All Known Subinterfaces:
ConfigurableEnvironment, ConfigurablePropertyResolver, ConfigurableWebEnvironment, Environment
All Known Implementing Classes:
AbstractEnvironment, AbstractPropertyResolver, MockEnvironment, PropertySourcesPropertyResolver, StandardEnvironment, StandardServletEnvironment
```
public interface PropertyResolver
```
Interface for resolving properties against any underlying source.
Since:
3.1
Author:
Chris Beams, Juergen Hoeller
See Also:
Environment, PropertySourcesPropertyResolver

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`containsProperty(String key)`	Return whether the given property key is available for resolution, i.e.
`String`	`getProperty(String key)`	Return the property value associated with the given key, or `null` if the key cannot be resolved.
`<T> T`	`getProperty(String key, Class<T> targetType)`	Return the property value associated with the given key, or `null` if the key cannot be resolved.
`<T> T`	`getProperty(String key, Class<T> targetType, T defaultValue)`	Return the property value associated with the given key, or `defaultValue` if the key cannot be resolved.
`String`	`getProperty(String key, String defaultValue)`	Return the property value associated with the given key, or `defaultValue` if the key cannot be resolved.
`String`	`getRequiredProperty(String key)`	Return the property value associated with the given key (never `null`).
`<T> T`	`getRequiredProperty(String key, Class<T> targetType)`	Return the property value associated with the given key, converted to the given targetType (never `null`).
`String`	`resolvePlaceholders(String text)`	Resolve ${...} placeholders in the given text, replacing them with corresponding property values as resolved by `getProperty(java.lang.String)`.
`String`	`resolveRequiredPlaceholders(String text)`	Resolve ${...} placeholders in the given text, replacing them with corresponding property values as resolved by `getProperty(java.lang.String)`.

- Method Detail
  - containsProperty
```
boolean containsProperty(String key)
```
    Return whether the given property key is available for resolution, i.e. if the value for the given key is not null.
  - getProperty
```
@Nullable
String getProperty(String key)
```
    Return the property value associated with the given key, or null if the key cannot be resolved.
    Parameters:
    key - the property name to resolve
    See Also:
    getProperty(String, String), getProperty(String, Class), getRequiredProperty(String)
  - getProperty
```
String getProperty(String key,
                   String defaultValue)
```
    Return the property value associated with the given key, or defaultValue if the key cannot be resolved.
    Parameters:
    key - the property name to resolve
    defaultValue - the default value to return if no value is found
    See Also:
    getRequiredProperty(String), getProperty(String, Class)
  - getProperty
```
@Nullable
<T> T getProperty(String key,
                  Class<T> targetType)
```
    Return the property value associated with the given key, or null if the key cannot be resolved.
    Parameters:
    key - the property name to resolve
    targetType - the expected type of the property value
    See Also:
    getRequiredProperty(String, Class)
  - getProperty
```
<T> T getProperty(String key,
                  Class<T> targetType,
                  T defaultValue)
```
    Return the property value associated with the given key, or defaultValue if the key cannot be resolved.
    Parameters:
    key - the property name to resolve
    targetType - the expected type of the property value
    defaultValue - the default value to return if no value is found
    See Also:
    getRequiredProperty(String, Class)
  - getRequiredProperty
```
String getRequiredProperty(String key)
                    throws IllegalStateException
```
    Return the property value associated with the given key (never null).
    Throws:
    IllegalStateException - if the key cannot be resolved
    See Also:
    getRequiredProperty(String, Class)
  - getRequiredProperty
```
<T> T getRequiredProperty(String key,
                          Class<T> targetType)
                   throws IllegalStateException
```
    Return the property value associated with the given key, converted to the given targetType (never null).
    Throws:
    IllegalStateException - if the given key cannot be resolved
  - resolvePlaceholders
```
String resolvePlaceholders(String text)
```
    Resolve ${...} placeholders in the given text, replacing them with corresponding property values as resolved by getProperty(java.lang.String). Unresolvable placeholders with no default value are ignored and passed through unchanged.
    Parameters:
    text - the String to resolve
    Returns:
    the resolved String (never null)
    Throws:
    IllegalArgumentException - if given text is null
    See Also:
    resolveRequiredPlaceholders(java.lang.String)
  - resolveRequiredPlaceholders
```
String resolveRequiredPlaceholders(String text)
                            throws IllegalArgumentException
```
    Resolve ${...} placeholders in the given text, replacing them with corresponding property values as resolved by getProperty(java.lang.String). Unresolvable placeholders with no default value will cause an IllegalArgumentException to be thrown.
    Returns:
    the resolved String (never null)
    Throws:
    IllegalArgumentException - if given text is null or if any placeholders are unresolvable

Interface PropertyResolver

Method Summary

Method Detail

containsProperty

getProperty

getProperty

getProperty

getProperty

getRequiredProperty

getRequiredProperty

resolvePlaceholders

resolveRequiredPlaceholders