The document discusses robust programming practices, emphasizing the importance of fail-fast approaches and improved error handling. It provides code snippets illustrating better practices such as throwing exceptions when encountering null values or errors, rather than silently swallowing them. The overall focus is on creating more reliable and maintainable code.

1. /10@yegor256 1
Need It Robust?
Make It Fragile!
Yegor Bugayenko

2. /10@yegor256 2
less bugs

3. /10@yegor256 3
Fail Safe
vs.
Fail Fast

4. /10@yegor256 4
Fix
Report
Use
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int len(File f) {
if (f == null) {
return -1;
}
}
int len(File f) {
if (f == null) {
throw new Exception(
“file can’t be NULL”
);
}
}

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try {
stream.read();
} catch (IOException ex) {
ex.printStackTrace();
}
try {
stream.read();
} catch (IOException ex) {
throw new RuntimeException(
“failed to read stream”,
ex
);
}
exception swallowing

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void push(int x) {
if (pos < array.length) {
array[pos++] = x;
}
}
void push(int x) {
if (pos >= array.length) {
throw new Exception(
“array is full”
);
}
array[pos++] = x;
}

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@Override
void save() {
// not implemented yet
}
@Override
void save() {
throw new Exception(
“not implemented yet”
);
}

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file.delete();
if (!file.delete()) {
throw new Exception(
“failed to delete file”
);
}

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User find(int id) {
if (/* not found */) {
return null;
}
// continue...
}
User find(int id) {
if (/* not found */) {
throw new Exception(
“user not found”
);
}
// continue...
}

11. /10@yegor256 11
Fix
Report
Use
Deploy

12. /10@yegor256 12
www.yegor256.com