org.springframework.boot.actuate.endpoint.EndpointId.java Source code

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Here is the source code for org.springframework.boot.actuate.endpoint.EndpointId.java

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/*
 * Copyright 2012-2019 the original author or authors.
 *
 * Licensed 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
 *
 *      https://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.springframework.boot.actuate.endpoint;

import java.util.HashSet;
import java.util.Locale;
import java.util.Set;
import java.util.regex.Pattern;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.util.Assert;

/**
 * An identifier for an actuator endpoint. Endpoint IDs may contain only letters, numbers
 * {@code '.'} and {@code '-'}. They must begin with a lower-case letter. Case and syntax
 * characters are ignored when comparing endpoint IDs.
 *
 * @author Phillip Webb
 * @since 2.0.6
 */
public final class EndpointId {

    private static final Log logger = LogFactory.getLog(EndpointId.class);

    private static final Set<String> loggedWarnings = new HashSet<>();

    private static final Pattern VALID_PATTERN = Pattern.compile("[a-zA-Z0-9\\.\\-]+");

    private static final Pattern WARNING_PATTERN = Pattern.compile("[\\.\\-]+");

    private final String value;

    private final String lowerCaseValue;

    private final String lowerCaseAlphaNumeric;

    private EndpointId(String value) {
        Assert.hasText(value, "Value must not be empty");
        Assert.isTrue(VALID_PATTERN.matcher(value).matches(), "Value must only contain valid chars");
        Assert.isTrue(!Character.isDigit(value.charAt(0)), "Value must not start with a number");
        Assert.isTrue(!Character.isUpperCase(value.charAt(0)), "Value must not start with an uppercase letter");
        if (WARNING_PATTERN.matcher(value).find()) {
            logWarning(value);
        }
        this.value = value;
        this.lowerCaseValue = value.toLowerCase(Locale.ENGLISH);
        this.lowerCaseAlphaNumeric = getAlphaNumerics(this.lowerCaseValue);
    }

    private String getAlphaNumerics(String value) {
        StringBuilder result = new StringBuilder(value.length());
        for (int i = 0; i < value.length(); i++) {
            char ch = value.charAt(i);
            if (ch >= 'a' && ch <= 'z' || ch >= '0' && ch <= '9') {
                result.append(ch);
            }
        }
        return result.toString();
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null || getClass() != obj.getClass()) {
            return false;
        }
        return this.lowerCaseAlphaNumeric.equals(((EndpointId) obj).lowerCaseAlphaNumeric);
    }

    @Override
    public int hashCode() {
        return this.lowerCaseAlphaNumeric.hashCode();
    }

    /**
     * Return a lower-case version of the endpoint ID.
     * @return the lower-case endpoint ID
     */
    public String toLowerCaseString() {
        return this.lowerCaseValue;
    }

    @Override
    public String toString() {
        return this.value;
    }

    /**
     * Factory method to create a new {@link EndpointId} of the specified value.
     * @param value the endpoint ID value
     * @return an {@link EndpointId} instance
     */
    public static EndpointId of(String value) {
        return new EndpointId(value);
    }

    /**
     * Factory method to create a new {@link EndpointId} from a property value. More
     * lenient than {@link #of(String)} to allow for common "relaxed" property variants.
     * @param value the property value to convert
     * @return an {@link EndpointId} instance
     */
    public static EndpointId fromPropertyValue(String value) {
        return new EndpointId(value.replace("-", ""));
    }

    static void resetLoggedWarnings() {
        loggedWarnings.clear();
    }

    private static void logWarning(String value) {
        if (logger.isWarnEnabled() && loggedWarnings.add(value)) {
            logger.warn(
                    "Endpoint ID '" + value + "' contains invalid characters, please migrate to a valid format.");
        }
    }

}