Better way to read configuration files than properties

use properties.load() Always ask to change level by 6, Very uncomfortable
Learned to read configuration files in other ways

The case is as follows ：

One 、 The dependencies needed are ：

 <!--log4j Log core package -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.16</version>
        </dependency>
        <!--xml Parse core package -->
        <dependency>
            <groupId>dom4j</groupId>
            <artifactId>dom4j</artifactId>
            <version>1.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.jdom</groupId>
            <artifactId>jdom2</artifactId>
            <version>2.0.5</version>
        </dependency>

<build>
        <sourceDirectory>src/main/java</sourceDirectory>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                    <include>**/*.log</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
        </resources>

        <plugins>
            <!-- mybatis generator  Auto generate code plug-in   Nothing to do with this case  -->
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.2</version>
                <configuration>
                    <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
                    <overwrite>true</overwrite>
                    <verbose>true</verbose>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>2.4.1</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <transformers>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                    <mainClass>com.Test</mainClass>
                                </transformer>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                                    <resource>META-INF/spring.handlers</resource>
                                </transformer>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                                    <resource>META-INF/spring.schemas</resource>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

Two 、 If work

resources Li Jian config and generator package
config Put the configuration file in , because test Different from the production environment , So in this way
test.properties

cloud.mysql.jdbc.driver=com.mysql.cj.jdbc.Driver

and config In the same level config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<configuration>
    <!-- Test environment -->
    <properties resource="config/test.properties"></properties>

</configuration>

3、 ... and 、configuration Tools

constant Bao Zhongfang configuration The code is as follows

package constant;

import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.input.SAXBuilder;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.Properties;

/** * @author zwh * @date 2022/4/20 */
public class Configuration extends Properties {
    
    public static final Logger log = LogManager.getLogger(Configuration.class);
    private static final long serialVersionUID = 50440463580273222L;

    private static Configuration instance = null;

    public Configuration() {
    
        InputStream in;
        try {
    
            in = this.getClass().getResourceAsStream("/"+ read());
            this.load(in);
            in.close();
        } catch (IOException e) {
    
            // TODO Auto-generated catch block
            log.error(e);
        }

    }

    public static synchronized Configuration getInstance() {
    
        if (instance == null) {
    
            instance = new Configuration();
        }
        return instance;
    }

    public String read() {
    
        String prefix = null;
        SAXBuilder builder = new SAXBuilder();
        InputStream file = this.getClass().getResourceAsStream("/config.xml");

        try {
    
            Document doc = builder.build(file);// Get document object 
            Element root = doc.getRootElement();// Get root node 
            List<Element> list = root.getChildren();
            for (Element e : list) {
    
                if (null != e.getAttribute("resource")) {
    
                    prefix = e.getAttribute("resource").getValue();
                }
            }
        } catch (Exception e) {
    
            log.error(e);
        }
        return prefix;
    }

    @Override
    public String getProperty(String key, String defaultValue) {
    
        String val = getProperty(key);
        return (val == null || val.isEmpty()) ? defaultValue : val;
    }

    public String getString(String name, String defaultValue) {
    
        return this.getProperty(name, defaultValue);
    }

    public int getInt(String name, int defaultValue) {
    
        String val = this.getProperty(name);
        return (val == null || val.isEmpty()) ? defaultValue : Integer.parseInt(val);
    }

    public long getLong(String name, long defaultValue) {
    
        String val = this.getProperty(name);
        return (val == null || val.isEmpty()) ? defaultValue : Integer.parseInt(val);
    }

    public float getFloat(String name, float defaultValue) {
    
        String val = this.getProperty(name);
        return (val == null || val.isEmpty()) ? defaultValue : Float.parseFloat(val);
    }

    public double getDouble(String name, double defaultValue) {
    
        String val = this.getProperty(name);
        return (val == null || val.isEmpty()) ? defaultValue : Double.parseDouble(val);
    }

    public byte getByte(String name, byte defaultValue) {
    
        String val = this.getProperty(name);
        return (val == null || val.isEmpty()) ? defaultValue : Byte.parseByte(val);
    }
}

Four 、 test

Well done. Finally, test it

package com;

import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;

/** * @author zwh * @date 2022/4/20 */
public class Test {
    
    public static final Logger log = LogManager.getLogger(Test.class);
    public static constant.Configuration config = constant.Configuration.getInstance();

    public static void main(String[] args) {
    

        String driverClassName = config.getString("cloud.mysql.jdbc.driver", "");

        System.out.println(driverClassName);
    }
}

This is better than using properties It's really much easier to use