标签:抽象 googl ngx src bug 注入 read 定义 com
1 有用部分
2 代码演练
个人理解:
1.1 关于lambda的应用
通过 @FunctionalInterface注解 将其参数 fileContent 注入,调用的时候可以直接调取到。
服务层通过直接调用接口的方法,没有用实现类
1.2 关于文件流的读取操作
demo中设计更多的流的读取的操作
需求:
将本地文件打印出来
接口:
package com.imooc.zhangxiaoxi.lambda.file; /** * 接口中只有一个抽象方法,可以应用lambda表达式 * * 加入注解 * * 文件处理函数式接口 */ @FunctionalInterface public interface FileConsumer { /** * 函数式接口抽象方法 * @param fileContent */ void fileHandler(String fileContent); }
文件服务类:
package com.imooc.zhangxiaoxi.lambda.file; import java.io.*; /** * 文件服务类 */ public class FileService { /** * 根据url获取文件,打印文件内容 */ public void print(String url,FileConsumer fileConsumer) throws IOException { //流读取 BufferedReader bufferedReader = new BufferedReader( new InputStreamReader( new FileInputStream(url))); //定义行变量和内容sb String line = ""; StringBuilder stringBuilder = new StringBuilder(); //循环读取文件内容 while((line=bufferedReader.readLine())!=null){ stringBuilder.append(line+"\n"); } //调用函数式接口方法,将文件内容传递给lambda表达式 fileConsumer.fileHandler(stringBuilder.toString()); } }
文件测试类:
package com.imooc.zhangxiaoxi.lambda.file; import org.junit.Test; import java.io.IOException; public class FileServiceTest { @Test public void Test() throws IOException {
//两种方式
//1.2 FileService fileService = new FileService(); fileService.print("F:/xiangmu3/Xin/test996/src/test/java/com/imooc/zhangxiaoxi/" + "lambda/file/FileServiceTest.java", fileContent -> { System.out.println(fileContent); }); //1.1 /*FileService fileService = new FileService(); fileService.print("F:/xiangmu3/Xin/test996/src/test/java/com/imooc/zhangxiaoxi/" + "lambda/file/FileServiceTest.java", fileContent -> System.out.println(fileContent));*/ } }
打印日志:
D:\java\jdk\jdk9\jdk-9+181_windows-x64_ri\java-se-9-ri\jdk-9\bin\java.exe -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:D:\java\devolopKit\idea\anZh\IntelliJ IDEA Community Edition 2018.1.4\lib\idea_rt.jar=30991:D:\java\devolopKit\idea\anZh\IntelliJ IDEA Community Edition 2018.1.4\bin" -Dfile.encoding=UTF-8 -classpath "D:\java\devolopKit\idea\anZh\IntelliJ IDEA Community Edition 2018.1.4\lib\idea_rt.jar;D:\java\devolopKit\idea\anZh\IntelliJ IDEA Community Edition 2018.1.4\plugins\junit\lib\junit-rt.jar;D:\java\devolopKit\idea\anZh\IntelliJ IDEA Community Edition 2018.1.4\plugins\junit\lib\junit5-rt.jar;F:\xiangmu3\Xin\test996\target\test-classes;F:\xiangmu3\Xin\test996\target\classes;F:\xiangmu3\Xin\test996\lib\com\google\guava\guava\28.2-jre\guava-28.2-jre.jar;F:\xiangmu3\Xin\test996\lib\com\google\guava\failureaccess\1.0.1\failureaccess-1.0.1.jar;F:\xiangmu3\Xin\test996\lib\com\google\guava\listenablefuture\9999.0-empty-to-avoid-conflict-with-guava\listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar;F:\xiangmu3\Xin\test996\lib\com\google\code\findbugs\jsr305\3.0.2\jsr305-3.0.2.jar;F:\xiangmu3\Xin\test996\lib\org\checkerframework\checker-qual\2.10.0\checker-qual-2.10.0.jar;F:\xiangmu3\Xin\test996\lib\com\google\errorprone\error_prone_annotations\2.3.4\error_prone_annotations-2.3.4.jar;F:\xiangmu3\Xin\test996\lib\com\google\j2objc\j2objc-annotations\1.3\j2objc-annotations-1.3.jar;F:\xiangmu3\Xin\test996\lib\junit\junit\4.12\junit-4.12.jar;F:\xiangmu3\Xin\test996\lib\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;F:\xiangmu3\Xin\test996\lib\com\alibaba\fastjson\1.2.58\fastjson-1.2.58.jar" com.intellij.rt.execution.junit.JUnitStarter -ideVersion5 -junit4 com.imooc.zhangxiaoxi.lambda.file.FileServiceTest,Test package com.imooc.zhangxiaoxi.lambda.file; import org.junit.Test; import java.io.IOException; public class FileServiceTest { @Test public void Test() throws IOException { //1.2 FileService fileService = new FileService(); fileService.print("F:/xiangmu3/Xin/test996/src/test/java/com/imooc/zhangxiaoxi/" + "lambda/file/FileServiceTest.java", fileContent -> { System.out.println(fileContent); }); //1.1 /*FileService fileService = new FileService(); fileService.print("F:/xiangmu3/Xin/test996/src/test/java/com/imooc/zhangxiaoxi/" + "lambda/file/FileServiceTest.java", fileContent -> System.out.println(fileContent));*/ } } Process finished with exit code 0
高效 告别996,开启java高效编程之门 2-10实战:自定义函数式接口
标签:抽象 googl ngx src bug 注入 read 定义 com
原文地址:https://www.cnblogs.com/1446358788-qq/p/12630756.html