org.apache.lens.api.error.ErrorMap.java Source code

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Here is the source code for org.apache.lens.api.error.ErrorMap.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.lens.api.error;

import static org.apache.lens.api.error.LensCommonErrorCode.INTERNAL_SERVER_ERROR;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;

import java.util.LinkedList;
import java.util.List;

import com.google.common.base.Optional;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import lombok.NonNull;
import lombok.extern.slf4j.Slf4j;

/**
 * Map of errors created from error configuration file.
 */
@Slf4j
public class ErrorMap implements ErrorCollection {

    private final ImmutableMap<Integer, LensError> errors;

    public ErrorMap(@NonNull final ImmutableMap<Integer, LensError> errors) {

        checkArgument(!errors.isEmpty());
        this.errors = errors;

        /* All error pay load classes in error objects should be unique.
         * If two error objects are having same error code, then error pay load passed by them should also be same. */

        checkState(getErrorPayloadClassesList().size() == getErrorPayloadClasses().size(),
                "In error conf files, error objects defined with different error codes must have different"
                        + " error payload class.");
    }

    @Override
    public LensError getLensError(final int errorCode) {

        LensError lensError = errors.get(errorCode);

        if (lensError == null) {

            if (log.isWarnEnabled()) {
                log.warn(
                        "Error Code {} not found in initialized error collection. This could be a case of a pluggable code "
                                + "trying to send a random error code without initializing it in lens-errors.conf or "
                                + "lens-additional-errors.conf. We will drop this random error code and send INTERNAL SERVER ERROR "
                                + "instead of this.",
                        errorCode);
            }
            lensError = errors.get(INTERNAL_SERVER_ERROR.getValue());
        }
        return lensError;
    }

    @Override
    public ImmutableSet<Class> getErrorPayloadClasses() {

        return ImmutableSet.copyOf(getErrorPayloadClassesList());
    }

    private ImmutableList<Class> getErrorPayloadClassesList() {

        List<Class> errorPayloadClasses = new LinkedList<Class>();

        for (LensError lensError : errors.values()) {

            Optional<Class> errorPayloadClass = lensError.getPayloadClass();
            if (errorPayloadClass.isPresent()) {
                errorPayloadClasses.add(errorPayloadClass.get());
            }
        }
        return ImmutableList.copyOf(errorPayloadClasses);
    }
}