Example of a Java class to generate a Beam Schema and convert between the Object and Row.

SomeThing.java

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 * to you under the Apache License, Version 2.0 (the
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package example;

import com.google.auto.value.AutoValue;
import org.apache.beam.sdk.schemas.AutoValueSchema;
import org.apache.beam.sdk.schemas.Schema;
import org.apache.beam.sdk.schemas.SchemaProvider;
import org.apache.beam.sdk.schemas.annotations.DefaultSchema;
import org.apache.beam.sdk.transforms.SerializableFunction;
import org.apache.beam.sdk.values.Row;
import org.apache.beam.sdk.values.TypeDescriptor;

import static org.apache.beam.sdk.util.Preconditions.checkStateNotNull;

@DefaultSchema(AutoValueSchema.class)
@AutoValue
abstract class SomeThing {

    private static final SchemaProvider SCHEMA_PROVIDER = new AutoValueSchema();

    private static final TypeDescriptor<SomeThing> TYPE_DESCRIPTOR = TypeDescriptor.of(SomeThing.class);

    private static final SerializableFunction<SomeThing, Row> TO_ROW_FN = checkStateNotNull(SCHEMA_PROVIDER.toRowFunction(TYPE_DESCRIPTOR));

    private static final SerializableFunction<Row, SomeThing> FROM_ROW_FN = checkStateNotNull(SCHEMA_PROVIDER.fromRowFunction(TYPE_DESCRIPTOR));

    static final Schema SCHEMA = checkStateNotNull(SCHEMA_PROVIDER.schemaFor(TYPE_DESCRIPTOR));

    Row toRow() {
        return TO_ROW_FN.apply(this);
    }

    static SomeThing fromRow(Row row) {
        return FROM_ROW_FN.apply(row);
    }

    abstract Boolean getABoolean();

    abstract String getAString();

    abstract Integer getAnInteger();

    abstract Long getALong();

    abstract Float getAFloat();

    abstract Double getADouble();

    @AutoValue.Builder
    abstract static class Builder {
        abstract Builder setABoolean(Boolean aBoolean);

        abstract Builder setAString(String value);

        abstract Builder setAnInteger(Integer value);

        abstract Builder setALong(Long value);

        abstract Builder setAFloat(Float value);

        abstract Builder setADouble(Double value);

        abstract SomeThing build();
    }
}