freemarker 生成 Java 代码

拼搏现实的明天。 2023-01-15 15:27 136阅读 0赞

一、导入maven依赖

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
      <modelVersion>4.0.0</modelVersion>
      <groupId>cn.test</groupId>
      <artifactId>freemarket</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <packaging>war</packaging>
     
      <dependencies>
               <dependency>
                 <groupId>org.freemarker</groupId>
                 <artifactId>freemarker</artifactId>
                 <version>2.3.23</version>
             </dependency>
            
     
        </dependencies>
        <build>
     
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>2.0.2</version>
                    <configuration>
                        <source>1.8</source>
                        <target>1.8</target>
                    </configuration>
                </plugin>
     
                
     
            </plugins>
            <finalName>${project.artifactId}</finalName>
        </build>
    </project>

二、新建com.freemarker.hello.templates包，并在该包下编写模板文件test.ftl

package ${classPath};
     
    //java项目www.fhadmin.org
    public class ${className} {
       private Integer ${Id};
       private String ${userName};
       private String ${password};
        
        public Integer get${Id}(){
            return ${Id};
        }
        
        public void set${Id}(Integer ${Id}){
            this.${Id}=${Id};
        }
        
        public String get${userName}(){
            return ${userName};
        }
     
        public void set${userName}(String ${userName}){
            this.${userName}=${userName};
        }
        
        public String get${password}(){
            return ${password};
        }
        
        public void set${password}(String ${password}){
            this.${password}=${password};
        }
    }

三、编写运行生成对应Java代码类

package com.freemark.hello;
     
    import java.io.BufferedWriter;
    import java.io.File;
    import java.io.FileOutputStream;
    import java.io.OutputStreamWriter;
    import java.io.Writer;
    import java.util.HashMap;
    import java.util.Map;
     
    import freemarker.template.Configuration;
    import freemarker.template.Template;
     
    //java项目www.fhadmin.org
    public class FreemarkerDemo {
        
        private static final String TEMPLATE_PATH = "src/main/java/com/freemark/hello/templates";
        private static final String CLASS_PATH = "src/main/java/com/freemark/hello";
        
        public static void main(String[] args) {
            // step1 创建freeMarker配置实例
            Configuration configuration = new Configuration();
            Writer out = null;
            try {
                // step2 获取模版路径
                configuration.setDirectoryForTemplateLoading(new File(TEMPLATE_PATH));
                // step3 创建数据模型
                Map<String, Object> dataMap = new HashMap<String, Object>();
                dataMap.put("classPath", "com.freemark.hello");
                dataMap.put("className", "User");
                dataMap.put("Id", "Id");
                dataMap.put("userName", "userName");
                dataMap.put("password","password");
                // step4 加载模版文件
                Template template = configuration.getTemplate("test.ftl");
                // step5 生成数据
                File docFile = new File(CLASS_PATH + "\\" + "User.java");
                out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(docFile)));
                // step6 输出文件
                template.process(dataMap, out);
                System.out.println("^^^^^^^^^^^^^^^^^^^^^^^^User.java 文件创建成功 !");
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (null != out) {
                        out.flush();
                    }
                } catch (Exception e2) {
                    e2.printStackTrace();
                }
            }
        }
     
    }

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四、步骤三成功，刷新(refresh)项目即可，看到com.freemark.hello有一个User类。

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