Java tutorial
/** * 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.drill.exec.vector.complex.fn; import java.io.IOException; import java.math.BigDecimal; import org.apache.drill.common.types.TypeProtos.MinorType; import org.apache.drill.exec.expr.fn.impl.DateUtility; import org.apache.drill.exec.vector.complex.reader.FieldReader; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.joda.time.Period; import org.joda.time.format.DateTimeFormatter; import org.joda.time.format.ISODateTimeFormat; import org.joda.time.format.ISOPeriodFormat; import com.fasterxml.jackson.core.JsonGenerator; import com.google.common.base.Preconditions; /** * A JSON output class that generates standard JSON. By default, literals are output such that they can be implicitly * cast. */ public class BasicJsonOutput implements JsonOutput { protected final JsonGenerator gen; private final DateTimeFormatter dateFormatter; private final DateTimeFormatter timeFormatter; private final DateTimeFormatter timestampFormatter; public BasicJsonOutput(JsonGenerator gen) { this(gen, DateOutputFormat.SQL); } protected BasicJsonOutput(JsonGenerator gen, DateOutputFormat dateOutput) { Preconditions.checkNotNull(dateOutput); Preconditions.checkNotNull(gen); this.gen = gen; switch (dateOutput) { case SQL: { dateFormatter = DateUtility.formatDate; timeFormatter = DateUtility.formatTime; timestampFormatter = DateUtility.formatTimeStamp; break; } case ISO: { dateFormatter = ISODateTimeFormat.date(); timeFormatter = ISODateTimeFormat.time(); timestampFormatter = ISODateTimeFormat.dateTime(); break; } default: throw new UnsupportedOperationException( String.format("Unable to support date output of type %s.", dateOutput)); } } @Override public void flush() throws IOException { gen.flush(); } @Override public void writeStartArray() throws IOException { gen.writeStartArray(); } @Override public void writeEndArray() throws IOException { gen.writeEndArray(); } @Override public void writeStartObject() throws IOException { gen.writeStartObject(); } @Override public void writeEndObject() throws IOException { gen.writeEndObject(); } @Override public void writeUntypedNull() throws IOException { gen.writeNull(); } @Override public void writeFieldName(String name) throws IOException { gen.writeFieldName(name); } @Override public void writeDecimal(FieldReader reader) throws IOException { if (reader.isSet()) { writeDecimal(reader.readBigDecimal()); } else { writeDecimalNull(); } } @Override public void writeTinyInt(FieldReader reader) throws IOException { if (reader.isSet()) { writeTinyInt(reader.readByte()); } else { writeTinyIntNull(); } } @Override public void writeSmallInt(FieldReader reader) throws IOException { if (reader.isSet()) { writeSmallInt(reader.readShort()); } else { writeSmallIntNull(); } } @Override public void writeInt(FieldReader reader) throws IOException { if (reader.isSet()) { writeInt(reader.readInteger()); } else { writeIntNull(); } } @Override public void writeBigInt(FieldReader reader) throws IOException { if (reader.isSet()) { writeBigInt(reader.readLong()); } else { writeBigIntNull(); } } @Override public void writeFloat(FieldReader reader) throws IOException { if (reader.isSet()) { writeFloat(reader.readFloat()); } else { writeFloatNull(); } } @Override public void writeDouble(FieldReader reader) throws IOException { if (reader.isSet()) { writeDouble(reader.readDouble()); } else { writeDoubleNull(); } } @Override public void writeVarChar(FieldReader reader) throws IOException { if (reader.isSet()) { writeVarChar(reader.readText().toString()); } else { writeVarcharNull(); } } @Override public void writeVar16Char(FieldReader reader) throws IOException { if (reader.isSet()) { writeVar16Char(reader.readText().toString()); } else { writeVar16charNull(); } } @Override public void writeBinary(FieldReader reader) throws IOException { if (reader.isSet()) { writeBinary(reader.readByteArray()); } else { writeBinaryNull(); } } @Override public void writeBoolean(FieldReader reader) throws IOException { if (reader.isSet()) { writeBoolean(reader.readBoolean()); } else { writeBooleanNull(); } } @Override public void writeDate(FieldReader reader) throws IOException { if (reader.isSet()) { writeDate(reader.readDateTime()); } else { writeDateNull(); } } @Override public void writeTime(FieldReader reader) throws IOException { if (reader.isSet()) { writeTime(reader.readDateTime()); } else { writeTimeNull(); } } @Override public void writeTimestamp(FieldReader reader) throws IOException { if (reader.isSet()) { writeTimestamp(reader.readDateTime()); } else { writeTimeNull(); } } @Override public void writeInterval(FieldReader reader) throws IOException { if (reader.isSet()) { writeInterval(reader.readPeriod()); } else { writeIntervalNull(); } } @Override public void writeTinyInt(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeTinyInt(reader.readByte(index)); } else { writeTinyIntNull(); } } @Override public void writeSmallInt(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeSmallInt(reader.readShort(index)); } else { writeSmallIntNull(); } } @Override public void writeInt(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeInt(reader.readInteger(index)); } else { writeIntNull(); } } @Override public void writeBigInt(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeBigInt(reader.readLong(index)); } else { writeBigIntNull(); } } @Override public void writeFloat(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeFloat(reader.readFloat(index)); } else { writeFloatNull(); } } @Override public void writeDouble(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeDouble(reader.readDouble(index)); } else { writeDoubleNull(); } } @Override public void writeVarChar(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeVarChar(reader.readText(index).toString()); } else { writeVarcharNull(); } } @Override public void writeVar16Char(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeVar16Char(reader.readString(index)); } else { writeVar16charNull(); } } @Override public void writeBinary(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeBinary(reader.readByteArray(index)); } else { writeBinaryNull(); } } @Override public void writeBoolean(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeBoolean(reader.readBoolean(index)); } else { writeBooleanNull(); } } @Override public void writeDate(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeDate(reader.readDateTime(index)); } else { writeDateNull(); } } @Override public void writeTime(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeTime(reader.readDateTime(index)); } else { writeTimeNull(); } } @Override public void writeTimestamp(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeTimestamp(reader.readDateTime(index)); } else { writeTimestampNull(); } } @Override public void writeInterval(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeInterval(reader.readPeriod(index)); } else { writeIntervalNull(); } } @Override public void writeDecimal(int index, FieldReader reader) throws IOException { if (reader.isSet()) { writeDecimal(reader.readBigDecimal(index)); } else { writeDecimalNull(); } } @Override public void writeDecimal(BigDecimal value) throws IOException { gen.writeNumber(value); } @Override public void writeTinyInt(byte value) throws IOException { gen.writeNumber(value); } @Override public void writeSmallInt(short value) throws IOException { gen.writeNumber(value); } @Override public void writeInt(int value) throws IOException { gen.writeNumber(value); } @Override public void writeBigInt(long value) throws IOException { gen.writeNumber(value); } @Override public void writeFloat(float value) throws IOException { gen.writeNumber(value); } @Override public void writeDouble(double value) throws IOException { gen.writeNumber(value); } @Override public void writeVarChar(String value) throws IOException { gen.writeString(value); } @Override public void writeVar16Char(String value) throws IOException { gen.writeString(value); } @Override public void writeBinary(byte[] value) throws IOException { gen.writeBinary(value); } @Override public void writeBoolean(boolean value) throws IOException { gen.writeBoolean(value); } @Override public void writeDate(DateTime value) throws IOException { gen.writeString(dateFormatter.print(value.withZone(DateTimeZone.UTC))); } @Override public void writeTime(DateTime value) throws IOException { gen.writeString(timeFormatter.print(value.withZone(DateTimeZone.UTC))); } @Override public void writeTimestamp(DateTime value) throws IOException { gen.writeString(timestampFormatter.print(value.withZone(DateTimeZone.UTC))); } @Override public void writeInterval(Period value) throws IOException { gen.writeString(value.toString(ISOPeriodFormat.standard())); } @Override public void writeDecimalNull() throws IOException { gen.writeNull(); } @Override public void writeTinyIntNull() throws IOException { gen.writeNull(); } @Override public void writeSmallIntNull() throws IOException { gen.writeNull(); } @Override public void writeIntNull() throws IOException { gen.writeNull(); } @Override public void writeBigIntNull() throws IOException { gen.writeNull(); } @Override public void writeFloatNull() throws IOException { gen.writeNull(); } @Override public void writeDoubleNull() throws IOException { gen.writeNull(); } @Override public void writeVarcharNull() throws IOException { gen.writeNull(); } @Override public void writeVar16charNull() throws IOException { gen.writeNull(); } @Override public void writeBinaryNull() throws IOException { gen.writeNull(); } @Override public void writeBooleanNull() throws IOException { gen.writeNull(); } @Override public void writeDateNull() throws IOException { gen.writeNull(); } @Override public void writeTimeNull() throws IOException { gen.writeNull(); } @Override public void writeTimestampNull() throws IOException { gen.writeNull(); } @Override public void writeIntervalNull() throws IOException { gen.writeNull(); } }