public Builder setSource(ByteSource source) {
            this.source = source;
            return this;
        }
Sets the source data that will be hashed by a {@link HashService}. For example, this might be a
{@code ByteSource} representation of a password, or file, etc.

@param source the source data that will be hashed by a {@link HashService}.
@return this {@code Builder} instance for method chaining.
@see HashRequest#getSource()
@see #setSource(Object)
crypto/hash/src/main/java/org/apache/shiro/crypto/hash/HashRequest.java