Indicate your preferences for the Building settings on the   Java > Compiler > Building  preference page.
| Option | Description | Default | 
|---|---|---|
| Maximum number of reported problems per compilation unit | Specifies how many problems should be reported for a compilation unit. | 100 | 
| Enable use of exclusion patterns in source folders | When disabled, no entry on a project classpath can be associated with an exclusion pattern. | On | 
| Enable use of multiple output locations for source folders | When disabled, no entry on a project classpath can be associated with a specific output location, preventing thus usage of multiple output locations. | On | 
| Abort build when build path errors occur | Allow to toggle the builder to abort if the classpath is invalid. | On | 
| Incomplete build path | Indicate the severity of the problem reported when an entry on the classpath does not exist, is not legitimate or is not visible (e.g. a reference project is closed). | Error | 
| Circular dependencies | Indicate the severity of the problem reported when a project is involved in a cycle. | Error | 
| Incompatible required binaries | Indicate the severity of the problem reported when a project requires another project or library with an incompatible target JDK level (e.g. a project using 1.4 compiler compliance, but compiled against 1.5 system libraries on the build path). | Ignore | 
| Output location overlaps source location | Indicated the severity of the problem reported when a source entry's output location overlaps another source entry. | Error | 
| No strictly compatible JRE for execution environment available | Indicate the severity of the problem reported when project's build path contains an execution environment for which there is no strictly compatible JRE available in the workspace (e.g. a project using execution environment JavaSE-1.6 as JRE System Library, but the only Installed JREs available in the preferences are 1.7 and 1.8. | Ignore | 
| Compiler Compliance does not match used JRE | Indicate the severity of the problem reported when project's used JRE does not match the compiler compliance level selected. (e.g. a project using JRE 1.8 as JRE System Library, and the compiler compliance is set to 1.7). If the JRE being used is 9 or above and the --release option is selected and even if the complier compliance does not match the JRE being used, this option will be ignored. | Warning | 
| Duplicated resources | Indicate the severity of the problem reported when more than one occurrence of a resource is to be copied into the output location. | Warning | 
| Scrub output folders when cleaning projects | Indicate whether the Java Builder is allowed to clean the output folders when performing full build operations. | On | 
| Rebuild class files modified by others | Indicate whether class files which have been modified by others should be rebuilt to undo the modification. | Off | 
| Filtered resources | A comma separated list of file patterns which are not copied to the output folder. | Empty |