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com.amazonaws.services.dynamodbv2.datamodeling.StandardTypeConverters Maven / Gradle / Ivy
/*
* Copyright 2016-2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed 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://aws.amazon.com/apache2.0
*
* This file 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 com.amazonaws.services.dynamodbv2.datamodeling;
import com.amazonaws.annotation.SdkInternalApi;
import com.amazonaws.services.dynamodbv2.model.ScalarAttributeType;
import com.amazonaws.util.DateUtils;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.util.AbstractMap.SimpleImmutableEntry;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Calendar;
import java.util.Currency;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TimeZone;
import java.util.regex.Pattern;
import org.joda.time.DateTime;
/**
* Type conversions.
*
* @see com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTypeConverter
*/
@SdkInternalApi
final class StandardTypeConverters extends DynamoDBTypeConverterFactory {
/**
* Standard scalar type-converter factory.
*/
private static final DynamoDBTypeConverterFactory FACTORY = new StandardTypeConverters();
static DynamoDBTypeConverterFactory factory() {
return StandardTypeConverters.FACTORY;
}
/**
* {@inheritDoc}
*/
@Override
public DynamoDBTypeConverter getConverter(Class sourceType, Class targetType) {
final Scalar source = Scalar.of(sourceType), target = Scalar.of(targetType);
final Converter toSource = source.getConverter(sourceType, target.type());
final Converter toTarget = target.getConverter(targetType, source.type());
return new DynamoDBTypeConverter() {
@Override
public final S convert(final T o) {
return toSource.convert(o);
}
@Override
public final T unconvert(final S o) {
return toTarget.convert(o);
}
};
}
/**
* Standard scalar types.
*/
static enum Scalar {
/**
* {@link BigDecimal}
*/
BIG_DECIMAL(ScalarAttributeType.N, new ConverterMap(BigDecimal.class, null)
.with(Number.class, ToBigDecimal.FromString.join(ToString.FromNumber))
.with(String.class, ToBigDecimal.FromString)
),
/**
* {@link BigInteger}
*/
BIG_INTEGER(ScalarAttributeType.N, new ConverterMap(BigInteger.class, null)
.with(Number.class, ToBigInteger.FromString.join(ToString.FromNumber))
.with(String.class, ToBigInteger.FromString)
),
/**
* {@link Boolean}
*/
BOOLEAN(ScalarAttributeType.N, new ConverterMap(Boolean.class, Boolean.TYPE)
.with(Number.class, ToBoolean.FromString.join(ToString.FromNumber))
.with(String.class, ToBoolean.FromString)
),
/**
* {@link Byte}
*/
BYTE(ScalarAttributeType.N, new ConverterMap(Byte.class, Byte.TYPE)
.with(Number.class, ToByte.FromNumber)
.with(String.class, ToByte.FromString)
),
/**
* {@link Byte} array
*/
BYTE_ARRAY(ScalarAttributeType.B, new ConverterMap(byte[].class, null)
.with(ByteBuffer.class, ToByteArray.FromByteBuffer)
.with(String.class, ToByteArray.FromString)
),
/**
* {@link ByteBuffer}
*/
BYTE_BUFFER(ScalarAttributeType.B, new ConverterMap(ByteBuffer.class, null)
.with(byte[].class, ToByteBuffer.FromByteArray)
.with(String.class, ToByteBuffer.FromByteArray.join(ToByteArray.FromString))
.with(java.util.UUID.class, ToByteBuffer.FromUuid)
),
/**
* {@link Calendar}
*/
CALENDAR(ScalarAttributeType.S, new ConverterMap(Calendar.class, null)
.with(Date.class, ToCalendar.FromDate)
.with(DateTime.class, ToCalendar.FromDate.join(ToDate.FromDateTime))
.with(Long.class, ToCalendar.FromDate.join(ToDate.FromLong))
.with(String.class, ToCalendar.FromDate.join(ToDate.FromString))
),
/**
* {@link Character}
*/
CHARACTER(ScalarAttributeType.S, new ConverterMap(Character.class, Character.TYPE)
.with(String.class, ToCharacter.FromString)
),
/**
* {@link Currency}
*/
CURRENCY(ScalarAttributeType.S, new ConverterMap(Currency.class, null)
.with(String.class, ToCurrency.FromString)
),
/**
* {@link Date}
*/
DATE(ScalarAttributeType.S, new ConverterMap(Date.class, null)
.with(Calendar.class, ToDate.FromCalendar)
.with(DateTime.class, ToDate.FromDateTime)
.with(Long.class, ToDate.FromLong)
.with(String.class, ToDate.FromString)
),
/**
* {@link DateTime}
*/
DATE_TIME(/*ScalarAttributeType.S*/null, new ConverterMap(DateTime.class, null)
.with(Calendar.class, ToDateTime.FromDate.join(ToDate.FromCalendar))
.with(Date.class, ToDateTime.FromDate)
.with(Long.class, ToDateTime.FromDate.join(ToDate.FromLong))
.with(String.class, ToDateTime.FromDate.join(ToDate.FromString))
),
/**
* {@link Double}
*/
DOUBLE(ScalarAttributeType.N, new ConverterMap(Double.class, Double.TYPE)
.with(Number.class, ToDouble.FromNumber)
.with(String.class, ToDouble.FromString)
),
/**
* {@link Float}
*/
FLOAT(ScalarAttributeType.N, new ConverterMap(Float.class, Float.TYPE)
.with(Number.class, ToFloat.FromNumber)
.with(String.class, ToFloat.FromString)
),
/**
* {@link Integer}
*/
INTEGER(ScalarAttributeType.N, new ConverterMap(Integer.class, Integer.TYPE)
.with(Number.class, ToInteger.FromNumber)
.with(String.class, ToInteger.FromString)
),
/**
* {@link Locale}
*/
LOCALE(ScalarAttributeType.S, new ConverterMap(Locale.class, null)
.with(String.class, ToLocale.FromString)
),
/**
* {@link Long}
*/
LONG(ScalarAttributeType.N, new ConverterMap(Long.class, Long.TYPE)
.with(Date.class, ToLong.FromDate)
.with(DateTime.class, ToLong.FromDate.join(ToDate.FromDateTime))
.with(Calendar.class, ToLong.FromDate.join(ToDate.FromCalendar))
.with(Number.class, ToLong.FromNumber)
.with(String.class, ToLong.FromString)
),
/**
* {@link S3Link}
*/
S3_LINK(ScalarAttributeType.S, new ConverterMap(S3Link.class, null)),
/**
* {@link Short}
*/
SHORT(ScalarAttributeType.N, new ConverterMap(Short.class, Short.TYPE)
.with(Number.class, ToShort.FromNumber)
.with(String.class, ToShort.FromString)
),
/**
* {@link String}
*/
STRING(ScalarAttributeType.S, new ConverterMap(String.class, null)
.with(Boolean.class, ToString.FromBoolean)
.with(byte[].class, ToString.FromByteArray)
.with(ByteBuffer.class, ToString.FromByteArray.join(ToByteArray.FromByteBuffer))
.with(Calendar.class, ToString.FromDate.join(ToDate.FromCalendar))
.with(Date.class, ToString.FromDate)
.with(Enum.class, ToString.FromEnum)
.with(Locale.class, ToString.FromLocale)
.with(TimeZone.class, ToString.FromTimeZone)
.with(Object.class, ToString.FromObject)
),
/**
* {@link TimeZone}
*/
TIME_ZONE(ScalarAttributeType.S, new ConverterMap(TimeZone.class, null)
.with(String.class, ToTimeZone.FromString)
),
/**
* {@link java.net.URL}
*/
URL(ScalarAttributeType.S, new ConverterMap(java.net.URL.class, null)
.with(String.class, ToUrl.FromString)
),
/**
* {@link java.net.URI}
*/
URI(ScalarAttributeType.S, new ConverterMap(java.net.URI.class, null)
.with(String.class, ToUri.FromString)
),
/**
* {@link java.util.UUID}
*/
UUID(ScalarAttributeType.S, new ConverterMap(java.util.UUID.class, null)
.with(ByteBuffer.class, ToUuid.FromByteBuffer)
.with(String.class, ToUuid.FromString)
),
/**
* {@link Object}; default must be last
*/
DEFAULT(null, new ConverterMap(Object.class, null)) {
@Override
Converter getConverter(Class sourceType, Class targetType) {
if (sourceType.isEnum() && STRING.map.isAssignableFrom(targetType)) {
return (Converter)new ToEnum.FromString(sourceType);
}
return super.getConverter(sourceType, targetType);
}
};
/**
* The scalar attribute type.
*/
private final ScalarAttributeType scalarAttributeType;
/**
* The mapping of conversion functions for this scalar.
*/
private final ConverterMap map;
/**
* Constructs a new scalar with the specified conversion mappings.
*/
private Scalar(ScalarAttributeType scalarAttributeType, ConverterMap map) {
this.scalarAttributeType = scalarAttributeType;
this.map = map;
}
/**
* Returns the function to convert from the specified target class to
* this scalar type.
*/
Converter getConverter(Class sourceType, Class targetType) {
return map.getConverter(targetType);
}
/**
* Converts the target instance using the standard type-conversions.
*/
@SuppressWarnings("unchecked")
final S convert(Object o) {
return getConverter(this.type(), (Class)o.getClass()).convert(o);
}
/**
* Determines if the scalar is of the specified scalar attribute type.
*/
final boolean is(final ScalarAttributeType scalarAttributeType) {
return this.scalarAttributeType == scalarAttributeType;
}
/**
* Determines if the class represented by this scalar is either the
* same as or a supertype of the specified target type.
*/
final boolean is(final Class type) {
return this.map.isAssignableFrom(type);
}
/**
* Returns the primary reference type.
*/
@SuppressWarnings("unchecked")
final Class type() {
return (Class)this.map.referenceType;
}
/**
* Returns the first matching scalar, which may be the same as or a
* supertype of the specified target class.
*/
static Scalar of(Class type) {
for (final Scalar scalar : Scalar.values()) {
if (scalar.is(type)) {
return scalar;
}
}
return DEFAULT;
}
}
/**
* Standard vector types.
*/
static abstract class Vector {
/**
* {@link List}
*/
static final ToList LIST = new ToList();
static final class ToList extends Vector {
DynamoDBTypeConverter,List> join(final DynamoDBTypeConverter scalar) {
return new DynamoDBTypeConverter,List>() {
@Override
public final List convert(final List o) {
return LIST.convert(o, scalar);
}
@Override
public final List unconvert(final List o) {
return LIST.unconvert(o, scalar);
}
};
}
List convert(Collection o, DynamoDBTypeConverter scalar) {
final List vector = new ArrayList(o.size());
for (final T t : o) {
vector.add(scalar.convert(t));
}
return vector;
}
List unconvert(Collection o, DynamoDBTypeConverter scalar) {
final List vector = new ArrayList(o.size());
for (final S s : o) {
vector.add(scalar.unconvert(s));
}
return vector;
}
@Override
boolean is(final Class type) {
return List.class.isAssignableFrom(type);
}
}
/**
* {@link Map}
*/
static final ToMap MAP = new ToMap();
static final class ToMap extends Vector {
DynamoDBTypeConverter,Map> join(final DynamoDBTypeConverter scalar) {
return new DynamoDBTypeConverter,Map>() {
@Override
public final Map convert(final Map o) {
return MAP.convert(o, scalar);
}
@Override
public final Map unconvert(final Map o) {
return MAP.unconvert(o, scalar);
}
};
}
Map convert(Map o, DynamoDBTypeConverter scalar) {
final Map vector = new LinkedHashMap();
for (final Map.Entry t : o.entrySet()) {
vector.put(t.getKey(), scalar.convert(t.getValue()));
}
return vector;
}
Map unconvert(Map o, DynamoDBTypeConverter scalar) {
final Map vector = new LinkedHashMap();
for (final Map.Entry s : o.entrySet()) {
vector.put(s.getKey(), scalar.unconvert(s.getValue()));
}
return vector;
}
boolean is(final Class type) {
return Map.class.isAssignableFrom(type);
}
}
/**
* {@link Set}
*/
static final ToSet SET = new ToSet();
static final class ToSet extends Vector {
DynamoDBTypeConverter,Collection> join(final DynamoDBTypeConverter target) {
return new DynamoDBTypeConverter,Collection>() {
@Override
public List convert(final Collection o) {
return LIST.convert(o, target);
}
@Override
public Collection unconvert(final List o) {
return SET.unconvert(o, target);
}
};
}
Set unconvert(Collection o, DynamoDBTypeConverter scalar) {
final Set vector = new LinkedHashSet();
for (final S s : o) {
if (vector.add(scalar.unconvert(s)) == false) {
throw new DynamoDBMappingException("duplicate value (" + s + ")");
}
}
return vector;
}
boolean is(final Class type) {
return Set.class.isAssignableFrom(type);
}
}
/**
* Determines if the class represented by this vector is either the
* same as or a supertype of the specified target type.
*/
abstract boolean is(Class type);
}
/**
* Converter map.
*/
private static class ConverterMap extends LinkedHashMap,Converter> {
private static final long serialVersionUID = -1L;
private final Class referenceType, primitiveType;
private ConverterMap(Class referenceType, Class primitiveType) {
this.referenceType = referenceType;
this.primitiveType = primitiveType;
}
private ConverterMap with(Class targetType, Converter converter) {
put(targetType, converter);
return this;
}
private boolean isAssignableFrom(Class type) {
return type.isPrimitive() ? primitiveType == type : referenceType.isAssignableFrom(type);
}
@SuppressWarnings("unchecked")
private Converter getConverter(Class targetType) {
for (final Map.Entry,Converter> entry : entrySet()) {
if (entry.getKey().isAssignableFrom(targetType)) {
return (Converter)entry.getValue();
}
}
if (isAssignableFrom(targetType)) {
return (Converter)ToObject.FromObject;
}
throw new DynamoDBMappingException(
"type [" + targetType + "] is not supported; no conversion from " + referenceType
);
}
}
/**
* {@link BigDecimal} conversion functions.
*/
private static abstract class ToBigDecimal extends Converter {
private static final ToBigDecimal FromString = new ToBigDecimal() {
@Override
public final BigDecimal convert(final String o) {
return new BigDecimal(o);
}
};
}
/**
* {@link BigInteger} conversion functions.
*/
private static abstract class ToBigInteger extends Converter {
private static final ToBigInteger FromString = new ToBigInteger() {
@Override
public final BigInteger convert(final String o) {
return new BigInteger(o);
}
};
}
/**
* {@link Boolean} conversion functions.
*/
private static abstract class ToBoolean extends Converter {
private static final ToBoolean FromString = new ToBoolean() {
private final Pattern N0 = Pattern.compile("(?i)[N0]");
private final Pattern Y1 = Pattern.compile("(?i)[Y1]");
@Override
public final Boolean convert(final String o) {
return N0.matcher(o).matches() ? Boolean.FALSE : Y1.matcher(o).matches() ? Boolean.TRUE : Boolean.valueOf(o);
}
};
}
/**
* {@link Byte} conversion functions.
*/
private static abstract class ToByte extends Converter {
private static final ToByte FromNumber = new ToByte() {
@Override
public final Byte convert(final Number o) {
return o.byteValue();
}
};
private static final ToByte FromString = new ToByte() {
@Override
public final Byte convert(final String o) {
return Byte.valueOf(o);
}
};
}
/**
* {@link byte} array conversion functions.
*/
private static abstract class ToByteArray extends Converter {
private static final ToByteArray FromByteBuffer = new ToByteArray() {
@Override
public final byte[] convert(final ByteBuffer o) {
if (o.hasArray()) {
return o.array();
}
final byte[] value = new byte[o.remaining()];
o.get(value);
return value;
}
};
private static final ToByteArray FromString = new ToByteArray() {
@Override
public final byte[] convert(final String o) {
return o.getBytes(Charset.forName("UTF-8"));
}
};
}
/**
* {@link ByteBuffer} conversion functions.
*/
private static abstract class ToByteBuffer extends Converter {
private static final ToByteBuffer FromByteArray = new ToByteBuffer() {
@Override
public final ByteBuffer convert(final byte[] o) {
return ByteBuffer.wrap(o);
}
};
private static final ToByteBuffer FromUuid = new ToByteBuffer() {
@Override
public final ByteBuffer convert(final java.util.UUID o) {
final ByteBuffer value = ByteBuffer.allocate(16);
value.putLong(o.getMostSignificantBits()).putLong(o.getLeastSignificantBits());
value.position(0);
return value;
}
};
}
/**
* {@link Calendar} conversion functions.
*/
private static abstract class ToCalendar extends Converter {
private static final ToCalendar FromDate = new ToCalendar() {
@Override
public final Calendar convert(final Date o) {
final Calendar value = Calendar.getInstance();
value.setTime(o);
return value;
}
};
}
/**
* {@link Character} conversion functions.
*/
private static abstract class ToCharacter extends Converter {
private static final ToCharacter FromString = new ToCharacter() {
@Override
public final Character convert(final String o) {
return Character.valueOf(o.charAt(0));
}
};
}
/**
* {@link Currency} conversion functions.
*/
private static abstract class ToCurrency extends Converter {
private static final ToCurrency FromString = new ToCurrency() {
@Override
public final Currency convert(final String o) {
return Currency.getInstance(o);
}
};
}
/**
* {@link Date} conversion functions.
*/
private static abstract class ToDate extends Converter {
private static final ToDate FromCalendar = new ToDate() {
@Override
public final Date convert(final Calendar o) {
return o.getTime();
}
};
private static final ToDate FromDateTime = new ToDate() {
@Override
public final Date convert(final DateTime o) {
return o.toDate();
}
};
private static final ToDate FromLong = new ToDate() {
@Override
public final Date convert(final Long o) {
return new Date(o);
}
};
private static final ToDate FromString = new ToDate() {
@Override
public final Date convert(final String o) {
return DateUtils.parseISO8601Date(o);
}
};
}
/**
* {@link DateTime} conversion functions.
*/
private static abstract class ToDateTime extends Converter {
private static final ToDateTime FromDate = new ToDateTime() {
public final DateTime convert(final Date o) {
return new DateTime(o);
}
};
}
/**
* {@link Double} conversion functions.
*/
private static abstract class ToDouble extends Converter {
private static final ToDouble FromNumber = new ToDouble() {
@Override
public final Double convert(final Number o) {
return o.doubleValue();
}
};
private static final ToDouble FromString = new ToDouble() {
@Override
public final Double convert(final String o) {
return Double.valueOf(o);
}
};
}
/**
* {@link Enum} from {@link String}
*/
private static abstract class ToEnum,T> extends Converter {
private static final class FromString> extends ToEnum {
private final Class sourceType;
private FromString(final Class sourceType) {
this.sourceType = sourceType;
}
@Override
public final S convert(final String o) {
return Enum.valueOf(sourceType, o);
}
}
}
/**
* {@link Float} conversion functions.
*/
private static abstract class ToFloat extends Converter {
private static final ToFloat FromNumber = new ToFloat() {
@Override
public final Float convert(final Number o) {
return o.floatValue();
}
};
private static final ToFloat FromString = new ToFloat() {
@Override
public final Float convert(final String o) {
return Float.valueOf(o);
}
};
}
/**
* {@link Integer} conversion functions.
*/
private static abstract class ToInteger extends Converter {
private static final ToInteger FromNumber = new ToInteger() {
@Override
public final Integer convert(final Number o) {
return o.intValue();
}
};
private static final ToInteger FromString = new ToInteger() {
@Override
public final Integer convert(final String o) {
return Integer.valueOf(o);
}
};
}
/**
* {@link Locale} conversion functions.
*/
private static abstract class ToLocale extends Converter {
private static final ToLocale FromString = new ToLocale() {
@Override
public final Locale convert(final String o) {
final String[] value = o.split("-", 3);
if (value.length == 3) return new Locale(value[0], value[1], value[2]);
if (value.length == 2) return new Locale(value[0], value[1]);
return new Locale(value[0]); //JDK7+: return Locale.forLanguageTag(o);
}
};
}
/**
* {@link Long} conversion functions.
*/
private static abstract class ToLong extends Converter {
private static final ToLong FromDate = new ToLong() {
@Override
public final Long convert(final Date o) {
return o.getTime();
}
};
private static final ToLong FromNumber = new ToLong() {
@Override
public final Long convert(final Number o) {
return o.longValue();
}
};
private static final ToLong FromString = new ToLong() {
@Override
public final Long convert(final String o) {
return Long.valueOf(o);
}
};
}
/**
* {@link Short} conversion functions.
*/
private static abstract class ToShort extends Converter {
private static final ToShort FromNumber = new ToShort() {
@Override
public final Short convert(final Number o) {
return o.shortValue();
}
};
private static final ToShort FromString = new ToShort() {
@Override
public final Short convert(final String o) {
return Short.valueOf(o);
}
};
}
/**
* {@link String} conversion functions.
*/
private static abstract class ToString extends Converter {
private static final ToString FromBoolean = new ToString() {
@Override
public final String convert(final Boolean o) {
return Boolean.TRUE.equals(o) ? "1" : "0";
}
};
private static final ToString FromByteArray = new ToString() {
@Override
public final String convert(final byte[] o) {
return new String(o, Charset.forName("UTF-8"));
}
};
private static final ToString FromDate = new ToString() {
@Override
public final String convert(final Date o) {
return DateUtils.formatISO8601Date(o);
}
};
private static final ToString FromEnum = new ToString() {
@Override
public final String convert(final Enum o) {
return o.name();
}
};
private static final ToString FromLocale = new ToString() {
@Override
public final String convert(final Locale o) {
final StringBuilder value = new StringBuilder(o.getLanguage());
if (!o.getCountry().isEmpty() || !o.getVariant().isEmpty()) {
value.append("-").append(o.getCountry());
}
if (!o.getVariant().isEmpty()) {
value.append("-").append(o.getVariant());
}
return value.toString(); //JDK7+: return o.toLanguageTag();
}
};
private static final ToString FromNumber = new ToString() {
@Override
public final String convert(final Number o) {
return o.toString();
}
};
private static final ToString FromTimeZone = new ToString() {
@Override
public final String convert(final TimeZone o) {
return o.getID();
}
};
private static final ToString FromObject = new ToString() {
@Override
public final String convert(final Object o) {
return o.toString();
}
};
}
/**
* {@link TimeZone} conversion functions.
*/
private static abstract class ToTimeZone extends Converter {
private static final ToTimeZone FromString = new ToTimeZone() {
@Override
public final TimeZone convert(final String o) {
return TimeZone.getTimeZone(o);
}
};
}
/**
* {@link java.net.URL} conversion functions.
*/
private static abstract class ToUrl extends Converter {
private static final ToUrl FromString = new ToUrl() {
@Override
public final java.net.URL convert(final String o) {
try {
return new java.net.URL(o);
} catch (final java.net.MalformedURLException e) {
throw new IllegalArgumentException("malformed URL", e);
}
}
};
}
/**
* {@link java.net.URI} conversion functions.
*/
private static abstract class ToUri extends Converter {
private static final ToUri FromString = new ToUri() {
@Override
public final java.net.URI convert(final String o) {
try {
return new java.net.URI(o);
} catch (final java.net.URISyntaxException e) {
throw new IllegalArgumentException("malformed URI", e);
}
}
};
}
/**
* {@link java.util.UUID} conversion functions.
*/
private static abstract class ToUuid extends Converter {
private static final ToUuid FromByteBuffer = new ToUuid() {
@Override
public final java.util.UUID convert(final ByteBuffer o) {
return new java.util.UUID(o.getLong(), o.getLong());
}
};
private static final ToUuid FromString = new ToUuid() {
@Override
public final java.util.UUID convert(final String o) {
return java.util.UUID.fromString(o);
}
};
}
/**
* {@link Object} conversion functions.
*/
private static abstract class ToObject extends Converter {
private static final ToObject FromObject = new ToObject() {
@Override
public final Object convert(final Object o) {
return o;
}
};
}
/**
* One-way type-converter.
*/
static abstract class Converter {
final Converter join(final Converter target) {
final Converter source = this;
return new Converter() {
@Override
public S convert(final U o) {
return source.convert(target.convert(o));
}
};
}
public abstract S convert(T o);
}
}
