Add option 'validateLeader' (#567)

Author: dr0i

metafacture-biblio/src/main/java/org/metafacture/biblio/marc21/Marc21Encoder.java

@@ -81,6 +81,7 @@ public final class Marc21Encoder extends
     private State state = State.IN_STREAM;
 
     private boolean generateIdField;
+    private boolean validateLeader = true;
 
     /**
      * Initializes the encoder with MARC 21 constants and charset.
@@ -108,6 +109,18 @@ public void setGenerateIdField(final boolean generateIdField) {
         this.generateIdField = generateIdField;
     }
 
+    /**
+     * Controls whether the leader should be validated.
+     * <p>
+     * The default value of {@code validateLeader} is true.
+     * <p>
+     *
+     * @param validateLeader if false the leader is not validated
+     */
+    public void setValidateLeader(final boolean validateLeader) {
+        this.validateLeader = validateLeader;
+    }
+
     /**
      * Gets the flag to decide whether the ID field is generated.
      *
@@ -259,12 +272,14 @@ private void processLeaderAsSubfields(final String name, final char code) {
     }
 
     private void requireValidCode(final char code, final char[] validCodes) {
-        for (final char validCode: validCodes) {
-            if (validCode == code) {
-                return;
+        if (validateLeader) {
+            for (final char validCode : validCodes) {
+                if (validCode == code) {
+                    return;
+                }
             }
+            throw new FormatException("invalid code '" + code + "'; allowed codes are: " + Arrays.toString(validCodes));
         }
-        throw new FormatException("invalid code '" + code + "'; allowed codes are: " + Arrays.toString(validCodes));
     }
 
     private void processTopLevelLiteral(final String name, final String value) {

metafacture-biblio/src/test/java/org/metafacture/biblio/marc21/Marc21EncoderTest.java

@@ -38,6 +38,8 @@
  */
 public final class Marc21EncoderTest {
 
+    private static final String BAD_LEADER = "00600ny  a22002053n 4500";
+
     private Marc21Encoder marc21Encoder;
 
     @Mock
@@ -147,4 +149,21 @@ public void issue524ShouldComputeValidLeader() {
         verify(receiver).process(matches("00055pam a2200037 c 4500021001700000\u001e.*\u001d"));
     }
 
+    @Test(expected = FormatException.class)
+    public void issue567ShouldFailValidateLeaderAsDefault() {
+        marc21Encoder.startRecord("");
+        marc21Encoder.literal(LEADER_ENTITY, BAD_LEADER);
+        marc21Encoder.endRecord();
+    }
+
+    @Test
+    public void issue567ShouldNotValidateLeader() {
+        marc21Encoder.setValidateLeader(false);
+        marc21Encoder.startRecord("");
+        marc21Encoder.literal(LEADER_ENTITY,   BAD_LEADER );
+        marc21Encoder.endRecord();
+
+        verify(receiver).process(matches("00026ny  a22000253n 4500\u001e\u001d"));
+    }
+
 }