com.base4j.mybatis.tool.ClassScanner Maven / Gradle / Ivy
package com.base4j.mybatis.tool;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarInputStream;
/**
* Created by USER on 2017-03-15.
*/
public class ClassScanner {
private Logger logger = LoggerFactory.getLogger(ClassScanner.class);
private String basePackage;
private ClassLoader cl;
/**
* Construct an instance and specify the base package it should scan.
* @param basePackage The base package to scan.
*/
public ClassScanner(String basePackage) {
this.basePackage = basePackage;
this.cl = getClass().getClassLoader();
}
/**
* Construct an instance with base package and class loader.
* @param basePackage The base package to scan.
* @param cl Use this class load to locate the package.
*/
public ClassScanner(String basePackage, ClassLoader cl) {
this.basePackage = basePackage;
this.cl = cl;
}
/**
* Get all fully qualified names located in the specified package
* and its sub-package.
*
* @return A list of fully qualified names.
* @throws IOException
*/
public List getFullyQualifiedClassNameList() throws IOException {
logger.info("开始扫描包{}下的所有类", basePackage);
return doScan(basePackage, new ArrayList());
}
/**
* Actually perform the scanning procedure.
*
* @param basePackage
* @param nameList A list to contain the result.
* @return A list of fully qualified names.
*
* @throws IOException
*/
private List doScan(String basePackage, List nameList) throws IOException {
// replace dots with splashes
String splashPath = StringUtil.dotToSplash(basePackage);
// get file path
URL url = cl.getResource(splashPath);
String filePath = StringUtil.getRootPath(url);
// Get classes in that package.
// If the web server unzips the jar file, then the classes will exist in the form of
// normal file in the directory.
// If the web server does not unzip the jar file, then classes will exist in jar file.
List names = null; // contains the name of the class file. e.g., Apple.class will be stored as "Apple"
if (isJarFile(filePath)) {
// jar file
if (logger.isDebugEnabled()) {
logger.debug("{} 是一个JAR包", filePath);
}
names = readFromJarFile(filePath, splashPath);
} else {
// directory
if (logger.isDebugEnabled()) {
logger.debug("{} 是一个目录", filePath);
}
names = readFromDirectory(filePath);
}
for (String name : names) {
if (isClassFile(name)) {
//nameList.add(basePackage + "." + StringUtil.trimExtension(name));
nameList.add(toFullyQualifiedName(name, basePackage));
} else {
// this is a directory
// check this directory for more classes
// do recursive invocation
doScan(basePackage + "." + name, nameList);
}
}
if (logger.isDebugEnabled()) {
for (String n : nameList) {
logger.debug("找到{}", n);
}
}
return nameList;
}
/**
* Convert short class name to fully qualified name.
* e.g., String -> java.lang.String
*/
private String toFullyQualifiedName(String shortName, String basePackage) {
// StringBuilder sb = new StringBuilder(basePackage);
// sb.append('.');
// sb.append(StringUtil.trimExtension(shortName));
return basePackage + "." + StringUtil.trimExtension(shortName);
}
private List readFromJarFile(String jarPath, String splashedPackageName) throws IOException {
if (logger.isDebugEnabled()) {
logger.debug("从JAR包中读取类: {}", jarPath);
}
jarPath = URLDecoder.decode(jarPath, "UTF-8");
JarInputStream jarIn = new JarInputStream(new FileInputStream(jarPath));
List nameList = new ArrayList();
JarEntry entry = jarIn.getNextJarEntry();
while (null != entry) {
String name = entry.getName();
if (name.startsWith(splashedPackageName) && isClassFile(name)) {
nameList.add(name);
}
entry = jarIn.getNextJarEntry();
}
return nameList;
}
private List readFromDirectory(String path) {
try {
path = URLDecoder.decode(path, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
File file = new File(path);
String[] names = file.list();
if (null == names) {
return null;
}
return Arrays.asList(names);
}
private boolean isClassFile(String name) {
return name.endsWith(".class");
}
private boolean isJarFile(String name) {
return name.endsWith(".jar");
}
/**
* For test purpose.
*/
public static void main(String[] args) throws Exception {
ClassScanner scan = new ClassScanner("com.base4j.base.orm.config");
List fullyQualifiedClassNameList = scan.getFullyQualifiedClassNameList();
System.out.println(fullyQualifiedClassNameList);
}
}