49 lines
1.2 KiB
Java
49 lines
1.2 KiB
Java
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// exceptions/EffectivelyFinalTWR.java
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// (c)2021 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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// {NewFeature} Since JDK 9
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import java.io.*;
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public class EffectivelyFinalTWR {
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static void old() {
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try (
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InputStream r1 = new FileInputStream(
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new File("TryWithResources.java"));
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InputStream r2 = new FileInputStream(
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new File("EffectivelyFinalTWR.java"));
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) {
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r1.read();
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r2.read();
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} catch(IOException e) {
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// Handle exceptions
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}
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}
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static void jdk9() throws IOException {
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final InputStream r1 = new FileInputStream(
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new File("TryWithResources.java"));
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// Effectively final:
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InputStream r2 = new FileInputStream(
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new File("EffectivelyFinalTWR.java"));
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try (r1; r2) {
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r1.read();
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r2.read();
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}
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// r1 and r2 are still in scope. Accessing
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// either one throws an exception:
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r1.read();
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r2.read();
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}
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public static void main(String[] args) {
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old();
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try {
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jdk9();
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} catch(IOException e) {
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System.out.println(e);
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}
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}
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}
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/* Output:
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java.io.IOException: Stream Closed
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*/
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