[FLINK-17530] Fix illegal reflective access by ClosureCleaner

• Type: Sub-task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.11.0
• Component/s: API / DataStream
• Assignee: Unassigned
• Reporter: Robert Metzger
• Created: 05/May/20 15:15
• Updated: 13/Apr/21 07:11

Description

To reproduce:

	@Test
	public void testJava11Warning() {
		MapFunction<String, String> fun = new MapFunction<String, String>() {
			String field = "asdf";
			@Override
			public String map(String value) throws Exception {
				return value + field;
			}
		};
		ClosureCleaner.clean(fun, ExecutionConfig.ClosureCleanerLevel.RECURSIVE, false);
	}

Causes:

WARNING: Illegal reflective access by org.apache.flink.api.java.ClosureCleaner (file:/Users/robert/Projects/flink/flink-core/target/classes/) to field java.lang.String.value
	at org.apache.flink.api.java.ClosureCleaner.clean(ClosureCleaner.java:104)
	at org.apache.flink.api.java.ClosureCleaner.clean(ClosureCleaner.java:126)
	at org.apache.flink.api.java.ClosureCleaner.clean(ClosureCleaner.java:71)
	at org.apache.flink.api.java.ClosureCleanerTest.testJava11Warning(ClosureCleanerTest.java:58)