convert system spi and api

org.springframework.core/src/main/java/org/springframework/core/convert/ConversionException.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert;
+
+/**
+ * Base class for exceptions thrown by the convert system.
+ * 
+ * @author Keith Donald
+ */
+public abstract class ConversionException extends RuntimeException {
+
+	/**
+	 * Creates a new conversion exception.
+	 * @param message the exception message
+	 * @param cause the cause
+	 */
+	public ConversionException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	/**
+	 * Creates a new conversion exception.
+	 * @param message the exception message
+	 */
+	public ConversionException(String message) {
+		super(message);
+	}
+}

org.springframework.core/src/main/java/org/springframework/core/convert/ConversionExecutionException.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert;
+
+import org.springframework.core.style.StylerUtils;
+
+/**
+ * Thrown when an attempt to execute a type conversion fails.
+ * 
+ * @author Keith Donald
+ */
+public class ConversionExecutionException extends ConversionException {
+
+	/**
+	 * The value we tried to convert. Transient because we cannot guarantee that the value is Serializable.
+	 */
+	private transient Object value;
+
+	/**
+	 * The source type we tried to convert the value from.
+	 */
+	private Class<?> sourceClass;
+
+	/**
+	 * The target type we tried to convert the value to.
+	 */
+	private Class<?> targetClass;
+
+	/**
+	 * Creates a new conversion exception.
+	 * @param value the value we tried to convert
+	 * @param sourceClass the value's original type
+	 * @param targetClass the value's target type
+	 * @param cause the cause of the conversion failure
+	 */
+	public ConversionExecutionException(Object value, Class<?> sourceClass, Class<?> targetClass, Throwable cause) {
+		super(defaultMessage(value, sourceClass, targetClass, cause), cause);
+		this.value = value;
+		this.sourceClass = sourceClass;
+		this.targetClass = targetClass;
+	}
+
+	/**
+	 * Creates a new conversion exception.
+	 * @param value the value we tried to convert
+	 * @param sourceClass the value's original type
+	 * @param targetClass the value's target type
+	 * @param message a descriptive message of what went wrong.
+	 */
+	public ConversionExecutionException(Object value, Class<?> sourceClass, Class<?> targetClass, String message) {
+		super(message);
+		this.value = value;
+		this.sourceClass = sourceClass;
+		this.targetClass = targetClass;
+	}
+
+	/**
+	 * Returns the actual value we tried to convert, an instance of {@link #getSourceClass()}.
+	 */
+	public Object getValue() {
+		return value;
+	}
+
+	/**
+	 * Returns the source type we tried to convert the value from.
+	 */
+	public Class<?> getSourceClass() {
+		return sourceClass;
+	}
+
+	/**
+	 * Returns the target type we tried to convert the value to.
+	 */
+	public Class<?> getTargetClass() {
+		return targetClass;
+	}
+
+	private static String defaultMessage(Object value, Class<?> sourceClass, Class<?> targetClass, Throwable cause) {
+		return "Unable to convert value " + StylerUtils.style(value) + " from type '" + sourceClass.getName()
+				+ "' to type '" + targetClass.getName() + "'; reason = '" + cause.getMessage() + "'";
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/ConversionExecutor.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert;
+
+/**
+ * A command object that is parameterized with the information necessary to perform a conversion of a source input to a
+ * target output. Encapsulates knowledge about how to convert source objects to a specific target type using a specific
+ * converter.
+ * 
+ * @author Keith Donald
+ */
+public interface ConversionExecutor<S, T> {
+
+	/**
+	 * Returns the source class of conversions performed by this executor.
+	 * @return the source class
+	 */
+	public Class<S> getSourceClass();
+
+	/**
+	 * Returns the target class of conversions performed by this executor.
+	 * @return the target class
+	 */
+	public Class<T> getTargetClass();
+
+	/**
+	 * Execute the conversion for the provided source object.
+	 * @param source the source object to convert
+	 */
+	public T execute(S source) throws ConversionExecutionException;
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/ConversionExecutorNotFoundException.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert;
+
+/**
+ * Thrown when a conversion executor could not be found in a conversion service.
+ * 
+ * @see ConversionService#getConversionExecutor(Class, Class)
+ * @author Keith Donald
+ */
+public class ConversionExecutorNotFoundException extends ConversionException {
+
+	private Class<?> sourceClass;
+
+	private Class<?> targetClass;
+
+	/**
+	 * Creates a new conversion executor not found exception.
+	 * @param sourceClass the source type requested to convert from
+	 * @param targetClass the target type requested to convert to
+	 * @param message a descriptive message
+	 */
+	public ConversionExecutorNotFoundException(Class<?> sourceClass, Class<?> targetClass, String message) {
+		super(message);
+		this.sourceClass = sourceClass;
+		this.targetClass = targetClass;
+	}
+
+	/**
+	 * Returns the source type requested to convert from.
+	 */
+	public Class<?> getSourceClass() {
+		return sourceClass;
+	}
+
+	/**
+	 * Returns the target type requested to convert to.
+	 */
+	public Class<?> getTargetClass() {
+		return targetClass;
+	}
+}

org.springframework.core/src/main/java/org/springframework/core/convert/ConversionService.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert;
+
+/**
+ * A service interface for type conversion. This is the entry point into the convert system. Call one of the
+ * {@link #executeConversion(Object, Class) executeConversion} operations to perform a thread-safe type conversion using
+ * this system. Call one of the {@link #getConversionExecutor(Class, Class) getConversionExecutor} operations to obtain
+ * a thread-safe {@link ConversionExecutor} command for later use.
+ * 
+ * @author Keith Donald
+ */
+public interface ConversionService {
+
+	/**
+	 * Convert the source object to <code>targetClass</code>
+	 * @param source the source to convert from (may be null)
+	 * @param targetClass the target class to convert to
+	 * @return the converted object, an instance of the <code>targetClass</code>, or <code>null</code> if a null source
+	 * was provided
+	 * @throws ConversionExecutorNotFoundException if no suitable conversion executor could be found to convert the
+	 * source to an instance of targetClass
+	 * @throws ConversionException if an exception occurred during the conversion process
+	 */
+	public <T> T executeConversion(Object source, Class<T> targetClass) throws ConversionExecutorNotFoundException,
+			ConversionException;
+
+	/**
+	 * Convert the source object to <code>targetClass</code> using a custom converter.
+	 * @param converterId the id of the custom converter, which must be registered with this conversion service and
+	 * capable of converting to the targetClass
+	 * @param source the source to convert from (may be null)
+	 * @param targetClass the target class to convert to
+	 * @return the converted object, an instance of the <code>targetClass</code>, or <code>null</code> if a null source
+	 * was provided
+	 * @throws ConversionExecutorNotFoundException if no suitable conversion executor could be found to convert the
+	 * source to an instance of targetClass
+	 * @throws ConversionException if an exception occurred during the conversion process
+	 */
+	public <T> T executeConversion(String converterId, Object source, Class<T> targetClass)
+			throws ConversionExecutorNotFoundException, ConversionException;
+
+	/**
+	 * Get a ConversionExecutor capable of converting objects from <code>sourceClass</code> to <code>targetClass</code>.
+	 * The returned ConversionExecutor is thread-safe and may safely be cached for later use by client code.
+	 * @param sourceClass the source class to convert from (required)
+	 * @param targetClass the target class to convert to (required)
+	 * @return the executor that can execute instance type conversion, never null
+	 * @throws ConversionExecutorNotFoundException when no suitable conversion executor could be found
+	 */
+	public <S, T> ConversionExecutor<S, T> getConversionExecutor(Class<S> sourceClass, Class<T> targetClass)
+			throws ConversionExecutorNotFoundException;
+
+	/**
+	 * Get a ConversionExecutor that uses a custom converter to capable convert objects from <code>sourceClass</code> to
+	 * <code>targetClass</code>. The returned ConversionExecutor is thread-safe and may safely be cached for use in
+	 * client code.
+	 * @param converterId the id of the custom converter, which must be registered with this conversion service and
+	 * capable of converting from sourceClass to targetClass (required)
+	 * @param sourceClass the source class to convert from (required)
+	 * @param targetClass the target class to convert to (required)
+	 * @return the executor that can execute instance type conversion, never null
+	 * @throws ConversionExecutorNotFoundException when no suitable conversion executor could be found
+	 */
+	public <S, T> ConversionExecutor<S, T> getConversionExecutor(String converterId, Class<S> sourceClass,
+			Class<T> targetClass) throws ConversionExecutorNotFoundException;
+
+	/**
+	 * Lookup a class by its well-known alias. For example, <code>long</code> for <code>java.lang.Long</code>
+	 * @param alias the class alias
+	 * @return the class, or <code>null</code> if no alias exists
+	 */
+	public Class<?> getClassForAlias(String alias);
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/Converter.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import org.springframework.core.convert.ConversionException;
+import org.springframework.core.convert.ConversionService;
+
+/**
+ * A converter converts a source object of type S to a target type of type T and back.
+ * <p>
+ * Implementations of this interface are thread-safe and can be shared. Converters are typically registered with and
+ * accessed through a {@link ConversionService}.
+ * </p>
+ * @author Keith Donald
+ */
+public interface Converter<S, T> {
+
+	/**
+	 * Convert the source S to target type T.
+	 * @param source the source object to convert, which must be an instance of S
+	 * @return the converted object, which must be an instance of T
+	 * @throws Exception an exception occurred performing the conversion; may be any checked exception, the conversion
+	 * system will handle wrapping the failure in a {@link ConversionException} that provides a consistent type
+	 * conversion error context
+	 */
+	public T convert(S source) throws Exception;
+
+	/**
+	 * Convert the target T back to source type S.
+	 * @param target the target object to convert, which must be an instance of T
+	 * @return the converted object, which must be an instance of S
+	 * @throws Exception an exception occurred performing the conversion; may be any checked exception, the conversion
+	 * system will handle wrapping the failure in a {@link ConversionException} that provides a consistent type
+	 * conversion error context
+	 */
+	public S convertBack(T target) throws Exception;
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/NumberToNumber.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import org.springframework.util.NumberUtils;
+
+/**
+ *Converts from any JDK-standard Number implementation to any other JDK-standard Number implementation.
+ * 
+ * Support Number classes include byte, short, integer, float, double, long, big integer, big decimal. This class
+ * delegates to {@link NumberUtils#convertNumberToTargetClass(Number, Class)} to perform the conversion.
+ * 
+ * @see java.lang.Byte
+ * @see java.lang.Short
+ * @see java.lang.Integer
+ * @see java.lang.Long
+ * @see java.math.BigInteger
+ * @see java.lang.Float
+ * @see java.lang.Double
+ * @see java.math.BigDecimal
+ * 
+ * @author Keith Donald
+ */
+public class NumberToNumber implements SuperConverter<Number, Number> {
+
+	public <N extends Number> N convert(Number source, Class<N> targetClass) throws Exception {
+		return NumberUtils.convertNumberToTargetClass(source, targetClass);
+	}
+
+	public Number convertBack(Number target) throws Exception {
+		return target;
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToBigDecimal.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import java.math.BigDecimal;
+
+/**
+ * Converts a String to a BigDecimal and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToBigDecimal implements Converter<String, BigDecimal> {
+
+	public BigDecimal convert(String source) throws Exception {
+		return new BigDecimal(source);
+	}
+
+	public String convertBack(BigDecimal target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToBigInteger.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import java.math.BigInteger;
+
+/**
+ * Converts a String to a BigInteger and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToBigInteger implements Converter<String, BigInteger> {
+
+	public BigInteger convert(String source) throws Exception {
+		return new BigInteger(source);
+	}
+
+	public String convertBack(BigInteger target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToBoolean.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts String to a Boolean and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToBoolean implements Converter<String, Boolean> {
+
+	private static final String VALUE_TRUE = "true";
+
+	private static final String VALUE_FALSE = "false";
+
+	private String trueString;
+
+	private String falseString;
+
+	/**
+	 * Create a StringToBoolean converter.
+	 */
+	public StringToBoolean() {
+	}
+
+	/**
+	 * Create a StringToBoolean converter configured with specific values for true and false strings.
+	 * @param trueString special true string to use
+	 * @param falseString special false string to use
+	 */
+	public StringToBoolean(String trueString, String falseString) {
+		this.trueString = trueString;
+		this.falseString = falseString;
+	}
+
+	public Boolean convert(String source) throws Exception {
+		if (trueString != null && source.equals(trueString)) {
+			return Boolean.TRUE;
+		} else if (falseString != null && source.equals(falseString)) {
+			return Boolean.FALSE;
+		} else if (trueString == null && source.equals(VALUE_TRUE)) {
+			return Boolean.TRUE;
+		} else if (falseString == null && source.equals(VALUE_FALSE)) {
+			return Boolean.FALSE;
+		} else {
+			throw new IllegalArgumentException("Invalid boolean value [" + source + "]");
+		}
+	}
+
+	public String convertBack(Boolean target) throws Exception {
+		if (Boolean.TRUE.equals(target)) {
+			if (trueString != null) {
+				return trueString;
+			} else {
+				return VALUE_TRUE;
+			}
+		} else if (Boolean.FALSE.equals(target)) {
+			if (falseString != null) {
+				return falseString;
+			} else {
+				return VALUE_FALSE;
+			}
+		} else {
+			throw new IllegalArgumentException("Invalid boolean value [" + target + "]");
+		}
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToByte.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to a Byte and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToByte implements Converter<String, Byte> {
+
+	public Byte convert(String source) throws Exception {
+		return new Byte(source);
+	}
+
+	public String convertBack(Byte target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToCharacter.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to a Character and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToCharacter implements Converter<String, Character> {
+
+	public Character convert(String source) throws Exception {
+		if (source.length() > 1) {
+			throw new IllegalArgumentException("To be a Character the String '" + source + "' must have a length of 1");
+		}
+		return new Character(source.charAt(0));
+	}
+
+	public String convertBack(Character target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToDouble.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to a Double and back.
+ * 
+ * @author Keith Donald
+ */
+public class StringToDouble implements Converter<String, Double> {
+
+	public Double convert(String source) throws Exception {
+		return Double.valueOf(source);
+	}
+
+	public String convertBack(Double target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToEnum.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts from a String to Enum and back.
+ * 
+ * @author Scott Andrews
+ */
+@SuppressWarnings("unchecked")
+public class StringToEnum implements SuperConverter<String, Enum> {
+
+	public <E extends Enum> E convert(String source, Class<E> targetClass) throws Exception {
+		return Enum.valueOf(targetClass, source);
+	}
+
+	public String convertBack(Enum target) throws Exception {
+		return target.name();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToFloat.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to an Short using {@link Short#valueOf(String)}.
+ * 
+ * @author Keith Donald
+ */
+public class StringToFloat implements Converter<String, Float> {
+
+	public Float convert(String source) throws Exception {
+		return Float.valueOf(source);
+	}
+
+	public String convertBack(Float target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToInteger.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to an Integer using {@link Integer#valueOf(String)}.
+ * 
+ * @author Keith Donald
+ */
+public class StringToInteger implements Converter<String, Integer> {
+
+	public Integer convert(String source) throws Exception {
+		return Integer.valueOf(source);
+	}
+
+	public String convertBack(Integer target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToLocale.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import java.util.Locale;
+
+import org.springframework.util.StringUtils;
+
+/**
+ * Converts a String to a Locale using {@link StringUtils#parseLocaleString(String)}.
+ * 
+ * @author Keith Donald
+ */
+public class StringToLocale implements Converter<String, Locale> {
+
+	public Locale convert(String source) throws Exception {
+		return StringUtils.parseLocaleString(source);
+	}
+
+	public String convertBack(Locale target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToLong.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to an Long using {@link Long#valueOf(String)}.
+ * 
+ * @author Keith Donald
+ */
+public class StringToLong implements Converter<String, Long> {
+
+	public Long convert(String source) throws Exception {
+		return Long.valueOf(source);
+	}
+
+	public String convertBack(Long target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/StringToShort.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+/**
+ * Converts a String to an Short using {@link Short#valueOf(String)}.
+ * 
+ * @author Keith Donald
+ */
+public class StringToShort implements Converter<String, Short> {
+
+	public Short convert(String source) throws Exception {
+		return Short.valueOf(source);
+	}
+
+	public String convertBack(Short target) throws Exception {
+		return target.toString();
+	}
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/SuperConverter.java

+/*
+ * Copyright 2004-2009 the original author or authors.
+ * 
+ * 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://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.springframework.core.convert.converter;
+
+import org.springframework.core.convert.ConversionException;
+import org.springframework.core.convert.ConversionService;
+
+/**
+ * A super converter converts a source object of type S to a target type of type AT and back, where AT is equal to or a
+ * subclass of T.
+ * <p>
+ * Implementations of this interface are thread-safe and can be shared. Converters are typically registered with and
+ * accessed through a {@link ConversionService}.
+ * </p>
+ * @author Keith Donald
+ */
+public interface SuperConverter<S, T> {
+
+	/**
+	 * Convert the source S to an instance of AT.
+	 * @param source the source object to convert, which must be an instance of S
+	 * @param actualTargetClass the actual target class to convert to (AT), which must be equal to or a specialization
+	 * of T.
+	 * @return the converted object, which must be an instance of AT
+	 * @throws Exception an exception occurred performing the conversion; may be any checked exception, the conversion
+	 * system will handle wrapping the failure in a {@link ConversionException} that provides a consistent type
+	 * conversion error context
+	 */
+	public <AT extends T> AT convert(S source, Class<AT> actualTargetClass) throws Exception;
+
+	/**
+	 * Convert the target T to an instance of S.
+	 * @param target the target object to convert, which must be an instance of T.
+	 * @return the converted object, which must be an instance of S.
+	 * @throws Exception an exception occurred performing the conversion; may be any checked exception, the conversion
+	 * system will handle wrapping the failure in a {@link ConversionException} that provides a consistent type
+	 * conversion error context
+	 */
+	public S convertBack(T target) throws Exception;
+
+}
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/converter/package.html

+<html>
+<body>
+<p>
+User Converter API and default Converter implementations.
+</p>
+</body>
+</html>
\ No newline at end of file

org.springframework.core/src/main/java/org/springframework/core/convert/package.html

+<html>
+<body>
+<p>
+Type conversion system SPI.
+</p>
+</body>
+</html>
\ No newline at end of file