Java Field from Class getField(final Class javaClass, final String fieldName, final boolean shouldSetAccessible)

Description

Get a field in a class or its superclasses and wrap the call in doPrivileged if necessary.

License

Open Source License

Parameter

Parameter	Description
javaClass	The class to get the field from
fieldName	The name of the field
shouldSetAccessible	whether or not to call the setAccessible API

Exception

Parameter	Description

Declaration

public static Field getField(final Class javaClass, final String fieldName, final boolean shouldSetAccessible)
        throws NoSuchFieldException 

Method Source Code

//package com.java2s;
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import java.lang.reflect.*;

public class Main {
    /**
     * Get a field in a class or its superclasses and wrap the call in doPrivileged if necessary.
     * The shouldSetAccessible parameter allows the the setAccessible API to be called as well.
     * This option was added to avoid making multiple doPrivileged calls within InstanceVariableAttributeAccessor.
     * @param javaClass The class to get the field from
     * @param fieldName The name of the field
     * @param shouldSetAccessible whether or not to call the setAccessible API
     * @throws java.lang.NoSuchFieldException
     */
    public static Field getField(final Class javaClass, final String fieldName, final boolean shouldSetAccessible)
            throws NoSuchFieldException {
        Field field = (Field) findDeclaredField(javaClass, fieldName);
        if (shouldSetAccessible) {
            field.setAccessible(true);
        }
        return field;
    }

    /**
     * Finding a field within a class potentially has to navigate through it's superclasses to eventually
     * find the field.  This method is called by the public getDeclaredField() method and does a recursive
     * search for the named field in the given classes or it's superclasses.
     */
    private static Field findDeclaredField(Class javaClass, String fieldName) throws NoSuchFieldException {
        try {
            return javaClass.getDeclaredField(fieldName);
        } catch (NoSuchFieldException ex) {
            Class superclass = javaClass.getSuperclass();
            if (superclass == null) {
                throw ex;
            } else {
                return findDeclaredField(superclass, fieldName);
            }
        }
    }

    /**
     * Get a field actually declared in a class and wrap the call in doPrivileged if necessary.
     * The shouldSetAccessible parameter allows the the setAccessible API to be called as well.
     * This option was added to avoid making multiple doPrivileged calls within InstanceVariableAttributeAccessor.
     * @param javaClass The class to get the field from
     * @param fieldName The name of the field
     * @param shouldSetAccessible whether or not to call the setAccessible API
     * @throws java.lang.NoSuchFieldException
     */
    public static Field getDeclaredField(final Class javaClass, final String fieldName,
            final boolean shouldSetAccessible) throws NoSuchFieldException {
        Field field = javaClass.getDeclaredField(fieldName);
        if (shouldSetAccessible) {
            field.setAccessible(true);
        }
        return field;
    }
}

Related

1. findDeclaredField(Class javaClass, String fieldName)
2. getDeclaredField(final Class javaClass, final String fieldName, final boolean shouldSetAccessible)
3. getDeclaredFields(final Class clazz)
4. getField(Class type, String name)
5. getJsonValueFieldName(String className)
6. getProperField(Class objectClass)
7. setPrivateField(String fieldName, Class containingClass, Object target, Object value)