https://openjdk.java.net/ 
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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package com.sun.jdi;


A class or instance variable in the target VM. See TypeComponent for general information about Field and Method mirrors. 
Author:Robert Field, Gordon Hirsch, James McIlree
See Also:
Since: 1.3
/**
 * A class or instance variable in the target VM.
 * See {@link TypeComponent}
 * for general information about Field and Method mirrors.
 *
 * @see ObjectReference
 * @see ReferenceType
 *
 * @author Robert Field
 * @author Gordon Hirsch
 * @author James McIlree
 * @since  1.3
 */
@jdk.Exported
public interface Field extends TypeComponent, Comparable<Field> {

    
Returns a text representation of the type
of this field.
Where the type is the type specified in the declaration
of this field.


This type name is always available even if
the type has not yet been created or loaded.

Returns:a String representing the
type of this field.
/**
     * Returns a text representation of the type
     * of this field.
     * Where the type is the type specified in the declaration
     * of this field.
     * <P>
     * This type name is always available even if
     * the type has not yet been created or loaded.
     *
     * @return a String representing the
     * type of this field.
     */
    String typeName();

    
Returns the type of this field.
Where the type is the type specified in the declaration
of this field.


For example, if a target class defines:

   short s;
   Date d;
   byte[] ba;

And the JDI client defines these Field objects:

   Field sField = targetClass.fieldByName("s");
   Field dField = targetClass.fieldByName("d");
   Field baField = targetClass.fieldByName("ba");

to mirror the corresponding fields, then sField.type() is a ShortType, dField.type() is the ReferenceType for java.util.Date and
((ArrayType)(baField.type())).componentType() is a ByteType. 
 Note: if the type of this field is a reference type (class, interface, or array) and it has not been created or loaded by the declaring type's class loader - that is, declaringType() .classLoader(), then ClassNotLoadedException will be thrown. Also, a reference type may have been loaded but not yet prepared, in which case the type will be returned but attempts to perform some operations on the returned type (e.g. fields()) will throw a ClassNotPreparedException. Use ReferenceType.isPrepared() to determine if a reference type is prepared. 
Throws:
See Also:
Returns:the Type of this field.
/**
     * Returns the type of this field.
     * Where the type is the type specified in the declaration
     * of this field.
     * <P>
     * For example, if a target class defines:
     * <PRE>
     *    short s;
     *    Date d;
     *    byte[] ba;</PRE>
     * And the JDI client defines these <CODE>Field</CODE> objects:
     * <PRE>
     *    Field sField = targetClass.fieldByName("s");
     *    Field dField = targetClass.fieldByName("d");
     *    Field baField = targetClass.fieldByName("ba");</PRE>
     * to mirror the corresponding fields, then <CODE>sField.type()</CODE>
     * is a {@link ShortType}, <CODE>dField.type()</CODE> is the
     * {@link ReferenceType} for <CODE>java.util.Date</CODE> and
     * <CODE>((ArrayType)(baField.type())).componentType()</CODE> is a
     * {@link ByteType}.
     * <P>
     * Note: if the type of this field is a reference type (class,
     * interface, or array) and it has not been created or loaded
     * by the declaring type's class loader - that is,
     * {@link TypeComponent#declaringType <CODE>declaringType()</CODE>}
     * <CODE>.classLoader()</CODE>,
     * then ClassNotLoadedException will be thrown.
     * Also, a reference type may have been loaded but not yet prepared,
     * in which case the type will be returned
     * but attempts to perform some operations on the returned type
     * (e.g. {@link ReferenceType#fields() fields()}) will throw
     * a {@link ClassNotPreparedException}.
     * Use {@link ReferenceType#isPrepared()} to determine if
     * a reference type is prepared.
     *
     * @see Type
     * @return the {@link Type} of this field.
     * @throws ClassNotLoadedException if the type has not yet been loaded
     * or created through the appropriate class loader.
     */
    Type type() throws ClassNotLoadedException;

    
Determine if this is a transient field.

Returns:true if this field is transient; false otherwise.
/**
     * Determine if this is a transient field.
     *
     * @return <code>true</code> if this field is transient; false otherwise.
     */
    boolean isTransient();

    
Determine if this is a volatile field.

Returns:true if this field is volatile; false otherwise.
/**
     * Determine if this is a volatile field.
     *
     * @return <code>true</code> if this field is volatile; false otherwise.
     */
    boolean isVolatile();

    
Determine if this is a field that represents an enum constant.

Returns:true if this field represents an enum constant;
false otherwise.
/**
     * Determine if this is a field that represents an enum constant.
     * @return <code>true</code> if this field represents an enum constant;
     * false otherwise.
     */
    boolean isEnumConstant();

    
Compares the specified Object with this field for equality.

Returns:true if the Object is a Field and if both
mirror the same field (declared in the same class or interface, in
the same VM).
/**
     * Compares the specified Object with this field for equality.
     *
     * @return true if the Object is a Field and if both
     * mirror the same field (declared in the same class or interface, in
     * the same VM).
     */
    boolean equals(Object obj);

    
Returns the hash code value for this Field.

Returns:the integer hash code
/**
     * Returns the hash code value for this Field.
     *
     * @return the integer hash code
     */
    int hashCode();
}