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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
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 * or LICENSE.txt.  See the License for the specific
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 * file and include the License file at LICENSE.txt.
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package javax.json;

import java.io.Serializable;
import java.util.AbstractList;
import java.util.Collections;
import java.util.List;
import java.util.RandomAccess;

/**
 * Private implementation of immutable {@link JsonArray}.
 *
 * @author Lukas Jungmann
 */
final class EmptyArray extends AbstractList<JsonValue> implements JsonArray, Serializable, RandomAccess {

    private static final long serialVersionUID = 7295439472061642859L;

    @Override
    public JsonValue get(int index) {
        throw new IndexOutOfBoundsException("Index: " + index);
    }

    @Override
    public int size() {
        return 0;
    }

    @Override
    public JsonObject getJsonObject(int index) {
        return (JsonObject) get(index);
    }

    @Override
    public JsonArray getJsonArray(int index) {
        return (JsonArray) get(index);
    }

    @Override
    public JsonNumber getJsonNumber(int index) {
        return (JsonNumber) get(index);
    }

    @Override
    public JsonString getJsonString(int index) {
        return (JsonString) get(index);
    }

    @Override
    public <T extends JsonValue> List<T> getValuesAs(Class<T> clazz) {
        return Collections.emptyList();
    }

    @Override
    public String getString(int index) {
        return getJsonString(index).getString();
    }

    @Override
    public String getString(int index, String defaultValue) {
        return defaultValue;
    }

    @Override
    public int getInt(int index) {
        return getJsonNumber(index).intValue();
    }

    @Override
    public int getInt(int index, int defaultValue) {
        return defaultValue;
    }

    @Override
    public boolean getBoolean(int index) {
        return get(index) == JsonValue.TRUE;
    }

    @Override
    public boolean getBoolean(int index, boolean defaultValue) {
        return defaultValue;
    }

    @Override
    public boolean isNull(int index) {
        return get(index) == JsonValue.NULL;
    }

    @Override
    public ValueType getValueType() {
        return ValueType.ARRAY;
    }

    // Preserves singleton property
    private Object readResolve() {
        return JsonValue.EMPTY_JSON_ARRAY;
    }
}