.Ord;

import java.util.List;

/**
 * Represents an infinite loop. It can be exited with "break".
 */
public class ForStatement extends Statement {
  public final List<DeclarationStatement> declarations;
  public final Expression condition;
  public final Expression post;
  public final Statement body;

  public ForStatement(List<DeclarationStatement> declarations,
      Expression condition, Expression post, Statement body) {
    super(ExpressionType.For, Void.TYPE);
    assert declarations != null;
    assert body != null;
    this.declarations = declarations; // may be empty, not null
    this.condition = condition; // may be null
    this.post = post; // may be null
    this.body = body; // may be empty block, not null
  }

  @Override
  public ForStatement accept(Visitor visitor) {
    List<DeclarationStatement> decls1 =
        Expressions.acceptDeclarations(declarations, visitor);
    final Expression condition1 =
        condition == null ? null : condition.accept(visitor);
    final Expression post1 = post == null ? null : post.accept(visitor);
    final Statement body1 = body.accept(visitor);
    return visitor.visit(this, decls1, condition1, post1, body1);
  }

  @Override
  void accept0(ExpressionWriter writer) {
    writer.append("for (");
    for (Ord<DeclarationStatement> declaration : Ord.zip(declarations)) {
      declaration.e.accept2(writer, declaration.i == 0);
    }
    writer.append("; ");
    if (condition != null) {
      writer.append(condition);
    }
    writer.append("; ");
    if (post != null) {
      writer.append(post);
    }
    writer.append(") ").append(Blocks.toBlock(body));
  }
}

// End ForStatement.java