Java tutorial
/* * Licensed to CRATE Technology GmbH ("Crate") under one or more contributor * license agreements. See the NOTICE file distributed with this work for * additional information regarding copyright ownership. Crate 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. * * However, if you have executed another commercial license agreement * with Crate these terms will supersede the license and you may use the * software solely pursuant to the terms of the relevant commercial agreement. */ package io.crate.sql.tree; import com.google.common.base.MoreObjects; import com.google.common.base.Objects; import com.google.common.base.Optional; import javax.annotation.Nullable; import static com.google.common.base.Preconditions.checkNotNull; public class ShowColumns extends Statement { private final QualifiedName table; private final Optional<QualifiedName> schema; private final Optional<String> likePattern; private final Optional<Expression> where; public ShowColumns(QualifiedName table, @Nullable QualifiedName schema, @Nullable String likePattern) { this.table = checkNotNull(table, "table is null"); this.schema = Optional.fromNullable(schema); this.likePattern = Optional.fromNullable(likePattern); this.where = Optional.absent(); } public ShowColumns(QualifiedName table, @Nullable QualifiedName schema, @Nullable Expression where) { this.table = checkNotNull(table, "table is null"); this.where = Optional.fromNullable(where); this.schema = Optional.fromNullable(schema); this.likePattern = Optional.absent(); } public QualifiedName table() { return table; } public Optional<QualifiedName> schema() { return schema; } public Optional<String> likePattern() { return likePattern; } public Optional<Expression> where() { return where; } @Override public <R, C> R accept(AstVisitor<R, C> visitor, C context) { return visitor.visitShowColumns(this, context); } @Override public int hashCode() { return Objects.hashCode(table, schema, likePattern); } @Override public boolean equals(Object obj) { if (this == obj) { return true; } if ((obj == null) || (getClass() != obj.getClass())) { return false; } ShowColumns o = (ShowColumns) obj; return Objects.equal(table, o.table) && Objects.equal(schema, o.schema) && Objects.equal(likePattern, o.likePattern) && Objects.equal(where, o.where); } @Override public String toString() { return MoreObjects.toStringHelper(this).add("table", table).add("schema", schema) .add("pattern", likePattern).add("where", where).toString(); } }