MyBatis-Generator逆向生成器

目录结构

内容：

1 导包

		<dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <scope>test</scope>
            <version>1.3.2</version>
            <optional>true</optional>
        </dependency>
		
		<dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.5</version>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.1</version>
        </dependency>

2 config.xml

xml 文件中的相关路径和参数根据自己的实际情况修改

# 一般自定义修改四个地方
1. <jdbcConnection>	
	自定义数据库地址
2. <javaModelGenerator
	自定义实体类存放路径
3. <javaClientGenerator
	自定义mapper的存放地址
4. <table tableName="****">
	要将哪些表生成为实体类

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd" >
<generatorConfiguration>

	<context id="entmobile" targetRuntime="MyBatis3">

		<plugin type="org.mybatis.generator.plugins.AddLimitOffsetPlugin" />
		<plugin type="org.mybatis.generator.plugins.ToStringPlugin" />

		<commentGenerator>
			<property name="suppressDate" value="true" />
			<!-- remove comments -->
			<property name="suppressAllComments" value="true" />
		</commentGenerator>

		<jdbcConnection driverClass="com.mysql.jdbc.Driver"
						connectionURL="jdbc:mysql://localhost:3306/****?useUnicode=true&amp;characterEncoding=UTF-8&amp;useSSL=false"
						userId="****" password="****" />

		<!-- java type resolver -->
		<javaTypeResolver>
			<property name="forceBigDecimals" value="false" />
		</javaTypeResolver>

		<!-- gem entity -->
		<!-- data -->
		<javaModelGenerator targetPackage="com.****.domain"
							targetProject="./src/main/java">
			<property name="enableSubPackages" value="true" />
			<property name="trimStrings" value="false" />
		</javaModelGenerator>

		<!--  -->
		<!-- gem annotated mapper -->
		<!-- data -->
		<javaClientGenerator type="ANNOTATEDMAPPER"
							 targetPackage="com.****.mapper"
							 targetProject="./src/main/java">
			<property name="enableSubPackages" value="true" />
		</javaClientGenerator>
		
		<!-- 表名-->
		<table tableName="****">
			<generatedKey column="id" sqlStatement="JDBC"/>
		</table>
		
	</context>
</generatorConfiguration>

3 AddLimitOffsetPlugin

public class AddLimitOffsetPlugin extends PluginAdapter {

	public boolean validate(List<String> warnings) {
		return true;
	}

	public boolean modelExampleClassGenerated(TopLevelClass topLevelClass,
			IntrospectedTable introspectedTable) {
		FullyQualifiedJavaType offsetType = new FullyQualifiedJavaType(
				"javax.annotation.Generated");
		topLevelClass.addImportedType(offsetType);
		topLevelClass.addAnnotation("@Generated(\"" + introspectedTable.getTableConfiguration().getTableName() + "\")");
		 PrimitiveTypeWrapper integerWrapper = FullyQualifiedJavaType.getIntInstance().getPrimitiveTypeWrapper();
		 
		Field limit = new Field();
		limit.setName("limit");
		limit.setVisibility(JavaVisibility.PRIVATE);
		limit.setType(integerWrapper);
		topLevelClass.addField(limit);

		Method limitSet = new Method();
		limitSet.setVisibility(JavaVisibility.PUBLIC);
		limitSet.setName("setLimit");
		limitSet.addParameter(new Parameter(integerWrapper, "limit"));
		limitSet.addBodyLine("this.limit = limit;");
		topLevelClass.addMethod(limitSet);

		Method limitGet = new Method();
		limitGet.setVisibility(JavaVisibility.PUBLIC);
		limitGet.setReturnType(integerWrapper);
		limitGet.setName("getLimit");
		limitGet.addBodyLine("return limit;");
		topLevelClass.addMethod(limitGet);

		Field offset = new Field();
		offset.setName("offset");
		offset.setVisibility(JavaVisibility.PRIVATE);
		offset.setType(integerWrapper);
		topLevelClass.addField(offset);

		Method offsetSet = new Method();
		offsetSet.setVisibility(JavaVisibility.PUBLIC);
		offsetSet.setName("setOffset");
		offsetSet.addParameter(new Parameter(integerWrapper, "offset"));
		offsetSet.addBodyLine("this.offset = offset;");
		topLevelClass.addMethod(offsetSet);

		Method offsetGet = new Method();
		offsetGet.setVisibility(JavaVisibility.PUBLIC);
		offsetGet.setReturnType(integerWrapper);
		offsetGet.setName("getOffset");
		offsetGet.addBodyLine("return offset;");
		topLevelClass.addMethod(offsetGet);

		return true;
	}

	public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(
			XmlElement element, IntrospectedTable introspectedTable) {
		XmlElement isNotNullElement = new XmlElement("if");
		isNotNullElement.addAttribute(new Attribute("test", "limit > 0"));
		isNotNullElement.addElement(new TextElement("limit ${limit}"));
		element.getElements().add(isNotNullElement);

		isNotNullElement = new XmlElement("if");
		isNotNullElement.addAttribute(new Attribute("test", "offset > 0"));
		isNotNullElement.addElement(new TextElement("offset ${offset}"));
		element.getElements().add(isNotNullElement);
		return true;
	}

}

4 Generator

/**
 * mybatis代码生成插件调用者.
 */
public class Generator {

    @Test
    public void generate() throws Exception {
        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;

        InputStream stream = Generator.class.getClassLoader().getResourceAsStream("generatorConfig.xml");

        ConfigurationParser cp = new ConfigurationParser(warnings);
        InputStreamReader reader = new InputStreamReader(stream, "utf-8");
        BufferedReader bufferedReader = new BufferedReader(reader);

        String line = bufferedReader.readLine();
        StringBuffer buffer = new StringBuffer();
        while (line != null) {
            buffer.append(line + "\n");
            line = bufferedReader.readLine();
        }
        String xmlWithParam = buffer.toString();
        
        System.out.println("------- xml config begin -------");
        System.out.println(xmlWithParam);
        System.out.println("------- xml config end -------");

        final Configuration config = cp.parseConfiguration(new ByteArrayInputStream(xmlWithParam.getBytes("utf-8")));
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
        System.out.println("------- generator begin -------");
        ProgressCallback cb = new ProgressCallback() {
            private Pattern SqlProviderPattern = Pattern.compile("\\w*SqlProvider\\.java");
            private List<String> taskNames = new ArrayList();

            @Override
            public void startTask(String taskName) {
                /*
                 * 输出这些信息从而知道 生成那些类了 
                * Generating Example class for table demo
                * Generating Primary Key class for table demo 
                * Generating Record class for table demo 
                * Generating Mapper Interface for table demo 
                * Generating SQL Provider for table demo 
                * Saving file DemoExample.java
                * Saving file DemoKey.java Saving file Demo.java
                * Saving file DemoMapper.java
                * Saving file DemoSqlProvider.java
                 */
                // System.out.println(taskName);
                taskNames.add( taskName);
            }

            @Override
            public void saveStarted(int arg0) {}

            @Override
            public void introspectionStarted(int arg0) {}

            @Override
            public void generationStarted(int arg0) {}

            @Override
            public void done() {
                for(String taskName : taskNames){
                Matcher matcher = SqlProviderPattern.matcher(taskName);
                    if (matcher.find()) {
                        final String SqlProviderFilename = matcher.group();
                        System.out.println("处理生成文件,selectByExample  增加mysql分页: " + SqlProviderFilename);
                        List<Context> contexts = config.getContexts();
                        FilenameFilter filter = new FilenameFilter() {
                            @Override
                            public boolean accept(File dir, String name) {
                                return SqlProviderFilename.equalsIgnoreCase(name);
                            }
                        };
                        boolean done = false;
                        for (Context ctx : contexts) {
                            if(done){
                                break;
                            }
                            String targetProject = ctx.getJavaClientGeneratorConfiguration().getTargetProject();
                            String targetPackage = ctx.getJavaClientGeneratorConfiguration().getTargetPackage();
                            String dir = targetProject.replaceAll("\\.", "\\\\") + "\\" + targetPackage.replaceAll("\\.", "\\\\");
                            System.out.println(System.getProperty("user.dir") + dir);
                            File mapperDir = new File(System.getProperty("user.dir"), dir);
                            File[] files = mapperDir.listFiles(filter);
                            if (files != null && files.length > 0) {
                                File sqlProviderFile = files[0];
                                try {
                                    Generator.addMysqlLimit(sqlProviderFile);
                                    done = true;
                                } catch (Exception e) {
                                    e.printStackTrace();
                                }
                            }
                        }
                        if(!done){
                             System.out.println("转换失败!!!! selectByExample  增加mysql分页: " + SqlProviderFilename);
                        } else {
                            System.out.println("转换成功!!!! selectByExample  增加mysql分页: " + SqlProviderFilename);
                        }
                    }
                }
            }

            @Override
            public void checkCancel() throws InterruptedException {}
        };
        myBatisGenerator.generate(cb);
        for (String warning : warnings) {
            System.out.println(warning);
        }
        System.out.println("------- generator end -------");
        // System.out.println(config.getClassPathEntries());
    }

    private static void addMysqlLimit(File sqlProviderFile) throws Exception {
        /*
         * 这是自动生成的selectByExample 中的代码片段
        if (example != null && example.getOrderByClause() != null) {
            ORDER_BY(example.getOrderByClause()); // 整个文件唯一
        }
        
        return SQL();
        
         * 将return SQL()改为下面片段即可:

        String sqlString = SQL();
        if (example != null && example.getLimit() != null) {
            sqlString += " limit " + example.getLimit();
        }
        if (example != null && example.getOffset() != null) {
            sqlString += " offset " + example.getOffset();
        }
        return sqlString;
         */
        BufferedReader reader = new BufferedReader( new FileReader(sqlProviderFile));
        List<String> lines = IOUtils.readLines(reader);
        reader.close();
        String limitString = "        String sqlString = SQL();\n" +
                "        if (example != null && example.getLimit() != null) {\n" +
                "            sqlString += \" limit \" + example.getLimit();\n" +
                "        }\n" +
                "        if (example != null && example.getOffset() != null) {\n" +
                "            sqlString += \" offset \" + example.getOffset();\n" +
                "        }\n" +
                "        return sqlString;";
        ArrayList<String> newLines = new ArrayList<String>();

        
        for (int i=0; i< lines.size();++i) {
            String line = lines.get(i);
            newLines.add(line );
            if(line.replaceAll(" ", "") .equalsIgnoreCase("ORDER_BY(example.getOrderByClause());")) {
                // 添加下一行大括号和空白行
                ++i;
                newLines.add(lines.get(i));
                ++i;
                newLines.add(lines.get(i));
                
                ++i; // 跳过 return SQL();
                newLines.addAll(Arrays.asList( limitString.split("\n")));
            }
        }
        
//        for (String line : newLines) {
//            System.out.println(line);
//        }
        FileOutputStream writer = new FileOutputStream(sqlProviderFile);
        IOUtils.writeLines(newLines, "\n",writer,"UTF-8");
        writer.close();
    }
    
    public static void main(String[] args) throws Exception {
       new Generator().generate();
    }
}