TheDoctor TheDoctor - 5 months ago 15
Java Question

Use to initialize an object

I use

in my spring boot application to initialize some properties.
I know how i can initialize primitive datatypes but i don't know how to initialize objects.

That's my

@ConfigurationProperties(prefix = "bitmovin.bitmovin")
public class BitmovinConfig {

private S3InputConfig S3InputConfig = new S3InputConfig();
private int threadPoolSize;
private ArrayList<String> testFiles;

public BitmovinConfig() {

public S3InputConfig getS3InputConfig() {
return S3InputConfig;

public void setS3InputConfig(S3InputConfig s3InputConfig) {
S3InputConfig = s3InputConfig;

public int getThreadPoolSize() {
return threadPoolSize;

public void setThreadPoolSize(int threadPoolSize) {
this.threadPoolSize = threadPoolSize;

public ArrayList<String> getTestFiles() {
return testFiles;

public void setTestFiles(ArrayList<String> testFiles) {
this.testFiles = testFiles;

And that's my

bitmovin.bitmovin.threadPoolSize = 30
bitmovin.bitmovin.S3InputConfig = ??
bitmovin.bitmovin.testFiles= ??

How can i initialize an object or a list in


The Object, which i didn't create myself, i want to initialize:

public class S3OutputConfig {
public String name;
public S3Region region;
public String accessKey;
public String secretKey;
public String bucket;
public String prefix;
public boolean makePublic;


For the list, you have a couple of ways:


will set 3 items in testFiles. You can also control things via an index. The code above can be rewritten as


For the object, if you don't create it yourself in the code, you need to make sure it has a public default constructor. Then you navigate your object like any other object, using . to navigate. Assume your S3InputConfig has a name property (with getName and setName): name

You've seen use of lower-case hyphen a lot in Boot's documentation. We support the original format as well as hyphen lower case and others (see relaxed binding). The canonical representation for your config would be as follows:

bitmovin.bitmovin.test-files[2]=biz name