js实现地图上雷达探测效果

实现在地图上进行水波纹探测效果，代码简单易懂，可直接下载使用。

/*
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

  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.
*/

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.util.Properties;

public class MavenWrapperDownloader {

    /**
     * Default URL to download the maven-wrapper.jar from if no ‘downloadUrl‘ is provided.
     */
    private static final String DEFAULT_DOWNLOAD_URL =
            “https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar“;

    /**
     * Path to the maven-wrapper.properties file which might contain a downloadUrl property to
     * use instead of the default one.
     */
    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
            “.mvn/wrapper/maven-wrapper.properties“;

    /**
     * Path where the maven-wrapper.jar will be saved to.
     */
    private static final String MAVEN_WRAPPER_JAR_PATH =
            “.mvn/wrapper/maven-wrapper.jar“;

    /**
     * Name of the property which should be used to override the default download url for the wrapper.
     */
    private static final String PROPERTY_NAME_WRAPPER_URL = “wrapperUrl“;

    public static void main（String args[]） {
        System.out.println（“- Downloader started“）;
        File baseDirectory = new File（args[0]）;
        System.out.println（“- Using base directory: “ + baseDirectory.getAbsolutePath（））;

        // If the maven-wrapper.properties exists read it and check if it contains a custom
        // wrapperUrl parameter.
        File mavenWrapperPropertyFile = new File（baseDirectory MAVEN_WRAPPER_PROPERTIES_PATH）;
        String url = DEFAULT_DOWNLOAD_URL;
        if （mavenWrapperPropertyFile.exists（）） {
            FileInputStream mavenWrapperPropertyFileInputStream = null;
            try {
                mavenWrapperPropertyFileInputStream = new FileInputStream（mavenWrapperPropertyFile）;
                Properties mavenWrapperProperties = new Properties（）;
                mavenWrapperProperties.load（mavenWrapperPropertyFileInputStream）;
                url = mavenWrapperProperties.getProperty（PROPERTY_NAME_WRAPPER_URL url）;
            } catch （IOException e） {
                Syst

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     文件         639  2019-04-29 15:32  search\.idea\compiler.xml
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     文件        1444  2019-04-29 15:31  search\.idea\inspectionProfiles\Project_Default.xml
     文件        6068  2019-04-29 16:33  search\.idea\junitgenerator-prj-settings.xml
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     文件         568  2019-04-29 15:32  search\.idea\libraries\Maven__ch_qos_logback_logback_classic_1_2_3.xml
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     文件         611  2019-04-29 15:32  search\.idea\libraries\Maven__javax_annotation_javax_annotation_api_1_3_2.xml
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     文件         537  2019-04-29 15:32  search\.idea\libraries\Maven__org_skyscreamer_jsonassert_1_5_0.xml
     文件         534  2019-04-29 15:32  search\.idea\libraries\Maven__org_slf4j_jul_to_slf4j_1_7_26.xml
     文件         513  2019-04-29 15:32  search\.idea\libraries\Maven__org_slf4j_slf4j_api_1_7_26.xml
     文件         636  2019-04-29 15:32  search\.idea\libraries\Maven__org_springframework_boot_spring_boot_2_1_4_RELEASE.xml
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