/*
 * CREDIT SUISSE IS WILLING TO LICENSE THIS SPECIFICATION TO YOU ONLY UPON THE
 * CONDITION THAT YOU ACCEPT ALL OF THE TERMS CONTAINED IN THIS AGREEMENT.
 * PLEASE READ THE TERMS AND CONDITIONS OF THIS AGREEMENT CAREFULLY. BY
 * DOWNLOADING THIS SPECIFICATION, YOU ACCEPT THE TERMS AND CONDITIONS OF THE
 * AGREEMENT. IF YOU ARE NOT WILLING TO BE BOUND BY IT, SELECT THE "DECLINE"
 * BUTTON AT THE BOTTOM OF THIS PAGE. Specification: JSR-354 Money and Currency
 * API ("Specification") Copyright (c) 2012-2013, Credit Suisse All rights
 * reserved.
 */
package javax.money;

import java.util.Collections;
import java.util.List;

Represents a general context of data targeting an item of type Q. Contexts are used to add arbitrary data that cannot be be mapped in a standard way to the money API, e.g. use case or customer specific extensions os specialities.

Superclasses of this class must be final, immutable, serializable and thread-safe.
/**
 * Represents a general context of data targeting an item of type {@code Q}. Contexts are used to add arbitrary
 * data that cannot be be mapped in a standard way to the money API, e.g. use case or customer specific
 * extensions os specialities.<p>
 * Superclasses of this class must be final, immutable, serializable and thread-safe.
 */
public abstract class AbstractQuery extends AbstractContext {

	private static final long serialVersionUID = 5309190820845869327L;

	
Key for storing the target providers to be queried
/**
     * Key for storing the target providers to be queried
     */
    protected static final String KEY_QUERY_PROVIDERS = "Query.providers";

    
Key name for the timestamp attribute.
/**
     * Key name for the timestamp attribute.
     */
    protected static final String KEY_QUERY_TIMESTAMP = "Query.timestamp";

    
Key name for the target type attribute.
/**
     * Key name for the target type attribute.
     */
    protected static final String KEY_QUERY_TARGET_TYPE = "Query.targetType";


    
Constructor, using a builder.
Params:
builder – the builder, not null./**
     * Constructor, using a builder.
     *
     * @param builder the builder, not null.
     */
    protected AbstractQuery(@SuppressWarnings("rawtypes") AbstractQueryBuilder builder) {
        super(builder);
    }

    
Returns the providers and their ordering to be considered. This information typically must be interpreted by the singleton SPI implementations, which are backing the singleton accessors. If the list returned is empty, the default provider list, determined by methods like getDefaultProviderNames() should be used. 
Returns:
the ordered providers, never null./**
     * Returns the providers and their ordering to be considered. This information typically must be interpreted by the
     * singleton SPI implementations, which are backing the singleton accessors.
     * If the list returned is empty, the default provider list,
     * determined by methods like {@code getDefaultProviderNames()} should be used.
     *
     * @return the ordered providers, never null.
     */
    public List<String> getProviderNames() {

        @SuppressWarnings("unchecked") List<String> result = get(KEY_QUERY_PROVIDERS, List.class);
        if (result == null) {
            return Collections.emptyList();
        }
        return result;
    }

    
Gets the target implementation type required. This can be used to explicitly acquire a specific implementation
type and use a query to configure the instance or factory to be returned.
Returns:
this Builder for chaining./**
     * Gets the target implementation type required. This can be used to explicitly acquire a specific implementation
     * type and use a query to configure the instance or factory to be returned.
     *
     * @return this Builder for chaining.
     */
    public Class<?> getTargetType() {
        return get(KEY_QUERY_TARGET_TYPE, Class.class);
    }

}