org.bbottema.javareflection

Class BeanUtils

java.lang.Object

org.bbottema.javareflection.BeanUtils

public final class BeanUtils
extends Object

A Field shorthand utility class used to collect fields from classes meeting Java Bean restrictions/requirements.

With this utility class you can perform field lookups, by combining lookup restriction criteria.

Example
"find all fields on a class Apple, not looking at its super classes, which should be protected, have a getter method, but not a setter method"

 FieldUtils.collectFields(Apple.class, Apple.class, EnumSet.of(Visibility.PROTECTED),
         EnumSet.of(BeanRestriction.YES_GETTER, BeanRestriction.NO_SETTER));
 

See Also:

collectFields(Class, Class, EnumSet, EnumSet)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BeanUtils.BeanRestriction Indicates whether a field needs a Bean setter or getter, exactly none or any combination thereof.
static class	BeanUtils.Visibility Determines what visibility modifiers a field is allowed to have in collectFields(Class, Class, EnumSet, EnumSet).

Constructor Summary

Constructors

Constructor and Description
BeanUtils()

Method Summary

Modifier and Type	Method and Description
static @NotNull LinkedHashMap<Class<?>,List<FieldWrapper>>	collectFields(Class<?> _class, Class<?> boundaryMarker, EnumSet<BeanUtils.Visibility> visibility, EnumSet<BeanUtils.BeanRestriction> beanRestrictions) Returns a pool of Field wrappers including optional relevant setter/getter methods, collected from the given class tested against the given visibility and Bean restriction requirements.
static Object	invokeBeanGetter(Object o, String fieldName) Calls the getter for the first field in the inheritance chain that matches given fieldName.
static @Nullable Object	invokeBeanSetter(Object o, String fieldName, @Nullable Object value) Calls the setter for the first field in the inheritance chain that matches given fieldName.
static boolean	isBeanMethod(Method method, Class<?> boundaryMarker, EnumSet<BeanUtils.Visibility> visibility) Verifies is a given method occurs as setter or getter in the declaring class chain.
static boolean	isBeanMethod(Method method, Class<?> boundaryMarker, EnumSet<BeanUtils.Visibility> visibility, boolean checkBeanLikeForInterfaces)
static boolean	methodIsBeanlike(Method method) Determines if the method could be a bean method by looking just at its name, parameters and presence of return type.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BeanUtils

public BeanUtils()

Method Detail

isBeanMethod

public static boolean isBeanMethod(Method method,
                                   Class<?> boundaryMarker,
                                   EnumSet<BeanUtils.Visibility> visibility)

Verifies is a given method occurs as setter or getter in the declaring class chain. Lookup works by finding actual properties with their respective getters/setters that follow bean convention.

Note that this is a strict lookup and interface methods are not considered bean methods. To include interfaces and their methods, use isBeanMethod(Method, Class, EnumSet, boolean) with checkBeanLikeForInterfaces set to true.

Lookup can be configured to check only against specific visibility.

Parameters:

method - The method to match against getters/setters of a certain visibility

boundaryMarker - The last class or interface implementing class that methods are matched against. Can be used to prevent matching methods on a super class.

visibility - A set of visibility requirements (ie. BeanUtils.Visibility.PROTECTED indicates a *field* for which getter/setter are checked is allowed to have protected visibility). Note: the visibility modifiers for methods are ignored.

Returns:

Whether given method is a setter / getter within given restriction boundaries.

isBeanMethod

public static boolean isBeanMethod(Method method,
                                   Class<?> boundaryMarker,
                                   EnumSet<BeanUtils.Visibility> visibility,
                                   boolean checkBeanLikeForInterfaces)

Returns:

Same as isBeanMethod(Method, Class, EnumSet), but may consider methods declared on interfaces as well.

methodIsBeanlike

public static boolean methodIsBeanlike(Method method)

Determines if the method could be a bean method by looking just at its name, parameters and presence of return type.

Returns:

True, is the method starts with set/get/is, has exactly one parameter and in case of a primitive boolean the method should start with "isAbc"

collectFields

@NotNull
public static @NotNull LinkedHashMap<Class<?>,List<FieldWrapper>> collectFields(Class<?> _class,
                                                                                         Class<?> boundaryMarker,
                                                                                         EnumSet<BeanUtils.Visibility> visibility,
                                                                                         EnumSet<BeanUtils.BeanRestriction> beanRestrictions)

Returns a pool of Field wrappers including optional relevant setter/getter methods, collected from the given class tested against the given visibility and Bean restriction requirements.

The returned fields are mapped against the classes they were found on, since field names can be declared multiple times with the same name.

Parameters:

_class - The class (and chain) to harvest fields from.

boundaryMarker - The last class or interface implementing class that fields are collected from. Can be used to prevent finding fields on a super class.

visibility - A set of visibility requirements (ie. BeanUtils.Visibility.PROTECTED indicates a field is allowed to have protected visibility).

beanRestrictions - A set of Bean restriction requirements indicating a field should or shouldn't have a setter, getter or both.

Returns:

A Map per class in the chain with the fields declared by that class.

See Also:

meetsVisibilityRequirements(Field, EnumSet), resolveBeanProperty(Field, EnumSet)

invokeBeanSetter

@Nullable
public static @Nullable Object invokeBeanSetter(Object o,
                                                          String fieldName,
                                                          @Nullable
                                                          @Nullable Object value)

Calls the setter for the first field in the inheritance chain that matches given fieldName. Attempts to convert the value in case the type is incorrect.

Returns:

The actual value used in the bean setter.

invokeBeanGetter

public static Object invokeBeanGetter(Object o,
                                      String fieldName)

Calls the getter for the first field in the inheritance chain that matches given fieldName.

See Also:

collectFields(Class, Class, EnumSet, EnumSet)