[Chapter 26] 26.3 java.lang.reflect.Field (JDK 1.1)

#

| Chapter 26 The java.lang.reflect Package |

## 26.3 java.lang.reflect.Field (JDK 1.1)

###

This class represents a field of a class. Instances of `Field` are obtained by calling the `getField()` and related methods of `java.lang.Class`. `Field` implements the `Member` interface, so once you have obtained a `Field` object, you can use `getName()`, `getModifiers()`, and `getDeclaringClass()` to determine the name, modifiers, and class of the field. Additionally, `getType()` returns the type of the field.

The `set()` method sets the value of the represented field for a specified object to a given value. (If the represented field is `static`, then no object need be specified for it to be set upon, of course.) If the field is of a primitive type, its value can be specified using a wrapper object of type `Boolean`, `Integer`, and so on, or it can be set using the `setBoolean()`, `setInt()`, and related methods.

Similarly, the `get()` method queries the value of the represented field for a specified object and returns the field value as an `Object`. Various other methods query the field value and return it as various primitive types.

    public final class Field extends Object implements Member {
        // No Constructor
        // Public Instance Methods
                public boolean equals(Object obj);  // Overrides Object
                public native Object get(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native boolean getBoolean(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native byte getByte(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native char getChar(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public Class getDeclaringClass();  // From Member
                public native double getDouble(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native float getFloat(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native int getInt(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native long getLong(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public native int getModifiers();  // From Member
                public String getName();  // From Member
                public native short getShort(Object obj) throws IllegalArgumentException, IllegalAccessException;
                public Class getType();
                public int hashCode();  // Overrides Object
                public native void set(Object obj, Object value) throws IllegalArgumentException, IllegalAccessException;
                public native void setBoolean(Object obj, boolean z) throws IllegalArgumentException, IllegalAccessException;
                public native void setByte(Object obj, byte b) throws IllegalArgumentException, IllegalAccessException;
                public native void setChar(Object obj, char c) throws IllegalArgumentException, IllegalAccessException;
                public native void setDouble(Object obj, double d) throws IllegalArgumentException, IllegalAccessException;
                public native void setFloat(Object obj, float f) throws IllegalArgumentException, IllegalAccessException;
                public native void setInt(Object obj, int i) throws IllegalArgumentException, IllegalAccessException;
                public native void setLong(Object obj, long l) throws IllegalArgumentException, IllegalAccessException;
                public native void setShort(Object obj, short s) throws IllegalArgumentException, IllegalAccessException;
                public String toString();  // Overrides Object
    }

### Returned By:

Class.getDeclaredField(), Class.getDeclaredFields(), Class.getField(), Class.getFields()

java.lang.reflect.Constructor (JDK 1.1) |  | java.lang.reflect.InvocationTargetException (JDK 1.1)