public static T castPrimitive()

in brooklyn-server/core/src/main/java/org/apache/brooklyn/util/core/flags/TypeCoercions.java [348:424]
63 lines of code
29 McCabe index (conditional complexity)

    public static <T> T castPrimitive(Object value, Class<T> targetType) {
        if (value==null) return null;
        assert isPrimitiveOrBoxer(targetType) : "targetType="+targetType;
        assert isPrimitiveOrBoxer(value.getClass()) : "value="+targetType+"; valueType="+value.getClass();

        Class<?> sourceWrapType = Primitives.wrap(value.getClass());
        Class<?> targetWrapType = Primitives.wrap(targetType);
        
        // optimization, for when already correct type
        if (sourceWrapType == targetWrapType) {
            return (T) value;
        }
        
        if (targetWrapType == Boolean.class) {
            // only char can be mapped to boolean
            // (we could say 0=false, nonzero=true, but there is no compelling use case so better
            // to encourage users to write as boolean)
            if (sourceWrapType == Character.class)
                return (T) stringToPrimitive(value.toString(), targetType);
            
            throw new ClassCoercionException("Cannot cast "+sourceWrapType+" ("+value+") to "+targetType);
        } else if (sourceWrapType == Boolean.class) {
            // boolean can't cast to anything else
            
            throw new ClassCoercionException("Cannot cast "+sourceWrapType+" ("+value+") to "+targetType);
        }
        
        // for whole-numbers (where casting to long won't lose anything)...
        long v = 0;
        boolean islong = true;
        if (sourceWrapType == Character.class) {
            v = (long) ((Character)value).charValue();
        } else if (sourceWrapType == Byte.class) {
            v = (long) ((Byte)value).byteValue();
        } else if (sourceWrapType == Short.class) {
            v = (long) ((Short)value).shortValue();
        } else if (sourceWrapType == Integer.class) {
            v = (long) ((Integer)value).intValue();
        } else if (sourceWrapType == Long.class) {
            v = ((Long)value).longValue();
        } else {
            islong = false;
        }
        if (islong) {
            if (targetWrapType == Character.class) return (T) Character.valueOf((char)v); 
            if (targetWrapType == Byte.class) return (T) Byte.valueOf((byte)v); 
            if (targetWrapType == Short.class) return (T) Short.valueOf((short)v); 
            if (targetWrapType == Integer.class) return (T) Integer.valueOf((int)v); 
            if (targetWrapType == Long.class) return (T) Long.valueOf((long)v); 
            if (targetWrapType == Float.class) return (T) Float.valueOf((float)v); 
            if (targetWrapType == Double.class) return (T) Double.valueOf((double)v);
            throw new IllegalStateException("Unexpected: sourceType="+sourceWrapType+"; targetType="+targetWrapType);
        }
        
        // for real-numbers (cast to double)...
        double d = 0;
        boolean isdouble = true;
        if (sourceWrapType == Float.class) {
            d = (double) ((Float)value).floatValue();
        } else if (sourceWrapType == Double.class) {
            d = (double) ((Double)value).doubleValue();
        } else {
            isdouble = false;
        }
        if (isdouble) {
            if (targetWrapType == Character.class) return (T) Character.valueOf((char)d); 
            if (targetWrapType == Byte.class) return (T) Byte.valueOf((byte)d); 
            if (targetWrapType == Short.class) return (T) Short.valueOf((short)d); 
            if (targetWrapType == Integer.class) return (T) Integer.valueOf((int)d); 
            if (targetWrapType == Long.class) return (T) Long.valueOf((long)d); 
            if (targetWrapType == Float.class) return (T) Float.valueOf((float)d); 
            if (targetWrapType == Double.class) return (T) Double.valueOf((double)d);
            throw new IllegalStateException("Unexpected: sourceType="+sourceWrapType+"; targetType="+targetWrapType);
        } else {
            throw new IllegalStateException("Unexpected: sourceType="+sourceWrapType+"; targetType="+targetWrapType);
        }
    }