org.apache.gora.filter.MapFieldValueFilter.java Source code

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Here is the source code for org.apache.gora.filter.MapFieldValueFilter.java

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/**
 * 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.gora.filter;

import org.apache.avro.util.Utf8;
import org.apache.gora.persistency.impl.PersistentBase;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.ObjectWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.WritableUtils;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * A filter that checks for a single field in the persistent.
 * 
 * @param <K>
 * @param <T>
 */
public class MapFieldValueFilter<K, T extends PersistentBase> implements Filter<K, T> {

    protected String fieldName;
    protected Utf8 mapKey;
    protected FilterOp filterOp;
    protected List<Object> operands = new ArrayList<Object>();
    protected boolean filterIfMissing = false;

    private Configuration conf = new Configuration(); // just create empty conf,
                                                      // needed for ObjectWritable

    @Override
    public void write(DataOutput out) throws IOException {
        Text.writeString(out, fieldName);
        Text.writeString(out, mapKey.toString());
        WritableUtils.writeEnum(out, filterOp);
        WritableUtils.writeVInt(out, operands.size());
        for (int i = 0; i < operands.size(); i++) {
            Object operand = operands.get(i);
            if (operand instanceof String) {
                throw new IllegalStateException("Use Utf8 instead of String for operands");
            }
            if (operand instanceof Utf8) {
                operand = operand.toString();
            }
            if (operand instanceof Boolean) {
                ObjectWritable.writeObject(out, operand, Boolean.TYPE, conf);
            } else if (operand instanceof Character) {
                ObjectWritable.writeObject(out, operand, Character.TYPE, conf);
            } else if (operand instanceof Byte) {
                ObjectWritable.writeObject(out, operand, Byte.TYPE, conf);
            } else if (operand instanceof Short) {
                ObjectWritable.writeObject(out, operand, Short.TYPE, conf);
            } else if (operand instanceof Integer) {
                ObjectWritable.writeObject(out, operand, Integer.TYPE, conf);
            } else if (operand instanceof Long) {
                ObjectWritable.writeObject(out, operand, Long.TYPE, conf);
            } else if (operand instanceof Float) {
                ObjectWritable.writeObject(out, operand, Float.TYPE, conf);
            } else if (operand instanceof Double) {
                ObjectWritable.writeObject(out, operand, Double.TYPE, conf);
            } else if (operand instanceof Void) {
                ObjectWritable.writeObject(out, operand, Void.TYPE, conf);
            } else {
                ObjectWritable.writeObject(out, operand, operand.getClass(), conf);
            }
        }
        out.writeBoolean(filterIfMissing);
    }

    @Override
    public void readFields(DataInput in) throws IOException {
        fieldName = Text.readString(in);
        mapKey = new Utf8(Text.readString(in));
        filterOp = WritableUtils.readEnum(in, FilterOp.class);
        operands.clear();
        int operandsSize = WritableUtils.readVInt(in);
        for (int i = 0; i < operandsSize; i++) {
            Object operand = ObjectWritable.readObject(in, conf);
            if (operand instanceof String) {
                operand = new Utf8((String) operand);
            }
            operands.add(operand);
        }
        filterIfMissing = in.readBoolean();
    }

    @Override
    public boolean filter(K key, T persistent) {
        int fieldIndex = persistent.getSchema().getField(fieldName).pos();
        @SuppressWarnings("unchecked")
        Map<Utf8, ?> fieldValue = (Map<Utf8, ?>) persistent.get(fieldIndex);
        if (fieldValue == null) {
            return filterIfMissing;
        }
        Object value = fieldValue.get(mapKey);
        Object operand = operands.get(0);
        if (value == null) {
            return filterIfMissing;
        }
        if (filterOp.equals(FilterOp.EQUALS)) {
            boolean equals = value.equals(operand);
            return !equals;
        } else if (filterOp.equals(FilterOp.NOT_EQUALS)) {
            boolean equals = value.equals(operand);
            return equals;
        } else {
            throw new IllegalStateException(filterOp + " not yet implemented");
        }
    }

    public String getFieldName() {
        return fieldName;
    }

    public void setFieldName(String fieldName) {
        this.fieldName = fieldName;
    }

    public Utf8 getMapKey() {
        return mapKey;
    }

    public void setMapKey(Utf8 mapKey) {
        this.mapKey = mapKey;
    }

    public FilterOp getFilterOp() {
        return filterOp;
    }

    public void setFilterOp(FilterOp filterOp) {
        this.filterOp = filterOp;
    }

    public List<Object> getOperands() {
        return operands;
    }

    public void setOperands(List<Object> operands) {
        this.operands = operands;
    }

    public void setFilterIfMissing(boolean filterIfMissing) {
        this.filterIfMissing = filterIfMissing;
    }

    public boolean isFilterIfMissing() {
        return filterIfMissing;
    }

    @Override
    public String toString() {
        return "SingleFieldValueFilter [fieldName=" + fieldName + ",mapKey=" + mapKey + ", filterOp=" + filterOp
                + ", operands=" + operands + ", filterIfMissing=" + filterIfMissing + "]";
    }
}