parquet.filter.ColumnPredicates Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of parquet-column Show documentation
The newest version!
/* 
 * 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 parquet.filter;

import parquet.Preconditions;
import parquet.column.ColumnReader;
import parquet.io.api.Binary;

/**
 * ColumnPredicates class provides checks for column values. Factory methods
 * are provided for standard predicates which wrap the job of getting the
 * correct value from the column.
 */
public class ColumnPredicates {

  public static interface Predicate {
    boolean apply(ColumnReader input);
  }

  public static interface PredicateFunction  {
    boolean functionToApply(T input);
  }

  /* provide the following to avoid boxing primitives */

  public static interface IntegerPredicateFunction {
    boolean functionToApply(int input);
  }

  public static interface LongPredicateFunction {
    boolean functionToApply(long input);
  }

  public static interface FloatPredicateFunction {
    boolean functionToApply(float input);
  }

  public static interface DoublePredicateFunction {
    boolean functionToApply(double input);
  }

  public static interface BooleanPredicateFunction {
    boolean functionToApply(boolean input);
  }

  public static Predicate equalTo(final String target) {
    Preconditions.checkNotNull(target,"target");
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return target.equals(input.getBinary().toStringUsingUTF8());
      }
    };
  }

  public static Predicate applyFunctionToString(final PredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
          return fn.functionToApply(input.getBinary().toStringUsingUTF8());
      }
    };
  }

  public static Predicate equalTo(final int target) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return input.getInteger() == target;
      }
    };
  }

  public static Predicate applyFunctionToInteger(final IntegerPredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return fn.functionToApply(input.getInteger());
      }
    };
  }

  public static Predicate equalTo(final long target) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return input.getLong() == target;
      }
    };
  }

  public static Predicate applyFunctionToLong(final LongPredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return fn.functionToApply(input.getLong());
      }
    };
  }

  public static Predicate equalTo(final float target) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return input.getFloat() == target;
      }
    };
  }

  public static Predicate applyFunctionToFloat(final FloatPredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return fn.functionToApply(input.getFloat());
      }
    };
  }

  public static Predicate equalTo(final double target) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return input.getDouble() == target;
      }
    };
  }

  public static Predicate applyFunctionToDouble(final DoublePredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return fn.functionToApply(input.getDouble());
      }
    };
  }

  public static Predicate equalTo(final boolean target) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return input.getBoolean() == target;
      }
    };
  }

  public static Predicate applyFunctionToBoolean (final BooleanPredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return fn.functionToApply(input.getBoolean());
      }
    };
  }

  public static  Predicate equalTo(final E target) {
    Preconditions.checkNotNull(target,"target");
    final String targetAsString = target.name();
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
        return targetAsString.equals(input.getBinary().toStringUsingUTF8());
      }
    };
  }

  public static Predicate applyFunctionToBinary (final PredicateFunction fn) {
    return new Predicate() {
      @Override
      public boolean apply(ColumnReader input) {
	  return fn.functionToApply(input.getBinary());
      }
    };
  }
}