Parsers should target the previous LTS to support non-LTS versions (#6055)

* Parsers should target the previous LTS to support non-LTS versions

* Document why we're setting lower target compatibility

* `Java17ParserVisitor` requires 17 for `ClassTree.getPermitsClause`

* Catch `Throwable` in `JavaParser` for `UnsupportedClassVersionError`

Author: timtebeek

rewrite-java-17/build.gradle.kts

@@ -31,7 +31,6 @@ java {
 }
 
 tasks.withType<JavaCompile>().configureEach {
-    // allows --add-exports to in spite of the JDK's restrictions on this
     sourceCompatibility = JavaVersion.VERSION_17.toString()
     targetCompatibility = JavaVersion.VERSION_17.toString()
 

rewrite-java-21/build.gradle.kts

@@ -32,9 +32,9 @@ java {
 }
 
 tasks.withType<JavaCompile>().configureEach {
-    // allows --add-exports to in spite of the JDK's restrictions on this
-    sourceCompatibility = JavaVersion.VERSION_21.toString()
-    targetCompatibility = JavaVersion.VERSION_21.toString()
+    // Allow non-LTS versions before Java 21 to use this parser
+    sourceCompatibility = JavaVersion.VERSION_17.toString()
+    targetCompatibility = JavaVersion.VERSION_17.toString()
 
     options.release.set(null as Int?) // remove `--release 8` set in `org.openrewrite.java-base`
     options.compilerArgs.addAll(

rewrite-java-25/build.gradle.kts

@@ -34,9 +34,9 @@ java {
 tasks.named("licenseFormat") { enabled = false }
 
 tasks.withType<JavaCompile>().configureEach {
-    // allows --add-exports to in spite of the JDK's restrictions on this
-    sourceCompatibility = JavaVersion.VERSION_25.toString()
-    targetCompatibility = JavaVersion.VERSION_25.toString()
+    // Allow non-LTS versions before Java 25 to use this parser
+    sourceCompatibility = JavaVersion.VERSION_21.toString()
+    targetCompatibility = JavaVersion.VERSION_21.toString()
 
     options.release.set(null as Int?) // remove `--release 8` set in `org.openrewrite.java-base`
     options.compilerArgs.addAll(

rewrite-java-25/src/main/java/org/openrewrite/java/isolated/ReloadableJava25ParserVisitor.java

@@ -2232,17 +2232,17 @@ private int positionOfNext(String untilDelim, @Nullable Character stop) {
         return delimIndex > source.length() - untilDelim.length() ? -1 : delimIndex;
     }
 
-    private final Function<Tree, Space> semiDelim = _ -> {
+    private final Function<Tree, Space> semiDelim = t -> {
         Space prefix = whitespace();
         skip(";");
         return prefix;
     };
-    private final Function<Tree, Space> commaDelim = _ -> {
+    private final Function<Tree, Space> commaDelim = t -> {
         Space prefix = whitespace();
         skip(",");
         return prefix;
     };
-    private final Function<Tree, Space> noDelim = _ -> EMPTY;
+    private final Function<Tree, Space> noDelim = t -> EMPTY;
 
     private Space whitespace() {
         int nextNonWhitespace = indexOfNextNonWhitespace(cursor, source);

rewrite-java/src/main/java/org/openrewrite/java/JavaParser.java

@@ -168,7 +168,7 @@ static List<Path> dependenciesFromResources(ExecutionContext ctx, String... arti
                         .forName("org.openrewrite.java.Java25Parser")
                         .getDeclaredMethod("builder")
                         .invoke(null);
-            } catch (Exception e) {
+            } catch (Throwable e) {
                 //Fall through, look for a parser on an older version.
             }
         }
@@ -179,7 +179,7 @@ static List<Path> dependenciesFromResources(ExecutionContext ctx, String... arti
                         .forName("org.openrewrite.java.Java21Parser")
                         .getDeclaredMethod("builder")
                         .invoke(null);
-            } catch (Exception e) {
+            } catch (Throwable e) {
                 //Fall through, look for a parser on an older version.
             }
         }
@@ -190,7 +190,7 @@ static List<Path> dependenciesFromResources(ExecutionContext ctx, String... arti
                         .forName("org.openrewrite.java.Java17Parser")
                         .getDeclaredMethod("builder")
                         .invoke(null);
-            } catch (Exception e) {
+            } catch (Throwable e) {
                 //Fall through, look for a parser on an older version.
             }
         }
@@ -201,7 +201,7 @@ static List<Path> dependenciesFromResources(ExecutionContext ctx, String... arti
                         .forName("org.openrewrite.java.Java11Parser")
                         .getDeclaredMethod("builder")
                         .invoke(null);
-            } catch (Exception e) {
+            } catch (Throwable e) {
                 //Fall through, look for a parser on an older version.
             }
         }
@@ -211,7 +211,7 @@ static List<Path> dependenciesFromResources(ExecutionContext ctx, String... arti
                     .forName("org.openrewrite.java.Java8Parser")
                     .getDeclaredMethod("builder")
                     .invoke(null);
-        } catch (Exception e) {
+        } catch (Throwable e) {
             //Fall through to an exception without making this the "cause".
         }