Added example code for Execute Around idiom.
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execute-around/src/main/java/com/iluwatar/App.java
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30
execute-around/src/main/java/com/iluwatar/App.java
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package com.iluwatar;
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import java.io.FileWriter;
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import java.io.IOException;
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/**
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* The Execute Around idiom specifies some code to be executed before and after
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* a method. Typically the idiom is used when the API has methods to be executed in
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* pairs, such as resource allocation/deallocation or lock acquisition/release.
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*
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* In this example, we have SimpleFileWriter class that opens and closes the file
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* for the user. The user specifies only what to do with the file by providing the
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* FileWriterAction implementation.
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*
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*/
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public class App {
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public static void main( String[] args ) throws IOException {
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new SimpleFileWriter("testfile.txt", new FileWriterAction() {
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@Override
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public void writeFile(FileWriter writer) throws IOException {
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writer.write("Hello");
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writer.append(" ");
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writer.append("there!");
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}
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});
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}
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}
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package com.iluwatar;
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import java.io.FileWriter;
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import java.io.IOException;
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/**
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*
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* Interface for specifying what to do with the file resource.
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*
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*/
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public interface FileWriterAction {
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void writeFile(FileWriter writer) throws IOException;
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}
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package com.iluwatar;
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import java.io.FileWriter;
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import java.io.IOException;
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/**
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*
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* SimpleFileWriter handles opening and closing file for the user. The user
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* only has to specify what to do with the file resource through FileWriterAction
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* parameter.
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*
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*/
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public class SimpleFileWriter {
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public SimpleFileWriter(String filename, FileWriterAction action) throws IOException {
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FileWriter writer = new FileWriter(filename);
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try {
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action.writeFile(writer);
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} finally {
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writer.close();
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}
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}
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}
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19
execute-around/src/test/java/com/iluwatar/AppTest.java
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19
execute-around/src/test/java/com/iluwatar/AppTest.java
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package com.iluwatar;
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import java.io.IOException;
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import org.junit.Test;
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/**
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*
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* Tests execute-around example.
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*
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*/
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public class AppTest {
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@Test
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public void test() throws IOException {
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String[] args = {};
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App.main(args);
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}
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}
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