nosum-spring/src/main/java/cn/nosum/framework/beans/support/BeanDefinitionReader.java

package cn.nosum.framework.beans.support;

import cn.nosum.framework.beans.BeanDefinition;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

public class BeanDefinitionReader {
    private List<String> registryBeanClasses=new ArrayList<String>();
    private Properties config=new Properties();

    public BeanDefinitionReader(String... locations){
        InputStream is=this.getClass().getClassLoader().getResourceAsStream(locations[0].replace("classpath:",""));
        try {
            config.load(is);
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (null!=is){
                try { is.close(); } catch (IOException e) { e.printStackTrace(); }
            }
        }
        doScanner(config.getProperty("scanPackage"));
    }

    /**
     * 扫描
     */
    private void doScanner(String scanPackage){
        URL url=this.getClass().getClassLoader().getResource("/"+scanPackage.replaceAll("\\.","/"));
        if (url == null){ return; }
        File classPath=new File(url.getFile());
        File[] files = classPath.listFiles();
        if (files == null){return;}
        for (File file : files) {
            if (file.isDirectory()){
                doScanner(scanPackage+"."+file.getName());
            }else{
                if (file.getName().endsWith(".class")){
                    String className=scanPackage+"."+file.getName().replace(".class","");
                    registryBeanClasses.add(className);
                }
            }
        }
    }

    /**
     * 将扫描到的所有配置信息转换为 BeanDefinition 对象，以便于 IOC 操作
     */
    public List<BeanDefinition> loadBeanDefinitions(){
        List<BeanDefinition> result=new ArrayList<BeanDefinition>();
        try {
            for (String className : registryBeanClasses) {
                Class<?> beanClass=Class.forName(className);
                // 如果是一个接口，则使用实现类
                if (beanClass.isInterface()){continue;}
                result.add(doCreateBeanDefinition(toLowerFirstCase(beanClass.getSimpleName()),beanClass.getName()));
                // 如果实现了多个接口，那么当前的实例就是这些接口的实现，直接注入即可
                Class<?>[] interfaces=beanClass.getInterfaces();
                for (Class<?> i : interfaces) {
                    // 这里的 name 是接口的包.类
                    result.add(doCreateBeanDefinition(i.getName(),beanClass.getName()));
                }
            }
        }catch (Exception e){e.printStackTrace();}
        return result;
    }

    public BeanDefinition doCreateBeanDefinition(String factoryBeanName,String beanClassName){
        BeanDefinition beanDefinition=new BeanDefinition();
        beanDefinition.setBeanClassName(beanClassName);
        beanDefinition.setFactoryBeanName(factoryBeanName);
        return beanDefinition;
    }

    public  String toLowerFirstCase(String simpleName){
        char[] chars=simpleName.toCharArray();
        chars[0]+=32;
        return String.valueOf(chars);
    }

    public List<String> getRegistryBeanClasses() {
        return registryBeanClasses;
    }

    public void setRegistryBeanClasses(List<String> registryBeanClasses) {
        this.registryBeanClasses = registryBeanClasses;
    }

    public Properties getConfig() {
        return config;
    }

    public void setConfig(Properties config) {
        this.config = config;
    }
}