diff --git a/spring-core/src/main/java/org/springframework/core/convert/support/FallbackObjectToStringConverter.java b/spring-core/src/main/java/org/springframework/core/convert/support/FallbackObjectToStringConverter.java index 7de6d62578..a876760af1 100644 --- a/spring-core/src/main/java/org/springframework/core/convert/support/FallbackObjectToStringConverter.java +++ b/spring-core/src/main/java/org/springframework/core/convert/support/FallbackObjectToStringConverter.java @@ -22,7 +22,6 @@ import java.util.Set; import org.springframework.core.convert.TypeDescriptor; import org.springframework.core.convert.converter.ConditionalGenericConverter; -import org.springframework.util.ClassUtils; /** * Simply calls {@link Object#toString()} to convert any supported object @@ -37,7 +36,9 @@ import org.springframework.util.ClassUtils; * * @author Keith Donald * @author Juergen Hoeller + * @author Sam Brannen * @since 3.0 + * @see ObjectToObjectConverter */ final class FallbackObjectToStringConverter implements ConditionalGenericConverter { @@ -50,12 +51,13 @@ final class FallbackObjectToStringConverter implements ConditionalGenericConvert public boolean matches(TypeDescriptor sourceType, TypeDescriptor targetType) { Class> sourceClass = sourceType.getObjectType(); if (String.class.equals(sourceClass)) { + // no conversion required return false; } return (CharSequence.class.isAssignableFrom(sourceClass) || StringWriter.class.isAssignableFrom(sourceClass) || - ObjectToObjectConverter.getOfMethod(sourceClass, String.class) != null || - ClassUtils.getConstructorIfAvailable(sourceClass, String.class) != null); + ObjectToObjectConverter.hasFactoryMethod(sourceClass, String.class) || + ObjectToObjectConverter.hasFactoryConstructor(sourceClass, String.class)); } @Override diff --git a/spring-core/src/main/java/org/springframework/core/convert/support/ObjectToObjectConverter.java b/spring-core/src/main/java/org/springframework/core/convert/support/ObjectToObjectConverter.java index 7b83374fa0..609cbae59e 100644 --- a/spring-core/src/main/java/org/springframework/core/convert/support/ObjectToObjectConverter.java +++ b/spring-core/src/main/java/org/springframework/core/convert/support/ObjectToObjectConverter.java @@ -47,9 +47,16 @@ import org.springframework.util.ReflectionUtils; *
Warning: this converter does not support the + * {@link Object#toString()} method for converting from a {@code sourceType} + * to {@code java.lang.String}. For {@code toString()} support, use + * {@link FallbackObjectToStringConverter} instead. + * * @author Keith Donald * @author Juergen Hoeller + * @author Sam Brannen * @since 3.0 + * @see FallbackObjectToStringConverter */ final class ObjectToObjectConverter implements ConditionalGenericConverter { @@ -65,8 +72,8 @@ final class ObjectToObjectConverter implements ConditionalGenericConverter { return false; } return (String.class.equals(targetType.getType()) ? - (ClassUtils.getConstructorIfAvailable(String.class, sourceType.getType()) != null) : - hasToMethodOrOfMethodOrConstructor(targetType.getType(), sourceType.getType())); + hasFactoryConstructor(String.class, sourceType.getType()) : + hasToMethodOrFactoryMethodOrConstructor(targetType.getType(), sourceType.getType())); } @Override @@ -77,19 +84,22 @@ final class ObjectToObjectConverter implements ConditionalGenericConverter { Class> sourceClass = sourceType.getType(); Class> targetClass = targetType.getType(); try { + // Do not invoke a toString() method if (!String.class.equals(targetClass)) { Method method = getToMethod(targetClass, sourceClass); if (method != null) { ReflectionUtils.makeAccessible(method); return method.invoke(source); } - method = getOfMethod(targetClass, sourceClass); - if (method != null) { - ReflectionUtils.makeAccessible(method); - return method.invoke(null, source); - } } - Constructor> constructor = ClassUtils.getConstructorIfAvailable(targetClass, sourceClass); + + Method method = getFactoryMethod(targetClass, sourceClass); + if (method != null) { + ReflectionUtils.makeAccessible(method); + return method.invoke(null, source); + } + + Constructor> constructor = getFactoryConstructor(targetClass, sourceClass); if (constructor != null) { return constructor.newInstance(source); } @@ -100,23 +110,26 @@ final class ObjectToObjectConverter implements ConditionalGenericConverter { catch (Throwable ex) { throw new ConversionFailedException(sourceType, targetType, source, ex); } - throw new IllegalStateException("No static valueOf/of/from(" + sourceClass.getName() + - ") method or Constructor(" + sourceClass.getName() + ") exists on " + targetClass.getName()); + + // If sourceClass is Number and targetClass is Integer, then the following message + // format should expand to: + // No toInteger() method exists on java.lang.Number, and no static + // valueOf/of/from(java.lang.Number) method or Integer(java.lang.Number) + // constructor exists on java.lang.Integer. + String message = String.format( + "No to%3$s() method exists on %1$s, and no static valueOf/of/from(%1$s) method or %3$s(%1$s) constructor exists on %2$s.", + sourceClass.getName(), targetClass.getName(), targetClass.getSimpleName()); + + throw new IllegalStateException(message); } - private static boolean hasToMethodOrOfMethodOrConstructor(Class> targetClass, Class> sourceClass) { - return (getToMethod(targetClass, sourceClass) != null || - getOfMethod(targetClass, sourceClass) != null || - ClassUtils.getConstructorIfAvailable(targetClass, sourceClass) != null); - } - private static Method getToMethod(Class> targetClass, Class> sourceClass) { Method method = ClassUtils.getMethodIfAvailable(sourceClass, "to" + targetClass.getSimpleName()); return (method != null && targetClass.equals(method.getReturnType()) ? method : null); } - static Method getOfMethod(Class> targetClass, Class> sourceClass) { + private static Method getFactoryMethod(Class> targetClass, Class> sourceClass) { Method method = ClassUtils.getStaticMethod(targetClass, "valueOf", sourceClass); if (method == null) { method = ClassUtils.getStaticMethod(targetClass, "of", sourceClass); @@ -127,4 +140,27 @@ final class ObjectToObjectConverter implements ConditionalGenericConverter { return method; } + private static Constructor> getFactoryConstructor(Class> targetClass, Class> sourceClass) { + return ClassUtils.getConstructorIfAvailable(targetClass, sourceClass); + } + + private static boolean hasToMethodOrFactoryMethodOrConstructor(Class> targetClass, + Class> sourceClass) { + return (hasToMethod(targetClass, sourceClass) || + hasFactoryMethod(targetClass, sourceClass) || + hasFactoryConstructor(targetClass, sourceClass)); + } + + static boolean hasToMethod(Class> targetClass, Class> sourceClass) { + return getToMethod(targetClass, sourceClass) != null; + } + + static boolean hasFactoryMethod(Class> targetClass, Class> sourceClass) { + return getFactoryMethod(targetClass, sourceClass) != null; + } + + static boolean hasFactoryConstructor(Class> targetClass, Class> sourceClass) { + return getFactoryConstructor(targetClass, sourceClass) != null; + } + }