Add ASN1Integer valueOf methods and small constants

Author: peterdettman

core/src/main/java/org/bouncycastle/asn1/ASN1Integer.java

@@ -20,6 +20,15 @@ ASN1Primitive fromImplicitPrimitive(DEROctetString octetString)
         }
     };
 
+    private static final ASN1Integer[] SMALL_CONSTANTS = new ASN1Integer[17];
+
+    public static final ASN1Integer ZERO;
+    public static final ASN1Integer ONE;
+    public static final ASN1Integer TWO;
+    public static final ASN1Integer THREE;
+    public static final ASN1Integer FOUR;
+    public static final ASN1Integer FIVE;
+
     static final int SIGN_EXT_SIGNED = 0xFFFFFFFF;
     static final int SIGN_EXT_UNSIGNED = 0xFF;
 
@@ -76,6 +85,48 @@ public static ASN1Integer getTagged(ASN1TaggedObject taggedObject, boolean decla
         return (ASN1Integer)TYPE.getTagged(taggedObject, declaredExplicit);
     }
 
+    public static ASN1Integer valueOf(int value)
+    {
+        if (value >= 0L && value < SMALL_CONSTANTS.length)
+            return SMALL_CONSTANTS[value];
+
+        return new ASN1Integer(value);
+    }
+
+    public static ASN1Integer valueOf(long value)
+    {
+        if (value >= 0L && value < SMALL_CONSTANTS.length)
+            return SMALL_CONSTANTS[(int)value];
+
+        return new ASN1Integer(value);
+    }
+
+    static
+    {
+        for (int i = 0; i < SMALL_CONSTANTS.length; ++i)
+        {
+            SMALL_CONSTANTS[i] = new ASN1Integer(i);
+        }
+
+        ZERO = SMALL_CONSTANTS[0];
+        ONE = SMALL_CONSTANTS[1];
+        TWO = SMALL_CONSTANTS[2];
+        THREE = SMALL_CONSTANTS[3];
+        FOUR = SMALL_CONSTANTS[4];
+        FIVE = SMALL_CONSTANTS[5];
+    }
+
+    /**
+     * Construct an INTEGER from the passed in int value.
+     *
+     * @param value the int representing the value desired.
+     */
+    public ASN1Integer(int value)
+    {
+        this.bytes = BigInteger.valueOf(value).toByteArray();
+        this.start = 0;
+    }
+
     /**
      * Construct an INTEGER from the passed in long value.
      *

core/src/main/java/org/bouncycastle/asn1/cryptopro/ECGOST3410ParamSetParameters.java

@@ -51,7 +51,7 @@ public ECGOST3410ParamSetParameters(
         this.b = new ASN1Integer(b);
         this.p = new ASN1Integer(p);
         this.q = new ASN1Integer(q);
-        this.x = new ASN1Integer(x);
+        this.x = ASN1Integer.valueOf(x);
         this.y = new ASN1Integer(y);
     }
 

core/src/main/java/org/bouncycastle/asn1/cryptopro/GOST3410ParamSetParameters.java

@@ -95,7 +95,7 @@ public ASN1Primitive toASN1Primitive()
     {
         ASN1EncodableVector v = new ASN1EncodableVector(4);
 
-        v.add(new ASN1Integer(keySize));
+        v.add(ASN1Integer.valueOf(keySize));
         v.add(p);
         v.add(q);
         v.add(a);

core/src/main/java/org/bouncycastle/asn1/nist/KMACwithSHAKE128_params.java

@@ -101,7 +101,7 @@ public ASN1Primitive toASN1Primitive()
 
         if (outputLength != DEF_LENGTH)
         {
-            v.add(new ASN1Integer(outputLength));
+            v.add(ASN1Integer.valueOf(outputLength));
         }
 
         if (customizationString.length != 0)

core/src/main/java/org/bouncycastle/asn1/nist/KMACwithSHAKE256_params.java

@@ -101,7 +101,7 @@ public ASN1Primitive toASN1Primitive()
 
         if (outputLength != DEF_LENGTH)
         {
-            v.add(new ASN1Integer(outputLength));
+            v.add(ASN1Integer.valueOf(outputLength));
         }
 
         if (customizationString.length != 0)

core/src/main/java/org/bouncycastle/asn1/ocsp/ResponseData.java

@@ -26,8 +26,8 @@
 public class ResponseData
     extends ASN1Object
 {
-    private static final ASN1Integer V1 = new ASN1Integer(0);
-    
+    private static final ASN1Integer V1 = ASN1Integer.ZERO;
+
     private boolean             versionPresent;
 
     private ASN1Integer          version;

core/src/main/java/org/bouncycastle/asn1/ocsp/TBSRequest.java

@@ -15,7 +15,7 @@
 public class TBSRequest
     extends ASN1Object
 {
-    private static final ASN1Integer V1 = new ASN1Integer(0);
+    private static final ASN1Integer V1 = ASN1Integer.ZERO;
 
     ASN1Integer      version;
     GeneralName     requestorName;

core/src/main/java/org/bouncycastle/asn1/pkcs/CertificationRequestInfo.java

@@ -36,7 +36,7 @@
 public class CertificationRequestInfo
     extends ASN1Object
 {
-    ASN1Integer              version = new ASN1Integer(0);
+    ASN1Integer             version = ASN1Integer.ZERO;
     X500Name                subject;
     SubjectPublicKeyInfo    subjectPKInfo;
     ASN1Set                 attributes = null;

core/src/main/java/org/bouncycastle/asn1/pkcs/DHParameter.java

@@ -25,7 +25,7 @@ public DHParameter(
 
         if (l != 0)
         {
-            this.l = new ASN1Integer(l);
+            this.l = ASN1Integer.valueOf(l);
         }
         else
         {

core/src/main/java/org/bouncycastle/asn1/pkcs/EncryptedData.java

@@ -102,6 +102,6 @@ public ASN1OctetString getContent()
 
     public ASN1Primitive toASN1Primitive()
     {
-        return new BERSequence(new ASN1Integer(0), data);
+        return new BERSequence(ASN1Integer.ZERO, data);
     }
 }