Caching

Pm4j supports caching for several UI aspects. A cache may be configured by an annotation:

  @PmCacheCfg(value=CacheMode.ON)
  public final PmAttrInteger myAttr = new PmAttrIntgerImpl() {
    protected getValueImpl() {
        // … some expensive code. E.g. a service call … 

You may define caches for multiple UI aspects:

@PmCacheCfg(title=CacheMode.ON, options=CacheMode.ON)

Caching is supported for the following UI aspects:

• visibility,
• enablement,
• title,
• value and
• options

You may cache all these UI aspects as follows:

@PmCacheCfg(all=CacheMode.ON)

Cache life time control

A cached value will be calculated on the first request for the cached.
The cached value will be used until the cache gets cleared.

PmCacheApi.clearPmCache()

A cache may be cleared programmatically by using the method:

PmCacheApi.clearPmCache(myPm);

This call clears all cached values for the given PM and all of its child PMs.
Specific cache aspects may be cleared by using the varargs parameter of this method:

PmCacheApi.clearPmCache(myPm, CacheKind.ENABLEMENT, CacheKind.OPTIONS);

Standard operations that clear cached values

The following operations automatically clear cached values:

• A cached attribute value gets replaced by the new value if the setValue() or setValueAsString() method gets called.
• A call to PmBean.setPmBean() and PmBean.reloadPmBean() clears all caches within the related PM sub tree.