CmpOperator (AristaFlow Business Process Platform API)

java.lang.Object
- java.lang.Enum<CmpOperator>
- - de.aristaflow.adept2.model.orgmodel.CmpOperator

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<CmpOperator>
```
public enum CmpOperator
extends java.lang.Enum<CmpOperator>
```
The comparison operators used within the OrgModelManager to select certain entities based on their attribute values. For each operator one or more symbols are defined. These symbols (if they contain letters) are NOT case sensitive.
A common task in an implementation of the OrgModelManager involving an CmpOperator would be e.g. finding out the data type of an attribute (see ModelExplorer.getAttributeDataType(de.aristaflow.adept2.base.sessionmanagement.SessionToken, EntityType, String)), finding out the data type of an object (see DataType.getDataTypeForObject(Object)) and using canCompare(DataType, DataType) to determine whether a specific operator can be used to compare them.
Every comparison operator must be negatable. This results from the EXCEPT keyword (see Berr05, page 78).
If new DataTypes are added, canCompare(DataType, DataType) and negate() will most certainly have to be adapted, too.
If new CmpOperators are added, don't forget to update negate(), canCompare(DataType) and canCompare(DataType, DataType).

Author:

Patrick Schmidt

Enum Constant Summary

Enum Constants
Enum Constant and Description
`EQUAL` The "equal" operator.
`EQUAL_IGNORECASE` A case insensitive version of `EQUAL`.
`GREATER_THAN` the "greater than" operator; also allowed in the context of strings
`GREATER_THAN_OR_EQUAL` the "greater than or equal" operator; also allowed in the context of strings
`LESS_THAN` the "less than" operator; also allowed in the context of strings
`LESS_THAN_OR_EQUAL` the "less than or equal" operator; also allowed in the context of strings
`LIKE` The "like" operator works like SQL's LIKE operator.
`LIKE_IGNORECASE` A case insensitive version of `LIKE`.
`NOT_EQUAL` The "not equal" operator.
`NOT_EQUAL_IGNORECASE` A case insensitive version of `NOT_EQUAL`.
`NOT_LIKE` A negated `LIKE` operator.
`NOT_LIKE_IGNORECASE` A case insensitive version of `NOT_LIKE`.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`canCompare(DataType dataType)` Returns whether this comparison operator can generally work on the given data type.
`boolean`	`canCompare(DataType attributeDataType, DataType valueObjectDataType)` Returns whether this operator can compare the two given data types.
`static CmpOperator`	`getCmpOperatorFor(java.lang.String symbol)` Returns the `CmpOperator` for the given symbol or `null` if the symbol is not recognised.
`CmpOperator`	`negate()` Returns the negated version of this operator.
`java.lang.String`	`symbol()` Returns the first (most preferred) symbol for this operator.
`java.lang.String[]`	`symbols()` Returns an array containing all symbols defined for this operator.
`static CmpOperator`	`valueOf(java.lang.String name)` Returns the enum constant of this type with the specified name.
`static CmpOperator[]`	`values()` Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

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

- Enum Constant Detail
  - EQUAL
```
public static final CmpOperator EQUAL
```
    The "equal" operator. EQUAL and NOT_EQUAL are the only comparison operators that can work on null values.
  - NOT_EQUAL
```
public static final CmpOperator NOT_EQUAL
```
    The "not equal" operator. EQUAL and NOT_EQUAL are the only comparison operators that can work on null values.
  - EQUAL_IGNORECASE
```
public static final CmpOperator EQUAL_IGNORECASE
```
    A case insensitive version of EQUAL. This only works on strings, it does not work on null.
  - NOT_EQUAL_IGNORECASE
```
public static final CmpOperator NOT_EQUAL_IGNORECASE
```
    A case insensitive version of NOT_EQUAL. This only works on strings, it does not work on null.
  - GREATER_THAN
```
public static final CmpOperator GREATER_THAN
```
    the "greater than" operator; also allowed in the context of strings
  - GREATER_THAN_OR_EQUAL
```
public static final CmpOperator GREATER_THAN_OR_EQUAL
```
    the "greater than or equal" operator; also allowed in the context of strings
  - LESS_THAN
```
public static final CmpOperator LESS_THAN
```
    the "less than" operator; also allowed in the context of strings
  - LESS_THAN_OR_EQUAL
```
public static final CmpOperator LESS_THAN_OR_EQUAL
```
    the "less than or equal" operator; also allowed in the context of strings
  - LIKE
```
public static final CmpOperator LIKE
```
    The "like" operator works like SQL's LIKE operator. _ is a placeholder for exactly one character; % is a placeholder for an arbitrary number of characters (even zero). Only works on strings.
  - NOT_LIKE
```
public static final CmpOperator NOT_LIKE
```
    A negated LIKE operator. Only works on strings.
  - LIKE_IGNORECASE
```
public static final CmpOperator LIKE_IGNORECASE
```
    A case insensitive version of LIKE. When not using any placeholders this operator works like a case insensitive EQUAL. Only works on strings.
  - NOT_LIKE_IGNORECASE
```
public static final CmpOperator NOT_LIKE_IGNORECASE
```
    A case insensitive version of NOT_LIKE. When not using any placeholders this operator works like a case insensitive NOT_EQUAL. Only works on strings.
- Method Detail
  - values
```
public static CmpOperator[] values()
```
    Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
```
for (CmpOperator c : CmpOperator.values())
    System.out.println(c);
```
    Returns:
    
    an array containing the constants of this enum type, in the order they are declared
  - valueOf
```
public static CmpOperator valueOf(java.lang.String name)
```
    Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
    
    Parameters:
    
    name - the name of the enum constant to be returned.
    
    Returns:
    
    the enum constant with the specified name
    
    Throws:
    
    java.lang.IllegalArgumentException - if this enum type has no constant with the specified name
    
    java.lang.NullPointerException - if the argument is null
  - symbol
```
public java.lang.String symbol()
```
    Returns the first (most preferred) symbol for this operator.
    
    Returns:
    
    the first (most preferred) symbol for this operator
  - symbols
```
public java.lang.String[] symbols()
```
    Returns an array containing all symbols defined for this operator.
    
    Returns:
    
    an array containing all symbols defined for this operator
  - negate
```
public CmpOperator negate()
```
    Returns the negated version of this operator. E.g. calling this method on EQUAL will return NOT_EQUAL.
    This method must be updated if a new comparison operator is added!
    
    Returns:
    
    the negated version of this operator
  - canCompare
```
public boolean canCompare(DataType attributeDataType,
                          DataType valueObjectDataType)
```
    Returns whether this operator can compare the two given data types. The left-hand data type should be the attribute's data type and must never be DataType.NULL. The right-hand data type should be the data type of the value object or DataType.NULL if the value object itself is null. At the time of writing, only EQUAL and NOT_EQUAL can compare a null-value to the value of an attribute.
    
    Parameters:
    
    attributeDataType - the left-hand data type (which should be the attribute data type)
    
    valueObjectDataType - the right-hand data type (which should be the value object's data type or DataType.NULL)
    
    Returns:
    
    whether this operator can compare the two given data types
  - canCompare
```
public boolean canCompare(DataType dataType)
```
    Returns whether this comparison operator can generally work on the given data type. If it can, this at least guarantees that it can compare two values of this same type. If the parameter is DataType.NULL this method will determine if the operator can deal with null values (at the time of writing, only EQUAL and NOT_EQUAL can do that).
    
    Parameters:
    
    dataType - the data type to be tested
    
    Returns:
    
    whether this comparison operator can generally work on the given data type
  - getCmpOperatorFor
```
public static CmpOperator getCmpOperatorFor(java.lang.String symbol)
```
    Returns the CmpOperator for the given symbol or null if the symbol is not recognised.
    
    Parameters:
    
    symbol - the symbol for which the appropriate CmpOperator should be returned
    
    Returns:
    
    the CmpOperator for the given symbol or null if the symbol is not recognised

Enum CmpOperator

Enum Constant Summary

Method Summary

Methods inherited from class java.lang.Enum

Methods inherited from class java.lang.Object

Enum Constant Detail

EQUAL

NOT_EQUAL

EQUAL_IGNORECASE

NOT_EQUAL_IGNORECASE

GREATER_THAN

GREATER_THAN_OR_EQUAL

LESS_THAN

LESS_THAN_OR_EQUAL

LIKE

NOT_LIKE

LIKE_IGNORECASE

NOT_LIKE_IGNORECASE

Method Detail

values

valueOf

symbol

symbols

negate

canCompare

canCompare

getCmpOperatorFor