org.springframework.core.convert

接口 ConversionService

所有已知子接口:

ConfigurableConversionService

所有已知实现类:

DefaultConversionService, GenericConversionService

public interface ConversionService

A service interface for type conversion. This is the entry point into the convert system. Call convert(Object, Class) to perform a thread-safe type conversion using this system.

从以下版本开始:

3.0

作者:

Keith Donald, Phillip Webb

方法概要

限定符和类型	方法和说明
boolean	canConvert(Class<?> sourceType, Class<?> targetType) Return true if objects of sourceType can be converted to the targetType.
boolean	canConvert(TypeDescriptor sourceType, TypeDescriptor targetType) Return true if objects of sourceType can be converted to the targetType.
<T> T	convert(Object source, Class<T> targetType) Convert the given source to the specified targetType.
Object	convert(Object source, TypeDescriptor sourceType, TypeDescriptor targetType) Convert the given source to the specified targetType.

方法详细资料

canConvert

boolean canConvert(@Nullable
                   Class<?> sourceType,
                   Class<?> targetType)

Return true if objects of sourceType can be converted to the targetType.

If this method returns true, it means convert(Object, Class) is capable of converting an instance of sourceType to targetType.

Special note on collections, arrays, and maps types: For conversion between collection, array, and map types, this method will return true even though a convert invocation may still generate a ConversionException if the underlying elements are not convertible. Callers are expected to handle this exceptional case when working with collections and maps.

参数:

sourceType - the source type to convert from (may be null if source is null)

targetType - the target type to convert to (required)

返回:

true if a conversion can be performed, false if not

抛出:

IllegalArgumentException - if targetType is null

canConvert

boolean canConvert(@Nullable
                   TypeDescriptor sourceType,
                   TypeDescriptor targetType)

Return true if objects of sourceType can be converted to the targetType. The TypeDescriptors provide additional context about the source and target locations where conversion would occur, often object fields or property locations.

If this method returns true, it means convert(Object, TypeDescriptor, TypeDescriptor) is capable of converting an instance of sourceType to targetType.

Special note on collections, arrays, and maps types: For conversion between collection, array, and map types, this method will return true even though a convert invocation may still generate a ConversionException if the underlying elements are not convertible. Callers are expected to handle this exceptional case when working with collections and maps.

参数:

sourceType - context about the source type to convert from (may be null if source is null)

targetType - context about the target type to convert to (required)

返回:

true if a conversion can be performed between the source and target types, false if not

抛出:

IllegalArgumentException - if targetType is null

convert

@Nullable
<T> T convert(@Nullable
                         Object source,
                         Class<T> targetType)

Convert the given source to the specified targetType.

参数:

source - the source object to convert (may be null)

targetType - the target type to convert to (required)

返回:

the converted object, an instance of targetType

抛出:

ConversionException - if a conversion exception occurred

IllegalArgumentException - if targetType is null

convert

@Nullable
Object convert(@Nullable
                          Object source,
                          @Nullable
                          TypeDescriptor sourceType,
                          TypeDescriptor targetType)

Convert the given source to the specified targetType. The TypeDescriptors provide additional context about the source and target locations where conversion will occur, often object fields or property locations.

参数:

source - the source object to convert (may be null)

sourceType - context about the source type to convert from (may be null if source is null)

targetType - context about the target type to convert to (required)

返回:

the converted object, an instance of targetType

抛出:

ConversionException - if a conversion exception occurred

IllegalArgumentException - if targetType is null, or sourceType is null but source is not null