RestError.java

package org.resthub.common.model;

import org.springframework.util.ObjectUtils;

/**
 * Value object use to serialize REST error messages
 * @author Les Hazlewood
 */
public class RestError {

    /** HTTP status reason phrase, form example "Internal Server Error" **/
    private final String status;

    /** HTTP status code **/
    private final int code;

    /** Message for end users **/
    private final String message;

    /** Message for developers **/
    private final String developerMessage;

    /** Eventually an URL where we can get more information about the error **/
    private final String moreInfoUrl;

    /** The exception thrown **/
    private final Throwable throwable;

    public RestError(String status, int code, String message, String developerMessage, String moreInfoUrl, Throwable throwable) {
        if (status == null) {
            throw new NullPointerException("HttpStatus argument cannot be null.");
        }
        this.status = status;
        this.code = code;
        this.message = message;
        this.developerMessage = developerMessage;
        this.moreInfoUrl = moreInfoUrl;
        this.throwable = throwable;
    }

    public String getStatus() {
        return status;
    }

    public int getCode() {
        return code;
    }

    public String getMessage() {
        return message;
    }

    public String getDeveloperMessage() {
        return developerMessage;
    }

    public String getMoreInfoUrl() {
        return moreInfoUrl;
    }

    public Throwable getThrowable() {
        return throwable;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o instanceof RestError) {
            RestError re = (RestError) o;
            return ObjectUtils.nullSafeEquals(getStatus(), re.getStatus()) &&
                    getCode() == re.getCode() &&
                    ObjectUtils.nullSafeEquals(getMessage(), re.getMessage()) &&
                    ObjectUtils.nullSafeEquals(getDeveloperMessage(), re.getDeveloperMessage()) &&
                    ObjectUtils.nullSafeEquals(getMoreInfoUrl(), re.getMoreInfoUrl()) &&
                    ObjectUtils.nullSafeEquals(getThrowable(), re.getThrowable());
        }

        return false;
    }

    @Override
    public int hashCode() {
        //noinspection ThrowableResultOfMethodCallIgnored
        return ObjectUtils.nullSafeHashCode(new Object[]{
                getStatus(), getCode(), getMessage(), getDeveloperMessage(), getMoreInfoUrl(), getThrowable()
        });
    }

    public String toString() {
        //noinspection StringBufferReplaceableByString
        return new StringBuilder().append(getCode())
                .append(" (").append(getStatus()).append(" )")
                .toString();
    }

    public static class Builder {

        private String status;
        private int code;
        private String message;
        private String developerMessage;
        private String moreInfoUrl;
        private Throwable throwable;

        public Builder() {
        }

        public Builder setStatus(String status) {
            this.status = status;
            return this;
        }

        public Builder setCode(int code) {
            this.code = code;
            return this;
        }

        public Builder setMessage(String message) {
            this.message = message;
            return this;
        }

        public Builder setDeveloperMessage(String developerMessage) {
            this.developerMessage = developerMessage;
            return this;
        }

        public Builder setMoreInfoUrl(String moreInfoUrl) {
            this.moreInfoUrl = moreInfoUrl;
            return this;
        }

        public Builder setThrowable(Throwable throwable) {
            this.throwable = throwable;
            return this;
        }

        public RestError build() {
            if (this.status == null) {
                this.status = "Internal Server Error";
            }
            return new RestError(this.status, this.code, this.message, this.developerMessage, this.moreInfoUrl, this.throwable);
        }
    }
}