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The java.lang.reflect Package
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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()


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