Compact equals and hashcode

Question

I have a bean with 4 attributes:

user
institutionId
groupId
postingDate

I use Eclipse to generate equals and hashcode but the resulting code is not pretty. Is there a compact way to do the same? Assuming I want equals & hashcode to use all the attributes or a subset of them.

@Override
public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((groupId == null) ? 0 : groupId.hashCode());
    result = prime * result + ((institutionId == null) ? 0 : institutionId.hashCode());
    result = prime * result + ((postingDate == null) ? 0 : postingDate.hashCode());
    result = prime * result + ((user == null) ? 0 : user.hashCode());
    return result;
}

@Override
public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;
    ManGroupKey other = (ManGroupKey) obj;
    if (groupId == null) {
        if (other.groupId != null)
            return false;
    } else if (!groupId.equals(other.groupId))
        return false;
    if (institutionId == null) {
        if (other.institutionId != null)
            return false;
    } else if (!institutionId.equals(other.institutionId))
        return false;
    if (postingDate == null) {
        if (other.postingDate != null)
            return false;
    } else if (!postingDate.equals(other.postingDate))
        return false;
    if (user == null) {
        if (other.user != null)
            return false;
    } else if (!user.equals(other.user))
        return false;
    return true;
}

Answer 1

In Java 7

public int hashCode() {
    return Objects.hash(groupId, institutionId, postingDate, user);
}

public boolean equals(Object obj) {
    if (this == obj)
        return true;
    if (obj == null)
        return false;
    if (getClass() != obj.getClass())
        return false;

    // cast to correct class
    Target o = (Target)obj;

    return Objects.equals(groupId, o.groupId) &&
           Objects.equals(institutionId, o.institutionId) &&
           Objects.equals(postingDate, o.postingDate) &&
           Objects.equals(user, o.user);
}

Answer 2

You could compact the code down, but the odds are far higher that you would introduce bugs than that you would do anything useful. All the parts of the equals and hash code method are there for a reason.

If it's bothering you most IDEs have a folding editor, just click the little yellow box (usually) and all the contents of the method get hidden away.