### Question:
PeerPolicy { public void setDiskUsageLimit( int diskUsageLimit ) { if ( diskUsageLimit < 0 || diskUsageLimit > 100 ) { throw new IllegalArgumentException( "Invalid disk usage limit." ); } this.diskUsageLimit = diskUsageLimit; } PeerPolicy( @JsonProperty( "peerId" ) final String peerId,
                       @JsonProperty( "diskUsageLimit" ) final int diskUsageLimit,
                       @JsonProperty( "cpuUsageLimit" ) final int cpuUsageLimit,
                       @JsonProperty( "memoryUsageLimit" ) final int memoryUsageLimit,
                       @JsonProperty( "networkUsageLimit" ) final int networkUsageLimit,
                       @JsonProperty( "environmentLimit" ) final int environmentLimit,
                       @JsonProperty( "containerLimit" ) final int containerLimit ); int getDiskUsageLimit(); int getCpuUsageLimit(); int getContainerLimit(); int getMemoryUsageLimit(); int getNetworkUsageLimit(); int getEnvironmentLimit(); void setContainerLimit( int containerLimit ); void setCpuUsageLimit( int cpuUsageLimit ); void setDiskUsageLimit( int diskUsageLimit ); void setMemoryUsageLimit( int memoryUsageLimit ); void setNetworkUsageLimit( int networkUsageLimit ); void setEnvironmentLimit( int environmentLimit ); String getPeerId(); @Override boolean equals( Object obj ); @Override int hashCode();  }### Answer:
@Test( expected = IllegalArgumentException.class ) public void testInvalidDiskUsage() { peerPolicy.setDiskUsageLimit( -1 ); }