# Class Query

java.lang.Object
javax.management.Query

public class Query extends Object

Constructs query object constraints.

The MBean Server can be queried for MBeans that meet a particular condition, using its `queryNames` or `queryMBeans` method. The `QueryExp` parameter to the method can be any implementation of the interface `QueryExp`, but it is usually best to obtain the `QueryExp` value by calling the static methods in this class. This is particularly true when querying a remote MBean Server: a custom implementation of the `QueryExp` interface might not be present in the remote MBean Server, but the methods in this class return only standard classes that are part of the JMX implementation.

As an example, suppose you wanted to find all MBeans where the `Enabled` attribute is `true` and the `Owner` attribute is `"Duke"`. Here is how you could construct the appropriate `QueryExp` by chaining together method calls:

    QueryExp query =
        Query.and(Query.eq(Query.attr("Enabled"), Query.value(true)),
                  Query.eq(Query.attr("Owner"), Query.value("Duke")));

Since:
  1.5

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `DIV`
  A code representing the `div(ValueExp, ValueExp)` expression.
  `static final int`
  `EQ`
  A code representing the `eq(ValueExp, ValueExp)` query.
  `static final int`
  `GE`
  A code representing the `geq(ValueExp, ValueExp)` query.
  `static final int`
  `GT`
  A code representing the `gt(ValueExp, ValueExp)` query.
  `static final int`
  `LE`
  A code representing the `leq(ValueExp, ValueExp)` query.
  `static final int`
  `LT`
  A code representing the `lt(ValueExp, ValueExp)` query.
  `static final int`
  `MINUS`
  A code representing the `minus(ValueExp, ValueExp)` expression.
  `static final int`
  `PLUS`
  A code representing the `plus(ValueExp, ValueExp)` expression.
  `static final int`
  `TIMES`
  A code representing the `times(ValueExp, ValueExp)` expression.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Query()`
  Basic constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static QueryExp`
  `and(QueryExp q1, QueryExp q2)`
  Returns a query expression that is the conjunction of two other query expressions.
  `static QueryExp`
  `anySubString(AttributeValueExp a, StringValueExp s)`
  Returns a query expression that represents a matching constraint on a string argument.
  `static AttributeValueExp`
  `attr(String name)`
  Returns a new attribute expression.
  `static AttributeValueExp`
  `attr(String className, String name)`
  Returns a new qualified attribute expression.
  `static QueryExp`
  `between(ValueExp v1, ValueExp v2, ValueExp v3)`
  Returns a query expression that represents the constraint that one value is between two other values.
  `static AttributeValueExp`
  `classattr()`
  Returns a new class attribute expression which can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `div(ValueExp value1, ValueExp value2)`
  Returns a binary expression representing the quotient of two numeric values.
  `static QueryExp`
  `eq(ValueExp v1, ValueExp v2)`
  Returns a query expression that represents an equality constraint on two values.
  `static QueryExp`
  `finalSubString(AttributeValueExp a, StringValueExp s)`
  Returns a query expression that represents a matching constraint on a string argument.
  `static QueryExp`
  `geq(ValueExp v1, ValueExp v2)`
  Returns a query expression that represents a "greater than or equal to" constraint on two values.
  `static QueryExp`
  `gt(ValueExp v1, ValueExp v2)`
  Returns a query expression that represents a "greater than" constraint on two values.
  `static QueryExp`
  `in(ValueExp val, ValueExp[] valueList)`
  Returns an expression constraining a value to be one of an explicit list.
  `static QueryExp`
  `initialSubString(AttributeValueExp a, StringValueExp s)`
  Returns a query expression that represents a matching constraint on a string argument.
  `static QueryExp`
  `isInstanceOf(StringValueExp classNameValue)`
  Returns a query expression that represents an inheritance constraint on an MBean class.
  `static QueryExp`
  `leq(ValueExp v1, ValueExp v2)`
  Returns a query expression that represents a "less than or equal to" constraint on two values.
  `static QueryExp`
  `lt(ValueExp v1, ValueExp v2)`
  Returns a query expression that represents a "less than" constraint on two values.
  `static QueryExp`
  `match(AttributeValueExp a, StringValueExp s)`
  Returns a query expression that represents a matching constraint on a string argument.
  `static ValueExp`
  `minus(ValueExp value1, ValueExp value2)`
  Returns a binary expression representing the difference between two numeric values.
  `static QueryExp`
  `not(QueryExp queryExp)`
  Returns a constraint that is the negation of its argument.
  `static QueryExp`
  `or(QueryExp q1, QueryExp q2)`
  Returns a query expression that is the disjunction of two other query expressions.
  `static ValueExp`
  `plus(ValueExp value1, ValueExp value2)`
  Returns a binary expression representing the sum of two numeric values, or the concatenation of two string values.
  `static ValueExp`
  `times(ValueExp value1, ValueExp value2)`
  Returns a binary expression representing the product of two numeric values.
  `static ValueExp`
  `value(boolean val)`
  Returns a boolean value expression that can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `value(double val)`
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `value(float val)`
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `value(int val)`
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `value(long val)`
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  `static ValueExp`
  `value(Number val)`
  Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
  `static StringValueExp`
  `value(String val)`
  Returns a new string expression.

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### GT

    public static final int GT
    A code representing the `gt(ValueExp, ValueExp)` query. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### LT

    public static final int LT
    A code representing the `lt(ValueExp, ValueExp)` query. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### GE

    public static final int GE
    A code representing the `geq(ValueExp, ValueExp)` query. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### LE

    public static final int LE
    A code representing the `leq(ValueExp, ValueExp)` query. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### EQ

    public static final int EQ
    A code representing the `eq(ValueExp, ValueExp)` query. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### PLUS

    public static final int PLUS
    A code representing the `plus(ValueExp, ValueExp)` expression. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### MINUS

    public static final int MINUS
    A code representing the `minus(ValueExp, ValueExp)` expression. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### TIMES

    public static final int TIMES
    A code representing the `times(ValueExp, ValueExp)` expression. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

  - ### DIV

    public static final int DIV
    A code representing the `div(ValueExp, ValueExp)` expression. This is chiefly of interest for the serialized form of queries.
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Query

    public Query()
    Basic constructor.

- ## Method Details

  - ### and

    public static QueryExp and(QueryExp q1, QueryExp q2)
    Returns a query expression that is the conjunction of two other query expressions.
    Parameters:
      `q1` - A query expression.
      `q2` - Another query expression.
    Returns:
      The conjunction of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.AndQueryExp.

  - ### or

    public static QueryExp or(QueryExp q1, QueryExp q2)
    Returns a query expression that is the disjunction of two other query expressions.
    Parameters:
      `q1` - A query expression.
      `q2` - Another query expression.
    Returns:
      The disjunction of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.OrQueryExp.

  - ### gt

    public static QueryExp gt(ValueExp v1, ValueExp v2)
    Returns a query expression that represents a "greater than" constraint on two values.
    Parameters:
      `v1` - A value expression.
      `v2` - Another value expression.
    Returns:
      A "greater than" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a `relOp` equal to `GT`.

  - ### geq

    public static QueryExp geq(ValueExp v1, ValueExp v2)
    Returns a query expression that represents a "greater than or equal to" constraint on two values.
    Parameters:
      `v1` - A value expression.
      `v2` - Another value expression.
    Returns:
      A "greater than or equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a `relOp` equal to `GE`.

  - ### leq

    public static QueryExp leq(ValueExp v1, ValueExp v2)
    Returns a query expression that represents a "less than or equal to" constraint on two values.
    Parameters:
      `v1` - A value expression.
      `v2` - Another value expression.
    Returns:
      A "less than or equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a `relOp` equal to `LE`.

  - ### lt

    public static QueryExp lt(ValueExp v1, ValueExp v2)
    Returns a query expression that represents a "less than" constraint on two values.
    Parameters:
      `v1` - A value expression.
      `v2` - Another value expression.
    Returns:
      A "less than" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a `relOp` equal to `LT`.

  - ### eq

    public static QueryExp eq(ValueExp v1, ValueExp v2)
    Returns a query expression that represents an equality constraint on two values.
    Parameters:
      `v1` - A value expression.
      `v2` - Another value expression.
    Returns:
      A "equal to" constraint on the arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryRelQueryExp with a `relOp` equal to `EQ`.

  - ### between

    public static QueryExp between(ValueExp v1, ValueExp v2, ValueExp v3)
    Returns a query expression that represents the constraint that one value is between two other values.
    Parameters:
      `v1` - A value expression that is "between" v2 and v3.
      `v2` - Value expression that represents a boundary of the constraint.
      `v3` - Value expression that represents a boundary of the constraint.
    Returns:
      The constraint that v1 lies between v2 and v3. The returned object will be serialized as an instance of the non-public class javax.management.BetweenQueryExp.

  - ### match

    public static QueryExp match(AttributeValueExp a, StringValueExp s)
    Returns a query expression that represents a matching constraint on a string argument. The matching syntax is consistent with file globbing: supports "`?`", "`*`", "`[`", each of which may be escaped with "`\`"; character classes may use "`!`" for negation and "`-`" for range. (`*` for any character sequence, `?` for a single arbitrary character, `[...]` for a character sequence). For example: `a*b?c` would match a string starting with the character `a`, followed by any number of characters, followed by a `b`, any single character, and a `c`.
    Parameters:
      `a` - An attribute expression
      `s` - A string value expression representing a matching constraint
    Returns:
      A query expression that represents the matching constraint on the string argument. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  - ### attr

    public static AttributeValueExp attr(String name)

    Returns a new attribute expression. See `AttributeValueExp` for a detailed description of the semantics of the expression.

    Evaluating this expression for a given `objectName` includes performing `MBeanServer.getAttribute(objectName, name)`.

    Parameters:
      `name` - The name of the attribute.
    Returns:
      An attribute expression for the attribute named `name`.

  - ### attr

    public static AttributeValueExp attr(String className, String name)

    Returns a new qualified attribute expression.

    Evaluating this expression for a given `objectName` includes performing `MBeanServer.getObjectInstance(objectName)` and `MBeanServer.getAttribute(objectName, name)`.

    Parameters:
      `className` - The name of the class possessing the attribute.
      `name` - The name of the attribute.
    Returns:
      An attribute expression for the attribute named name. The returned object will be serialized as an instance of the non-public class javax.management.QualifiedAttributeValueExp.

  - ### classattr

    public static AttributeValueExp classattr()

    Returns a new class attribute expression which can be used in any Query call that expects a ValueExp.

    Evaluating this expression for a given `objectName` includes performing `MBeanServer.getObjectInstance(objectName)`.

    Returns:
      A class attribute expression. The returned object will be serialized as an instance of the non-public class javax.management.ClassAttributeValueExp.

  - ### not

    public static QueryExp not(QueryExp queryExp)
    Returns a constraint that is the negation of its argument.
    Parameters:
      `queryExp` - The constraint to negate.
    Returns:
      A negated constraint. The returned object will be serialized as an instance of the non-public class javax.management.NotQueryExp.

  - ### in

    public static QueryExp in(ValueExp val, ValueExp[] valueList)
    Returns an expression constraining a value to be one of an explicit list.
    Parameters:
      `val` - A value to be constrained.
      `valueList` - An array of ValueExps.
    Returns:
      A QueryExp that represents the constraint. The returned object will be serialized as an instance of the non-public class javax.management.InQueryExp.

  - ### value

    public static StringValueExp value(String val)
    Returns a new string expression.
    Parameters:
      `val` - The string value.
    Returns:
      A ValueExp object containing the string argument.

  - ### value

    public static ValueExp value(Number val)
    Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - An instance of Number.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  - ### value

    public static ValueExp value(int val)
    Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - An int value.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  - ### value

    public static ValueExp value(long val)
    Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - A long value.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  - ### value

    public static ValueExp value(float val)
    Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - A float value.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  - ### value

    public static ValueExp value(double val)
    Returns a numeric value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - A double value.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.NumericValueExp.

  - ### value

    public static ValueExp value(boolean val)
    Returns a boolean value expression that can be used in any Query call that expects a ValueExp.
    Parameters:
      `val` - A boolean value.
    Returns:
      A ValueExp object containing the argument. The returned object will be serialized as an instance of the non-public class javax.management.BooleanValueExp.

  - ### plus

    public static ValueExp plus(ValueExp value1, ValueExp value2)
    Returns a binary expression representing the sum of two numeric values, or the concatenation of two string values.
    Parameters:
      `value1` - The first '+' operand.
      `value2` - The second '+' operand.
    Returns:
      A ValueExp representing the sum or concatenation of the two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an `op` equal to `PLUS`.

  - ### times

    public static ValueExp times(ValueExp value1, ValueExp value2)
    Returns a binary expression representing the product of two numeric values.
    Parameters:
      `value1` - The first '*' operand.
      `value2` - The second '*' operand.
    Returns:
      A ValueExp representing the product. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an `op` equal to `TIMES`.

  - ### minus

    public static ValueExp minus(ValueExp value1, ValueExp value2)
    Returns a binary expression representing the difference between two numeric values.
    Parameters:
      `value1` - The first '-' operand.
      `value2` - The second '-' operand.
    Returns:
      A ValueExp representing the difference between two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an `op` equal to `MINUS`.

  - ### div

    public static ValueExp div(ValueExp value1, ValueExp value2)
    Returns a binary expression representing the quotient of two numeric values.
    Parameters:
      `value1` - The first '/' operand.
      `value2` - The second '/' operand.
    Returns:
      A ValueExp representing the quotient of two arguments. The returned object will be serialized as an instance of the non-public class javax.management.BinaryOpValueExp with an `op` equal to `DIV`.

  - ### initialSubString

    public static QueryExp initialSubString(AttributeValueExp a, StringValueExp s)
    Returns a query expression that represents a matching constraint on a string argument. The value must start with the given literal string value.
    Parameters:
      `a` - An attribute expression.
      `s` - A string value expression representing the beginning of the string value.
    Returns:
      The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  - ### anySubString

    public static QueryExp anySubString(AttributeValueExp a, StringValueExp s)
    Returns a query expression that represents a matching constraint on a string argument. The value must contain the given literal string value.
    Parameters:
      `a` - An attribute expression.
      `s` - A string value expression representing the substring.
    Returns:
      The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  - ### finalSubString

    public static QueryExp finalSubString(AttributeValueExp a, StringValueExp s)
    Returns a query expression that represents a matching constraint on a string argument. The value must end with the given literal string value.
    Parameters:
      `a` - An attribute expression.
      `s` - A string value expression representing the end of the string value.
    Returns:
      The constraint that a matches s. The returned object will be serialized as an instance of the non-public class javax.management.MatchQueryExp.

  - ### isInstanceOf

    public static QueryExp isInstanceOf(StringValueExp classNameValue)
    Returns a query expression that represents an inheritance constraint on an MBean class.

    Example: to find MBeans that are instances of `NotificationBroadcaster`, use `Query.isInstanceOf(Query.value(NotificationBroadcaster.class.getName()))`.

    Evaluating this expression for a given `objectName` includes performing `MBeanServer.isInstanceOf(objectName, ((StringValueExp)classNameValue.apply(objectName)).getValue()`.

    Parameters:
      `classNameValue` - The `StringValueExp` returning the name of the class of which selected MBeans should be instances.
    Returns:
      a query expression that represents an inheritance constraint on an MBean class. The returned object will be serialized as an instance of the non-public class javax.management.InstanceOfQueryExp.
    Since:
      1.6