SensitivityWatchEventModifier.java

/*
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package com.sun.nio.file;

import java.nio.file.WatchEvent.Modifier;
import sun.nio.fs.ExtendedOptions;

/**
 * Defines the <em>sensitivity levels</em> when registering objects with a watch service implementation that polls the file system.
 *
 * @since 1.7
 */
/*
 * 目录监视的灵敏度可选参数
 *
 * 目前仅用在PollingWatchService实现中，灵敏度越高，搜集目录变动信息的行为越频繁。
 */
public enum SensitivityWatchEventModifier implements Modifier {
    
    /**
     * High sensitivity.
     */
    HIGH(ExtendedOptions.SENSITIVITY_HIGH, 2),
    
    /**
     * Medium sensitivity.
     */
    MEDIUM(ExtendedOptions.SENSITIVITY_MEDIUM, 10),
    
    /**
     * Low sensitivity.
     */
    LOW(ExtendedOptions.SENSITIVITY_LOW, 30);
    
    // 服务运行的时间间隔
    private final int sensitivity;
    
    SensitivityWatchEventModifier(ExtendedOptions.InternalOption<Integer> option, int sensitivity) {
        this.sensitivity = sensitivity;
        option.register(this, sensitivity);
    }
    
    /**
     * Returns the sensitivity in seconds.
     */
    public int sensitivityValueInSeconds() {
        return sensitivity;
    }
}