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
   *
   * 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.calcite.adapter.os;
  
  import org.apache.calcite.DataContext;
  import org.apache.calcite.linq4j.Enumerable;
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.rel.type.RelDataTypeFactory;
  import org.apache.calcite.schema.ScannableTable;
  import org.apache.calcite.sql.type.SqlTypeName;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  /**
   * Table function that executes the OS "jps" ("Java Virtual Machine Process
   * Status Tool") command to list all java processes of a user.
   */
  public class JpsTableFunction {
    private JpsTableFunction() {
    }
  
    public static ScannableTable eval(boolean b) {
      return new AbstractBaseScannableTable() {
        @Override public Enumerable<@Nullable Object[]> scan(DataContext root) {
          return Processes.processLines("jps", "-mlvV")
              .select(a0 -> {
                final String[] fields = a0.split(" ");
                return new Object[]{Long.valueOf(fields[0]), fields[1]};
              });
        }
  
        @Override public RelDataType getRowType(RelDataTypeFactory typeFactory) {
          return typeFactory.builder()
              .add("pid", SqlTypeName.BIGINT)
              .add("info", SqlTypeName.VARCHAR)
              .build();
        }
      };
    }
  }
  