Constant

java.lang.Object
- polyglot.types.reflect.Constant

```
public class Constant
extends java.lang.Object
```
A Constant is used to represent an item in the constant pool of a class.

Author:

Nate Nystrom (nystrom@cs.purdue.edu)

Field Summary

Fields
Modifier and Type	Field and Description
`static byte`	`CLASS` Constant tag for class types.
`static byte`	`DOUBLE` Constant tag for double constants.
`static byte`	`FIELD_REF` Constant tag for field references.
`static byte`	`FLOAT` Constant tag for float constants.
`static byte`	`INTEGER` Constant tag for int, short, byte, char, and boolean constants.
`static byte`	`INTERFACE_METHOD_REF` Constant tag for method references.
`static byte`	`INVOKE_DYNAMIC` Constant tag for holding a bootstrap method.
`static byte`	`LONG` Constant tag for long constants.
`static byte`	`METHOD_HANDLE` Constant tag for holding a method handle.
`static byte`	`METHOD_REF` Constant tag for method references.
`static byte`	`METHOD_TYPE` Constant tag for holding a method type.
`static byte`	`NAME_AND_TYPE` Constant tag for holding the name and type of a field or method.
`static byte`	`STRING` Constant tag for java.lang.String constants.
`protected int`	`tag`
`static byte`	`UTF8` Constant tag for holding a UTF8 format string.
`protected java.lang.Object`	`value`

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`equals(java.lang.Object other)` Check if an object is equal to this constant.
`int`	`hashCode()` Hash the constant.
`int`	`tag()` Get the tag of the constant.
`java.lang.Object`	`value()` Get the value of the constant.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - tag
```
protected int tag
```
  - value
```
protected java.lang.Object value
```
  - CLASS
```
public static final byte CLASS
```
    Constant tag for class types. This is used to reference other classes, such as the superclass, and is used by the checkcast and instanceof instructions. The Fieldref, Methodref and InterfaceMethodref constant types refer to this constant type.
    
    See Also:
    Constant Field Values
  - FIELD_REF
```
public static final byte FIELD_REF
```
    Constant tag for field references. This is used to reference a field in (possibly) another class. The getfield, putfield, getstatic, and putstatic instructions use this constant type.
    
    See Also:
    Constant Field Values
  - METHOD_REF
```
public static final byte METHOD_REF
```
    Constant tag for method references. This is used to reference a method in (possibly) another class. The invokevirtual, invokespecial, and invokestatic instructions use this constant type.
    
    See Also:
    Constant Field Values
  - STRING
```
public static final byte STRING
```
    Constant tag for java.lang.String constants. The actual string value is stored indirectly in a Utf8 constant.
    
    See Also:
    Constant Field Values
  - INTEGER
```
public static final byte INTEGER
```
    Constant tag for int, short, byte, char, and boolean constants.
    
    See Also:
    Constant Field Values
  - FLOAT
```
public static final byte FLOAT
```
    Constant tag for float constants.
    
    See Also:
    Constant Field Values
  - LONG
```
public static final byte LONG
```
    Constant tag for long constants.
    
    See Also:
    Constant Field Values
  - DOUBLE
```
public static final byte DOUBLE
```
    Constant tag for double constants.
    
    See Also:
    Constant Field Values
  - INTERFACE_METHOD_REF
```
public static final byte INTERFACE_METHOD_REF
```
    Constant tag for method references. This is used to reference a method in an interface. The invokeinterface instruction uses this constant type.
    
    See Also:
    Constant Field Values
  - NAME_AND_TYPE
```
public static final byte NAME_AND_TYPE
```
    Constant tag for holding the name and type of a field or method. The Fieldref, Methodref and InterfaceMethodref constant types refer to this constant type.
    
    See Also:
    Constant Field Values
  - UTF8
```
public static final byte UTF8
```
    Constant tag for holding a UTF8 format string. The string is used to hold the name and type descriptor for NameandType constants, the class name for Class constants, the string value for String constants.
    
    See Also:
    Constant Field Values
  - METHOD_HANDLE
```
public static final byte METHOD_HANDLE
```
    Constant tag for holding a method handle.
    
    See Also:
    Constant Field Values
  - METHOD_TYPE
```
public static final byte METHOD_TYPE
```
    Constant tag for holding a method type.
    
    See Also:
    Constant Field Values
  - INVOKE_DYNAMIC
```
public static final byte INVOKE_DYNAMIC
```
    Constant tag for holding a bootstrap method.
    
    See Also:
    Constant Field Values
- Method Detail
  - tag
```
public final int tag()
```
    Get the tag of the constant.
    
    Returns:
    The tag.
  - value
```
public final java.lang.Object value()
```
    Get the value of the constant.
    
    Returns:
    The value.
  - hashCode
```
public int hashCode()
```
    Hash the constant.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    The hash code.
  - equals
```
public boolean equals(java.lang.Object other)
```
    Check if an object is equal to this constant.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    other - The object to compare against.
    
    Returns:
    true if equal, false if not.

Class Constant

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

tag

value

CLASS

FIELD_REF

METHOD_REF

STRING

INTEGER

FLOAT

LONG

DOUBLE

INTERFACE_METHOD_REF

NAME_AND_TYPE

UTF8

METHOD_HANDLE

METHOD_TYPE

INVOKE_DYNAMIC

Method Detail

tag

value

hashCode

equals