What is the best standard style for a toString implementation? [closed]

Answer 1

check out phps print_r($obj, true) or also serialize() could work, dont know exactly for what its needed for. jsons is also a clean solution, especially if u want to import the data in javascript environbments

Answer 2

Not a direct answer to the question, however below would be a time saver during initial development:

Disclaimer: Apache Commons library is used.

1. Add a new Eclipse template called xreflect in Java > Editor > Templates; Add below into its pattern textarea:

// ---------- template start ----------- //
${:import(org.apache.commons.lang.builder.EqualsBuilder,org.apache.commons.lang.builder.HashCodeBuilder,org.apache.commons.lang.builder.ReflectionToStringBuilder)}
/*
 * (non-Javadoc)
* @see java.lang.Object#equals(java.lang.Object)
 */
@Override
public boolean equals(
        final Object pObj) {
    return EqualsBuilder.reflectionEquals(this, pObj);
}

/*
 * (non-Javadoc)
 * @see java.lang.Object#toString()
 */
@Override
public String toString() {
    return ReflectionToStringBuilder.toString(this);
}

/*
 * (non-Javadoc)
 * @see java.lang.Object#hashCode()
 */
@Override
public int hashCode() {
    return HashCodeBuilder.reflectionHashCode(this);
}
// ---------- template end ----------- //

2. Give OK, OK
3. Just go to the end of a Java class, type xreflect and press Ctrl + Space to autofill equals(), toString() and hashCode() methods automatically.

Answer 3

I think the format produced by Guava's MoreObjects.toStringHelper() is pretty nice, but it's mainly just good to have some consistent format that you use:

public String toString() {
  return Objects.toStringHelper(this)
      .add("prop1", prop1)
      .add("prop2", prop2)
      .toString();
}

// Produces "SimpleClassName{prop1=foo, prop2=bar}"

Answer 4

Is there any standard, or simply just a best practice for a style?

No. The "best" output for a toString() method is determined by what you want to use it for. Is it for serializing the object state in a form that allows it to be deserialized? Is it for creating debug messages? Is it for rendering the object for display to end-users?

If you want to develop an in-house style for your debug/logging toString() methods, that's fine. But unless there was a requirement for this, I wouldn't bother. IMO, it is effort that could better be spent elsewhere.

Answer 5

If your objects have something that might be useful as an identifier, I'd implement something like your second example:

[SimpleClassName:id] { prop1:value, prop2:[NestedObject:id] { prop3:value }}

Where the id is whatever makes sense for that object to be an identifier - the name for the canonical Person object, a primary key for an object from a database, etc.

Answer 6

Since you asked about what other open source projects to, here's how jEdit does it, which is similar to Wouter's:

BufferChanging[what=BUFFER_CHANGING,source=org.gjt.sp.jedit.EditPane[active,global]]