Grouping variables as classes

[-]

If I have a class that has, among others, several fields such as

public class SomeClass {

private long startTime...
private long endTime...

// some other fields here

...

public SomeClass() {
}

public long getStartTime() {
return startTime;
}

...
}

is it a good idea if I do this:


public class SomeClass {

private TimeInfo timeInfo = new TimeInfo();

// some other fields here

...

public SomeClass() {
}

public TimeInfo getTimeInfo() {
return timeInfo;
}

protected static class TimeInfo {

private long startTime ...
private long endTime ...

...

public TimeInfo() {
}

public long getStart() {
return start;
}

...
}
}

This way, I can use 'getStart()' and 'getEnd()' rather than
'getStartTime()' and 'getEndTime()'.

Anything I should know of?

 

[Raymond DeCampo]

If I have a class that has, among others, several fields such as

public class SomeClass {

private long startTime...
private long endTime...

// some other fields here

...

public SomeClass() {
}

public long getStartTime() {
return startTime;
}

...
}

is it a good idea if I do this:


public class SomeClass {

private TimeInfo timeInfo = new TimeInfo();

// some other fields here

...

public SomeClass() {
}

public TimeInfo getTimeInfo() {
return timeInfo;
}

protected static class TimeInfo {

private long startTime ...
private long endTime ...

...

public TimeInfo() {
}

public long getStart() {
return start;
}

...
}
}

This way, I can use 'getStart()' and 'getEnd()' rather than
'getStartTime()' and 'getEndTime()'.

Anything I should know of?

Why don't you just use the shorter names in the original class?
Unless TimeInfo is re-used somehow this appears to be a pointless change.

Ray

 

[Wibble]

If I have a class that has, among others, several fields such as

public class SomeClass {

private long startTime...
private long endTime...

// some other fields here

...

public SomeClass() {
}

public long getStartTime() {
return startTime;
}

...
}

is it a good idea if I do this:


public class SomeClass {

private TimeInfo timeInfo = new TimeInfo();

// some other fields here

...

public SomeClass() {
}

public TimeInfo getTimeInfo() {
return timeInfo;
}

protected static class TimeInfo {

private long startTime ...
private long endTime ...

...

public TimeInfo() {
}

public long getStart() {
return start;
}

...
}
}

This way, I can use 'getStart()' and 'getEnd()' rather than
'getStartTime()' and 'getEndTime()'.

Anything I should know of?

Its a fine pattern, particularly if the nested class has meaning, like a
time range. Consider initializing timeinfo like:

private TimeInfo timeInfo = newTimeInfo();
protected TimeInfo newTimeInfo() { return(new TimeInfo()); }

so that subclasses can override.

 

[Wibble]

Why don't you just use the shorter names in the original class?
Unless TimeInfo is re-used somehow this appears to be a pointless change.

Ray

Yeah, I dont understand the name change either, especially since the
long names are more clear. Its generally a bad idea to have more than
one name for anything. Saving typing is a bad excuse.

If the containing class is the only consumer, particularly if the
semantics are local, then it can make sense to nest. It can make code
more clear and makes it easy to promote the class to standalone later.