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/*
* Copyright © 2009 Reinier Zwitserloot and Roel Spilker.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package lombok;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Ensures the variable declaration that you annotate will be cleaned up by calling its close method, regardless
* of what happens. Implemented by wrapping all statements following the local variable declaration to the
* end of your scope into a try block that, as a finally action, closes the resource.
* <p>
* Example:
* <pre>
* public void copyFile(String in, String out) throws IOException {
* @Cleanup FileInputStream inStream = new FileInputStream(in);
* @Cleanup FileOutputStream outStream = new FileOutputStream(out);
* byte[] b = new byte[65536];
* while (true) {
* int r = inStream.read(b);
* if (r == -1) break;
* outStream.write(b, 0, r);
* }
* }
* </pre>
*
* Will generate:
* <pre>
* public void copyFile(String in, String out) throws IOException {
* @Cleanup FileInputStream inStream = new FileInputStream(in);
* try {
* @Cleanup FileOutputStream outStream = new FileOutputStream(out);
* try {
* byte[] b = new byte[65536];
* while (true) {
* int r = inStream.read(b);
* if (r == -1) break;
* outStream.write(b, 0, r);
* }
* } finally {
* out.close();
* }
* } finally {
* in.close();
* }
* }
* </pre>
*
* Note that the final close method call, if it throws an exception, will overwrite any exception thrown
* in the main body of the generated try block. You should NOT rely on this behaviour - future versions of
* lombok intend to silently swallow any exception thrown by the cleanup method <i>_IF</i> the main body
* throws an exception as well, as the earlier exception is usually far more useful.
* <p>
* However, in java 1.6, generating the code to do this is prohibitively complicated.
*/
@Target(ElementType.LOCAL_VARIABLE)
@Retention(RetentionPolicy.SOURCE)
public @interface Cleanup {
/** The name of the method that cleans up the resource. By default, 'close'. The method must not have any parameters. */
String value() default "close";
}
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