Spring常用工具类

package com.baobaotao.io;
import java.io.IOException;
import java.io.InputStream;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.FileSystemResource;
import org.springframework.core.io.Resource;
public class FileSourceExample {
    public static void main(String[] args) {
        try {
            String filePath =
            "D:/masterSpring/chapter23/webapp/WEB-INF/classes/conf/file1.txt";
            // ① 使用系统文件路径方式加载文件
            Resource res1 = new FileSystemResource(filePath);
            // ② 使用类路径方式加载文件
            Resource res2 = new ClassPathResource("conf/file1.txt");
            InputStream ins1 = res1.getInputStream();
            InputStream ins2 = res2.getInputStream();
            System.out.println("res1:"+res1.getFilename());
            System.out.println("res2:"+res2.getFilename());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

File clsFile = ResourceUtils.getFile("classpath:conf/file1.txt");  
System.out.println(clsFile.isFile());
String httpFilePath = "file:D:/masterSpring/chapter23/src/conf/file1.txt";
File httpFile = ResourceUtils.getFile(httpFilePath);

package com.baobaotao.io;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileReader;
import java.io.OutputStream;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.util.FileCopyUtils;
public class FileCopyUtilsExample {
    public static void main(String[] args) throws Throwable {
        Resource res = new ClassPathResource("conf/file1.txt");
        // ① 将文件内容拷贝到一个 byte[] 中
        byte[] fileData = FileCopyUtils.copyToByteArray(res.getFile());
        // ② 将文件内容拷贝到一个 String 中
        String fileStr = FileCopyUtils.copyToString(new FileReader(res.getFile()));
        // ③ 将文件内容拷贝到另一个目标文件
        FileCopyUtils.copy(res.getFile(),
        new File(res.getFile().getParent()+ "/file2.txt"));
        // ④ 将文件内容拷贝到一个输出流中
        OutputStream os = new ByteArrayOutputStream();
        FileCopyUtils.copy(res.getInputStream(), os);
    }
}
static void copy(byte[] in, File out)     将 byte[] 拷贝到一个文件中
static void copy(byte[] in, OutputStream out)     将 byte[] 拷贝到一个输出流中
static int copy(File in, File out)     将文件拷贝到另一个文件中
static int copy(InputStream in, OutputStream out)     将输入流拷贝到输出流中
static int copy(Reader in, Writer out)     将 Reader 读取的内容拷贝到 Writer 指向目标输出中
static void copy(String in, Writer out)     将字符串拷贝到一个 Writer 指向的目标中属性文件操作  
Spring 提供的 PropertiesLoaderUtils 允许您直接通过基于类路径的文件 地址加载属性资源  
package com.baobaotao.io;
import java.util.Properties;
import org.springframework.core.io.support.PropertiesLoaderUtils;
public class PropertiesLoaderUtilsExample {
    public static void main(String[] args) throws Throwable {   
    // ① jdbc.properties 是位于类路径下的文件
  Properties props = PropertiesLoaderUtils.loadAllProperties("jdbc.properties");
  System.out.println(props.getProperty("jdbc.driverClassName"));
    }
}

package com.baobaotao.io;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.EncodedResource;
import org.springframework.util.FileCopyUtils;
public class EncodedResourceExample {
        public static void main(String[] args) throws Throwable  {
            Resource res = new ClassPathResource("conf/file1.txt");
            // ① 指定文件资源对应的编码格式（UTF-8）
            EncodedResource encRes = new EncodedResource(res,"UTF-8");
            // ② 这样才能正确读取文件的内容，而不会出现乱码
            String content  = FileCopyUtils.copyToString(encRes.getReader());
            System.out.println(content); 
    }
}

ServletContext servletContext = request.getSession().getServletContext();
WebApplicationContext wac = WebApplicationContextUtils. getWebApplicationContext(servletContext);

<filter>
    <filter-name>hibernateFilter</filter-name>
    <filter-class>
    org.springframework.orm.hibernate3.support.OpenSessionInViewFilter
    </filter-class>
</filter>
<filter-mapping>
    <filter-name>hibernateFilter</filter-name>
    <url-pattern>*.html</url-pattern>
</filter-mapping>

<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>
    org.springframework.web.filter.CharacterEncodingFilter ① Spring 编辑过滤器
</filter-class>
<init-param> ② 编码方式
    <param-name>encoding</param-name>
    <param-value>UTF-8</param-value>
</init-param>
<init-param> ③ 强制进行编码转换
    <param-name>forceEncoding</param-name>
    <param-value>true</param-value>
</init-param>
</filter>
<filter-mapping> ② 过滤器的匹配 URL
    <filter-name>encodingFilter</filter-name>
    <url-pattern>*.html</url-pattern>
</filter-mapping>

① 指定 Log4J 配置文件的地址
<context-param>
    <param-name>log4jConfigLocation</param-name>
    <param-value>/WEB-INF/log4j.properties</param-value>
</context-param>
② 使用该监听器初始化 Log4J 日志引擎
<listener>
    <listener-class>
    org.springframework.web.util.Log4jConfigListener
    </listener-class>
</listener>
Introspector 缓存清除监听器,防止内存泄露
<listener>
    <listener-class>
    org.springframework.web.util.IntrospectorCleanupListener
    </listener-class>
</listener>