Allow to set severity per signature

This closes #252 and #219

Author: kwin

src/main/docs/ant-task.html

@@ -73,6 +73,20 @@ <h2>Parameters</h2>
   <td>Name of a <a href="bundled-signatures.html">built-in signatures</a> file.</td>
 </tr>
 
+<tr>
+  <td>signaturesWithSeveritySuppress</td>
+  <td><code>String</code></td>
+  <td></td>
+  <td>A forbidden API signature for which violations should not be reported at all (i.e. neither fail the build nor appear in the logs). This takes precedence over<code>failOnViolation</code> and <code>signaturesWithSeverityWarn</code>.</td>
+</tr>
+
+<tr>
+  <td>signaturesWithSeverityWarn</td>
+  <td><code>String</code></td>
+  <td></td>
+  <td>A forbidden API signature for which violations should be reported as warnings (i.e. not fail the build). This takes precedence over<code>failOnViolation</code>.</td>
+</tr>
+
 <tr>
   <td>classpath</td>
   <td><code>Path</code></td>
@@ -184,7 +198,7 @@ <h2>Parameters specified as nested elements</h2>
 
 <p>This task supports all <a href="https://ant.apache.org/manual/Types/resources.html">Ant resource</a> types
 (<code>fileset</code>, <code>filelist</code>, <code>file</code>, <code>tarfileset</code>, <code>zipfileset</code>,...)
-and uses all class files from them. It automatically adds an implcit filter to file names ending in <code>'.class'</code>,
+and uses all class files from them. It automatically adds an implicit filter to file names ending in <code>'.class'</code>,
 so you don't need to add this as include attribute to those collections.</p>
 
 <p>You can also pass one or multiple <code>classpath</code> elements to form a classpath. Ideally use the same configuration like the <code>javac</code> task.</p>

src/main/java/de/thetaphi/forbiddenapis/Checker.java

@@ -30,6 +30,7 @@
 import java.net.URL;
 import java.net.URLConnection;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.LinkedHashSet;
@@ -45,6 +46,8 @@
 import org.objectweb.asm.ClassReader;
 import org.objectweb.asm.Type;
 
+import de.thetaphi.forbiddenapis.Checker.ViolationSeverity;
+
 /**
  * Forbidden APIs checker class.
  */
@@ -58,6 +61,10 @@ public static enum Option {
     DISABLE_CLASSLOADING_CACHE
   }
 
+  public enum ViolationSeverity {
+      ERROR, WARNING, INFO, DEBUG, SUPPRESS
+  }
+
   public final boolean isSupportedJDK;
 
   private final long start;
@@ -360,6 +367,11 @@ public boolean noSignaturesFilesParsed() {
     return forbiddenSignatures.noSignaturesFilesParsed();
   }
 
+  /** Adjusts the severity of a specific signature. */
+  public void setSignaturesSeverity(Collection<String> signatures, ViolationSeverity severity) throws ParseException, IOException {
+    forbiddenSignatures.setSignaturesSeverity(signatures, severity);
+  }
+  
   /** Parses and adds a class from the given stream to the list of classes to check. Closes the stream when parsed (on Exception, too)! Does not log anything. */
   public void addClassToCheck(final InputStream in, String name) throws IOException {
     final ClassReader reader;
@@ -417,7 +429,7 @@ public void addSuppressAnnotation(String annoName) {
   /** Parses a class and checks for valid method invocations */
   private int checkClass(ClassMetadata c, Pattern suppressAnnotationsPattern) throws ForbiddenApiException {
     final String className = c.getBinaryClassName();
-    final ClassScanner scanner = new ClassScanner(c, this, forbiddenSignatures, suppressAnnotationsPattern); 
+    final ClassScanner scanner = new ClassScanner(c, this, forbiddenSignatures, suppressAnnotationsPattern, options.contains(Option.FAIL_ON_VIOLATION)); 
     try {
       c.getReader().accept(scanner, ClassReader.SKIP_FRAMES);
     } catch (RelatedClassLoadingException rcle) {
@@ -452,12 +464,31 @@ private int checkClass(ClassMetadata c, Pattern suppressAnnotationsPattern) thro
     }
     final List<ForbiddenViolation> violations = scanner.getSortedViolations();
     final Pattern splitter = Pattern.compile(Pattern.quote(ForbiddenViolation.SEPARATOR));
+    int numErrors = 0;
     for (final ForbiddenViolation v : violations) {
+      if (v.severity == ViolationSeverity.ERROR) {
+        numErrors++;
+      }
       for (final String line : splitter.split(v.format(className, scanner.getSourceFile()))) {
-        logger.error(line);
+        switch (v.severity) {
+        case DEBUG:
+          logger.debug(line);
+          break;
+        case INFO:
+          logger.info(line);
+          break;
+        case WARNING:
+          logger.warn(line);
+          break;
+        case ERROR:
+          logger.error(line);
+          break;
+        default:
+          break;
+        }
       }
     }
-    return violations.size();
+    return numErrors;
   }
 
   public void run() throws ForbiddenApiException {
@@ -483,5 +514,4 @@ public void run() throws ForbiddenApiException {
       logger.info(message);
     }
   }
-  
 }