比properties更好用的读配置文件的方式

太过爱你忘了你带给我的痛 2023-10-06 22:28 154阅读 0赞

用properties.load()时总是要求改level为6，很不舒服  
学习了用别的方式读配置文件

案例如下：

### 一、需要的依赖有： ###

<dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>1.2.16</version>
            </dependency>
            
            <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>
                
                <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>

### 二、前提工作 ###

resources里建 config和generator包  
config里放配置文件，因为test和生产环境不一样，所以用这种方式  
test.properties

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

和config同级中放config.xml

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

### 三、configuration工具 ###

constant包中放configuration 代码如下

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);//获得文档对象
                Element root = doc.getRootElement();//获得根节点
                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);
        }
    }

### 四、测试 ###

写好了 最后测试一下

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);
        }
    }

这样比直接用properties确实好用多了